Summary auto-generated
This study investigated whether the hepatitis C virus (HCV) core protein directly contributes to liver disease by creating transgenic mice expressing the viral core gene under control of hepatitis B virus regulatory elements. Two independent transgenic mouse lines were established and analyzed for liver pathology. Beginning at two months of age, transgenic mice developed progressive hepatic steatosis (fatty infiltration of liver cells), a characteristic feature of chronic hepatitis C in humans. The steatosis worsened with age, progressing from mild in younger mice to moderate-severe in older animals. Importantly, the steatosis was not caused by elevated blood lipids or obesity, as serum cholesterol and triglycerides remained normal and body weights did not differ from control mice. The core protein was detected exclusively in liver tissue and localized to hepatocyte cytoplasm. However, other histological features of chronic hepatitis C—including bile duct damage, lymphoid follicles, hepatocyte necrosis, and inflammation—were not observed. There was no increase in cell death markers or liver enzyme elevation. These findings demonstrate that the HCV core protein alone is sufficient to induce hepatic steatosis, establishing this transgenic mouse model as a valuable tool for studying HCV pathogenesis.
Key findings
- HCV core protein expression in transgenic mice induces progressive hepatic steatosis, a hallmark pathological feature of chronic hepatitis C
- Steatosis develops without elevated serum lipids or obesity, indicating the core protein directly affects hepatocyte lipid metabolism rather than systemic lipid uptake
- The core protein is liver-specific and cytoplasm-localized in hepatocytes
- Other hepatitis C features (bile duct damage, lymphoid follicles, inflammation) were absent, suggesting additional viral proteins or immune responses are required for full hepatitis development
This summary was generated automatically from the article PDF and is not part of the original publication. Refer to the PDF for the authoritative text.
Abstract
Hepatitis C virus (HCV) is a major cause of chronic hepatitis worldwide, which finally leads to development of hepatocellular carcinoma. Chronic hepatitis C is characterized by several histological features in the liver which discriminate it from other forms of hepatitis: bile duct damage, lymphoid follicles and steatosis (fatty change). Little is known, however, about the role of HCV or its viral proteins in the pathogenesis of hepatitis. Recently, the core protein of HCV has been suggested to have a transcriptional regulatory function, and thereby to be involved in inducing phenotypic changes in hepatocytes. To clarify whether or not the HCV core protein has an effect on pathological phenotypes in the liver, two independent transgenic mouse lines carrying the HCV core gene were established. These mice developed progressive hepatic steatosis, indicating that the HCV core protein plays a direct role in the development of hepatic steatosis, which characterizes hepatitis C. This transgenic mouse system would be a good animal model for the study of pathogenesis in human HCV infection.