Monoclonal antibodies recognizing normal and neoplastic human adrenal cortex

Abstract

Four monoclonal antibodies (MAb) were generated by immunization of mice with dispersed cells from normal human adrenal gland (Na) and adrenocortical adenoma causing cortisol excess (Ac). Immunohistochemically reacted cryosections revealed differential labeling of the normal cortical parenchyma, and immunofluorescence on dispersed cells displayed that Ac5 alone labeled the cell surface. Immunoprecipitation demonstrated that the antibodies recognized apparently different structures of 51-88 kDa. Immunohistochemical examination of several normal human tissues substantiated restricted reactivity, especially for the Na2 and Na7 antibodies, and that the adrenal medulla was not stained by any of the antibodies. The antibodies recognized the vast majority of the parenchymal cells of cortical adenomas (n = 21). Each antibody also reacted with all adrenocortical carcinomas (n = 17), and the staining generally was most intense and extensive with Na7. Analysis of other pathological human tissues revealed highly restricted reactivity for the Na2 antibody. Na2 and Na5 failed to stain 17 renal cell carcinomas. None of the antibodies recognized pheochromocytomas. These antibodies may lead to improved histological recognition and characterization of human adrenal lesions.