The Detection of Prostatic Acid Phosphatase by Antibody Reactions in Gel Diffusion

Summary Prostatic acid phosphatase was demonstrated in electrophoretic patterns of prostatic fluid in the region corresponding to the serum α2- and β-globulins. In gel diffusion precipitation, this enzymatic activity was localized in two distinct bands of dense brown, speckled appearance. The titration end point of the major band varied with the sample of prostatic fluid; some were as high as 1:16000. In immunoelectrophoresis, the activity was again localized in two of the precipitin bands that were formed with the homologous antiserum. These bands were clearly of different electrophoretic mobility, suggesting that there are two different molecules having similar enzymatic properties. A number of organ extracts were tested for this phosphatase activity, namely, seminal vesicle, kidney, testicle, liver, lung and prostate gland. All of these were negative except for prostate extract, which did show one line of reaction. Normal serum was also negative. Serum from patients with carcinoma of the prostate were also positive, but only in some of the experiments. This is being further studied.