Production of monoclonal antibodies against the non-specific cross-reacting antigen (NCA).

Hybridomas were prepared by fusion of mouse spleen cells immunized with purified NCA (non-specific cross-reacting antigen) with cells of myeloma SP2/0. After cloning, several clones were obtained which produced antibodies specific for NCA, i.e., not reacting with CEA. All antibodies were IgG1 Kappa. Their affinity constants were higher at 4 degrees C than at 37 degrees C. They revealed the existence of at least two epitopes on the specific moiety of NCA.