Influence of the cysteine derivatives on the cell-mediated immunity.

The immunosuppressive action of N,N, S-trimethyl-cysteine, S-methyl-L-cysteine hydrazide hydrochloride and L-cysteine hydrazide on the course of post-adjuvant polyarthritis, graft-versus-host reaction, turpentine oedema and incorporation of 3H-thymidine into spontaneous or PHA stimulated lymphocyte cultures was examined. Inhibition of post-adjuvant polyarthritis and prolongation of skin allograft survival time were observed. L-cysteine hydrazide had shown the most inhibiting action. In vitro, S-methyl-L-cysteine hydrazide hydrochloride decreased and N,N, S-trimethyl-cysteine increased the incorporation of 3H-thymidine into the lymphocyte cultures stimulated by PHA. The obtained results were compared with the action of DL-cysteine hydrochloride.