Virulence of an emerging respiratory pathogen, genus Pandoraea, in vivo and its interactions with lung epithelial cells

Pandoraea species have emerged as opportunistic pathogens among cystic fibrosis (CF) and non-CF patients. Pandoraea pulmonicola is the predominant Pandoraea species among Irish CF patients. The objective of this study was to investigate the pathogenicity and potential mechanisms of virulence of Irish P. pulmonicola isolates and strains from other Pandoraea species. Three patients from whom the P. pulmonicola isolates were isolated have since died. The in vivo virulence of these and other Pandoraea strains was examined by determining the ability to kill Galleria mellonella larvae. The P. pulmonicola strains generally were the most virulent of the species tested, with three showing a comparable or greater level of virulence in vivo relative to another CF pathogen, Burkholderia cenocepacia, whilst strains from two other species, Pandoraea apista and Pandoraea pnomenusa, were considerably less virulent. For all Pandoraea species, whole cells were required for larval killing, as cell-free supernatants had little effect on larval survival. Overall, invasive Pandoraea strains showed comparable invasion of two independent lung epithelial cell lines, irrespective of whether they had a CF phenotype. Pandoraea strains were also capable of translocation across polarized lung epithelial cell monolayers. Although protease secretion was a common characteristic across the genus, it is unlikely to be involved in pathogenesis. In conclusion, whilst multiple mechanisms of pathogenicity may exist across the genus Pandoraea, it appears that lung cell invasion and translocation contribute to the virulence of P. pulmonicola strains.

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Transgenic models for study of pulmonary development and disease

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.1994.267.5.l489 ◽

1994 ◽

Vol 267 (5) ◽

pp. L489-L497 ◽

Cited By ~ 12

Author(s):

S. W. Glasser ◽

T. R. Korfhagen ◽

S. E. Wert ◽

J. A. Whitsett

Keyword(s):

Epithelial Cell ◽

Animal Models ◽

Gene Targeting ◽

Transgenic Mouse ◽

Embryonic Stem ◽

Lung Epithelial Cell ◽

Major Advance ◽

Cis Acting ◽

Lung Epithelial

This review summarizes progress in the application of transgenic mouse technology to the study of lung development and disease. Since advances in molecular genetics have greatly facilitated the isolation of cDNA and genes, our ability to readily assess roles of both normal and mutated genes in transgenic mouse in vivo represents a major advance, bridging molecular biology and whole animal physiology. Strategies have been developed in which lung epithelial cell promoter elements are used to drive normal or mutated genes into specific subsets of respiratory epithelial cells in the lungs of developing and mature transgenic mice. These mice have been used to elucidate the cis-acting elements controlling lung epithelial cell gene expression, to discern the role of specific polypeptides in lung morphogenesis and tumorigenesis, and to create animal models of pulmonary disease. The ability to mutate genes at their precise chromosomal locations through gene targeting in embryonic stem cells has lead to the production of animal models of lung diseases such as cystic fibrosis. Both gene insertion and gene targeting create permanent mouse lines that pass the modified gene to their progeny, providing animals for the study of the pathogenesis and treatment of pulmonary disorders.

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Regulated in Development and DNA Damage Response 1 Knockdown Alleviates Lipopolysaccharide-Induced Acute Lung Injury

Journal of Biomaterials and Tissue Engineering ◽

10.1166/jbt.2021.2691 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1333-1338

Author(s):

Han Han ◽

Zhenxi Yu ◽

Mei Feng

Keyword(s):

Acute Lung Injury ◽

Epithelial Cell ◽

Epithelial Cells ◽

Lung Injury ◽

Cell Activity ◽

Lung Epithelial Cells ◽

Lung Epithelial Cell ◽

Inflammatory Factors ◽

Lung Epithelial ◽

Damage Response

Regulated in Development and DNA Damage Response 1 (REDD1) knockdown can reduce the endoplasmic reticulum stress response in liver injury. However, its role on lipopolysaccharide (LPS)-induced acute lung injury (ALI) has not been explored. This study aimed to evaluate the effect of REDD1 on lung epithelial cells induced by LPS. Rt-qPCR and Western blot were used to detect REDD1 expression in 16HBE cells induced by LPS. The interfering REDD1 plasmid was constructed, and CCK8 was used to detect the effect of interference with REDD1 on LPS-induced lung epithelial cell activity. The expression of inflammatory factors was detected by ELISA and the apoptotic level was detected by TUNEL staining. String database was used to predict the combination of REDD1 and EP300 in lung epithelial cells, which was verified by CoIP experiment. An overexpressed plasmid of EP300 was constructed to detect the effects of EP300 on inflammatory factors and apoptosis in REDD1 lung epithelial cells. LPS-induced increased REDD1 expression in lung epithelial cells. Interference with REDD1 inhibits LPS-induced lung epithelial cell activity injury and inflammatory factor expression and inhibits LPS-induced lung epithelial cell apoptosis. After interference with REDD1, the expression of EP300 in LPS-induced lung epithelial cells was inhibited, and the overexpression of EP300 was reversed to promote the production of inflammatory factors and apoptosis. In conclusion, these results demonstrate that REDD1 knockdown alleviates LPS-induced acute lung injury.

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FRA-1 Proto-Oncogene Induces Lung Epithelial Cell Invasion and Anchorage-Independent Growth In vitro, but Is Insufficient to Promote Tumor Growth In vivo

Cancer Research ◽

10.1158/0008-5472.can-06-4687 ◽

2007 ◽

Vol 67 (13) ◽

pp. 6204-6211 ◽

Cited By ~ 52

Author(s):

Pavan Adiseshaiah ◽

Daniel J. Lindner ◽

Dhananjaya V. Kalvakolanu ◽

Sekhar P. Reddy

Keyword(s):

Epithelial Cell ◽

Tumor Growth ◽

Cell Invasion ◽

Lung Epithelial Cell ◽

Anchorage Independent Growth ◽

Promote Tumor Growth ◽

Lung Epithelial ◽

Epithelial Cell Invasion

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CCN1 secretion and cleavage regulate the lung epithelial cell functions after cigarette smoke

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00102.2014 ◽

2014 ◽

Vol 307 (4) ◽

pp. L326-L337 ◽

Cited By ~ 47

Author(s):

Hyung-Geun Moon ◽

Sang-Heon Kim ◽

Jinming Gao ◽

Taihao Quan ◽

Zhaoping Qin ◽

...

Keyword(s):

Epithelial Cell ◽

Cigarette Smoke ◽

Prolonged Exposure ◽

Cell Damage ◽

Lung Epithelial Cells ◽

Tissue Loss ◽

Cell Functions ◽

Lung Epithelial

Despite extensive research, the pathogenesis of cigarette smoking (CS)-associated emphysema remains incompletely understood, thereby impeding development of novel therapeutics, diagnostics, and biomarkers. Here, we report a novel paradigm potentially involved in the development of epithelial death and tissue loss in CS-associated emphysema. After prolonged exposure of CS, CCN1 cleavage was detected both in vitro and in vivo. Full-length CCN1 (flCCN1) was secreted in an exosome-shuttled manner, and secreted plasmin converted flCCN1 to cleaved CCN1 (cCCN1) in extracellular matrix. Interestingly, exosome-shuttled flCCN1 facilitated the interleukin (IL)-8 and vascular endothelial growth factor (VEGF) release in response to cigarette smoke extract (CSE). Therefore, flCCN1 potentially promoted CS-induced inflammation via IL-8-mediated neutrophil recruitment and also maintained the lung homeostasis via VEGF secretion. Interestingly, cCCN1 abolished these functions. Furthermore, cCCN1 promoted protease and matrix metalloproteinase (MMP)-1 production after CSE. These effects were mainly mediated by the COOH-terminal fragments of CCN1 after cleavage. Both the decrease of VEGF and the elevation of MMPs favor the development of emphysema. cCCN1, therefore, likely contributes to the epithelial cell damage after CS. Additionally, CSE and cCCN1 both stimulated integrin-α7 expressions in lung epithelial cells. The integrin-α7 appeared to be the binding receptors of cCCN1 and, subsequently, mediated its cellular function by promoting MMP1. Consistent with our observation on the functional roles of cCCN1 in vitro, elevated cCCN1 level was found in the bronchoalveolar lavage fluid from mice with emphysematous changes after 6 mo CS exposure. Taken together, we hypothesize that cCCN1 promoted the epithelial cell death and tissue loss after prolonged CS exposure.

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Integrin Alpha6Beta4 Identifies An Adult Distal Lung Epithelial Cell Population With Progenitor Potential In Vivo

10.1164/ajrccm-conference.2011.183.1_meetingabstracts.a1242 ◽

2011 ◽

Author(s):

xiaopeng Li ◽

Alexis Brumwell ◽

Walter Lorizio ◽

Janet Chen ◽

Ying Wei ◽

...

Keyword(s):

Epithelial Cell ◽

Cell Population ◽

Lung Epithelial Cell ◽

Integrin Alpha6beta4 ◽

Lung Epithelial ◽

Distal Lung ◽

Epithelial Cell Population

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TNF Family Cytokines Induce Distinct Cell Death Modalities in the A549 Human Lung Epithelial Cell Line when Administered in Combination with Ricin Toxin

Toxins ◽

10.3390/toxins11080450 ◽

2019 ◽

Vol 11 (8) ◽

pp. 450 ◽

Cited By ~ 5

Author(s):

Hodges ◽

Kempen ◽

McCaig ◽

Parker ◽

Mantis ◽

...

Keyword(s):

Cell Death ◽

Epithelial Cell ◽

Epithelial Cells ◽

Human Lung ◽

Lung Epithelial Cells ◽

Lung Epithelial Cell ◽

Distinct Cell ◽

Tnf Α ◽

Lung Epithelial ◽

Human Lung Epithelial Cells

Ricin is a member of the ribosome-inactivating protein (RIP) family of toxins and is classified as a biothreat agent by the Centers for Disease Control and Prevention (CDC). Inhalation, the most potent route of toxicity, triggers an acute respiratory distress-like syndrome that coincides with near complete destruction of the lung epithelium. We previously demonstrated that the TNF-related apoptosis-inducing ligand (TRAIL; CD253) sensitizes human lung epithelial cells to ricin-induced death. Here, we report that ricin/TRAIL-mediated cell death occurs via apoptosis and involves caspases -3, -7, -8, and -9, but not caspase-6. In addition, we show that two other TNF family members, TNF-α and Fas ligand (FasL), also sensitize human lung epithelial cells to ricin-induced death. While ricin/TNF-α- and ricin/FasL-mediated killing of A549 cells was inhibited by the pan-caspase inhibitor, zVAD-fmk, evidence suggests that these pathways were not caspase-dependent apoptosis. We also ruled out necroptosis and pyroptosis. Rather, the combination of ricin plus TNF-α or FasL induced cathepsin-dependent cell death, as evidenced by the use of several pharmacologic inhibitors. We postulate that the effects of zVAD-fmk were due to the molecule’s known off-target effects on cathepsin activity. This work demonstrates that ricin-induced lung epithelial cell killing occurs by distinct cell death pathways dependent on the presence of different sensitizing cytokines, TRAIL, TNF-α, or FasL.

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Lung epithelial cell-derived extracellular vesicles activate macrophage-mediated inflammatory responses via ROCK1 pathway

Cell Death and Disease ◽

10.1038/cddis.2015.282 ◽

2015 ◽

Vol 6 (12) ◽

pp. e2016-e2016 ◽

Cited By ~ 49

Author(s):

H-G Moon ◽

Y Cao ◽

J Yang ◽

J H Lee ◽

H S Choi ◽

...

Keyword(s):

Epithelial Cell ◽

Epithelial Cells ◽

Extracellular Vesicles ◽

Caspase 3 ◽

Inflammatory Responses ◽

Lung Epithelial Cells ◽

Lung Epithelial Cell ◽

Apoptotic Bodies ◽

Protein Markers ◽

Lung Epithelial

Abstract Despite decades of research, the pathogenesis of acute respiratory distress syndrome (ARDS) remains poorly understood, thus impeding the development of effective treatment. Diffuse alveolar damage (DAD) and lung epithelial cell death are prominent features of ARDS. Lung epithelial cells are the first line of defense after inhaled stimuli, such as in the case of hyperoxia. We hypothesized that lung epithelial cells release ‘messenger’ or signaling molecules to adjacent or distant macrophages, thereby initiating or propagating inflammatory responses after noxious insult. We found that, after hyperoxia, a large amount of extracellular vesicles (EVs) were generated and released into bronchoalveolar lavage fluid (BALF). These hyperoxia-induced EVs were mainly derived from live lung epithelial cells as the result of hyperoxia-associated endoplasmic reticulum (ER) stress. These EVs were remarkably different from epithelial ‘apoptotic bodies’, as reflected by the significantly smaller size and differentially expressed protein markers. These EVs fall mainly in the size range of the exosomes and smaller microvesicles (MVs) (50–120 nm). The commonly featured protein markers of apoptotic bodies were not found in these EVs. Treating alveolar macrophages with hyperoxia-induced, epithelial cell-derived EVs led to an increased secretion of pro-inflammatory cytokines and macrophage inflammatory protein 2 (MIP-2). Robustly increased macrophage and neutrophil influx was found in the lung tissue of the mice intranasally treated with hyperoxia-induced EVs. It was determined that EV-encapsulated caspase-3 was largely responsible for the alveolar macrophage activation via the ROCK1 pathway. Caspase-3-deficient EVs induced less cytokine/MIP-2 release, reduced cell counts in BALF, less neutrophil infiltration and less inflammation in lung parenchyma, both in vitro and in vivo. Furthermore, the serum circulating EVs were increased and mainly derived from lung epithelial cells after hyperoxia exposure. These circulating EVs also activated systemic macrophages other than the alveolar ones. Collectively, the results show that hyperoxia-induced, lung epithelial cell-derived and caspase-3 enriched EVs activate macrophages and mediate the inflammatory lung responses involved in lung injury.

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The fibrinolytic system and the regulation of lung epithelial cell proteolysis, signaling, and cellular viability

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.90349.2008 ◽

2008 ◽

Vol 295 (6) ◽

pp. L967-L975 ◽

Cited By ~ 46

Author(s):

Sreerama Shetty ◽

Joseph Padijnayayveetil ◽

Torry Tucker ◽

Dorota Stankowska ◽

Steven Idell

Keyword(s):

Epithelial Cell ◽

Epithelial Cells ◽

Plasminogen Activator ◽

Mrna Stability ◽

Fibrinolytic System ◽

Lung Epithelial Cells ◽

Lung Epithelial Cell ◽

Plasminogen Activator Inhibitor 1 ◽

Lung Epithelial ◽

Pai 1

The urokinase-type plasminogen activator (uPA), its receptor (uPAR), and plasminogen activator inhibitor-1 (PAI-1) are key components of the fibrinolytic system and are expressed by lung epithelial cells. uPA, uPAR, and PAI-1 have been strongly implicated in the pathogenesis of acute lung injury (ALI) and pulmonary fibrosis. Recently, it has become clear that regulation of uPA, uPAR, and PAI-1 occurs at the posttranscriptional level of mRNA stability in lung epithelial cells. uPA further mediates its own expression in these cells as well as that of uPAR and PAI-1 through induction of changes in mRNA stability. In addition, uPA-mediated signaling controls the expression of the tumor suppressor protein p53 in lung epithelial cells at the posttranslational level. p53 has recently been shown to be a trans-acting uPA, uPAR, and PAI-1 mRNA-binding protein that regulates the stability of these mRNAs. It is now clear that signaling initiated by uPA mediates dose-dependent regulation of lung epithelial cell apoptosis and likewise involves changes in p53, uPA, uPAR, and PAI-1 expression. These findings demonstrate that the uPA-uPAR-PAI-1 system of lung epithelial cells mediates a broad repertoire of responses that encompass but extend well beyond traditional fibrinolysis, involve newly recognized interactions with p53 that influence the viability of the lung epithelium, and are thereby implicated in the pathogenesis of ALI and its repair.

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Effect of curcumin on lung epithelial injury and ferroptosis induced by cigarette smoke

Human & Experimental Toxicology ◽

10.1177/09603271211059497 ◽

2021 ◽

pp. 096032712110594

Author(s):

Xin Tang ◽

Zhenyu Li ◽

Zhi Yu ◽

Jinna Li ◽

Jinbang Zhang ◽

...

Keyword(s):

Epithelial Cell ◽

Cigarette Smoke ◽

Cell Injury ◽

Lavage Fluid ◽

Lung Epithelial Cell ◽

Control Group ◽

Epithelial Injury ◽

Lung Epithelial

Cigarette smoke (CS)-caused ferroptosis was involved in the pathogenesis of COPD, but the role of ferroptosis in lung epithelial injury and inflammation is not clear. Rats were treated with CS or CUR and BEAS-2B cells were exposed to CS extract (CSE), ferrostatin-1 (Fer-1), deferoxamine (DFO), or CUR to detect reactive oxygen species (ROS) accumulation, lipid peroxidation, iron overload, and ferroptosis-related protein, which were the characteristic changes of ferroptosis. Compared with the control group, CSE-treated BEAS-2B cells had more cell death, higher cytotoxicity, and lower cell viability. The infiltration of inflammatory cell around the bronchi in the CS group of rats was more than that in the normal group. Meanwhile, CSE/CS elevated the levels of interleukin-6 and tumor necrosis factor-α in BEAS-2B cells and bronchoalveolar lavage fluid of rats. Besides, accumulative ROS and depleted glutathione was observed in vitro. In BEAS-2B cells and lung tissues of rats, CSE/CS increased malondialdehyde and iron; down-regulated solute carrier family 7, glutathione peroxidase 4, and ferritin heavy chain levels; and up-regulated transferrin receptor level. These changes were rescued by pretreatment of Fer-1 or DFO in vitro, and mitigated by CUR in vitro and in vivo. Collectively, this study reveals that ferroptosis was involved in lung epithelial cell injury and inflammation induced by CS, and CUR may alleviate CS-induced injury, inflammation, and ferroptosis of lung epithelial cell.

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