rostate specific antigen（psA） was purified from the crude tissue extract of fresh humanprostatic tissue by CM-Sephadex-C

50

Sephadex-C

100

and DEAE-Sephadex-A

50

chromatogra-phy

SDS-PAGE showed tnat it had a molecular weight of 34KD Polyclonal antibody（PcAb） was ohained from rabbits immunized with PSA。 The PcAb wasasbsorbed with normal female serum（NFS）

precipitated with ammoniuin sulfate and then fol-lowed by DEAE 32 chromatography

The immunoblotting test indicated that it is specific forPSA 34.The immumohistochemical examination showed that the PcAh could stain the prostatictissues（normal

benign hypertrophic and、malignant）

but not the other human tissues

Two-Site sandwish enzvme-linked immunosorbent assay（ELISA）indicated that the mean content ofserum PSA in carcinoma of the prostate was significantly higher than that in the normal males.