T Cells Engaging the Conserved MHC Class Ib Molecule Qa-1b with TAP-Independent Peptides Are Semi-Invariant Lymphocytes.

ABSTRACT: The HLA-E homolog in the mouse (Qa-1b) is a conserved MHC class Ib molecule presenting monomorphic peptides to germline-encoded natural killer receptor CD94/NKG2A. Previously, we demonstrated the replacement of this canonical peptide by a diverse peptidome upon deficiency of the TAP peptide transporter. Analysis of this Qa-1b-restricted T cell repertoire against these non-mutated neoantigens revealed characteristics of conventional hypervariable CD8+ T cells, but also of invariant T cell receptor (TCR)αβ T cells. A shared TCR Vα chain was used by this subset in combination with a variety of Vβ chains. The TCRs target peptide ligands that are conserved between mouse and man, like the identified peptide derived from the transcriptional cofactor Med15. The thymus selection was studied in a TC

SUBMITTER: Doorduijn EM 

PROVIDER: S-EPMC5788890 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature