Thymodepressin—Unforeseen Immunosuppressor
Deigin VI, Vinogradova YE, Vinogradov DL, Krasilshchikova MS, Ivanov VT (2021). Molecules.
Summary
Part review, part new experiments on Thymodepressin, the D-amino-acid enantiomer of the Thymogen dipeptide, which the authors report has the opposite effect: it suppresses rather than stimulates immune responses. The historical section describes its discovery during structure-activity work on Thymogen. New experiments compared it with cyclosporin A in mice with mercury-induced autoimmunity, where Thymodepressin lowered anti-fibrillarin antibody titres in both preventive and therapeutic regimens while cyclosporin worked only preventively, and in a graft-versus-host model, where it suppressed splenomegaly more than cyclosporin. A mouse study by the compound's developers.