Drug protein interactions.

Effects of two antirheumatic drugs, D-penicillamine and (-)-2,3,5,6-tetrahydro-6-phenylimidazo[2,1-b] thiazole (levamisole), on some human serum proteins with specific function are reported. Drug effects on the interaction corticosterone-corticosteroid binding globulin (CBG) in vitro were investigated especially by polyacrylamide gel electrophoresis. A quantitative modification of the % of corticosterone bound to CBG was noted. Drug effects on immunoglobulins involved in immune processes are described. Comparative studies by polyacrylamide gel electrophoresis and immunoelectrophoresis showed that addition of levamisole to the serum in vitro may give results different from those obtained when D-penicillamine was added. D-Penicillamine treatment was shown to induce principally a modification of Ig M, whereas levamisole caused a modification of Ig G and Ig A. On the other hand, "abnormal" fractions were noted by disc polyacrylamide gel electrophoresis when the serum was incubated with levamisole.