MAIT Cells: Partners or Enemies in Cancer Immunotherapy?

Abstract

A recent boom in mucosal-associated invariant T (MAIT) cell research has identified relationships between MAIT cell abundance, function, and clinical outcomes in various malignancies. As they express a variety of immune checkpoint receptors and ligands, and possess strong cytotoxic functions, MAIT cells are an attractive new subject in the field of tumor immunology. MAIT cells are a class of innate-like T cells that express a semi-invariant T cell antigen receptor (TCR) that recognizes microbially derived non-peptide antigens presented by the non-polymorphic MHC class-1 like molecule, MR1. In this review, we outline the current (and often contradictory) evidence exploring MAIT cell biology and how MAIT cells impact clinical outcomes in different human cancers, as well as what role they may have in cancer immunotherapy.

Emerging Roles of Mucosal-Associated Invariant T Cells in Rheumatology

“…Because MAIT cells are also involved in a number of inflammatory and autoimmune disorders as well as malignancies, they are attractive targets for therapeutic approaches (39)(40)(41)(42)(43). The present paper aims to review the evidence indicating that MAIT cells may contribute to the pathogenesis of rheumatic diseases due to the possible role of MAIT cells in SLE, RA, PsA, ankylosing spondylitis (AS), SSc, pSS, systemic vasculitis, polymyalgia rheumatica and dermatomyositis (Table 1).…”

Regulation and Functions of Protumoral Unconventional T Cells in Solid Tumors

“…Nevertheless, UT cell-based cancer immunotherapies have already been considered. To date, UT cell-based clinical trials have shown limited success, although such strategies were proven feasible and safe [ 23 , 199 , 200 , 201 ]. The limited positive outcome observed with UT cell-based cancer immunotherapies may be linked to the reduced proportion of UT cells in cancer patients and/or the emergence of exhausted phenotype upon repeated stimulations.…”

AllergoOncology: Role of immune cells and immune proteins

“…As far their effects, tumour-infiltrating MAIT cells show reduced IFN-γ and TNF-α generation, with augmented IL-17 production, a cytokine able to increase to tumour angiogenesis. 69 As for the effects of these cells on allergic diseases, several findings have demonstrated that MAIT cells may be involved in asthma. A study reported that augmented rates of MAIT cells in children was correlated with a decreased risk of asthma in subse- therefore, they are both a source and a target of VEGF.…”