Production and characterization of new murine monoclonal antibodies reactive to Mycobacterium tuberculosis.

Murine monoclonal antibodies were raised against Mycobacterium tuberculosis (H37Rv) employing conventional hybridoma procedure. The binding characteristics of the four selected monoclonal antibodies reactive to M. tuberculosis were assessed by enzyme-linked immunosorbent assay (ELISA) using sonic extracts. The immunofluorescence test (IFT) was done using intact M. tuberculosis, 16 other mycobacterial species, and 10 bacteria of other genera. Monoclonal antibody A30 reacted strongly to M. tuberculosis both in ELISA and IFT. Monoclonal antibody A25 showed restricted cross-reactivity with mycobacterial species whereas two other monoclonal antibodies B6 and H2 appeared broadly cross-reactive. In Western blot analysis, A30 reacted with the 30-kD protein antigen, A25 with the 18- and 28-kD protein bands, H2 with the 18-kD antigen alone, and B6 with three bands of 17-19, 22, and 28 kD of M. tuberculosis H37Rv. A30 exhibited high reactivity with virulent M. tuberculosis H37Rv and a clinical South Indian Strain and minimal reactivity with avirulent M. tuberculosis H37Ra strain.