Production and characterization of monoclonal antibodies against tissue specific epitopes on ABO blood group substances in saliva.

Mouse monoclonal antibodies (P4-2F, P4-5C) against ABO blood group substances in saliva were produced by immunization with ABO blood group active-glycoprotein after ethanol precipitation from heated saliva. These antibodies bound to saliva, irrespective of the ABO blood group and secretor status. Saliva diluted at least 3.2 x 10(4)-fold could be detected by ELISA using these antibodies. Tissue and species specificity of the antibodies was tested by ELISA and counterimmunoelectrophoresis and showed that the antibodies were specific for human saliva. By immunoblotting of the deglycosylated ABO blood group substances it was evident that the epitopes for the antibodies were localized on the core protein of blood group substances in saliva. These antibodies could be extremely suitable reagents for the identification of saliva in medico-legal examinations. Furthermore, they may be used as capture antibodies in sandwich methods for ABO blood grouping of saliva from mixtures of body fluids.