Supplement of Exogenous IL2 Abrogates Induction of Tolerance in Drug‐Induced T Cell Proliferation

Abstract

An intravenous injection of large doses of semi‐synthetic penicillin, sulbenicillin (SBPC) 7 days before immunization induced immunological tolerance of lymphocyte proliferative response to SBPC. This nonresponsiveness of the tolerant lymph node cells to SBPC was not changed into responsiveness by removing the Lyt‐2+ suppressor type T (Ts) subset. However, an in vivo interleukin 2 (IL2) treatment changed the nonresponsiveness of the tolerant Lyt‐1+2– helper type T (Th) cells into responsiveness. These results suggest that the nonresponsiveness of the tolerant lymph node cells is due to clonal anergy or deletion of the Lyt‐1+2– Th cells rather than to involvement of Lyt‐2+ Ts cells, and support the hypothesis that tolerance is a consequence of IL2 deficit during the T cell recognition of antigen.