Daniel Ménard - Academia.edu (original) (raw)
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Papers by Daniel Ménard
FEBS Letters, 1988
In the present study, we demonstrate for the first time the presence of important concentrations ... more In the present study, we demonstrate for the first time the presence of important concentrations of EGF binding sites in isolated epithelial cells of both human fetal small intestine and colon as early as 12 weeks gestation. The pattern of EGF binding in the small intestine between 12 and 17 weeks show that binding was significantly higher (2.5fold) in younger fetuses than in older fetuses. Moreover, the fetal colon exhibited a much higher binding capacity (I .5-2.5 times) than corresponding intestinal cells for all age groups studied. Analysis of Scatchard representations reveal that the concentration of high-and low-affinity binding sites in colonic epithelial cells are twice the values observed in corresponding intestinal cells. The present data raise interesting possibilities as to the role of this growth factor in human fetal gut development. Small intestine; Colon; EGF receptor; (Human fetal, Isolated cell) from the Medical Research Council of Canada (D.M.
Experimental Cell Research, 2005
While several autocrine/paracrine growth factors (GFs) can all stimulate epithelial regeneration ... more While several autocrine/paracrine growth factors (GFs) can all stimulate epithelial regeneration in experimentally wounded primary gastric cultures, clinical relevance for their non-redundant cooperative actions in human gastric ulcer healing is suggested by the sequential pattern of GF gene induction in vivo. Using new HGE cell lines able to form a coherent monolayer with tight junctions as well as using primary human gastric epithelial cultures, we show that EGF, TGFalpha, HGF and IGFs accelerate epithelial restitution upon wounding, independently of the TGFbeta pathway (as opposed to intestinal cells). However, they differently modulate cell behavior: TGFalpha exerts strong effects (even more than EGF) on cytoplasmic spreading and non-oriented protruding activity of bordering cells whereas HGF preferentially coordinates single lamella formation, cell elongation and migration into the wound. IGF-I and IGF-II rather induce the alignment of bordering cells and maintain a compact monolayer front. The number of mitotic cells maximally increases with EGF, followed by TGFalpha and IGF-I,-II. The current study demonstrates that GFs differentially regulate the regeneration of human gastric epithelial cells through specific modulation of cell shape adaptation, migration and proliferation, further stressing that a coordination of GF activities would be necessary for the normal progression of post-wounding epithelial repair.
FEBS Letters, 1988
In the present study, we demonstrate for the first time the presence of important concentrations ... more In the present study, we demonstrate for the first time the presence of important concentrations of EGF binding sites in isolated epithelial cells of both human fetal small intestine and colon as early as 12 weeks gestation. The pattern of EGF binding in the small intestine between 12 and 17 weeks show that binding was significantly higher (2.5fold) in younger fetuses than in older fetuses. Moreover, the fetal colon exhibited a much higher binding capacity (I .5-2.5 times) than corresponding intestinal cells for all age groups studied. Analysis of Scatchard representations reveal that the concentration of high-and low-affinity binding sites in colonic epithelial cells are twice the values observed in corresponding intestinal cells. The present data raise interesting possibilities as to the role of this growth factor in human fetal gut development. Small intestine; Colon; EGF receptor; (Human fetal, Isolated cell) from the Medical Research Council of Canada (D.M.
Experimental Cell Research, 2005
While several autocrine/paracrine growth factors (GFs) can all stimulate epithelial regeneration ... more While several autocrine/paracrine growth factors (GFs) can all stimulate epithelial regeneration in experimentally wounded primary gastric cultures, clinical relevance for their non-redundant cooperative actions in human gastric ulcer healing is suggested by the sequential pattern of GF gene induction in vivo. Using new HGE cell lines able to form a coherent monolayer with tight junctions as well as using primary human gastric epithelial cultures, we show that EGF, TGFalpha, HGF and IGFs accelerate epithelial restitution upon wounding, independently of the TGFbeta pathway (as opposed to intestinal cells). However, they differently modulate cell behavior: TGFalpha exerts strong effects (even more than EGF) on cytoplasmic spreading and non-oriented protruding activity of bordering cells whereas HGF preferentially coordinates single lamella formation, cell elongation and migration into the wound. IGF-I and IGF-II rather induce the alignment of bordering cells and maintain a compact monolayer front. The number of mitotic cells maximally increases with EGF, followed by TGFalpha and IGF-I,-II. The current study demonstrates that GFs differentially regulate the regeneration of human gastric epithelial cells through specific modulation of cell shape adaptation, migration and proliferation, further stressing that a coordination of GF activities would be necessary for the normal progression of post-wounding epithelial repair.