Abstract

Background: MicroRNAs are small non-coding entities playing crucial role as post-transcriptional regulators during mycobacterial infection. Though various sputum microRNA expressions may have a role as potential biomarkers in diagnosing pulmonary tuberculosis (PTB), their correlation with a standard treatment regimen is yet to be ascertained.

Aims and Objectives: To correlate sputum microRNA-144 (miR-144) expression levels in PTB patients before and at the end of intensive phase of DOTS with treatment response.

Methods: A total of 46 patients were enrolled from a teaching institute in India, between February 2017 and February 2018. All had either sputum smear positive or negative PTB. Sputum samples were collected before the initiation of treatment and at the end of intensive phase as per Indian National guidelines. Twelve patients of Asthma or COPD, not in infective exacerbation, were recruited as controls. Quantitative real-time PCR (qRT-PCR) was performed to measure the miR-144 levels.

Results: Before treatment, miR-144 levels among PTB patients were significantly higher than that of the controls (p<0.05).In patients who had sputum conversion, the levels were found to be significantly decreased after therapy [134.594±0.87 vs 121.1281±0.69, (mean± SEM)] as compared to pre-treatment values (p<0.05). Significant differences were found in miR-144 levels among PTB patients, before and after treatment, compared with the controls (all p < 0.05).

Conclusion: As sputum miR-144 levels were significantly up-regulated initially and decreased at the end of intensive phase, it may have a role as surrogate biomarker in the diagnosis and treatment of PTB.