The isolation of a possible antagglutinin from human semen

A substance, proteinaceous in nature, with an anti-agglutinic action on clumped sperm has been extracted from human semen. It appears to exist in two forms: an active reduced form and an inactive oxidised form. The protein was extracted from oxidised seminal plasma by salting with saturated ammonium sulphate. The extract was purified by preferential adsorption on a calcium carbonate column, the eluate being collected as fractions. The antagglutinin gave an extinction curve, as determined by ultraviolet spectrophotometry, similar to that as reported for the bull. Extraction recoveries, from semen stored frozen at different temperatures, indicate that the substance is possibly enzyme labile. An effect of the antagglutinin on clumped human sperm is illustrated.