✦ LIBER ✦

The hepatitis B virus X protein up-regulates tumor necrosis factor α gene expression in hepatocytes

✍ Scribed by Enrique Lara-Pezzi; Pedro L. Majano; Marta Gómez-Gonzalo; Carmelo García-Monzón; Ricardo Moreno-Otero; Massimo Levrero; Manuel López-Cabrera

Publisher: John Wiley and Sons
Year: 1998
Tongue: English
Weight: 484 KB
Volume: 28
Category: Article
ISSN: 0270-9139
DOI: 10.1002/hep.510280416

No coin nor oath required. For personal study only.

✦ Synopsis

Human hepatocytes infected by hepatitis B virus (HBV) produce the proinflammatory cytokine, tumor necrosis factor (TNF-). In this study, we explored the mechanism of induction of TNF- synthesis by HBV. We found that the stable HBV-transfected hepatoma cell line, 2. 2.15, expressed high-molecular-weight (HMW) TNF- mRNAs, which were absent in the parent HepG2 cells. Treatment of 2.2.15 cells with interferon alfa (IFN-) and/or interleukin-1beta (IL-1beta) reduced both viral gene transcription and TNF- mRNA expression. Transient or stable transfection of hepatocyte-derived cell lines with HBV X protein (HBx) expression vectors induced the production of biologically active TNF-. In these cells, the HBx-induced TNF- was detected both as cell-associated and soluble forms. Luciferase gene-expression assays showed that the TNF- gene promoter contained target sequences for HBx trans-activation within the proximal region of the promoter. These results indicate that the hepatocyte TNF- synthesis induced by HBV is transcriptionally up-regulated by HBx. Thus, HBx may have a role in the induction of the intrahepatic inflammatory processes that take place during acute and chronic hepatitis B.

📜 SIMILAR VOLUMES

Tumor necrosis factor-α up-regulates glu

Tumor necrosis factor-α up-regulates glucuronosyltransferase gene expression in human brain endothelial cells and promotes T-cell adhesion

✍ Somsankar Dasgupta; Makoto Yanagisawa; Kannan Krishnamurthy; Sean S. Liour; Robe 📂 Article 📅 2007 🏛 John Wiley and Sons 🌐 English ⚖ 244 KB

## Abstract Stimulation of human brain microvascular endothelial cells (SV‐HCECs) with tumor necrosis factor‐α (TNF‐α) up‐regulates sulfoglucuronosyl paragloboside (SGPG) synthesis in a dose‐ and time‐dependent manner. After TNF‐α exposure at a concentration of 50 ng/ml for 24 hr, we observed a sev

A novel tumor necrosis factor α–responsi

A novel tumor necrosis factor α–responsive CCAAT/enhancer binding protein site regulates expression of the cartilage-derived retinoic acid–sensitive protein gene in cartilage

✍ Toshihiro Imamura; Chisako Imamura; Audrey McAlinden; Sherri R. Davies; Yukihide 📂 Article 📅 2008 🏛 John Wiley and Sons 🌐 English ⚖ 479 KB 👁 1 views

The role of protein kinase B and mitogen

The role of protein kinase B and mitogen-activated protein kinase in epidermal growth factor and tumor necrosis factor α–mediated rat hepatocyte survival and apoptosis

✍ Ruth A. Roberts; Neil H. James; Sabina C. Cosulich 📂 Article 📅 2000 🏛 John Wiley and Sons 🌐 English ⚖ 274 KB 👁 1 views

Perturbation of hepatocyte growth regulation is associated with a number of liver diseases such as fibrosis and cancer. These diseases are mediated by a network of growth factors and cytokines that regulate the induction of hepatocyte proliferation and apoptosis. In this study, we have investigated