In hepatitis C virus (HCV)/human immunodeficiency virus (HIV) co-infected patients, HIV enhances HCV replication and liver damage. Several microRNAs (miRNAs), active in pro-fibrotic and inflammatory pathways, have been implicated in the pathogenesis of this phenomenon. However, these miRNAs have been tested only in explanted cirrhotic livers, when the liver damage has become chronic and irreversible. No data are available on the early phase of viral infection, such as early after liver transplantation (LT). In the present study, the expression of miR-101, miR-122, miR-155, miR-192, miR-200c, miR-338, and miR-532 was determined by quantitative real-time polymerase chain reaction in liver biopsies of HCV (n = 19) and HCV/HIV-infected (n = 20) LT recipients, as well as in a control group (n = 18) of noninfected patients, transplanted for alcoholic cirrhosis. The timing of liver biopsy was 6 months post-LT. None of the patients was treated with direct-acting anti-HCV drugs. All co-infected recipients had suppressed HIV viral load. Grading and staging were assessed according to the Ishak Classification. HCV and HIV viral load were measured in the sera. miR-101 (p =.03), miR-122 (p =.012), and miR-192 (p =.038) were significantly downregulated in HCV/HIV co-infected and HCV mono-infected recipients when compared with noninfected recipients, and such downregulation was more pronounced in co-infected ones. Moreover, in co-infected recipients but not in mono-infected ones, miR-101 inversely correlated with the peripheral HCV-RNA levels (r =.41, p =.04) and miR-122 inversely correlated with peripheral HCV-RNA levels (r =.49, p =.03) and with the histological grading (r =.51, p =.02). In conclusion, as early as 6 months after LT, the presence of HIV-HCV co-infection enhanced a significant downregulation of certain miRNAs that showed a direct correlation with HCV viral load and liver inflammation.
