scholarly journals Intranasal Immunization Strategy To Impede Pilin-Mediated Binding of Pseudomonas aeruginosa to Airway Epithelial Cells

2005 ◽  
Vol 73 (11) ◽  
pp. 7705-7717 ◽  
Author(s):  
Jennifer C. Hsieh ◽  
Doris M. Tham ◽  
Weijun Feng ◽  
Fan Huang ◽  
Selamawit Embaie ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Epithelial Cells ◽  
Immune Responses ◽  
Early Stage ◽  
Opportunistic Pathogen ◽  
Airway Epithelial Cells ◽  
Airway Epithelial ◽  
Exotoxin A ◽  
Tracheal Epithelial Cells

ABSTRACT Prevention of pulmonary Pseudomonas aeruginosa infections represents a critical unmet medical need for cystic fibrosis (CF) patients. We have examined the tenet that a mucosal immunization approach can reduce interactions of a piliated form of this opportunistic pathogen with respiratory epithelial cells. Vaccinations were performed using ntPEpilinPAK, a protein chimera composed of a nontoxic form of P. aeruginosa exotoxin A (ntPE), where the C-terminal loop amino acid sequence of the PAK strain pilin protein was inserted in place of the ntPE Ib domain. Intranasal (i.n.) immunization of BALB/c mice with ntPEpilinPAK generated both serum and saliva immune responses. A series of in vitro studies showed that diluted samples of saliva obtained from immunized mice reduced pilin-dependent P. aeruginosa binding to polarized human tracheal epithelial cells, protected human pulmonary epithelial cells from cytotoxic actions associated with bacterial challenge, and reduced exotoxin A toxicity. Overall, i.n. administration of ntPEpilinPAK induced mucosal and systemic immune responses that may be beneficial for blocking early stage adhesion and/or infection events of epithelial cell-P. aeruginosa interactions at oropharyngeal surfaces.

Glucocorticoids induce neutral endopeptidase in transformed human tracheal epithelial cells

1991 ◽  
Vol 260 (2) ◽  
pp. L83-L89 ◽  
Author(s):  
D. B. Borson ◽  
D. C. Gruenert
Keyword(s):  
Epithelial Cells ◽  
Cell Types ◽  
Neutral Endopeptidase ◽  
Airway Epithelial Cells ◽  
Biologically Active ◽  
Airway Epithelial ◽  
Tracheal Epithelial Cells ◽  
Endopeptidase Activity ◽  
Airway Responses

Neutral endopeptidase (NEP, also known as enkephalinase, CALLA, or EC 3.4.24.11) is a membrane-bound peptidase present in many different cell types. Previous studies have shown that it modulates the actions of a variety of biologically active peptides on several airway responses. More recent studies have demonstrated that reductions in neutral endopeptidase activity in animal airways is associated with increased responses to exogenously applied and endogenously released peptides. To study the regulation of NEP expression, we used human airway epithelial cells transformed in vitro with an origin-defective SV40 plasmid. Enzymatic activity, measured using [3H-Tyr,D-Ala2]leucine enkephalin, increased with cell density (1.4 ng/10(6) cells at 530 cells/cm2 and 21 ng/10(6) cells at confluence, 400 X 10(3) cells/cm2). In both confluent and nonconfluent cultures, the glucocorticoid budesonide increased neutral endopeptidase activity in time- and concentration-dependent fashions. Maximal increases of 10 ng/10(6) cells greater than control were observed after 6 days of incubation at 10(-7) M budesonide. Dexamethasone also increased NEP, suggesting that the effect is due to glucocorticoid receptor effects. Transcription, as assessed by Northern blot analysis of total cellular RNA, showed that NEP-specific RNAs also increased with increasing concentration of glucocorticoid. We conclude that neutral endopeptidase can be increased by cell growth or density and by glucocorticoids and that the effects of glucocorticoids are mediated by increased NEP gene expression.

NF-κB activation and sustained IL-8 gene expression in primary cultures of cystic fibrosis airway epithelial cells stimulated with Pseudomonas aeruginosa

2005 ◽  
Vol 288 (3) ◽  
pp. L471-L479 ◽  
Author(s):  
Theresa Joseph ◽  
Dwight Look ◽  
Thomas Ferkol
Keyword(s):  
Cystic Fibrosis ◽  
Pseudomonas Aeruginosa ◽  
Epithelial Cells ◽  
Inflammatory Response ◽  
Cell Cultures ◽  
Primary Cultures ◽  
Airway Epithelial Cells ◽  
Mrna Levels ◽  
Airway Epithelial

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-κB (NF-κB) 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-κB in cells isolated from five CF (ΔF508/ΔF508) and three non-CF (NCF) patients in response to Pseudomonas aeruginosa. Immunofluorescence, gel-shift, and immunoblot assays demonstrated a rapid translocation of NF-κB 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-κB activation compared with NCF cells. Additionally, elevated nuclear levels of the NF-κB inhibitor IκBα 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-κB to nuclei of primary CF epithelial cell cultures, but intranuclear IκBα 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.

Inhaled marijuana smoke disrupts mitochondrial energetics in pulmonary epithelial cells in vivo

2006 ◽  
Vol 290 (6) ◽  
pp. L1202-L1209 ◽  
Author(s):  
Theodore A. Sarafian ◽  
Nancy Habib ◽  
Michael Oldham ◽  
Navindra Seeram ◽  
Ru-Po Lee ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Mitochondrial Function ◽  
A549 Cells ◽  
Cross Flow ◽  
Airway Epithelial Cells ◽  
Airway Epithelial ◽  
Red Fluorescence ◽  
Tracheal Epithelial Cells

Habitual marijuana smoking is associated with inflammation and atypia of airway epithelium accompanied by symptoms of chronic bronchitis. We hypothesized that Δ9-tetrahydrocannabinol (THC), the primary psychoactive component of marijuana, might contribute to these findings by impairing cellular energetics and mitochondrial function. To test this hypothesis, we examined particulate smoke extracts from marijuana cigarettes, tobacco cigarettes, and placebo marijuana (0% THC) cigarettes for their effects on the mitochondrial function of A549 cells in vitro. Only extracts prepared from marijuana cigarettes altered mitochondrial staining by the potentiometric probe JC-1. With the use of a cross-flow, nose-only inhalation system, rats were then exposed for 20 min to whole marijuana smoke and examined for its effects on airway epithelial cells. Inhalation of marijuana smoke produced lung tissue concentrations of THC that were 8–10 times higher than those measured in blood (75 ± 38 ng/g wet wt tissue vs. 9.2 ± 2.0 ng/ml), suggesting high local exposure. Intratracheal infusion of JC-1 immediately following marijuana smoke exposure revealed a diffuse decrease in lung cell JC-1 red fluorescence compared with tissue from unexposed or placebo smoke-exposed rats. Exposure to marijuana smoke in vivo also decreased JC-1 red fluorescence (54% decrease, P < 0.01) and ATP levels (75% decrease, P < 0.01) in single-cell preparations of tracheal epithelial cells. These results suggest that inhalation of marijuana smoke has deleterious effects on airway epithelial cell energetics that may contribute to the adverse pulmonary consequences of marijuana smoking.

The effect of anti-exotoxin a on the adherence of pseudomonas aeruginosa to hamster tracheal epithelial cells in vitro

1994 ◽  
Vol 26 (2) ◽  
pp. 181-188 ◽  
Author(s):  
P.C. Moller ◽  
M.J. Evans ◽  
R.C. Fader ◽  
L.C. Henson ◽  
B. Rogers ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Epithelial Cells ◽  
Exotoxin A ◽  
Tracheal Epithelial Cells ◽  
Tracheal Epithelial

scholarly journals Early Reduction of SARS-CoV-2 Replication in Bronchial Epithelium by Kinin B2 Receptor Antagonism

2021 ◽  
Author(s):  
Constanze A. Jakwerth ◽  
Martin Feuerherd ◽  
Ferdinand M. Guerth ◽  
Madlen Oelsner ◽  
Linda Schellhammer ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Airway Inflammation ◽  
Early Stage ◽  
Bronchial Epithelium ◽  
Airway Epithelial Cells ◽  
Airway Epithelial ◽  
Inflammation Model ◽  
Protection Potential

Background: SARS-CoV2 has evolved to enter the host via the ACE2 receptor which is part of the Kinin-kallirein pathway. This complex pathway is only poorly understood in context of immune regulation but critical to control infection. This study examines SARS-CoV2 infection and epithelial mechanisms of the kinin-kallikrein system at the kinin B2 receptor level in SARS-CoV-2 infection that is of direct translational relevance. Methods: From acute SARS-CoV-2-positive patients and -negative controls, transcriptomes of nasal brushings were analyzed. Primary airway epithelial cells (NHBEs) were infected with SARS-CoV-2 and treated with the approved B2R antagonist icatibant. SARS-CoV-2 RNA RT-qPCR, cytotoxicity assays, plaque assays and transcriptome analyses were performed. The treatment effect was further studied in a murine airway inflammation model in vivo. Results: Here, we report a broad and strong upregulation of kallikreins and the kinin B2 receptor (B2R) in the nasal mucosa of acutely symptomatic SARS-CoV-2-positive patients. A B2R antagonist impeded SARS-CoV-2 replication and spread in NHBEs, as determined in plaque assays on Vero E6 cells. B2R antagonism reduced the expression of SARS-CoV-2 entry receptor ACE2 in vitro and in a murine airway inflammation model in vivo. In addition, it suppressed gene expression broadly, particularly genes involved in G-protein-coupled-receptor signaling and ion transport. Conclusions: In summary, this study provides evidence that treatment with B2R antagonists protects airway epithelial cells from SARS-CoV-2 by inhibiting its replication and spread, through the reduction of ACE2 levels and the interference with several cellular signaling processes. Future clinical studies need to shed light on the airway protection potential of approved B2R antagonists, like icatibant, in the treatment of early-stage COVID-19.

scholarly journals Eosinophil Responses at the Airway Epithelial Barrier during the Early Phase of Influenza a Virus Infection in C57BL/6 Mice

Cells ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 509 ◽  
Author(s):  
Meenakshi Tiwary ◽  
Robert J. Rooney ◽  
Swantje Liedmann ◽  
Kim S. LeMessurier ◽  
Amali E. Samarasinghe
Keyword(s):  
Epithelial Cells ◽  
Influenza A Virus ◽  
Early Phase ◽  
Influenza A ◽  
Airway Epithelial Cells ◽  
Epithelial Barrier ◽  
Virus Infectivity ◽  
Airway Epithelial ◽  
In Vivo Models

Eosinophils, previously considered terminally differentiated effector cells, have multifaceted functions in tissues. We previously found that allergic mice with eosinophil-rich inflammation were protected from severe influenza and discovered specialized antiviral effector functions for eosinophils including promoting cellular immunity during influenza. In this study, we hypothesized that eosinophil responses during the early phase of influenza contribute to host protection. Using in vitro and in vivo models, we found that eosinophils were rapidly and dynamically regulated upon influenza A virus (IAV) exposure to gain migratory capabilities to traffic to lymphoid organs after pulmonary infection. Eosinophils were capable of neutralizing virus upon contact and combinations of eosinophil granule proteins reduced virus infectivity through hemagglutinin inactivation. Bi-directional crosstalk between IAV-exposed epithelial cells and eosinophils occurred after IAV infection and cross-regulation promoted barrier responses to improve antiviral defenses in airway epithelial cells. Direct interactions between eosinophils and airway epithelial cells after IAV infection prevented virus-induced cytopathology in airway epithelial cells in vitro, and eosinophil recipient IAV-infected mice also maintained normal airway epithelial cell morphology. Our data suggest that eosinophils are important in the early phase of IAV infection providing immediate protection to the epithelial barrier until adaptive immune responses are deployed during influenza.

Immune responses of porcine airway epithelial cells to poly(I:C), a synthetic analogue of viral double-stranded RNA

2015 ◽  
Vol 95 (1) ◽  
pp. 13-20 ◽  
Author(s):  
Xiu-qin Yang ◽  
Liang Wang ◽  
Hai-tao Li ◽  
Di Liu
Keyword(s):  
Epithelial Cells ◽  
Immune Responses ◽  
Digital Gene Expression ◽  
Enrichment Analysis ◽  
Airway Epithelial Cells ◽  
Poly I:C ◽  
Synthetic Analogue ◽  
Airway Epithelial ◽  
Transcriptional Responses ◽  
Double Stranded Rna

Yang, X.-q., Wang, L., Li, H.-t. and Liu, D. 2015. Immune responses of porcine airway epithelial cells to poly(I:C), a synthetic analogue of viral double-stranded RNA. Can. J. Anim. Sci. 95: 13–20. Swine respiratory disease (SRD) is one of the most economically important diseases affecting the pig industry. The main infectious agents that cause SRD are viruses, but the molecular pathogenesis of viral SRD has not been extensively studied. Here, using digital gene expression tag profiling, the global transcriptional responses to poly(I:C), a synthetic analogue of viral double-stranded RNA, was analyzed in porcine airway epithelial cells (PAECs). The profiling analysis revealed numerous differentially expressed genes (DEGs), including unknown sequences in the porcine nucleotide databases. Gene ontology enrichment analysis showed that DEGs were mainly enriched in response to stress (GO: 0006950), of which, defense response is one sub-process. Poly(I:C) challenge induced a general inflammation response as indicated by marked upregulation of a variety of pathogen recognition receptors, interferon-stimulated genes, proinflammatory cytokines, and chemokines, together with the significant downregulation of anti-inflammatory molecules. Furthermore, the antiapoptotic pathway was triggered, as demonstrated by the significant suppression of molecules involved in the induction of apoptosis, together with the significant stimulation of putative inhibitor of apoptosis. The results indicate that PAECs initiated defense against poly(I:C) challenge through the inflammation responses, whereas poly(I:C) can utilize antiapoptotic pathway to evade host defense.

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