Characterization of monoclonal antibodies to human salivary (glyco) proteins. Cellular localization of mucin, cystatin-like 14 kD protein and 20 kD glycoprotein in the human submandibular gland.

Using the hybridoma technique, monoclonal antibodies (Mabs) have been produced against three different types of human salivary proteins: high molecular weight mucin, a 20 kD glycoprotein and a 14 kD protein, identified as a member of the cystatin family. The Mabs appeared to be highly specific to their antigen in Elisa and immunoblotting tests. The Mabs were of the IgG-1 (against 20 kD glycoprotein) and IgM (against 14 kD protein and mucin) type. For the 14 kD protein and the 20 kD glycoprotein it was demonstrated that they are present mainly in submandibular-sublingual saliva. None of the antigens studied could be localized distinctly in the human parotid gland. In the submandibular gland, the three proteins have a different pattern of localization. The mucins have been detected particularly in the apical part of the mucous acinar cells, the 20 kD glycoprotein mainly in the serous acinar cells and the 14 kD protein in both serous acinar cells and striated duct cells.