scholarly journals Second-generation lung-on-a-chip with an array of stretchable alveoli made with a biological membrane

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Pauline Zamprogno ◽  
Simon Wüthrich ◽  
Sven Achenbach ◽  
Giuditta Thoma ◽  
Janick D. Stucki ◽  
...  
Keyword(s):  
Alveolar Epithelial Cell ◽  
Biological Membrane ◽  
Dynamic Environment ◽  
Basal Membrane ◽  
Barrier Properties ◽  
Alveolar Epithelial Cells ◽  
Simple Method ◽  
Alveolar Epithelial

AbstractThe air-blood barrier with its complex architecture and dynamic environment is difficult to mimic in vitro. Lung-on-a-chips enable mimicking the breathing movements using a thin, stretchable PDMS membrane. However, they fail to reproduce the characteristic alveoli network as well as the biochemical and physical properties of the alveolar basal membrane. Here, we present a lung-on-a-chip, based on a biological, stretchable and biodegradable membrane made of collagen and elastin, that emulates an array of tiny alveoli with in vivo-like dimensions. This membrane outperforms PDMS in many ways: it does not absorb rhodamine-B, is biodegradable, is created by a simple method, and can easily be tuned to modify its thickness, composition and stiffness. The air-blood barrier is reconstituted using primary lung alveolar epithelial cells from patients and primary lung endothelial cells. Typical alveolar epithelial cell markers are expressed, while the barrier properties are preserved for up to 3 weeks.

scholarly journals Second-generation lung-on-a-chip array with a stretchable biological membrane

2019 ◽  
Author(s):  
Pauline Zamprogno ◽  
Simon Wüthrich ◽  
Sven Achenbach ◽  
Janick D. Stucki ◽  
Nina Hobi ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Second Generation ◽  
Biological Membrane ◽  
Barrier Properties ◽  
Lung Parenchyma ◽  
Alveolar Epithelial Cells ◽  
Pdms Membrane ◽  
Alveolar Epithelial

AbstractThe complex architecture of the lung parenchyma and the air-blood barrier is difficult to mimic in-vitro. Recently reported lung-on-a-chips used a thin, porous and stretchable PDMS membrane, to mimic the air-blood barrier and the rhythmic breathing motions. However, the nature, the properties and the size of this PDMS membrane differ from the extracellular matrix of the distal airways. Here, we present a second-generation lung-on-a-chip with an array of in vivo-like sized alveoli and a stretchable biological membrane. This nearly absorption free membrane allows mimicking in vivo functionality of the lung parenchyma at an unprecedented level. The air-blood barrier is constituted by human primary lung alveolar epithelial cells from several patients and co-cultured with primary lung endothelial cells. Typical markers of lung alveolar epithelial cells could be observed in the model, while barrier properties were preserved for up to three weeks. This advanced lung alveolar model reproduces some key features of the lung alveolar environment in terms of composition, alveolar size, mechanical forces and biological functions, which makes this model a more analogous tool for drug discovery, diseases modeling and precision medicine applications.

scholarly journals TRIM72 is required for effective repair of alveolar epithelial cell wounding

2014 ◽  
Vol 307 (6) ◽  
pp. L449-L459 ◽  
Author(s):  
Seong Chul Kim ◽  
Thomas Kellett ◽  
Shaohua Wang ◽  
Miyuki Nishi ◽  
Nagaraja Nagre ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Molecular Mechanisms ◽  
Striated Muscle ◽  
Alveolar Epithelial Cell ◽  
Alveolar Epithelial Cells ◽  
Lung Cells ◽  
Alveolar Epithelial ◽  
High Tidal Volume Ventilation

The molecular mechanisms for lung cell repair are largely unknown. Previous studies identified tripartite motif protein 72 (TRIM72) from striated muscle and linked its function to tissue repair. In this study, we characterized TRIM72 expression in lung tissues and investigated the role of TRIM72 in repair of alveolar epithelial cells. In vivo injury of lung cells was introduced by high tidal volume ventilation, and repair-defective cells were labeled with postinjury administration of propidium iodide. Primary alveolar epithelial cells were isolated and membrane wounding and repair were labeled separately. Our results show that absence of TRIM72 increases susceptibility to deformation-induced lung injury whereas TRIM72 overexpression is protective. In vitro cell wounding assay revealed that TRIM72 protects alveolar epithelial cells through promoting repair rather than increasing resistance to injury. The repair function of TRIM72 in lung cells is further linked to caveolin 1. These data suggest an essential role for TRIM72 in repair of alveolar epithelial cells under plasma membrane stress failure.

scholarly journals Pneumocystis Pneumonia Increases the Susceptibility of Mice to Sublethal Hyperoxia

2003 ◽  
Vol 71 (10) ◽  
pp. 5970-5978 ◽  
Author(s):  
James M. Beck ◽  
Angela M. Preston ◽  
Steven E. Wilcoxen ◽  
Susan B. Morris ◽  
Eric S. White ◽  
...  
Keyword(s):  
T Cells ◽  
Epithelial Cell ◽  
Cell Injury ◽  
Alveolar Epithelial Cell ◽  
Pulmonary Inflammation ◽  
Alveolar Epithelial Cells ◽  
Alveolar Epithelial ◽  
Epithelial Cell Injury

ABSTRACT Patients with Pneumocystis pneumonia often develop respiratory failure after entry into medical care, and one mechanism for this deterioration may be increased alveolar epithelial cell injury. In vitro, we previously demonstrated that Pneumocystis is not cytotoxic for alveolar epithelial cells. In vivo, however, infection with Pneumocystis could increase susceptibility to injury by stressors that, alone, would be sublethal. We examined transient exposure to hyperoxia as a prototypical stress that does cause mortality in normal mice. Mice were depleted of CD4+ T cells and inoculated intratracheally with Pneumocystis. Control mice were depleted of CD4+ T cells but did not receive Pneumocystis. After 4 weeks, mice were maintained in normoxia, were exposed to hyperoxia for 4 days, or were exposed to hyperoxia for 4 days followed by return to normoxia. CD4-depleted mice with Pneumocystis pneumonia demonstrated significant mortality after transient exposure to hyperoxia, while all uninfected control mice survived this stress. We determined that organism burdens were not different. However, infected mice exposed to hyperoxia and then returned to normoxia demonstrated significant increases in inflammatory cell accumulation and lung cell apoptosis. We conclude that Pneumocystis pneumonia leads to increased mortality following a normally sublethal hyperoxic insult, accompanied by alveolar epithelial cell injury and increased pulmonary inflammation.

scholarly journals Cross-talk between LAM cells and fibroblasts may influence alveolar epithelial cell behavior in Lymphangioleiomyomatosis

2021 ◽  
Author(s):  
Debbie Clements ◽  
Suzanne Miller ◽  
Roya Babaei-Jadidi ◽  
Mike Adam ◽  
S. Steven Potter ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Cross Talk ◽  
Ex Vivo ◽  
Alveolar Epithelial Cell ◽  
Alveolar Epithelial Cells ◽  
Dependent Manner ◽  
Epithelial Migration ◽  
Alveolar Epithelial

Lymphangioleiomyomatosis (LAM) is a female specific cystic lung disease in which TSC2 deficient LAM cells, LAM-Associated Fibroblasts (LAFs) and other cell types infiltrate the lungs. LAM lesions can be associated with type II alveolar epithelial cells (AT2 cells). We hypothesised that the behaviour of AT2 cells in LAM is influenced locally by LAFs. We tested this hypothesis in patient samples and in vitro. In human LAM lung, nodular AT2 cells show enhanced proliferation when compared to parenchymal AT2 cells, demonstrated by increased Ki67 expression. Further, nodular AT2 cells express proteins associated with epithelial activation in other disease states including Matrix Metalloproteinase 7, and Fibroblast Growth Factor 7 (FGF7). In vitro, LAF conditioned medium is mitogenic and positively chemotactic for epithelial cells, increases the rate of epithelial repair and protects against apoptosis. In vitro, LAM patient-derived TSC2 null cells cocultured with LAFs upregulate LAF expression of the epithelial chemokine and mitogen FGF7, which is a potential mediator of fibroblast-epithelial crosstalk, in an mTOR dependent manner. In a novel in vitro model of LAM, ex vivo cultured LAM lung-derived microtissues promote both epithelial migration and adhesion. Our findings suggest that AT2 cells in LAM display a proliferative, activated phenotype and that fibroblast accumulation following LAM cell infiltration into the parenchyma contributes to this change in AT2 cell behaviour. Fibroblast-derived FGF7 may contribute to the cross-talk between LAFs and hyperplastic epithelium in vivo, but does not appear to be the main driver of the effects of LAFs on epithelial cells in vitro.

Migration and gelatinases in cultured fetal, adult, and hyperoxic alveolar epithelial cells

2001 ◽  
Vol 281 (2) ◽  
pp. L427-L434 ◽  
Author(s):  
S. Buckley ◽  
B. Driscoll ◽  
W. Shi ◽  
K. Anderson ◽  
D. Warburton
Keyword(s):  
Growth Factor ◽  
Lung Development ◽  
Alveolar Epithelial Cell ◽  
Lung Cancer Cell Line ◽  
Alveolar Epithelial Cells ◽  
Migratory Activity ◽  
Alveolar Epithelial ◽  
Control Adult

Alveolar epithelial cell (AEC) migration mediated by matrix metalloproteinases (MMPs) is required for lung development and repair after injury such as hyperoxia. Of specific interest in lung remodeling are the gelatinases, which are upregulated in AEC after hyperoxia. We correlated migration and gelatinase production in AEC cultured from fetal, adult, and hyperoxic rats. Fetal AEC (19–20 days) had higher MMP-2 and MMP-9 gelatinase expression than adult AEC, with fivefold higher MMP-9 activity, and were migratory through gelatin, responding to epidermal growth factor, keratinocyte growth factor, and fibroblast growth factor-10. MMP-2 and MMP-9 expression and migratory activity could be detected from the time of plating. In contrast, adult AEC migrated and expressed MMP-2 and MMP-9 proteins only after 48 h of culture. AEC from hyperoxic rats were significantly more migratory through gelatin than control adult AEC, with significantly higher MMP-9 activity. Inhibition of MMPs with doxycycline reduced the migration of AEC from hyperoxic rats to the level of control adult AEC. Fibronectin-cultured “hyperoxic” AEC acquired a temporary capacity for migration similar to the A549 lung cancer cell line, which is both highly migratory and invasive and is derived from the AEC type 2 lineage. These data suggest that MMP activity is associated with a migratory phenotype in fetal, hyperoxic, and transformed AEC in vitro, and we speculate that MMPs may play a key mechanistic role in AEC migration in vivo during lung development and repair.

scholarly journals Fas activation alters tight junction proteins in acute lung injury

Thorax ◽  
2018 ◽  
Vol 74 (1) ◽  
pp. 69-82 ◽  
Author(s):  
Raquel Herrero ◽  
Lucia Prados ◽  
Antonio Ferruelo ◽  
Ferranda Puig ◽  
Rachele Pandolfi ◽  
...  
Keyword(s):  
Tight Junction ◽  
Fas Ligand ◽  
Alveolar Epithelial Cell ◽  
Intratracheal Instillation ◽  
Alveolar Epithelial Cells ◽  
Cell Monolayers ◽  
Alveolar Epithelial ◽  
Protein Permeability

Background:The acute respiratory distress syndrome (ARDS) is characterized by protein-rich oedema in the alveolar spaces, a feature in which Fas-mediated apoptosis of the alveolar epithelium has been involved.Objective:To determine whether Fas activation increases protein permeability by mechanisms involving disruption of the paracellular tight junction (TJ) proteins in the pulmonary alveoli.Methods: Protein permeability and the expression of TJ proteins were assessed in vivo in wild-type and Fas-deficient lpr mice 16 hours after the intratracheal instillation of recombinant human soluble Fas ligand (rh-sFasL), and at different time points in vitro in human pulmonary alveolar epithelial cells (HPAEpiC) exposed to rh-sFasLResults:Activation of the Fas pathway increased protein permeability in mouse lungs and altered the expression of the TJ proteins occludin and zonula occludens-1 in the alveolar–capillary membrane in vivo and in human alveolar epithelial cell monolayers in vitro. Blockade of caspase-3, but not inhibition of tyrosine kinase dependent pathways, prevented the alterations in TJ protein expression and permeability induced by the Fas/FasL system in human alveolar cell monolayers in vitro. We also observed that both the Fas-induced increase of protein permeability and disruption of TJ proteins occurred before cell death could be detected in the cell monolayers in vitro.Conclusion:Targeting caspase pathways could prevent the disruption of TJs and reduce the formation of lung oedema in the early stages of ARDS.

VEGF/Src signaling mediated pleural barrier damage and increased permeability contributes to sub-pleural pulmonary fibrosis

2021 ◽  
Author(s):  
Yu-Zhi Lu ◽  
Li-Mei Liang ◽  
Pei-Pei Cheng ◽  
Li Xiong ◽  
Meng Wang ◽  
...  
Keyword(s):  
Pulmonary Fibrosis ◽  
Alveolar Epithelial Cell ◽  
Mesothelial Cell ◽  
Fluorescein Isothiocyanate ◽  
Alveolar Epithelial Cells ◽  
Alveolar Epithelial ◽  
Src Signaling ◽  
Vitro Model

The distribution of fibrosis in idiopathic pulmonary fibrosis (IPF) is sub-pleural with basal predominance. Alveolar epithelial cell was considered as the key cell in the initial phase of IPF. However, the idea of activation and damage of alveolar epithelial cells is very difficult to explain why fibrosis distributes in the sub-pleural area. In this study, human pleural mesothelial cell (PMC) line and primary rat PMC was used as in vitro model. Intra-peritoneal injection of bleomycin was used for making a pulmonary fibrosis model. The integrity of cultured monolayer PMCs was determined by transepithelial electric resistance (TEER). Pleural permeability was estimated by measuring paracellular transport of fluorescein isothiocyanate (FITC)-conjugated dextran. Changes in lung tissue of IPF patients were analyzed by Masson's and immunofluorescence staining. We found bleomycin induced PMCs damage and increased PMCs permeability, increased PMCs permeability aggravated bleomycin-induced sub-pleural inflammation and pulmonary fibrosis. Moreover, bleomycin was found to activate VEGF/Src signaling which increased PMCs permeability. In vivo, inhibition of VEGF/Src signaling prevented bleomycin-induced sub-pleural pulmonary fibrosis. At last, activation of VEGF/Src signaling was confirmed in sub-pleural area in IPF patients. Taken together, our findings indicate that VEGF/Src signaling mediated pleural barrier damage and increased permeability which contributes to sub-pleural pulmonary fibrosis.

scholarly journals C3 Promotes Clearance of Klebsiella pneumoniae by A549 Epithelial Cells

2004 ◽  
Vol 72 (3) ◽  
pp. 1767-1774 ◽  
Author(s):  
Beatriz de Astorza ◽  
Guadalupe Cortés ◽  
Catalina Crespí ◽  
Carles Saus ◽  
José María Rojo ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Klebsiella Pneumoniae ◽  
Alveolar Epithelial Cells ◽  
Clinical Isolates ◽  
Complement Components ◽  
Innate Defense ◽  
Alveolar Epithelial

ABSTRACT The airway epithelium represents a primary site for contact between microbes and their hosts. To assess the role of complement in this event, we studied the interaction between the A549 cell line derived from human alveolar epithelial cells and a major nosocomial pathogen, Klebsiella pneumoniae, in the presence of serum. In vitro, we found that C3 opsonization of poorly encapsulated K. pneumoniae clinical isolates and an unencapsulated mutant enhanced dramatically bacterial internalization by A549 epithelial cells compared to highly encapsulated clinical isolates. Local complement components (either present in the human bronchoalveolar lavage or produced by A549 epithelial cells) were sufficient to opsonize K. pneumoniae. CD46 could competitively inhibit the internalization of K. pneumoniae by the epithelial cells, suggesting that CD46 is a receptor for the binding of complement-opsonized K. pneumoniae to these cells. We observed that poorly encapsulated strains appeared into the alveolar epithelial cells in vivo but that (by contrast) they were completely avirulent in a mouse model of pneumonia compared to the highly encapsulated strains. Our results show that bacterial opsonization by complement enhances the internalization of the avirulent microorganisms by nonphagocytic cells such as A549 epithelial cells and allows an efficient innate defense.

Gene transfer of hepatocyte growth factor by electroporation reduces bleomycin-induced lung fibrosis

2007 ◽  
Vol 292 (2) ◽  
pp. L529-L536 ◽  
Author(s):  
Amiq Gazdhar ◽  
Patrick Fachinger ◽  
Coretta van Leer ◽  
Jaroslaw Pierog ◽  
Mathias Gugger ◽  
...  
Keyword(s):  
Growth Factor ◽  
Gene Transfer ◽  
Pulmonary Fibrosis ◽  
Wound Repair ◽  
Alveolar Epithelial Cells ◽  
Epithelial Repair ◽  
Alveolar Epithelial ◽  
Hepatocyte Growth

Abnormal alveolar wound repair contributes to the development of pulmonary fibrosis after lung injury. Hepatocyte growth factor (HGF) is a potent mitogenic factor for alveolar epithelial cells and may therefore improve alveolar epithelial repair in vitro and in vivo. We hypothesized that HGF could increase alveolar epithelial repair in vitro and improve pulmonary fibrosis in vivo. Alveolar wound repair in vitro was determined using an epithelial wound repair model with HGF-transfected A549 alveolar epithelial cells. Electroporation-mediated, nonviral gene transfer of HGF in vivo was performed 7 days after bleomycin-induced lung injury in the rat. Alveolar epithelial repair in vitro was increased after transfection of wounded epithelial monolayers with a plasmid encoding human HGF, pCikhHGF [human HGF (hHGF) gene expressed from the cytomegalovirus (CMV) immediate-early promoter and enhancer] compared with medium control. Electroporation-mediated in vivo HGF gene transfer using pCikhHGF 7 days after intratracheal bleomycin reduced pulmonary fibrosis as assessed by histology and hydroxyproline determination 14 days after bleomycin compared with controls treated with the same vector not containing the HGF sequence (pCik). Lung epithelial cell proliferation was increased and apoptosis reduced in hHGF-treated lungs compared with controls, suggesting increased alveolar epithelial repair in vivo. In addition, profibrotic transforming growth factor-β1 (TGF-β1) was decreased in hHGF-treated lungs, indicating an involvement of TGF-β1 in hHGF-induced reduction of lung fibrosis. In conclusion, electroporation-mediated gene transfer of hHGF decreases bleomycin-induced pulmonary fibrosis, possibly by increasing alveolar epithelial cell proliferation and reducing apoptosis, resulting in improved alveolar wound repair.

scholarly journals Podoplanin interaction with caveolin-1 promotes tumour cell migration and invasion

2018 ◽  
Author(s):  
Luisa Pedro ◽  
Jacqueline D. Shields
Keyword(s):  
Tumour Cell ◽  
Surface Expression ◽  
Alveolar Epithelial Cells ◽  
Migration And Invasion ◽  
Dependent Manner ◽  
Caveolin 1 ◽  
Alveolar Epithelial ◽  
Podoplanin Expression

AbstractPodoplanin, a highly O-glycosylated type-1 transmembrane glycoprotein, found in lymphatic endothelial cells, podocytes, alveolar epithelial cells and lymph node fibroblasts is also expressed by tumour cells, and is correlated with more aggressive disease. Despite numerous studies documenting podoplanin expression, the mechanisms underlying its tumour-promoting functions remain unclear. Using a murine melanoma cell line that endogenously expresses podoplanin, we demonstrate interactions with proteins necessary for cytoskeleton reorganization, adhesion and matrix degradation, and endocytosis/receptor recycling but also identify a novel interaction with caveolin-1. We generated a panel of podoplanin and caveolin-1 variants to determine the molecular interactions and functional consequences of these interactions. Complementary in vitro and in vivo systems confirmed the existence of a functional cooperation in which surface expression of both full length, signalling competent podoplanin and caveolin-1 are necessary to induce directional migration and invasion, which is executed via PAK1 and ERK1 pathways. Our findings establish that podoplanin signalling mediates the invasive properties of melanoma cells in a caveolin-1 dependent manner.Summary StatementThis manuscript describes a new interaction and functional cooperation between podoplanin and caveolin1 that drives tumour cell invasion into surrounding tissues.

Sign in / Sign up

Export Citation Format

Share Document