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. 2024 Jan 30;9(6):6219–6234. doi: 10.1021/acsomega.3c08353

Lipid Nanoparticle-Based Delivery System—A Competing Place for mRNA Vaccines

Xinyu Zhang †,‡,∥, Yuanfang Li §,*, Zehua Zhou †,*
PMCID: PMC10870384  PMID: 38371811

Abstract

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mRNA, as one of the foci of biomedical research in the past decade, has become a candidate vaccine solution for various infectious diseases and tumors and for regenerative medicine and immunotherapy due to its high efficiency, safety, and effectiveness. A stable and effective delivery system is needed to protect mRNAs from nuclease degradation while also enhancing immunogenicity. The success of mRNA lipid nanoparticles in treating COVID-19, to a certain extent, marks a milestone for mRNA vaccines and also promotes further research on mRNA delivery systems. Here, we explore mRNA vaccine delivery systems, especially lipid nanoparticles (LNPs), considering the current research status, prospects, and challenges of lipid nanoparticles, and explore other mRNA delivery systems.

1. Introduction

When mRNA is used for vaccines, it can encode target antigens, which are usually produced by DNA transcription in vitro1 and subsequently inoculated into the body. mRNA is translated into an antigenic protein in the body, triggering an adaptive immune response.2 The whole process does not involve cell culture, so it is simple, fast and attractive and is a candidate form of vaccine suitable for responding to outbreaks of new infectious diseases, such as COVID-19.3 Researchers’ efforts in mRNA purification, sequence optimization and nucleoside chemistry have endowed mRNAs with stability and strong immunogenicity.4−7 Research based on mRNA itself has paved the way for its application. Although the optimization and modification of mRNAs are key to their successful translation into antigenic proteins, we must admit that the delivery system makes the same important contribution to the performance of mRNA vaccines. Naked mRNA is easily degraded in systemic circulation, whether it is modified, and the degradation products are small enough to be excreted by the kidney. These degraded small molecules are not ingested or displayed by antigen-presenting cells, nor will they trigger an adaptive immune response through the immune organs. In the past decade, a large number of new nucleic acid nanoparticle delivery systems have emerged8−11 that aim to encapsulate mRNAs effectively to protect them from degradation by serum nucleases and promote endocytosis and endosome escape to successfully trigger the immune response. Among them, LNPs have become a highly concerning delivery system because of their efficient delivery characteristics.

In the 1960s, the first generation of LNPs, which were called liposomes, appeared.12 They are produced in water and have a closed phospholipid bilayer.13 Lipids can enhance the water solubility of drugs; therefore, they are considered to have potential as drug delivery systems.12 In recent years, nanotechnology has been developed, and the function of nanoliposomes has further developed to realize simple targeting or other simple functions.14 LNPs developed for mRNA delivery in recent years consist of ionizable cationic lipids, phospholipids, cholesterol, polyethylene glycol (PEG) lipids, and mRNAs (Figure 1). LNPs have been studied as drug delivery systems that encapsulate small molecules, nucleic acids, small interfering RNAs (siRNAs) and mRNAs.15−20 Ionizable cationic lipids contain ionizable amine groups, self-assembled hydrophobic tails, and connectors. After entering the body, the peptide is ionized in an acidic environment, which helps to form a hexagonal phase, facilitating the escape of mRNA from degradation in the body and release into the cytoplasm.21−24 The choice of PEG lipid depends on the molar mass and length of the PEG, which can affect the overall outcome, including targeted delivery and cell uptake efficiency.25,26 Auxiliary lipids and cholesterol also contribute to the formation of LNPs, which contributes to the fluidity (or rigidity) of LNPs.27 In addition, the presence of the cold-terol complex affects the delivery and distribution of LNPs, and specific modifications enhance the targeting of certain cell types.28,29

Figure 1.

Figure 1

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Composition of the mRNA-LNPs. mRNA: core active ingredient; ionizable cationic lipids: electrostatically adsorbed nucleic acids and encapsulated nucleic acids; phospholipids: accelerated structural transformation of LNPs in cells; cholesterol: stabilized structure of LNPs such that LNPs can enter cells via low-density lipoprotein (LDL); PEG: improved LNP stability, prolonged circulation time in vivo, and, to a certain extent, reduced liver enrichment.

The success of mRNA in treating COVID-19 has laid the foundation for its application in other places and established the confidence of researchers. The authors believe that the next successful use of mRNA vaccines is to be expected because LNPs are widely used in nucleic acid delivery research and clinical applications, and nearly 80 kinds of nucleic acid drugs based on LNPs have entered the clinical stage.30 Although some clinical data are still available after approval and emergency use authorization (EUA) are obtained from the U.S. Food and Drug Administration (FDA), LNPs still have many problems that cannot be bypassed. There are several obstacles inside and outside the cells that prevent the application of mRNA LNPs within a wide range. Liver enrichment is a common phenomenon in the mouths of LNP patients. LNPs require some effort to pass through the liver system, and nanoparticles must first be isolated from Kupffer cells (which are macrophages resident in the liver). Kupffer cells in the liver can absorb LNPs of different sizes. In addition, LNPs also interact with hepatic sinusoidal endothelial cells (LSECs) to prevent LNPs from passing through the liver system (Figure 2).31 A total of 30–90% of these drugs are concentrated in the liver, which leads to drug deviation during nonliver-targeted administration,32 thus affecting the therapeutic efficacy. In addition, even for LNPs approved by the FDA for sale, only 1–4% of nucleic acids have the opportunity to escape from endosomes and reach the cytoplasm,33 which is the main barrier for LNPs to play their role after entering cells. These limitations are the main obstacles to organ and cell targeting of mRNA vaccines. Although mRNA vaccines can induce an immune response by targeting antigen proteins, more in-depth research and additional attention need to be given to the stability and toxicity of these agents. This review discusses the research status of mRNA vaccine delivery systems.

Figure 2.

Figure 2

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mRNA-LNPs are taken up by Kupffer cells with LSECs as they pass through the hepatic tract, leading to unwanted hepatic enrichment.

2. mRNA Vaccines

2.1. Mechanisms of Action of mRNA Vaccines

When the concept of mRNA vaccines was introduced, researchers first attempted to use in vitro transcribed (IVT) mRNA as a protective vaccine.34,35 However, bare IVT mRNA is not sufficient to drive full protective immunity in most cases,36 and although complexation of mRNA with fish sperm proteins effectively enhances the immunostimulatory potential of nucleic acids, it is still associated with the risk of reducing its translatability, thus reducing the preventive effect of the vaccine.37 Another challenge for mRNA vaccines is the inability to exercise the correct function in dendritic cells (DCs), which may require special means to direct DC activation.37 In addition, the poor in vivo stability of mRNAs, their susceptibility to degradation by nucleases, and their high molecular weight (MW) and high negative charge, which prevent them from entering cells by passive diffusion, are also issues that need to be addressed. LNPs, commonly used nonviral vectors for delivering mRNA vaccines, show great potential for protecting mRNAs from nuclease degradation and facilitating antigen-presenting cell (APC) uptake as well as for carrying their own adjuvant effect to enhance the immunogenicity of endogenous proteins encoded by mRNAs.

The mRNA vaccine relies on the interaction of LNPs with the cell membrane to molecularly deliver the mRNA encoding the target antigen to the cytoplasm of inoculated individual cells, where the mRNA can be translated into endogenous immunogenic proteins to elicit an immune response (Figure 3A). When a pathogen invades, the host can then rely on its immune memory to respond rapidly to clear the antigen. mRNA-LNPs enter the cell through endocytosis, where they can form endosomes that enter the cytoplasm. The acidic environment inside the endosome causes the headgroup of ionizable cationic lipids, one of the components of LNPs, to protonate and carry a positive charge, which attracts and binds the anionic headgroup of phospholipids in the endosomome. Upon binding, the hydrophobic tails of cationic lipids and phospholipids expand, and the endosomal membrane is disrupted, thereby allowing the mRNA cytoplasm to undergo translation and preventing lysosomal degradation of the endosome.38,39 Activation of mRNA for humoral immunity is similar to that of most conventional vaccines, and although the exact process of activation of CD8+ T cells is currently not fully understood, endogenous antigens are considered potent conditions and antigenic peptides need to be presented to CD8+ T cells via the major histocompatibility complex class I (MHC I) molecular pathway, which mRNA vaccines can do very well, exerting both humoral and cellular immunity at the same time (Figure 3B).

Figure 3.

Figure 3

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Process by which mRNA-LNPs are taken up and the mechanism by which adaptive immunity is induced. (A) mRNA-LNPs enter the cytoplasm via the cytosol, release mRNAs and are translated into proteins that act as immunogens. (B) Endogenous proteins are degraded by the proteasome to become peptides and are presented by MHC I to CD8+ T cells for activation, while proteins expressed on membranes or secreted can also be recognized by antigen-specific B cells as signals for B-cell activation. (C) Proteins translated from mRNAs can also activate CD4+ T cells.

2.2. mRNA-LNPs against Viruses

mRNA vaccines have emerged as promising alternative platforms to traditional vaccines. They are easy to produce, low cost, safe, and highly effective, making them ideal candidates for the prevention and treatment of infectious diseases. The development of an mRNA vaccine against COVID-19 was the first successful introduction of the entire mRNA platform. Pfizer/Biontech and Moderna are two COVID-19 mRNA vaccines (BNT162b2 and mRNA-1273) that were approved and showed 94.1%40 and 95%41 efficacy, respectively. The success of mRNAs in fighting COVID-19 has given confidence. Researchers have studied the effectiveness of mRNA vaccines against other viruses to improve the use of these new technologies for protecting human health.

mRNA-LNP was also applied to the Zika virus and influenza virus (H7N9 and H10N8). Mice and nonhuman primates produced high neutralizing antibody titers (1/100,000)42 against Zika virus after administration of two or more single doses of the vaccine; in mice and ferrets, a single dose of the vaccine produced HA-inhibitory and potent neutralizing antibodies against H7N9 and H10N8.43 LNP-embedded modified mRNA vaccines encoding viral glycoproteins have been investigated in preclinical studies against a variety of viruses, including Ebola,44 HIV-1,45 and Nipah virus.46 These studies demonstrated that the vaccines were able to induce high glycoprotein-specific neutralizing antibody titers as well as antibody-dependent cytotoxicity, thereby protecting animals from lethal viral attacks. The mRNA-LNPs also showed superior immune strength to other vaccine forms when glycoproteins from cytomegalovirus (CMV),47 vzv,48 RSV,49 and the rabies virus50 were used as immunogens.

2.3. mRNA-LNPs for Cancer Immunotherapy

mRNA vaccines have emerged as promising platforms for the development of cancer vaccines. mRNA vaccines work by introducing single-stranded molecules that encode tumor neoantigens. mRNA-based cancer vaccines encode key components of the immune response process, such as tumor-specific antigen (TSA), tumor-associated antigen (TAA), and immunomodulatory factors, which promote immune activation to carry out antitumor functions.51,52 Upon injection, the mRNA cancer vaccine is delivered to the cytoplasm of the APC, where it is subsequently translated into neoantigenic proteins and stimulates TLR7 and TLR8.53,54 Subsequently, mature APCs are translocated to the lymph nodes, where they generate significant humoral and cellular immunity.55,56 Compared with conventional vaccines, mRNA vaccines induce a more potent type I interferon response and efficiently trigger human CD8+ T-cell responses,54 which play a key role in tumor eradication. In a previous study, Oberli et al. designed and optimized an LNP library for the delivery of an mRNA vaccine encoding the model antigen ovalbumin (OVA). The vaccine successfully induced potent CD8+ T-cell activation and immune responses. CD8+ T-cell activation was successfully induced, and the overall survival of B16F10 melanoma patients was prolonged. prolonged overall survival in a B16F10 melanoma model.57 In another study, Bevers et al. optimized an mRNA-LNP formulation by adjusting the molar concentration of the four components of the mRNA-LNP formulation to optimize the delivery of the mRNA-LNP vaccine encoding HPV16.58 The optimal mRNA-LNP vaccine induced a strong CD8+ T-cell response and enhanced uptake of the mRNA into the cells. These results demonstrated the feasibility of using mRNA-LNPs as a cancer vaccine.58

A TSA-based vaccine, mRNA-4157, which is capable of encoding up to 34 antigens, is currently being evaluated for its efficacy in the treatment of melanoma (NCT03897881). The results of the phase IIb KEYNOTE-942 trial suggest that mRNA-4157/V940 in combination with pembrolizumab may be a potential adjuvant therapy for melanoma because patients receiving this combination have a significantly lower risk of disease recurrence than patients receiving only the PD-1 inhibitor alone. Patients treated with this combination have a significantly lower risk of disease recurrence.59 The ability of the autologous gene cevumeran (BNT 122), which contains up to 20 neoantigens, to stimulate immunity to neoantigens in patients with resected pancreatic ductal adenocarcinoma (PDAC) was tested in a phase 1 clinical trial. The BioNT111 vaccine developed by BioNTech is an mRNA cancer vaccine that encodes four TAAs, namely, New York Esophageal Squamous Cell Carcinoma 1 (NY-ESO-1), Melanoma-Associated Antigen A3 (MAGE-A3), tyrosinase, and tensor protein homologous transmembrane phosphatase (TPTE).60 These mRNAs were encapsulated in liposomes and administered intravenously to patients. In a phase I trial, a vaccine alone or in combination with immune checkpoint inhibitors (ICIs) induced durable responses and had a favorable safety profile in patients with advanced melanoma.60 These findings suggest that the BNT111 vaccine has potential as a candidate for melanoma treatment. The success of mRNA cancer vaccines in combination with immune checkpoint inhibitors has inspired further ideas on the use of mRNAs encoding immunostimulants that enhance the efficacy of immune checkpoint inhibitors. Trials of cytokine-encoded mRNA products by BioNTech and Moderna have yielded satisfactory results.61,62 For example, Moderna-generated intratumorally administered mRNA-2416, which encodes OX40L, demonstrated safety and tolerability in a phase I trial and triggered broad proinflammatory activity and an altered TME.62 In addition, BioNTech’s BNT131 (SAR441000) (NCT03871348), which encodes IL-12sc, IL-15 sushi, and IFN-α for intratumoral administration, is being tested as a monotherapy as well as in combination with cemiplimab in patients with advanced solid tumors to alter the TME.

3. Composition of LNPs

When the in vivo delivery of mRNA was first investigated, viruses as natural nucleic acid delivery systems first attracted the attention of researchers. However, most viruses are still dangerous because of their self-integrating DNA and pathogenicity. Risk-reducing viral vectors still do not fully address these shortcomings and are difficult to produce.63 Nonviral vectors, which are negatively charged themselves, interact with negatively charged mRNAs, bind mRNAs and enter the cell via endocytosis. This approach circumvents the drawbacks of viral vectors but results in a decreased transfection efficiency. In the 1990s, researchers experimented with the use of cationic liposomes64 and fish sperm proteins,65 among others, as delivery systems, followed by further attempts with biodegradable, ionizable polymers.66 However, the complex structure and high toxicity of these materials as well as their lower transfection efficiency prevent them from entering the clinic. LNPs solve these problems to some extent with good biocompatibility and high transfection efficiency, as well as greatly reduced toxicity. As a result, LNPs have become the most widely used mRNA delivery system67 and have advantages over other delivery systems.

3.1. Ionizable Cationic Lipids

Ionizable cationic lipids are pH sensitive, and their head groups can transfer charge, changing from a positively charged state at low pH to a neutral state at physiological pH.68,69 This allows the formation of mRNA–LNP complexes, and LNPs provide a safe and stable environment for mRNA in a pH-dependent manner.70,71 Ionizable cationic lipids can remain neutral in the blood, so the pH of the mRNA released by LNPs can be adjusted to reduce toxicity.72 In addition, in the low-pH environment of the inner body, ionizable cationic lipids can obtain a positive charge, which makes the inner body envelope unstable and allows the nanoparticles to escape from the inner body compartment.73

3.2. Polyethylene Glycol

Another key component of lipid nanoparticles is PEG, which has a significant effect on their properties. The most commonly used PEG in LNP structures is PEG2000 (PEG, MW = 2000), which was shown by Oberli et al. to contribute to smaller LNP particle sizes as well as stronger T-cell responses.74 Rondine et al. explored the effect of the structure–activity relationship of PEG-peptide complexes on the uptake of Kupffer cells and showed that the smaller the MW of PEG was, the more pronounced the hepatic escape effect of the nanoparticles was when the peptide’s structure was fixed.75 PEG can increase the ability of mRNA LNPs to escape conditioning and phagocytosis by macrophages. When PEG2000 was used, modulation of the PEG density and chain length allowed it to interfere with the binding of modulator molecules (e.g., C3b and iC3b) to their corresponding receptors expressed on macrophages by means of spatial site barriers, enhancing the mobility of the PEG chains, and softness and stretching have been shown to have similar significant effects.76 PEG on the surface of LNPs can stabilize the spatial structure of LNPs and prevent nonspecific binding with some proteins.77 Due to its hydrophilicity, the addition of PEG chains results in a hydration cloud with a large excluded volume of LNPs, which reduces the interaction of LNPs with neighboring LNPs or blood constituents. The flexibility of the PEG conformation, which has a large degree of freedom, renders the thermodynamic interpenetration of the PEG corona unfavorable for other substances.78 Therefore, the addition of PEG can lead to a significant prolongation of the in vivo circulation time of LNPs. The PEG content in LNPs is usually positively correlated with the blood circulation time.79

3.3. Other Lipids

Cholesterol, phospholipids, and PEG are the components of LNPs, except for ionizable cationic lipids. Cholesterol is key to the stability of LNPs, and its role in cell transfection experiments has been proven.80 When the transition temperature is low, the cholesterol content in the LNPs must increase, which can cause the LNPs to transition from the lamellar phase to the hexagonal phase.81 These processes are necessary for LNPs to release mRNA and interact with the endosomal membrane.82 The role of phospholipids in LNPs is to stabilize the structure, which is related to the formation and destruction of the phospholipid bilayer to promote endosome escape. In addition, some phospholipids exhibit polymorphism, which can cause the inner body membrane to change from a layered to a hexagonal phase.83,84 Moreover, the negatively charged phosphoric acid group may participate in cationic charge neutralization, which also contributes to phase transition and internal body escape.85,86

3.4. Clinical Application of LNPs

Malone et al. reported that the cationic lipid n-[1-(2,3-dioleoyloxy)propyl]-N,N,n-trimethylammonium chloride (DOTMA) can be used as an mRNA transfection reagent to transport mRNAs into cells.87 However, it can cause proinflammatory and proapoptotic toxicity in vivo, so it can be quickly removed during recycling.88 Therefore, since ionizable lipids can promote the escape of mRNAs into endosomes and are neutralized at physiological pH, they can be more stable, safer, and more suitable for mRNA vaccine delivery systems.89 Ampatro Dlin-MC3-DMA (Figure 4A)90 in the LNP formula is the first siRNA drug approved by the FDA worldwide. Moderna used Dlin-MC3-DMA to test an mRNA vaccine based on Zika virus and influenza virus and further conducted preclinical and clinical studies.42,43 Research has shown that the vaccine form of mRNA-LNPs can generate strong protective immune responses in mice, ferrets, and nonhuman primates, and preliminary data from the first human trial of mRNA-LNPs using influenza virus as the immunogen has shown some success.42,43 However, the alkyl tail of linoleic acid in Dlin-MC3-DMA is not easily degraded, which may lead to toxicity when the amount of this compound is too high.91 The novel Pfizer/Biontech and Moderna vaccines, two COVID-19 mRNA vaccines (BNT162b2 and mRNA-1273) have recently been approved by the FDA and symbolize the successful use of LNPs in the field of mRNA vaccines. These two LNPs were rapidly developed to prevent the spread of COVID-19. The lipids produced by Moderna are called SM-102 (also known as lipid H; Figure 4B). Its tail has more branches, which can increase its efficacy, and the ester bond introduced by this tail improves its biodegradability in vivo and safety.22,92 Almost at the same time, Biontech used ALC-0315 (Figure 4C), which has a chemical structure similar to that of SM-102, as the ionizable lipid in its COVID-19 mRNA vaccine LNP formula.91,93 Both mRNA vaccines have a protective effect of more than 90%.40,94 Monitoring of populations vaccinated with these two types of mRNA vaccines showed good protective efficacy, although the protection against mutations may be relatively poor.41 The molar ratio of LNPs developed by Moderna was SM-102: PEG: cholesterol: phospholipids (DSPC) = 50: 1.5: 38.5: 10. The molar ratio of the LNP formula developed by Pfizer/Biontech was ALC-0315: PEG: cholesterol: phospholipids (DSPC) = 46.3: 1.6: 42.7: 9.4.95 The particle size of the LNPs in these two formulations is approximately 80–100 nm,22 and the LNPs contain approximately 100 mRNA molecules;96 additionally, the LNPs perform well in the prevention and control of COVID-19.

Figure 4.

Figure 4

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Molecular formulas of Dlin-MC3-DMA (A), SM102 (B), and ALC-0315 (C).

In addition to the three approved LNPs mentioned above, a considerable number of LNP-based products are in clinical trials (Table 1). These studies demonstrated that LNPs are effective in vivo delivery vehicles, highlighting the need for a deeper understanding of LNP delivery systems.

Table 1. Current Clinical Trials That Are Ongoinga.

Trial Condition Intervention Sponsor Phase
NCT04283461 COVID-19 Immunization mRNA-1273 NIAID I
ModernaTX, Inc.
NCT04785144 COVID-19 Immunization mRNA-1273 NIAID I
mRNA-1273.351 ModernaTX, Inc.
NCT05057182 COVID-19 Immunization BNT162b2 The University of Hong Kong IV
NCT05658523 COVID-19 Bivalent Moderna MCRI, CEPI and PDIII III
Novavax
NCT04816669 COVID-19 BNT162b2 BioNTech SE Pfizer III
NCT05231369 COVID-19 ChulaCov19 BNA159 mRNA vaccine Chula CRC, ACRO I
NCT04847102 COVID-19 SARS-CoV-2 mRNA Vaccine Walvax Biotechnology, Abogen Biosciences, Yuxi Walvax Biotechnology III
NCT04776317 COVID-19 ChAdV68-S; ChAdV68-S-TCE NIAID I
SAM-LNP-S; SAM-LNP-S-TCE Gritstone bio, Inc.
NCT04821674 COVID-19 DS-5670a Daiichi Sankyo I/II
NCT04480957 SARS-CoV-2 ARCT-021 Arcturus Therapeutics, Inc. I/II
NCT04844268 SARS-CoV-2 VACCINE RNA MCTI SENAI CIMATEC I
CIMATEC HDT (HDT-301)
NCT04811664 SARS-CoV-2 Infection Moderna NIAID III
COVID-19 Vaccine
NCT05534048 SARS-CoV-2 Infection PTX-COVID19-B Everest Medicines (Singapore) Pte. Ltd. III
Comirnaty
NCT05534035 SARS-CoV-2 Infection PTX-COVID19-B Everest Medicines (Singapore) Pte. Ltd. III
Vaxzevria
NCT05057169 COVID-19 Vaccination BNT162b2 The University of Hong Kong IV
CoronaVac
NCT05639894 Respiratory Syncytial Virus Infection RSV mRNA LNP CL-0059 Sanofi I/II
RSV mRNA LNP CL-0137
LNP CL-0137 High Dose
NCT05516459 Coronavirus Infections Pfizer BNT162b2 Vaccine SUMC Negev  
NCT05755620 Influenza Influenza Virus Quadrivalent NIAID I
Inactivated Vaccine
VRC- FLUNPF099–00-VP
NCT04758962 Virus Diseases 1 μg CoV-2 SAM (LNP) GlaxoSmithKline I
NCT03897881 Melanoma mRNA-4157 ModernaTX, Inc. II
Pembrolizumab
NCT03323398 Refractory Solid Tumor mRNA-2416 ModernaTX, Inc. I/II
Malignancies or Lymphoma Durvalumab
Ovarian Cancer
NCT02314052 Hepatocellular Carcinoma DCR-MYC Dicerna Pharmaceuticals, Inc. I/II
NCT01437007 Hepatic Metastases involving TKM-080301 National Cancer Institute (NCI) I
Pancreas Cancer, Gastric Cancer, Breast Cancer, Ovarian Cancer, Colorectal Cancer National Institutes of Health Clinical Center (CC)
NCT02110563 Solid Tumors, Multiple Myeloma, Non-Hodgkin Lymphoma, Pancreatic Neuroendocrine Tumors, PNET,NHL DCR-MYC Dicerna Pharmaceuticals, Inc. I
NCT04675996 Solid Tumor INT-1B3 InteRNA I
NCT05703971 Small Cell Lung Cancer OTX-2002 Genprex Inc. I/II
Extensive Stage quaratusugene
ozeplasmid
atezolizumab
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a

From clinicaltrials.gov. Abbreviations: NIAID = National Institute of Allergy and Infectious Diseases; MCRI = Murdoch Childrens Research Institute; CEPI = Coalition for Epidemic Preparedness Innovations; PDIII = The Peter Doherty Institute for Infection and Immunity; ChulaVRC = Chulalongkorn University Chula Vaccine Research Center, Bangkok, Thailan; ACRO = Academic Clinical Research Office, Faculty of Medicine, Khon Kaen University BioNet-Asia; SUMCs = Soroka University Medical Center Ben-Gurion University of the Negev.

4. Challenges in LNP design

As the most widespread and prominent mRNA vaccine delivery vector, LNPs not only demonstrate potential but also present problems that need to be solved. The resolution of these problems will expand the application of mRNA vaccines to a greater extent.

4.1. LNP Targeting

When LNPs are injected intravenously (IV) or intramuscularly (IM), a majority of the LNPs accumulate in the liver, which contradicts the original intention of achieving the function of mRNA vaccines. Researchers are attempting to modify LNPs to alter organ targeting preferences. The charge, composition, and size of LNPs can affect their trafficking, absorption, and organ distribution.97−99 Research on LNP targeting has become a global research hotspot. The progress made in these studies has helped us gain a deeper understanding of the adaptability of LNPs to immune organs.100−102

4.1.1. Modifications Made to Achieve Immune Organ Targeting

Recent studies have shown that changing the apparent acid dissociation constant (pKa) of LNPs can enable LNPs to target extrahepatic tissues (such as the spleen or lungs).103 The pKa of LNPs enriched in the liver is generally between 6 and 7; when the pKa is between 2 and 6, LNPs exhibit good spleen enrichment ability.104 The surface pKa ≈ 5.7 of spleen-targeted OF-Deg-Lin FLuc mRNA LNPs also provides a good example.105 The above phenomenon may be due to the different head groups of different ionizable cationic lipids determining the pKa, which determines the surface charge difference of LNPs, affects their ability to interact with different types of serum proteins, and ultimately leads to their different distributions in the body. The negative surface charge of LNPs is related to their uptake in the spleen.106 Cheng et al. recently found that the presence of a fifth component, called “selective organ targeting (SORT)”, can alter the organ targeting effect of LNPs in vivo.107 Studies have shown that SORT lipids can affect the apparent pKa values of LNPs and the interaction between LNPs and serum proteins. Changing the quantity and type of SORT lipids can endow LNPs with different targeting selectivities. Interestingly, when the lipid 18PA, which has a negative surface charge, is added to LNPs, spleen targeting can be achieved. Next, 18PA was replaced with 14PA and 18BMP, which also had negative surface charges. The results showed that the ability of the LNPs to target cells was independent of the structure of the fifth component. These findings are undoubtedly exciting and can be foreseen for the further development of mRNA vaccines. Currently, the LNP-SORT platform has been established.108

The spleen is an immune organ that contains a large number of lymphocytes. A library of ionizable amino polyesters (APEs) was synthesized by the ring-opening polymerization of lactones and tertiary amino alcohols. Fusion of APE to LNP (i.e., APE-LNP) resulted in the observation of an increased preference of LNP for splenic antigen-presenting cells.109 In another study, Anderson et al. synthesized a series of alkenyl amino alcohol (AAA) lipids, named OF-XX, via a ring-opening reaction between an alkenyl epoxide and a polyamine core. One of them, OF-02 LNPs, showed notable hepatic targeting.110 To achieve splenic targeting, they later designed OF-Deg-Lin lipids based on the lipids OF-02, which have a diketopiperazine core and four esterified unsaturated tails. A specific preference for B lymphocytes in the spleen was achieved.111 In addition, by increasing the length of the carbon chain to 4, the lipid named OF-C4-Deg-Lin was further modified, and this lipid possessed even better mRNA delivery capacity.112 Gomi et al. prepared a series of LNPs using alcohol-soluble phosphatidylserine (PS) molecules to achieve splenic targeting, which is a potential direction for the development of vac-cine LNPs.113 Dong et al. designed TNT-b10, optimized on the basis of the siRNA carrier TNT-a 10, which has altered functional group positions and a significantly improved ability to target the spleen.114 Ni et al. also studied several ionizable lipids (Pi lipids) with piperazine, where Pi-A10 can preferentially deliver mRNA to immune cells in the liver and spleen, with 50% expressed in macrophages of the spleen and 30% expressed in DCs of the spleen.115 Targeted delivery of DCs is also necessary for cancer vaccines to function. Veiga et al. designed an unmodified RNA lipid complex (RNA-LPX) that targets spleen DCs to activate immune responses by reducing the content of ionizable cationic lipids. Significant T-cell responses were observed in clinical trials, proving that this method can work.116 Furthermore, Tomácz et al. combined CD4 antibodies with LNPs and compared with unmodified LNPs with CD4, the accumulation rate of radiolabeled mRNA in the spleen was greater during systemic administration. Cre-based reporter gene expression experiments also showed stronger spleen- and lymph node-targeting ability.117 Epstein et al. coupled CD5 antibodies to the surface of LNPs and found a trend toward targeting lymph node T cells after systemic administration, enabling T cells to be reprogrammed in vivo.118 DC205 is highly expressed in some DCs, and Katakowski et al. reported that modifying LNPs with a single-chain antibody specific to DEC205 can lead to DC205+ DC uptake in the spleen.119 These studies demonstrated that LNPs can target specific immune cells by coupling certain antibodies or ligands, achieving immune organ targeting, and stimulating immune response activation in specific viral infection backgrounds.

In addition to the above research, Okuda et al. reported that the particle size is also one of the factors affecting the targeting preference of LNPs. They found that adding salt to mRNA buffer can increase the particle size to approximately 200 nm, allowing the particles to travel more to mouse spleen lymphocytes and DCs without changing the LNP composition or effectively activating immune cells.100

4.1.2. Administration Routes

In addition to modifying the LNP itself, local administration, such as via lymph node intramuscular injection, can also increase the targeting potential of LNPs, which prevents them from reaching specific organs after systemic administration and helps in the selective delivery of LNPs.

In preclinical or clinical trials, LNPs are mainly administered through intradermal, subcutaneous, or intramuscular injection, allowing them to target nearby draining lymph nodes and present antigens to T cells, exposing antigens to B cells and activating the immune response.120−122 The two COVID-19 mRNA vaccines currently on the market are administered through intramuscular injection. In regard to tumor vaccines, in addition to the above three pathways, colon administration, nasal drip administration, or intratumoral administration can also improve the targeting and efficacy of LNPs.123−125 The method of needle-free injection can alleviate patient pain while also allowing LNPs to reach immune cells under the skin under the influence of high-pressure sources.

4.2. Endosome Escape

When LNPs enter the target cell, the mRNA inside must escape from the endomes to the cytoplasm to be translated into the target protein for function. However, most mRNAs are transported by the endosome to the lysosome for degradation,126,127 and only a small portion of the proteins can escape into the cytoplasm.128,129 This situation has been the main barrier for accounting for drug delivery for more than 50 years130 and is another major problem that needs to be solved in the application of LNPs. A better understanding of the interactions between LNPs and in vivo pathways can guide the design of better treatment methods. It is necessary to improve the effectiveness of mRNA vaccines and allow more mRNAs to escape from endosomes. Currently, it is possible to advance this field by changing the LNP structure to address the mechanism of endosome escape, but there is no perfect method for achieving endosome escape. To ultimately achieve the goal of internal escape, any feasible opportunity is worth trying.

4.2.1. Mechanism of Endosomal Escape

In a series of processes from early endosomes to late endosomes and then to lysosomal degradation, the pH steadily decreases from physiological 7.4, early endosomes decrease to 6.5, late endosomes decrease to 6, and lysosomal degradation decreases to 5.131 Then, LNPs can escape endophagy through a membrane phase transition related to pH. The highest proportion of ionizable cationic lipids in the LNP structure determines the basic properties of LNPs, which are undoubtedly closely related to the function of endosome escape.132 When the hydrophobic tail of ionizable cationic lipids is equivalent in size to the head, LNPs are dispersed in a bilayer form in water.133 Early endosomes are vesicles that engulf LNPs. As endosomes mature, the pH gradually decreases and the head of the ionizable cationic lipids gradually acquires a positive charge, allowing them to interact with negatively charged endosomes. During this process, endosomes completely fuse with LNPs, allowing mRNA to be released into the cytoplasm (Figure 5).

Figure 5.

Figure 5

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Ionizable cationic lipids carry a positive charge in an acidic environment and fuse with endosomal membranes to release mRNA, with the remainder being degraded by lysosomes.

4.2.2. Modification of Ionizable Cationic Lipids

Because ionizable cationic lipids fuse with endosomal membranes under acidic conditions and because the hydrophobic tail expands, it is more advantageous for them to insert into the phospholipid bilayer to form the HII phase if they have a conical structure. The size of the hydrophobic tail of ionizable cationic lipids strongly influences the efficiency of endosomal membrane inversion. When the hydrophobic tail has an unsaturated bond, the spatial hindrance created by the rigid structure of the cis-double bond facilitates the formation of the HII phase and promotes the escape of endosomes.134 Yusuke Sato et al. developed a library of ionizable cationic lipids that can respond to pH changes in 2019.135 Among them, the lipid CL1H6, which has a high endosomal escape efficiency, consists of a hydrophilic head with a tertiary amine and two tails with double bonds. The hydrophilic head of CL1H6 affects the apparent pKa of the LNP to control endosomal escape and organ preference, a process that is achieved by membrane fusion rather than disruption of the endosomal membrane (analyses showed an intracellular translocation ED50 of 0.0025 mg/kg). Tanaka et al.136 developed a self-degrading lipid molecule (ssPalmO Phe) based on a double-bonded hydrophobic tail that can accelerate the breakdown of LNPs and promote the release of RNA into the cytoplasm, in which the inserted aromatic ring can alter the structure of LNPs to enhance endosomal escape.136 The above evidence suggests that hydrophobic tails carrying unsaturated bonds can indeed increase endosomal escape, and it is speculated that the rate of endosomal escape increases with an increasing number of unsaturated bonds. Based on these results, Heyes et al. speculated that short-branched trialkyl hydrophobic structural domains may also improve the endosomal escape efficiency of LNPs.137

4.2.3. Modification of Other Lipids

As mentioned earlier, LNPs are composed of four components, each of which plays its own role, and the formation of LNPs is indispensable. In addition to increasing the escape rate of endosomes by altering ionizable cationic lipids, optimization based on cholesterol and phospholipids can also contribute to this process. Cholesterol is related to the structural stability of LNPs and can regulate membrane fluidity138 while directly disrupting the stability of endosomes and promoting mRNA release to the cytoplasm.139 Researchers have shown that the length of the alkyl tail, the flexibility of the sterol ring, and the polarity of −OH are related to improvement of transfection efficiency in cholesterol research. Siddharth et al. prepared a series of cholesterol analogs to replace LNPs and found that when cholesterol analogs with alkyl substituents at the C-24 position were used in the LNP structure, the LNPs showed increased transfection efficiency.140 The mRNA release of LNPs formed by replacing cholesterol with sitosterol increased by more than 10-fold during transfection.140 Gaurav et al. also discovered that the use of β, the assembly of LNPs with sitosterol instead of cholesterol, can enhance the transfection ability of LNPs. It is speculated that β-sitosterol provides a polyhedral shape to LNPs, thereby promoting endosome escape.141 Increasing the proportion of phospholipids in LNPs can improve the delivery of mRNAs. The formation of LNPs requires phospholipids to regulate the electrostatic interaction among ionizable cationic lipids, mRNAs, and solvents. The LNP membrane is rich in phospholipids, while the inner membrane is rich in a phospholipid bilayer. This membrane is rich in bis(monoacyl-glycerol)phosphate (BMP). Unlike phospholipids containing PC and PS groups (which can increase the stability of the LNP bilayer structure), phospholipids containing PE can guide the bending of the LNP membrane to promote fusion with the inner membrane. Daniel et al. attempted to explain the role of phospholipids in endosome escape based on the influence of chain length and the unsaturation of phospholipids when the PE and PC head groups remain unchanged.142 The results showed that LNPs with PE as the head base had the highest efficiency in delivering mRNA. Currently, an increasing number of LNPs are using sterol lipids to replace cholesterol to increase internal body escape, and on this basis, sterol lipids with PE heads can further improve the internal body escape efficiency of LNPs.

4.2.4. Adding Exogenous Substances to Promote Endosome Escape

In addition to the modification of the LNPs themselves, the addition of other components is another method for improving endosome escape. Like for most proteins, Yusuke et al.’s research showed that protamine itself carries a large amount of negative charge, and when mixed with LNPs, it can effectively control the positive charge toxicity of LNPs.143 YSK05 is a cationic lipid designed specifically for endosomal escape. The amount of fluorescent protein expressed in cells incubated with protamine and LNPs containing YSK05 was three times greater than that in cells without protamine, proving that the addition of exogenous protamine can increase the efficiency of LNP endosome escape.143 Several other methods for endosomal escape using siRNA as a delivery target have also been reported. Cell-penetrating peptides (CPPs) are one of the techniques used to increase the level of intracellular escape. After the addition of CPP, the first step in the cell cycle is binding to the sulfated heparin proteoglycan on the cell surface, which allows siRNA to enter the cell through nonendocytosis.144 Kim et al. recently attempted to add biocompatible polyhistidine (pHis) to traditional LNPs to enhance endosome escape and observed good results in siRNA delivery.145 This solution is achieved not by promoting membrane phase transition but by the proton sponge effect generated by the aggregation of a large number of nitrogen atoms through histidine polymerization.

4.3. mRNA-LNP Stability

Encapsulation of LNPs prevents premature degradation of mRNAs in vivo and enhances the in vivo stability of mRNAs.146 Storage stability is also a necessary consideration in the design of mRNA vaccines due to the time required for transport, delivery, and community distribution. To distribute the vaccine efficiently worldwide, it should have a sufficiently long shelf life, preferably at temperatures consistent with those of conventional vaccines (2–8 °C) or higher. While most conventional vaccines can be stored in a refrigerator at 4 °C for more than 6 months, mRNA-LNP vaccines require refrigerated cold-chain transport. mRNA-1273 can be stored at temperatures between −15 and −25 °C, whereas BNT162b2 can be stored at temperatures between −60 and −90 °C.147,148 Very low storage temperatures have become a major obstacle for vaccine distribution, especially in countries with poor infrastructure. However, the mRNA-LNP stability at nonrefrigerated temperatures needs to be further improved.

4.3.1. Adding Protective Agents

In contrast to the harsh storage conditions used for mRNA-1273 and BNT162b2, Onpattro (Patisaran), a siRNA-LNP drug product, can be stored for up to 3 years between 2 and 8 °C.149 The ionizable cationic lipid that makes up the LNPs is DLin-MC3-DMA. dLin-MC3-DMA: DSPC: cholesterol: PEG2000-C-DMG = 50: 10: 38.5: 1.5; the composition of this LNP is similar to that of the LNPs of the two neo-crowned mRNA vaccines. Based on these data, it was hypothesized that mRNA is the destabilizing factor in overall mRNA-LNPs and determines the storage conditions of mRNA vaccines. Moderna uses Tris-HCL as a stabilizer of mRNA-1273 to stabilize the mRNA,148 and other nonreducing free radical scavengers could perhaps be used as well, but the extent to which this approach alters the storage stability of the mRNA-LNP above 0 °C has not yet been determined.

4.3.2. Lyophilization

Since mRNA-LNPs are readily degraded in water, lyophilization may be an effective way to store mRNAs at relatively high temperatures. The lyophilized form of Pfizer’s mRNA-based cytomegalovirus vaccine (mRNA-1647) was tested in phase 2 clinical trials. It has a shelf life of up to 18 months at 5 °C.148 Freeze-drying is widely used for live attenuated virus vaccines.149a Its use in naked mRNA preparations has also been investigated, demonstrating its applicability and beneficial effects on the mRNA stability. Hiromi et al. demonstrated that the use of freeze-drying to store mRNA vaccines resulted in essentially unchanged vaccine potency after 24 weeks of storage at 4 °C.150 Thus, lyophilization may be a possible method for increasing the stability of mRNA–LNP combinations, thus allowing higher storage temperatures of mRNA vaccines. However, lyophilization is also a time-consuming and labor-intensive process, and alternative drying techniques should be considered.

4.4. Adverse Effects

Anaphylactic reactions triggered by vaccination with the COVID-19 mRNA are rare but not unknown. Between 14 and 23 December 2020, 175 patients with severe anaphylactic reactions were reported to the Vaccine Adverse Event Reporting System (VAERS) after 893,360,19 people received the first dose of BNT162b2.151 The first dose of mRNA-1273 was initiated on 21 December 2020, and between 21 December 2020 and 10 January 2021, 10 anaphylactic reactions were identified out of 4,041,396 vaccines.152 However, neither the mRNA nor the excipients used in both vaccines (BNT162b2: sucrose, sodium chloride, potassium chloride, disodium phosphate dihydrate, potassium dihydrogen phosphate, and water) were used for injection. mRNA-1273: aminoglutethimide, aminoglutethimide hydrochloride, acetic acid, sodium acetate, and sucrose) constitute allergens. When using polyethylene glycolated nanomedicines (e.g., polyethylene glycol), individuals experiencing allergic reactions had higher titers of anti-PEG IgG, while individuals with high titers of anti-PEG IgG did not all experience allergic reactions.153 It is hypothesized that the nature of the anti-PEG IgG agent may have some influence on this phenomenon as well as individual differences in antibody sensitivity. It has also been reported that anaphylactic reactions may be associated with the preexistence of anti-PEG IgE,154 but PEG is widely available for use in everyday hygiene and cosmetics, and these products do not cause anaphylactic reactions. Overall, the causes of allergic reactions caused by mRNA vaccines are unclear, and further studies are needed to understand the causes of allergic reactions, which are also necessary for the establishment of mRNA vaccines.

5. Other mRNA Delivery Systems

While working on improving LNPs, scientists have also invested their efforts in other delivery systems. Different chemical and biological materials based on polymers, nucleic acids, peptides, proteins, biofilms, metals, and inorganic materials have been developed for mRNA delivery. These delivery systems were either developed at the same time as the LNPs or were designed to overcome some of the limitations of the LNPs.

5.1. Polymer Delivery Systems

Polymer delivery systems, although far less clinically advanced than LNPs, are also an important class of mRNA carriers. systems are also an important class of mRNA carriers. Cationic/ionizable polymers with different chemical structures, including polyethyleneimine (PEI), polyesters, poly(amino acids), polyolefins, polysaccharides, cationic/ionizable polymers with different chemical structures, and polysaccharides), and cationic/ionizable polymers with different topologies, including linear polymers, dendrimers, hyperbranched polymers, and polysaccharides, were studied for mRNA delivery.155,156 In our recent study, we synthesized a set of alternating hydroxy-tertiary amine (PHTA)-based copolymers, PHTA-Cn, and identified the lead polymer nanocarrier PHTA-C18, which successfully delivered mRNA-based cancer vaccines in vivo and induced effective antitumor cellular immune responses.157 Notably, unlike conventional LNPs, which induce an inflammatory response to a different extent, PHTA-C18-based polymeric nanocarriers trigger only negligible inflammatory side effects in vivo, which provides a promising approach for constructing nanocarriers.

5.2. Inorganic Material-Based Delivery Systems

Inorganic materials have been used to synthesize nanostructured materials for nucleic acid delivery applications. These inorganic NPs have been precisely formulated and can be designed to have a variety of sizes, structures, and geometries. Common inorganic NPs include calcium phosphate and mesoporous silica. Huang et al. designed tumor-targeted lipid-dendritic polymer-calcium phosphate (TT-LDCP) nanoparticles (NPs) and delivered siRNA targeting plasmid DNA encoding the immune checkpoint ligand PD-L1 and immunostimulatory IL-2 to hepatocellular carcinoma (HCC) cells, which increased tumor infiltration of CD8 T cells and inhibited HCC progression.158 Xu et al. synthesized biodegradable mesoporous silica nanoparticles (MSNs) and coloaded multiple neoantigenic peptides, CpG oligodeoxynucleotide adjuvants, and the photosensitizer chlorin e6 into MSNs, which triggered neoantigen specific, tumor-infiltrating cytotoxic T-cell lymphocytes after IV administration, with strong antitumor efficacy.159 Zhang et al. applied an mRNA-MSN vaccine preparation consisting of naked mRNAs encoding OVA and granulocyte macrophage colony-stimulating factor, as well as MSNs, to a xenografted E.G7-OVA prophylactic tumor model and showed a very strong inhibitory effect on the tumor.160

5.3. Peptide-Based Delivery Systems

CPPs can also cross cell membranes and efficiently deliver nucleic acids. Lou et al. developed a method for formulating mRNA polymers functionalized with GALA that showed a high transfection efficiency and no cytotoxicity. An arginine-rich CPP variant, RALA, has been developed for mRNA vaccine delivery.161

5.4. Biological-Membrane-Based Delivery Systems

Various biofilm-based delivery systems, such as extracellular vesicles162 (EVs) (e.g., exosomes), have been used for mRNA delivery. The most commonly used EVs are exosomes 30–100 nm in length.144 The initial discovery of nucleic acids in exosomes163 suggested that EVs have the potential to be loaded with nucleic acids. Transmembrane proteins and lipids on the surface of EVs from host cells can release signals to evade phagocytosis164 and cross cellular barriers, which is an advantage that makes EVs unique to EVs compared to other delivery systems, including LNPs.165 You et al. produced human dermal fibroblast-based EVs by cell nanocutting for the delivery of mRNAs encoding extracellular matrix α1 type I collagen and successfully replenished dermal collagen in mice. Popowski et al. developed inhalable lung-derived exosomes that showed better tissue distribution than LNPs when delivering mRNA to the lungs of rodents and nonhuman primates.166,167 Ma et al. utilized a mixture of EV-loaded mRNAs of human vascular endothelial growth factor A (VEGF-A) and human bone morphogenetic protein 2 (BMP-2) to achieve efficient bone regeneration in rats.168 Exosomes are well tolerated after repeated administration and have been widely used as nanocarriers for the delivery of various therapeutic agents, including mRNAs.169

Moreover, EVs show great potential for mRNA delivery due to their excellent biocompatibility and stability and ability to cross biological barriers. Bioengineered exosomes show greater potential than natural exosomes for disease treatment due to their improved in vivo performance. However, unmodified EVs tend to accumulate in the liver, kidney, and spleen, possibly leading to insufficient mRNA delivery to the target site.170,171 To address this problem, scientists have generated bioengineered natural EVs by inserting tissue-specific coding sequences or combining them with peptides, but the production of bioengineered EVs is expensive and time-consuming. This may also explain why few clinical applications of EV-based mRNA products have been reported thus far.

5.5. Hybrid Delivery Systems

Lipid–polymer hybrid carriers, also known as lipid polymers (LPPs), are a promising class of organic–organic hybrid carriers in which the lipid component can be cationic/ionizable lipids, phospholipids, cholesterol, or PEG–lipids and the polymer component can be polylactic–coglycolic acid (PLGA) or dendritic polymers. Supe et al. used LPP-loaded human antigen R (HuR) siRNA to effectively alleviate diabetic retinopathy (DR) in rats.172 Persano et al. used LPP loaded with OVA mRNA to reduce B16-OVA-based tumor nodules by more than 90% in mice after injection.173 Biochemical hybrid supports allow for the relatively easy and precise synthesis of chemical carriers with good biocompatibility and modification targeting ability. One hybridization strategy is to prepare synthetic NPs for the encapsulation of mRNA vectors; for example, Liu et al. prepared ABNP-mRNA biomimetic NPs by fusing mRNA-PEI/poly(l-lysine) complexes with erythrocyte membranes with apolipoprotein E (ApoE), enhancing blood–brain barrier (BBB) penetration.174 In addition, Wu et al. designed folate-modified exosome-liposome hybrid nanoparticles loaded with ALKBH5 mRNA to inhibit disease progression in a preclinical colorectal cancer (CRC) model by regulating the ALKBH5/JMJD8/PKM2 axis and inhibiting glycolysis.175 The use of an mRNA hybrid delivery system has gradually emerged, and this approach has become a promising mRNA delivery method.

6. Conclusion

The successful application of mRNA vaccines (against COVID-19) has led to the emergence of a new intersection between nanotechnology and the infectious disease vaccine industry for the treatment of many different diseases, including infections and cancers, among others, opening up a potential avenue for the protection of human health. However, as a new research direction, there are still many challenges to overcome. The properties, of LNPs, such as particle size, morphology, and surface properties, are strongly influenced by lipid structure and composition, which can affect the in vivo distribution, release efficiency, and storage stability of mRNA-LNPs. Scientists from different fields around the world are working together to address the issues of hepatic enrichment and insufficient in vivo escape in the application of LNPs. Scientists have used a number of strategies to achieve mRNA-LNP enrichment in target tissues and target cells, including (1) altering the structure or ratio of lipids, including ionizable lipids, cholesterol, and polyethylene glycolated lipids; (2) adding components other than the traditional four components to alter LNP properties; and (3) altering the mode of inoculation. All of these factors are altered to increase the interaction with different target organs or cells to some extent, and additional studies are needed to achieve complete organ or cell targeting. Regarding endosomal escape, altering the structure of lipids to allow better fusion of LNPs with endosomal membranes and utilizing a charge-based pH-sensitive approach to facilitate endosomal escape will be the focus of future LNP research and design. The finished mRNA-LNPs are currently licensed with specific protectants to increase their stability at common temperatures, which could be a more promising storage option if the time-consuming and expensive issue of lyophilization can be resolved. In addition, some discussions on other delivery systems, especially EVs, which have their own advantages in terms of biocompatibility and permeability and have the potential to achieve specific cellular targeting through surface-modified ligands, are also presented in this paper; however, if these systems are combined with the advantages of LNPs, then these systems could lead to a significant boost in the development of nucleic acid and drug delivery. Research on LNPs and other delivery systems will continue, and these steadily advancing research advances have led to a steady increase in the use of mRNA delivery systems.

Acknowledgments

We thank Dr Yimeng An of Tsinghua University/Peking Union Medical College for her assistance with the revision and Dr Feng Shi of the University of Hong Kong for providing the molecular formula in Figure 4.

Author Contributions

Investigation, Xinyu. Zhang; resources, Zehua, Zhou; writing—original draft preparation, Xinyu. Zhang; writing—review and editing, Xinyu. Zhang; supervision, Yuanfang. Li; funding acquisition, Zehua. Zhou. All the authors have read and agreed to the published version of the manuscript.

This research was funded by Scientific research project of Tianjin Municipal Commission of Education (grant number 2023KJ138), and Scientific research project of Tianjin Municipal Commission of Education (grant number 2023KJ138).

The authors declare no competing financial interest.

References

  1. Wolff J. A.; Malone R. W.; Williams P.; Chong W.; Acsadi G.; Jani A.; Felgner P. L. Direct gene transfer into mouse muscle in vivo. Science 1990, 247 (4949), 1465–1468. 10.1126/science.1690918. [DOI] [PubMed] [Google Scholar]
  2. Martinon F.; Krishnan S.; Lenzen G.; Magné R.; Gomard E.; Guillet J. G.; Lévy J. P.; Meulien P. Induction of virus-specific cytotoxic T lymphocytes in vivo by liposome-entrapped mRNA. Eur. J. Immunol. 1993, 23 (7), 1719–22. 10.1002/eji.1830230749. [DOI] [PubMed] [Google Scholar]
  3. Thi T. T. H.; Suys E. J. A.; Lee J. S.; Nguyen D. H.; Park K. D.; Truong N. P. Lipid-Based Nanoparticles in the Clinic and Clinical Trials: From Cancer Nanomedicine to COVID-19 Vaccines. Vaccines (Basel) 2021, 9 (4), 359. 10.3390/vaccines9040359. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Aviv H.; Voloch Z.; Bastos R.; Levy S. Biosynthesis and stability of globin mRNA in cultured erythroleukemic Friend cells. Cell 1976, 8 (4), 495–503. 10.1016/0092-8674(76)90217-8. [DOI] [PubMed] [Google Scholar]
  5. Luo Y.; Na Z.; Slavoff S. A. P-Bodies: Composition, Properties, and Functions. Biochemistry 2018, 57 (17), 2424–2431. 10.1021/acs.biochem.7b01162. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Ross J.; Sullivan T. D. Half-lives of beta and gamma globin messenger RNAs and of protein synthetic capacity in cultured human reticulocytes. Blood 1985, 66 (5), 1149–1154. 10.1182/blood.V66.5.1149.bloodjournal6651149. [DOI] [PubMed] [Google Scholar]
  7. Karikó K.; Buckstein M.; Ni H.; Weissman D. Suppression of RNA recognition by Toll-like receptors: the impact of nucleoside modification and the evolutionary origin of RNA. Immunity 2005, 23 (2), 165–75. 10.1016/j.immuni.2005.06.008. [DOI] [PubMed] [Google Scholar]
  8. Chou L. Y.; Ming K.; Chan W. C. Strategies for the intracellular delivery of nanoparticles. Chem. Soc. Rev. 2011, 40 (1), 233–45. 10.1039/C0CS00003E. [DOI] [PubMed] [Google Scholar]
  9. Lakhal S.; Wood M. J. Exosome nanotechnology: an emerging paradigm shift in drug delivery: exploitation of exosome nanovesicles for systemic in vivo delivery of RNAi heralds new horizons for drug delivery across biological barriers. Bioessays. 2011, 33 (10), 737–41. 10.1002/bies.201100076. [DOI] [PubMed] [Google Scholar]
  10. Hočevar S.; Milošević A.; Rodriguez-Lorenzo L.; Ackermann-Hirschi L.; Mottas I.; Petri-Fink A.; Rothen-Rutishauser B.; Bourquin C.; Clift M. J. D. Polymer-Coated Gold Nanospheres Do Not Impair the Innate Immune Function of Human B Lymphocytes in Vitro. ACS Nano 2019, 13 (6), 6790–6800. 10.1021/acsnano.9b01492. [DOI] [PubMed] [Google Scholar]
  11. Ibba M. L.; Ciccone G.; Esposito C. L.; Catuogno S.; Giangrande P. H. Advances in mRNA nonviral delivery approaches. Adv. Drug Deliv Rev. 2021, 177, 113930 10.1016/j.addr.2021.113930. [DOI] [PubMed] [Google Scholar]
  12. Tenchov R.; Bird R.; Curtze A. E.; Zhou Q. Lipid Nanoparticles—From Liposomes to mRNA Vaccine Delivery, a Landscape of Research Diversity and Advancement. ACS Nano 2021, 15 (11), 16982–17015. 10.1021/acsnano.1c04996. [DOI] [PubMed] [Google Scholar]
  13. Bally M.; Bailey K.; Sugihara K.; Grieshaber D.; Vörös J.; Städler B. Liposome and lipid bilayer arrays toward biosensing applications. Small 2010, 6 (22), 2481–97. 10.1002/smll.201000644. [DOI] [PubMed] [Google Scholar]
  14. Das S. S.; Bharadwaj P.; Bilal M.; Barani M.; Rahdar A.; Taboada P.; Bungau S.; Kyzas G. Z. Stimuli-Responsive Polymeric Nanocarriers for Drug Delivery, Imaging, and Theragnosis. Polymers (Basel) 2020, 12 (6), 1397. 10.3390/polym12061397. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Choi B.; Choudhary M. C.; Regan J.; Sparks J. A.; Padera R. F.; Qiu X.; Solomon I. H.; Kuo H. H.; Boucau J.; Bowman K.; Adhikari U. D.; Winkler M. L.; Mueller A. A.; Hsu T. Y.; Desjardins M.; Baden L. R.; Chan B. T.; Walker B. D.; Lichterfeld M.; Brigl M.; Kwon D. S.; Kanjilal S.; Richardson E. T.; Jonsson A. H.; Alter G.; Barczak A. K.; Hanage W. P.; Yu X. G.; Gaiha G. D.; Seaman M. S.; Cernadas M.; Li J. Z. Persistence and Evolution of SARS-CoV-2 in an Immunocompromised Host. N Engl J. Med. 2020, 383 (23), 2291–2293. 10.1056/NEJMc2031364. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Anderson E. J.; Rouphael N. G.; Widge A. T.; Jackson L. A.; Roberts P. C.; Makhene M.; Chappell J. D.; Denison M. R.; Stevens L. J.; Pruijssers A. J.; McDermott A. B.; Flach B.; Lin B. C.; Doria-Rose N. A.; O’Dell S.; Schmidt S. D.; Corbett K. S.; Swanson P. A.; Padilla M.; Neuzil K. M.; Bennett H.; Leav B.; Makowski M.; Albert J.; Cross K.; Edara V. V.; Floyd K.; Suthar M. S.; Martinez D. R.; Baric R.; Buchanan W.; Luke C. J.; Phadke V. K.; Rostad C. A.; Ledgerwood J. E.; Graham B. S.; Beigel J. H. Safety and Immunogenicity of SARS-CoV-2 mRNA-1273 Vaccine in Older Adults. N Engl J. Med. 2020, 383 (25), 2427–2438. 10.1056/NEJMoa2028436. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Sahin U.; Karikó K.; Türeci Ö. mRNA-based therapeutics–developing a new class of drugs. Nat. Rev. Drug Discovery 2014, 13 (10), 759–80. 10.1038/nrd4278. [DOI] [PubMed] [Google Scholar]
  18. Akinc A.; Maier M. A.; Manoharan M.; Fitzgerald K.; Jayaraman M.; Barros S.; Ansell S.; Du X.; Hope M. J.; Madden T. D.; Mui B. L.; Semple S. C.; Tam Y. K.; Ciufolini M.; Witzigmann D.; Kulkarni J. A.; van der Meel R.; Cullis P. R. The Onpattro story and the clinical translation of nanomedicines containing nucleic acid-based drugs. Nat. Nanotechnol. 2019, 14 (12), 1084–1087. 10.1038/s41565-019-0591-y. [DOI] [PubMed] [Google Scholar]
  19. Polack F. P.; Thomas S. J.; Kitchin N.; Absalon J.; Gurtman A.; Lockhart S.; Perez J. L.; Perez Marc G.; Moreira E. D.; Zerbini C.; Bailey R.; Swanson K. A.; Roychoudhury S.; Koury K.; Li P.; Kalina W. V.; Cooper D.; Frenck R. W.; Hammitt L. L.; Tureci O.; Nell H.; Schaefer A.; Unal S.; Tresnan D. B.; Mather S.; Dormitzer P. R.; Sahin U.; Jansen K. U.; Gruber W. C. Safety and Efficacy of the BNT162b2 mRNA Covid-19 Vaccine. N Engl J. Med. 2020, 383 (27), 2603–2615. 10.1056/NEJMoa2034577. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. Hou X.; Zaks T.; Langer R.; Dong Y. Lipid nanoparticles for mRNA delivery. Nat. Rev. Mater. 2021, 6 (12), 1078–1094. 10.1038/s41578-021-00358-0. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Ramachandran S.; Satapathy S. R.; Dutta T. Delivery Strategies for mRNA Vaccines. Pharmaceut Med. 2022, 36 (1), 11–20. 10.1007/s40290-021-00417-5. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Sabnis S.; Kumarasinghe E. S.; Salerno T.; Mihai C.; Ketova T.; Senn J. J.; Lynn A.; Bulychev A.; McFadyen I.; Chan J.; Almarsson Ö; Stanton M. G.; Benenato K. E. A Novel Amino Lipid Series for mRNA Delivery: Improved Endosomal Escape and Sustained Pharmacology and Safety in Nonhuman Primates. Mol. Ther. 2018, 26 (6), 1509–1519. 10.1016/j.ymthe.2018.03.010. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Pardi N.; Hogan M. J.; Porter F. W.; Weissman D. mRNA vaccines – a new era in vaccinology. Nat. Rev. Drug Discovery 2018, 17 (4), 261–279. 10.1038/nrd.2017.243. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Leung A. K.; Hafez I. M.; Baoukina S.; Belliveau N. M.; Zhigaltsev I. V.; Afshinmanesh E.; Tieleman D. P.; Hansen C. L.; Hope M. J.; Cullis P. R. Lipid Nanoparticles Containing siRNA Synthesized by Microfluidic Mixing Exhibit an Electron-Dense Nanostructured Core. J. Phys. Chem. C Nanomater Interfaces. 2012, 116 (34), 18440–18450. 10.1021/jp303267y. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Knop K.; Hoogenboom R.; Fischer D.; Schubert U. S. Poly(ethylene glycol) in drug delivery: pros and cons as well as potential alternatives. Angew. Chem., Int. Ed. Engl. 2010, 49 (36), 6288–308. 10.1002/anie.200902672. [DOI] [PubMed] [Google Scholar]
  26. Zhu X.; Tao W.; Liu D.; Wu J.; Guo Z.; Ji X.; Bharwani Z.; Zhao L.; Zhao X.; Farokhzad O. C.; Shi J. Surface De-PEGylation Controls Nanoparticle-Mediated siRNA Delivery In Vitro and In Vivo. Theranostics 2017, 7 (7), 1990–2002. 10.7150/thno.18136. [DOI] [PMC free article] [PubMed] [Google Scholar]
  27. Cheng X.; Lee R. J. The role of helper lipids in lipid nanoparticles (LNPs) designed for oligonucleotide delivery. Adv. Drug Deliv Rev. 2016, 99 (Pt A), 129–137. 10.1016/j.addr.2016.01.022. [DOI] [PubMed] [Google Scholar]
  28. Eygeris Y.; Patel S.; Jozic A.; Sahay G. Deconvoluting Lipid Nanoparticle Structure for Messenger RNA Delivery. Nano Lett. 2020, 20 (6), 4543–4549. 10.1021/acs.nanolett.0c01386. [DOI] [PMC free article] [PubMed] [Google Scholar]
  29. Nature Communications at Ten. Nat. Commun. 2020, 11( (1), ), 1812. 10.1038/s41467-020-15592-3. [DOI] [PMC free article] [PubMed] [Google Scholar]
  30. Verma M.; Ozer I.; Xie W.; Gallagher R.; Teixeira A.; Choy M. The landscape for lipid-nanoparticle-based genomic medicines. Nat. Rev. Drug Discovery 2023, 22 (5), 349–350. 10.1038/d41573-023-00002-2. [DOI] [PubMed] [Google Scholar]
  31. Zhang Y. N.; Poon W.; Tavares A. J.; McGilvray I. D.; Chan W. C. W. Nanoparticle-liver interactions: Cellular uptake and hepatobiliary elimination. J. Controlled Release 2016, 240, 332–348. 10.1016/j.jconrel.2016.01.020. [DOI] [PubMed] [Google Scholar]
  32. Soutschek J.; Akinc A.; Bramlage B.; Charisse K.; Constien R.; Donoghue M.; Elbashir S.; Geick A.; Hadwiger P.; Harborth J.; John M.; Kesavan V.; Lavine G.; Pandey R. K.; Racie T.; Rajeev K. G.; Röhl I.; Toudjarska I.; Wang G.; Wuschko S.; Bumcrot D.; Koteliansky V.; Limmer S.; Manoharan M.; Vornlocher H. P. Therapeutic silencing of an endogenous gene by systemic administration of modified siRNAs. Nature 2004, 432 (7014), 173–8. 10.1038/nature03121. [DOI] [PubMed] [Google Scholar]
  33. Schlich M.; Palomba R.; Costabile G.; Mizrahy S.; Pannuzzo M.; Peer D.; Decuzzi P. Cytosolic delivery of nucleic acids: The case of ionizable lipid nanoparticles. Bioeng Transl Med. 2021, 6 (2), e10213 10.1002/btm2.10213. [DOI] [PMC free article] [PubMed] [Google Scholar]
  34. Weissman D.; Ni H.; Scales D.; Dude A.; Capodici J.; McGibney K.; Abdool A.; Isaacs S. N.; Cannon G.; Karikó K. HIV gag mRNA transfection of dendritic cells (DC) delivers encoded antigen to MHC class I and II molecules, causes DC maturation, and induces a potent human in vitro primary immune response. J. Immunol. 2000, 165 (8), 4710–7. 10.4049/jimmunol.165.8.4710. [DOI] [PubMed] [Google Scholar]
  35. Van Gulck E.; Vlieghe E.; Vekemans M.; Van Tendeloo V. F.; Van De Velde A.; Smits E.; Anguille S.; Cools N.; Goossens H.; Mertens L.; De Haes W.; Wong J.; Florence E.; Vanham G.; Berneman Z. N. mRNA-based dendritic cell vaccination induces potent antiviral T-cell responses in HIV-1-infected patients. AIDS. 2012, 26 (4), F1–12. 10.1097/QAD.0b013e32834f33e8. [DOI] [PubMed] [Google Scholar]
  36. Aligholipour Farzani T.; Földes K.; Ergünay K.; Gurdal H.; Bastug A.; Ozkul A. Immunological Analysis of a CCHFV mRNA Vaccine Candidate in Mouse Models. Vaccines (Basel) 2019, 7 (3), 115. 10.3390/vaccines7030115. [DOI] [PMC free article] [PubMed] [Google Scholar]
  37. Karam M.; Daoud G. mRNA vaccines: Past, present, future. Asian J. Pharm. Sci. 2022, 17 (4), 491–522. 10.1016/j.ajps.2022.05.003. [DOI] [PMC free article] [PubMed] [Google Scholar]
  38. Selby L. I.; Cortez-Jugo C. M.; Such G. K.; Johnston A. P. R. Nanoescapology: progress toward understanding the endosomal escape of polymeric nanoparticles. Wiley Interdiscip Rev. Nanomed Nanobiotechnol 2017, 9 (5), e1452 10.1002/wnan.1452. [DOI] [PubMed] [Google Scholar]
  39. Kim J.; Eygeris Y.; Gupta M.; Sahay G. Self-assembled mRNA vaccines. Adv. Drug Deliv Rev. 2021, 170, 83–112. 10.1016/j.addr.2020.12.014. [DOI] [PMC free article] [PubMed] [Google Scholar]
  40. Baden L. R.; El Sahly H. M.; Essink B.; Kotloff K.; Frey S.; Novak R.; Diemert D.; Spector S. A.; Rouphael N.; Creech C. B.; McGettigan J.; Khetan S.; Segall N.; Solis J.; Brosz A.; Fierro C.; Schwartz H.; Neuzil K.; Corey L.; Gilbert P.; Janes H.; Follmann D.; Marovich M.; Mascola J.; Polakowski L.; Ledgerwood J.; Graham B. S.; Bennett H.; Pajon R.; Knightly C.; Leav B.; Deng W.; Zhou H.; Han S.; Ivarsson M.; Miller J.; Zaks T. Efficacy and Safety of the mRNA-1273 SARS-CoV-2 Vaccine. N Engl J. Med. 2021, 384 (5), 403–416. 10.1056/NEJMoa2035389. [DOI] [PMC free article] [PubMed] [Google Scholar]
  41. Nanduri S.; Pilishvili T.; Derado G.; Soe M. M.; Dollard P.; Wu H.; Li Q.; Bagchi S.; Dubendris H.; Link-Gelles R.; Jernigan J. A.; Budnitz D.; Bell J.; Benin A.; Shang N.; Edwards J. R.; Verani J. R.; Schrag S. J. Effectiveness of Pfizer-BioNTech and Moderna Vaccines in Preventing SARS-CoV-2 Infection Among Nursing Home Residents Before and During Widespread Circulation of the SARS-CoV-2 B.1.617.2 (Delta) Variant – National Healthcare Safety Network, March 1-August 1, 2021. MMWR Morb Mortal Wkly Rep. 2021, 70 (34), 1163–1166. 10.15585/mmwr.mm7034e3. [DOI] [PMC free article] [PubMed] [Google Scholar]
  42. Richner J. M.; Himansu S.; Dowd K. A.; Butler S. L.; Salazar V.; Fox J. M.; Julander J. G.; Tang W. W.; Shresta S.; Pierson T. C.; Ciaramella G.; Diamond M. S. Modified mRNA Vaccines Protect against Zika Virus Infection. Cell. 2017, 168 (6), 1114–1125.e10. 10.1016/j.cell.2017.02.017. [DOI] [PMC free article] [PubMed] [Google Scholar]; Erratum. Cell 2017, 169, 1176. 10.1016/j.cell.2017.03.016
  43. Bahl K.; Senn J. J.; Yuzhakov O.; Bulychev A.; Brito L. A.; Hassett K. J.; Laska M. E.; Smith M.; Almarsson Ö; Thompson J.; Ribeiro A. M.; Watson M.; Zaks T.; Ciaramella G. Preclinical and Clinical Demonstration of Immunogenicity by mRNA Vaccines against H10N8 and H7N9 Influenza Viruses. Mol. Ther. 2017, 25 (6), 1316–1327. 10.1016/j.ymthe.2017.03.035. [DOI] [PMC free article] [PubMed] [Google Scholar]
  44. Meyer M.; Huang E.; Yuzhakov O.; Ramanathan P.; Ciaramella G.; Bukreyev A. Modified mRNA-Based Vaccines Elicit Robust Immune Responses and Protect Guinea Pigs From Ebola Virus Disease. J. Infect Dis. 2018, 217 (3), 451–455. 10.1093/infdis/jix592. [DOI] [PMC free article] [PubMed] [Google Scholar]
  45. Pardi N.; LaBranche C. C.; Ferrari G.; Cain D. W.; Tombácz I.; Parks R. J.; Muramatsu H.; Mui B. L.; Tam Y. K.; Karikó K.; Polacino P.; Barbosa C. J.; Madden T. D.; Hope M. J.; Haynes B. F.; Montefiori D. C.; Hu S. L.; Weissman D. Characterization of HIV-1 Nucleoside-Modified mRNA Vaccines in Rabbits and Rhesus Macaques. Mol. Ther Nucleic Acids. 2019, 15, 36–47. 10.1016/j.omtn.2019.03.003. [DOI] [PMC free article] [PubMed] [Google Scholar]
  46. Lo M. K.; Spengler J. R.; Welch S. R.; Harmon J. R.; Coleman-McCray J. D.; Scholte F. E. M.; Shrivastava-Ranjan P.; Montgomery J. M.; Nichol S. T.; Weissman D.; Spiropoulou C. F. Evaluation of a Single-Dose Nucleoside-Modified Messenger RNA Vaccine Encoding Hendra Virus-Soluble Glycoprotein Against Lethal Nipah virus Challenge in Syrian Hamsters. J. Infect Dis. 2020, 221 (Suppl 4), S493–S498. 10.1093/infdis/jiz553. [DOI] [PMC free article] [PubMed] [Google Scholar]
  47. Nelson C. S.; Jenks J. A.; Pardi N.; Goodwin M.; Roark H.; Edwards W.; McLellan J. S.; Pollara J.; Weissman D.; Permar S. R. Human Cytomegalovirus Glycoprotein B Nucleoside-Modified mRNA Vaccine Elicits Antibody Responses with Greater Durability and Breadth than MF59-Adjuvanted gB Protein Immunization. J. Virol. 2020, 94 (9), e00186–20. 10.1128/JVI.00186-20. [DOI] [PMC free article] [PubMed] [Google Scholar]
  48. Aliprantis A. O.; Shaw C. A.; Griffin P.; Farinola N.; Railkar R. A.; Cao X.; Liu W.; Sachs J. R.; Swenson C. J.; Lee H.; Cox K. S.; Spellman D. S.; Winstead C. J.; Smolenov I.; Lai E.; Zaks T.; Espeseth A. S.; Panther L. A phase 1, randomized, placebo-controlled study to evaluate the safety and immunogenicity of an mRNA-based RSV prefusion F protein vaccine in healthy younger and older adults. Hum Vaccin Immunother. 2021, 17 (5), 1248–1261. 10.1080/21645515.2020.1829899. [DOI] [PMC free article] [PubMed] [Google Scholar]
  49. Espeseth A. S.; Cejas P. J.; Citron M. P.; Wang D.; DiStefano D. J.; Callahan C.; Donnell G. O.; Galli J. D.; Swoyer R.; Touch S.; Wen Z.; Antonello J.; Zhang L.; Flynn J. A.; Cox K. S.; Freed D. C.; Vora K. A.; Bahl K.; Latham A. H.; Smith J. S.; Gindy M. E.; Ciaramella G.; Hazuda D.; Shaw C. A.; Bett A. J. Modified mRNA/lipid nanoparticle-based vaccines expressing respiratory syncytial virus F protein variants are immunogenic and protective in rodent models of RSV infection. NPJ. Vaccines. 2020, 5 (1), 16. 10.1038/s41541-020-0163-z. [DOI] [PMC free article] [PubMed] [Google Scholar]
  50. Aldrich C.; Leroux-Roels I.; Huang K. B.; Bica M. A.; Loeliger E.; Schoenborn-Kellenberger O.; Walz L.; Leroux-Roels G.; von Sonnenburg F.; Oostvogels L. Proof-of-concept of a low-dose unmodified mRNA-based rabies vaccine formulated with lipid nanoparticles in human volunteers: A phase 1 trial. Vaccine 2021, 39 (8), 1310–1318. 10.1016/j.vaccine.2020.12.070. [DOI] [PMC free article] [PubMed] [Google Scholar]
  51. Laumont C. M.; Vincent K.; Hesnard L.; Audemard É; Bonneil É; Laverdure J. P.; Gendron P.; Courcelles M.; Hardy M. P.; Côté C.; Durette C.; St-Pierre C.; Benhammadi M.; Lanoix J.; Vobecky S.; Haddad E.; Lemieux S.; Thibault P.; Perreault C. Noncoding regions are the main source of targetable tumor-specific antigens. Sci. Transl Med. 2018, 10 (470), eaau5516 10.1126/scitranslmed.aau5516. [DOI] [PubMed] [Google Scholar]
  52. Alarcon N. O.; Jaramillo M.; Mansour H. M.; Sun B. Therapeutic Cancer Vaccines-Antigen Discovery and Adjuvant Delivery Platforms. Pharmaceutics 2022, 14 (7), 1448. 10.3390/pharmaceutics14071448. [DOI] [PMC free article] [PubMed] [Google Scholar]
  53. Tatematsu M.; Funami K.; Seya T.; Matsumoto M. Extracellular RNA Sensing by Pattern Recognition Receptors. J. Innate Immun. 2018, 10, 398–406. 10.1159/000494034. [DOI] [PMC free article] [PubMed] [Google Scholar]
  54. Zhang C.; Maruggi G.; Shan H.; Li J. Advances in mRNA Vaccines for Infectious Diseases. Front. Immunol. 2019, 10, 594. 10.3389/fimmu.2019.00594. [DOI] [PMC free article] [PubMed] [Google Scholar]
  55. Iavarone C.; O’Hagan D. T.; Yu D.; Delahaye N. F.; Ulmer J. B. Mechanism of action of mRNA-based vaccines. Expert. Rev. Vaccines. 2017, 16, 871–881. 10.1080/14760584.2017.1355245. [DOI] [PubMed] [Google Scholar]
  56. Edwards D. K.; Jasny E.; Yoon H.; Horscroft N.; Schanen B.; Geter T.; Fotin-Mleczek M.; Petsch B.; Wittman V. Adjuvant effects of a sequence-engineered mRNA vaccine: Translational profiling demonstrates similar human and murine innate response. J. Transl. Med. 2017, 15, 1. 10.1186/s12967-016-1111-6. [DOI] [PMC free article] [PubMed] [Google Scholar]
  57. Oberli M. A.; Reichmuth A. M.; Dorkin J. R.; Mitchell M. J.; Fenton O. S.; Jaklenec A.; Anderson D. G.; Langer R.; Blankschtein D. Lipid Nanoparticle Assisted mRNA Delivery for Potent Cancer Immunotherapy. Nano Lett. 2017, 17 (3), 1326–1335. 10.1021/acs.nanolett.6b03329. [DOI] [PMC free article] [PubMed] [Google Scholar]
  58. Bevers S.; Kooijmans S. A.A.; Van de Velde E.; Evers M. J.W.; Seghers S.; Gitz-Francois J. J. J. M.; van Kronenburg N. C.H.; Fens M. H.A.M.; Mastrobattista E.; Hassler L.; Sork H.; Lehto T.; Ahmed K. E.; El Andaloussi S.; Fiedler K.; Breckpot K.; Maes M.; Van Hoorick D.; Bastogne T.; Schiffelers R. M.; De Koker S. mRNA-LNP vaccines tuned for systemic immunization induce strong antitumor immunity by engaging splenic immune cells. Mol. Ther. 2022, 30 (9), 3078–3094. 10.1016/j.ymthe.2022.07.007. [DOI] [PMC free article] [PubMed] [Google Scholar]
  59. mRNA Vaccine Slows Melanoma Recurrence. Cancer Discov. 2023, 13 (6), 1278. 10.1158/2159-8290.CD-NB2023-0028. [DOI] [PubMed] [Google Scholar]
  60. Sahin U.; Oehm P.; Derhovanessian E.; Jabulowsky R. A.; Vormehr M.; Gold M.; Maurus D.; Schwarck-Kokarakis D.; Kuhn A. N.; Omokoko T.; Kranz L. M.; Diken M.; Kreiter S.; Haas H.; Attig S.; Rae R.; Cuk K.; Kemmer-Brück A.; Breitkreuz A.; Tolliver C.; Caspar J.; Quinkhardt J.; Hebich L.; Stein M.; Hohberger A.; Vogler I.; Liebig I.; Renken S.; Sikorski J.; Leierer M.; Müller V.; Mitzel-Rink H.; Miederer M.; Huber C.; Grabbe S.; Utikal J.; Pinter A.; Kaufmann R.; Hassel J. C.; Loquai C.; Türeci Ö. An RNA vaccine drives immunity in checkpoint-inhibitor-treated melanoma. Nature 2020, 585 (7823), 107–12. 10.1038/s41586-020-2537-9. [DOI] [PubMed] [Google Scholar]
  61. Deng Z.; Tian Y.; Song J.; An G.; Yang P. mRNA vaccines: the dawn of a new era of cancer immunotherapy. Front Immunol 2022, 13, 887125 10.3389/fimmu.2022.887125. [DOI] [PMC free article] [PubMed] [Google Scholar]
  62. Porciuncula A.; Morgado M.; Gupta R.; Syrigos K.; Meehan R.; Zacharek S. J.; Frederick J. P.; Schalper K. A. Spatial Mapping and Immunomodulatory Role of the OX40/OX40L Pathway in Human Non-Small Cell Lung Cancer. Clin. Cancer Res. 2021, 27 (22), 6174–6183. 10.1158/1078-0432.CCR-21-0987. [DOI] [PMC free article] [PubMed] [Google Scholar]
  63. Yin H.; Kanasty R. L.; Eltoukhy A. A.; Vegas A. J.; Dorkin J. R.; Anderson D. G. Nonviral vectors for gene-based therapy. Nat. Rev. Genet. 2014, 15 (8), 541–55. 10.1038/nrg3763. [DOI] [PubMed] [Google Scholar]
  64. Dhaliwal H. K.; Fan Y.; Kim J.; Amiji M. M. Intranasal Delivery and Transfection of mRNA Therapeutics in the Brain Using Cationic Liposomes. Mol. Pharmaceutics 2020, 17 (6), 1996–2005. 10.1021/acs.molpharmaceut.0c00170. [DOI] [PubMed] [Google Scholar]
  65. Petsch B.; Schnee M.; Vogel A. B.; Lange E.; Hoffmann B.; Voss D.; Schlake T.; Thess A.; Kallen K. J.; Stitz L.; Kramps T. Protective efficacy of in vitro synthesized, specific mRNA vaccines against influenza A virus infection. Nat. Biotechnol. 2012, 30 (12), 1210–6. 10.1038/nbt.2436. [DOI] [PubMed] [Google Scholar]
  66. Chen R.; Zhang H.; Yan J.; Bryers J. D. Scaffold-mediated delivery for nonviral mRNA vaccines. Gene Ther. 2018, 25 (8), 556–567. 10.1038/s41434-018-0040-9. [DOI] [PMC free article] [PubMed] [Google Scholar]
  67. John S.; Yuzhakov O.; Woods A.; Deterling J.; Hassett K.; Shaw C. A.; Ciaramella G. Multiantigenic human cytomegalovirus mRNA vaccines that elicit potent humoral and cell-mediated immunity. Vaccine. 2018, 36 (12), 1689–1699. 10.1016/j.vaccine.2018.01.029. [DOI] [PubMed] [Google Scholar]
  68. Samaridou E.; Heyes J.; Lutwyche P. Lipid nanoparticles for nucleic acid delivery: Current perspectives. Adv. Drug Deliv Rev. 2020, 154–155, 37–63. 10.1016/j.addr.2020.06.002. [DOI] [PubMed] [Google Scholar]
  69. Hajj K.; Whitehead K. Tools for translation: nonviral materials for therapeutic mRNA delivery. Nat. Rev. Mater. 2017, 2, 17056. 10.1038/natrevmats.2017.56. [DOI] [Google Scholar]
  70. Kowalski P. S.; Rudra A.; Miao L.; Anderson D. G. Delivering the Messenger: Advances in Technologies for Therapeutic mRNA Delivery. Mol. Ther. 2019, 27 (4), 710–728. 10.1016/j.ymthe.2019.02.012. [DOI] [PMC free article] [PubMed] [Google Scholar]
  71. Ferhan A. R.; Park S.; Park H.; Tae H.; Jackman J. A.; Cho N.-J. Lipid nanoparticle technologies for nucleic acid delivery: A nanoarchitectonics perspective. Adv. Funct. Mater. 2022, 32, 2203669 10.1002/adfm.202203669. [DOI] [Google Scholar]
  72. Chaudhary N.; Weissman D.; Whitehead K. A. mRNA vaccines for infectious diseases: principles, delivery and clinical translation [published correction appears in Nat Rev Drug Discov. 2021 Sep 21;:]. Nat. Rev. Drug Discovery 2021, 20 (11), 817–838. 10.1038/s41573-021-00283-5. [DOI] [PMC free article] [PubMed] [Google Scholar]
  73. Meng C.; Chen Z.; Mai J.; Shi Q.; Tian S.; Hinkle L.; Li J.; Zhang Z.; Ramirez M.; Zhang L.; Xu Y.; Zhang J.; Pan P. Y.; Chen S. H.; Li H.; Shen H. Virus-Mimic mRNA Vaccine for Cancer Treatment. Adv. Ther (Weinh). 2021, 4 (11), 2100144 10.1002/adtp.202100144. [DOI] [PMC free article] [PubMed] [Google Scholar]
  74. Oberli M. A.; Reichmuth A. M.; Dorkin J. R.; Mitchell M. J.; Fenton O. S.; Jaklenec A.; Anderson D. G.; Langer R.; Blankschtein D. Lipid Nanoparticle Assisted mRNA Delivery for Potent Cancer Immunotherapy. Nano Lett. 2017, 17 (3), 1326–1335. 10.1021/acs.nanolett.6b03329. [DOI] [PMC free article] [PubMed] [Google Scholar]
  75. Allen R. J.; Mathew B.; Rice K. G. PEG-Peptide Inhibition of Scavenger Receptor Uptake of Nanoparticles by the Liver. Mol. Pharmaceutics 2018, 15 (9), 3881–3891. 10.1021/acs.molpharmaceut.8b00355. [DOI] [PMC free article] [PubMed] [Google Scholar]
  76. Haroon H. B.; Hunter A. C.; Farhangrazi Z. S.; Moghimi S. M. A brief history of long circulating nanoparticles. Adv. Drug Deliv Rev. 2022, 188, 114396 10.1016/j.addr.2022.114396. [DOI] [PubMed] [Google Scholar]
  77. Woodle M. C. Sterically stabilized liposome therapeutics. Adv. Drug Delivery Rev. 1995, 16 (2), 249–265. 10.1016/0169-409X(95)00028-6. [DOI] [Google Scholar]
  78. Suk J. S.; Xu Q.; Kim N.; Hanes J.; Ensign L. M. PEGylation as a strategy for improving nanoparticle-based drug and gene delivery. Adv. Drug Deliv Rev. 2016, 99 (Pt A), 28–51. 10.1016/j.addr.2015.09.012. [DOI] [PMC free article] [PubMed] [Google Scholar]
  79. Li S. D.; Huang L. Stealth nanoparticles: high density but sheddable PEG is a key for tumor targeting. J. Controlled Release 2010, 145 (3), 178–81. 10.1016/j.jconrel.2010.03.016. [DOI] [PMC free article] [PubMed] [Google Scholar]
  80. De A.; Ko Y. T. A tale of nucleic acid-ionizable lipid nanoparticles: Design and manufacturing technology and advancement. Expert Opin Drug Delivery 2023, 20 (1), 75–91. 10.1080/17425247.2023.2153832. [DOI] [PubMed] [Google Scholar]
  81. Takahashi H.; Sinoda K.; Hatta I. Effects of cholesterol on the lamellar and the inverted hexagonal phases of dielaidoylphosphatidylethanolamine. Biochim. Biophys. Acta 1996, 1289 (2), 209–16. 10.1016/0304-4165(95)00170-0. [DOI] [PubMed] [Google Scholar]
  82. Zuhorn I. S.; Bakowsky U.; Polushkin E.; Visser W. H.; Stuart M. C.; Engberts J. B.; Hoekstra D. Nonbilayer phase of lipoplex-membrane mixture determines endosomal escape of genetic cargo and transfection efficiency. Mol. Ther. 2005, 11 (5), 801–10. 10.1016/j.ymthe.2004.12.018. [DOI] [PubMed] [Google Scholar]
  83. Dobbs W.; Heinrich B.; Bourgogne C.; Donnio B.; Terazzi E.; Bonnet M. E.; Stock F.; Erbacher P.; Bolcato-Bellemin A. L.; Douce L. Mesomorphic imidazolium salts: new vectors for efficient siRNA transfection. J. Am. Chem. Soc. 2009, 131 (37), 13338–46. 10.1021/ja903028f. [DOI] [PubMed] [Google Scholar]
  84. Cui L.; Chen D.; Zhu L. Conformation transformation determined by different self-assembled phases in a DNA complex with cationic polyhedral oligomeric silsesquioxane lipid. ACS Nano 2008, 2 (5), 921–927. 10.1021/nn800177v. [DOI] [PubMed] [Google Scholar]
  85. Koiwai K.; Tokuhisa K.; Karinaga R.; Kudo Y.; Kusuki S.; Takeda Y.; Sakurai K. Transition from a normal to inverted cylinder for an amidine-bearing lipid/pDNA complex and its excellent transfection. Bioconjug Chem. 2005, 16 (6), 1349–51. 10.1021/bc050164a. [DOI] [PubMed] [Google Scholar]
  86. Smisterová J.; Wagenaar A.; Stuart M. C.; Polushkin E.; ten Brinke G.; Hulst R.; Engberts J. B.; Hoekstra D. Molecular shape of the cationic lipid controls the structure of cationic lipid/dioleylphosphatidylethanolamine-DNA complexes and the efficiency of gene delivery. J. Biol. Chem. 2001, 276 (50), 47615–22. 10.1074/jbc.M106199200. [DOI] [PubMed] [Google Scholar]
  87. Malone R. W.; Felgner P. L.; Verma I. M. Cationic liposome-mediated RNA transfection. Proc. Natl. Acad. Sci. U. S. A. 1989, 86 (16), 6077–81. 10.1073/pnas.86.16.6077. [DOI] [PMC free article] [PubMed] [Google Scholar]
  88. Cui S.; Wang Y.; Gong Y.; Lin X.; Zhao Y.; Zhi D.; Zhou Q.; Zhang S. Correlation of the cytotoxic effects of cationic lipids with their headgroups. Toxicol Res. (Camb) 2018, 7 (3), 473–479. 10.1039/C8TX00005K. [DOI] [PMC free article] [PubMed] [Google Scholar]
  89. Cullis P. R.; Hope M. J. Lipid Nanoparticle Systems for Enabling Gene Therapies. Mol. Ther. 2017, 25 (7), 1467–1475. 10.1016/j.ymthe.2017.03.013. [DOI] [PMC free article] [PubMed] [Google Scholar]
  90. Jayaraman M.; Ansell S. M.; Mui B. L.; Tam Y. K.; Chen J.; Du X.; Butler D.; Eltepu L.; Matsuda S.; Narayanannair J. K.; Rajeev K. G.; Hafez I. M.; Akinc A.; Maier M. A.; Tracy M. A.; Cullis P. R.; Madden T. D.; Manoharan M.; Hope M. J. Maximizing the potency of siRNA lipid nanoparticles for hepatic gene silencing in vivo. Angew. Chem., Int. Ed. Engl. 2012, 51 (34), 8529–33. 10.1002/anie.201203263. [DOI] [PMC free article] [PubMed] [Google Scholar]
  91. Buschmann M. D.; Carrasco M. J.; Alishetty S.; Paige M.; Alameh M. G.; Weissman D. Nanomaterial Delivery Systems for mRNA Vaccines. Vaccines (Basel) 2021, 9 (1), 65. 10.3390/vaccines9010065. [DOI] [PMC free article] [PubMed] [Google Scholar]
  92. Hassett K. J.; Benenato K. E.; Jacquinet E.; Lee A.; Woods A.; Yuzhakov O.; Himansu S.; Deterling J.; Geilich B. M.; Ketova T.; Mihai C.; Lynn A.; McFadyen I.; Moore M. J.; Senn J. J.; Stanton M. G.; Almarsson Ö; Ciaramella G.; Brito L. A. Optimization of Lipid Nanoparticles for Intramuscular Administration of mRNA Vaccines. Mol. Ther Nucleic Acids. 2019, 15, 1–11. 10.1016/j.omtn.2019.01.013. [DOI] [PMC free article] [PubMed] [Google Scholar]
  93. Hope M. J.et al. Lipid nanoparticle formulations. Patent WO-2018081480-A1, 2016.; Lipid nanoparticle formulations. PubChem Patent Summary, 2018. https://pubchem.ncbi.nlm.nih.gov/patent/WO-2018081480-A1 (accessed Sep. 15, 2023).
  94. Polack F. P.; Thomas S. J.; Kitchin N.; Absalon J.; Gurtman A.; Lockhart S.; Perez J. L.; Perez Marc G.; Moreira E. D.; Zerbini C.; Bailey R.; Swanson K. A.; Roychoudhury S.; Koury K.; Li P.; Kalina W. V.; Cooper D.; Frenck R. W.; Hammitt L. L.; Tureci O.; Nell H.; Schaefer A.; Unal S.; Tresnan D. B.; Mather S.; Dormitzer P. R.; Sahin U.; Jansen K. U.; Gruber W. C. Safety and Efficacy of the BNT162b2 mRNA Covid-19 Vaccine. N Engl J. Med. 2020, 383 (27), 2603–2615. 10.1056/NEJMoa2034577. [DOI] [PMC free article] [PubMed] [Google Scholar]
  95. DeFrancesco L. Whither COVID-19 vaccines?. Nat. Biotechnol. 2020, 38 (10), 1132–1145. 10.1038/s41587-020-0697-7. [DOI] [PMC free article] [PubMed] [Google Scholar]
  96. Yanez Arteta M.; Kjellman T.; Bartesaghi S.; Wallin S.; Wu X.; Kvist A. J.; Dabkowska A.; Székely N.; Radulescu A.; Bergenholtz J.; Lindfors L. Successful reprogramming of cellular protein production through mRNA delivered by functionalized lipid nanoparticles. Proc. Natl. Acad. Sci. U. S. A. 2018, 115 (15), E3351–E3360. 10.1073/pnas.1720542115. [DOI] [PMC free article] [PubMed] [Google Scholar]
  97. Jiang Y.; Huo S.; Mizuhara T.; Das R.; Lee Y. W.; Hou S.; Moyano D. F.; Duncan B.; Liang X. J.; Rotello V. M. The Interplay of Size and Surface Functionality on the Cellular Uptake of Sub10 nm Gold Nanoparticles. ACS Nano 2015, 9 (10), 9986–93. 10.1021/acsnano.5b03521. [DOI] [PMC free article] [PubMed] [Google Scholar]
  98. Raj S.; Khurana S.; Choudhari R.; Kesari K. K.; Kamal M. A.; Garg N.; Ruokolainen J.; Das B. C.; Kumar D. Specific targeting cancer cells with nanoparticles and drug delivery in cancer therapy. Semin Cancer Biol. 2021, 69, 166–177. 10.1016/j.semcancer.2019.11.002. [DOI] [PubMed] [Google Scholar]
  99. De Jong W. H.; Hagens W. I.; Krystek P.; Burger M. C.; Sips A. J.; Geertsma R. E. Particle size-dependent organ distribution of gold nanoparticles after intravenous administration. Biomaterials. 2008, 29 (12), 1912–9. 10.1016/j.biomaterials.2007.12.037. [DOI] [PubMed] [Google Scholar]
  100. Nakamura T.; Kawai M.; Sato Y.; Maeki M.; Tokeshi M.; Harashima H. The Effect of Size and Charge of Lipid Nanoparticles Prepared by Microfluidic Mixing on Their Lymph Node Transitivity and Distribution. Mol. Pharmaceutics 2020, 17 (3), 944–953. 10.1021/acs.molpharmaceut.9b01182. [DOI] [PubMed] [Google Scholar]
  101. Luozhong S.; Yuan Z.; Sarmiento T.; Chen Y.; Gu W.; McCurdy C.; Gao W.; Li R.; Wilkens S.; Jiang S. Phosphatidylserine Lipid Nanoparticles Promote Systemic RNA Delivery to Secondary Lymphoid Organs. Nano Lett. 2022, 22 (20), 8304–8311. 10.1021/acs.nanolett.2c03234. [DOI] [PMC free article] [PubMed] [Google Scholar]
  102. Takanashi A.; Pouton C. W.; Al-Wassiti H. Delivery and Expression of mRNA in the Secondary Lymphoid Organs Drive Immune Responses to Lipid Nanoparticle-mRNA Vaccines after Intramuscular Injection. Mol. Pharmaceutics 2023, 20 (8), 3876–3885. 10.1021/acs.molpharmaceut.2c01024. [DOI] [PMC free article] [PubMed] [Google Scholar]
  103. Okuda K.; Sato Y.; Iwakawa K.; Sasaki K.; Okabe N.; Maeki M.; Tokeshi M.; Harashima H. On the size-regulation of RNA-loaded lipid nanoparticles synthesized by microfluidic device. J. Controlled Release 2022, 348, 648–659. 10.1016/j.jconrel.2022.06.017. [DOI] [PubMed] [Google Scholar]
  104. Dilliard S. A.; Cheng Q.; Siegwart D. J. On the mechanism of tissue-specific mRNA delivery by selective organ targeting nanoparticles. Proc. Natl. Acad. Sci. U. S. A. 2021, 118 (52), e2109256118 10.1073/pnas.2109256118. [DOI] [PMC free article] [PubMed] [Google Scholar]
  105. Fenton O. S.; Kauffman K. J.; Kaczmarek J. C.; McClellan R. L.; Jhunjhunwala S.; Tibbitt M. W.; Zeng M. D.; Appel E. A.; Dorkin J. R.; Mir F. F.; Yang J. H.; Oberli M. A.; Heartlein M. W.; DeRosa F.; Langer R.; Anderson D. G. Synthesis and Biological Evaluation of Ionizable Lipid Materials for the In Vivo Delivery of Messenger RNA to B Lymphocytes. Adv. Mater. 2017, 29 (33), 1606944 10.1002/adma.201606944. [DOI] [PubMed] [Google Scholar]
  106. Pattipeiluhu R.; Arias-Alpizar G.; Basha G.; Chan K. Y. T.; Bussmann J.; Sharp T. H.; Moradi M. A.; Sommerdijk N.; Harris E. N.; Cullis P. R.; Kros A.; Witzigmann D.; Campbell F. Anionic Lipid Nanoparticles Preferentially Deliver mRNA to the Hepatic Reticuloendothelial System. Adv. Mater. 2022, 34 (16), e2201095 10.1002/adma.202201095. [DOI] [PMC free article] [PubMed] [Google Scholar]
  107. Cheng Q.; Wei T.; Farbiak L.; Johnson L. T.; Dilliard S. A.; Siegwart D. J. Selective organ targeting (SORT) nanoparticles for tissue-specific mRNA delivery and CRISPR–Cas gene editing. Nat. Nanotechnol. 2020, 15 (4), 313–320. 10.1038/s41565-020-0669-6. [DOI] [PMC free article] [PubMed] [Google Scholar]
  108. Wei T.; Cheng Q.; Farbiak L.; Anderson D. G.; Langer R.; Siegwart D. J. Delivery of Tissue-Targeted Scalpels: Opportunities and Challenges for In Vivo CRISPR/Cas-Based Genome Editing. ACS Nano 2020, 14 (8), 9243–9262. 10.1021/acsnano.0c04707. [DOI] [PMC free article] [PubMed] [Google Scholar]
  109. Kowalski P. S.; Capasso Palmiero U.; Huang Y.; Rudra A.; Langer R.; Anderson D. G. Ionizable Amino-Polyesters Synthesized via Ring Opening Polymerization of Tertiary Amino-Alcohols for Tissue Selective mRNA Delivery. Adv. Mater. 2018, 30, e1801151 10.1002/adma.201801151. [DOI] [PMC free article] [PubMed] [Google Scholar]
  110. Fenton O. S.; Kauffman K. J.; McClellan R. L.; Appel E. A.; Dorkin J. R.; Tibbitt M. W.; Heartlein M. W.; DeRosa F.; Langer R.; Anderson D. G. Bioinspired Alkenyl Amino Alcohol Ionizable Lipid Materials for Highly Potent In Vivo mRNA Delivery. Adv. Mater. 2016, 28 (15), 2939–43. 10.1002/adma.201505822. [DOI] [PMC free article] [PubMed] [Google Scholar]
  111. Fenton O. S.; Kauffman K. J.; Kaczmarek J. C.; McClellan R. L.; Jhunjhunwala S.; Tibbitt M. W.; Zeng M. D.; Appel E. A.; Dorkin J. R.; Mir F. F.; Yang J. H.; Oberli M. A.; Heartlein M. W.; DeRosa F.; Langer R.; Anderson D. G. Synthesis and Biological Evaluation of Ionizable Lipid Materials for the In Vivo Delivery of Messenger RNA to B Lymphocytes. Adv. Mater. 2017, 29 (33), 1606944 10.1002/adma.201606944. [DOI] [PubMed] [Google Scholar]
  112. Fenton O. S.; Kauffman K. J.; McClellan R. L.; Kaczmarek J. C.; Zeng M. D.; Andresen J. L.; Rhym L. H.; Heartlein M. W.; DeRosa F.; Anderson D. G. Customizable Lipid Nanoparticle Materials for the Delivery of siRNAs and mRNAs. Angew. Chem. Int. Ed Engl. 2018, 57 (41), 13582–13586. 10.1002/anie.201809056. [DOI] [PMC free article] [PubMed] [Google Scholar]
  113. Gomi M.; Sakurai Y.; Sato M.; Tanaka H.; Miyatake Y.; Fujiwara K.; Watanabe M.; Shuto S.; Nakai Y.; Tange K.; Hatakeyama H.; Akita H. Delivering mRNA to Secondary Lymphoid Tissues by Phosphatidylserine-Loaded Lipid Nanoparticles. Adv. Healthc Mater. 2023, 12 (9), e2202528 10.1002/adhm.202202528. [DOI] [PubMed] [Google Scholar]
  114. Li B.; Luo X.; Deng B.; Giancola J. B.; McComb D. W.; Schmittgen T. D.; Dong Y. Effects of local structural transformation of lipid-like compounds on delivery of messenger RNA. Sci. Rep. 2016, 6, 22137. 10.1038/srep22137. [DOI] [PMC free article] [PubMed] [Google Scholar]
  115. Ni H.; Hatit M. Z. C.; Zhao K.; Loughrey D.; Lokugamage M. P.; Peck H. E.; Cid A. D.; Muralidharan A.; Kim Y.; Santangelo P. J.; Dahlman J. E. Piperazine-derived lipid nanoparticles deliver mRNA to immune cells in vivo. Nat. Commun. 2022, 13 (1), 4766. 10.1038/s41467-022-32281-5. [DOI] [PMC free article] [PubMed] [Google Scholar]
  116. Veiga N.; Goldsmith M.; Granot Y.; Rosenblum D.; Dammes N.; Kedmi R.; Ramishetti S.; Peer D. Cell specific delivery of modified mRNA expressing therapeutic proteins to leukocytes. Nat. Commun. 2018, 9 (1), 4493. 10.1038/s41467-018-06936-1. [DOI] [PMC free article] [PubMed] [Google Scholar]
  117. Tombácz I.; Laczkó D.; Shahnawaz H.; Muramatsu H.; Natesan A.; Yadegari A.; Papp T. E.; Alameh M. G.; Shuvaev V.; Mui B. L.; Tam Y. K.; Muzykantov V.; Pardi N.; Weissman D.; Parhiz H. Highly efficient CD4+ T-cell targeting and genetic recombination using engineered CD4+ cell-homing mRNA-LNPs. Mol. Ther. 2021, 29 (11), 3293–3304. 10.1016/j.ymthe.2021.06.004. [DOI] [PMC free article] [PubMed] [Google Scholar]
  118. Rurik J. G.; Tombácz I.; Yadegari A.; Méndez Fernández P. O.; Shewale S. V.; Li L.; Kimura T.; Soliman O. Y.; Papp T. E.; Tam Y. K.; Mui B. L.; Albelda S. M.; Puré E.; June C. H.; Aghajanian H.; Weissman D.; Parhiz H.; Epstein J. A. CAR T cells produced in vivo to treat cardiac injury. Science. 2022, 375 (6576), 91–96. 10.1126/science.abm0594. [DOI] [PMC free article] [PubMed] [Google Scholar]
  119. Katakowski J. A.; Mukherjee G.; Wilner S. E.; Maier K. E.; Harrison M. T.; DiLorenzo T. P.; Levy M.; Palliser D. Delivery of siRNAs to Dendritic Cells Using DEC205-Targeted Lipid Nanoparticles to Inhibit Immune Responses. Mol. Ther. 2016, 24 (1), 146–55. 10.1038/mt.2015.175. [DOI] [PMC free article] [PubMed] [Google Scholar]
  120. Sago C. D.; Lokugamage M. P.; Loughrey D.; Lindsay K. E.; Hincapie R.; Krupczak B. R.; Kalathoor S.; Sato M.; Echeverri E. S.; Fitzgerald J. P.; Gan Z.; Gamboa L.; Paunovska K.; Sanhueza C. A.; Hatit M. Z. C.; Finn M. G.; Santangelo P. J.; Dahlman J. E. Augmented lipid-nanoparticle-mediated in vivo genome editing in the lungs and spleen by disrupting Cas9 activity in the liver. Nat. Biomed Eng. 2022, 6 (2), 157–167. 10.1038/s41551-022-00847-9. [DOI] [PubMed] [Google Scholar]
  121. Kubiatowicz L. J.; Mohapatra A.; Krishnan N.; Fang R. H.; Zhang L. mRNA nanomedicine: Design and recent applications. Exploration (Beijing) 2022, 2 (6), 20210217 10.1002/EXP.20210217. [DOI] [PMC free article] [PubMed] [Google Scholar]
  122. Lokugamage M. P.; Vanover D.; Beyersdorf J.; Hatit M. Z. C.; Rotolo L.; Echeverri E. S.; Peck H. E.; Ni H.; Yoon J. K.; Kim Y.; Santangelo P. J.; Dahlman J. E. Optimization of lipid nanoparticles for the delivery of nebulized therapeutic mRNA to the lungs. Nat. Biomed Eng. 2021, 5 (9), 1059–1068. 10.1038/s41551-021-00786-x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  123. Teng Z.; Meng L. Y.; Yang J. K.; He Z.; Chen X. G.; Liu Y. Bridging nanoplatform and vaccine delivery, a landscape of strategy to enhance nasal immunity. J. Controlled Release 2022, 351, 456–475. 10.1016/j.jconrel.2022.09.044. [DOI] [PubMed] [Google Scholar]
  124. Fehervari Z. Intranasal vaccination. Nat. Immunol. 2021, 22 (9), 1071. 10.1038/s41590-021-01016-x. [DOI] [PubMed] [Google Scholar]
  125. Nicolai L.; Leunig A.; Pekayvaz K.; Esefeld M.; Anjum A.; Rath J.; Riedlinger E.; Ehreiser V.; Mader M.; Eivers L.; Hoffknecht M. L.; Zhang Z.; Kugelmann D.; Rossaro D.; Escaig R.; Kaiser R.; Polewka V.; Titova A.; Petzold T.; Spiekermann K.; Iannacone M.; Thiele T.; Greinacher A.; Stark K.; Massberg S. Thrombocytopenia and splenic platelet-directed immune responses after IV ChAdOx1 nCov-19 administration. Blood. 2022, 140 (5), 478–490. 10.1182/blood.2021014712. [DOI] [PMC free article] [PubMed] [Google Scholar]
  126. Griffiths G.; Gruenberg J.; Marsh M.; Wohlmann J.; Jones A. T.; Parton R. G. Nanoparticle entry into cells; the cell biology weak link. Adv. Drug Deliv Rev. 2022, 188, 114403 10.1016/j.addr.2022.114403. [DOI] [PubMed] [Google Scholar]
  127. Woodman P. G.; Futter C. E. Multivesicular bodies: co-ordinated progression to maturity. Curr. Opin Cell Biol. 2008, 20 (4), 408–14. 10.1016/j.ceb.2008.04.001. [DOI] [PMC free article] [PubMed] [Google Scholar]
  128. Wittrup A.; Ai A.; Liu X.; Hamar P.; Trifonova R.; Charisse K.; Manoharan M.; Kirchhausen T.; Lieberman J. Visualizing lipid-formulated siRNA release from endosomes and target gene knockdown. Nat. Biotechnol. 2015, 33 (8), 870–6. 10.1038/nbt.3298. [DOI] [PMC free article] [PubMed] [Google Scholar]
  129. Gilleron J.; Querbes W.; Zeigerer A.; Borodovsky A.; Marsico G.; Schubert U.; Manygoats K.; Seifert S.; Andree C.; Stöter M.; Epstein-Barash H.; Zhang L.; Koteliansky V.; Fitzgerald K.; Fava E.; Bickle M.; Kalaidzidis Y.; Akinc A.; Maier M.; Zerial M. Image-based analysis of lipid nanoparticle-mediated siRNA delivery, intracellular trafficking and endosomal escape. Nat. Biotechnol. 2013, 31 (7), 638–46. 10.1038/nbt.2612. [DOI] [PubMed] [Google Scholar]
  130. Yoo Y. J.; Lee C. H.; Park S. H.; Lim Y. T. Nanoparticle-based delivery strategies of multifaceted immunomodulatory RNA for cancer immunotherapy. J. Controlled Release 2022, 343, 564–583. 10.1016/j.jconrel.2022.01.047. [DOI] [PubMed] [Google Scholar]
  131. Spadea A.; Jackman M.; Cui L.; Pereira S.; Lawrence M. J.; Campbell R. A.; Ashford M. Nucleic Acid-Loaded Lipid Nanoparticle Interactions with Model Endosomal Membranes. ACS Appl. Mater. Interfaces 2022, 14 (26), 30371–30384. 10.1021/acsami.2c06065. [DOI] [PMC free article] [PubMed] [Google Scholar]
  132. Degors I. M. S.; Wang C.; Rehman Z. U.; Zuhorn I. S. Carriers Break Barriers in Drug Delivery: Endocytosis and Endosomal Escape of Gene Delivery Vectors. Acc. Chem. Res. 2019, 52 (7), 1750–1760. 10.1021/acs.accounts.9b00177. [DOI] [PMC free article] [PubMed] [Google Scholar]
  133. Zhang Y.; Sun C.; Wang C.; Jankovic K. E.; Dong Y. Lipids and Lipid Derivatives for RNA Delivery. Chem. Rev. 2021, 121 (20), 12181–12277. 10.1021/acs.chemrev.1c00244. [DOI] [PMC free article] [PubMed] [Google Scholar]
  134. Halali M. A.; Larocque M.; de Lannoy C.-F.ço. Investigating the stability of electrically conductive membranes. J. Membr. Sci. 2021, 627, 119181 10.1016/j.memsci.2021.119181. [DOI] [Google Scholar]
  135. Nakamura T.; Nakade T.; Yamada K.; Sato Y.; Harashima H. The hydrophobic tail of a pH-sensitive cationic lipid influences siRNA transfection activity and toxicity in human NK cell lines. Int. J. Pharm. 2021, 609, 121140 10.1016/j.ijpharm.2021.121140. [DOI] [PubMed] [Google Scholar]
  136. Tanaka H.; Takata N.; Sakurai Y.; Yoshida T.; Inoue T.; Tamagawa S.; Nakai Y.; Tange K.; Yoshioka H.; Maeki M.; Tokeshi M.; Akita H. Delivery of Oligonucleotides Using a Self-Degradable Lipid-Like Material. Pharmaceutics. 2021, 13 (4), 544. 10.3390/pharmaceutics13040544. [DOI] [PMC free article] [PubMed] [Google Scholar]
  137. Lam K.; Leung A.; Martin A.; Wood M.; Schreiner P.; Palmer L.; Daly O.; Zhao W.; McClintock K.; Heyes J. Unsaturated, Trialkyl Ionizable Lipids are Versatile Lipid-Nanoparticle Components for Therapeutic and Vaccine Applications. Adv. Mater. 2023, 35 (15), e2209624 10.1002/adma.202209624. [DOI] [PubMed] [Google Scholar]
  138. Hald Albertsen C.; Kulkarni J. A.; Witzigmann D.; Lind M.; Petersson K.; Simonsen J. B. The role of lipid components in lipid nanoparticles for vaccines and gene therapy. Adv. Drug Deliv Rev. 2022, 188, 114416 10.1016/j.addr.2022.114416. [DOI] [PMC free article] [PubMed] [Google Scholar]
  139. Beg S.; Almalki W. H.; Khatoon F.; Alharbi K. S.; Alghamdi S.; Akhter M. H.; Khalilullah H.; Baothman A. A.; Hafeez A.; Rahman M.; Akhter S.; Choudhry H. Lipid/polymer-based nanocomplexes in nucleic acid delivery as cancer vaccines. Drug Discov Today 2021, 26 (8), 1891–1903. 10.1016/j.drudis.2021.02.013. [DOI] [PubMed] [Google Scholar]
  140. Patel S.; Ashwanikumar N.; Robinson E.; Xia Y.; Mihai C.; Griffith J. P. 3rd; Hou S.; Esposito A. A.; Ketova T.; Welsher K.; Joyal J. L.; Almarsson Ö; Sahay G. Naturally occurring cholesterol analogs in lipid nanoparticles induce polymorphic shape and enhance intracellular delivery of mRNA. Nat. Commun. 2020, 11 (1), 983. 10.1038/s41467-020-14527-2. [DOI] [PMC free article] [PubMed] [Google Scholar]; Erratum. Nat. Commun. 2020, 11, 13435. 10.1038/s41467-020-14527-232632117
  141. Kim J.; Jozic A.; Lin Y.; Eygeris Y.; Bloom E.; Tan X.; Acosta C.; MacDonald K. D.; Welsher K. D.; Sahay G. Engineering Lipid Nanoparticles for Enhanced Intracellular Delivery of mRNA through Inhalation. ACS Nano 2022, 16 (9), 14792–14806. 10.1021/acsnano.2c05647. [DOI] [PMC free article] [PubMed] [Google Scholar]
  142. Álvarez-Benedicto E.; Farbiak L.; Márquez Ramírez M.; Wang X.; Johnson L. T.; Mian O.; Guerrero E. D.; Siegwart D. J. Optimization of phospholipid chemistry for improved lipid nanoparticle (LNP) delivery of messenger RNA (mRNA). Biomater Sci. 2022, 10 (2), 549–559. 10.1039/D1BM01454D. [DOI] [PMC free article] [PubMed] [Google Scholar]
  143. Sato Y.; Matsui H.; Sato R.; Harashima H. Neutralization of negative charges of siRNA results in improved safety and efficient gene silencing activity of lipid nanoparticles loaded with high levels of siRNA. J. Controlled Release 2018, 284, 179–187. 10.1016/j.jconrel.2018.06.017. [DOI] [PubMed] [Google Scholar]
  144. Elber R. Defect Formation and Peptide Permeation across Phospholipid Membranes. J. Phys. Chem. B 2023, 127 (37), 7810–7818. 10.1021/acs.jpcb.3c04895. [DOI] [PubMed] [Google Scholar]
  145. Kim I. G.; Jung W. H.; You G.; Lee H.; Shin Y. J.; Lim S. W.; Chung B. H.; Mok H. Efficient Delivery of Globotriaosylceramide Synthase siRNA using Polyhistidine-Incorporated Lipid Nanoparticles. Macromol. Biosci. 2023, 23 (4), e2200423 10.1002/mabi.202200423. [DOI] [PubMed] [Google Scholar]
  146. Pardi N.; Tuyishime S.; Muramatsu H.; Kariko K.; Mui B. L.; Tam Y. K.; Madden T. D.; Hope M. J.; Weissman D. Expression kinetics of nucleoside-modified mRNA delivered in lipid nanoparticles to mice by various routes. J. Controlled Release 2015, 217, 345–51. 10.1016/j.jconrel.2015.08.007. [DOI] [PMC free article] [PubMed] [Google Scholar]
  147. Committee for Medicinal Products for Human Use (CHMP). EMA Assessment report Comirnaty Common name: COVID-19 mRNA vaccine (nucleoside-modified), 2020. https://www.ema.europa.eu/en/documents/assessment-report/comirnaty-epar-public-assessment-report_en.pdf (accessed Oct. 7, 2023).
  148. EMA COVID-19 Vaccine Moderna: Summary of Product Characteristics, 2021. https://www.ema.europa.eu/en/documents/product-information/covid-19-vaccine-moderna-epar-product-information_en.pdf (accessed Oct. 7, 2023).
  149. EMA Onpattro: Summary of Product Characteristics, 2018. https://www.ema.europa.eu/en/documents/product-information/onpattro-epar-product-information_en.pdf (accessed Oct. 7, 2023).
  150. Hansen L.; Van Renterghem J.; Daoussi R.; Vervaet C.; Remon J. P.; De Beer T. Spectroscopic evaluation of a freeze-dried vaccine during an accelerated stability study. Eur J Pharm Biopharm. 2016, 104, 89–100. 10.1016/j.ejpb.2016.04.010. [DOI] [PubMed] [Google Scholar]
  151. Muramatsu H.; Lam K.; Bajusz C.; Laczkó D.; Karikó K.; Schreiner P.; Martin A.; Lutwyche P.; Heyes J.; Pardi N. Lyophilization provides long-term stability for a lipid nanoparticle-formulated, nucleoside-modified mRNA vaccine. Mol. Ther. 2022, 30 (5), 1941–1951. 10.1016/j.ymthe.2022.02.001. [DOI] [PMC free article] [PubMed] [Google Scholar]
  152. Allergic Reactions Including Anaphylaxis After Receipt of the First Dose of Pfizer-BioNTech COVID-19 Vaccine – United States, December 14–23, 2020. MMWR Morb Mortal Wkly Rep. 2021, 70 (2), 46–51. 10.15585/mmwr.mm7002e1. [DOI] [PMC free article] [PubMed] [Google Scholar]
  153. Allergic Reactions Including Anaphylaxis After Receipt of the First Dose of Moderna COVID-19 Vaccine – United States, December 21, 2020-January 10, 2021. MMWR Morb Mortal Wkly Rep. 2021, 70 (4), 125–129. 10.15585/mmwr.mm7004e1. [DOI] [PMC free article] [PubMed] [Google Scholar]
  154. Ganson N. J.; Povsic T. J.; Sullenger B. A.; Alexander J. H.; Zelenkofske S. L.; Sailstad J. M.; Rusconi C. P.; Hershfield M. S. Preexisting anti-polyethylene glycol antibody linked to first-exposure allergic reactions to pegnivacogin, a PEGylated RNA aptamer. J. Allergy Clin Immunol. 2016, 137 (5), 1610–1613.e7. 10.1016/j.jaci.2015.10.034. [DOI] [PMC free article] [PubMed] [Google Scholar]
  155. Zhou Z. H.; Stone C. A. Jr; Jakubovic B.; Phillips E. J.; Sussman G.; Park J.; Hoang U.; Kirshner S. L.; Levin R.; Kozlowski S. Anti-PEG IgE in anaphylaxis associated with polyethylene glycol. J. Allergy Clin Immunol Pract. 2021, 9 (4), 1731–1733.e3. 10.1016/j.jaip.2020.11.011. [DOI] [PMC free article] [PubMed] [Google Scholar]
  156. Huang P.; Deng H.; Zhou Y.; Chen X. The roles of polymers in mRNA delivery. Matter 2022, 5, 1670. 10.1016/j.matt.2022.03.006. [DOI] [Google Scholar]
  157. Guo S.; Fu D.; Utupova A.; Sun D.; Zhou M.; Jin Z.; Zhao K. Applications of polymer-based nanoparticles in vaccine field. Nat. Rev. 2019, 8 (1), 143–155. 10.1515/ntrev-2019-0014. [DOI] [Google Scholar]
  158. Huang P.; Jiang L.; Pan H.; Ding L.; Zhou B.; Zhao M.; Zou J.; Li B.; Qi M.; Deng H.; Zhou Y.; Chen X. An Integrated Polymeric mRNA Vaccine without Inflammation Side Effects for Cellular Immunity Mediated Cancer Therapy. Adv. Mater. 2023, 35 (3), e2207471 10.1002/adma.202207471. [DOI] [PubMed] [Google Scholar]
  159. Huang K. W.; Hsu F. F.; Qiu J. T.; Chern G. J.; Lee Y. A.; Chang C. C.; Huang Y. T.; Sung Y. C.; Chiang C. C.; Huang R. L.; Lin C. C.; Dinh T. K.; Huang H. C.; Shih Y. C.; Alson D.; Lin C. Y.; Lin Y. C.; Chang P. C.; Lin S. Y.; Chen Y. Highly efficient and tumor-selective nanoparticles for dual-targeted immunogene therapy against cancer. Sci. Adv. 2020, 6 (3), eaax5032 10.1126/sciadv.aax5032. [DOI] [PMC free article] [PubMed] [Google Scholar]
  160. Xu C.; Nam J.; Hong H.; Xu Y.; Moon J. J. Positron Emission Tomography-Guided Photodynamic Therapy with Biodegradable Mesoporous Silica Nanoparticles for Personalized Cancer Immunotherapy. ACS Nano 2019, 13 (10), 12148–12161. 10.1021/acsnano.9b06691. [DOI] [PMC free article] [PubMed] [Google Scholar]
  161. Zhang W.; Liu Y.; Min Chin J.; Phua K. K. L. Sustained release of PKR inhibitor C16 from mesoporous silica nanoparticles significantly enhances mRNA translation and anti-tumor vaccination. Eur. J. Pharm. Biopharm 2021, 163, 179–187. 10.1016/j.ejpb.2021.03.011. [DOI] [PubMed] [Google Scholar]
  162. Lou B.; De Koker S.; Lau C. Y. J.; Hennink W. E.; Mastrobattista E. mRNA Polyplexes with Post-Conjugated GALA Peptides Efficiently Target, Transfect, and Activate Antigen Presenting Cells. Bioconjug Chem. 2019, 30 (2), 461–475. 10.1021/acs.bioconjchem.8b00524. [DOI] [PMC free article] [PubMed] [Google Scholar]
  163. Li Y.; Ma X.; Yue Y.; Zhang K.; Cheng K.; Feng Q.; Ma N.; Liang J.; Zhang T.; Zhang L.; Chen Z.; Wang X.; Ren L.; Zhao X.; Nie G. Rapid Surface Display of mRNA Antigens by Bacteria-Derived Outer Membrane Vesicles for a Personalized Tumor Vaccine. Adv. Mater. 2022, 34 (20), e2109984 10.1002/adma.202109984. [DOI] [PubMed] [Google Scholar]
  164. Valadi H.; Ekström K.; Bossios A.; Sjöstrand M.; Lee J. J.; Lötvall J. O. Exosome-mediated transfer of mRNAs and microRNAs is a novel mechanism of genetic exchange between cells. Nat. Cell Biol. 2007, 9 (6), 654–659. 10.1038/ncb1596. [DOI] [PubMed] [Google Scholar]
  165. Koh E.; Lee E. J.; Nam G. H.; Hong Y.; Cho E.; Yang Y.; Kim I. S. Exosome-SIRPα, a CD47 blockade increases cancer cell phagocytosis. Biomaterials. 2017, 121, 121–129. 10.1016/j.biomaterials.2017.01.004. [DOI] [PubMed] [Google Scholar]
  166. Kong N.; Tao W.; Ling X.; Wang J.; Xiao Y.; Shi S.; Ji X.; Shajii A.; Gan S. T.; Kim N. Y.; Duda D. G.; Xie T.; Farokhzad O. C.; Shi J. Synthetic mRNA nanoparticle-mediated restoration of p53 tumor suppressor sensitizes p53-deficient cancers to mTOR inhibition. Sci. Transl Med. 2019, 11 (523), eaaw1565 10.1126/scitranslmed.aaw1565. [DOI] [PMC free article] [PubMed] [Google Scholar]
  167. Duan L.; Xu L.; Xu X.; Qin Z.; Zhou X.; Xiao Y.; Liang Y.; Xia J. Exosome-mediated delivery of gene vectors for gene therapy. Nanoscale 2021, 13 (3), 1387–1397. 10.1039/D0NR07622H. [DOI] [PubMed] [Google Scholar]
  168. Zhang Y.; Liu Q.; Zhang X.; Huang H.; Tang S.; Chai Y.; Xu Z.; Li M.; Chen X.; Liu J.; Yang C. Recent advances in exosome-mediated nucleic acid delivery for cancer therapy. J. Nanobiotechnology 2022, 20 (1), 279. 10.1186/s12951-022-01472-z. [DOI] [PMC free article] [PubMed] [Google Scholar]
  169. Ma Y.; Sun L.; Zhang J.; Chiang C. L.; Pan J.; Wang X.; Kwak K. J.; Li H.; Zhao R.; Rima X. Y.; Zhang C.; Zhang A.; Liu Y.; He Z.; Hansford D.; Reategui E.; Liu C.; Lee A. S.; Yuan Y.; Lee L. J. Exosomal mRNAs for Angiogenic-Osteogenic Coupled Bone Repair. Adv. Sci. (Weinh) 2023, 10 (33), e2302622 10.1002/advs.202302622. [DOI] [PMC free article] [PubMed] [Google Scholar]
  170. You Y.; Tian Y.; Yang Z.; Shi J.; Kwak K. J.; Tong Y.; Estania A. P.; Cao J.; Hsu W. H.; Liu Y.; Chiang C. L.; Schrank B. R.; Huntoon K.; Lee D.; Li Z.; Zhao Y.; Zhang H.; Gallup T. D.; Ha J.; Dong S.; Li X.; Wang Y.; Lu W. J.; Bahrani E.; Lee L. J.; Teng L.; Jiang W.; Lan F.; Kim B. Y. S.; Lee A. S. Intradermally delivered mRNA-encapsulating extracellular vesicles for collagen-replacement therapy. Nat. Biomed Eng. 2023, 7 (7), 887–900. 10.1038/s41551-022-00989-w. [DOI] [PubMed] [Google Scholar]
  171. Kim J.; Afshari A.; Sengupta R.; Sebastiano V.; Gupta A.; Kim Y. H; Iorns E.; Tsui R.; Denis A.; Perfito N.; Errington T. M; Iorns E.; Tsui R.; Denis A.; Perfito N.; Errington T. M Replication study: Melanoma exosomes educate bone marrow progenitor cells toward a pro-metastatic phenotype through MET. Elife 2018, 7, e39944 10.7554/eLife.39944. [DOI] [PMC free article] [PubMed] [Google Scholar]
  172. Lai C. P.; Mardini O.; Ericsson M.; Prabhakar S.; Maguire C.; Chen J. W.; Tannous B. A.; Breakefield X. O. Dynamic biodistribution of extracellular vesicles in vivo using a multimodal imaging reporter. ACS Nano 2014, 8 (1), 483–494. 10.1021/nn404945r. [DOI] [PMC free article] [PubMed] [Google Scholar]
  173. Supe S.; Upadhya A.; Tripathi S.; Dighe V.; Singh K. Liposome-polyethylenimine complexes for the effective delivery of HuR siRNA in the treatment of diabetic retinopathy. Drug Deliv Transl Res. 2023, 13 (6), 1675–1698. 10.1007/s13346-022-01281-9. [DOI] [PubMed] [Google Scholar]
  174. Persano S.; Guevara M. L.; Li Z.; Mai J.; Ferrari M.; Pompa P. P.; Shen H. Lipopolyplex potentiates anti-tumor immunity of mRNA-based vaccination. Biomaterials. 2017, 125, 81–89. 10.1016/j.biomaterials.2017.02.019. [DOI] [PMC free article] [PubMed] [Google Scholar]
  175. Fang R. H.; Gao W.; Zhang L. Targeting drugs to tumors using cell membrane-coated nanoparticles. Nat. Rev. Clin Oncol. 2023, 20 (1), 33–48. 10.1038/s41571-022-00699-x. [DOI] [PubMed] [Google Scholar]
  176. Wu S.; Yun J.; Tang W.; Familiari G.; Relucenti M.; Wu J.; Li X.; Chen H.; Chen R. Therapeutic m6A Eraser ALKBH5 mRNA-Loaded Exosome-Liposome Hybrid Nanoparticles Inhibit Progression of Colorectal Cancer in Preclinical Tumor Models. ACS Nano 2023, 17 (12), 11838–11854. 10.1021/acsnano.3c03050. [DOI] [PubMed] [Google Scholar]

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