Immunotherapy of leprosy.

Immunotherapy aims to modify the defective cell-mediated immune response in a section of leprosy cases. This presentation reviews the various immunomodulators developed/ investigated for this purpose. Among the various mycobacterial agents, BCG, BCG + M.leprae, Mycobacterium w, ICRC bacillus and M.vaccae have been tried in leprosy patients and varying degree of beneficial effects on bacterial killing and clearance have been observed. Studies carried out at CJIL, Agra and elsewhere suggest an important role for these mycobacteria as immunotherapeutic agents. Other mycobacteria-M.habana, M.phlei, M.gordonae-have also been reported to be promising experimentally. In addition, various drugs such as levamisole, zinc and RACA 854 have been observed to have immunomodulatory role in leprosy cases. Other promising immunomudlators include transfer factor, interferon gamma, interleukin 2 and acetoacetylated M.leprae. The progress achieved shows that immunotherapy may be considered as adjunct to chemotherapy to enhance bacterial killing as well as bacterial clearance and thus may be recommended to shorten the treatment period, specially in bacilliferous leprosy cases.