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The biology and functional importance of MAIT cells

Abstract

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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Fig. 1: A timeline highlighting some of the key events in the field of MAIT cell biology.
Fig. 2: MR1-restricted T cell characteristics in humans and mice.
Fig. 3: MAIT cell activation.
Fig. 4: Development of MAIT cells in mice and humans.

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Acknowledgements

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).

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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.

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Godfrey, D.I., Koay, HF., McCluskey, J. et al. The biology and functional importance of MAIT cells. Nat Immunol 20, 1110–1128 (2019). https://doi.org/10.1038/s41590-019-0444-8

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