Genetic engineering of immunotoxins.

Immunotoxins, composed of both targeting mechanisms and toxins, hold great promise for the treatment of some cancers and other pathological conditions. Research and manufacture of these drugs use various techniques of molecular biology, some of which are described in this article. A considerable amount of research has focused on ricin, a plant toxin, and its immunoconjugates. Areas currently under evaluation by our laboratory include structure-function studies based on mutational analysis, enhancement of intracellular trafficking, genetic fusion of the targeting and toxic moieties, and the expression of toxin in plant cell culture.