Immunotoxins: A new approach to cancer therapy

This chapter presents evidence that conjugates of toxin and antigen can induce specific immunologic unresponsiveness. A potential problem in the repeated administration of immunotoxins in cancer patients is the generation of an antibody response to the injected immunotoxin. The induction of immunologic unresponsiveness to specific antigens would be useful not only in cancer patients that are to receive immunotoxins containing tumor-reactive antibody but also in treating autoimmune diseases. For example, in the case of an autoimmune disease in which the antigen has been identified, it may be possible to delete the B cells responsive to this autoantigen by injecting autoantigen-A chain. Immunotoxins represent a new approach to pharmacology. In considering the use of immunotoxins for treating human cancer, the tumor burden must be a major consideration—at least until the therapeutic index of immunotoxins can be significantly improved. Studies of the metabolic half-life and tissue distribution of immunotoxins are also of a preliminary nature.