Colorectal carcinoma-specific antigen: detection by means of monoclonal antibodies.

Fusion of P3 X 63 Ag8 mouse myeloma cells with splenocytes obtained from mice immunized with cells derived from human colorectal carcinomas resulted in the production of antibody-secreting hybridomas. Two hybridomas (1083-17 and 1116-56) and their clones secreted antibodies binding specifically to human colorectal carcinoma cells either grown in culture or obtained from patients, but did not bind to normal colonic mucosa or other normal and malignant human cells. The binding specificity was consistent in three assays: radioimmunoassay, mixed hemadsorption, and immunofluorescence. Adsorption of these antibodies to colorectal carcinoma cell lines totally eliminated their specific binding.