MONOCLONAL-ANTIBODIES TO SQUAMOUS-CELL CA RCINOMAS OF THE UPPER AERODIGESTIVE TRACT

Background: Squamous cell carcinoma is the most common cancer of the h ead and neck. The application of monoclonal hybridoma technology to th e identification and characterization of molecules preferentially expr essed in carcinoma cells may provide potentionally important diagnosti c and therapeutic tools. Methods: After immunization of mice with viab le squamous cell carcinoma cells derived from human tumors of the uppe r aerodigestive tract hybridomas were selectively grown for production of monoclonal antibodies. Monoclonal antibodies produced by 690 hybri doma clones were tested on immunoreactions with frozen sections of hum an squamous cell carcinoma and reactive tonsils. Results: Immunohistoc hemical trials showed that monoclonal antibodies produced by hybridoma clone K-640 are strongly accumulated at the plasma membrane whereas n o immunoreaction in squamous epithelium of the tonsil could be detecte d. By means of ELISA it could be shown that these antibodies belong to the class of IgM. Immunoblotting revealed that the antibodies recogni ze antigenes with approximate molecular weights of 52 and 54 kD. Concl usions: The experiments suggest that the hybridoma clone K-640 produce s antibodies which bind to the plasmamembrane of the tumor cells. Furt her recloning steps of this hybridoma clone could possibly enhance the specificity of these antibodies for squamous cell carcinoma.