Cookies on this website

We use cookies to ensure that we give you the best experience on our website. If you click 'Accept all cookies' we'll assume that you are happy to receive all cookies and you won't see this message again. If you click 'Reject all non-essential cookies' only necessary cookies providing core functionality such as security, network management, and accessibility will be enabled. Click 'Find out more' for information on how to change your cookie settings.

Beta-microseminoprotein (MSP) is one of the most abundant proteins secreted by the prostate gland. Because MSP is also synthesized in nonreproductive organs, the establishment of a solid relationship between the levels of MSP in serum and semen is crucial for future studies connecting MSP with aging or diseases of the prostate gland. We developed a specific, competitive, europium-based immunoassay to measure MSP in serum and seminal plasma. We also produced recombinant MSP in insect cells using baculo virus and purified it to homogeneity by a novel approach with ethanol extraction and gel filtration. The median values of MSP in 205 young men were 12 microg/L (2.5-97.5 percentile, 4.9-26 microg/L) in serum and 0.53 g/L (2.5-97.5 percentile, 0.13-2.0 g/L) or 1.8 mg (2.5-97.5 percentile, 0.32-6.6 mg) in seminal plasma. MSP in serum showed significant correlation to MSP in seminal plasma (r = .50, P < .001). Significant correlations were also found in seminal plasma between MSP and prostate-specific antigen (PSA) (r = .65, P < .001) and between MSP and Zn(2+) (r = .54, P < .001). The yield of recombinant MSP in culture medium was 35 mg/L or higher, and recovery following ethanol extraction was 80%-90%. MSP in serum reflects the prostate secretion of MSP, and correlations were also found in seminal plasma between MSP and PSA and Zn(2+). This suggests that MSP in serum can be used as a marker of prostate secretion, despite the contribution from extra prostatic tissues.

Original publication




Journal article


J Androl

Publication Date





330 - 337


Humans, Immunoassay, Male, Prostate-Specific Antigen, Prostatic Secretory Proteins, Recombinant Proteins, Semen, Zinc