scholarly journals Detection of Neu1 Sialidase Activity in Regulating TOLL-like Receptor Activation

10.3791/2142 ◽  
2010 ◽  
Author(s):  
Schammim R. Amith ◽  
Preethi Jayanth ◽  
Trisha Finlay ◽  
Susan Franchuk ◽  
Alanna Gilmour ◽  
...  
Keyword(s):  
Receptor Activation ◽  
Toll Like Receptor ◽  
Sialidase Activity ◽  
Neu1 Sialidase

Dependence of pathogen molecule-induced Toll-like receptor activation and cell function on Neu1 sialidase

2009 ◽  
Vol 26 (9) ◽  
pp. 1197-1212 ◽  
Author(s):  
Schammim Ray Amith ◽  
Preethi Jayanth ◽  
Susan Franchuk ◽  
Sarah Siddiqui ◽  
Volkan Seyrantepe ◽  
...  
Keyword(s):  
Cell Function ◽  
Receptor Activation ◽  
Toll Like Receptor ◽  
Neu1 Sialidase

scholarly journals Neu1 Sialidase and Matrix Metalloproteinase-9 Cross-talk Is Essential for Toll-like Receptor Activation and Cellular Signaling

2011 ◽  
Vol 286 (42) ◽  
pp. 36532-36549 ◽  
Author(s):  
Samar Abdulkhalek ◽  
Schammim Ray Amith ◽  
Susan L. Franchuk ◽  
Preethi Jayanth ◽  
Merry Guo ◽  
...  
Keyword(s):  
Matrix Metalloproteinase ◽  
Cross Talk ◽  
Cellular Signaling ◽  
Receptor Activation ◽  
Matrix Metalloproteinase 9 ◽  
Toll Like Receptor ◽  
Neu1 Sialidase ◽  
Metalloproteinase 9

scholarly journals Differential Effects of Toll-Like Receptor Activation and Differential Mediation by MAP Kinases of Immune Responses in Microglial Cells

2021 ◽  
Author(s):  
Jaedeok Kwon ◽  
Christos Arsenis ◽  
Maria Suessmilch ◽  
Alison McColl ◽  
Jonathan Cavanagh ◽  
...  
Keyword(s):  
Map Kinase ◽  
Microglial Activation ◽  
Map Kinases ◽  
Mrna Level ◽  
Cell Types ◽  
Receptor Activation ◽  
Microglial Cells ◽  
Toll Like Receptor ◽  
Disease States ◽  
Nitrite Production

AbstractMicroglial activation is believed to play a role in many psychiatric and neurodegenerative diseases. Based largely on evidence from other cell types, it is widely thought that MAP kinase (ERK, JNK and p38) signalling pathways contribute strongly to microglial activation following immune stimuli acting on toll-like receptor (TLR) 3 or TLR4. We report here that exposure of SimA9 mouse microglial cell line to immune mimetics stimulating TLR4 (lipopolysaccharide—LPS) or TLR7/8 (resiquimod/R848), results in marked MAP kinase activation, followed by induction of nitric oxide synthase, and various cytokines/chemokines. However, in contrast to TLR4 or TLR7/8 stimulation, very few effects of TLR3 stimulation by poly-inosine/cytidine (polyI:C) were detected. Induction of chemokines/cytokines at the mRNA level by LPS and resiquimod were, in general, only marginally affected by MAP kinase inhibition, and expression of TNF, Ccl2 and Ccl5 mRNAs, along with nitrite production, were enhanced by p38 inhibition in a stimulus-specific manner. Selective JNK inhibition enhanced Ccl2 and Ccl5 release. Many distinct responses to stimulation of TLR4 and TLR7 were observed, with JNK mediating TNF protein induction by the latter but not the former, and suppressing Ccl5 release by the former but not the latter. These data reveal complex modulation by MAP kinases of microglial responses to immune challenge, including a dampening of some responses. They demonstrate that abnormal levels of JNK or p38 signalling in microglial cells will perturb their profile of cytokine and chemokine release, potentially contributing to abnormal inflammatory patterns in CNS disease states.

scholarly journals Toll-like Receptor Activation of Human Cells by Synthetic Triacylated Lipid A-like Molecules

2012 ◽  
Vol 287 (20) ◽  
pp. 16121-16131 ◽  
Author(s):  
Irène Dunn-Siegrist ◽  
Pierre Tissières ◽  
Geneviève Drifte ◽  
Jacques Bauer ◽  
Stéphane Moutel ◽  
...  
Keyword(s):  
Lipid A ◽  
Receptor Activation ◽  
Human Cells ◽  
Toll Like Receptor

The dysfunctional innate immune response triggered by Toll-like receptor activation is restored by TLR7/TLR8 and TLR9 ligands in cutaneous lichen planus

2014 ◽  
Vol 172 (1) ◽  
pp. 48-55 ◽  
Author(s):  
R. Domingues ◽  
G. Costa de Carvalho ◽  
L.M. da Silva Oliveira ◽  
E. Futata Taniguchi ◽  
J.M. Zimbres ◽  
...  
Keyword(s):  
Immune Response ◽  
Lichen Planus ◽  
Innate Immune Response ◽  
Receptor Activation ◽  
Innate Immune ◽  
Toll Like Receptor

scholarly journals An α-Glucan ofPseudallescheria boydiiIs Involved in Fungal Phagocytosis and Toll-like Receptor Activation

2006 ◽  
Vol 281 (32) ◽  
pp. 22614-22623 ◽  
Author(s):  
Vera Carolina B. Bittencourt ◽  
Rodrigo T. Figueiredo ◽  
Rosana B. da Silva ◽  
Diego S. Mourão-Sá ◽  
Patricia L. Fernandez ◽  
...  
Keyword(s):  
Receptor Activation ◽  
Toll Like Receptor

scholarly journals Differential Requirement for TANK-binding Kinase-1 in Type I Interferon Responses to Toll-like Receptor Activation and Viral Infection

2004 ◽  
Vol 199 (12) ◽  
pp. 1651-1658 ◽  
Author(s):  
Andrea K. Perry ◽  
Edward K. Chow ◽  
Julia B. Goodnough ◽  
Wen-Chen Yeh ◽  
Genhong Cheng
Keyword(s):  
Viral Infection ◽  
Nuclear Translocation ◽  
Sendai Virus ◽  
Cell Types ◽  
Receptor Activation ◽  
Northern Blotting ◽  
Type I ◽  
Toll Like Receptor ◽  
Embryonic Fibroblasts ◽  
Iκb Kinase

TANK-binding kinase-1 (TBK1) and the inducible IκB kinase (IKK-i) have been shown recently to activate interferon (IFN) regulatory factor-3 (IRF3), the primary transcription factor regulating induction of type I IFNs. Here, we have compared the role and specificity of TBK1 in the type I IFN response to lipopolysaccharide (LPS), polyI:C, and viral challenge by examining IRF3 nuclear translocation, signal transducer and activator of transcription 1 phosphorylation, and induction of IFN-regulated genes. The LPS and polyI:C-induced IFN responses were abolished and delayed, respectively, in macrophages from mice with a targeted disruption of the TBK1 gene. When challenged with Sendai virus, the IFN response was normal in TBK1−/− macrophages, but defective in TBK1−/− embryonic fibroblasts. Although both TBK1 and IKK-i are expressed in macrophages, only TBK1 but not IKK-i was detected in embryonic fibroblasts by Northern blotting analysis. Furthermore, the IFN response in TBK1−/− embryonic fibroblasts can be restored by reconstitution with wild-type IKK-i but not a mutant IKK-i lacking kinase activity. Thus, our studies suggest that TBK1 plays an important role in the Toll-like receptor–mediated IFN response and is redundant with IKK-i in the response of certain cell types to viral infection.

scholarly journals NFκB1 is essential to prevent the development of multiorgan autoimmunity by limiting IL-6 production in follicular B cells

2016 ◽  
Vol 213 (4) ◽  
pp. 621-641 ◽  
Author(s):  
Elisha de Valle ◽  
George Grigoriadis ◽  
Lorraine A. O’Reilly ◽  
Simon N. Willis ◽  
Mhairi J. Maxwell ◽  
...  
Keyword(s):  
B Cells ◽  
B Cell ◽  
Receptor Activation ◽  
Spontaneous Generation ◽  
B Cell Differentiation ◽  
Toll Like Receptor ◽  
Intrinsic Loss ◽  
And Function ◽  
Follicular B Cells

We examined the role of NFκB1 in the homeostasis and function of peripheral follicular (Fo) B cells. Aging mice lacking NFκB1 (Nfκb1−/−) develop lymphoproliferative and multiorgan autoimmune disease attributed in large part to the deregulated activity of Nfκb1−/− Fo B cells that produce excessive levels of the proinflammatory cytokine interleukin 6 (IL-6). Despite enhanced germinal center (GC) B cell differentiation, the formation of GC structures was severely disrupted in the Nfκb1−/− mice. Bone marrow chimeric mice revealed that the Fo B cell–intrinsic loss of NFκB1 led to the spontaneous generation of GC B cells. This was primarily the result of an increase in IL-6 levels, which promotes the differentiation of Fo helper CD4+ T cells and acts in an autocrine manner to reduce antigen receptor and toll-like receptor activation thresholds in a population of proliferating IgM+ Nfκb1−/− Fo B cells. We demonstrate that p50-NFκB1 represses Il-6 transcription in Fo B cells, with the loss of NFκB1 also resulting in the uncontrolled RELA-driven transcription of Il-6. Collectively, our findings identify a previously unrecognized role for NFκB1 in preventing multiorgan autoimmunity through its negative regulation of Il-6 gene expression in Fo B cells.

scholarly journals CO2Pneumoperitoneum Preservesβ-Arrestin 2 Content and Reduces High Mobility Group Box-1 (HMGB-1) Expression in an Animal Model of Peritonitis

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Angela Simona Montalto ◽  
Alessandra Bitto ◽  
Letteria Minutoli ◽  
Pietro Impellizzeri ◽  
Gaetano Costa ◽  
...  
Keyword(s):  
Bacterial Load ◽  
Cecal Ligation ◽  
Signal Transduction Pathway ◽  
High Mobility ◽  
Receptor Activation ◽  
High Mobility Group ◽  
Male Rats ◽  
Toll Like Receptor ◽  
To Receive ◽  
Lung And Kidney

Laparoscopy (LS) has been shown to decrease the inflammatory sequelae of endotoxemia.β-arrestin 2 plays an important function in signal transduction pathway of TLR4. High mobility group box-1 (HMGB-1) is involved in the delayed systemic inflammatory response. We investigated the effects of CO2insufflation on liver, lung, and kidney expression of bothβ-arrestin 2 and HMGB-1 during sepsis. Cecal ligation and puncture (CLP) was performed in male rats and 6 h later the animals were randomly assigned to receive a CO2pneumoperitoneum or laparotomy. Animals were euthanized; liver, lung, and kidney were removed for the evaluation ofβ-arrestin 2 and HMGB-1 expression. Immunohistochemical detection of myeloperoxidase (MPO) was investigated in lung and liver and bacterial load was determined in the peritoneal fluid. CO2pneumoperitoneum reduced peritoneal bacterial load, increased the expression ofβ-arrestin 2, and blunted the expression of the potent proinflammatory HMGB-1 in liver, lung, and kidney compared with laparotomy. Liver and lung MPO was markedly reduced in rats subjected to LS compared with laparotomy. We believe that CO2exerts an early protective effect by reducing bacterial load and likely toll-like receptor activation which in turn leads to a preservedβ-arrestin 2 expression and a reduced HMGB-1 expression.

Sign in / Sign up

Export Citation Format

Share Document