D-penicillamine, lymphocytes, and macrophages: an account of experimental investigations in vivo.

A short oral treatment with D-penicillamine of normal rats increased responsiveness of spleen and lymph node lymphocytes to concanavalin A, depending on the presence of functionally intact macrophages. This effect vanished after 2 to 3 wk despite continued treatment. In adjuvant arthritic rats, a suppressed response of lymph node lymphocytes occurs concomitantly with the development of the secondary lesion. This inhibition caused by suppressive macrophage activity was abolished by D-penicillamine treatment, which enhanced T helper cell function. This effect disappeared when permanent crippling developed with residual minimal inflammatory reaction. These findings may give further insight into the drug's effects and side effects.