Ultrastructural localizations of beta-microseminoprotein, a prostate-specific antigen, in human prostate and sperm:...

Immunohistochemical localizations of beta-microseminoprotein and gamma-seminoprotein, which are prostate-specific antigens, were examined by light and electron microscopy with peroxidase-labeled antibody. In normal, hypertrophic, and neoplastic prostate glands, beta-microseminoprotein was found in glandular epithelium but not in stroma cells. beta-Microseminoprotein may be as useful as gamma-seminoprotein in the pathologic examination of prostatic diseases, especially in histogenic classification of tumors or metastatic tumors. In an immunoelectron microscopic study, the primary localizations of beta-microseminoprotein and gamma-seminoprotein in the cell were demonstrated to be secretory granule and lysosome, respectively, suggesting that beta-microseminoprotein is a secretory protein. Weak distributions of beta-microseminoprotein and gamma-seminoprotein were observed in rough endoplasmic reticulum and Golgi apparatus. In spermatozoa, beta-microseminprotein was found attached to the cell membrane of the head but not in the tail, and gamma-seminoprotein was not found at all.