Human melanoma and leukemia associated antigens difined by nonhuman primate antisera

The rationale of our approach to the detection and characterization of human leukemia and melanoma associated membrane antigens is to take advantage of the unique immunological recognition perspective of simians to huamn antigens. There are enough antigenic similarities between man and nonhuman primates to blunt the immune response of apes and monkeys to huamn species-specific antigens. Their response to allogeneic normal human antigens such as HL-A can now be managed by in vitro absorption procedures. High titered antibodies specific for tumor associated membrane antigens have not been well documented in serological studies with patients' sera. Immunization of nonhuman primates utilizes a fully immunocompetent recipient who has no tumor and is not on chemotherapy. The immunization can utilize adjuvants and other regimens that morally and ethically cannot be easily used for human allogeneic immunization. The simian antisera that are shown to be specific for human tumor membrane antigens can then be utilized for studies on the isolation and characterization of the antigens. Similar studies with HL-A antigens indicated that the solubilized partially purified antigens can then be used to elicit high titered antibodies in other simians. These latter antisera can then be used for more sensitive assays and studies on the association of the antigen(s) with the cell membrane. Although the work summarized here covers leukemia and melamona antigens, it is felt the approach will serve as a model for the detection by simian antisera of tumor-specific membrane antigens of cancer cells from patients with various types of solid tumors.