Abstract
Lymphocytotoxic activity could be demonstrated in the sera of patients with systemic lupus erythematosus. The number of positive reactions varied with temperature of incubation. Lymphocytotoxicity was present in 88%, 49% and 11% of sera tested at 15°C, 22°C and 37°C respectively. At an incubation temperature of 22°C, the presence of the lymphocytotoxic antibody in the sera could be correlated with significantly higher titres of anti-nuclear factor, anti-single-stranded DNA and the histological appearance of active diffuse glomerulonephritis in renal biopsies.