Characterization of miRNAs expression profiles and identification of potential biomarkers in leprosy.

Leprosy is an important cause of disability in the developing world. Early diagnosis is essential to allow cure and interrupt transmission of this infection. MiRNAs are important factors for host-pathogen interaction and they have been identified as biomarkers for various infectious diseases. The expression profile of 377 microRNAs were analyzed by TaqMan Low Density Array (TLDA) in skin lesions of tuberculoid and lepromatous leprosy patients, as well as skin specimens from healthy controls. In a second step, sixteen microRNAs were selected for validation experiments with qRT-PCR in skin samples from new individuals. Principal component analysis followed by logistic regression model and ROC curve analysis were performed to evaluate the diagnostic potential of selected miRNAs. Four patterns of differential expression were identified in TLDA experiment suggesting a diagnostic potential of miRNAs in leprosy. After validation experiments, a combination of four miRNAs (miR-101, miR-196b, miR-27b, miR-29c) was revealed as able to discriminate healthy control and leprosy patients with 80% sensitivity and 91% specificity. This set of miRNAs was also able to discriminate lepromatous and tuberculoid patients with sensitivity of 83% and 80% of specificity. In this work, it was possible to identify a set of miRNAs with good diagnostic potential for leprosy.