Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0036690 (sepsis)
 59,461 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Fifteen patients with stage II, IIIA, and IIIB non-small cell lung cancer (NSCLC) received subcutaneous (s.c.) recombinant, glycosylated, human interferon-beta 1a (Rebif; rHuIFN-beta 1a) on each day of conventionally fractionated radiation therapy (RT) given in 2.0 Gy fractions to 60 Gy in 6 weeks. The rHuIFN-beta 1a was generated in CHO cells by recombinant DNA technology and is identical to natural IFN-beta produced by fibroblasts in primary sequence and glycosylation. Cohorts of three patients each were treated with escalating doses of rHuIFN-beta 1a: 1.5, 3, 6, 12, and 24 MIU/m2 per treatment day. Acute toxicity was assessed according to modified WHO criteria; late toxicity was graded using RTOG late toxicity criteria. The maximum tolerated dose (MTD) of rHuIFN-beta 1a was defined as the dose level immediately below that in which dose-limiting toxicity occurred in > or = two of six patients. Immunomodulatory effects and antigenicity of rHuIFN-beta 1a were assessed by 2-5A synthetase, beta 2-microglobulin, and neopterin levels and by measurement of anti-rHuIFN-beta antibodies, respectively. Fourteen of fifteen patients experienced grades 1-3 acute (early) toxicity (< or = 90 days), which was primarily gastrointestinal: dysphagia/esophagitis (14/15), nausea/vomiting (12/15), anorexia (7/15), and liver transaminasemia (6/15). One of three patients treated with 24 MIU/m2 per treatment day (total rHuIFN-beta 1a dose 672 MIU) died of complications secondary to pneumonia, sepsis, adult respiratory distress syndrome (ARDS), and radiation pneumonitis. Twelve patients were evaluable for late toxicity (> 90 days). Maximum toxicity was grade 0 in five patients, grade 1 in four patients, and grade 5 in one patient (radiation pneumonitis). Clinical responses from the combination were 1/15 CR, 6/15 PR, 6/15 stable disease, and 1/15 progressive disease. The MTD of rHuIFN-beta 1a has been estimated at 12 MIU/m2 per treatment day when given daily during conventional RT to 60 Gy in 6 weeks. Biologic response by rHuIFN-beta 1a alone was reflected by significant and dose-related increases in 2-5A synthetase, beta 2-microglobulin, and neopterin. Radiation therapy alone had no effect on these immune response parameters and did not diminish their augmentation by rHuIFN-beta 1a. There was no association of biologic modulation with clinical response or survival.
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PMID:Recombinant human interferon-beta (rHuIFN-beta) and radiation therapy for inoperable non-small cell lung cancer. 893 64

Pseudomonas aeruginosa infection, one of the major complications of burn wounds, may lead to sepsis and death. Using the Multi-Probe Template/RNase protection assay, we have compared the expression of different cytokine genes within the skin and livers of thermally injured mice infected with P. aeruginosa PAO1. Thermal injury alone enhanced or up-regulated certain cytokines, including macrophage colony-stimulating factor (M-CSF), interleukin 1 (IL-1)RI, IL-1 beta, macrophage inflammatory protein (MIP)-1 beta and MIP-2; while PAO1 challenge alone up-regulated tumour necrosis factor alpha (TNF-alpha) and transforming growth factor beta (TGF-beta) expression. The combination of thermal injury plus PAO1 infection enhanced the expression of several pro-inflammatory and haematopoietic cytokines [stem cell factor (SCF), leukocyte inhibitory factor (LIF), IL-6 and TNF-alpha]; induced the expression of granulocyte-macrophage colony-stimulating factor (GM-CSF) and G-CSF by 5 h and the expression of additional cytokines, including TGF-beta, TNF-beta, lymphotoxin beta (LT-beta), interferon gamma (IFN-gamma), and IFN-beta by 40 h post-burn/infection. While the most intense cytokine expression occurred in the skin, the majority of cytokines tested were also expressed in the liver by 40 h post-burn/infection. These results suggest that in P. aeruginosa infection of burn wounds: (1) up-regulation of the expression of different cytokines, locally and within the livers of burned mice, is an indication of P. aeruginosa -induced sepsis; and (2) IL-6 and G-CSF play an important role in the host response mechanism.
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PMID:The effects of infection of thermal injury by Pseudomonas aeruginosa PAO1 on the murine cytokine response. 1179 26

Although activation of Toll-like receptor 4 (TLR4)-positive cells is essential for eliminating Gram-negative bacteria, overactivation of these cells by the TLR4 ligand LPS initiates a systemic inflammatory reaction and shock. Here we demonstrate that SPRET/Ei mice, derived from Mus spretus, exhibit a dominant resistance against LPS-induced lethality. This resistance is mediated by bone marrow-derived cells. Macrophages from these mice exhibit normal signaling and gene expression responses that depend on the myeloid differentiation factor 88 adaptor protein, but they are impaired in IFN-beta production. The defect appears to be specific for IFN-beta, although the SPRET/Ei IFN-beta promoter is normal. In vivo IFN-beta induction by LPS or influenza virus is very low in SPRET/Ei mice, but IFN-beta-treatment restores the sensitivity to LPS, and IFN type 1 receptor-deficient mice are also resistant to LPS. Because of the defective induction of IFN-beta, these mice are completely resistant to Listeria monocytogenes and highly sensitive to Leishmania major infection. Stimulation of SPRET/Ei macrophages leads to rapid down-regulation of IFN type 1 receptor mRNA expression, which is reflected in poor induction of IFN-beta-dependent genes. This finding indicates that the resistance of SPRET/Ei mice to LPS is due to disruption of a positive-feedback loop that amplifies IFN-beta production. In contrast to TLR4-deficient mice, SPRET/Ei mice resist both LPS and sepsis induced with Klebsiella pneumoniae.
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PMID:The wild-derived inbred mouse strain SPRET/Ei is resistant to LPS and defective in IFN-beta production. 1645 98

TLRs are considered important for the control of immune responses during endotoxic shock or polymicrobial sepsis. Signaling by TLRs may proceed through the adapter proteins MyD88 or TIR domain-containing adaptor inducinng IFN-beta. Both pathways can lead to the production of type I IFNs (IFN-alphabeta). In the present study, the role of the type I IFN pathway for host defense and immune pathology in sepsis was investigated using a model of mixed bacterial peritonitis. Systemic levels of IFN-alphabeta protein were markedly elevated during septic peritonitis. More detailed analyses revealed production of IFN-beta, but not IFN-alpha subtypes, and identified CD11b+ CD11c- macrophage-like cells as major producers of IFN-beta. The results further demonstrate that in IFN-alphabeta receptor I chain (IFNARI)-deficient mice, the early recruitment of neutrophils to the infected peritoneal cavity was augmented, most likely due to an increased local production of MCP-1 and leukotriene B4. In the absence of IFNARI, peritoneal neutrophils also exhibited enhanced production of reactive oxygen intermediates and elevated expression of Mac-1. Conversely, administration of recombinant IFN-beta resulted in reduced leukotriene B4 levels and decreased peritoneal neutrophil recruitment and activation. Analysis of the cytokine response to septic peritonitis revealed that IFNARI deficiency strongly attenuated late, but not early, hyperinflammation. In accordance with these findings, bacterial clearance and overall survival of IFNARI(-/-) mice were improved. Therefore, the present study reveals critical functions of the type I IFN pathway during severe mixed bacterial infections leading to sepsis. The results suggest that type I IFN exerts predominantly adverse effects under these conditions.
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PMID:Type I IFN modulates host defense and late hyperinflammation in septic peritonitis. 1701 50

Polymicrobial sepsis alters the adaptive immune response and induces T cell suppression and Th2 immune polarization. We identify a GR-1(+)CD11b(+) population whose numbers dramatically increase and remain elevated in the spleen, lymph nodes, and bone marrow during polymicrobial sepsis. Phenotypically, these cells are heterogeneous, immature, predominantly myeloid progenitors that express interleukin 10 and several other cytokines and chemokines. Splenic GR-1(+) cells effectively suppress antigen-specific CD8(+) T cell interferon (IFN) gamma production but only modestly suppress antigen-specific and nonspecific CD4(+) T cell proliferation. GR-1(+) cell depletion in vivo prevents both the sepsis-induced augmentation of Th2 cell-dependent and depression of Th1 cell-dependent antibody production. Signaling through MyD88, but not Toll-like receptor 4, TIR domain-containing adaptor-inducing IFN-beta, or the IFN-alpha/beta receptor, is required for complete GR-1(+)CD11b(+) expansion. GR-1(+)CD11b(+) cells contribute to sepsis-induced T cell suppression and preferential Th2 polarization.
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PMID:MyD88-dependent expansion of an immature GR-1(+)CD11b(+) population induces T cell suppression and Th2 polarization in sepsis. 1754 19

Repeated exposure to low doses of endotoxin results in progressive hyporesponsiveness to subsequent endotoxin challenge, a phenomenon known as endotoxin tolerance. In spite of its clinical significance in sepsis and characterization of the TLR4 signaling pathway as the principal endotoxin detection mechanism, the molecular determinants that induce tolerance remain obscure. We investigated the role of the TRIF/IFN-beta pathway in TLR4-induced endotoxin tolerance. Lipid A-induced homotolerance was characterized by the down-regulation of MyD88-dependent proinflammatory cytokines TNF-alpha and CCL3, but up-regulation of TRIF-dependent cytokine IFN-beta. This correlated with a molecular phenotype of defective NF-kappaB activation but a functional TRIF-dependent STAT1 signaling. Tolerance-induced suppression of TNF-alpha and CCL3 expression was significantly relieved by TRIF and IFN regulatory factor 3 deficiency, suggesting the involvement of the TRIF pathway in tolerance. Alternatively, selective activation of TRIF by poly(I:C)-induced tolerance to lipid A. Furthermore, pretreatment with rIFN-beta also induced tolerance, whereas addition of IFN-beta-neutralizing Ab during the tolerization partially alleviated tolerance to lipid A but not TLR2-induced endotoxin homo- or heterotolerance. Furthermore, IFNAR1-/- murine embryonal fibroblast and bone-marrow derived macrophages failed to induce tolerance. Together, these observations constitute evidence for a role of the TRIF/IFN-beta pathway in the regulation of lipid A/TLR4-mediated endotoxin homotolerance.
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PMID:Role for MyD88-independent, TRIF pathway in lipid A/TLR4-induced endotoxin tolerance. 1778 47

The activation of p38alpha, a MAPK family member, is associated with macrophage activation by microbial pattern molecules, such as LPS. The requirement of p38alpha in inflammatory responses has been shown in a number of studies using chemical inhibitors, though the inhibitors also inhibit p38beta and perhaps some other enzymes. In this study, we used conditional knockout of p38alpha in macrophages to address the role of p38alpha in macrophage activation. We found that p38alpha deficiency causes a significant inhibition in the production of LPS-induced TNF-alpha, IL-12, and IL-18, but it has little or no effect on IL-6 or IFN-beta production. Knockout of p38alpha in macrophages did not affect LPS-induced activation of the other major signaling pathways (NF-kappaB, Jnk, and Erk), nor did it affect the transcriptional activity of NF-kappaB. It had little inhibitory effect on LPS-induced AP-1 activity, but it significantly inhibited LPS-induced C/EBP-beta and CREB activation, indicating that the role of p38alpha in cytokine production in macrophages is at least in part through its regulation of C/EBP-beta and CREB activation. In addition, we also confirmed that p38alpha is important for phagocytosis of bacteria by macrophages. Our in vivo studies with two murine models showed that p38alpha is involved in sepsis. Collectively, our data demonstrate that p38alpha is an important player in inflammatory responses.
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PMID:Macrophage deletion of p38alpha partially impairs lipopolysaccharide-induced cellular activation. 1835 33

Sepsis is a devastating condition characterized by a systemic inflammatory response. Recently, high mobility group box 1 (HMGB1) was identified as a necessary and sufficient mediator of the lethal systemic inflammation caused by sepsis. However, despite its clinical importance, the mechanism of HMGB1 release has remained to be elusive. In this study, we demonstrate that the IFN-beta-mediated JAK/STAT pathway is essential for LPS or Escherichia coli-induced HMGB1 release, which is dependent on Toll/IL-1R domain-containing adapter-inducing IFN-beta adaptor. Additionally, we show that NO acts as a downstream molecule of the IFN-beta signaling. Furthermore, the JAK inhibitor treatment as well as the STAT-1 or IFN-beta receptor deficiency reduced HMGB1 release in a murine model of endotoxemia. Our results suggest that HMGB1 release in sepsis is dependent on the IFN-beta signaling axis; thus, therapeutic agents that selectively inhibit IFN-beta signaling could be beneficial in the treatment of sepsis.
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PMID:Bacterial endotoxin induces the release of high mobility group box 1 via the IFN-beta signaling pathway. 1920 1

We examined our hypothesis that heme-oxygenase-1 (HO-1)-derived carbon monoxide (CO) inhibits the release of high-mobility group box 1 (HMGB1) in RAW264.7 cells activated with lipopolysaccharide (LPS) in vitro and in LPS- or cecal ligation and puncture (CLP)-induced septic mice in vivo, so that HO-1 induction or CO improves survival of sepsis in rodents. We found that pretreatment with HO-1 inducers (hemin, cobalt protoporphyrin IX) or transfection of HO-1 significantly inhibited HMGB1 release, which was blocked by HO-1 small interfering RNA, in cells activated by LPS. Carbon monoxide-releasing molecule 2 (CORM-2) but not bilirubin or deferoxamine inhibited HMGB1 release in LPS-activated macrophages. Oxyhemoglobin reversed the effect of HO-1 inducers on HMGB1 release. Translocation of HMGB1 from nucleus to cytosol was significantly inhibited by HO-1 inducers, CORM-2, or HO-1 transfection. Neutralizing antibodies to tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, interferon-beta, and N(omega)-nitro-L-arginine methyl ester hydrochloride but not N-[2-(cyclohexyloxyl)-4-nitrophenyl]-methane sulfonamide (NS-398) significantly inhibited HMGB1 release in LPS-activated cells. Production of TNF-alpha, IL-1beta, and IFN-beta was significantly reduced by pretreatment of HO-1 inducers, CORM-2, or HO-1 transfection in LPS-activated cells. Plasma levels of HMGB1 in mice challenged with LPS or CLP were significantly reduced by the administration of HO-1 inducers or CORM-2, which was accompanied by either reduction (pretreatment) or no change (delayed administration) of serum TNF-alpha and IL-1beta levels. Regardless of pretreatment or delayed administration, CORM-2 and hemin rescued mice from lethal endotoxemia and sepsis induced by LPS or CLP. Taken together, we concluded that HO-1-derived CO reduces HMGB1 release in LPS-activated cells and LPS- or CLP-induced animal model of sepsis.
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PMID:Heme-oxygenase-1 induction and carbon monoxide-releasing molecule inhibit lipopolysaccharide (LPS)-induced high-mobility group box 1 release in vitro and improve survival of mice in LPS- and cecal ligation and puncture-induced sepsis model in vivo. 1936 89

In vitro and in vivo experiments in mice have shown that exposure of cells to the TLR4 ligand LPS induces tolerance toward a second exposure to LPS and induces cross-tolerance to certain other TLR ligands. Recently, we found that LPS tolerance in experimental human endotoxemia and Gram-negative sepsis is associated with elevated levels of IL-1R-associated kinase M, an intracellular negative regulator of MyD88-dependent TLR signaling. In the present study, we investigated whether in vivo exposure of humans to LPS induces tolerance in circulating leukocytes to other TLR agonists that rely either on MyD88- dependent or on MyD88-independent signaling. Analysis of TNF, IL-1beta, IL-6, and IL-10 levels in whole blood demonstrated that leukocytes were hyporesponsive to ex vivo LPS restimulation 3-8 h after i.v. LPS injection (4 ng/kg). Reduced cytokine release during the same interval was also observed in whole blood further stimulated with MyD88-dependent ligands for TLR2, TLR5, and TLR7 or with whole bacteria. Strikingly, blood leukocytes were also tolerant to a ligand for TLR3, which signals solely through a MyD88-independent (Toll IL-1R domain-containing adaptor-inducing IFN-beta (TRIF)-dependent) pathway. The hyporesponsiveness of leukocytes to TLR3 ligation was associated with reduced rather than increased levels of the recently identified TRIF inhibitor SARM. Taken together, these data indicate that systemic LPS challenge of human volunteers induces cross-tolerance to multiple TLR ligands that signal in a MyD88-dependent or MyD88-independent manner and suggest that LPS exposure of human blood leukocytes may hamper the inflammatory response to various microbial components.
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PMID:In vivo lipopolysaccharide exposure of human blood leukocytes induces cross-tolerance to multiple TLR ligands. 1954 64


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