Mucosal-associated invariant T cells for cancer immunotherapy

Human mucosal-associated invariant T (MAIT) cells are charac-terized by their expression of an invariant TCR a chain Va7.2-Ja33/Ja20/Ja12 paired with a restricted TCR b chain. MAIT cells recognize microbial peptides presented by the highly conserved MHC class I-like molecule MR1 and bridge the innate and acquired immune systems to mediate augmented immune responses. Upon activation, MAIT cells rapidly proliferate, pro-duce a variety of cytokines and cytotoxic molecules, and trigger efficient antitumor immunity. Administration of a representa-tive MAIT cell ligand 5-OP-RU effectively activates MAIT cells and enhances their antitumor capacity. In this review, we intro-duce MAIT cell biology and their importance in antitumor im-munity, summarize the current development of peripheral blood mononuclear cell-derived and stem cell-derived MAIT cell prod-ucts for cancer treatment, and discuss the potential of genetic en-gineering of MAIT cells for off-the-shelf cancer immunotherapy.

Automated summary

Human mucosal-associated invariant T (MAIT) cells express an invariant TCR a chain and a restricted TCR b chain, bridging the innate and acquired immune systems. MAIT cells recognize microbial peptides presented by MR1 and play a role in antitumor immunity. Activation of MAIT cells leads to proliferation, cytokine production, and efficient antitumor immune response. This review highlights the biology of MAIT cells, their importance in antitumor immunity, and potential applications in cancer treatment.