Cold lymphocytotoxins in connective tissue disorders.
Sixty-eight patients with various connective tissue disorders, 5 relatives of patients and 26 members of staff from the Centre for Rheumatic Diseases were studied for the presence in their sera of cold lymphocytotoxic antibodies. Antibodies were found in 71 percent of patients with systemic lupus erythematosus, 27 per cent of patients with rheumatoid arthritis, 0 per cent of the small group of relatives and 3.8 per cent of the controls. Absorption studies did not show T or B specificity of the antibodies. The control group, working in close proximity to the patients or their sera did not show any increased incidence of antibodies as compared to control groups of other studies. Red blood cell anti I or HI was found in the sera of 28 per cent of those with cold lymphocytotoxic antibodies. No correlation was found between the presence of the antibodies and number of blood transfusions or pregnancies, increasing age, R3 titre or antinuclear factor.