Serum miR-29a and miR- 361-5p as Biomarkers among Patients with Pulmonary Tuberculosis

Abstract

Tuberculosis remains a major global health problem. It causes ill-health among millions of people each year and ranks as the second leading cause of death from an infectious disease worldwide, after the HIV. Early diagnosis of TB infection is essential for the control of the spread of tuberculosis and for adequate antimicrobial therapy against mycobacterial infection. Nevertheless, TB can be a difficult disease to diagnose. Routine clinical methods for diagnosing TB, involving radiography, culture of sputum and the tuberculin skin test, have many shortcomings. Finding new biomarkers in tuberculosis is not only necessary for diagnosing patients with TB, but also for the staging or classification of TB, TB prognosis, and TB drug and vaccine trials. MiRNAs are small non-coding single-stranded RNAs, 19-25 nt in length, acting as negative regulators of gene expression at the post-transcriptional level. In this study, we aimed to detect expression of miRNA 29a and miRNA 361-5p in sera of patients with active pulmonary TB, attempting to evaluate their role as potential biomarkers for the diagnosis of pulmonary TB infection. This study was carried out on 20 patients with active pulmonary TB (Group I) selected from the chest hospital. Their mean age was 36.70± 11.49 years. They were 13 males and 7 females. Patients were diagnosed with active pulmonary TB before having anti-TB drugs or had taken anti-TB drugs for less than four weeks. They were diagnosed on the basis of positive results of sputum smear and/or TB culture, in combination with clinical symptoms and a chest X-ray examination.15 patients with pulmonary infection with microbial pathogens other than M. tuberculosis (Group II) selected from the chest department of Ain Shams University Hospital. Their mean age was 31.13± 9.88 years.They were 11 males and 4 females. 15 healthy age and sex matched subjects recruited as controls (Group III). Their mean age was 29± 4.75 years. They were 13 males and 2 females. Tuberculin test was performed to exclude latent TB infection from healthy controls.