Profile of IGF-binding proteins secreted by intestinal epithelial cells changes with differentiation

1994 ◽  
Vol 267 (5) ◽  
pp. G843-G850 ◽  
Author(s):  
S. Oguchi ◽  
W. A. Walker ◽  
I. R. Sanderson
Keyword(s):  
Growth Factors ◽  
Growth Factor ◽  
Epithelial Cells ◽  
Binding Proteins ◽  
Egf Receptor ◽  
Transforming Growth Factor ◽  
Intestinal Epithelial Cells ◽  
Alpha Activity ◽  
Intestinal Epithelial ◽  
Igf I

Previous reports have shown that gastrointestinal epithelial cells produce insulin-like growth factor-binding proteins (IGF-BP), which modulate the actions of IGF. This study aims to examine the relationship between differentiation and IGF-BP secretion by human intestinal epithelial cells and the effect of growth factors on their production. Caco-2 cells were cultured in serum-free media. IGF-BP secretion into the incubation media was analyzed by Western ligand blotting and immunoblotting. Caco-2 cells produced IGF-BP-2, IGF-BP-3, and IGF-BP-4. Secretion of IGF-BP-2 and IGF-BP-3 increased with differentiation, but IGF-BP-4 secretion diminished. The effect of exogenous growth factors on IGF-BP secretion was maximal at earlier stages of differentiation. IGF-I stimulated mainly IGF-BP-3 production, but epidermal growth factor (EGF) and transforming growth factor-alpha (TGF-alpha) stimulated predominantly IGF-BP-4 secretion. Adding an anti-EGF receptor antibody to block autocrine TGF-alpha activity inhibited IGF-BP-4 production but stimulated IGF-BP-2 and IGF-BP-3. In conclusion, the profile of IGF-BP secretion changes with differentiation. IGF-I and EGF (or TGF-alpha) stimulate different types of IGF-BP, with autocrine TGF-alpha activity being a factor affecting IGF-BP production during differentiation.

Cytokine regulation of fibroblast growth factor receptor 3 IIIb in intestinal epithelial cells

1997 ◽  
Vol 272 (4) ◽  
pp. G885-G893 ◽  
Author(s):  
M. Kanai ◽  
I. Rosenberg ◽  
D. K. Podolsky
Keyword(s):  
Growth Factors ◽  
Growth Factor ◽  
Epithelial Cells ◽  
Fibroblast Growth Factor ◽  
Transforming Growth Factor ◽  
Intestinal Epithelial Cells ◽  
Interleukin 2 ◽  
Intestinal Epithelial ◽  
Fibroblast Growth ◽  
Fgf Receptor

Proliferation and function of the intestinal epithelium is modulated by a range of regulatory peptides, including cytokines and peptide growth factors. To define mechanisms integrating these regulatory systems, the effects of growth factors and cytokines on the expression of the fibroblast growth factor (FGF) receptor 3 (FGFR3) IIIb expressed on intestinal epithelial cells were examined in Caco-2 cells. Regulated expression of FGFR3 IIIb was associated with acquisition of the differentiated state. Keratinocyte growth factor (KGF), a ligand of another member of the FGF receptor family, enhanced expression of FGFR3 IIIb, but acidic FGF, the ligand for FGFR3 IIIb itself, had no effect. Epidermal growth factor and transforming growth factor-beta also markedly enhanced FGFR3 IIIb expression in a different temporal pattern. In addition, FGFR3 IIIb expression was increased 10-fold by the cytokine interleukin-2. These studies demonstrate integration between cytokines and growth factor ligand-receptor systems in intestinal epithelial cells.

Free fucose is a danger signal to human intestinal epithelial cells

2008 ◽  
Vol 99 (3) ◽  
pp. 449-454 ◽  
Author(s):  
Wai Ling Chow ◽  
Yuan Kun Lee
Keyword(s):  
Growth Factor ◽  
Epithelial Cells ◽  
Transforming Growth Factor ◽  
Intestinal Epithelial Cells ◽  
Direct Interaction ◽  
Transforming Growth Factor Β ◽  
Intestinal Lumen ◽  
Mucosal Barrier ◽  
Intestinal Epithelial ◽  
Regulated Gene Expression

Fucose is present in foods, and it is a major component of human mucin glycoproteins and glycolipids.l-Fucose can also be found at the terminal position of many cell-surface oligosaccharide ligands that mediate cell-recognition and adhesion-signalling pathways. Mucin fucose can be released through the hydrolytic activity of pathogens and indigenous bacteria, leading to the release of free fucose into the intestinal lumen. The immunomodulating effects of free fucose on intestinal epithelial cells (enterocyte-like Caco-2) were investigated. It was found that the presence ofl-fucose up regulated genes and secretion of their encoded proteins that are involved in both the innate and adaptive immune responses, possibly via the toll-like receptor-2 signalling pathway. These include TNFSF5, TNFSF7, TNF-α, IL12, IL17 and IL18.Besides modulating immune reactions in differentiated Caco-2 cells, fucose induced a set of cytokine genes that are involved in the development and proliferation of immune cells. These include the bone morphogenetic proteins (BMP) BMP2, BMP4, IL5, thrombopoietin and erythropoietin. In addition, the up regulated gene expression of fibroblast growth factor-2 may help to promote epithelial cell restitution in conjunction with the enhanced expression of transforming growth factor-β mRNA. Since the exogenous fucose was not metabolised by the differentiated Caco-2 cells as a carbon source, the reactions elicited were suggested to be a result of the direct interaction of fucose and differentiated Caco-2 cells. The presence of free fucose may signal the invasion of mucin-hydrolysing microbial cells and breakage of the mucosal barrier. The intestinal epithelial cells respond by up regulation and secretion of cytokines, pre-empting the actual invasion of pathogens.

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