title: Expression of microRNA-155 correlates positively with the expression of Toll-like receptor 7 and modulates hepatitis B virus via C/EBP-β in hepatocytes.
abstract: Effective recognition of viral infection and successive activation of antiviral innate immune responses are vital for host antiviral defence, which largely depends on multiple regulators, including Toll-like receptors (TLRs) and microRNAs. Several early reports suggest that specific TLR-mediated immune responses can control hepatitis B virus (HBV) replication and express differentially with disease outcome. Considering the versatile function of miR-155 in the TLR-mediated innate immune response, we aimed to study the association between miR-155 and TLRs and their subsequent impact on HBV replication using both a HBV-replicating stable cell line (HepG2.2.15) and HBV-infected liver biopsy and serum samples. Our results showed that miR-155 was suppressed during HBV infection and a subsequent positive correlation of miR-155 with TLR7 activation was noted. Further, ectopic expression of miR-155 in vitro reduced HBV load as evidenced from reduced viral DNA, mRNA and subsequently reduced level of secreted viral antigens (HBsAg and HBeAg). Our results further suggested that CCAAT/enhancer-binding protein-β (C/EBP-β), a positive regulator of HBV transcription, was inhibited by miR-155. Taken together, our study established a correlation between miR-155 and TLR7 during HBV infection and also demonstrated in vitro that increased miR-155 level could help to reduce HBV viral load by targeting C/EBP-β.
authors.affiliation: ICMR Virus Unit, Kolkata, ID & BG Hospital Campus, Kolkata, India.
authors.forename: N
authors.initials: N
authors.lastname: Sarkar
authors.affiliation: ICMR Virus Unit, Kolkata, ID & BG Hospital Campus, Kolkata, India.
authors.forename: R
authors.initials: R
authors.lastname: Panigrahi
authors.affiliation: ICMR Virus Unit, Kolkata, ID & BG Hospital Campus, Kolkata, India.
authors.forename: A
authors.initials: A
authors.lastname: Pal
authors.affiliation: ICMR Virus Unit, Kolkata, ID & BG Hospital Campus, Kolkata, India.
authors.forename: A
authors.initials: A
authors.lastname: Biswas
authors.affiliation: Department of Gastroenterology, SCB Medical College, Cuttack, India.|Kalinga Gastroenterology Foundation, Beam Diagnostics Premises, Cuttack, India.
authors.forename: S P
authors.initials: SP
authors.lastname: Singh
authors.affiliation: Department of Gastroenterology, SCB Medical College, Cuttack, India.
authors.forename: S K
authors.initials: SK
authors.lastname: Kar
authors.affiliation: ICMR Virus Unit, Kolkata, ID & BG Hospital Campus, Kolkata, India.
authors.forename: M
authors.initials: M
authors.lastname: Bandopadhyay
authors.affiliation: ICMR Virus Unit, Kolkata, ID & BG Hospital Campus, Kolkata, India.
authors.forename: D
authors.initials: D
authors.lastname: Das
authors.affiliation: ICMR Virus Unit, Kolkata, ID & BG Hospital Campus, Kolkata, India.
authors.forename: D
authors.initials: D
authors.lastname: Saha
authors.affiliation: Department of Medicine and Clinical Oncology, Chiba University, Graduate School of Medicine, Chiba, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Kanda
authors.affiliation: National Center for Global Health and Medicine (NCGM), Ichikawa, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Sugiyama
authors.affiliation: ICMR Virus Unit, Kolkata, ID & BG Hospital Campus, Kolkata, India.|National Institute of Cholera and Enteric Diseases, Kolkata, India.
authors.forename: S
authors.initials: S
authors.lastname: Chakrabarti
authors.affiliation: ICMR Virus Unit, Kolkata, ID & BG Hospital Campus, Kolkata, India.
authors.forename: A
authors.initials: A
authors.lastname: Banerjee
authors.affiliation: ICMR Virus Unit, Kolkata, ID & BG Hospital Campus, Kolkata, India.
authors.forename: R
authors.initials: R
authors.lastname: Chakravarty
mesh_terms: D022782:CCAAT-Enhancer-Binding Protein-beta / Q000378:metabolism*; D002460:Cell Line; D006515:Hepatitis B virus / Q000276:immunology* / Q000502:physiology; D022781:Hepatocytes / Q000276:immunology* / Q000821:virology*; D006801:Humans; D008099:Liver / Q000473:pathology / Q000821:virology*; D035683:MicroRNAs / Q000096:biosynthesis*; D051199:Toll-Like Receptor 7 / Q000096:biosynthesis*; D014779:Virus Replication
chemical_list: D022782:CCAAT-Enhancer-Binding Protein-beta; C524942:MIRN155 microRNA, human; D035683:MicroRNAs; D051199:Toll-Like Receptor 7
keywords: C/EBP-β; Toll-like receptors; chronic; hepatitis B virus; miRNA