Abstract
Male human urethra] epithelium was treated for the immunohistochemical demonstration of secretory IgA in order to verify its own possible antimicrobial properties. An intense immunoreactivity for slgA in the entire cytoplasm and at the luminal surface of the apical epithelial cells was observed. The results suggest that slgA play a prominent role in the local defense mechanisms of the urethra. Such mucosal defense mechanisms may be of significance in the defense of the urinary and genital tract against ascending infections.