Eun-Ju Lee

Soonchunhyang University, Onyang, Chungcheongnam-do, South Korea

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Publications (4)11.99 Total impact

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    ABSTRACT: Background: Exacerbation of COPD is a major risk factor for bad prognosis of COPD. A few plasma proteins have been discovered to associate with hospital admission due to exacerbation up to date. We tried to find new plasma biomarkers to predict the exacerbation of COPD. Methods: We examined the plasma of normal control (n = 8) and COPD stable (n = 8) and exacerbation (n = 8) using 2-Dimentional Electrophoresis. The differentially expressed protein spots were identified by MALDI-TOF. ELISA were performed for quantitative measurement of RARα in plasma from normal control (n = 37) and COPD (n = 35). Results: 17 proteins were differentially expressed in plasma between stable and exacerbation state in the subjects with COPD. Identification using MALDI-TOF showed that retinoic acid receptor alpha, ninein, isoform CRA_a, alpha-1 antitrypsin, fibrinogen gamma, tyrosyl-DNA phosphodiesterase 2, and T cell receptor delta chain were increased in exacerbation of COPD, while fibrin beta, Crystal Structure Of An Autoimmune Complex Between A Human Igm RF* And Igg1 Fc, transferrin, serpin peptidase inhibitor member 6, complement factor B preproprotein, Chain B, Crig Bound To C3c, and WD repeat-containing protein 1 isoform 1 were decreased. Quantitative measurement showed that RARα plasma levels significantly increased in exacerbation state compared to stable state of COPD (n = 14). In the plasma of stable state, the COPD subjects (n = 14) having more than 0.4 time/yr of admission had very high levels of RAR alpha protein and those (n = 11) having less than 0.4 times/yr of admission had the intermediate levels compared to those having no exacerbation (n = 10). ROC analysis of RAR alpha levels to frequency of admission showed an area under the curve of 0.844. A cut-off of 0.154 ng/ml of RAR alpha predicted hospital admission with a sensitivity of 71.4% and a specificity of 92.8%. Conclusion: The proteomic analysis of plasma indicates that alteration of several proteins may be associated with admission of COPD. Among them, plasma RAR alpha level may predict hospital admission with a sensitivity of 71.4% and a specificity of 92.8%.
    No preview · Article · Oct 2013 · COPD Journal of Chronic Obstructive Pulmonary Disease
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    ABSTRACT: The inhalation of silica particles induces silicosis, an inflammatory and fibrotic lung disease characterized by the early accumulation of macrophages and neutrophils in the airspace and subsequent appearance of silicotic nodules as a result of progressive fibrosis. This study evaluated whether apolipoprotein A1 (ApoA1) protects against ongoing fibrosis and promotes the resolution of established experimental lung silicosis. Crystallized silica was intratracheally administered to 6- to 8-week-old transgenic mice expressing human ApoA1 in their alveolar epithelial cells (day 0). ApoA1 was overexpressed beginning on day 7 (ApoA1_D7 group) or day 15 (ApoA1_D15 group). The mice were sacrificed on day 30 for an evaluation of lung histology; the measurement of collagen, transforming growth factor-b1 and lipoxin A4; and a TUNEL assay for apoptotic cells. The ApoA1_D7 and D15 groups showed significant reductions in the silica-induced increase in inflammatory cells, silicotic nodule area, and collagen deposition compared with the silica-treated ApoA1 non-overexpressing mice. The level of transforming growth factor-b1 decreased in the bronchoalveolar lavage fluid, whereas lipoxin A4 was increased in the ApoA1_D7 and D15 groups compared with the silica-treated ApoA1 non-overexpressing mice. The silica-induced increase in the number of apoptotic cells was significantly reduced in the lungs of mice overexpressing ApoA1. Overexpression of ApoA1 decreased silica-induced lung inflammation and fibrotic nodule formation. The restoration of lipoxin A4 may contribute to the protective effect of ApoA1 overexpression against silica-induced lung fibrosis.
    Preview · Article · Feb 2013 · PLoS ONE
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    ABSTRACT: Aspirin-exacerbated respiratory diseases (AERD) are associated with the metabolism of arachidonic acid. FPR2 (formyl peptide receptor2) is a high-affinity ligand receptor for potent anti-inflammatory lipid metabolites: lipoxins. Thus, functional alterations of the FPR2 may contribute to AERD. We investigated the relationship between single-nucleotide polymorphisms (SNPs) in the FPR2 and AERD. Asthmatics were categorized into AERD <15% decreases in forced expiratory volume in one second (FEV(1)), and/or naso-ocular reactions after oral aspirin challenge (n=170) and aspirin-tolerant asthma (ATA, n=268). In all, 11 SNPs were genotyped. FPR2 protein expressions on CD14-positive monocytes in peripheral blood were measured using flow cytometric analysis. We performed RT-PCR of the FPR2 mRNA expressed by peripheral blood mononuclear cells. Logistic regression analysis showed that the minor allele frequency of FPR2 -4209T>G (rs1769490) in intron 2 was significantly lower in the AERD group (n=170) than in the ATA group (n=268) (P=0.006, P(corr)=0.04, recessive model). The decline of FEV(1) after aspirin challenge was significantly lower in the subjects with GG homozygotes of FPR2 -4209T>G than those with the other genotypes (P=0.0002). Asthmatic homozygotes for FPR2 -4209T>G minor allele exhibited significantly higher FPR2 protein expression in CD14-positive monocytes than did those with the common allele of FPR2 -4209T>G allele (P=0.01). There was no difference in the expression of the wild form and the exon 2 deleted variant form of FPR2 gene according to the genotypes of FPR2 -4209T>G. The minor allele at FPR2 -4209T>G may have a protective role against the development of AERD, via increase of FPR2 protein expression in inflammatory cells.
    Preview · Article · Mar 2012 · Journal of Human Genetics
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    ABSTRACT: Environmental pollutant exposure is associated with adverse respiratory outcomes. The phosphorylation of enzymes activates or deactivates many cellular processes and is related to the development of lung diseases such as asthma and chronic obstructive pulmonary disease. However, little is known about protein phosphorylation of bronchial epithelial cells in response to airborne particulates. Herein, we screened differentially phosphorylated proteins in TiO₂-treated epithelial cells and validated the change in GSTP1 protein phosphorylation. Two-dimensional electrophoresis was adopted for differential display proteomics of TiO₂-treated BEAS-2B cell lysates. Phosphoproteins were screened using Pro-Q® Diamond phosphoprotein gel stain and identified by MALDI-TOF/TOF analysis. Immunoprecipitation and immunoblotting were performed for quantitative measurement of GSTP1 phosphorylation in cell lysates. Normalized relative intensities of nine phosphorylated proteins increased after TiO₂ treatment, whereas those of 12 proteins decreased in the BEAS-2B cell lysates. From gene ontology and pathway analysis, proteins involved in signal transduction were commonly identified, followed by cytoskeletal proteins, proteins from oxidation and antioxidation pathways, proteins catalyzing reductions, and those involved in cellular process, transport, and modification. Immunoblotting with anti-GSTP1 antibody demonstrated no change in GSTP1 protein levels in the lysates of BEAS-2B cells after treatment with TiO₂ particles; blotting with anti-phosphoserine and anti-phosphotyrosine antibodies showed dose-dependent decreases in phosphoserine and phosphotyrosine proteins. Stimulation with particulates phosphorylated and dephosphorylated several proteins in epithelial cells, and serine and tyrosine protein phosphorylation of GSTP1 decreased. These data indicate that airborne particles affect the pattern of phosphorylation of proteins involved in defense or apoptosis of respiratory epithelium.
    Preview · Article · Mar 2011 · Toxicology