Identification of Point Mutations in Genes Coding for tum-Antigens. A Step Towards the Understanding of Mouse and Human Tumor-Specific Transplantation Antigens?

Abstract

Most experimental tumors induced with chemical carcinogens or UV radiation express individually specific transplantation antigens that elicit a T cell-mediated immune rejection in the syngeneic animals (Prehn and Main 1957; Klein et al. 1960; Kripke 1981; Uyttenhove et al. 1983). The characterization of these transplantation antigens has proved very difficult and several different approaches have been followed. One involves the search for specific antibodies to isolate the antigen by immunoprecipitation. Unfortunately, tumors seldom elicit antibodies directed against their specific transplantation antigens. One notable exception is UV-induced tumor 1591, and the molecules that were isolated with these antibodies proved to be modified H-2 class I molecules (Phillips et al. 1985; Linsk et al. 1986). Another approach involves the biochemical fractionation of membrane constituents and the assay of their ability to induce in vivo a specific immune protection against the tumor. It was applied to methylcholanthrene-induced sarcomas and a family of 96-kDa surface glyco-proteins was recently reported to induce a specific immunity (Srivastava et al. 1987). We have used yet another approach aimed at the direct isolation of genes coding for “tum^-” transplantation antigens, which are observed on mouse tumor cells treated with mutagens. We begin therefore with a brief description of this system.