Studies of immune functions of patients with systemic lupus erythematosus. T-cell subsets and antibodies to T-cell subsets.
Antibodies to T cells present in the plasma of patients with active systemic lupus erythematosus (SLE) plus complement are able to eliminate concanavalin A-induced suppressor function for the proliferative responses of T cells to allogeneic lymphocytes (MLR) and of B cells to pokeweed mitogen (PWM). Such antibodies were found to be effective in eliminating suppressor function only when T cells were treated before activation; there was no effect when treatment was performed after activation. These studies indicate that the antibodies preferentially interact with a T cell necessary for the generation of suppressor cells, rather than with mature, activated suppressor cells. Studies of individual SLE patients indicate that the same defects observed in SLE T cells were induced in normal T cells by plasma from that patient. Such observations suggest that many T-cell defects associated with active SLE may not be intrinsic T-cell abnormalities, but, rather, secondary effects of anti-T-cell antibodies. Studies of the T-cell subpopulations responsible for suppression of the MLR and PWM responses indicate that only T gamma cells (T cells bearing receptors for the Fc portion of immunoglobulin [Ig]G) acted as precursors of suppressor cells for the MLR, whereas both T gamma and T non-gamma cells (T cells not bearing receptors for the Fc portion of IgG) could be activated to suppress the PWM response. Consistent with this observation, SLE anti-T-cell antibodies that preferentially killed T gamma cells preferentially eliminated suppressor cells for the MLR.
D001323:Autoantibodies / Q000276:immunology*; D001327:Autoimmune Diseases / Q000276:immunology*; D002478:Cells, Cultured; D003208:Concanavalin A / Q000494:pharmacology; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology; D008180:Lupus Erythematosus, Systemic / Q000276:immunology*; D011043:Pokeweed Mitogens / Q000494:pharmacology; D011952:Receptors, Concanavalin A / Q000276:immunology; D011961:Receptors, Fc / Q000276:immunology; D011975:Receptors, Mitogen / Q000276:immunology; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*
D001323:Autoantibodies; D007074:Immunoglobulin G; D011043:Pokeweed Mitogens; D011952:Receptors, Concanavalin A; D011961:Receptors, Fc; D011975:Receptors, Mitogen; D003208:Concanavalin A