Human TRAV1-2-negative MR1-restricted T cells detect S. pyogenes and alternatives to MAIT riboflavin-based antigens.
Nat Commun
; 7: 12506, 2016 08 16.
Article
in En
| MEDLINE
| ID: mdl-27527800
ABSTRACT
Mucosal-associated invariant T (MAIT) cells are thought to detect microbial antigens presented by the HLA-Ib molecule MR1 through the exclusive use of a TRAV1-2-containing TCRα. Here we use MR1 tetramer staining and ex vivo analysis with mycobacteria-infected MR1-deficient cells to demonstrate the presence of functional human MR1-restricted T cells that lack TRAV1-2. We characterize an MR1-restricted clone that expresses the TRAV12-2 TCRα, which lacks residues previously shown to be critical for MR1-antigen recognition. In contrast to TRAV1-2(+) MAIT cells, this TRAV12-2-expressing clone displays a distinct pattern of microbial recognition by detecting infection with the riboflavin auxotroph Streptococcus pyogenes. As known MAIT antigens are derived from riboflavin metabolites, this suggests that TRAV12-2(+) clone recognizes unique antigens. Thus, MR1-restricted T cells can discriminate between microbes in a TCR-dependent manner. We postulate that additional MR1-restricted T-cell subsets may play a unique role in defence against infection by broadening the recognition of microbial metabolites.
Full text:
1
Database:
MEDLINE
Main subject:
Riboflavin
/
Streptococcus pyogenes
/
Histocompatibility Antigens Class I
/
Minor Histocompatibility Antigens
/
T-Lymphocyte Subsets
/
Receptors, Antigen, T-Cell, alpha-beta
/
Antigens
Type of study:
Diagnostic_studies
Limits:
Humans
Language:
En
Year:
2016
Type:
Article