1980 Volume 29 Issue 4 Pages 171-178
Twenty-two untreated patients with systemic lypus erythematosus (SLE) were studied for the in vitro responsiveness of their peripheral blood lymphocytes to phytomitogen such as phytohemagglutinin (PHA), concanavalin A (Con A) or pokeweed mitogen (PWM), and also tested for the presence of serum factor(s) which could inhibit mitogenic responses of normal cells. There was marked reduction in the responses of lymphocytes from a group of patients with active SLE to all these mitogens in comparison with the responses of cells from normal individuals. When the disease activity decreased, the perfectly normal response to either PHA or Con A was observed. In contrast, the response to PWM in most patients remained to be impaired during disease quiescence. We have also found inhibitory factor(s) present in the sera of patients with active SLE which could alter the mitogenic responses of normal cells. The inhibitory effect of SLE sera was most profound in the response to PWM. Of interest is that cold type antibodies to a non-T cell population were also found in 56% of the selected sera which had the inhibitory activity. Defective responsiveness of SLE lymphocytes to PWM might be the result of the effects of such antibody activity in vivo.
