Expression and characterization of a chimeric bifunctional antibody with therapeutic applications

A simple method is described for the generation of a biologically produced mouse/human chimeric hetero-bifunctional antibody that has dual specificity for human carcinoembryonic Ag and metal chelate haptens. Two large compound chimeric vectors each containing the genetic information to produce a single antibody specificity were sequentially electroporated into the murine nonsecreting hybridoma SP2/0. This led to the isolation of a clone expressing high levels of total IgG (up to 25 micrograms/ml/10(6) cells), 10 to 20% of which showed simultaneous reactivity with both Ag. Binding studies showed that the immunoreactivities and affinity constants for the individual arms of the bifunctional antibody were equivalent to those seen with the parental antibodies.