Immunohistological approaches to human prostatic epithelial cells

Specific anti‐acid phosphatase antisera were prepared by the use of purified prostatic acid phosphatase (PAP) from prostatic tissue and lysosomal acid phosphatase (L‐AcP) from diploid fibroblast (WI‐38) as antigen. Since the antigenic difference between the PAP and L‐AcP was established, distribution of these enzymes among various tissues and tissue culture cells was investigated by the indirect immunofluorescence method and the unlabeled antibody method [14]. The L‐AcP has been detected as granules localized in a perinuclear portion of all of the epithelial cells, fibroblasts, and peripheral blood cells except erythrocytes. Presence of the PAP was limited to the prostatic epithelial cells. It is also noted that the biosynthesis of the PAP is strikingly diminished in the long‐term culture of prostatic epithelial cells. However, because of the antigenic difference between the PAP and L‐AcP, and because of the high concentration of PAP in the cytoplasm of prostatic epithelial cells, it is feasible to apply the anti‐PAP immunofluorescence method to the identification of metastatic prostatic carcinoma cells in the biopsy materials.