A ROLE FOR ANTIGEN-PRESENTING CELLS AND BACTERIAL SUPERANTIGENS IN REVERSAL OF HUMAN T-LYMPHOCYTE ANERGY

The induction of anergy in T lymphocytes generates T cells incapable o f proliferation in response to a conventional antigenic stimulus. To i nvestigate the induction and maintenance of anergy in human T cells, w e used T cell-T cell presentation of myelin basic protein (MBP) or MBP synthetic peptides to induce anergy in vitro. Although anergic T cell s responded normally to interleukin-2 (IL-2), these T cells did not pr oduce IL-2 or IL-4 when peripheral blood mononuclear cells presented M BP or MBP peptides. Proliferation of anergic T cells was reduced by gr eater than 95% compared to nonanergic, control T cells. However, when autologous B cell lines were used to present MBP, anergy was partially reversed with a proliferation response about 50% of nonanergic levels . Bacterial superantigens also partially restored proliferation in ane rgic T cells following presentation by either B cell lines or macropha ge isolated from peripheral blood mononuclear cells. Anergic, MBP-reac tive T cells fully retained antigen-specific cytolytic activity agains t both B cell and T cell targets presenting MBP These results suggest that T cell proliferative anergy may be reversible with both the type of antigen-presenting cell and superantigens potentially contributing to the initiation or maintenance of an autoimmune response.