Immunological effects of D-penicillamine during experimental induced inflammation in rats

Administration of D-penicillamine (50 mg/kg/day orally) to rats with adjuvant arthritis for up to 42 days significantly modified the incorporation of 3H-thymidine (3H-TdR) in concanavalin A (Con A)-stimulated lymph node cells. Treatment with D-penicillamine abolished the ability of macrophages from arthritic rats to inhibit lymphocyte responsiveness to Con A and lipopolysaccharide (LPS) 14 days after the induction of the disease. Increased T-cell responsiveness to Con A was found from day 14 to 35 in cultures of unseparated and adherent-cell-depleted lymph node cells from D-penicillamine-treated arthritic rats. B-cell responsiveness to LPS was not affected. Experiments with bovine serum albumin gradient-separated lymph node cells confirmed these findings and indicated that treatment with D-penicillamine may specifically enhance T-helper cell responsiveness to Con A. It is suggested that administration of D-penicillamine may interfere with macrophage function during the course of an immunologically induced chronic inflammation, leading to an increased response of T-helper cells. The theoretical implications of these findings are discussed.