• Title/Summary/Keyword: neutrophils

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Endotoxin-induced Acute Lung Injury is Mediated by PAF Produced via Remodelling of Lyso PAF in the Lungs

  • Lee, Young-Man;Kim, Teo-An
    • The Korean Journal of Physiology and Pharmacology
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    • v.4 no.3
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    • pp.219-226
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    • 2000
  • In order to elucidate the role of platelet activating factor (PAF) in the acute lung injury induced by endotoxin (ETX), activities of phospholipase A2, lyso PAF acetyltransferase and oxidative stress by neutrophilic respiratory burst were probed in the present study. To induce acute lung injury, $100\;{\mu}g$ of E.coli ETX (type 0127; B8) was instilled directly into the tracheae of Sprague-Dawley rats. Five hours after the ETX instillation, induction of acute lung injury was confirmed by lung leak index and protein contents in the bronchoalveolar lavage (BAL) fluid. At the same time, lung phospholipase A2 (PLA2) activity and expression of group I and II secretory type PLA2 were examined. In these acutely injured rats, ketotifen fumarate, known as lyso PAF acetyltransferase inhibitor and mepacrine were administered to examine the role of PAF in the pathogenesis of the acute lung injury. To know the effect of the ETX in the synthesis of the PAF in the lungs, lyso PAF acetyltransferase activity and PAF content in the lungs were measured after treatments of ETX, ketotifen fumarate and mepacrine. In addition, the role of neutrophils causing the oxidative stress after ETX was examined by measuring lung myeloperoxidase (MPO) and enumerating neutrophils in the BAL fluid. To confirm the oxidative stress in the lungs, pulmonary contents of malondialdehyde (MDA) were measured. After instillation of the ETX in the lungs, lung leak index increased dramatically (p<0.001), whereas mepacrine and ketotifen decreased the lung leak index significantly (p<0.001). Lung PLA2 activity also increased (p<0.001) after ETX treatment compared with control, which was reversed by mepacrine and ketotifen (p<0.001). In the examination of expression of group I and II secretory PLA2, mRNA synthesis of the group II PLA2 was enhanced by ETX treatment, whereas ketotifen and WEB 2086, the PAF receptor antagonist, decreased the expression. The activity of the lysoPAF acetyltransferase increased (p<0.001) after treatment of ETX, which implies the increased synthesis of PAF by the remodelling of lysoPAF in the lungs. Consequently, the contents of the PAF in the lungs were increased by ETX compared with control (p<0.001), while mepacrine (p<0.001) and ketotifen (p<0.01) decreased the synthesis of the PAF in the lungs of ETX treated rats. The infiltration of the neutrophils was confirmed by measuring and enumerating lung MPO and the neutrophils in the BAL fluid respectively. Compared with control, ETX increased lung MPO and number of neutrophils in BAL significantly (p<0.001) whereas mepacrine and ketotifen decrerased number of neutrophils (p<0.001) and MPO (p<0.05, p<0.001, respectively). The lung MDA contents were also increased (p<0.001) by ETX treatment, but treatment with mepacrine (p<0.001) and ketotifen (p<0.01) decreased the lung MDA contents. Collectively, we conclude that ETX increases PLA2 activity, and that the subsequently increased production of PAF was ensued by the remodelling of the lyso PAF resulting in tissue injury by means of oxidative stress in the lungs.

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Bovine leukocyte adhesion deficiency

  • Kehrli, Marcus E. Jr.;Park, Yong-ho;Yoo, Han-sang
    • Korean Journal of Veterinary Research
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    • v.39 no.2
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    • pp.247-256
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    • 1999
  • A disease of young Holstein calves characterized by recurrent pneumonia, ulcerative and granulomatous stomatitis, enteritis with bacterial overgrowth, periodontitis, delayed wound healing, persistent neutrophilia and death at an early age had been originally described in 1983 and again in 1987. Most of these calves had stunted growth and a persistent, progressive neutrophilia (often exceeding 100,000/ml). By investigation of pedigrees, all of the affected calves have now been traced to a common sire and confirmed by polymerase chain reaction (PCR) diagnostic DNA testing to be homozygous carriers of a defective allele for bovine CD18. Neutrophils from these calves have several functional deficits and, most importantly, fail to adhere in a ${\beta}_2$-integrin dependent manner. The ${\beta}_2$-integrins represent a family of glycoproteins which participate in various leukocyte adhesion reactions during host defense. The presence or absence of ${\beta}_2$-integrin molecules can be demonstrated on the surface of neutrophils, monocytes and lymphocytes from normal or affected calves using specific monoclonal antibodies and flow cytometry, or by colloidal gold immunolabeling and scanning electron microscopy in backscatter mode. Deficiency of the ${\beta}_2$-integrins on all leukocyte types in Holstein calves is analogous to leukocyte adhesion deficiency (LAD) seen in humans. Neutrophils in bovine (BLAD) and human LAD patients are unable to adhere to the endothelial lining of the cardiovascular system thus interrupting egression of neutrophils into infected tissues. Other leukocytes, while still deficient in expression of the ${\beta}_2$-integrins, are still able to efficiently egress from the blood stream due to interactions of other adhesion molecules that are not as highly expressed on neutrophils. Both BLAD cattle and LAD children (who do not receive bone marrow transplants) often die at an early age as a result of the failure of neutrophils to extravasate into infected tissues. In 1991, Shuster, et $al^{27}$, identified two point mutations within the alleles encoding bovine CD18 in a Holstein calf afflicted with leukocyte adhesion deficiency. One mutation causes an aspartic acid to glycine substitution at amino acid 128 (D128G) in an extracellular region of this adhesion glycoprotein that is highly conserved (> 95% identity) between humans, cattle and mice. The other mutation is silent. Numerous calves with clinical symptoms of leukocyte adhesion deficiency have since been tested and all have been found homozygous for the D128G allele. In addition, calves homozygous far the D128G allele have been identified during widespread DNA testing in the United States. All cattle with the mutant allele are related to one bull, who through artificial insemination (A.I.), sired many calves in the 1950's and 1960's. The carrier frequency of the D128G CD18 allele among U.S. Holstein cattle had reached approximately 15% among active A.I. bulls and 8% among cows. By 1993, the organization of the dairy industry and the diagnostic test developed to genotype cattle, enabled virtually complete eradication of bovine leukocyte adhesion deficiency among current and future A.I. bulls.

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Effect of CD14, Toll-like receptors, cytoskeletal inhibitors and $NF-{\kappa}B$ inhibitor on MMP-8 release from human neutrophils induced by E. coli lipopolysaccharides. (E. coli lipopolysaccharides로 유도된 사람 호중구에서 CD14, Toll-like receptors, cytoskeletal inhibitors 그리고 $NF-{\kappa}B$ inhibitor가 MMP-8 분비에 미치는 영향)

  • Yang, Seung-Min;Kim, Tae-Il;Seol, Yang-Jo;Lee, Yong-Moo;Ku, Young;Chung, Chong-Pyoung;Han, Soo-Boo;Rhyu, In-Chul
    • Journal of Periodontal and Implant Science
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    • v.35 no.2
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    • pp.427-436
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    • 2005
  • Objective: MMP-8 is a neutrophil enzyme and its level increases in some inflammatory diseases, including periodontal disease. We knew that the lipopolysaccharide of E.coli(E-LPS) induced MMP-8 release from human neutrophils. E-LPS is known to induce the production and release of inflammatory cytokines through CD14, Toll-like receptor(TLR). In the present study, we investigated whether MMP-8 release by E-LPS is induced via CD14-TLR pathway and the cellular mechanism of MMP-8 release in human neutrophils. Material and methods: Human neutrophils were isolated from the peripheral blood of healthy donors and pre-incubated in medium containing antibodies against CD14, anti-TLR2 and anti-TLR4 or several inhibitors of microtubules and microfilaments and then incubated with E-LPS. The cells were treated TPCK and E-LPS simultaneously. The MMP-8amount in the culture medium was determined using ELISA. Results: E-LPS increased MMP-8release from neutrophils and its induction was inhibited by anti-CD14 and anti-TLR4 but not by anti-TLR2 antibodies. The inhibitors of microtubule and microfilament polymerization significantly decreased E-LPS-induced MMP-8release. TPCK inhibited E-LPS-induced MMP-8 release. Conclusion: These results suggest that MMP-8 release is induced by E-LPS via the CD14-TLR4 signal pathway in human neutrophils and may be depedent on microtubule and microfilament systems and $NF-{\kappa}B$ pathway.

Induction of Spontaneous Neutrophil Apoptosis by 4-O-Methyl-Ascochlorin, A Prenyl Phenol Compound (프레닐 페놀계 항생제인 4-O-methyl-ascochlorin에 의한 호중구 세포사멸의 유도)

  • Son Dong-Aoon;Lee Sun-Young;Lee Min-Jung;Park Joo-In;Hong Young-Seob;Lee Yong-Hwan;Chang Young-Chae;Kwak Jong-Young
    • Journal of Life Science
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    • v.16 no.1
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    • pp.30-36
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    • 2006
  • Neutrophils are short-lived leukocytes that play a vital role in immune responses to bacteria, yeast, and fungi. This study was performed to investigate the effect of 4-O-methyl-ascochlorin (MAC), an anti-tumor, antibiotic, and anti-fungal prenyl-phenol compound on the spontaneous apoptosis of human neutrophils. MAC time- and dose-dependently accelerated the spontaneous apoptosis of human neutrophils. The effect of MAC on neutrophil apoptosis was blocked by pre-treatment of the neutrophils with specific inhibitors of pancaspase (zVAD-fmk), caspase-8 (zIETD-fmk), or caspase-3 (zDEVD-fmk). The cleavage of procaspase-8 and procaspase-3 was increased by MAC. Mitochondrial permeability, which was measured by the retention of $DiOC_6(3)$, was dose-de-pendently increased by MAC but the change of mitochondrial permeability was not blocked by pretreatment of neutrophils with zIETD-fmk. These results suggest that MAC induces neutrophil apoptosis by caspase-8-dependent but mitochondria-independent manner.

Transepithelial Migration of Neutrophils in Response to Leukotriene $B_4$ is Mediated by a Reactive Oxygen Species-ERK-linked Cascade

  • Woo, Chang-Hoon;Kim, Jae-Hong
    • Proceedings of the PSK Conference
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    • 2003.04a
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    • pp.103-106
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    • 2003
  • The epithelial cells that form a barrier lining the lung airway are key regulators of neutrophil trafficking into the airway lumen in a variety of lung inflammatory diseases. Although the lipid mediator leukotriene B$_4$ (LTB$_4$) is known to be a principal chemoattractant for recruiting neutrophils to inflamed sites across the airway epithelium, the precise signaling mechanism involved remains largely unknown. (omitted)

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Effects of Adenosine and $N^6-cyclopentyladenosine$ on Superoxide Production, Degranulation and Calcium Mobilization in Activated Neutrophils (Adenosine과 $N^6-cyclopentyladenosine$이 활성화된 중성호성 백혈구에서 Superoxide 생성, 탈과립과 칼슘동원에 나타내는 영향)

  • Kim, Woo-Jung;Shin, Yong-Kyoo;Han, Eun-Sook;Lee, Chung-Soo
    • The Korean Journal of Pharmacology
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    • v.31 no.3
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    • pp.333-344
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    • 1995
  • The effects of adenosine and $N^6-cyclopentyladenosine$ (CPA) on superoxide production, myeloperoxidase release and $Ca^{2+}$ mobilization stimulated by fMLP in neutrophils were investigated. The effects were also observed on the stimulatory actions of C5a and PMA and the responses in lipopolysaccharide-primed neutrophils. In addition, the involvement of cAMP in the inhibitory action of adenosine was examined. The fMLP-stimulated neutrophil respiratory burst, degranulation and intracellular $Ca^{2+}$ mobilization may be regulated by activation of adenosine receptors. Adenosine may not affect the stimulated neutrophil responses due to activation of protein kinase C. fMLP-stimulated respiratory burst in lipopolysaccharide-primed neutrophils may be less sensitive to adenosine, compared with nonprimed cells. The inhibitory effect of theophylline in the presence of adenosine on neutrophil responses appears to be ascribed to accumulation of intracellular cAMP.

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A Study on the Mechanism of Immunomodulating Effects of Moxifloxacin in Oleic Acid-Induced Acute Lung Injury

  • Lee, Young-Man
    • Tuberculosis and Respiratory Diseases
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    • v.71 no.2
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    • pp.97-105
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    • 2011
  • Background: It was hypothesized that the immunomodulating effects of moxifloxacin contribute to ameliorate oleic acid (OA)-induced acute lung injury (ALI) by suppression of cytosolic phospholipase A2 (cPLA2). This was based on observations from experiments on rats associated with neutrophilic respiratory burst, cPLA2 activity, and expressions of cPLA2, $TNF{\alpha}$, and COX-II in the lung. Methods: ALI was induced by intravenous injection of OA in male Sprague-Dawley rats. Five hours after OA injection, protein content in bronchoalveolar lavage (BAL), lung myeloperoxidase (MPO) activity, and numbers of BAL neutrophils were measured. As an index of oxidative stress-induced lung injury, the content of malondialdehyde (MDA) in lung tissues was also determined. Lung histology, immunohistochemistry and determination of activity of cPLA2 in lung tissues were carried out. In addition, Western blotting of $TNF{\alpha}$ and COX-II in lung tissues was performed. Results: The accumulation of neutrophils in the lungs was observed after OA injection. BAL protein was increased along with neutrophilic infiltration and migration by OA. Moxifloxacin decreased all of these parameters of ALI and ameliorated ALI histologically. The increased malondialdehyde (MDA) in the lung by OA was also decreased by moxifloxacin. Moxifloxacin not only suppressed cPLA2 expression in the lungs and neutrophils but also decreased cPLA2 activity in lung tissues of rats given OA. The enhanced expressions of $TNF{\alpha}$ and COX-2 in the lung tissues of rats given OA were also suppressed by moxifloxacin. Conclusion: Moxifloxacin inhibited cPLA2 and down-regulated $TNF{\alpha}$ and COX-2 in the lungs of rats given OA, which resulted in the attenuation of inflammatory lung injury.

Fine Needle Aspiration Cytologic Findings of Inflammatory Breast Diseases (유방 염증성 질환의 세침흡인소견)

  • Yoon, Hye-Kyoung;Park, Seol-Mi;Kang, Mi-Sun;Yang, Young-Il;Kim, Chan-Hwan
    • The Korean Journal of Cytopathology
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    • v.6 no.2
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    • pp.156-162
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    • 1995
  • Fine needle aspiration of the breast is an important diagnostic tool in malignant lesions, but is also useful in differentiation of inflammatory breast diseases mimicking carcinoma clinically and radiologically. Recently, the authors have experienced eight biopsy-proven cases of chronic inflammatory diseases of the breast, which consisted of 4 cases of duct ectasia, 2 cases of fat necrosis, and a case of tuberculous mastitis and granulomatous mastitis respectively. Their cytologic features mainly based on the components and the relative frequency of inflammatory cells were evaluated for differential diagnosis of chronic inflammatory breast diseases. The results are as follows; 1. In cases of duct ectasia, varying amount of neutrophils, mononuclear leukocytes, histiocytes and multinucleated giant cells were intermixed with benign epithelial cell clusters. 2 Abundant fat tissue fragments were diagnostic for fat necrosis. Histiocytes and mononuclear cells were main components but not rich, and neutrophils and giant cells were infrequently observed. 3. Characteristic granulomas composed of epithelioid cells, mononuclear leukocytes and Langhans' type giant cells and lymphocytic infiltrates were conspicuous in tuberculous mastitis, and occasionally neutrophils, necrotic materials and epithelial cell clusters were found 4. In granulomatous mastitis, epithelioid cell granulomas were also noted but numerous neutrophils and histiocytes were intermingled within or outside the granulomas.

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Germanium Increases Alveolar Macrophage Engulfment of Apoptotic Neutrophils in Acute Lung Injury Induced by Endotoxin (내독소로 유도된 급성 폐 손상에서 게르마늄의 투여로 인한 호중구 세포사의 증가)

  • Cho, Hyun-Gug
    • Applied Microscopy
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    • v.35 no.4
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    • pp.84-90
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    • 2005
  • Neutrophils that influx into the alveolar spaces from circulatory bloods play a important role in pathogenesis of acute lung injury. During the acute inflammatory phase, in order to investigate the acceleration of macrophage phagocytosis to the neutrophils is able to reduce the neutrophil-derived acute lung injury, endotoxemia was induced by insufflation of lipopolysaccharide intratracheally and organic germanium was injected intraperitoneally after endotoxin treatment. At 5 h after endotoxin treatment, lung weight and BAL protein concentration are significantly increased (p<0.001) compared to sham, and that was remarkedly decreased (p<0.001, p<0.01) by injection of germanium. In addition germanium treatment resulted to decreased the number of alveolar PMNs and to increase the percentage of engulfed neutrophils by alveolar macrophages. These observations indicate that organic germanium may have a role of reduction to neutrophil-derived acute lung injury in endotoxemia.

Role of Retinoic Acid in Spontaneous Apoptosis of Human Neutrophils

  • Yang, Eun-Ju;Lee, Ji-Sook;Kim, Dong-Hee;Min, Bok-Kee;Hyun, Sung-Hee;Kim, In-Sik
    • Biomedical Science Letters
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    • v.13 no.4
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    • pp.279-285
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    • 2007
  • Although retinoic acid has been known as either anti-inflammatory or pro-inflammatory molecule, depending on the cell type, its exact role in mature human neutrophils has not been fully explored. In this study, we investigate the effects of retinoic acid on neutrophil apoptosis and the associated mechanism and found that 9-cis retinoic acid (9CRA) significantly inhibits the spontaneous apoptosis of neutrophils. Its effect is increased by co-treatment with $TNF-\alpha$ (P<0.05). The 9CRA-induced inhibition is blocked by the following enzyme inhibitors: Ly 294002, phosphoinoside (PI)-3 kinase inhibitor, U73122, a phospholipase C (PLC) inhibitor, PP2, Src family protein inhibitor, SB202190, p38 MAPK inhibitor, and BAY-11-7085, NF-kB inhibitor. This study also demonstrates that all-trans retinoic acid suppresses spontaneous apoptosis, similar to the mechanism of inhibition exhibited by 9CRA. Phosphorylation of p38 MAPK decreases by 9CRA treatment. $Ik-B{\alpha}$ is degraded until 30 minutes after a time-dependent 9CRA treatment, but degradation can be inhibited by Ly 294002. These results indicate that 9CRA decreases p38 MAPK activation, induces NF-kB activation via PI-3 kinase, and also blocks cleavage of caspase 3. As these findings suggest, 9CRA has a molecular mechanism which may help pro-inflammatory response by blocking neutrophil apoptosis.

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