In addition to multidrug therapy, elimination of leprosy requires improved diagnostic methods. Using a comparative genomics approach, 17 potential protein antigens (MLP) that are restricted to Mycobacterium leprae, or of limited distribution, were produced and tested for antigen-specific immune responses on leprosy patients, healthy contacts of leprosy patients, and tuberculosis patients in Mali and Bangladesh, as well as on non-endemic controls. T-cell antigenicity of MLP was confirmed by IFN-γ production in whole-blood assays with the highest responses observed in paucibacillary leprosy patients and healthy contacts. Four MLP behaved well in both countries and induced significantly different responses between the study groups. Peptides carrying T cell epitopes from one of the antigens gave promising results in restimulation assays in mice and immune responses were not influenced by prior exposure to BCG or environmental mycobacteria. This study provides the immunological framework for the development of a specific, peptide-based immunodiagnostic test for leprosy.
Bibliographical noteFunding Information:
We thank all the patients and members of control groups for participating in this study and the staff of the various clinics for their support. This work was supported by the UNICEF/UNDP/World Bank/WHO Special Programme for Research and Training in Tropical Diseases (TDR grant number A20527), the Association Française Raoul Follereau, and the National Institutes of Health, National Institute of Allergy and Infectious Diseases (grants no. 1 RO1-AI47197-01A1, NO1-AI25469).
All Science Journal Classification (ASJC) codes
- Infectious Diseases