Development of rapid immuno-diagnostic test for the early detection of tuberculosis

Aims and objective To develop novel immunodiagnostic test for tuberculosis. Methods The selected novel proteins named as Rv2145c (SS1), Rv1437 (SS2), Rv1827 (SS3), and Rv2970c (SS4) were cloned, expressed and purified under specific conditions. Additionally, monoclonal antibodies (mAbs) were developed using these recombinant antigens via hybridoma technology. Hybridoma clones were screened and positive clones were selected for further experiment. The mAbs were purified from cell culture supernatant using protein A/G column chromatography. The diagnostic potential of these recombinant antigens and mAbs were investigated using a well characterized cohort of tuberculosis patients (Pulmonary-TB, Extra-pulmonary, MDR-TB) and healthy subjects sera using ELISA. Monoclonal antibodies (mAbs) raised against these antigens were used to detect the mycobacterial antigens. Result The selected recombinant antigens showed superior activity in the developed TB detection test. The observed sensitivity was 98.6% (SS4), 97.9% (SS1), 97.1% (SS3) and 92.7% (SS2), whereas specificity was 100% (SS1), 98.2% (SS4), 93.6% (SS3) and 87.5% (SS2). The purified mAbs also demonstrated good activity in the diagnosis of TB. Conclusion The novel recombinant antigens and mAbs generated against these antigen showed very good activity for the immunodiagnosis of TB. The combination of these recombinant antigens and mAbs could be used as novel biomarker for detection of active TB directly from patient sera.