Search results for "script"
showing 10 items of 5143 documents
Evolutionary and transcriptional analyses of a pentraxin-like component family involved in the LPS inflammatory response of Ciona robusta
2020
Pentraxins (PTXs) are a superfamily of conserved proteins which are components of the humoral arm of innate immunity. They are considered to be functional ancestors of antibodies and are classified into short and long types. In this study, we show that a pentraxin-like component (Ptx-like) with a C-terminal PTX domain, highly homologous to the short PTX of H. sapiens CRP, and a long N-terminal domain typical of long PTXs, is involved in the inflammatory response of Ciona robusta under LPS exposure in vivo. Analyses of protein domains as well as 3D modelling and phylogenetic tree supported the close relationship of Ptx-like with mammalian CRP, suggesting that C. robusta Ptx-like shares a com…
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…
Adaptive suppression of the ATF4–CHOP branch of the unfolded protein response by toll-like receptor signalling
2009
The endoplasmic reticulum (ER) unfolded protein response (UPR) restores equilibrium to the ER, but prolonged expression of the UPR effector CHOP (GADD153) is cytotoxic. We found that CHOP expression induced by ER stress was suppressed by prior engagement of toll-like receptor (TLR) 3 or 4 through a TRIF-dependent pathway. TLR engagement did not suppress phosphorylation of PERK or eIF-2alpha, which are upstream of CHOP, but phospho-eIF-2alpha failed to promote translation of the CHOP activator ATF4. In mice subjected to systemic ER stress, pretreatment with low dose lipopolysaccharide (LPS), a TLR4 ligand, suppressed CHOP expression and apoptosis in splenic macrophages, renal tubule cells an…
In Vitro Expression of the Endothelial Phenotype: Comparative Study of Primary Isolated Cells and Cell Lines, Including the Novel Cell Line HPMEC-ST1…
2002
Endothelial cell lines are commonly used in in vitro studies to avoid problems associated with the use of primary endothelial cells such as the presence of contaminating cells, the difficulty in obtaining larger numbers of cells, as well as the progressive loss of cell viability and expression of endothelial markers in the course of in vitro propagation. We have analyzed the characteristics defining distinctive endothelial phenotypes in the cell lines EA.hy926, ECV304, EVLC2, HAEND, HMEC-1, ISO-HAS-1 and a cell line recently generated in our laboratory, HPMEC-ST1.6R, and have compared these phenotypes with those found in primary human endothelial cells isolated from umbilical vein (HUVEC), …
Resveratrol decreases the levels of miR-155 by upregulating miR-663, a microRNA targeting JunB and JunD.
2010
An inflammatory component is present in the microenvironment of most neoplastic tissues, including those not causally related to an obvious inflammatory process. Several microRNAs, and especially miR-155, play an essential role in both the innate and adaptative immune response. Resveratrol (trans-3,4#,5-trihydroxystilbene) is a natural antioxidant with anti-inflammatory properties that is currently at the stage of preclinical studies for human cancer prevention. Here, we establish that, in human THP-1 monocytic cells as well as in human blood monocytes, resveratrol upregulates miR- 663, a microRNA potentially targeting multiple genes implicated in the immune response. In THP-1 cells, miR-66…
Modulation of protein tyrosine nitration and inflammatory mediators by isoprenylhydroquinone glucoside.
2007
The nitration of tyrosine caused by peroxynitrite and other reactive nitrogen species is clearly detrimental for some physiological processes; however, its signalling role is still open to controversy. Among the natural phenolics known for their ability to oppose free tyrosine nitration, isoprenylhydroquinone glucoside is investigated due to its unusual structure, which contains a simple hydroxybenzene alkylated by a hemiterpenoid moiety. This hydroquinone was shown to be an effective inhibitor of peroxynitrite-induced protein tyrosine nitration in 3T3 fibroblasts. When tested on bovine seroalbumin nitration, however, the potency was reduced by half and the effect was almost abolished in th…
Phenolic-glycolipid-1 and lipoarabinomannan preferentially modulate TCR- and CD28-triggered proximal biochemical events, leading to T-cell unresponsi…
2012
Abstract Background Advanced stages of leprosy show T cell unresponsiveness and lipids of mycobacterial origin are speculated to modulate immune responses in these patients. Present study elucidates the role of phenolicglycolipid (PGL-1) and Mannose-capped lipoarabinomannan (Man-LAM) on TCR- and TCR/CD28- mediated signalling. Results We observed that lipid antigens significantly inhibit proximal early signalling events like Zap-70 phosphorylation and calcium mobilization. Interestingly, these antigens preferentially curtailed TCR-triggered early downstream signalling events like p38 phosphorylation whereas potentiated that of Erk1/2. Further, at later stages inhibition of NFAT binding, IL-2…
NFATc1 Induction in Peripheral T and B Lymphocytes
2013
Abstract NFAT transcription factors control the proliferation and survival of peripheral lymphocytes. We have reported previously that the short isoform NFATc1/αA whose generation is induced by immune receptor stimulation supports the proliferation and inhibits the activation-induced cell death of peripheral T and B cells. We will show in this study that in novel bacterial artificial chromosome transgenic mice that express EGFP under the control of entire Nfatc1 locus the Nfatc1/Egfp transgene is expressed as early as in double-negative thymocytes and in nonstimulated peripheral T and B cells. Upon immune receptor stimulation, Nfatc1/Egfp expression is elevated in B, Th1, and Th2 cells, but…
Expressional control of the ‘constitutive’ isoforms of nitric oxide synthase (NOS I and NOS III)
1998
Nitric oxide synthase (NOS) exists in three established isoforms. NOS I (NOS1, ncNOS) was originally discovered in neurons. This enzyme and splice variants thereof have since been found in many other cells and tissues. NOS II (NOS2, iNOS) was first identified in murine macrophages, but can also be induced in many other cell types. NOS III (NOS3, ecNOS) is expressed mainly in endothelial cells. Whereas NOS II is a transcriptionally regulated enzyme, NOS I and NOS III are considered constitutively expressed proteins. However, evidence generated in recent years indicates that these two isoforms are also subject to expressional regulation. In view of the important biological functions of these …
In vitro induction of cecropin genes — an immune response in a Drosophila blood cell line
1992
The Drosophila melanogaster cell line mbn-2 was explored as a model system to study insect immune responses in vitro. This cell line is of blood cell origin, derived from larval hemocytes of the mutant lethal (2) malignant blood neoplasm (1(2)mbn). The mbn-2 cells respond to microbial substances by the activation of cecropin genes, coding for bactericidal peptides. The response is stronger than that previously described for SL2 cells, and four other tested Drosophila cell lines were totally unresponsive. Bacterial lipopolysaccharide, algal laminarin (a beta-1,3-glucan), and bacterial flagellin were strong inducers, bacterial peptidoglycan fragments gave a weaker response, whereas a formyl-m…