We examined a large number of individual human and animal saliva samples fo
r the reactivity with 1CF11, a mouse monoclonal antibody previously produce
d for the characterization of human milk mucin and apparently recognizing a
certain carbohydrate antigenic structure shared by various human glycoprot
eins in secretions. The results obtained here confirm the unique occurrence
of 1CF11 epitope in each and every saliva sample from humans and Old world
monkeys as well, though a Fast variety was observed among individual saliv
a samples in the immunological reactivity with 1CF11.