Expression of osteopontin correlates with portal biliary proliferation and fibrosis in biliary atresia.

Abstract

The acquired or perinatal form of biliary atresia is a Th1 fibro-inflammatory disease affecting both the extrahepatic and intrahepatic bile ducts. Osteopontin (OPN) is a Th1 cytokine implicated in several fibro-inflammatory and autoimmune diseases. We examined the expression of OPN in acquired biliary atresia in comparison to normal liver and several pediatric cholestatic liver diseases. We also assessed OPN expression by cultured human bile duct epithelial cells. We found that liver OPN mRNA and protein expression were significantly increased in biliary atresia versus normal and other cholestatic diseases. OPN expression in biliary atresia was localized to epithelium of proliferating biliary structures (ductules and/or ducts) and bile plugs contained therein. No portal biliary OPN expression could be demonstrated in normal liver, syndromic biliary atresia, biliary obstruction not due to biliary atresia, and idiopathic neonatal hepatitis. OPN expression by human bile duct epithelial cells in culture was responsive to IL-2 and TNF-alpha. Our results demonstrate an up-regulation of OPN expression by interlobular biliary epithelium in biliary atresia, which correlates with biliary proliferation and portal fibrosis. These findings suggest a role for OPN in the pathogenesis of biliary atresia.

• Authors: Peter F Whitington, Padmini Malladi, Hector Melin-Aldana, Ruba Azzam, Cara L Mack, Atul Sahai
• Journal: Pediatric research (Pediatr Res) Vol. 57 Issue 6 Pg. 837-44 (Jun 2005) ISSN: 0031-3998 [Print] United States
• PMID: 15845635 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• DNA, Complementary
• Interleukin-2
• RNA, Messenger
• SPP1 protein, human
• Sialoglycoproteins
• Tumor Necrosis Factor-alpha
• Osteopontin

Topics

• Base Sequence
• Bile Ducts (metabolism, pathology)
• Biliary Atresia (genetics, metabolism, pathology)
• Case-Control Studies
• Cells, Cultured
• Child
• Child, Preschool
• Cholestasis (genetics, metabolism, pathology)
• DNA, Complementary (genetics)
• Epithelial Cells (drug effects, metabolism)
• Fibrosis
• Gene Expression (drug effects)
• Humans
• Infant
• Infant, Newborn
• Interleukin-2 (pharmacology)
• Osteopontin
• RNA, Messenger (genetics, metabolism)
• Sialoglycoproteins (genetics, metabolism)
• Tumor Necrosis Factor-alpha (pharmacology)