Human monoclonal antibody constructed by lymphocytes from pancreatic cancer patients

The lymphocytes from pancreatic cancer patients were fused with human lymphoblastoid cell line H0323 and three hundred and twenty eight human hybridomas were constructed. Among them, human monoclonal antibody OC2D (IgM) reacted with two of seven pancreatic cancer cell lines and two of four colon cancer cell lines and one hepatocellular cancer cell line, but not with four normal cell lines. OC2D reacted rather specifically with malignant tissues such as pancreatic cancer, colon cancer and gastric cancer by immunoperoxidase staining. Antigen recognized by OC2D appeared to be non-secreting and was mainly in cell surface. Various chemical studies showed that its epitope was a carbohydrate structure which did not contain sialic acid. These results suggested that human monoclonal antibody OC2D was useful for an imaging and targeting therapy.