scholarly journals Toll-Like Receptor Agonists Modulate Wound Regeneration in Airway Epithelial Cells

2018 ◽  
Vol 19 (8) ◽  
pp. 2456 ◽  
Author(s):  
Anna Lewandowska-Polak ◽  
Małgorzata Brauncajs ◽  
Marzanna Jarzębska ◽  
Małgorzata Pawełczyk ◽  
Marcin Kurowski ◽  
...  

Background: Impaired regeneration of airway epithelium may lead to persistence of inflammation and remodelling. Regeneration of injured epithelium is a complex phenomenon and the role of toll-like receptors (TLRs) in the stimulation of respiratory virus products in this process has not been established. Objective: This study was undertaken to test the hypothesis that the wound repair process in airway epithelium is modulated by microbial products via toll-like receptors. Methods: Injured and not-injured bronchial epithelial cells (ECs) (BEAS-2B line) were incubated with the TLR agonists poly(I:C), lipopolisacharide (LPS), allergen Der p1, and supernatants from virus-infected epithelial cells, either alone or in combination with TLR inhibitors. Regeneration and immune response in injured and not-injured cells were studied. Results: Addition of either poly(I:C) or LPS to ECs induced a marked inhibition of wound repair. Supernatants from RV1b-infected cells also decreased regeneration. Preincubation of injured and not-injured ECs with TLR inhibitors decreased LPS and poly(I:C)-induced repair inhibition. TGF-β and RANTES mRNA expression was higher in injured ECs and IFN-α, IFN-β, IL-8, and VEGF mRNA expression was lower in damaged epithelium as compared to not-injured. Stimulation with poly(I:C) increased IFN-α and IFN-β mRNA expression in injured cells, and LPS stimulation decreased interferons mRNA expression both in not-injured and injured ECs. Conclusion: Regeneration of the airway epithelium is modulated by microbial products via toll-like receptors.

2021 ◽  
Vol 11 (12) ◽  
pp. 1323
Author(s):  
Thomas Iosifidis ◽  
Erika N. Sutanto ◽  
Samuel T. Montgomery ◽  
Patricia Agudelo-Romero ◽  
Kevin Looi ◽  
...  

The airway epithelium of children with wheeze is characterized by defective repair that contributes to disease pathobiology. Dysregulation of developmental processes controlled by Notch has been identified in chronic asthma. However, its role in airway epithelial cells of young children with wheeze, particularly during repair, is yet to be determined. We hypothesized that Notch is dysregulated in primary airway epithelial cells (pAEC) of children with wheeze contributing to defective repair. This study investigated transcriptional and protein expression and function of Notch in pAEC isolated from children with and without wheeze. Primary AEC of children with and without wheeze were found to express all known Notch receptors and ligands, although pAEC from children with wheeze expressed significantly lower NOTCH2 (10-fold, p = 0.004) and higher JAG1 (3.5-fold, p = 0.002) mRNA levels. These dysregulations were maintained in vitro and cultures from children with wheeze displayed altered kinetics of both NOTCH2 and JAG1 expression during repair. Following Notch signaling inhibition, pAEC from children without wheeze failed to repair (wound closure rate of 76.9 ± 3.2%). Overexpression of NOTCH2 in pAEC from children with wheeze failed to rescue epithelial repair following wounding. This study illustrates the involvement of the Notch pathway in airway epithelial wound repair in health and disease, where its dysregulation may contribute to asthma development.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Nadzeya Marozkina ◽  
Laura Smith ◽  
Yi Zhao ◽  
Joe Zein ◽  
James F. Chmiel ◽  
...  

AbstractEndothelial hemoglobin (Hb)α regulates endothelial nitric oxide synthase (eNOS) biochemistry. We hypothesized that Hb could also be expressed and biochemically active in the ciliated human airway epithelium. Primary human airway epithelial cells, cultured at air–liquid interface (ALI), were obtained by clinical airway brushings or from explanted lungs. Human airway Hb mRNA data were from publically available databases; or from RT-PCR. Hb proteins were identified by immunoprecipitation, immunoblot, immunohistochemistry, immunofluorescence and liquid chromatography- mass spectrometry. Viral vectors were used to alter Hbβ expression. Heme and nitrogen oxides were measured colorimetrically. Hb mRNA was expressed in human ciliated epithelial cells. Heme proteins (Hbα, β, and δ) were detected in ALI cultures by several methods. Higher levels of airway epithelial Hbβ gene expression were associated with lower FEV1 in asthma. Both Hbβ knockdown and overexpression affected cell morphology. Hbβ and eNOS were apically colocalized. Binding heme with CO decreased extracellular accumulation of nitrogen oxides. Human airway epithelial cells express Hb. Higher levels of Hbβ gene expression were associated with airflow obstruction. Hbβ and eNOS were colocalized in ciliated cells, and heme affected oxidation of the NOS product. Epithelial Hb expression may be relevant to human airways diseases.


2015 ◽  
Vol 95 (1) ◽  
pp. 13-20 ◽  
Author(s):  
Xiu-qin Yang ◽  
Liang Wang ◽  
Hai-tao Li ◽  
Di Liu

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.


2000 ◽  
Vol 279 (2) ◽  
pp. L379-L389 ◽  
Author(s):  
Dennis W. McGraw ◽  
Susan L. Forbes ◽  
Judith C. W. Mak ◽  
David P. Witte ◽  
Patricia E. Carrigan ◽  
...  

Airway epithelial cells express β2-adrenergic receptors (β2-ARs), but their role in regulating airway responsiveness is unclear. With the Clara cell secretory protein (CCSP) promoter, we targeted expression of β2-ARs to airway epithelium of transgenic (CCSP-β2-AR) mice, thereby mimicking agonist activation of receptors only in these cells. In situ hybridization confirmed that transgene expression was confined to airway epithelium, and autoradiography showed that β2-AR density in CCSP-β2-AR mice was approximately twofold that of nontransgenic (NTG) mice. Airway responsiveness measured by whole body plethysmography showed that the methacholine dose required to increase enhanced pause to 200% of baseline (ED200) was greater for CCSP-β2-AR than for NTG mice (345 ± 34 vs. 157 ± 14 mg/ml; P < 0.01). CCSP-β2-AR mice were also less responsive to ozone (0.75 ppm for 4 h) because enhanced pause in NTG mice acutely increased to 77% over baseline ( P < 0.05) but remained unchanged in the CCSP-β2-AR mice. Although both groups were hyperreactive to methacholine 6 h after ozone exposure, the ED200for ozone-exposed CCSP-β2-AR mice was equivalent to that for unexposed NTG mice. These findings show that epithelial cell β2-ARs regulate airway responsiveness in vivo and that the bronchodilating effect of β-agonists results from activation of receptors on both epithelial and smooth muscle cells.


2015 ◽  
Vol 309 (12) ◽  
pp. C847-C855 ◽  
Author(s):  
Elizabeth R. Peitzman ◽  
Nathan A. Zaidman ◽  
Peter J. Maniak ◽  
Scott M. O'Grady

Human airway epithelial cells express β-adrenergic receptors (β-ARs), which regulate mucociliary clearance by stimulating transepithelial anion transport and ciliary beat frequency. Previous studies using airway epithelial cells showed that stimulation with isoproterenol increased cell migration and wound repair by a cAMP-dependent mechanism. In the present study, impedance-sensing arrays were used to measure cell migration and epithelial restitution following wounding of confluent normal human bronchial epithelial (NHBE) and Calu-3 cells by electroporation. Stimulation with epinephrine or the β2-AR-selective agonist salbutamol significantly delayed wound closure and reduced the mean surface area of lamellipodia protruding into the wound. Treatment with the β-AR bias agonist carvedilol or isoetharine also produced a delay in epithelial restitution similar in magnitude to epinephrine and salbutamol. Measurements of extracellular signal-regulated kinase phosphorylation following salbutamol or carvedilol stimulation showed no significant change in the level of phosphorylation compared with untreated control cells. However, inhibition of protein phosphatase 2A activity completely blocked the delay in wound closure produced by β-AR agonists. In Calu-3 cells, where CFTR expression was inhibited by RNAi, salbutamol did not inhibit wound repair, suggesting that β-AR agonist stimulation and loss of CFTR function share a common pathway leading to inhibition of epithelial repair. Confocal images of the basal membrane of Calu-3 cells labeled with anti-β1-integrin (clone HUTS-4) antibody showed that treatment with epinephrine or carvedilol reduced the level of activated integrin in the membrane. These findings suggest that treatment with β-AR agonists delays airway epithelial repair by a G protein- and cAMP-independent mechanism involving protein phosphatase 2A and a reduction in β1-integrin activation in the basal membrane.


1977 ◽  
Vol 55 (7) ◽  
pp. 1158-1165 ◽  
Author(s):  
Charles R. Bursey

Observations are presented on the wound repair process of the horseshoe crab, Limulus polyphemus. A cut, 1 × 40 × 3 mm, was made through the dorsal abdominal carapace and observations of the tissue at the wound site were made at 6, 24, 48, 96 h and 5, 10, 15, 30, 60, 90, 120, and 180 days. The wound was immediately plugged by a hemolymph coagulum and there was heavy infiltration of hemocytes into the area. Infiltrating hemocytes undergo a series of changes. The outermost cells hyalinize and form a thick layer between the cut ends of the exoskeleton. Pigmented epithelial cells migrate into the scar and produce a layer of cuticle under the cut exoskeleton. During the remaining period of observation, the cuticular scab enlarged and the cellular mass that filled the wound channel was lost through a series of changes that eventually restored the original tissue structure.


2014 ◽  
Vol 307 (2) ◽  
pp. L186-L196 ◽  
Author(s):  
April Kalinowski ◽  
Iris Ueki ◽  
Gundula Min-Oo ◽  
Eric Ballon-Landa ◽  
David Knoff ◽  
...  

Airway epithelial cells are the primary cell type involved in respiratory viral infection. Upon infection, airway epithelium plays a critical role in host defense against viral infection by contributing to innate and adaptive immune responses. Influenza A virus, rhinovirus, and respiratory syncytial virus (RSV) represent a broad range of human viral pathogens that cause viral pneumonia and induce exacerbations of asthma and chronic obstructive pulmonary disease. These respiratory viruses induce airway epithelial production of IL-8, which involves epidermal growth factor receptor (EGFR) activation. EGFR activation involves an integrated signaling pathway that includes NADPH oxidase activation of metalloproteinase, and EGFR proligand release that activates EGFR. Because respiratory viruses have been shown to activate EGFR via this signaling pathway in airway epithelium, we investigated the effect of virus-induced EGFR activation on airway epithelial antiviral responses. CXCL10, a chemokine produced by airway epithelial cells in response to respiratory viral infection, contributes to the recruitment of lymphocytes to target and kill virus-infected cells. While respiratory viruses activate EGFR, the interaction between CXCL10 and EGFR signaling pathways is unclear, and the potential for EGFR signaling to suppress CXCL10 has not been explored. Here, we report that respiratory virus-induced EGFR activation suppresses CXCL10 production. We found that influenza virus-, rhinovirus-, and RSV-induced EGFR activation suppressed IFN regulatory factor (IRF) 1-dependent CXCL10 production. In addition, inhibition of EGFR during viral infection augmented IRF1 and CXCL10. These findings describe a novel mechanism that viruses use to suppress endogenous antiviral defenses, and provide potential targets for future therapies.


2020 ◽  
Vol 26 (Supplement_1) ◽  
pp. S12-S12
Author(s):  
Dina Polosukhina ◽  
Kshipra Singh ◽  
Daniel Barry ◽  
Margaret Allaman ◽  
Maria Piazuelo ◽  
...  

Abstract Background We have shown that CCL11 (eotaxin-1), an eosinophil chemoattractant, is significantly increased in the serum of ulcerative colitis and Crohn’s disease patients vs controls and is also increased in dextran sulfate sodium (DSS)-induced murine colitis. In response to azoxymethane (AOM)-DSS, Ccl11–/– mice have significantly decreased colonic tumor number and burden, histologic injury, and colonic eosinophil infiltration vs wild-type (WT) mice. Ccl11 is expressed by isolated colonic epithelial and lamina propria immune cells. Studies in bone marrow chimera mice revealed that both hematopoietic- and epithelial-cell derived CCL11 were important for protection in the AOM-DSS model. Our aim was to assess the role of CCL11 in an injury and recovery colitis model and in an epithelial wound restitution model. Methods C57BL/6 WT and Ccl11–/– mice were exposed to 4% DSS in the drinking water for 5 days followed by 5 days of water for an injury and recovery model. Body weights were assessed daily. Histologic injury was assessed by a validated scoring system including depth and percent involvement of inflammation and crypt damage. Colonic eosinophil and neutrophil infiltration was determined by immunohistochemistry for major basic protein (MBP) and myeloperoxidase (MPO), respectively. The number of MBP- and MPO-positive cells per high-powered field (HPF) were quantified in a blinded manner. Young Adult Mouse Colon (YAMC) epithelial cells were stained with antibodies to the CCL11 receptors CCR2, CCR3, and CCR5 for assessment by flow cytometry. YAMC cell monolayers were wounded and followed for 24 h in normal media or with the addition of 100ng/mL recombinant CCL11 (rCCL11). The wound area was measured at 0 and 24 h to determine percent restitution. RNA was isolated and assessed for Ccl11 mRNA expression. Results In the injury and recovery model, Ccl11–/– mice exhibited decreased body weight loss (p&lt;0.05), histologic injury (20.6 ± 1.5 vs 12.4 ± 1.6, p&lt;0.001), and fewer MBP-positive cells/HPF (23.5 ± 1.4 vs 2.4 ± 0.2, p&lt;0.001) vs WT mice. While colonic MPO-positive cells were increased with DSS exposure, there was no difference in Ccl11–/– mice. Naïve/unstimulated YAMC cells expressed both CCR3 and CCR5. Wounding the YAMC monolayer alone did not lead to increased Ccl11 mRNA expression. However, in the presence of rCCL11, there was a decrease in wound restitution at 24 h (48.0% ± 1.7 vs 31.3% ± 2.1, p&lt;0.001). Conclusions Loss of CCL11 leads to clinical and histologic improvement in an injury and recovery colitis model. Colonic epithelial cells express both CCR3 and CCR5, and epithelial wound restitution is decreased in the presence of rCCL11. These data suggest that CCL11 has a deleterious effect on epithelial restitution leading to an exacerbation of colitis. Therefore, treatment with anti-CCL11 antibodies may be a therapeutic strategy in IBD patients.


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