Circulating immune complexes (CIC's) are associated with disease progression in Tuberculosis (TB) though their role in pathogenesis is still unclear. Hence the present study was undertaken to identify proteins of diagnostic potential in tuberculosis by proteomic profiling of CIC's. Serum samples from tuberculosis patients (n=28), latent TB (n=10) and healthy (n=15) individuals were collected and CIC's levels were estimated by ELISA. CIC's were isolated by 7% Polyethylene Glycol precipitation and were subjected to proteomic analysis. Bioinformatic analysis and functional annotation of identified proteins was performed using Mascot search engine and PANTHER respectively. Identified protein was validated by ELISA. Statistical analysis was performed with SPSS version 16 and Graph pad prism 5. The mean CIC concentration in TB, latent TB and healthy individuals was found to be 38.23±11.45, 24.43±15.09, and 8.61±2.47µg/ml respectively. A total of 74, 48 and 60 proteins were identified in CIC's from of TB, latent TB and healthy individuals respectively. Among identified proteins the sensitivity, specificity, positive predictive value, negative predictive value and accuracy of C1qC to distinguishing TB patients from controls (with respect to both latent TB and healthy controls) was found to be 87.18%, 93.33%, 94.44%, 84.85% and 89.86% respectively. Our exploratory analysis suggests that immune-complex based assays might provide better alternate to invasive diagnostic techniques especially in diagnosis of extra pulmonary TB. However, further elaborate studies are required.
All Science Journal Classification (ASJC) codes
- Applied Microbiology and Biotechnology