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Query: UMLS:C0043167 (
pertussis
)
19,595
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The signaling events leading to the activation of integrins and firm arrest of rolling neutrophils in inflamed venules have yet to be elucidated. In vitro assays suggest that both E-selectin and chemokines can trigger arrest of rolling neutrophils, but E-selectin(-/-) mice have normal levels of adherent neutrophils in inflamed venules. To test whether chemokine-induced neutrophil arrest in vivo can be unmasked by blocking E-selectin, we investigated neutrophil adhesion in inflamed cremaster muscle venules in tumor necrosis factor (TNF)-alpha-treated CXCR2(-/-) or wild-type (WT) mice injected with E-selectin blocking monoclonal antibody (mAb) 9A9. To block chemokine receptor signaling, we investigated E-selectin(-/-) or WT mice treated with
pertussis
toxin (PTx) intravenously. Neutrophil adhesion was unchanged in CXCR2(-/-), E-selectin(-/-), PTx-treated WT, or mAb 9A9-treated WT mice. However,
TNF-alpha
-induced neutrophil adhesion was almost completely abrogated in E-selectin(-/-) mice treated with PTx and significantly reduced in CXCR2(-/-) mice treated with the E-selectin blocking mAb. In thioglycollate-induced peritonitis, PTx treatment blocked neutrophil recruitment into the peritoneum of E-selectin(-/-) mice, but had only a partial effect in WT animals. These data show that E-selectin- and chemokine-mediated arrest mechanisms are overlapping in this model and identify CXCR2 as an important neutrophil arrest chemokine in vivo.
...
PMID:CXCR2- and E-selectin-induced neutrophil arrest during inflammation in vivo. 1546 24
Complement and FcgammaR effector pathways are central triggers of immune inflammation; however, the exact mechanisms for their cooperation with effector cells and their nature remain elusive. In this study we show that in the lung Arthus reaction, the initial contact between immune complexes and alveolar macrophages (AM) results in plasma complement-independent C5a production that causes decreased levels of inhibitory FcgammaRIIB, increased levels of activating FcgammaRIII, and highly induced FcgammaR-mediated
TNF-alpha
and CXCR2 ligand production. Blockade of C5aR completely reversed such changes. Strikingly, studies of
pertussis
toxin inhibition show the essential role of G(i)-type G protein signaling in C5aR-mediated control of the regulatory FcgammaR system in vitro, and analysis of the various C5aR-, FcgammaR-, and G(i)-deficient mice verifies the importance of Galpha(i2)-associated C5aR and the FcgammaRIII-FcgammaRIIB receptor pair in lung inflammation in vivo. Moreover, adoptive transfer experiments of C5aR- and FcgammaRIII-positive cells into C5aR- and FcgammaRIII-deficient mice establish AM as responsible effector cells. AM lacking either C5aR or FcgammaRIII do not possess any such inducibility of immune complex disease, whereas reconstitution with FcgammaRIIB-negative AM results in an enhanced pathology. These data suggest that AM function as a cellular link of C5a production and C5aR activation that uses a Galpha(i2)-dependent signal for modulating the two opposing FcgammaR, FcgammaRIIB and FcgammaRIII, in the initiation of the inflammatory cascade in the lung Arthus reaction.
...
PMID:Macrophages induce the inflammatory response in the pulmonary Arthus reaction through G alpha i2 activation that controls C5aR and Fc receptor cooperation. 1572 18
Granulysin, a cationic protein produced by activated human CTL and NK cells, is cytolytic against microbial and tumor targets. In this study we show that granulysin also functions as a chemoattractant and activates monocytes to produce cytokines/chemokines. Although granulysin-mediated cytotoxicity occurs at micromolar concentrations, chemoattraction occurs in the nanomolar range, and immune activation occurs over a wide range of concentrations (nanomolar to micromolar). Granulysin causes a 2- to 7-fold increase in chemotaxis of monocytes, CD4(+), and CD8(+) memory (CD45RO) but not naive (CD45RA) T cells, NK cells, and mature, but not immature, monocyte-derived dendritic cells.
Pertussis
toxin treatment abrogates chemoattraction by granulysin, indicating involvement of G-protein-coupled receptor(s). At low concentrations (10 nM), granulysin promotes a 3- to 10-fold increase in MCP-1 and RANTES produced by monocytes and U937 cells, while a 2-fold increase in
TNF-alpha
production by LPS-stimulated monocytes requires higher concentrations of granulysin (micromolar). Taken together, these data indicate that the local concentration of granulysin is critical for the biologic activity, with high concentrations resulting in cytotoxicity while lower concentrations, presumably further from the site of granulysin release, actively recruit immune cells to sites of inflammation.
...
PMID:Granulysin, a cytolytic molecule, is also a chemoattractant and proinflammatory activator. 1584 20
Lipoxins (LX) and aspirin-triggered LX (ATL) are eicosanoids generated during inflammation via transcellular biosynthetic routes that elicit distinct anti-inflammatory and proresolution bioactions, including inhibition of leukocyte-mediated injury, stimulation of macrophage clearance of apoptotic neutrophils, repression of proinflammatory cytokine production, and inhibition of cell proliferation and migration. Recently, it was reported that aspirin induces heme oxygenase-1 (HO-1) expression on endothelial cells (EC) in a COX-independent manner, what confers protection against prooxidant insults. However, the underlying mechanisms remain unclear. In this study, we investigated whether an aspirin-triggered lipoxin A(4) stable analog, 15-epi-16-(para-fluoro)-phenoxy-lipoxin A(4) (ATL-1) was able to induce endothelial HO-1. Western blot analysis showed that ATL-1 increased HO-1 protein expression associated with increased mRNA levels on EC in a time- and concentration-dependent fashion. This phenomenon appears to be mediated by the activation of the G protein-coupled LXA(4) receptor because
pertussis
toxin and Boc-2, a receptor antagonist, significantly inhibited ATL-1-induced HO-1 expression. We demonstrate that treatment of EC with ATL-1 inhibited VCAM and E-selectin expression induced by
TNF-alpha
or IL-1beta. This inhibitory effect of the analog is modulated by HO-1 because it was blocked by SnPPIX, a competitive inhibitor that blocks HO-1 activity. Our results establish that ATL-1 induces HO-1 in human EC, revealing an undescribed mechanism for the anti-inflammatory activity of these lipid mediators.
...
PMID:Novel lipid mediator aspirin-triggered lipoxin A4 induces heme oxygenase-1 in endothelial cells. 1610 Mar 87
Endogenous interferon (IFN)-gamma negatively regulates experimental autoimmune uveoretinitis (EAU), a Th1-mediated disease. Although it is well known that IFN-gamma exerts its effects by binding to the IFN-gamma receptor (IFN-gammaR), the role that IFN-gammaR plays in the development of EAU has not been investigated. Fyn has been reported to inhibit Th2 differentiation. We aimed to investigate how endogenous IFN-gammaR and fyn, which influence Th1/Th2 differentiation, participate in the development of EAU. Sex-matched 6- to 10-week-old C57BL/6 wild-type (WT), IFN-gammaR knockout (GRKO) and fyn knockout (fyn KO) mice were compared. Mice were immunized subcutaneously with human interphotoreceptor retinoid-binding protein peptide 1-20 emulsified in Freund's complete adjuvant together with an intraperitoneal injection of Bordetella
pertussis
toxin. Three weeks later, mice were sacrificed, and their eyes and spleens were harvested for histopathologic analyses and examination of cellular immune responses, respectively. Cellular immune responses were evaluated by measuring the proliferative responses and cytokine production [interleukin (IL)-4, IL-5, IL-6, IL-13, IFN-gamma and tumor necrosis factor (TNF)-alpha] of splenocytes. The incidence of EAU was 40.0% in WT mice, 59.3% in GRKO mice and 78.6% in fyn KO mice. The average EAU score was 0.294 in WT mice, 0.917 in GRKO mice and 1.063 in fyn KO mice. Upon EAU induction, significant infiltration of eosinophils into the eyes was observed in GRKO and fyn KO mice compared to WT mice. Splenocytes from GRKO mice proliferated against the antigen and a mitogen more vigorously than those from WT and fyn KO mice. Stimulation of splenocytes with the antigen induced a higher production of IL-4, IL-6, IL-13 and IFN-gamma in GRKO mice compared to WT and fyn KO mice. In contrast, IL-5 and
TNF-alpha
were most abundantly produced by splenocytes from fyn KO mice compared to WT and GRKO mice. The incidence and mean severity of EAU were significantly higher in GRKO and fyn KO mice than in WT mice, suggesting that endogenous IFN-gammaR and fyn negatively regulate the development of EAU. The different cytokine production patterns by the GRKO and fyn KO mice indicate that the negative regulatory mechanism mediated by IFN-gammaR and fyn may differ.
...
PMID:Mice lacking the IFN-gamma receptor or fyn develop severe experimental autoimmune uveoretinitis characterized by different immune responses. 1590 35
The present study was designed to characterize the possible roles of spinally located cholera toxin (CTX)- and
pertussis
toxin (PTX)-sensitive G-proteins in pro-inflammatory cytokine induced pain behaviors. Intrathecal injection of tumor necrosis factor-alpha (
TNF-alpha
; 100 pg), interleukin-1beta (IL-1beta; 100 pg) and interferon-gamma (INF-gamma; 100 pg) showed pain behavior. Intrathecal pretreatment with CTX (0.05, 0.1 and 0.5 mg) attenuated pain behavior induced by
TNF-alpha
and INF-gamma administered intrathecally. But intrathecal pretreatment with CTX (0.05, 0.1 and 0.5 microg) did not attenuate pain behavior induced by IL-1beta. On the other hand, intrathecal pretreatment with PTX further increased the pain behavior induced by
TNF-alpha
and IL-1beta administered intrathecally, especially at the dose of 0.5 microg. But intrathecal pretreatment with PTX did not affect pain behavior induced by INF-gamma. Our results suggest that, at the spinal cord level, CTX- and PTX-sensitive G-proteins appear to play important roles in modulating pain behavior induced by pro-inflammatory cytokines administered spinally. Furthermore,
TNF-alpha
, IL-1beta and INF-gamma administered spinally appear to produce pain behavior by different mechanisms.
...
PMID:Differential modulatory effects of cholera toxin and pertussis toxin on pain behavior induced by TNF-alpha, interleukin-1beta and interferon-gamma injected intrathecally. 1597 46
Adenylate cyclase toxin (CyaA) of Bordetella
pertussis
belongs to the repeat in toxin family of pore-forming toxins, which require posttranslational acylation to lyse eukaryotic cells. CyaA modulates dendritic cell (DC) and macrophage function upon stimulation with LPS. In this study, we examined the roles of acylation and enzymatic activity in the immunomodulatory and lytic effects of CyaA. The adenylate cyclase activity of CyaA was necessary for its modulatory effects on murine innate immune cells. In contrast, acylation was not essential for the immunomodulatory function of CyaA, but was required for maximal caspase-3 activation and cytotoxic activity. The wild-type acylated toxin (A-CyaA) and nonacylated CyaA (NA-CyaA), but not CyaA with an inactive adenylate cyclase domain (iAC-CyaA), enhanced TLR-ligand-induced IL-10 and inhibited IL-12,
TNF-alpha
, and CCL3 production by macrophages and DC. In addition, both A-CyaA and NA-CyaA, but not iAC-CyaA, enhanced surface expression of CD80 and decreased CpG-stimulated CD40 and ICAM-1 expression on immature DC. Furthermore, both A-CyaA and NA-CyaA promoted the induction of murine IgG1 Abs, Th2, and regulatory T cells against coadministered Ags in vivo, whereas iAC-CyaA had more limited adjuvant activity. In contrast, A-CyaA and iAC-CyaA induced caspase-3 activation and cell death in macrophages, but these effects were considerably reduced or absent with NA-CyaA. Our findings demonstrate that the enzymatic activity plays a critical role in the immunomodulatory effects of CyaA, whereas acylation facilitates the induction of apoptosis and cell lysis, and as such, NA-CyaA has considerable potential as a nontoxic therapeutic molecule with potent anti-inflammatory properties.
...
PMID:Bordetella pertussis adenylate cyclase toxin modulates innate and adaptive immune responses: distinct roles for acylation and enzymatic activity in immunomodulation and cell death. 1600 68
Sphingosine kinase (SphK) is a conserved lipid kinase that catalyzes formation of important regulators of inter- and intracellular signaling, sphingosine-1 phosphate (S1P), and dihydrosphingosine 1-phosphate (dhS1P). In this study, we investigated the role of SphK1 in the regulation of expression of matrix metalloproteinase 1 (MMP1) in dermal fibroblasts, a key event in regulation of extra cellular matrix. We show that overexpression of SphK1 up-regulated MMP1 protein, MMP1 mRNA, and MMP1 promoter activity, and this action of SphK1 required activation of the ERK1/2-Ets1 and NF-kappaB pathways. Furthermore, experiments using SphK1 specific siRNA demonstrated that SphK1 is required for the
TNF-alpha
stimulation of MMP1. Additional data revealed a specific role of dhS1P, and not S1P, as a mediator of SphK1-dependent activation of ERK1/2 and up-regulation of MMP1. The stimulatory effect of dhS1P was sensitive to
pertussis
toxin, suggesting a possible involvement of a G-protein-coupled receptor. In contrast, S1P, but not dhS1P, stimulated the induction of COX-2, which demonstrated selective actions of these two closely related bioactive lipids. In conclusion, this study describes a novel mode of SphK1 signaling through generation of dhS1P with a key role in mediating transcriptional responses to
TNF-alpha
. This is the first report of selective function of dhS1P as compared with the better studied S1P.
...
PMID:Dihydrosphingosine 1-phosphate stimulates MMP1 gene expression via activation of ERK1/2-Ets1 pathway in human fibroblasts. 1627 91
Cell loss by apoptosis occurs in renal injury such as diabetic nephropathy.
TNF-alpha
is a cytokine that induces apoptosis and has been implicated in the pathogenesis of diabetic nephropathy. The aim was to investigate whether C-peptide or insulin could modulate
TNF-alpha
-mediated cell death in opossum kidney proximal tubular cells and to examine the mechanism(s) of any effects observed. C-peptide and insulin protect against
TNF-alpha
-induced proximal tubular cell toxicity and apoptosis. Cell viability was analyzed by methylthiazoletetrazolium assay; cell viability was reduced to 60.8 +/- 2.7% of control after stimulation with 300 ng/ml
TNF-alpha
. Compromised cell viability was reversed by pretreatment with 5 nM C-peptide or 100 nM insulin.
TNF-alpha
-induced apoptosis was detected by DNA nick-end labeling and by measuring histone associated DNA fragments using ELISA. By ELISA assay, 300 ng/ml
TNF-alpha
increased apoptosis by 145.8 +/- 4.9% compared with controls, whereas 5 nM C-peptide and 100 nM insulin reduced apoptosis to 81.6 +/- 4.8 and 77.4 +/- 3.1% of control, respectively. The protective effects of C-peptide and insulin were associated with activation of NF-kappaB. Activation of NF-kappaB by C-peptide was
pertussis
toxin sensitive and dependent on activation of Galpha(i). Phosphatidylinositol 3-kinase but not extracellular signal regulated mitogen-activated protein kinase mediated C-peptide and insulin activation of NF-kappaB. The cytoprotective effects of both C-peptide and insulin were related to increased expression of TNF receptor-associated factor 2, the product of an NF-kappaB-dependent survival gene. These data suggest that C-peptide and/or insulin activation of NF-kappaB-regulated survival genes protects against
TNF-alpha
-induced renal tubular injury in diabetes. The data further support the concept of C-peptide as a peptide hormone in its own right and suggest a potential therapeutic role for C-peptide.
...
PMID:C-peptide signals via Galpha i to protect against TNF-alpha-mediated apoptosis of opossum kidney proximal tubular cells. 1651 Jul 65
Lysophosphatidic acid (LPA) refers to a family of small phospholipid mediators that are generated in response to agonist stimulation in diverse cell types. LPA binds to G protein-coupled receptors to elicit numerous biological responses, including proliferation and inflammation. In this study, LPA production and response were characterized in a human corneal epithelial cell line, 2.040 pRSV-T. LPA levels in cells and medium are increased by exogenous 18:1 LPA (oleoyl-LPA), LPS, IL-1beta, and
TNF-alpha
. LPS, IL-1beta, and
TNF-alpha
, which mediate ocular inflammation, stimulate activation of p38, ERK, and Akt kinases in the corneal cell line. Similar responses are elicited by 18:1 LPA.
Pertussis
toxin (PTX) blocks LPA-induced activation of p38 and ERK but only slightly inhibits LPA-induced activation of Akt. All of the agonists tested, including LPA, stimulate proliferation of 2.040 pRSV-T cells. In these cells, both Akt and ERK pathways are important for LPA-induced proliferation. Thus PTX only partially suppresses the mitogenic response to LPA. Transcripts for the LPA receptors LPA(1)/EDG-2, LPA(2)/EDG-4, and LPA(3)/EDG-7 are expressed by the corneal cell line. Ki16425, an antagonist for LPA receptors, was used to explore the autocrine role of LPA. LPA-induced activations of p38, ERK, and Akt kinases, as well as proliferation, are inhibited by Ki16425. Ki16425 partially inhibits signal transduction and proliferation induced by the inflammatory agents tested. We conclude that LPA, produced in corneal epithelial cells in response to inflammatory agonists, contributes to mediating the mitogenic responses to these agonists in an autocrine fashion.
...
PMID:Lysophosphatidic acid as a mediator for proinflammatory agonists in a human corneal epithelial cell line. 1676 Feb 61
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