Table 2.

Pros and cons of using different types of cells in cancer immunotherapy.

Cell Therapy	Pros	Cons
Conventional T cell	Abundant source Easy to expand in vitro Scalable and standardized quality controls for manufacturing	Time-consuming and costly MHC dependent T cell exhaustion GVHD Low ability of trafficking and infiltrating into solid tumors
NK cell	No need for previous antigen priming Multiple innate activating receptors that can mediate killing MHC independent No GVHD	Low persistence in the absence of cytokine Low number in patients Low ability of trafficking and infiltrating into solid tumors
iNKT cell	Innate and adaptive features Invariant TCR recognizes lipid antigens presented by CD1d No GVHD Low toxicities	Low number in patients May have immunosuppressive properties (Th2, Th17) Limited clinical data with CAR-iNKT cells
γδT cell	Innate and adaptive features MHC independent No GVHD Low toxicities	Extremely low number in patients May have immunosuppressive properties (γδ T17, Vδ1 γδ T cells, γδ Treg) Limited clinical data with CAR- γδT cells
MAIT cell	Solid tumor-infiltrating capacity Direct anti-tumor cytotoxicity both in vitro and in vivo Resistant to tumor antigen escape	Unclear mechanisms in suppressing tumor Lack of clinical data with CAR-MAIT cells
Macrophage cell	Penetration into solid tumors Phagocytosis of tumor cells and innate immune response No GVHD Cross present antigens to αβ T cells	Poor proliferation both in vitro and in vivo May have immunosuppressive properties (M2) Limited clinical data with CAR-macrophage cells