Results of the third immunology of leprosy/immunology of tuberculosis antimycobacterial monoclonal antibody workshop.

An international workshop was sponsored by the World Health organization to screen new antimycobacterial monoclonal antibodies and to identify antibodies which could be recommended as standard reagents giving consistent results under differing assay conditions. Fifty-eight antibodies were submitted to the workshop by eight independent laboratories. Nineteen of the antibodies recognized antigens distinct from those identified in earlier workshops, defining at least 10 new protein antigens. Monoclonal antibodies characterized in the workshop provide a set of convenient reagents for further characterization of mycobacterial antigens.

A rapid latex agglutination test for detection of antibodies in tuberculosis and Hansen's disease.

Antigens of Mycobacterium w, a saprophytic fast growing organism having antigenic epitopes cross-reactive with Mycobacterium leprae and Mycobacterium tuberculosis, were coated on to latex beads (0.33 micron Zn size), and the reactivity tested with sera of tuberculosis and Hansen's disease (HD) patients. Seventy nine percent of lepromatous leprosy (LL) and eighty five percent of pulmonary tuberculosis (TB) patients sera showed an agglutination reaction easily read by naked eye. Specificity of the test was further checked by testing sera of non-mycobacterial infection cases and all of them were found negative. Among apparently healthy controls, 4.3% were found positive from non-endemic and 8.8% from endemic area. The sensitivity of the assay is further enhanced from 78.7% to 90.4% and 85.7% to 91.6% in both LL HD and pulmonary tuberculosis respectively, by using immune complexes extracted from the patients sera. Potential of these antigen coated beads to detect the two major human mycobacterial disease, LL HD and pulmonary TB was also put evidence in a double blind study on coded sera samples obtained from various hospitals in India. The antigen coated beads are stable for upto 6 months at 4 degrees C. The latex slide agglutination test reported here, is simple, rapid, easy to perform and can be used even in rural areas of developing countries.

Immuno-blot analysis of antigens of Mycobacterium w: a candidate anti-leprosy vaccine using monoclonal antibodies and patient sera.

The presence of determinants immunologically cross-reactive with M. leprae and M. tuberculosis in Mycobacterium w (M. w) has been revealed by immunoblotting using cross-reactive and specific monoclonal antibodies (Moabs) to M. leprae and M. tuberculosis. Three of the seven M. leprae and one of the two M. tuberculosis "specific" Moabs showed reactivity with M. w antigens. Reactions were also manifest with cross-reactive Moabs. One out of the three Moabs raised to M. leprae and three of six to M. tuberculosis demonstrated reactivity with M. w antigens. Extensive reactivity of M. w antigens was also observed with patient sera; sera from leprosy patients reacted prominently with M. w antigens at 14-17 KDa and sera of active tuberculosis patients exhibited reactivity at 21 KDa antigens of M. w. Four out of 30 healthy individuals living in an endemic area showed reactivity with M. w antigens.