A failure of T lymphocytes to produce interleukin 2 (IL-2) on restimulation may, In part, account for the specific unresponsiveness that accompanies incomplete activation. The evidence to support this has been derived predominantly from the investigation of the molecular basis of anergy in murine type 1 T cells. In this study, the effects of different tolerogenic signals delivered by specific peptide or Staphylococcus aureus enterotoxin on the ability of antigen- specific human T cells to produce lymphokines, both in the induction phase and in established antigen-specific non-responsiveness, have been examined. Although T cell proliferation was decreased by supraoptimal concentrations of specific peptide in the presence or absence of antigen presenting cells, IL-2, IL-4, and interferon gamma (IFN-γ) synthesis were comparable to that of activated T cells. The different tolerogenic signals, all capable of inhibiting proliferation, had selective effects on the secretion of these lymphokines during the induction phase of unresponsiveness. Restimulation of anergic T cells with an antigenic challenge failed to induce lymphokine production, with the exception of allergen-reactive T cells that secreted IFN-γ. This latter observation is relevant to the desensitization of specific responsiveness in allergic disease.
- T cells