The ultrastructural localization of prostatic specific antigen and prostatic acid phosphatase in hyperplastic and neoplastic human prostates.

A low temperature embedding, protein A-gold technique was used to localize prostatic specific antigen and prostatic acid phosphatase at the ultrastructural level in hyperplastic and neoplastic human prostates. Prostatic specific antigen immunoreactivity was localized over the endoplasmic reticulum, cytoplasmic vesicles and vacuoles, and within the lumina of prostatic glands. In contrast, prostatic acid phosphatase immunoreactivity was localized to lysosomal granules. The pattern of labelling was similar in both hyperplastic glands and adenocarcinomas. This is the first localization of prostatic specific antigen at the ultrastructural level. The localization of prostatic acid phosphatase by an immunochemical technique confirms and expands previous histochemical observations.