Cytotoxic T cells learn specificity for self H-2 during differentiation in the thymus.

摘要: CELL mediated immune reactions in mice involving cytotoxic thymus derived lymphocytes have two important features; they are antigen-specific1 and the structures coded for by major murine histocompatibility gene complex (H–2) play an part killer cell-target cell interaction1. This finding is not unique to since it has also been reported rats, humans chickens2–4. Two hypotheses suggested explain this dual specificity of T cells; one proposes that cells possess separate structures, which recognises self H–2 other a non-H–2 antigen (dual recognition). The hypothesis receptor modified (modified self)1,5. Evidence test these was sought preparing chimaeras made reconstituting lethally irradiated F1 with bone marrow stem parent (Parent→F) refs 6–8) or neonatally tolerant mice9 (mice parental type injected as neonates). As result, Parent → chimaeric lysed infected trinitrophenyl (TNP)-modified targets both types, suggesting antigens were involved lytic interaction. In contrast, from did lyse incompatible parent9. Although results can be explained postulating single receptor, fit recognition hypothesis6–10. Bevan shown (A × B)F1 Parental A recipient generated preferentially against minor association haplotype A; he concluded host determines restriction either through thymic selection process proposed Jerne alternatively presentation mechanism.