Serological and immunohistochemical detection of a gastrointestinal cancer-associated asialoglycoprotein antigen of human with a murine monoclonal antibody.

A murine monoclonal antibody (mAb), NCC-AS 13 (IgM, kappa), was produced after immunization with ascites from a gastric cancer patient. In a sandwich enzyme immunoassay, NCC-AS 13 reacted with the sera from 32% of 58 gastric cancer patients, 44% of 9 hepatocellular cancer patients and 33% of 6 colorectal cancer patients. Immunohistological analysis showed NCC-AS 13 to react with approximately 90% of 51 gastric carcinomas, 12 out of 12 colon carcinomas and 3 out of 4 lung carcinomas. The NCC-AS 13 defined antigen was determined to be a carbohydrate without terminal sialic acid on macromolecular glycoproteins. This mAb NCC-AS 13, detecting a novel antigen associated with gastrointestinal cancers, may have potential uses for tumor immunoscintigraphy and for the therapy of gastric cancer patients.