[Gamma interferon-like immunoreactivity in adrenal gland and cortical tumor]

Interferon-gamma (IFN-gamma) has many important immunoregulatory functions. It has previously been presumed to be produced by activated lymphoid cells alone. Recently, IFN-gamma like immunoreactivity has been described in certain parts of the nervous system and the skeletal or cardiac muscle system in the rat. We wanted to know whether this molecule could be expressed in the human adrenal gland and cortical tumors. Adrenal tissue samples were taken adjacent to 14 tumor cases, from 17 adrenal cortical adenomas, and 7 cortical carcinoma cases. Deparaffinized 5 microns sections were stained with IFN-gamma monoclonal DB-1 antiserum. The avidin-biotin complex method was used. IFN-gamma appeared in the cytoplasm of tumor cells in 7/7 cases of adrenal cortical carcinoma, 8/17 cases of cortical adenoma and endothelium in 2/7 cases of adrenal cortical carcinoma and 5/17 cases of cortical adenoma. No immunoreactivity was observed in tumor adjacent adrenal gland. Therefore, IFN-gamma is associated with cell differentiation, the higher the immunoreactivity, the lower the differentiation. The capillary endothelium in adrenal cortical tumor tissue may possess receptor for IFN-gamma or can produce IFN-gamma.