Promiscuous recognition of MR1 drives self-reactive mucosal-associated invariant T cell responses
Mucosal-associated invariant T (MAIT) cells use canonical semi-invariant T cell receptors (TCR) to recognize microbial riboflavin precursors displayed by the antigen-presenting molecule MR1. The extent of MAIT TCR crossreactivity toward physiological, microbially unrelated antigens remains underexpl...
Saved in:
Published in | The Journal of experimental medicine Vol. 220; no. 9 |
---|---|
Main Authors | , , , , , , , , , , , , , , , , , , , , , , , , , , , , , |
Format | Journal Article |
Language | English |
Published |
United States
Rockefeller University Press
04.09.2023
|
Subjects | |
Online Access | Get full text |
Cover
Loading…
Summary: | Mucosal-associated invariant T (MAIT) cells use canonical semi-invariant T cell receptors (TCR) to recognize microbial riboflavin precursors displayed by the antigen-presenting molecule MR1. The extent of MAIT TCR crossreactivity toward physiological, microbially unrelated antigens remains underexplored. We describe MAIT TCRs endowed with MR1-dependent reactivity to tumor and healthy cells in the absence of microbial metabolites. MAIT cells bearing TCRs crossreactive toward self are rare but commonly found within healthy donors and display T-helper-like functions in vitro. Experiments with MR1-tetramers loaded with distinct ligands revealed significant crossreactivity among MAIT TCRs both ex vivo and upon in vitro expansion. A canonical MAIT TCR was selected on the basis of extremely promiscuous MR1 recognition. Structural and molecular dynamic analyses associated promiscuity to unique TCRβ-chain features that were enriched within self-reactive MAIT cells of healthy individuals. Thus, self-reactive recognition of MR1 represents a functionally relevant indication of MAIT TCR crossreactivity, suggesting a potentially broader role of MAIT cells in immune homeostasis and diseases, beyond microbial immunosurveillance. |
---|---|
Bibliography: | ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 A. Chancellor and R. Simmons contributed equally to this paper. Disclosures: R. Simmons, V. Karuppiah, R. Suckling, M. Hock, and M. Lepore reported personal fees from Immunocore Ltd. during the conduct of the study and personal fees from Immunocore Ltd. outside the submitted work. No other disclosures were reported. D.K. Cole, G. De Libero, and M. Lepore contributed equally to this paper. |
ISSN: | 0022-1007 1540-9538 |
DOI: | 10.1084/jem.20221939 |