Hepatitis C Virus-Induced Exosomal MicroRNAs and Toll-Like Receptor 7 Polymorphism Regulate B-Cell Activating Factor
Tsai-Ling Liao, Yi-Ming Chen, Shie-Liang Hsieh, Kuo-Tung Tang, Der-Yuan Chen, Ying-Ying Yang, Hung-Jen Liu, Sheng-Shun Yang
Abstract
HCV remains an important cause of liver disease worldwide. Accumulating evidence has demonstrated that HCV infection is associated with B cell lymphoproliferative disorders such as MC. Approximately half of the patients infected with HCV develop MC, but the real reason and regulatory mechanism is still uncertain. Here, we demonstrate a novel relationship between HCV-infected hepatocyte-derived exo-miRNAs, host genetic background in TLR7, and BAFF expression. We validate that HCV-induced GU-enriched miRNAs (e.g., miR-122, let-7b, and miR-206) upregulated BAFF expression through exosome transmission and TLR7 activation. This mechanism of miRNAs action is implicated in HCV-infected hepatocyte-immune system communication and is important in extrahepatic manifestation development, thus representing a possible target for HCV infection and extrahepatic diseases treatment. In addition, we show that a functional polymorphism in TLR7 is a potential predisposing factor of MC development. Our results elucidate the molecular machinery in order to better understand the association of HCV infection with autoimmunity.