Table 2.

Cell-based therapies of solid tumors.

Cell Type	Cell Therapy	Description of Cellular Therapy	References
Macrophages	Macrophage-based drug delivery system	The research is the biological phenomenon referred to TRAnsfer of Iron-binding protein (TRAIN). This is based on the direct transfer of the ferritin-drug complex from macrophages to cancer cells. The utilization of macrophages in this context serves as a carrier used for transport of the ferritin-drug complex to hypoxic regions that would otherwise remain inaccessible to alternative therapeutic approaches.	[219,220,221]
	CAR-macrophages for the treatment of HER2-overexpressing solid tumors	Non-replicating adenoviral vectors can effectively deliver CARs to human macrophages. Injection of adenovirus triggers a pro-inflammatory tumor microenvironment (TME) and activates macrophages towards the M1 phenotype. CAR-expressing macrophages transduced with adenovirus can more effectively activate T lymphocytes, significantly prolong the survival curve, and reduce metastasis formation.	[102]
Dendritic cells	Pulsed DC vaccination	Ex vivo DCs are generated from circulating blood precursors or bone marrow progenitor cells. They are educated (pulsed) with the patient’s tumor antigens or tumor-derived mRNA and then introduced back to the patients.	[222,223,224,225,226]
	Hybrid cells vaccination	Induction of tumor-specific CTL by a vaccine made with a fusion of autologous/allogenic DCs and tumor cells extracted from the patient.	[227]
Neutrophils	Neutrophil activation	Ex vivo neutrophil-activating therapy consisting of TNF, anti-CD40, and tumor-binding antibody allows rapid recruitment of neutrophils to tumors.	[163]
	Neutrophil-based drug delivery system	Transport of anticancer drug-loaded nanomaterials by neutrophils.	[163,167,228]
	Neutrophil-based photodynamic therapy platform	Transport of nanoparticles loaded with photodynamic agents or antibodies by neutrophils into cancer.	[168,229,230,231]
	Chimeric antigen receptors neutrophils (CAR-Neu)	Pluripotent stem cells are genetically modified through the integration of CARs and subsequently differentiated into neutrophils with enhanced cytotoxic activity specifically targeting cancer cells.	[232]
T lymphocytes	Chimeric antigen receptors T cells (CAR-T)	Isolation of peripheral T cells through apheresis following transduction with a CAR against tumor antigen. CARs are designed to aid the T cell attachment to the specific proteins on the surface of the cancer cells.	[233,234]
	Tumor-infiltrating lymphocytes therapy (TIL)	Isolation of tumor-infiltrating lymphocytes, selection of lymphocytes with antitumor activity, and their proliferation and injection into patients.	[235,236]
	Cytokine-induced killer (CIK) cells (natural killer-like T cells)	Ex vivo expansion of peripheral blood mononuclear cells with anti-CD3 antibodies, IL-2, and IFN-γ. Cytotoxity of those cells is based on contact of natural killer group 2 member D (NKG2D) with its ligand on tumor cells and the perforin-mediated pathways.	[237]
	Gene-modified T cells expressing novel T cell receptors (TCRs)	Isolation of peripheral T cells through apheresis following transduction with a TCR against tumor antigen.	[71]
	T cell-based drug delivery	Drug-loaded liposomes/multilamellar lipid NPs/lipid-coated polymer nanoparticles.	[238]
B lymphocytes	B cell antigen loading and activation	Ex vivo antigen loading and activation of B lymphocytes, which further enhances T cell activation.	[181,182,183,239]
	Hybrid cell vaccination—B cells	Electric fusion of the patient’s tumor cells with the stimulated autologous/allogenic B cells. Those hybrid cells present tumor-associated antigens and allo-MHC molecules.	[189,240]
Natural killer cells	Allogenic NK cell infusions with IL-2 and chemotherapeutics	Haploidentical, related-donor NK cell infusions along with IL-2 injections and cyclophosphamide/methylprednisolone or fludrabine or cyclophosphamide/fludrabine.	[241]
	Adoptive immunotherapy with NK-92 cells	The NK-92 cell line is derived from NK cell lymphoma. Those highly cytotoxic allogenic cells, after irradiation, are injected into the patient.	[242]
	CAR-NK/CAR-NK-92	NK cells or NK-92 cells transduced with retroviral vectors so that they express a chimeric antigen receptor specific to tumor antigens.	[243,244,245]
Cancer-associated adipocytes	Adipocyte-based drug delivery system	Adipocytes are used to encapsulate anticancer drugs in combination with rumenic acid. The drug is subsequently delivered to cancer cells through the activation of lipid metabolic pathways.	[217]
Endothelial cells	Endothelial progenitor cells (EPCs) vehicles for cancer gene therapy	Ex vivo expansion of EPCs and their transduction with viral vectors so that they express suicide genes or Il-2	[246]
	Endothelial progenitor cells (EPCs) vehicles as oncolytic virus transporters	Ex vivo expansion of EPCs and their modification with viral vectors to produce oncolytic viruses directly in the tumor	[247]