immunotoxin

An immunotoxin is a chemical that can cause immune system malfunction with exposure. When the immune system function is suppressed (immunosuppression) there is an increased susceptibility to infectious diseases and cancers. Polychlorinated-biphenyls (PCB), asbestos and herbicide DDT are known immunosuppressants. Immunotoxins can also cause autoimmune disease, where an overactive immune system attacks the bodies cells.
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An antibody linked to a toxic substance. Some immunotoxins can bind to cancer cells and kill them.

A combination of a monoclonal antibody and a toxic (e.g., anticancer) substance. Because it responds only to specific antigens, the MoAb component limits the toxic effects of the immunotoxin to target (e.g., tumor) cells.