Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The progression of lung disease in cystic fibrosis (CF) is characterized by an exuberant inflammatory response mounted by the respiratory epithelium that is further exacerbated by bacterial infection. Recent studies have demonstrated upregulation of nuclear factor-kappaB (NF-kappaB) in response to infection in genetically modified cell culture models, which is associated with expression of interleukin (IL)-8. Using human airway epithelial cells grown in primary culture, we examined in vitro activation of NF-kappaB in cells isolated from five CF (DeltaF508/DeltaF508) and three non-CF (NCF) patients in response to Pseudomonas aeruginosa. Immunofluorescence, gel-shift, and immunoblot assays demonstrated a rapid translocation of NF-kappaB subunits (p50 and p65) to the nucleus in both CF and NCF cell cultures. However, nuclear extracts from CF cells both before and following P. aeruginosa stimulation revealed elevated NF-kappaB activation compared with NCF cells. Additionally, elevated nuclear levels of the NF-kappaB inhibitor IkappaBalpha were detected in nuclei of CF cells after P. aeruginosa stimulation, but this increase was transient. There was no difference in IL-8 mRNA levels between CF and NCF cells early after stimulation, whereas expression was higher and sustained in CF cells at later times. Our results also demonstrated increased baseline translocation of NF-kappaB to nuclei of primary CF epithelial cell cultures, but intranuclear IkappaBalpha may initially block its effects following P. aeruginosa stimulation. Thus, IL-8 mRNA expression was prolonged after P. aeruginosa stimulation in CF epithelial cells, and this sustained IL-8 expression may contribute to the excessive inflammatory response in CF.
Am J Physiol Lung Cell Mol Physiol 2005 Mar
PMID:NF-kappaB activation and sustained IL-8 gene expression in primary cultures of cystic fibrosis airway epithelial cells stimulated with Pseudomonas aeruginosa. 1551 93

The hypoxia-inducible factor-1alpha (HIF-1alpha) is expressed in response to hypoxia and has been recently demonstrated in a variety of cells such as tumor cells and tumor-associated macrophages. Several characteristics of leishmanial lesions in humans and in animal models, such as microcirculation impairment, metabolic demand for leukocyte infiltration into infected tissue, parasite proliferation, and secondary bacterial infection, are strong indications of a hypoxic microenvironment in the lesions. We evaluated HIF-1alpha expression in the cutaneous lesions of BALB/c mice during Leishmania amazonensis infection. Immunohistochemical analyses of the lesions demonstrated, only in the later stages of infection when the lesion size is maximal and parasite burden is enormous and massive numbers of recruited macrophages and ulcers are observed, positive HIF-1alpha-infected cells throughout the lesions. HIF-1alpha is expressed mainly in the cytoplasm and around parasites inside the parasitophorous vacuoles of macrophages. This is the first evidence that macrophages in the microenvironment of lesions caused by a parasite produce a hypoxia-inducible factor.
Exp Mol Pathol 2005 Feb
PMID:Expression of hypoxia-inducible factor-1alpha in the cutaneous lesions of BALB/c mice infected with Leishmania amazonensis. 1559 60

Incidental observations of cancer regression following spontaneous bacterial infection have led to the preclinical development of bacteria as potential therapeutics in the treatment of cancer. A variety of natural and gene-modified bacterial species have now been explored as potential cancer treatments. The selectivity of bacterial species towards cancer will be discussed, direct bacterial oncolytic activity will be summarized and the use of bacteria as gene and/or protein delivery vehicles will be described. Preclinical and early clinical results presented indicate a high safety profile and demonstrate clear anticancer activity, thereby justifying further investigation of bacteria as a therapeutic approach in the treatment of cancer.
Curr Opin Mol Ther 2004 Dec
PMID:Bacteria in the treatment of cancer. 1566 28

From an EST fragment of the rainbow trout that was predicted to contain leucine-rich repeats (LRR), we cloned the whole cDNA and identified a soluble form of TLR5 ortholog (rtTLR5S), which does not exist in the mouse and human. rtTLR5S was about 38% homologous to the extracellular domains of human (hu) and mouse (mo)TLR5, while rtTLR5S showed <25% homologous to those of other human or mouse TLRs. A chimera constructed of rtTLR5S and the intra-cellular TIR of huTLR5 expressed on HeLa cells signaled the presence of flagellin A and C from V. anguillarum, resulting in NF-kappaB activation. The mRNA of rtTLR5S was predominantly detected in the liver. The hepatoma cell line of the rainbow trout RTH149 that responded to flagellin, allowed to up-regulate rtTLR5S in response to V. anguillarum or its purified flagellin within 8 h. rtTLR5S, when co-expressed with membrane huTLR5 in HeLa cells, augmented huTLR5-mediated NF-kappaB activation in response to flagellin. These results, together with the genome information of the pufferfish Fugu (Fugu rubripes), suggest that in fish the soluble TLR5 is an acute-phase protein sensing bacterial infection via recognition of a variety of bacterial flagellins to augment NF-kappaB activation, and may be important for fish to survive from bacterial infection in the water.
Int J Mol Med 2005 Mar
PMID:Fish soluble Toll-like receptor 5 (TLR5S) is an acute-phase protein with integral flagellin-recognition activity. 1570 48

Submucosal glands are abundant (approximately 1 gland/mm2) secretory structures in the tracheobronchial airways of the human lung. Because submucosal glands express antibacterial proteins, it has been proposed that they contribute to lung defense. However, this concept is challenged by the fact that mice do not have submucosal glands in their bronchial airways, yet are quite resistant to bacterial lung infection. The contribution of airway submucosal glands to host defense is also debated as a pathophysiologic component of cystic fibrosis lung disease. Here, we asked whether submucosal glands protect airways against bacterial infection. By comparing tracheal xenograft airways with and without glands, we found that the presence of glands enhanced bacterial killing in vivo and by airway secretions in vitro. Moreover, immunodepletion studies suggested that lysozyme is a major antibacterial component secreted by submucosal glands. These studies provide evidence that submucosal glands are a major source of antibacterials critical for maintaining sterile airways.
Am J Respir Cell Mol Biol 2005 Jun
PMID:Lysozyme secretion by submucosal glands protects the airway from bacterial infection. 1574 32

Unlike their role in bacterial infection, less is known about the role of neutrophils during pulmonary viral infection. Exposure to pollutant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD, dioxin) results in excess neutrophils in the lungs of mice infected with influenza A virus. TCDD is the most potent agonist for the aryl hydrocarbon receptor (AhR), and exposure to AhR ligands has been correlated with exacerbated inflammatory lung diseases. However, knowledge of the effects of AhR agonists on neutrophils is limited. Likewise, the factors regulating neutrophil responses during respiratory viral infections are not well characterized. To address these knowledge gaps, we determined the in vivo levels of KC, MIP-1alpha, MIP-2, LIX, IL-6, and C5a in infected mouse lungs. Our data show that these neutrophil chemoattractants are generally produced transiently in the lung within 12-24 h of infection. We also report that expression of CD11a, CD11b, CD49d, CD31, and CD38 is increased on pulmonary neutrophils in response to influenza virus. Using AhR-deficient mice, we demonstrate that excess neutrophilia in the lung is mediated by activation of the AhR and that this enhanced neutrophilia correlates directly with decreased survival in TCDD-exposed mice. Although AhR activation results in more neutrophils in the lungs, we show that this is not mediated by deregulation in levels of common neutrophil chemoattractants, expression of adhesion molecules on pulmonary neutrophils, or delayed death of neutrophils. Likewise, exposure to TCDD did not enhance pulmonary neutrophil function. This study provides an important first step in elucidating the mechanisms by which AhR agonists exacerbate pulmonary inflammatory responses.
Am J Physiol Lung Cell Mol Physiol 2005 Jul
PMID:Activation of the aryl hydrocarbon receptor increases pulmonary neutrophilia and diminishes host resistance to influenza A virus. 1579 65

Corneal endothelial cells play an important role in maintaining the transparency and ionic balance of the cornea. Inflammation causes many changes in the intracellular and extracellular environment of the cornea, including acidosis. We examined the relationship between changes in extracellular pH and expression of cyclooxygenase-2 in cultured bovine corneal endothelial cells. When extracellular pH ([pH]o) was reduced to pH 6.4, COX-2 mRNA increased, with a peak at 2 h. This was blocked by pretreatment with actinomycin D and incubation with spermine NONOate (SPER/NO, a nitric oxide donor). Exposure to the H+ ionophore, carbonyl cyanide m-chlorophenylhydrazone (CCCP), also raised COX-2 mRNA levels. CCCP-induced COX-2 mRNA expression was also reduced by SPER/NO. These results were confirmed immuno-cytochemically. These data demonstrate that COX-2 expression is stimulated by the lowering of extracellular pH that could result from bacterial infection, and that this is countered by over-production of nitric oxide, which could also result from bacterial infection.
Mol Cells 2005 Apr 30
PMID:Attenuation of extracellular acidic pH-induced cyclooxygenase-2 expression by nitric oxide. 1587 8

Mast cells are a critical component of host defense against bacterial infections. Activation of these cells during infection induces both innate and adaptive aspects of protective immunity needed for the elimination of the bacteria and survival of the host. These functional roles for the mast cell have been principally characterized using two in vivo models of acute bacterial infection featuring Gram-negative pathogens such as Escherichia coli. Here, we present basic protocols for the identification of mast cell-dependent biological functions during bacterial infection. These include the use of mast cell-deficient mice, the identification of mast cells in tissue, the culture of uropathogenic E. coli, and the basic analysis of mast cell-dependent functions in the peritoneal cavity and footpad models of bacterial pathogenesis.
Methods Mol Biol 2006
PMID:In vivo models for studying mast cell-dependent responses to bacterial infection. 1611 Jan 70

Macrolide antibiotics have clinical benefits in patients with diffuse panbronchiolitis and in patients with cystic fibrosis. Although many mechanisms have been proposed, the precise mechanisms are still uncertain. We examined the effects of erythromycin on bactericidal activity of airway surface liquid secreted by cultured human tracheal epithelial cells. Airway surface liquid was collected by washing the surface of human tracheal epithelial cells with a sodium solution (40 meq/l). Methicillin-resistant Staphylococcus aureus and Pseudomonas aeruginosa were incubated with airway surface liquid, and the number of surviving bacteria was examined. The number of bacteria in airway surface liquid from the cells cultured in medium alone was significantly lower than that in the sodium solution. Furthermore, the number of bacteria in airway surface liquid from the cells treated with erythromycin was significantly lower than that in airway surface liquid from the cells treated with solvent alone. The production of mRNA and protein of human beta-defensin-1 and human beta-defensin-2 was significantly increased by erythromycin. Bactericidal activity of airway surface liquid was observed at low concentrations (40 meq/l) of sodium but not at higher concentrations (> or =80 meq/l). Airway surface liquid did not contain significant amounts of antibiotics supplemented in the culture medium. Erythromycin at the levels in airway surface liquid and in culture medium did not inhibit bacterial growth. These results suggest that erythromycin may increase bactericidal activity of airway surface liquid in human airway epithelial cells through human beta-defensins production and reduce susceptibility of the airway to bacterial infection.
Am J Physiol Lung Cell Mol Physiol 2005 Oct
PMID:Erythromycin increases bactericidal activity of surface liquid in human airway epithelial cells. 1614 51

Inflammation resulting from bacterial infection of the respiratory mucosal surface during pneumonia and cystic fibrosis contributes to pathology. A major consequence of the inflammatory response is recruitment of polymorphonuclear cells (PMNs) to the infected site. To reach the airway, PMNs must travel through several cellular and extracellular barriers, via the actions of multiple cytokines, chemokines, and adhesion molecules. Using a model of polarized lung epithelial cells (A549 or Calu-3) grown on Transwell filters and human PMNs, we have shown that Pseudomonas aeruginosa induces PMN migration across lung epithelial barriers. The process is mediated by epithelial production of the eicosanoid hepoxilin A(3) (HXA(3)) in response to P. aeruginosa infection. HXA(3) is a PMN chemoattractant metabolized from arachidonic acid (AA). Given that release of AA is believed to be the rate-limiting step in generating eicosanoids, we investigated whether P. aeruginosa infection of lung epithelial cells resulted in an increase in free AA. P. aeruginosa infection of A549 or Calu-3 monolayers resulted in a significant increase in [(3)H]AA released from prelabeled lung epithelial cells. This was partially inhibited by PLA(2) inhibitors ONO-RS-082 and ACA as well as an inhibitor of diacylglycerol lipase. Both PLA(2) inhibitors dramatically reduced P. aeruginosa-induced PMN transmigration, whereas the diacylglycerol lipase inhibitor had no effect. In addition, we observed that P. aeruginosa infection caused an increase in the phosphorylation of cytosolic PLA(2) (cPLA(2)), suggesting a mechanism whereby P. aeruginosa activates cPLA(2) generating free AA that may be converted to HXA(3), which is required for mediating PMN transmigration.
Am J Physiol Lung Cell Mol Physiol 2006 Apr
PMID:Involvement of phospholipase A2 in Pseudomonas aeruginosa-mediated PMN transepithelial migration. 1627 74


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>