[Use of monoclonal antibodies in immunoenzyme analysis for demonstrating antigenic monovalency]

To prove the monovalence of the antigen a method has been developed consisting of ELISA with the use of monoclonal antibodies in combination with the antibody neutralization test. Yersinia pestis capsular antigen was disintegrated by heating at 100 degrees C for a short time and subsequently passed through a column packed with Sephadex G-50. The portions of the eluate, showing high activity in the antibody neutralization test and low activity in ELISA (the double antibody sandwich scheme), contained mainly the monovalent antigen. This antigen was replaced by the polyvalent antigen from the antibody complex, but if such complex had been previously fixed by treatment with glutaraldehyde, no replacement of the monovalent antigen by the polyvalent one occurred.