HSPB1 is an intracellular antiviral factor against hepatitis B virus

Abstract

Hepatitis B virus (HBV) is the most common of the hepatitis viruses that cause chronic liver infections in humans and it is considered a major global health problem. However, the mechanisms of HBV replication are complex and not yet fully understood. In this study, the HBV DNA-transfected HepG2.2.15 cell line and its parental HepG2 cell line were analyzed by isobaric tags for relative and absolute quantitation (iTRAQ)-coupled two-dimensional liquid chromatography tandem mass-spectrophotometry (2D LC-MS/MS), a successfully exploited high-throughput proteomic technology. In total, 2,028 unique proteins were identified and 170 proteins were differentially expressed in HepG2.2.15 cells as compared with that in HepG2. Several differentially expressed proteins were further validated by Western blot and real-time quantitative reverse transcription-PCR. Furthermore, the association of HBV replication with heat shock protein B1, one of the highly expressed proteins in HepG2.2.15 cells, was verified. HSPB1 functions as a anti-viral protein during HBV infection by specifically inducing type interferon and some downstream antiviral effectors. This study is the first to report the application of iTRAQ technology to analyze the underlying mechanisms of HBV replication. Many of the differentially expressed proteins identified have not been linked to HBV replication before, and may provide valuable novel insights into HBV replication.

Changes in glucose-6-phosphate dehydrogenase expression results in altered behavior of HBV-associated liver cancer cells

“…HepG2.2.15 cells, which contain a complete HBV genome (37), were transfected with G6PD siRNA as described above. At 48 h posttransfection, culture media were collected for measurement of HBV DNA as described previously (43). In summary, cell debris was removed by centrifugation and core particles precipitated with polyethylene glycol 8000.…”

“…The HBV DNA was precipitated with ethanol, resuspended in Tris-EDTA buffer, and digested with RNase. HBsAg or HBeAg concentrations in the supernatants of treated cell lines were measured by enzyme-linked immunosorbent assay (43).…”

C-reactive protein is a biomarker of AFP-negative HBV-related hepatocellular carcinoma

“…Supernatant HBV-DNA was quantified by RT-PCR using a commercial HBV detection kit (Fosun Diagnostics, Shanghai, China) on a Roche LightCycler instrument (Roche Molecular Systems, Alameda, CA, USA). Elecsys HBsAg II and HBeAg quantitative assay kits were used to detect HBsAg and HBeAg titers, respectively, using the Roche Cobas e601 electrochemical luminescence analyzer (Roche Diagnostics GmbH, Mannheim, Germany) (28). To measure the expression levels of downstream IFN-stimulated genes and type I IFN in transfected cells, we used gene-specific primers for GAPDH (Hs02758991_g1), OASL (Hs00984390_m1), Mx1 (Hs00895608_m1), ISG15 (Hs01921425_s1), OAS2 (Hs00942643_m1), EIF-2α (Hs00230684_m1), IFNβ1 (Hs01077958_s1), OAS1 (Hs00973637_m1), PKR (Hs00169345_m1), IFNα1 (Hs00855471_g1) and OAS3 (Hs00196324_m1) (Life Technologies).…”

Proteomics Based Identification of Autotaxin As An Anti-Hepatitis B Virus Factor and a Promoter of Hepatoma Cell Invasion and Migration

“…Supernatant HBV DNA copies were quantified by RT-PCR using a commercial HBV detection kit (Fosun Diagnostics, Shanghai, China) on a Roche LightCycler instrument (Roche Molecular Systems, Alameda, CA, USA). ElecsysHBsAg II and HBeAg quantitative assay kits were employed to detect HBsAg and HBeAg titers, respectively, in the culture medium with the Roche Cobas e601 electrochemical luminescence analyzer (Roche Diagnostics GmbH, Mannheim, Germany) [18]. …”