The in vitro effects of D-penicillamine upon anti-AChR production by thymic and peripheral blood lymphocytes from patients with myasthenia gravis.

D-Penicillamine added to lymphocyte cultures from myasthenia gravis patients infrequently and inconsistently stimulated anti-AChR production. This usually occurred in the presence of pokeweed mitogen (PWM), and often only at a single concentration of D-penicillamine which varied among patients. The change was typically paralleled by an increase in total IgG production of similar magnitude, suggesting that the effect was nonspecific. D-penicillamine did not affect AChR expression in cultured thymic adherent cells. These data provide no evidence that penicillamine induces myasthenia gravis by direct stimulation of anti-AChR antibody-producing cells.