Premium
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
Author(s) -
Sarkar N.,
Panigrahi R.,
Pal A.,
Biswas A.,
Singh S. P.,
Kar S. K.,
Bandopadhyay M.,
Das D.,
Saha D.,
Kanda T.,
Sugiyama M.,
Chakrabarti S.,
Banerjee A.,
Chakravarty R.
Publication year - 2015
Publication title -
journal of viral hepatitis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.329
H-Index - 100
eISSN - 1365-2893
pISSN - 1352-0504
DOI - 10.1111/jvh.12390
Subject(s) - hepatitis b virus , mir 155 , innate immune system , biology , virology , viral replication , immune system , viral load , hepatitis b virus pre beta , microrna , cccdna , virus , toll like receptor , immunology , hepatitis b , gene , hepatitis b virus dna polymerase , hbsag , biochemistry
Summary 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 ( TLR s) and micro RNA s. 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 TLR s 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 TLR 7 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 ( HB sAg and HB eAg). 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 TLR 7 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 .