Integrin α7β1 represses intestinal absorptive cell differentiation.

Intestinal epithelial cell differentiation is a highly controlled and orderly process occurring in the crypt so that cells migrating out to cover the villi are already fully functional. Absorptive cell precursors, which originate from the stem cell population located in the lower third of the crypt, are subject to several cycles of amplification in the transit amplifying (TA) zone, before reaching the terminal differentiation compartment located in the upper third. There is a large body of evidence that absorptive cell differentiation is halted in the TA zone through various epigenetic, transcriptional and intracellular signalling events or mechanisms allowing the transient expansion of this cell population but how these mechanisms are themself regulated remains obscure.

Fibrin(ogen) Is Constitutively Expressed by Differentiated Intestinal Epithelial Cells and Mediates Wound Healing.

Fibrinogen is a large molecule synthesized in the liver and released in the blood. Circulating levels of fibrinogen are upregulated after bleeding or clotting events and support wound healing. In the context of an injury, thrombin activation drives conversion of fibrinogen to fibrin.

Knockdown of laminin α5 stimulates intestinal cell differentiation.

Interactions between cells and the extracellular matrix regulate a wide range of cell processes such as proliferation and differentiation. Laminins are major components of the basement membrane that actively participate in most biological functions via their interactions with a variety of specific cell receptors. The α5-containing laminins (LAMA5) are one of the three main types of laminins identified at the epithelial basal lamina in the adult intestine.

Src family kinase inhibitor PP2 accelerates differentiation in human intestinal epithelial cells.

The proto-oncogene Src is an important protein tyrosine kinase involved in signaling pathways that control cell adhesion, growth, migration and survival. Here, we investigated the involvement of Src family kinases (SFKs) in human intestinal cell differentiation. We first observed that Src activity peaked in early stages of Caco-2/15 cell differentiation.

Intestinal epithelial wound healing assay in an epithelial-mesenchymal co-culture system.

Rapid and efficient healing of epithelial damage is critical to the functional integrity of the small intestine. Epithelial repair is a complex process that has largely been studied in cultured epithelium but to a much lesser extent in mucosa. We describe a novel method for the study of wound healing using a co-culture system that combined an intestinal epithelial Caco-2/15 cell monolayer cultured on top of human intestinal myofibroblasts, which together formed a basement membrane-like structure that contained many of the major components found at the epithelial-mesenchymal interface in the human intestine.

Non-conventional gas phase remediation of volatile halogenated compounds by dehydrated bacteria.

Traditional biological removal processes are limited by the low solubility of halogenated compounds in aqueous media. A new technology appears very suitable for the remediation of these volatile organic compounds (VOCs). Solid/gas bio-catalysis applied in VOC remediation can transform halogenated compounds directly in the gas phase using dehydrated cells as a bio-catalyst.

Degeneration of the pericryptal myofibroblast sheath by proinflammatory cytokines in inflammatory bowel diseases.

Background & Aims: Inflammatory bowel diseases (IBDs) are characterized by remodeling of the intestinal mucosa, which is associated with excessive cytokine release. Previous studies have shown that the epithelium in the crypt region of the mucosa in patients with Crohn's disease is susceptible to proinflammatory cytokines. We investigated whether the subepithelial myofibroblasts in this region were affected by these inflammatory conditions.

Nonconventional hydrolytic dehalogenation of 1-chlorobutane by dehydrated bacteria in a continuous solid-gas biofilter.

Rhodococcus erythropolis NCIMB 13064 and Xanthobacter autotrophicus GJ10 are able to catalyze the conversion of halogenated hydrocarbons to their corresponding alcohols. These strains are attractive biocatalysts for gas phase remediation of polluted gaseous effluents because of their complementary specificity for short or medium and for mono-, di-, or trisubstituted halogenated hydrocarbons (C2-C8 for Rhodococcus erythropolis and C1-C4 for Xanthobacter autotrophicus). After dehydration, these bacteria can catalyze the hydrolytic dehalogenation of 1-chlorobutane in a nonconventional gas phase system under a controlled water thermodynamic activity (a(w)).