Search results for "Intestin"
showing 10 items of 2215 documents
Upregulated transcription of phenoloxidase genes in the pharynx and endostyle of Ciona intestinalis in response to LPS
2015
We investigated the role of phenoloxidases (POs) in ascidians inflammatory reaction, a components of a copper-containing protein family involved in invertebrate immune system. In Ciona intestinalis two phenoloxidases (CinPO-1, CinPO-2) have been sequenced. In the present study, real time PCR analysis showed that both CinPO-1 and CinPO-2 genes were modulated by LPS inoculation suggesting that they are inducible and highly expressed in the inflamed pharynx. In situ hybridization disclosed CinPO-1 and CinPO-2 transcripts in pharynx hemocytes (granulocytes) and, mainly, in unilocular refractile granulocytes (URG) which mainly populated the inflamed tunic matrix. Interestingly, the genes are als…
Alkaline Phosphatase: Keeping the Peace at the Gut Epithelial Surface
2007
Vertebrates harbor abundant lipopolysaccharide (LPS) or endotoxin in their gut microbiota. Here we demonstrate that the brush border enzyme intestinal alkaline phosphatase (Iap), which dephosphorylates LPS, is induced during establishment of the microbiota and plays a crucial role in promoting mucosal tolerance to gut bacteria in zebrafish. We demonstrate that Iap deficient animals are hypersensitive to LPS toxicity through a mechanism mediated by Myd88 and Tumor Necrosis Factor Receptor (Tnfr). We further show that the endogenous microbiota establish the normal homeostatic level of neutrophils in the intestine through a process involving Myd88 and Tnfr. Iap deficient animals exhibit excess…
Hypoxia-inducible factor 1 alpha expression increases during colorectal carcinogenesis and tumor progression
2008
Abstract Background Hypoxia-inducible factor 1 alpha (HIF-1α) is involved in processes promoting carcinogenesis of many tumors. However, its role in the development of colorectal cancer is unknown. To investigate the significance of HIF-1α during colorectal carcinogenesis and progression we examined its expression in precursor lesions constituting the conventional and serrated pathways, as well as in non-metastatic and metastatic adenocarcinomas. Methods Immunohistochemistry and Western blot is used to analyse HIF-1α expression in normal colonic mucosa, hyperplastic polyps (HPP), sessile serrated adenomas (SSA), low-grade (TA-LGD) and high-grade (TA-HGD) traditional adenomas as well as in n…
Ciona intestinalis interleukin 17-like genes expression is upregulated by LPS challenge
2015
In humans, IL-17 is a proinflammatory cytokine that plays a key role in the clearance of extracellular bacteria promoting cell infiltration and production of several cytokines and chemokines. Here, we report on three Ciona intestinalis IL-17 homologues (CiIL17-1, CiIL17-2, CiIL17-3). The gene organisation, phylogenetic tree and modelling supported the close relationship with the mammalian IL-17A and IL-17F suggesting that the C. intestinalis IL-17 genes share a common ancestor in the chordate lineages. Real time PCR analysis showed a prompt expression induced by LPS inoculation suggesting that they are involved in the first phase of inflammatory response. In situ hybridization assays disclo…
Isolation and expression of a novel MBL-like collectin cDNA enhanced by LPS injection in the body wall of the ascidian Ciona intestinalis
2009
Collectins are a family of calcium-dependent lectins that are characterized by their collagen-like domains. Considerable interest has been focused on this class of proteins because of their ability to interact with components of the complement system activating a cascade of events responsible for the activation of the innate immune system. A differential screening between LPS-challenged and naïve Ciona intestinalis has been performed allowing the isolation of a full length cDNA encoding for a 221 AA protein. In silico analysis has shown that this polypeptide displays protein domains with similarities to mannose-binding lectins. A phylogenetic analysis suggested that C. intestinalis MBL has …
Enhanced expression of a cloned and sequenced Ciona intestinalis TNFa-like (CiTNFa) gene during the LPS-induced inflammatory response.
2008
A tumor necrosis factor-alpha (TNFalpha)-like gene from Ciona intestinalis (CiTNF alpha-like) body wall challenged with bacterial lipopolysaccharide (LPS) was cloned and sequenced 4 h after LPS inoculation. An open reading frame of 936 bp encoding a propeptide of 312 amino acids (35.4 kDa) displaying a transmembrane domain from positions 7 to 29, a TACE cleavage site, and a mature peptide domain of 185 amino acids (20.9 kDa), was determined with a predicted isoelectric point of 9.4. The phylogenetic tree based on deduced amino acid sequences of invertebrate TNF-like protein and vertebrate TNFs supported the divergence between the ascidian and vertebrate TNF families, whereas D. melanogaster…
FACIT collagen (1α-chain) is expressed by hemocytes and epidermis during the inflammatory response of the ascidian Ciona intestinalis
2007
Based on previous cloning and sequencing study, real-time PCR and in situ hybridization assays of the inflamed body wall of LPS-injected Ciona intestinalis showed the enhanced gene expression of a collagen with FACIT structural features (Ci-type IX-Col 1alpha-chain). By using specific antibodies raised against an opportunely chosen Ci-type IX-Col synthetic peptide, the fibroblast property of hemocytes challenged in vitro with LPS (at 4h) was displayed by flow cytometry, while immunocytochemistry identified hemocytes with large granules (morula cells) as collagen-producing cells. Hemocyte lysate supernatant analyzed in immunoblotting contained a 60 kDa band identifiable as 1alpha-chain-Ci-ty…
Cloning and expression of a novel component of the CAP superfamily enhanced in the inflammatory response to LPS of the ascidian Ciona intestinalis.
2010
The CAP superfamily is a group of proteins that have been linked to several biological functions such as reproduction, cancer, and immune defense. A differential screening between lipopolysaccharide (LPS)-challenged and naive Ciona intestinalis has been performed to identify LPS-induced genes. This strategy has allowed the isolation of a full-length 1471-bp cDNA encoding for a 413-amino-acid protein (CiCAP). In silico analysis has shown that this polypeptide displays a modular structure with similarities to vertebrate CAP-superfamily proteins and to a collagen-binding adhesin of Streptococcus mutans. Domain organization analysis and alignment of CiCAP to other vertebrate CAP proteins have r…
Inducible lectins with galectin properties and human IL1alpha epitopes opsonize yeast during the inflammatory response of the ascidian Ciona intestin…
2007
Studies on inducible ascidian lectins may shed light on the evolutionary emergence of cytokine functions. Here, we show that the levels of opsonins, with IL1alpha-epitopes, increase in Ciona intestinalis hemolymph as a response to an inflammatory stimulus and, in particular, to intratunic injection of lipopolysaccharide (LPS). The inflammatory agent promptly (within 4 h) enhances Ca(2+)-independent serum hemagglutinating and opsonizing activities, which are both inhibited by D-galactose and D-galactosides (alpha-lactose, N-acetyl-D-lactosamine, thio-digalactoside), suggesting that anti-rabbit erythrocyte lectins with galectin properties are involved as opsonins. Inducible galectin molecules…
Transcriptomic Analyses Reveal 2 and 4 Family Members of Cytochromes P450 (CYP) Involved in LPS Inflammatory Response in Pharynx of Ciona robusta
2021
Cytochromes P450 (CYP) are enzymes responsible for the biotransformation of most endogenous and exogenous agents. The expression of each CYP is influenced by a unique combination of mechanisms and factors including genetic polymorphisms, induction by xenobiotics, and regulation by cytokines and hormones. In recent years, Ciona robusta, one of the closest living relatives of vertebrates, has become a model in various fields of biology, in particular for studying inflammatory response. Using an in vivo LPS exposure strategy, next-generation sequencing (NGS) and qRT-PCR combined with bioinformatics and in silico analyses, compared whole pharynx transcripts from naïve and LPS-exposed C. robusta…