Beta-microseminoprotein (MSP) is a predominant protein of human seminal plasma and originates from prostate secretions. We have established the presence of its mRNA transcript and protein (W.blot or MS) not only in boar prostate but also in other reproductive organ tissues.
MSP has been localized on epididymal spermatozoa in the acrosomal region, on the flagellum of ejaculated spermatozoa and in the epithelial tissue of the prostate, epididymis, seminal vesicles and Cowper's glands.