Immunological studies of induced tumors of the rat submandibular gland.

The antigenic activity of rat submandibular gland carcinoma induced by 9,10 dimethyl-1,2 benzanthracene (DMBA) has been evaluated using rabbit antisera to normal submandibular gland extract and to extracts of the induced tumors. Extracts of all tumors and premalignant lesions show reduction in the concentration of several of the intrinsic antigens of the normal submandibular gland when they were evaluated by immunodiffusion and immunoelectrophoresis. Although all the induced tumors, including those used for antisera preparation, are well-differentiated epidermoid carcinoma, a considerable variation is present in the antigenic pattern of each tumor. When antisera to several tumors, absorbed with rat serum and kidney extract, were used in studying extracts of all induced tumors, antigenic bands were observed. The number of these bands varies from three to five. All the induced carcinomas share the presence of two of these bands in the alpha and beta-globulin region, the remaining bands differ from one tumor to another.