EFFECTS OF IPERIDINYLOXY)AMINO]-4'-DEMETHYLEPIPODOPHYLLOTOXIN ON IMMUNE FUNCTION IN MICE

,6'',6''-Tetramethyl-1''-piperidinyloxy)amino]-4'- demethylepipodophyl lotoxin (GP-7) 10-40 mg . kg-1 ip daily for 7 d reduced the specific a ntibody formation of splenocytes, serum agglutinin titer, and hemolysi n HC50 in mice immunized with SRBC. GP-7 inhibited the footpad delayed hypersensitivity reaction and decreased the weights of spleen and thy mus, but did not affect the phagocytic function of the peritoneal macr ophages. In vitro the proliferation of mouse splenic lymphocytes activ ated by Con A was markedly inhibited by GP-7 in a concentration-depend ent manner. At concentrations of 0.05 - 5 mg . L-1, the inhibition rat es were 24 -96%. These results suggested that GP-7 was an immunosuppre ssive agent.