Inhibition of β-Defensin Gene Expression in Airway Epithelial Cells by Low Doses of Residual Oil Fly Ash is Mediated by Vanadium

Residual oil fly ash (ROFA) is an industrial pollutant that contains metals, acids, and unknown materials complexed to a particulate core. The heterogeneous composition of ROFA hampers finding the mechanism(s) by which it and other particulate pollutants cause airway toxicity. To distinguish culpable factors contributing to the effects of ROFA, synthetic polymer microsphere (SPM) analogs were synthesized that resembled ROFA in particle size (2 and 6 μm in diameter) and zeta potential (−29 mV). BEAS-2B human bronchial epithelial cells and dorsal root ganglion neurons responded to both ROFA and charged SPMs with an increase in intracellular Ca2+concentration ([Ca2+]i) and the release of the proinflammatory cytokine interleukin-6, whereas neutral SPMs bound with polyethylene glycol (0-mV zeta potential) were relatively ineffective. In dorsal root ganglion neurons, the SPM-induced increases in [Ca2+]iwere correlated with the presence of acid- and/or capsaicin-sensitive pathways. We hypothesized that the acidic microenvironment associated with negatively charged colloids like ROFA and SPMs activate irritant receptors in airway target cells. This causes subsequent cytokine release, which mediates the pathophysiology of neurogenic airway inflammation.

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Respiratory epithelial cells demonstrate lactoferrin receptors that increase after metal exposure

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.1999.276.6.l933 ◽

1999 ◽

Vol 276 (6) ◽

pp. L933-L940 ◽

Cited By ~ 9

Author(s):

Andrew J. Ghio ◽

Jacqueline D. Carter ◽

Lisa A. Dailey ◽

Robert B. Devlin ◽

James M. Samet

Keyword(s):

Oxidative Stress ◽

Fly Ash ◽

Epithelial Cells ◽

Airway Epithelial Cells ◽

Metal Exposure ◽

Airway Epithelial ◽

Respiratory Epithelial Cells ◽

Catalytically Active ◽

Oil Fly Ash ◽

Respiratory Epithelial

Human airway epithelial cells can increase expression of both lactoferrin and ferritin after exposure to catalytically active metal. These proteins transport and store metal, with coordination sites fully complexed, and therefore can diminish the oxidative stress. The intracellular transport of lactoferrin results in a transfer of complexed metal to ferritin, where it is stored in a less reactive form. This effort to control the injurious properties of metals would be facilitated by lactoferrin receptors (LfRs) on airway epithelial cells. We tested the hypotheses that 1) LfRs exist on respiratory epithelial cells and 2) exposure to both an air pollution particle, which has abundant concentrations of metals, and individual metal salts increase the expression of LfRs. Before exposure to either the particle or metals, incubation of BEAS-2B cells with varying concentrations of125I-labeled lactoferrin demonstrated lactoferrin binding that was saturable. Measurement of125I-lactoferrin binding after the inclusion of 100 μg/ml of oil fly ash in the incubation medium demonstrated increased binding within 5 min of exposure, which reached a maximal value at 45 min. Inclusion of 1.0 mM deferoxamine in the incubation of BEAS-2B cells with 100 μg/ml of oil fly ash decreased lactoferrin binding. Comparable to the particle, exposure of BEAS-2B cells to either 1.0 mM vanadyl sulfate or 1.0 mM iron (III) sulfate, but not to nickel sulfate, for 45 min elevated LfR activity. We conclude that LfRs on respiratory epithelial cells increased after exposure to metal. LfRs could participate in decreasing the oxidative stress presented to the lower respiratory tract by complexing catalytically active metals.

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Gene Expression Profiles of Human Small Airway Epithelial Cells Treated with Low Doses of 14- and 16-Membered Macrolides

Biochemical and Biophysical Research Communications ◽

10.1006/bbrc.2001.5550 ◽

2001 ◽

Vol 287 (1) ◽

pp. 198-203 ◽

Cited By ~ 16

Author(s):

Yasunari Yamanaka ◽

Mayumi Tamari ◽

Tatsutoshi Nakahata ◽

Yusuke Nakamura

Keyword(s):

Gene Expression ◽

Epithelial Cells ◽

Expression Profiles ◽

Gene Expression Profiles ◽

Airway Epithelial Cells ◽

Small Airway ◽

Low Doses ◽

Airway Epithelial ◽

Small Airway Epithelial Cells

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Somatic cell hemoglobin modulates nitrogen oxide metabolism in the human airway epithelium

Scientific Reports ◽

10.1038/s41598-021-94782-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Nadzeya Marozkina ◽

Laura Smith ◽

Yi Zhao ◽

Joe Zein ◽

James F. Chmiel ◽

...

Keyword(s):

Gene Expression ◽

Epithelial Cells ◽

Nitrogen Oxides ◽

Airway Epithelium ◽

Airflow Obstruction ◽

Airway Epithelial Cells ◽

Airway Epithelial ◽

Human Airway ◽

Human Airway Epithelium ◽

Human Airway Epithelial Cells

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.

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Role of soluble metals in oil fly ash-induced airway epithelial injury and cytokine gene expression

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.1999.277.3.l498 ◽

1999 ◽

Vol 277 (3) ◽

pp. L498-L510 ◽

Cited By ~ 26

Author(s):

Janice A. Dye ◽

Kenneth B. Adler ◽

Judy H. Richards ◽

Kevin L. Dreher

Keyword(s):

Gene Expression ◽

Fly Ash ◽

Dependent Manner ◽

Airway Epithelial ◽

Tracheal Epithelial Cells ◽

Inflammatory Protein ◽

Tracheal Epithelial ◽

Oil Fly Ash ◽

Dose Dependent ◽

Macrophage Inflammatory Protein

Particulate matter (PM) metal content and bioavailability have been hypothesized to play a role in the health effects epidemiologically associated with PM exposure, in particular that associated with emission source PM. Using rat tracheal epithelial cells in primary culture, the present study compared and contrasted the acute airway epithelial effects of an emission source particle, residual oil fly ash (ROFA), with that of its principal constitutive transition metals, namely iron, nickel, and vanadium. Over a 24-h period, exposure to ROFA, vanadium, or nickel plus vanadium, but not to iron or nickel, resulted in increased epithelial permeability, decreased cellular glutathione, cell detachment, and lytic cell injury. Treatment of vanadium-exposed cells with buthionine sulfoximine further increased cytotoxicity. Conversely, treatment with the radical scavenger dimethylthiourea inhibited the effects in a dose-dependent manner. RT-PCR analysis of RNA isolated from ROFA-exposed rat tracheal epithelial cells demonstrated significant macrophage inflammatory protein-2 and interleukin-6 gene expression as early as 6 h after exposure, whereas gene expression of inducible nitric oxide synthase was maximally increased 24 h postexposure. Again, vanadium (not nickel) appeared to be mediating the effects of ROFA on gene expression. Treatment with dimethylthiourea inhibited both ROFA- and vanadium-induced gene expression in a dose-dependent manner. Corresponding effects were observed in interleukin-6 and macrophage inflammatory protein-2 synthesis. In summary, generation of an oxidative stress was critical to induction of the ROFA- or vanadium-induced effects on airway epithelial gene expression, cytokine production, and cytotoxicity.

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Exploring host-pathogen interactions at the epithelial surface: application of transcriptomics in lung biology

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00242.2006 ◽

2007 ◽

Vol 292 (2) ◽

pp. L367-L377 ◽

Cited By ~ 6

Author(s):

Joost B. Vos ◽

Nicole A. Datson ◽

Klaus F. Rabe ◽

Pieter S. Hiemstra

Keyword(s):

Gene Expression ◽

Epithelial Cells ◽

Large Scale ◽

Brain Research ◽

Airway Epithelial Cells ◽

Airway Epithelial ◽

Host Pathogen Interactions ◽

Epithelial Surface ◽

Complex Interactions ◽

Host Pathogen

The epithelial surface of the airways is the largest barrier-forming interface between the human body and the outside world. It is now well recognized that, at this strategic position, airway epithelial cells play an eminent role in host defense by recognizing and responding to microbial exposure. Conversely, inhaled microorganisms also respond to contact with epithelial cells. Our understanding of this cross talk is limited, requiring sophisticated experimental approaches to analyze these complex interactions. High-throughput technologies, such as DNA microarray analysis and serial analysis of gene expression (SAGE), have been developed to screen for gene expression levels at large scale within single experiments. Since their introduction, these hypothesis-generating technologies have been widely used in diverse areas such as oncology and brain research. Successful application of these genomics-based technologies has also revealed novel insights in host-pathogen interactions in both the host and pathogen. This review aims to provide an overview of the SAGE and microarray technology illustrated by their application in the analysis of host-pathogen interactions. In particular, the interactions between epithelial cells in the human lungs and clinically relevant microorganisms are the central focus of this review.

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Recent Advances in Molecular Biology of Human Bocavirus 1 and Its Applications

Frontiers in Microbiology ◽

10.3389/fmicb.2021.696604 ◽

2021 ◽

Vol 12 ◽

Author(s):

Liting Shao ◽

Weiran Shen ◽

Shengqi Wang ◽

Jianming Qiu

Keyword(s):

Gene Expression ◽

Dna Repair ◽

Epithelial Cells ◽

Airway Epithelial Cells ◽

Structural Proteins ◽

Human Bocavirus ◽

Airway Epithelial ◽

Raav Vector ◽

Human Airway ◽

Non Coding Rna

Human bocavirus 1 (HBoV1) was discovered in human nasopharyngeal specimens in 2005. It is an autonomous human parvovirus and causes acute respiratory tract infections in young children. HBoV1 infects well differentiated or polarized human airway epithelial cells in vitro. Unique among all parvoviruses, HBoV1 expresses 6 non-structural proteins, NS1, NS1-70, NS2, NS3, NS4, and NP1, and a viral non-coding RNA (BocaSR), and three structural proteins VP1, VP2, and VP3. The BocaSR is the first identified RNA polymerase III (Pol III) transcribed viral non-coding RNA in small DNA viruses. It plays an important role in regulation of viral gene expression and a direct role in viral DNA replication in the nucleus. HBoV1 genome replication in the polarized/non-dividing airway epithelial cells depends on the DNA damage and DNA repair pathways and involves error-free Y-family DNA repair DNA polymerase (Pol) η and Pol κ. Importantly, HBoV1 is a helper virus for the replication of dependoparvovirus, adeno-associated virus (AAV), in polarized human airway epithelial cells, and HBoV1 gene products support wild-type AAV replication and recombinant AAV (rAAV) production in human embryonic kidney (HEK) 293 cells. More importantly, the HBoV1 capsid is able to pseudopackage an rAAV2 or rHBoV1 genome, producing the rAAV2/HBoV1 or rHBoV1 vector. The HBoV1 capsid based rAAV vector has a high tropism for human airway epithelia. A deeper understanding in HBoV1 replication and gene expression will help find a better way to produce the rAAV vector and to increase the efficacy of gene delivery using the rAAV2/HBoV1 or rHBoV1 vector, in particular, to human airways. This review summarizes the recent advances in gene expression and replication of HBoV1, as well as the use of HBoV1 as a parvoviral vector for gene delivery.

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