IL-2 normalizes defective suppressor T cell function of patients with systemic lupus erythematosus in vitro.

During autologous mixed lymphocyte reaction (AMLR) both helper and suppressor T cells capable of regulating B cell responses are generated. The proliferative response of T cells as well as the generation of T suppressor cells in the AMLR of patients with active systemic lupus erythematosus (SLE) is diminished. In contrast, the T helper cells generated in the AMLR show a hyperactivity. The diminished HLA-class II antigen expression observed on non-T cells of SLE origin was restored by treatment of the cells with gamma-interferon (gamma-IFN). When tested by immunoglobulin secretion, gamma-IFN enhanced T helper cell activity but failed to affect T cell proliferation and T suppressor cell generation in the AMLR derived from patients with SLE. Human recombinant interleukin 2 restores both the proliferative response of T cells and the induction of T suppressor cells in AMLR.