Expression and functional implications of CCR2 expression on murine alveolar epithelial cells

Acute lung injury results in damage to the alveolar epithelium, leading to leak of proteins into the alveolar space and impaired gas exchange. Lung function can be restored only if the epithelial layer is restored. The process of reepithelialization requires migration of lung epithelial cells to cover denuded basement membranes. The factors that control the migration of lung epithelial cells are incompletely understood. We examined isolated murine type II alveolar epithelial cells (AECs) for expression of CC chemokine receptor 2 (CCR2) and functional consequences of the binding of the main CCR2 ligand monocyte chemoattractant protein-1 (MCP-1). We found that primary AECs bound MCP-1 and expressed CCR2 mRNA. These cells demonstrated functional consequences of CCR2 expression with migration in response to MCP-1 in chemotaxis/haptotaxis assays. Primary AECs cultured from mice lacking CCR2 did not respond to MCP-1. Monolayers of AECs lacking CCR2 demonstrated delayed closure of mechanical wounds compared with AEC monolayers expressing CCR2. Delayed closure of mechanical wounds of wild-type AECs was also demonstrated in the presence of anti-MCP-1 antibody. These data demonstrate for the first time that AECs express CCR2 and are capable of using this receptor for chemotaxis and healing of wounds. CCR2-MCP-1 interactions may be important in the process of reepithelialization after lung injury.

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Single-Cell Transcriptomics Identifies Dysregulated Metabolic Programs of Aging Alveolar Progenitor Cells in Lung Fibrosis

10.1101/2020.07.30.227892 ◽

2020 ◽

Author(s):

Jiurong Liang ◽

Guanling Huang ◽

Xue Liu ◽

Forough Taghavifar ◽

Ningshan Liu ◽

...

Keyword(s):

Lipid Metabolism ◽

Epithelial Cells ◽

Lung Injury ◽

Single Cell ◽

Cell Types ◽

Alveolar Epithelial Cells ◽

Lung Epithelial Cells ◽

Alveolar Epithelial ◽

Metabolic Defects ◽

Lung Epithelial

ABSTRACTAging is a critical risk factor in progressive lung fibrotic diseases such as idiopathic pulmonary fibrosis (IPF). Loss of integrity of type 2 alveolar epithelial cells (AEC2s) is the main causal event in the pathogenesis of IPF. To systematically examine the genomic program changes of AEC2s with aging and lung injury, we performed unbiased single cell RNA-seq analyses of lung epithelial cells from either uninjured or bleomycin-injured young and old mice. Major lung epithelial cell types were readily identified with canonical cell markers in our dataset. Heterogenecity of AEC2s was apparent, and AEC2s were then classified into three subsets according to their gene signatures. Genes related to lipid metabolism and glycolysis were significantly altered within these three clusters of AEC2s, and also affected by aging and lung injury. Importantly, IPF AEC2s showed similar genomic programming and metabolic changes as that of AEC2s from bleomycin injured old mouse lungs relative to controls. Furthermore, perturbation of both lipid metabolism and glycolysis significantly changed progenitor renewal capacity in 3-Demensional organoid culture of AEC2s. Taken togather, this work identified metabolic defects of AEC2s in aging and during lung injury. Strategies to rectify these altered programs would promote AEC2 renewal which in turn improves lung repair.One sentence summaryMetabolic defects of alveolar progenitors in aging and during lung injury impair their renewal.

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Time-resolved dual RNA-Seq reveals extensive rewiring of lung epithelial and pneumococcal transcriptomes during early infection

10.1101/048959 ◽

2016 ◽

Author(s):

Rieza Aprianto ◽

Jelle Slager ◽

Siger Holsappel ◽

Jan-Willem Veening

Keyword(s):

Epithelial Cells ◽

Pneumococcal Infection ◽

Alveolar Epithelial Cells ◽

Lung Epithelial Cells ◽

Infection Model ◽

Rna Seq ◽

Time Resolved ◽

Alveolar Epithelial ◽

Lung Epithelial ◽

Host Microbe Interactions

AbstractStreptococcus pneumoniae(pneumococcus) is the main etiological agent of pneumonia. Pneumococcal pneumonia is initiated by bacterial adherence to lung epithelial cells. Infection to the epithelium is a disruptive interspecies interaction involving numerous transcription-mediated processes. Revealing transcriptional changes may provide valuable insights into pneumococcal disease. Dual RNA-Seq allows simultaneous monitoring of the transcriptomes of both host and pathogen. Here, we developed a time-resolved infection model of human lung alveolar epithelial cells byS. pneumoniaeand assessed transcriptome changes by dual RNA-Seq. Our data provide new insights into host-microbe interactions and show that the epithelial glutathione-detoxification pathway is activated by bacterial presence. We observed that adherent pneumococci, not free-floating bacteria, access host-associated carbohydrates and repress innate immune responses. In conclusion, we provide a dynamic dual-transcriptomics overview of early pneumococcal infection with easy online access (http://dualrnaseq.molgenrug.nl). Further database exploration may expand our understanding of epithelial-pneumococcal interaction, leading to novel antimicrobial strategies.Graphical Abstract

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Resveratrol inhibits Staphylococcus aureus-induced TLR2/MyD88/NF-κB-dependent VCAM-1 expression in human lung epithelial cells

Clinical Science ◽

10.1042/cs20130816 ◽

2014 ◽

Vol 127 (6) ◽

pp. 375-390 ◽

Cited By ~ 14

Author(s):

I-Ta Lee ◽

Chih-Chung Lin ◽

Chih-Kai Hsu ◽

Ming-Yen Wu ◽

Rou-Ling Cho ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Epithelial Cells ◽

Human Lung ◽

Alveolar Epithelial Cells ◽

Lung Epithelial Cells ◽

Polyphenolic Compound ◽

Alveolar Epithelial ◽

Lung Epithelial ◽

Dependent Pathway ◽

Human Lung Epithelial Cells

In the present study, we found that S. aureus induced VCAM-1 expression in human pulmonary alveolar epithelial cells via a TLR2/MyD88/NF-κB-dependent pathway, which was inhibited by treatment with the polyphenolic compound resveratrol.

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Regulation of IL-33 by Oncostatin M in Mouse Lung Epithelial Cells

Mediators of Inflammation ◽

10.1155/2016/9858374 ◽

2016 ◽

Vol 2016 ◽

pp. 1-12 ◽

Cited By ~ 8

Author(s):

Carl D. Richards ◽

Laura Izakelian ◽

Anisha Dubey ◽

Grace Zhang ◽

Steven Wong ◽

...

Keyword(s):

Epithelial Cells ◽

Alveolar Epithelial Cells ◽

Lung Epithelial Cells ◽

Oncostatin M ◽

Mouse Lung ◽

Nuclear Staining ◽

Potent Inducer ◽

Alveolar Epithelial ◽

Lung Epithelial

IL-33 modulates both innate and adaptive immune responses at tissue sites including lung and may play critical roles in inflammatory lung disease. Although IL-33 expression can be altered upon NF-Kappa B activation, here we examine regulation by Oncostatin M, a gp130 cytokine family member, in mouse lung tissue. Responses were assessed in BALB/c mouse lung at day 7 of transient overexpression using endotracheally administered adenovirus encoding OSM (AdOSM) or empty vector (AdDel70). Whole lung extracts showed induction of IL-33 mRNA (>20-fold) and protein (10-fold increase in immunoblots) by AdOSM relative to AdDel70. Immunohistochemistry for IL-33 indicated a marked induction of nuclear staining in alveolar epithelial cellsin vivo. Oncostatin M stimulated IL-33 mRNA and IL-33 full length protein in C10 mouse type 2 alveolar epithelial cells in culture in time-dependent and dose-dependent fashion, whereas IL-6, LIF, IL-31, IL-4, or IL-13 did not, and TGFβrepressed IL-33. IL-33 induction was associated with activation of STAT3, and pharmacological inhibition of STAT3 ameliorated IL-33 levels. These results indicate Oncostatin M as a potent inducer of IL-33 in mouse lung epithelial cells and suggest that an OSM/IL-33 axis may participate in innate immunity and inflammatory conditions in lung.

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TRIM72 modulates caveolar endocytosis in repair of lung cells

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00089.2015 ◽

2016 ◽

Vol 310 (5) ◽

pp. L452-L464 ◽

Cited By ~ 11

Author(s):

Nagaraja Nagre ◽

Shaohua Wang ◽

Thomas Kellett ◽

Ragu Kanagasabai ◽

Jing Deng ◽

...

Keyword(s):

Plasma Membrane ◽

Epithelial Cells ◽

Cell Injury ◽

Alveolar Epithelial Cells ◽

Lung Epithelial Cells ◽

Functional Domain ◽

Physical Interaction ◽

Type I ◽

Alveolar Epithelial ◽

Lung Epithelial

Alveolar epithelial and endothelial cell injury is a major feature of the acute respiratory distress syndrome, in particular when in conjunction with ventilation therapies. Previously we showed [Kim SC, Kellett T, Wang S, Nishi M, Nagre N, Zhou B, Flodby P, Shilo K, Ghadiali SN, Takeshima H, Hubmayr RD, Zhao X. Am J Physiol Lung Cell Mol Physiol 307: L449–L459, 2014.] that tripartite motif protein 72 (TRIM72) is essential for amending alveolar epithelial cell injury. Here, we posit that TRIM72 improves cellular integrity through its interaction with caveolin 1 (Cav1). Our data show that, in primary type I alveolar epithelial cells, lack of TRIM72 led to significant reduction of Cav1 at the plasma membrane, accompanied by marked attenuation of caveolar endocytosis. Meanwhile, lentivirus-mediated overexpression of TRIM72 selectively increases caveolar endocytosis in rat lung epithelial cells, suggesting a functional association between these two. Further coimmunoprecipitation assays show that deletion of either functional domain of TRIM72, i.e., RING, B-box, coiled-coil, or PRY-SPRY, abolishes the physical interaction between TRIM72 and Cav1, suggesting that all theoretical domains of TRIM72 are required to forge a strong interaction between these two molecules. Moreover, in vivo studies showed that injurious ventilation-induced lung cell death was significantly increased in knockout (KO) TRIM72KO and Cav1KO lungs compared with wild-type controls and was particularly pronounced in double KO mutants. Apoptosis was accompanied by accentuation of gross lung injury manifestations in the TRIM72KO and Cav1KO mice. Our data show that TRIM72 directly and indirectly modulates caveolar endocytosis, an essential process involved in repair of lung epithelial cells through removal of plasma membrane wounds. Given TRIM72's role in endomembrane trafficking and cell repair, we consider this molecule an attractive therapeutic target for patients with injured lungs.

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Modulation of sodium transport in fetal alveolar epithelial cells by oxygen and corticosterone

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00218.2002 ◽

2003 ◽

Vol 284 (2) ◽

pp. L376-L385 ◽

Cited By ~ 39

Author(s):

Ulrich H. Thome ◽

Ian C. Davis ◽

Susie Vo Nguyen ◽

Brent Jay Shelton ◽

Sadis Matalon

Keyword(s):

Epithelial Cells ◽

Short Circuit ◽

Alveolar Epithelial Cells ◽

Lung Epithelial Cells ◽

Ussing Chambers ◽

Alveolar Epithelial ◽

Lung Epithelial ◽

Distal Lung ◽

Postnatal Adaptation ◽

Short Circuit Currents

Regulation of active Na+transport across fetal distal lung epithelial cells (FDLE) by corticosterone (CST), corticotropin-releasing hormone (CRH), and oxygen tension may be crucial for postnatal adaptation. FDLE isolated from 19-day rat fetuses (term: 22 days) were grown on permeable supports to confluent monolayers (duration 3 days) in 2.5, 5, 12, or 20% O2 with 5% CO2-balance N2 and mounted in Ussing chambers for measurement of short-circuit currents ( I sc). FDLE monolayers grown in 20% O2 had significantly higher levels of total I sc and of their amiloride-sensitive ( I amil) and ouabain-sensitive ( I ouab) components than hypoxic cells. Values (μA/cm2 ± SE) for 2.5–5% O2 and 20% O2 were, respectively, I sc5.3 ± 0.2 vs. 8.4 ± 0.3 ( P < 0.001), I amil 3.4 ± 0.2 vs. 4.3 ± 0.2 ( P < 0.01), and I ouab 3.4 ± 0.6 vs. 9.1 ± 0.6 ( P < 0.001). Addition of CST but not CRH to the culture medium at any O2concentration increased I amil. FDLE cells grown at 5% O2 expressed significantly lower levels of α-, β-, and γ-epithelial Na+ channel (ENaC), and of the α1-Na+-K+-ATPase, as determined by Western blotting. We conclude that higher O2concentrations increased total vectorial Na+ transport, and the function of Na+-K+-ATPase and apical amiloride-sensitive Na+ conductance, whereas CST only increased ENaC function.

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Senescence associated long non-coding RNA 1 regulates cigarette smoke-induced senescence of type II alveolar epithelial cells through sirtuin-1 signaling

Journal of International Medical Research ◽

10.1177/0300060520986049 ◽

2021 ◽

Vol 49 (2) ◽

pp. 030006052098604

Author(s):

Dong Yuan ◽

Yuanshun Liu ◽

Mengyu Li ◽

Hongbin Zhou ◽

Liming Cao ◽

...

Keyword(s):

Epithelial Cells ◽

Cigarette Smoke ◽

Alveolar Epithelial Cell ◽

Alveolar Epithelial Cells ◽

Lung Epithelial Cells ◽

Sirtuin 1 ◽

Type Ii ◽

Alveolar Epithelial ◽

Non Coding Rna ◽

Long Non Coding Rna

Objective The primary aim of our study was to explore the mechanisms through which long non-coding RNA (lncRNA)-mediated sirtuin-1 (SIRT1) signaling regulates type II alveolar epithelial cell (AECII) senescence induced by a cigarette smoke-media suspension (CSM). Methods Pharmacological SIRT1 activation was induced using SRT2104 and senescence-associated lncRNA 1 (SAL-RNA1) was overexpressed. The expression of SIRT1, FOXO3a, p53, p21, MMP-9, and TIMP-1 in different groups was detected by qRT-PCR and Western blotting; the activity of SA-β gal was detected by staining; the binding of SIRT1 to FOXO3a and p53 gene transcription promoters was detected by Chip. Results We found that CSM increased AECII senescence, while SAL-RNA1 overexpression and SIRT1 activation significantly decreased levels of AECII senescence induced by CSM. Using chromatin immunoprecipitation, we found that SIRT1 bound differentially to transcriptional complexes on the FOXO3a and p53 promoters. Conclusion Our results suggested that lncRNA-SAL1-mediated SIRT1 signaling reduces senescence of AECIIs induced by CSM. These findings suggest a new therapeutic target to limit the irreversible apoptosis of lung epithelial cells in COPD patients.

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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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Fluid transport across cultured rat alveolar epithelial cells: a novel in vitro system

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00176.2003 ◽

2004 ◽

Vol 287 (1) ◽

pp. L104-L110 ◽

Cited By ~ 26

Author(s):

Xiaohui Fang ◽

Yuanlin Song ◽

Rachel Zemans ◽

Jan Hirsch ◽

Michael A. Matthay

Keyword(s):

Epithelial Cells ◽

Fluid Transport ◽

Alveolar Epithelial Cells ◽

Lung Epithelial Cells ◽

Morphological Evidence ◽

Alveolar Type ◽

Type Ii ◽

In Vitro System ◽

Alveolar Epithelial

Previous studies have used fluid-instilled lungs to measure net alveolar fluid transport in intact animal and human lungs. However, intact lung studies have two limitations: the contribution of different distal lung epithelial cells cannot be studied separately, and the surface area for fluid absorption can only be approximated. Therefore, we developed a method to measure net vectorial fluid transport in cultured rat alveolar type II cells using an air-liquid interface. The cells were seeded on 0.4-μm microporous inserts in a Transwell system. At 96 h, the transmembrane electrical resistance reached a peak level (1,530 ± 115 Ω·cm2) with morphological evidence of tight junctions. We measured net fluid transport by placing 150 μl of culture medium containing 0.5 μCi of 131I-albumin on the apical side of the polarized cells. Protein permeability across the cell monolayer, as measured by labeled albumin, was 1.17 ± 0.34% over 24 h. The change in concentration of 131I-albumin in the apical fluid was used to determine the net fluid transported across the monolayer over 12 and 24 h. The net basal fluid transport was 0.84 μl·cm−2·h−1. cAMP stimulation with forskolin and IBMX increased fluid transport by 96%. Amiloride inhibited both the basal and stimulated fluid transport. Ouabain inhibited basal fluid transport by 93%. The cultured cells retained alveolar type II-like features based on morphologic studies, including ultrastructural imaging. In conclusion, this novel in vitro system can be used to measure net vectorial fluid transport across cultured, polarized alveolar epithelial cells.

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