Characterization of a monoclonal antibody specific for prostatic secretory protein of 94 amino acids (PSP94) and development of a two-site binding enzyme immunoassay for PSP94.

Purified prostatic secretory protein of 94 amino acids (PSP94) was used to generate polyclonal rabbit anti-PSP94 IgG and a murine monoclonal antibody 6B6 (mAB6B6). Both antibodies were highly specific for PSP94 by immunoblotting. Immunohistochemical studies demonstrated the specificity of mAB6B6 for human prostatic epithelial tissue. A two-site binding enzyme immunoassay for the detection of PSP94 was developed using a combination of the antibodies. The sandwich-ELISA yielded satisfactory results when mAB6B6 complexed to peroxidase conjugated goat anti-mouse-IgG (Fc) was incubated simultaneously with the sample. The assay has a dynamic range of 2-30 micrograms/l. This immunoassay was employed to measure PSP94 in male human sera (8 +/- 4 micrograms/l), female human sera (5.7 +/- 3.4 micrograms/l), follicular fluid (3.9 +/- 2.9 micrograms/l) and human seminal plasma (1.02 +/- 0.8 g/l).