ABO blood group antigens on spermatozoa have been investigated using the agglutination inhibition technique. Antigens were not detected on spermatozoa from non-secretors, though they were detected on spermatozoa from secretors. Further, it has been demonstrated that spermatozoa will adsorb ABO antigens from aqueous solutions. The inhibition titres of seminal plasma and of spermatozoa from secretors were shown to be correlated.
It is concluded that ABO antigens are found only on seminal spermatozoa from secretors and that these are adsorbed from the seminal plasma.