Carbohydrate antigen 15-3 and mucinous carbohydrate antigen immunoreactivities in human seminal plasma

Carbohydrate antigen 15-3 (CA 15-3) and mucinous carbohydrate antigen (MCA) immunoreactivities were detected in human seminal plasma. Mean values for CA 15-3 (8.2 +/- 3.7 U/ml, range 2.6 - 18.4 U/ml) and MCA (13.8 +/- 8.2 U/ml, range 2.1-31.9 U/ml) in the seminal plasma were of the same magnitude as that found in serum. No correlation was obtained between seminal plasma, either CA 15-3 or MCA immunoreactivities, and volume of seminal plasma, sperm count or percent of motile spermatozoa. Seminal plasma CA 15-3 and MCA levels were significantly (p less than 0.001) correlated (r = 0.55). The nature and origin of CA 15-3 and MCA immunoreactivities in human plasma are unknown.