[Isolation of type-A blood group active glycoproteins from salivas and their reaction with monoclonal antibodies].

We have previously examined several ABO blood grouping antibodies with whole saliva and observed that there were two types of antibodies. One group of antibodies reacted with both secretory and non-secretory saliva, and the other with only secretory saliva. In order to clarify the differences in reaction of the antibodies with saliva, we needed to analyze of antigens in secretory and non-secretory saliva. Therefore, we prepared blood group active glycoproteins from secretory and non-secretory saliva by affinity chromatography and gel filtration. The secretory saliva gave three active peaks, one large peak in the void volume and two small peaks in fractions of smaller molecular weights on Sepharose-CL6B after the affinity chromatography. From the non-secretory saliva, a single active peak in the void volume, which corresponded to the major peak in the secretory saliva, was found. Most blood group activities were found in those void volume fractions. Moreover, capillary electrophoresis showed that these blood group active glycoproteins were identical, and that there were immunological differences between secretory and non-secretory salivary blood group substances.