Human-human hybridomas generated with lymphocytes from patients with colorectal cancer.

Human-human hybridoma technology was used to produce human monoclonal antibodies with reactivity to colorectal cancer antigens. Two different B-lymphoma cell lines were fused with lymphocytes obtained from mesenteric lymph nodes from colorectal cancer patients. The fusion frequency was 11% with LICR-LON-HMy-2. Out of 294 growing hybridomas 26 secreted antibodies reacting with epitopes on cultured colon adenocarcinoma cells. Only one (D4213) was established and has now been in culture for 1.5 years. D4213 antibody shows a strong reaction with colon cancer tissue compared with normal colon epithelium. Using W1-L2-729-HF2 the fusion frequency was about 50%. Of 2,487 hybridomas 499 produced immunoglobulin and 44 of these reacted with colon cancer tissues or cultured cancer cells. One of the established hybridomas produces antibody reacting with cancer cell membrane antigens, and on immunoblotting a number of components were stained. The antibody from the other hybridomas reacts with cytoplasmatic antigens, and only one of these showed reactivity in immunoblotting where it bound to a component with Mr of about 60K.