ACID-HYDROLYSIS OF MONOCLONAL-ANTIBODIES

For analysis of monoclonal antibodies using polyacrylamide gel electro phoresis, two hydrolytic fragments derived from the heavy chain of mou se IgG1 were produced during incubation of the antibodies in Laemmli r educing sample buffer at 100 degrees C for 5 min. The cleavage sites w ere identified by amino terminal sequencing. Results indicate that the final pH of the mixture is critical for the production of the fragmen ts which are generated when the pH is approximately 6.0. At pH 8.0, no fragments are detected. The relevance of this finding to those workin g with monoclonal antibodies is discussed.