Identification of melanoma-associated antigens using fixed tissue screening of antibodies.

Early culture supernatants from hybridomas that were obtained through fusions of mouse myeloma cells with lymphocytes of melanoma-immunized mice were screened for their reactivity with a paraffin-embedded cell block of a melanoma cell line, using a biotin:avidin immunoperoxidase procedure. Eleven monoclonal antibodies were derived that define several new melanoma-associated antigens. The antigens include a neutral glycolipid, gangliosides, membrane-associated proteins, cytosolic proteins, and strongly secreted proteins. These antibodies, which detect antigens that withstand tissue fixation and embedding procedures, were tested for reactivity in fixed cell lines, as well as in melanoma biopsies. These antibodies may provide powerful tools in diagnostic studies of human malignant melanoma biopsy material.