Role of microRNAs in host defense against Echinococcus granulosus infection: a preliminary assessment.

Cystic echinococcosis (CE) is a neglected helminthic zoonosis caused by the larval stage of the tapeworm Echinococcus granulosus s.l. MicroRNAs (miRNAs) are regulators of gene expression that have been linked with the pathogenesis of several human diseases, but little exists in the available literature about miRNAs in CE. Here, we investigate the expression profiles of 84 microRNAs relevant to the function of lymphocytes and other immune cells during CE infection in the peripheral blood of patients with cysts in active and inactive stages. We applied the microRNA PCR array technology to blood samples from 20 patients with a single hepatic CE cyst in either the active (CE3b) or inactive (CE4-CE5) stage. Our results show a significant upregulation of eight miRNAs (let-7g-5p, let-7a-5p, miR- 26a-5p, miR- 26b-5p, miR- 195-5p, miR- 16-5p, miR- 30c-5p, and miR- 223-3p) in patients with active cysts compared to those with inactive cysts. The high expression of these miRNAs in patients with active cysts suggests their role in a specific host immune response against the infection. Further work in this direction may help shed light on the pathogenesis of human CE.