Antigen-specific immunodepression induced by doxorubicin-BSA conjugate in mice

Injection into mice of the anthracycline cytotoxic derivative Doxorubicin (DXR) covalently bound to bovine serum albumin (BSA) was associated with antigen-specific depression of the primary (but not of the secondary) antibody reaction to the carrier, whereas DXR and BSA injected in the form of a mixture caused no such effect. Tetanus toxoid completely prevented the carrier-specific inhibiting effect when administered at the same time as, but not three days before or after, injection of the DXR-BSA conjugate. Possible mechanisms of the antigen-specific immunodepression and its prevention by unrelated antigen are discussed.