Changes in B lymphocyte function in rheumatoid arthritis and lupus nephritis after total lymphoid irradiation.

Patients with rheumatoid arthritis and patients with lupus nephritis underwent total lymphoid irradiation (TLI). Peripheral blood mononuclear cells from these patients showed a decrease in pokeweed mitogen-induced immunoglobulin secretion after TLI. A defect in non-T cells contributed to the decreased response. No defect in the response of non-T cells to T cell-independent activators of B cells, Staphylococcus aureus Cowan 1 and Epstein-Barr virus, was observed after TLI. We conclude that TLI induces a selective deficit in B cells, which respond to T cell-dependent mitogen stimulation.