HLA-Dr+ T cells of the Leu 3 (helper) type infiltrate the kidneys of patients with systemic lupus erythematosus

The lineage and distribution of mononuclear cells infiltrating the kidneys of patients with systemic lupus erythematosus (SLE) have been investigated in cryostat tissue section of biopsies from 11 patients. The use of heterologous antisera and monoclonal antibodies has revealed that: (1) B lymphocytes and plasma cells are virtually absent in SLE kidney specimens; (2) The vast majority of mononuclear cells which infiltrate the interstitium are activated (HLA-Dr⁺) T cells (Leu 4⁺) presenting the helper (Leu 3⁺) phenotype; (3) T cells are absent in the glomeruli, where HLA-Dr⁺, SIgM^-, Leu 4^- elements with a macrophage like appearance can be observed.