Pathological impact of hepatitis B virus surface proteins on the liver is associated with the host genetic background

• Published in: PloS one 2014-03, Vol.9 (3), p.e90608-e90608
• Main Authors: Churin, Yuri, Roderfeld, Martin, Stiefel, Johannes, Würger, Tilman, Schröder, Dirk, Matono, Tomomitsu, Mollenkopf, Hans-Joachim, Montalbano, Roberta, Pompaiah, Malvika, Reifenberg, Kurt, Zahner, Daniel, Ocker, Matthias, Gerlich, Wolfram, Glebe, Dieter, Roeb, Elke
• Format: Article
• Language: English
• Subjects: Activation; Analysis; Animals; Apoptosis; Biology; c-Jun protein; CCAAT/enhancer-binding protein; Cell proliferation; Collagen; Deoxyribonucleic acid; DNA; DNA binding proteins; DNA damage; DNA microarrays; eIF-2 Kinase - metabolism; Endoplasmic reticulum; Female; Fibrosis; Gastroenterology; Gene expression; Gene Expression Regulation; Genetic aspects; Genetic engineering; Health aspects; Hepatitis; Hepatitis B; Hepatitis B - complications; Hepatitis B - genetics; Hepatitis B - metabolism; Hepatitis B - pathology; Hepatitis B virus; Hepatitis B virus - physiology; Hepatocytes; Hepatology; Histology; Homology; Host-Pathogen Interactions; House mouse; Hydroxyproline; Infection; Infections; Initiation factor eIF-2α; Kinases; Laboratory animals; Liver; Liver - metabolism; Liver - pathology; Liver - virology; Liver cancer; Liver Cirrhosis - etiology; Liver Cirrhosis - genetics; Liver diseases; Liver Neoplasms - etiology; Liver Neoplasms - genetics; Male; Medical research; Medicine; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Mice, Transgenic; Pathogenesis; Phosphorylation; Protein kinase; Protein kinases; Proteins; Regulators; Rodents; Signal Transduction; Signaling; Stat3 protein; Stellate cells; Transcription factors; Transgenic animals; Transgenic mice; Tumors; Viral Structural Proteins - genetics; Virology; Viruses; Western blotting
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0090608

While the immune pathogenesis caused by hepatitis B virus (HBV) infection has been studied extensively, little is known about direct pathogenic effects of HBV surface proteins. Here, we have investigated pathological cellular effects of HBV surface protein expression in the liver of transgenic mice with different genetic background. The impact of HBV surface protein expression on the liver was studied in two mouse strains, BALB/c and C57BL/6. Histology and hydroxyproline assays were performed to investigate liver morphology and fibrosis. Gene expression and signaling were analyzed by microarray, qPCR and Western blotting. Expression of HBV surface proteins in the liver of transgenic mice induced activation of protein kinase-like endoplasmic reticulum kinase (PERK) and eukaryotic initiation factor 2α (eIF2α) phosphorylation. Phosphorylation of eIF2α resulted in activation of the ER stress markers glucose regulated protein (GRP) 78 and pro-apoptotic C/EBP homologous protein (CHOP) in transgenic mice on BALB/c genetic background leading to stronger liver injury and fibrosis in comparison with transgenic mice on C57BL/6 background. Hepatic stellate cells represented the main collagen-producing liver cells in HBV transgenic mice. The key regulators of hepatocyte proliferation, transcription factors c-Jun and STAT3 were activated in HBV transgenic mice. Tumour incidence in transgenic mice was strain- and sex-dependent. Extent of liver injury, fibrosis, and tumour development induced by hepatic HBV surface protein expression considerably depends on host genetic background.