[In vitro study of the primary antibody response of circulating lymphocytes in patients with chronic inflammatory rheumatism].

We have studied the in vitro antibody response to a hapten of peripheral blood lymphocytes from 26 patients with rheumatoid arthritis and 7 ankylosing spondylitis. These patients had never received immunosuppressor drugs before or corticosteroids during the month before the test. They had failed to receive aspirin or non-steroid anti-inflammatory drugs for 72 hours before blood sampling. The control groups included respectively 38 healthy subjects and 24 patients hospitalized for non inflammatory disease. The antibody response of ankylosing spondylitis patients is comparable to that of controls ; on the opposite the response of patients with rhumatoid arthritis is significantly depressed in comparison with the three other groups. The weak response of lymphocytes in arthritis is not due to increased cell death in culture or to modified kinetics of the antibody response or to the appearance of a IgG secondary type response or a in vivo pre-activation. The lymphocytes of arthritis patients do not inhibit the response of normal lymphocytes when they are co-cultured. The observed response is identical to that obtained when control patient lymphocytes are co-cultured with normal lymphocytes. The function of suppressor T cells induced by Con A seems normal in spondylitis and arthritis.