Immunoprecipitation of insulin receptors by antibodies against Class 1 antigens of the murine H-2 major histocompatibility complex.

Insulin receptors from C57BL/6J mouse (H-2b) liver membranes were specifically labeled with 125I-photo-reactive insulin by UV irradiation. Membranes were solubilized and the capacity of various antibodies reacting with the major histocompatibility complex to immunoprecipitate insulin receptors was tested. About 5% of the labeled receptors were immunoprecipitated by a conventional mouse antiserum against H-2b histocompatibility antigens and by a monoclonal antibody against Class 1 antigens of the H-2b haplotype (Kb and Db). No immunoprecipitation was obtained with a monoclonal antibody against Class 2 antigens of I-Ab or against Class 1 antigens of the H-2k haplotype. Insulin receptors can thus be specifically immunoprecipitated by antibodies against class I histocompatibility antigens.