Monoclonal antibodies against beta-antigen of Mycobacterium tuberculosis and their interspecies reactivities.

Beta-antigen is one of the major proteins of Mycobacterium tuberculosis. We purified this antigen from the unheated culture filtrate of Mycobacterium tuberculosis Aoyama B and obtained nine monoclonal antibodies against the beta-antigen. Nine monoclonal antibodies were divided into two groups according to their patterns on Western blotting. The result indicated the existence of two or more determinant groups against these monoclonal antibodies on the beta-antigen molecule. The interspecies reactivity of monoclonal antibodies among twenty-one species of Mycobacteria was also examined by dot blotting analysis. Two monoclonal antibodies, designated 4G5E10 and 5F3F2, showed a specificity restricted to the Mycobacterium tuberculosis complex, could be used for serodiagnosis of Mycobacterium tuberculosis infection.