Antibody based assays to detect Mycobacterium leprae infection: Towards a new horizon

In several countries including India, leprosy, still, seems to remain as a special health problem. Early detection of Mycobacterium leprae infection is considered as an important component of strategies aiming at reducing transmission of infection, but currently available diagnostic tools often lack sufficient sensitivity and specificity to reach this goal. However, the major constraint for immunodiagnosis of leprosy is the rare availability of specific and potential M. leprae antigens. Though, a large amount of M. leprae can be harvested from infected armadillos maintained under laboratory conditions, this preparation is crude and contains armadillo proteins with possible undesirable effects. Recombinant protein technology seems to be a promising solution to overcome these obstacles. In the present write-up, descriptions of the potentials and future directions for various promising recombinant antigens have been discussed briefly. Recent comparative genomics has revealed the presence of more than 100 M. leprae genes with no homologue in M. tuberculosis. This, in combination with proteomics might provide avenues to recognize some novel antigens and thereby to genetically engineer several more antigens for their use in serodiagnosis of leprosy patients.