A study on the possibility of using circulating microRNAs as biomarkers for the diagnosis of tubercu-losis

Abstract

Objective To evaluate the possibilities of using circulating miR-155-5p, miR-21-5p, miR-29a and miR-142-5p as biomarkers for the diagnosis of active pulmonary tuberculosis （TB）.Methods Plasma samples were collected from 60 healthy subjects, 40 patients with active pulmonary TB and 20 sub-jects with latent tuberculosis infection （ LTBI） to extract miRNAs.The levels of miR-155-5p, miR-21-5p, miR-29a and miR-142-5p in plasma samples were detected by using reverse transcription-quantitative PCR. Results The levels of miR-155-5p, miR-21-5p and miR-29a in patients with active pulmonary TB were re-spectively 10.13, 7.34 and 2.74 times as much as those in healthy subjects（P〈0.05）.No significant differences with the level of miR-142-5p were observed between the two groups.The receiver operating char-acteristic （ROC） curve analysis of miR-155-5p, miR-21-5p and miR-29a in patients with active pulmonary TB and healthy subjects showed that the areas under the curve （AUC） were respectively 0.905, 0.830 and 0.687.The level of miR-155-5p in patients with LTBI was 3.1 times than that in healthy subjects （ P〈0. 05）.No differences with miR-21-5p, miR-29a and miR-142-5p were found between patients with LTBI and healthy subjects.The levels of miR-155-5p, miR-21-5p and miR-29a in patients with active pulmonary TB were respectively 3.26, 6.69 and 1.98 times than those in patients with LTBI （P〈0.05）.The rate of LTBI was 40.58%in people who were in close contact with patients with active pulmonary TB.Conclusion Sig-nificant differences with the levels of miR-155-5p, miR-21-5p and miR-29a were observed among healthy subjects, patients with active pulmonary TB and patients with LTBI, but no difference with the level of miR-142-5p was observed among them.miR-155-5p, miR-21-5p and miR-29a could be used as the potential bio-markers for the diagnosis of active pulmonary tuberculosis and latent tuberculosis infection.People who were in close contact with patients with active pulmonary TB could have a higher LTBI rate. Key words: Pulmonary tuberculosis; miRNA; Reverse transcription quantitative PCR （qRT- PCR）