A rapid method for comparing monoclonal antibodies by limited proteolysis and electrophoresis.

A rapid and sensitive method for comparing the primary structure of proteins has been adapted to the study of monoclonal antibodies. Samples were digested with alpha-chymotrypsin in the presence of sodium dodecyl sulfate after which peptide fragments were separated into distinctive banding patterns by polyacrylamide gel electrophoresis. This method could easily detect differences in the primary structure of antibodies with related as well as unrelated binding specificities. In addition, antibody molecules derived by somatic diversification from the same germ line gene segments could be distinguished from one another.