Self-MHC-restricted peptides recognized by an alloreactive T lymphocyte clone

摘要: Alloreactive T lymphocytes are readily detected in unprimed animals although they have never encountered the alloantigen before. This well-established phenomenon is usually explained with assumption that a self-MHC molecule complexed defined peptide resembles allo-MHC another and induces corresponding cell specificities. Here, for first time support of this hypothesis, self-MHC-restricted peptides described clone was induced allo-MHC. The allo-MHC-specific CTL 2C derived from H-2b mouse recognizes H-2Ld naturally occurring endogenous LSPFPFDL. H-2Kb shown to be involved positive selection its TCR, associated MHC implicated process. To identify such peptides, positional scanning random libraries combined an iterative approach employed. Several active were found most efficient, SIYRYYGL, chosen further studies. Recognition by two MHC-peptide adducts + LSPFPFDL SIYRYYGL mediated same TCR appears similarly efficient as concluded inhibition experiments Id-specific Ab. CTLs SIYRYYGL-primed mice respond reciprocal cross-reactivity suggests structural features shared complexes.