The constitutive expression of galectin-3 is downregulated in the intestinal epithelia of Crohn's disease patients, and tumour necrosis factor alpha decreases the level of galectin-3-specific mRNA in HCT-8 cells.

Abstract

OBJECTIVE:

Galectin-3, a lectin with specificity for beta galactoside, is expressed by a variety of cells, including intestinal epithelial cells. Among other functions, galectin-3 mediates cell adhesion and is involved in inflammatory processes. In this study, we assessed the expression of galectin-3 in intestinal epithelial cells from Crohn's disease patients (n = 10), ileum adjacent to resected colon carcinoma (n = 9), unspecific bowel inflammation (n = 1), diverticulosis (n = 1), ulcerative colitis (n = 3) and healthy jejunum used for interposition in larynx carcinoma (n = 1). The role of cytokines on galectin-3 expression was a further aim of our study.

METHODS:

The galectin-3 distribution in intestinal epithelia was analysed by immunohistochemistry, immunoblotting, immunofluorescence and reverse transcriptase polymerase chain reaction (RT-PCR). Human intestinal epithelial cell line (HCT-8) and primary cultured intestinal epithelial cells were treated with cytokines, and the effects on galectin-3 expression were determined by RT-PCR.

RESULTS:

Galectin-3 showed a homogeneous distribution in epithelia from control patients. In contrast, in epithelial cells from Crohn's disease lesions, galectin-3 staining was strongly spotted and heterogeneous. In inflamed and reorganized tissue, galectin-3 expression was markedly reduced, and was associated with disintegration of epithelia. Primary cultured epithelial cells as well as HCT-8 cells expressed galectin-3 protein and mRNA. Incubation of HCT-8 cells with tumour necrosis factor alpha (TNF-alpha), but not with other cytokines, substantially reduced galectin-3 expression as shown by semiquantitative RT-PCR.

CONCLUSIONS:

Downregulation of galectin-3 in the intestinal epithelium of Crohn's disease patients may be a consequence of enhanced TNF-alpha production by inflammatory cells, thereby contributing to the pathophysiology of the disease.

• Authors: Erika Jensen-Jarolim, Regina Gscheidlinger, Georg Oberhuber, Czilla Neuchrist, Trevor Lucas, Giovanna Bises, Christian Radauer, Martin Willheim, Otto Scheiner, Fu-Tong Liu, George Boltz-Nitulescu
• Journal: European journal of gastroenterology & hepatology (Eur J Gastroenterol Hepatol) Vol. 14 Issue 2 Pg. 145-52 (Feb 2002) ISSN: 0954-691X [Print] England
• PMID: 11981338 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antigens, Differentiation
• Cytokines
• Galectin 3
• RNA, Messenger

Topics

• Antigens, Differentiation (metabolism)
• Cell Line
• Crohn Disease (metabolism)
• Cytokines
• Down-Regulation
• Epithelial Cells (metabolism)
• Fluorescent Antibody Technique
• Galectin 3
• Humans
• Ileum (cytology)
• Immunoblotting
• Immunohistochemistry
• RNA, Messenger (analysis)
• Reverse Transcriptase Polymerase Chain Reaction