Serodiagnostic Efficacy of Mycobacterium tuberculosis 30/32-kDa Mycolyl Transferase Complex, ESAT-6, and CFP-10 in Patients with Active Tuberculosis

• DOI: 10.1007/s00005-009-0055-4
• Publication Date: 2010-01-04T10:27:26Z
• Authors: Gavish Kumar; Pradeep Kumar Dagur; Prashant Kumar Singh; Hari Shankar; Virendra S. Yadav; Vishwa M. Katoch; Bharat Bajaj; Rajesh Gupta; Utpal Sengupta; Beenu Joshi
• Keywords: Adult; Male; 0301 basic medicine; Antigens, Bacterial; Adolescent; Immunology; Enzyme-Linked Immunosorbent Assay; Mycobacterium tuberculosis; Middle Aged; Sensitivity and Specificity; 3. Good health; 03 medical and health sciences; Bacterial Proteins; Immunology and Allergy; Feasibility Studies; Humans; Tuberculosis; Original Article; Female; Acyltransferases; Aged

Elimination of tuberculosis (TB) largely depends upon definitive rapid diagnosis and treatment. Widely used diagnostic tests do not qualify for use in a developing country due to lack of either desired accuracy or their cost. In the present study an enzyme-linked immunosorbent assay was used to evaluate the diagnostic potential of an immuno-dominant 30/32-kDa mycolyl transferase complex (Ag85 complex) and Mycobacterium tuberculosis-specific proteins (ESAT-6 and CFP-10) of the RD1 region. Higher sensitivity (84.1%) with Ag85 complex was observed compared with ESAT-6 (64.9%) and CFP-10 (66%), with almost similar specificity (Ag85: 85.2%, ESAT-6: 88.9%, CFP-10: 85.2%), whereas the individual components of Ag85 complex, i.e. Ag85A, Ag85B, and Ag85C, showed sensitivities of 44.6, 34, and 80.9% and specificities of 55.6, 74.1, and 40.7% respectively. A cocktail of Ag85 complex, ESAT-6, CFP-10, Ag85A, Ag85B, and Ag85C antigens also could not help in increasing either sensitivity (51.1%) or specificity (85.2%). Furthermore, immunoblot analysis using clinical isolates as well as a standard strain (H37Rv) of M. tuberculosis also showed strong reactivity of sera from TB patients to Ag85 complex and, to a lesser extent, also to ESAT-6. To conclude, use of Ag85 complex along with ESAT-6 and CFP-10 seems to be promising in minimizing the heterogeneous sero-responses of adult TB cases.