Prospects for immunotoxin therapy in cancer.

Immunotoxins are formed by chemically linking antibodies to "toxic" polypeptides that inactivate protein synthesis. These hybrid protein molecules are guided to tumor cells by the antibody moiety, and once bound to the tumor cells, the toxic polypeptide moiety penetrates the cell membrane and enzymatically inactivates protein synthesis. A stepwise approach to identifying the potential clinical uses of immunotoxins in cancer therapy is examined in this chapter.