%0 Journal Article
%T The ¦Ã¦ÄTCR combines innate immunity with adaptive immunity by utilizing spatially distinct regions for agonist selection and antigen responsiveness
%J -
%D 2018
%R https://doi.org/10.1038/s41590-018-0253-5
%X T lymphocytes expressing ¦Ã¦Ä T cell antigen receptors (TCRs) comprise evolutionarily conserved cells with paradoxical features. On the one hand, clonally expanded ¦Ã¦Ä T cells with unique specificities typify adaptive immunity. Conversely, large compartments of ¦Ã¦ÄTCR+ intraepithelial lymphocytes (¦Ã¦Ä IELs) exhibit limited TCR diversity and effect rapid, innate-like tissue surveillance. The development of several ¦Ã¦Ä IEL compartments depends on epithelial expression of genes encoding butyrophilin-like (Btnl (mouse) or BTNL (human)) members of the B7 superfamily of T cell co-stimulators. Here we found that responsiveness to Btnl or BTNL proteins was mediated by germline-encoded motifs within the cognate TCR variable ¦Ã-chains (V¦Ã chains) of mouse and human ¦Ã¦Ä IELs. This was in contrast to diverse antigen recognition by clonally restricted complementarity-determining regions CDR1¨CCDR3 of the same ¦Ã¦ÄTCRs. Hence, the ¦Ã¦ÄTCR intrinsically combines innate immunity and adaptive immunity by using spatially distinct regions to discriminate non-clonal agonist-selecting elements from clone-specific ligands. The broader implications for antigen-receptor biology are considered
%U https://www.nature.com/articles/s41590-018-0253-5