Expression of vasoactive intestinal polypeptide and amylase in a human parotid gland adenocarcinoma cell line in culture.

A neoplastic epithelial cell line initially established in culture from a human parotid gland adenocarcinoma grown in athymic nude mice with a BALB/c genetic background, which has an ultrastructure similar to that of the intercalated duct cell of the salivary glands, was examined for the expression of amylase and vasoactive intestinal polypeptide (VIP). The cultured cells were found by the peroxidase-antiperoxidase (PAP) method to express amylase and ultrastructurally to have secretory granules showing positive immunoreaction with anti-amylase serum. In addition, the cells were found to secrete amylase into the culture medium. The expression of VIP in the cultured cells was observed by the PAP method, immunofluorescent staining method, or immunoelectron microscopy. Moreover, the presence of the polypeptide reactive to antibodies directed against VIP in the cultured cells was confirmed by immunoblotting and radioimmunoassay. These findings indicate that the cells proliferating in culture express both amylase and VIP.