In recent years, a population of unconventional T cells called ‘mucosal-associated invariant T cells’ (MAIT cells) has captured the attention of immunologists and clinicians due to their abundance in humans, their involvement in a broad range of infectious and non-infectious diseases and their unusual specificity for microbial riboflavin-derivative antigens presented by the major histocompatibility complex (MHC) class I–like protein MR1. MAIT cells use a limited T cell antigen receptor (TCR) repertoire with public antigen specificities that are conserved across species. They can be activated by TCR-dependent and TCR-independent mechanisms and exhibit rapid, innate-like effector responses. Here we review evidence showing that MAIT cells are a key component of the immune system and discuss their basic biology, development, role in disease and immunotherapeutic potential.
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This work was supported by the National Health and Medical Research Council of Australia (NHMRC; 1113293 and 1140126); the Australian Research Council (ARC; CE140100011) and the Cancer Council of Victoria (#). DIG is supported by NHMRC Senior Principal Research Fellowship (1117766). H-F.K is supported by an NHMRC ECF Fellowship (1160333).
J.M. is a named inventor on patents: US 10011602B2 (PCT No. WO2014/005194) The University of Melbourne, University of Queensland and Monash University; US 10245 262B2 (PCT No. WO201/149130) The University of Melbourne, University of Queensland and Monash University.
Peer review information: Jamie D. K. Wilson was the primary editor on this article and managed its editorial process and peer review in collaboration with the rest of the editorial team.
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