Specificity and flexibility in thymic selection

摘要: During positive selection, developing thymocytes are rescued from programmed cell death by T-cell receptor (TCR)-mediated recognition of major histocompatibility complex (MHC) molecules. MHC-bound peptides contribute to this process. Recently we identified individual MHC-binding which can induce selection a single TCR. Here examine peptide fine specificity in selection. These data suggest that direct TCR-peptide interaction occurs during event, and strengthens the correlation between selecting TCR antagonists. Certain positively weakly antigenic. We demonstrate 'educated' on such specifically non-responsive it have decreased CD8 expression levels. Similar reduction mature T cells converts agonist into antagonist. indicate may maintain self-tolerance towards ligand regulating co-receptor expression.