Skip to main content
NCBI home page
Journal of Diabetes and Metabolic Disorders logoLink to Journal of Diabetes and Metabolic Disorders
. 2020 Aug 12;19(2):1037–1044. doi: 10.1007/s40200-020-00602-4

The modulation of mature dendritic cells from patients with type 1 diabetes using human periodontal ligament stem cells. An in-vitro study

L Ashour 1, R A Al Habashneh 1, M M Al-Mrahelh 2, D Abuarqoub 2,3, Y S Khader 4, H Jafar 2,5, Abdalla S Awidi 2,5,✉
PMCID: PMC7843723  PMID: 33520821

Abstract

Objective

This in vitro study aimed to investigate whether human periodontal ligament stem cells isolated from impacted third molars can modify the maturation and phenotype of monocyte-derived dendritic cells pulsed with GAD-65 obtained from patients with type 1 diabetes.

Background

Human periodontal ligament stem cells (PDLSCs) have been found to display cell surface marker characteristics similar to bone marrow stromal stem cells (BMSSCs). The immunosuppressive effects on dendritic cells (DCs), T and B cells as well as their low immunogenicity allow the use of PDLSCs in stem cell therapies for autoimmune diseases including type 1 diabetes (T1D). Studies on the immunomodulatory potential of PDLSCs in the context type 1 diabetes are lacking but are therefore worth pursuing.

Methods

CD14 + monocytes isolated from peripheral blood mononuclear cells (PBMNCs) of type 1 diabetic patients were differentiated into immature Dendritic Cells (iDCs) and then maturation was induced to generate Mature Dendritic Cells (mDCs). The mDCs were pulsed with human recombinant GAD-65 and then co-cultured with PDLSCs that were isolated from impacted third molars and characterized. The changes in the levels of differentiation and maturation surface markers on the dendritic cells were analyzed by flow cytometry at the immature state, mature state and after the co-culture experiment. The levels of the secreted cytokines; IL-6, IL-10, and TGF-β were measured by ELISA in cell-free culture supernatant.

Results

PDLSCs exerted an immunosuppressive effect on fully mature dendritic cells from patients with type 1 diabetes. This immunoregulatory property of was apparent by the reduction of all maturation markers including CD80, CD83, CD86, CD40, CD1a, CD209 and HLA-DR. Moreover, there was a detection of high levels of anti-inflammatory cytokines in the co-culture supernatant media including a significant increase in the concentration of IL-6 and TGF-β.

Conclusions

The current in vitro study provides strong evidence that PDLSCs seem to be a very promising source for overcoming the autoimmune destruction seen in T1D as they exerted an immunosuppressive effect on monocyte derived mDCs from patients with T1D. Additional studies should be conducted to further reveal the immunomodulatory and suppressive properties of PDLSCs and their potential use in immunotherapy for this disease.

Keywords: Diabetes, Inflammation, Stem Cells, Periodontal Ligament Stem Cells, Type 1 Diabetes, Cell Therapy, Immunotherapy, Cytokines

Introduction

Type 1 diabetes (T1D) is an autoimmune disease characterized by the destruction of insulin-producing β cells in the islets of Langerhans of the pancreas. It accounts for about 5–10% of all patients with diabetes and the worldwide incidence is increasing by almost 3% every year [1]. Dendritic Cells (DCs) seems to play a pivotal role at all stages of the autoimmune response seen in T1D, moreover they are also used as immunotherapeutic agents for the disease since they play an important role in maintaining self-tolerance and in activating naïve T cells [2]. The nature of the elicited T-cell response is determined by specific cytokines secreted by DCs [3].

Mature, immunologically competent DCs are considered the most efficient antigen-presenting cells (APCs) [4, 5]. In T1D, DCs present within the pancreas begin by taking up released β-cell-derived antigens mainly GAD-65; Glutamic Acid Decarboxylase 65, where they then migrate to the draining lymph nodes where they activate naïve islet-specific CD4 + and CD8 + T-cells. These activated islet-specific T cells will then migrate back to the pancreas where they will infiltrate and collect around the islets. At some point, the infiltrate becomes invasive and destruction of the pancreatic β cells begins eventually leading to a loss in the balance between the regulatory and inflammatory T cell populations [6].

Mesenchymal stem cells (MSCs) isolated from several adult tissues have emerged as a promising treatment modality for different autoimmune diseases, consequently receiving great attention for the treatment and overcoming the autoimmunity seen in T1D [7]. This is mainly due to their ability to directly contribute to islet regeneration by differentiating into various lineages, including endodermal lines, generating insulin-producing cells [8, 9], and more importantly due to their particular immunosuppressive capacities [10]. It has been demonstrated both in vitro and in vivo that MSCs were capable of inhibiting DC differentiation, maturation and function as well as inducting regulatory DCs that can in turn induce regulatory T cells, this certainly accounts for their multilevel immunomodulatory properties [11, 12]. This immunoregulatory property is in fact thought to be the main mechanism by which they exert their antidiabetic effects [13].

Previous studies demonstrated that MSCs were capable of inhibiting an inflammatory response in patients with T1D to an islet antigen glutamic acid decarboxylase stimulus [14]. This involved PGE2 and TGF-β signaling pathways as well as secretion of the anti-inflammatory cytokine, IL-10, suggesting a switch to an anti-inflammatory state [14]. In addition to that, it was demonstrated that MSCs-conditioned DCs isolated from T1D patients showed an increased secretion IL-10 and IL-6 with a switch to an immature phenotype and reduced levels of activation surface markers [14]. These MSCs-conditioned DCs can result in an inhibition of inflammatory T cell responses and the promotion of a more balanced, regulatory state. [15]. This renders MSC therapy as a promising and suitable therapeutic approach in the sense of controlling the autoimmune pancreas inflammation in T1D and ceasing the disease progression as seen in recent clinical trials [16, 17].

Ever since mesenchymal stem cells were identified from dental tissues, they became one of the most widely researched areas in dentistry and storing them for future clinical applications is being explored. This is due to the fact that these cells are to some extent easy, convenient, and affordable to collect in a non-invasive manner, hence holding promise for a range of therapeutic applications both in regenerative medicine and dentistry [18]. Human periodontal ligament stem cells (PDLSCs) have been found to display cell surface marker characteristics similar to that seen in bone marrow stromal stem cells (BMSSCs) [19, 20]. PDLSCs possesses low immunogenicity, inhibits proliferation of T cells, negatively regulate DC-mediated T-cell immune responses and suppresses B cells proliferation, differentiation, and migration [20, 21]. The low immunogenicity and immunosuppressive effects on DCs, B cells and T cells allow the use of PDLSCs in stem cell therapies specifically in immunotherapy for autoimmune diseases. In the current study, the effects of PDLSCs in the context of T1D were explored for the first time.

To the best of our knowledge, no previous published studies have been conducted to study the immunomodulatory effect of PDLSCs on fully mature DCs from T1D patients. In the present in vitro study, we aimed to test whether PDLSCs can alter the maturation and phenotype of monocyte-derived mDCs pulsed with GAD-65 obtained from patients with type 1 diabetes at the disease onset.

Materials and methods

Sample

A total of five patients with type 1 diabetes (4 males and 1 female) who were diagnosed with early disease onset and positive IFN-γ response to glutamic acid decarboxylase (GAD65) were included in this study. The study approval was obtained from the Institutional Review Board (IRB) at Jordan University of Science and Technology (IRB # 20,180,391). All patients signed an informed consent and were informed about the study purpose and procedures. Blood samples were collected from patients in Sodium Heparin VACUETTE® tubes (Greiner Bio-One International).

Generation of mDCs from monocytes

For the generation of mDCs from monocytes, CD14 + Monocytes were first isolated from peripheral blood mononuclear cells (PBMNCs) of full heparinized blood. The derived CD14 + monocytes were isolated according to the plastic adherence method protocol adopted from the study of Obermaier et al. [22]. The complete medium used for the culture of PBMNCs was supplemented with 10% Platelet Lysate.

The CD14 + monocytes were induced to differentiate into immature DC (iDCs) by incubation in an RPMI 1640 medium (Euroclone S.P.A., Italy) supplemented with 10% Platelet Lysate, 1000 IU/ml GM-CSF and 500 IU/ml IL-4 (both from R&D Systems, USA) for 5 full days. At day 6, the derived iDCs were then matured into mDCs by further addition of 500 IU IL-1β and 500 IU TNF-α (both from R&D Systems, USA) and pulsing them with recombinant human GAD-65 (ABCAM, UK) at a concentration of 10 µg/1 × 106 cells/ml for 2 days.

The level of maturity of iDCs and mDCs was analyzed by flow cytometry at day 6 and 8 of the sample collection, respectively, for the expression of CD14 (PE-CY7), CD80 (APC-H7), CD40 (BV51), CD83 (FITC), CD86 (BV421), CD1a (PE), CD209 (APC) and HLA-DR (Percp-CY5.5) surface markers using conjugated monoclonal antibodies (all from BD, USA). All samples were analyzed using BD FACS Canto II flow cytometer using BD FACS Diva 8 software (BD, USA). The iDCs and mDCs were also observed under an inverted phase-contrast microscope (Axiovert, Zeiss, Germany) at 40X.

Isolation of PDLSCs

PDLSCs were obtained from the National Cell Therapy Center at the University of Jordan. PDLSCs were isolated from impacted third molars of three different healthy patients within 24 h of extraction using the enzymatic method [23]. PDLSCs were characterized according to their differentiation potential and their expression profile of MSC surface markers [24]. The three samples of PDLSCs were sub-cultured and used at passages 3–5 for the co-culture experiments.

Co-culture of PDLSCs with mDCs

For the co-culture experiment, GAD-65 pulsed mDCs from each donor were co-cultured with the three different PDLSCs samples at a ratio of 1:1 and incubated for 2 days. After 2 days of co-culturing (day 10 of the experiment), PDLSCs conditioned DCs were gently aspirated and analyzed by flow cytometry for their expression of CD14, CD80, CD40, CD83, CD86, CD1a, CD209, and HLA-DR surface markers. The cells were observed under an inverted phase-contrast microscope at 40X. Figure 1 shows the flow chart of the work plan.

Fig. 1.

Fig. 1

Open in a new tab

Flow chart of the work plan

Cytokine detection by ELISA

The concentrations of IL-6, IL-10 and TGF-β were measured in cell-free culture supernatant using ELISA. Cell-free culture media were collected from mDCs and PDLSCs at day 8 of the experiment (before the co-culture) and from the PDLSCs conditioned DCs at day 10 (after the co-culture). The concentration of IL-6, IL-10 and TGF-β from the collected samples was measured using IL-6 high sensitivity Human ELISA Kit, IL-10 Human ELISA Kit, and TGF-beta 1 Human ELISA Kit (all kits from ABCAM, UK), respectively. Samples were prepared according to the manufacturer instructions. The absorbance was read on a microplate reader Glumax (Promega, USA) at 450 nm.

Data Analysis

The percentages of surface markers expression and concentration of cytokines were analyzed using IBM SPSS version 22 (IBM Corp. IBM SPSS Statistics for Windows, Version 22.0. Armonk, NY: IBM Corp.) and Graphpad Prism version 8.1.2. Mann-Whitney test was used to compare the mean of the percentages between test and control groups. Differences in the concentration of the cytokines between the samples were analyzed using One-Way ANOVA and post-hoc multiple comparisons. A p-value of less than 0.05 was considered statistically significant.

Results

Morphological appearance of iDCs, mDCs, and conditioned DCs

When examined under the microscope, monocytes derived iDCs were free floating, adopted a round shape and showed short cytoplasmic processes (Fig. 2a), upon maturation, the GAD-65 pulsed mDCs showed more pronounced and longer processes (Fig. 2b). After co-culturing the mDCs with PDLSCs for 2 days, the conditioned DCs implemented a more immature morphological appearance where the cells have lost their long dendritic processes (Fig. 2c).

Fig. 2.

Fig. 2

Open in a new tab

Morphological appearance of (a) monocyte-derived iDCs, (b) GAD-65 pulsed mDCs and (c) DCs cultured with PDLSCs, as observed under an inverted phase-contrast microscope (Axiovert, Zeiss, Germany) at 40X

Co-stimulatory surface markers expression on iDCs, mDCs and conditioned DCs

To determine the level of maturity of iDCs, mDCs and conditioned DCs, flow cytometry was performed to measure the expression profile of CD14, CD80, CD83, CD86, CD40, CD1a, CD209, and HLA-DR surface markers at days 6, 8 and 10 of the experiment, respectively.

Interestingly, our results showed that DCs at both states (immature and mature) lacked the expression of the surface marker CD14. Moreover, the expression of the following co-stimulatory markers was increased significantly upon maturation from; CD80 (p = 0.00), CD83 (p = 0.02), CD1a (p = 0.00), HLA-DR (p = 0.00), and CD209 (p = 0.03). On the other hand, after co-culturing the GAD-65 pulsed mDCs with PDLSCs, the expression of all co-stimulatory surface markers was reduced in a significant manner; CD80 (p = 0.03), CD83 (p = 0.03), CD86 (p = 0.00), CD40 (p = 0.04), CD1a (p = 0.00), CD209 (p = 0.04) and HLA-DR (p = 0.05), with an increase in the expression of CD14 through the co-culturing experiment (p = 0.06) (Figs. 3 and 4).

Fig. 3.

Fig. 3

Open in a new tab

Statistical analysis of the expression of maturation surface markers; CD14, CD80, CD83, CD86, CD40, CD1a, CD209 and HLA-DR, expressed by iDCs, mDCs, and conditioned DCs from patients with T1D. Data were presented as the mean ± SD. A significant difference of the expression of maturation markers was observed among different cell types (*p < 0.05)

Fig. 4.

Fig. 4

Open in a new tab

Representative flow cytometry histogram with overlay of the iDCs (dark blue peak), mDCs (grey peak), and PDLSCs conditioned DCs (light blue peak) from T1D patients. Histograms represents the expression of CD14, CD80, CD83, CD86, CD40, CD1a, CD209, and HLA-DR surface markers

Cytokines profile

To determine the impact of co-culturing mDCs with PDLSCs on the inflammatory cytokines; concentration of TGF-β, IL-6, and IL-10 was measured in the supernatant from the media of the PDLSCs, mDCs and PDLSCs conditioned DCs using ELISA. Our data showed that TGF-β was highly secreted in the conditioned DCs media in a significant manner, as the concentration was 10 folds higher when compared to PDLSCs media (p = 0.00) and mDCs (p = 0.00). Both PDLSCs and mDCs showed very low expression of the aforementioned factor (Fig. 5a).

Fig. 5.

Fig. 5

Open in a new tab

Concentrations of cytokines (a)TGF-β, (b) IL-6, and (c) IL-10 measured by ELISA of supernatant cell culture free media from PDLSCs, mDCs and conditioned DCs. (* p < 0.05)

IL-6 was expressed in all samples. Interestingly, the concentration of IL-6 was significantly higher in PDLSCs media (p = 0.01) and conditioned DCs (p = 0.00) media in comparison to mDCs cell culture media. While, no statistical difference was detected between PDLSCs and conditioned DCs media, as both showed the same level of expression (p = 1.00) (Fig. 5b).

On contrary to IL-6, IL-10 was significantly higher in mDCs supernatant media compared to conditioned DCs media (p = 0.01) and PDLSCs media (p = 0.00) (Fig. 5c).

Discussion

The pathogenesis of T1D has been extensively studied were DCs have been implicated in its pathogenesis as well as used as an immunotherapeutic agent for the disease since they have been shown to possess both protective and pathogenic effects. Recently, several clinical trials have been conducted using tolerogenic DC-based therapies for the treatment of T1D [25]. The autoimmune nature of T1D rationalizes the pursuit for a novel immune based therapy in hopes of halting the disease progression or even preventing the initiation of the disease. The challenge lies in obtaining a treatment that has proven clinical efficiency, has a prolonged effect, lack any adverse effects and most importantly, in the absence of chronic immunosuppression. In the current study, the effects of PDLSCs on DCs in the context of T1D were explored for the first time.

The current study shows that PDLSCs have an immunosuppressive effect on DCs from patients with T1D, similar to the suppressive effect seen in BMMSCs [15]. PDLSCs conditioned DCs adapted an immature morphological appearance where the cells have lost their long dendritic processes, skewing towards a more immature phenotype with increased CD14 expression and a reduction in the expression of all the co-stimulatory surface markers. PDLSCs conditioned DCs had a significantly reduced expression of CD80, CD83, CD86, CD40, CD1a, HLA-DR and CD209 as shown by flow cytometry analysis. This immunosuppressive effect of PDLSCs on mDCs from T1D that was seen in this study is similar to that of other types of MSCs such as BM-MSCs where it was demonstrated in a previous study that BM-MSCs conditioned DCs isolated from T1D patients acquired an immature phenotype with reduced levels of activation markers such as CD80, CD83 and CD86 [15].

Mature, immunologically competent DCs are well known to be the most efficient antigen-presenting cells (APCs) [4, 5]. This antigen presentation and the consequent T cell priming by mDCs is known to be greatly influenced by the receptor-ligand interaction so a reduction in the co-stimulatory surface markers is believed to decrease the antigen-driven inflammatory effector T cell activation. For example, ligation of CD40 or MHC class II molecules triggers the production of the pro-inflammatory cytokine IL-12 in DC[26] and promotes an up-regulation of the costimulatory molecules CD80 and CD86 [27] which are both known to stimulate T cell activation[28, 29]. Additionally, down-regulation of CD83 expression on human DC would results in a much less potent induction of an allogeneic T cell proliferation and a reduction of IFN-γ secretion by established T cells[30] So coming all together, the reduction in the maturation surface markers that was caused by PDLSCs in this study is expected to withhold the DCs ability in stimulating T cells proliferation and differentiation into effector cells.

To further verify the immunoregulatory effect caused by PDLSCs on mDCs from T1D patients, the cytokine profile was studied where the concentration of the anti-inflammatory cytokines IL-6 and TGF-β were shown to be significantly increased in the supernatant cell free culture media from the conditioned DCs. IL-10 was present in the supernatant media from all the samples, however it was present at the highest concentration in mDCs supernatant media. The increase in IL-6 in the co-culture thought to induce the differentiation of monocytes to macrophages rather than to DCs[31] and is furthermore associated with an immunosuppressive and anti-inflammatory properties in DCs [32]. Moreover, studies in animal models have shown that IL-6 signaling regulates hepatic control of insulin sensitivity and glucose tolerance by mediating glucose metabolism [33].

Moreover, the presence of TGF-β at high concentrations at the co-culture experiment demonstrates a switch to an anti-inflammatory and regulatory state since TGF-β is known for inhibiting the proliferation and differentiation of self-reactive CD4 + and CD8 + T cells therefore inducing peripheral tolerance [34]. TGF-b is believed to promote anti-inflammatory conditions by inducing the expansion of T-regulatory cells that are essential for immunological tolerance [35]. It is however not clear whether these cytokines were released from the DCs upon maturation or from the PDLSCs.

Overall, there is an overwhelming mass of evidence that points to immature DCs as being tolerogenic and enabling T1D prevention and reversal [36]. This is supported by the fact that tolerogenic DCs with low expression of costimulatory surface markers share an anti-inflammatory cytokine profile. Moreover, in-vitro these cells showed a weak allogeneic T-cell proliferation and stimulatory function, they even showed the capacity to induce and expand Foxp3 + T regs [37]. Restoring this lost balance between T-reg and effector T cells is believed to delay the progression to clinical type 1 diabetes in high-risk individuals similarly to what is seen in a new phase 2 trial using Teplizumab [38].

In summary, MSCs have been extensively studied for their therapeutic potential in the treatment of T1D. this is mainly due to their pancreatic beta cell restorative capabilities as well as to their immunomodulatory properties. For the first time, we reported the immunomodulatory effect of PDLSCs on mDCs in the context of type 1 diabetes. PDLSCs have grown to have great clinical interest since they possess similar characteristics and abilities to other MSCs including BM-MSCs. In vitro, we demonstrated the immunoregulatory property of PDLSCs on GAD-65 pulsed monocyte-derived DCs by the reduction of all maturation markers and the detection of high levels of anti-inflammatory cytokines. Since DCs are widely known to play a crucial role in the induction of the pathological process in the autoimmune T1D, inhibition of the differentiation and maturation of DCs as well as a shift to an anti-inflammatory cytokine profile represents a promising strategy for the possible use of PDLSCs in immunotherapy for T1D in the sense of controlling the autoimmune destruction of the pancreas, ceasing the disease progression and preserving the remaining β-cells.

Additional studies should be conducted to further reveal the immunomodulatory properties of PDLSCs and their potential use in immunotherapy for the disease. A larger scale study with a larger sample size should be conducted to increase the significance level of the findings. Moreover, the extent by which the PDLSCs conditioned DCs activate cytotoxic and regulatory T lymphocytes should be measured in the context of T1D as well as the direct immunomodulatory effect of PDLSCs on T lymphocytes both in vitro and in vivo assay using NOD mice.

Acknowledgements

We thank the staff of the Cell Therapy Center for their assistance in the conduction of this research.

Funding information

This study was partially supported by the University of Science and Technology Research Fund.

Compliance with ethical standards

Conflicts of interest

Authors declare no conflicts of interest.

Footnotes

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

References

  • 1.Maahs DM, West NA, Lawrence JM, Mayer-Davis EJ. Epidemiology of type 1 diabetes. Endocrinol Metab Clin. 2010;39(3):481–97. [DOI] [PMC free article] [PubMed]
  • 2.Calderon B, Unanue ER. Antigen presentation events in autoimmune diabetes. Curr Opin Immunol. 2012;24(1):119–28. doi: 10.1016/j.coi.2011.11.005. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 3.Tisch R, Wang B. Role of plasmacytoid dendritic cells in type 1 diabetes: friend or foe? Diabetes. 2009;58(1):12–3. doi: 10.2337/db08-1341. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 4.Moser M, Murphy KM. Dendritic cell regulation of T H 1-T H 2 development. Nat Immunol. 2000;1(3):199. [DOI] [PubMed]
  • 5.Théry C, Amigorena S. The cell biology of antigen presentation in dendritic cells. Curr Opin Immunol. 2001;13(1):45–51. doi: 10.1016/S0952-7915(00)00180-1. [DOI] [PubMed] [Google Scholar]
  • 6.Morel PA. Dendritic cell subsets in type 1 diabetes: friend or foe? Front Immunol. 2013;4:415. [DOI] [PMC free article] [PubMed]
  • 7.Klinker MW, Wei CH. Mesenchymal stem cells in the treatment of inflammatory and autoimmune diseases in experimental animal models. World J Stem Cells. 2015;7(3):556. doi: 10.4252/wjsc.v7.i3.556. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 8.Xie QP, Huang H, Xu B, Dong X, Gao SL, Zhang B, Wu YL. Human bone marrow mesenchymal stem cells differentiate into insulin-producing cells upon microenvironmental manipulation in vitro. Differentiation. 2009;77(5):483–91. doi: 10.1016/j.diff.2009.01.001. [DOI] [PubMed] [Google Scholar]
  • 9.Yu S, Li C, Hou XG, Hou WK, Dong JJ, Lei SUN, Tang KX, Bin WANG, Jun SONG, Hui LI, Wang KX. Differentiation of bone marrow-derived mesenchymal stem cells from diabetic patients into insulin-producing cells in vitro. Chin Med J. 2007;120(9):771–6. doi: 10.1097/00029330-200705010-00007. [DOI] [PubMed] [Google Scholar]
  • 10.Murphy MB, Moncivais K, Caplan AI. Mesenchymal stem cells: environmentally responsive therapeutics for regenerative medicine. Exp Mol Med. 2013;45(11):.e54. doi: 10.1038/emm.2013.94. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 11.Stagg J. Immune regulation by mesenchymal stem cells: two sides to the coin. Tissue Antigens. 2007;69(1):1–9. [DOI] [PubMed]
  • 12.Figueroa FE, Carrión F, Villanueva S, Khoury M. Mesenchymal stem cell treatment for autoimmune diseases: a critical review. Biol Res. 2012;45(3):269–77. [DOI] [PubMed]
  • 13.Cho J, D’Antuono M, Glicksman M, Wang J, Jonklaas J. A review of clinical trials: Mesenchymal stem cell transplant therapy in type 1 and type 2 diabetes mellitus. Am J Stem Cells. 2018;7(4):82. [PMC free article] [PubMed]
  • 14.Favaro E, Carpanetto A, Lamorte S, Fusco A, Caorsi C, Deregibus MC, Bruno S, Amoroso A, Giovarelli M, Porta M, Perin PC. Human mesenchymal stem cell-derived microvesicles modulate T cell response to islet antigen glutamic acid decarboxylase in patients with type 1 diabetes. Diabetologia. 2014;57(8):1664–73. [DOI] [PubMed]
  • 15.Favaro E, Carpanetto A, Caorsi C, Giovarelli M, Angelini C, Cavallo-Perin P, Tetta C, Camussi G, Zanone MM. Human mesenchymal stem cells and derived extracellular vesicles induce regulatory dendritic cells in type 1 diabetic patients. Diabetologia. 2016;59(2):325–33. doi: 10.1007/s00125-015-3808-0. [DOI] [PubMed] [Google Scholar]
  • 16.Carlsson PO, Schwarcz E, Korsgren O, Le Blanc K. Preserved β-cell function in type 1 diabetes by mesenchymal stromal cells. Diabetes. 2015;64(2):587–92. doi: 10.2337/db14-0656. [DOI] [PubMed] [Google Scholar]
  • 17.Zhao Y, Jiang Z, Zhao T, Ye M, Hu C, Yin Z, Li H, Zhang Y, Diao Y, Li Y, Chen Y. Reversal of type 1 diabetes via islet β cell regeneration following immune modulation by cord blood-derived multipotent stem cells. BMC Med. 2012;10(1):3. doi: 10.1186/1741-7015-10-3. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 18.Bansal R, Jain A. Current overview on dental stem cells applications in regenerative dentistry. J Nat Sci Biol Med. 2015;6(1):29. [DOI] [PMC free article] [PubMed]
  • 19.Kaku M, Komatsu Y, Mochida Y, Yamauchi M, Mishina Y, Ko CC. Identification and characterization of neural crest-derived cells in adult periodontal ligament of mice. Arch Oral Biol. 2012;57(12):1668–75. [DOI] [PMC free article] [PubMed]
  • 20.Zhu W, Liang M. 2015. Periodontal ligament stem cells: current status, concerns, and future prospects. Stem Cells Int. 2015. [DOI] [PMC free article] [PubMed]
  • 21.Klyushnenkova E, Mosca JD, Zernetkina V, Majumdar MK, Beggs KJ, Simonetti DW, Deans RJ, McIntosh KR. T cell responses to allogeneic human mesenchymal stem cells: immunogenicity, tolerance, and suppression. J Biomed Sci. 2005;12(1):47–57. [DOI] [PubMed]
  • 22.Obermaier B, Dauer M, Herten J, Schad K, Endres S, Eigler A. Development of a new protocol for 2-day generation of mature dendritic cells from human monocytes. Biol Proced Online. 2003;5(1):197. [DOI] [PMC free article] [PubMed]
  • 23.Tran HLB, Doan VN, Le HTN, Ngo LTQ. Various methods for isolation of multipotent human periodontal ligament cells for regenerative medicine. In Vitro Cell Dev Biol Anim. 2014;50(7):597–602. [DOI] [PubMed]
  • 24.Abuarqoub DA, Aslam N, Barham RB, Ababneh NA, Shahin DA, Al-oweidi AA, Jafar HD, Al-Salihi MA, Awidi AS. The effect of platelet lysate in culture of PDLSCs: an in vitro comparative study. PeerJ. 2019;7:.e7465. doi: 10.7717/peerj.7465. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 25.Giannoukakis N, Trucco M. Dendritic cell therapy for Type 1 diabetes suppression. Immunotherapy. 2012;4(10):1063–74. doi: 10.2217/imt.12.76. [DOI] [PubMed] [Google Scholar]
  • 26.Koch NF, Stanzl U, Jennewein P, Janke K, Heufler C, Kämpgen E, Romani N, Schuler G. High level IL-12 production by murine dendritic cells: upregulation via MHC class II and CD40 molecules and downregulation by IL-4 and IL-10. J Exp Med. 1996;184(2):741–6. doi: 10.1084/jem.184.2.741. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 27.Caux C, Massacrier C, Vanbervliet B, Dubois B, Van Kooten C, Durand I, Banchereau J. Activation of human dendritic cells through CD40 cross-linking. J Exp Med. 1994;180(4):1263–72. doi: 10.1084/jem.180.4.1263. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 28.Pletinckx K, Döhler A, Pavlovic V, Lutz MB. Role of dendritic cell maturity/costimulation for generation, homeostasis, and suppressive activity of regulatory T cells. Front Immunol. 2011;2:39. doi: 10.3389/fimmu.2011.00039. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 29.Thomas IJ, de Marquesini LGP, Ravanan R, Smith RM, Guerder S, Flavell RA, Wraith DC, Wen L, Wong FS. CD86 has sustained costimulatory effects on CD8 T cells. J Immunol. 2007;179(9):5936–46. doi: 10.4049/jimmunol.179.9.5936. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 30.Aerts-Toegaert C, Heirman C, Tuyaerts S, Corthals J, Aerts JL, Bonehill A, Thielemans K, Breckpot K. CD83 expression on dendritic cells and T cells: correlation with effective immune responses. Eur J Immunol. 2007;37(3):686–95. doi: 10.1002/eji.200636535. [DOI] [PubMed] [Google Scholar]
  • 31.Chomarat P, Banchereau J, Davoust J, Palucka AK. IL-6 switches the differentiation of monocytes from dendritic cells to macrophages. Nat Immunol. 2000;1(6):510. [DOI] [PubMed]
  • 32.Pasare C, Medzhitov R. Toll pathway-dependent blockade of CD4 + CD25 + T cell-mediated suppression by dendritic cells. Science. 2003;299(5609):1033–6. doi: 10.1126/science.1078231. [DOI] [PubMed] [Google Scholar]
  • 33.Wunderlich FT, Ströhle P, Könner AC, Gruber S, Tovar S, Brönneke HS, Juntti-Berggren L, Li LS, Van Rooijen N, Libert C, Berggren PO. Interleukin-6 signaling in liver-parenchymal cells suppresses hepatic inflammation and improves systemic insulin action. Cell Metabol. 2010;12(3):237–49. doi: 10.1016/j.cmet.2010.06.011. [DOI] [PubMed] [Google Scholar]
  • 34.Li MO, Flavell RA. TGF-β: a master of all T cell trades. Cell. 2008;134(3):392–404. doi: 10.1016/j.cell.2008.07.025. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 35.Shevach EM, Tran DQ, Davidson TS, Andersson J. The critical contribution of TGF-β to the induction of Foxp3 expression and regulatory T cell function. Eur J Immunol. 2008;38(4):915–7. doi: 10.1002/eji.200738111. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 36.Phillips B, Giannoukakis N, Trucco M. Dendritic cell-based therapy in Type 1 diabetes mellitus. Expert Rev Clin Immunol. 2009;5(3):325–39. doi: 10.1586/eci.09.8. [DOI] [PubMed] [Google Scholar]
  • 37.Giannoukakis N, Trucco M. Dendritic cell therapy for Type 1 diabetes suppression. Immunotherapy. 2012; 4(10), 1063–1074. [DOI] [PubMed]
  • 38.Herold KC, Bundy BN, Long SA, Bluestone JA, DiMeglio LA, Dufort MJ, Gitelman SE, Gottlieb PA, Krischer JP, Linsley PS, Marks JB. An anti-CD3 antibody, teplizumab, in relatives at risk for type 1 diabetes. N Engl J Med. 2019;381(7):603–13. doi: 10.1056/NEJMoa1902226. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Journal of Diabetes and Metabolic Disorders are provided here courtesy of Springer

RESOURCES