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Sample records for circulating neutrophil numbers

  1. Transcriptome kinetics of circulating neutrophils during human experimental endotoxemia.

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    Stan de Kleijn

    Full Text Available Polymorphonuclear cells (neutrophils play an important role in the systemic inflammatory response syndrome and the development of sepsis. These cells are essential for the defense against microorganisms, but may also cause tissue damage. Therefore, neutrophil numbers and activity are considered to be tightly regulated. Previous studies have investigated gene transcription during experimental endotoxemia in whole blood and peripheral blood mononuclear cells. However, the gene transcription response of the circulating pool of neutrophils to systemic inflammatory stimulation in vivo is currently unclear. We examined neutrophil gene transcription kinetics in healthy human subjects (n = 4 administered a single dose of endotoxin (LPS, 2 ng/kg iv. In addition, freshly isolated neutrophils were stimulated ex vivo with LPS, TNFα, G-CSF and GM-CSF to identify stimulus-specific gene transcription responses. Whole transcriptome microarray analysis of circulating neutrophils at 2, 4 and 6 hours after LPS infusion revealed activation of inflammatory networks which are involved in signaling of TNFα and IL-1α and IL-1β. The transcriptome profile of inflammatory activated neutrophils in vivo reflects extended survival and regulation of inflammatory responses. These changes in neutrophil transcriptome suggest a combination of early activation of circulating neutrophils by TNFα and G-CSF and a mobilization of young neutrophils from the bone marrow.

  2. Hidden truth of circulating neutrophils (polymorphonuclear neutrophil function in periodontally healthy smoker subjects

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    Chitra Agarwal

    2016-01-01

    Full Text Available Context: Tobacco smoking is considered to be a major risk factor associated with periodontal disease. Smoking exerts a major effect on the protective elements of the immune response, resulting in an increase in the extent and severity of periodontal destruction. Aims: The aim of the present study was to assess viability and phagocytic function of neutrophils in circulating blood of the smokers and nonsmokers who are periodontally healthy. Settings and Design: Two hundred subjects in the mean range of 20–30 years of age were included in the study population. It was a retrospective study carried out for 6 months. Materials and Methods: Two hundred subjects were divided into four groups: 50 nonsmokers, 50 light smokers (15 cigarettes/day. Full mouth plaque index, sulcus bleeding index, and probing depths were measured. Percentage viability of circulating neutrophils and average number of phagocytosed Candida albicans were recorded. Statistical Analysis Used: Means and standard deviations were calculated from data obtained within the groups. Comparison between the smokers and nonsmokers was performed by Kruskal–Wallis ANOVA analysis. Comparison between smoker groups was performed using Mann–Whitney–Wilcoxon test. Results: Percentage viability of neutrophils was significantly less in heavy smokers (66.9 ± 4.0, moderate (76.6 ± 4.2, light smokers (83.1 ± 2.5 as compared to nonsmokers (92.3 ± 2.6 (P < 0.01. The ability of neutrophils to phagocytose, i.e., mean particle number was significantly less in light smokers (3.5 ± 0.5, moderate smokers (2.3 ± 0.5, and heavy smokers (1.4 ± 0.5 compared to nonsmokers (4.9 ± 0.7 (P < 0.01 with evidence of dose-response effect. Conclusions: Smoking significantly affects neutrophils viability and phagocytic function in periodontally healthy population.

  3. Circulating platelet-neutrophil complexes are important for subsequent neutrophil activation and migration.

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    Kornerup, Kristin N; Salmon, Gary P; Pitchford, Simon C; Liu, Wai L; Page, Clive P

    2010-09-01

    Previous studies in our laboratory have shown that platelets are essential for the migration of eosinophils into the lungs of allergic mice, and that this is dependent on the functional expression of platelet P-selectin. We sought to investigate whether the same is true for nonallergic, acute inflammatory stimuli administered to distinct anatomic compartments. Neutrophil trafficking was induced in two models, namely zymosan-induced peritonitis and LPS-induced lung inflammation, and the platelet dependence of these responses investigated utilizing mice rendered thrombocytopenic. The relative contribution of selectins was also investigated. The results presented herein clearly show that platelet depletion (>90%) significantly inhibits neutrophil recruitment in both models. In addition, we show that P-selectin glycoprotein ligand-1, but not P-selectin, is essential for neutrophil recruitment in mice in vivo, thus suggesting the existence of different regulatory mechanisms for the recruitment of leukocyte subsets in response to allergic and nonallergic stimuli. Further studies in human blood demonstrate that low-dose prothrombotic and pro-inflammatory stimuli (CCL17 or CCL22) synergize to induce platelet and neutrophil activation, as well as the formation of platelet-neutrophil conjugates. We conclude that adhesion between platelets and neutrophils in vivo is an important event in acute inflammatory responses. Targeting this interaction may be a successful strategy for inflammatory conditions where current therapy fails to provide adequate treatment.

  4. The axonal repellent, Slit2, inhibits directional migration of circulating neutrophils.

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    Tole, Soumitra; Mukovozov, Ilya M; Huang, Yi-Wei; Magalhaes, Marco A O; Yan, Ming; Crow, Min Rui; Liu, Guang Ying; Sun, Chun Xiang; Durocher, Yves; Glogauer, Michael; Robinson, Lisa A

    2009-12-01

    In inflammatory diseases, circulating neutrophils are recruited to sites of injury. Attractant signals are provided by many different chemotactic molecules, such that blockade of one may not prevent neutrophil recruitment effectively. The Slit family of secreted proteins and their transmembrane receptor, Robo, repel axonal migration during CNS development. Emerging evidence shows that by inhibiting the activation of Rho-family GTPases, Slit2/Robo also inhibit migration of other cell types toward a variety of chemotactic factors in vitro and in vivo. The role of Slit2 in inflammation, however, has been largely unexplored. We isolated primary neutrophils from human peripheral blood and mouse bone marrow and detected Robo-1 expression. Using video-microscopic live cell tracking, we found that Slit2 selectively impaired directional migration but not random movement of neutrophils toward fMLP. Slit2 also inhibited neutrophil migration toward other chemoattractants, namely C5a and IL-8. Slit2 inhibited neutrophil chemotaxis by preventing chemoattractant-induced actin barbed end formation and cell polarization. Slit2 mediated these effects by suppressing inducible activation of Cdc42 and Rac2 but did not impair activation of other major kinase pathways involved in neutrophil migration. We further tested the effects of Slit2 in vivo using mouse models of peritoneal inflammation induced by sodium periodate, C5a, and MIP-2. In all instances, Slit2 reduced neutrophil recruitment effectively (PSlit2 potently inhibits chemotaxis but not random motion of circulating neutrophils and point to Slit2 as a potential new therapeutic for preventing localized inflammation.

  5. Nerve growth factor induced hyperalgesia in the rat hind paw is dependent on circulating neutrophils.

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    Bennett, G; al-Rashed, S; Hoult, J R; Brain, S D

    1998-09-01

    The mechanisms by which nerve growth factor (NGF) induces thermal hyperalgesia and neutrophil accumulation have been investigated in the rat. Thermal nociceptive thresholds in rat hind paw were measured as the time taken for paw withdrawal from a heat source and neutrophil accumulation was measured in hind paw and dorsal skin samples using a myeloperoxidase assay. NGF (23-80 pmol intraplantar (i.pl.) injection) induced a significant (P NGF (40 pmol). In dorsal skin, where multiple samples can be assessed, intradermal (i.d.) NGF was 10-30 times less potent than interleukin-1beta in inducing neutrophil accumulation. The 5-lipoxygenase inhibitor ZM230487 (10 nmol co-injected with NGF) significantly attenuated neutrophil accumulation and hyperalgesia induced by NGF; unlike the histamine and 5-hydroxytryptamine antagonists (mepyramine and methysergide) which were without effect at the times measured. Furthermore, depletion of circulating neutrophils (using a rabbit anti-rat neutrophil antibody) abolished NGF induced hyperalgesia. These results indicate that neutrophils, which accumulate in response to a 5-lipoxygenase product, play a crucial role in NGF-induced hyperalgesia.

  6. A gender difference in circulating neutrophils in malnourished patients with COPD

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    Sven Larsson

    2011-01-01

    Full Text Available Sven Larsson1, Anita Nordenson1, Pernilla Glader1, Shigemi Yoshihara2, Anders Lindén1, Frode Slinde31Department of Internal Medicine/Respiratory Medicine and Allergology, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Sweden; 2Department of Pediatrics, Dokkyo Medical University, Tochigi, Japan; 3Department of Clinical Nutrition, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, SwedenBackground: Circulating markers of inflammation in chronic obstructive pulmonary disease (COPD may correlate to disease progression and extrapulmonary complications such as malnourishment. However, surprisingly little is known about gender-related differences for circulating inflammatory markers in COPD.Purpose: To characterize differences in circulating markers of inflammation in malnourished female and male patients with COPD.Subjects: Thirty female and 11 male patients with a clinical diagnosis of COPD and malnourishment were examined. A group of control subjects without evidence of COPD was recruited for comparison of some variables.Methods: Blood samples were drawn, and the following parameters were studied: leukocytes and differential counts, C-reactive protein (CRP, tumor necrosis factor-α, interleukin (IL-6 and IL-8, myeloperoxidase (MPO, neutrophil elastase (NE, intracellular adhesion molecule-1, vascular endothelial adhesion molecule-1, and E-selectin.Results: The mean neutrophil concentration was significantly (P = 0.019 higher in female (4.5 × 109/L than in male patients with COPD (3.5 × 109/L and significantly higher than in female control subjects (3.1 × 109/L (P , 0.01, n = 85. The mean CRP values were considerably higher in female (4.9 mg/mL than in male patients with COPD (1.5 mg/mL, but the difference was not statistically significant (P = 0.20. The mean concentrations of IL-6 and IL-8 tended to be higher in female than in male patients with COPD, but these differences did not reach statistical

  7. The Invertibility, Explicit Determinants, and Inverses of Circulant and Left Circulant and g-Circulant Matrices Involving Any Continuous Fibonacci and Lucas Numbers

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    Zhaolin Jiang

    2014-01-01

    Full Text Available Circulant matrices play an important role in solving delay differential equations. In this paper, circulant type matrices including the circulant and left circulant and g-circulant matrices with any continuous Fibonacci and Lucas numbers are considered. Firstly, the invertibility of the circulant matrix is discussed and the explicit determinant and the inverse matrices by constructing the transformation matrices are presented. Furthermore, the invertibility of the left circulant and g-circulant matrices is also studied. We obtain the explicit determinants and the inverse matrices of the left circulant and g-circulant matrices by utilizing the relationship between left circulant, g-circulant matrices and circulant matrix, respectively.

  8. On the clique number of integral circulant graphs

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    Bašić, Milan

    2011-01-01

    The concept of gcd-graphs is introduced by Klotz and Sander, which arises as a generalization of unitary Cayley graphs. The gcd-graph $X_n (d_1,...,d_k)$ has vertices $0,1,...,n-1$, and two vertices $x$ and $y$ are adjacent iff $\\gcd(x-y,n)\\in D = \\{d_1,d_2,...,d_k\\}$. These graphs are exactly the same as circulant graphs with integral eigenvalues characterized by So. In this paper we deal with the clique number of integral circulant graphs and investigate the conjecture proposed in \\cite{klotz07} that clique number divides the number of vertices in the graph $X_n (D)$. We completely solve the problem of finding clique number for integral circulant graphs with exactly one and two divisors. For $k \\geqslant 3$, we construct a family of counterexamples and disprove the conjecture in this case.

  9. Expression of CD64 on Circulating Neutrophils Favoring Systemic Inflammatory Status in Erythema Nodosum Leprosum

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    Prata, Rhana Berto da Silva; Barbosa, Mayara Garcia de Mattos; Mendes, Mayara Abud; Brandão, Sheila Santos; Amadeu, Thaís Porto; Rodrigues, Luciana Silva; Ferreira, Helen; Costa, Fabrício da Mota Ramalho; dos Santos, Jessica Brandão; Pacheco, Fabiana dos Santos; Machado, Alice de Miranda; Nery, José Augusto da Costa; Hacker, Mariana de Andrea; Sales, Anna Maria; Pinheiro, Roberta Olmo; Sarno, Euzenir Nunes

    2016-01-01

    Erythema Nodosum Leprosum (ENL) is an immune reaction in leprosy that aggravates the patient´s clinical condition. ENL presents systemic symptoms of an acute infectious syndrome with high leukocytosis and intense malaise clinically similar to sepsis. The treatment of ENL patients requires immunosuppression and thus needs to be early and efficient to prevent both disabilities and permanent nerve damage. Some patients experience multiple episodes of ENL and prolonged use of immunosuppressive drugs may lead to serious adverse effects. Thalidomide treatment is extremely effective at ameliorating ENL symptoms. Several mechanisms have been proposed to explain the efficacy of thalidomide in ENL, including the inhibition of TNF production. Given its teratogenicity, thalidomide is prohibitive for women of childbearing age. A rational search for molecular targets during ENL episodes is essential to better understand the disease mechanisms involved, which may also lead to the discovery of new drugs and diagnostic tests. Previous studies have demonstrated that IFN-γ and GM-CSF, involved in the induction of CD64 expression, increase during ENL. The aim of the present study was to investigate CD64 expression during ENL and whether thalidomide treatment modulated its expression. Leprosy patients were allocated to one of five groups: (1) Lepromatous leprosy, (2) Borderline leprosy, (3) Reversal reaction, (4) ENL, and (5) ENL 7 days after thalidomide treatment. The present study demonstrated that CD64 mRNA and protein were expressed in ENL lesions and that thalidomide treatment reduced CD64 expression and neutrophil infiltrates—a hallmark of ENL. We also showed that ENL blood neutrophils exclusively expressed CD64 on the cell surface and that thalidomide diminished overall expression. Patient classification based on clinical symptoms found that severe ENL presented high levels of neutrophil CD64. Collectively, these data revealed that ENL neutrophils express CD64, presumably

  10. Explicit Determinants of the RFPrLrR Circulant and RLPrFrL Circulant Matrices Involving Some Famous Numbers

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    Tingting Xu

    2014-01-01

    Full Text Available Circulant matrices may play a crucial role in solving various differential equations. In this paper, the techniques used herein are based on the inverse factorization of polynomial. We give the explicit determinants of the RFPrLrR circulant matrices and RLPrFrL circulant matrices involving Fibonacci, Lucas, Pell, and Pell-Lucas number, respectively.

  11. BIIL 284 reduces neutrophils numbers but increases P. aeruginosa bacteraemia and inflammation in mouse lungs

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    Döring, Gerd; Bragonzi, Alessandra; Paroni, Moira; Aktürk, Firdevs-Fatma; Cigana, Cristina; Schmidt, Annika; Gilpin, Deirdre; Heyder, Susanne; Born, Torsten; Smaczny, Christina; Kohlhäufl, Martin; Wagner, Thomas O. F.; Loebinger, Michael R.; Bilton, Diana; Tunney, Michael M.; Elborn, J. Stuart; Pier, Gerald B.; Konstan, Michael W.; Ulrich, Martina

    2014-01-01

    Background A clinical study to investigate the leukotriene B4 (LTB4)-receptor antagonist BIIL 284 in cystic fibrosis (CF) patients was prematurely terminated due to a significantly increased risk of adverse pulmonary events. We aimed to establish the effect of BIIL284 in models of Pseudomonas aeruginosa lung infection, thereby contributing to a better understanding of what could have led to adverse pulmonary events in CF patients. Methods P. aeruginosa DNA in the blood of CF patients during and after acute pulmonary exacerbations and in stable patients with non-CF bronchiectasis (NCFB) and healthy individuals was assessed by PCR. The effect of BIIL 284 treatment was tested in an agar beads murine model of Pseudomonas aeruginosa lung infection. Bacterial count and inflammation were evaluated in lung and other organs. Result Most CF patients (98%) and all patients with NCFB and healthy individuals had negative P. aeruginosa DNA in their blood. Similarly, the P. aeruginosa-infected mice showed bacterial counts in the lung but not blood or spleen. BIIL 284 treatment decreased pulmonary neutrophils and increased P. aeruginosa numbers in mouse lungs leading to significantly higher bacteremia rates and lung inflammation compared to placebo treated animals. Conclusions Decreased airway neutrophils induced lung proliferation and severe bacteraemia in a murine model of P. aeruginosa lung infection. These data suggest that caution should be taken when administering anti-inflammatory compounds to patients with bacterial infections. PMID:24183915

  12. The Dichromatic Number of Infinite Families of Circulant Tournaments

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    Javier Nahid

    2017-02-01

    Full Text Available The dichromatic number dc(D of a digraph D is defined to be the minimum number of colors such that the vertices of D can be colored in such a way that every chromatic class induces an acyclic subdigraph in D. The cyclic circulant tournament is denoted by T=C→2n+1(1,2,…,n$T = \\overrightarrow C _{2n + 1} (1,2, \\ldots ,n$, where V (T = ℤ2n+1 and for every jump j ∈ {1, 2, . . . , n} there exist the arcs (a, a + j for every a ∈ ℤ2n+1. Consider the circulant tournament C→2n+1〈k〉$\\overrightarrow C _{2n + 1} \\left\\langle k \\right\\rangle $ obtained from the cyclic tournament by reversing one of its jumps, that is, C→2n+1 〈k〉$\\overrightarrow C _{2n + 1} \\left\\langle k \\right\\rangle $ has the same arc set as C→2n+1(1,2,…,n$\\overrightarrow C _{2n + 1} (1,2, \\ldots ,n$ except for j = k in which case, the arcs are (a, a − k for every a ∈ ℤ2n+1. In this paper, we prove that dc(C→2n+1 〈k〉∈{2,3,4}$dc ( {\\overrightarrow C _{2n + 1} \\left\\langle k \\right\\rangle } \\in \\{ 2,3,4\\}$ for every k ∈ {1, 2, . . . , n}. Moreover, we classify which circulant tournaments C→2n+1 〈k〉$\\overrightarrow C _{2n + 1} \\left\\langle k \\right\\rangle$ are vertex-critical r-dichromatic for every k ∈ {1, 2, . . . , n} and r ∈ {2, 3, 4}. Some previous results by Neumann-Lara are generalized.

  13. Hypoxia Mediated Release of Endothelial Microparticles and Increased Association of S100A12 with Circulating Neutrophils

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    Rebecca V. Vince

    2009-01-01

    Full Text Available Microparticles are released from the endothelium under normal homeostatic conditions and have been shown elevated in disease states, most notably those characterised by endothelial dysfunction. The endothelium is sensitive to oxidative stress/status and vascular cell adhesion molecule-1 (VCAM-1 expression is upregulated upon activated endothelium, furthermore the presence of VCAM-1 on microparticles is known. S100A12, a calcium binding protein part of the S100 family, is shown to be present on circulating leukocytes and is thought a sensitive marker to local inflammatory process, which may be driven by oxidative stress. Eight healthy males were subjected to breathing hypoxic air (15% O2, approximately equivalent to 3000 metres altitude for 80 minutes in a temperature controlled laboratory and venous blood samples were processed immediately for VCAM-1 microparticles (VCAM-1 MP and S100A12 association with leukocytes by flow cytometry. A pre-hypoxic blood sample was used for comparison. Both VCAM-1 MP and S100A12 association with neutrophils were significantly elevated post hypoxic breathing later declining to levels observed in the pre-test samples. A similar trend was observed in both cases and a correlation may exist between these two markers in response to hypoxia. These data offer evidence using novel markers of endothelial and circulating blood responses to hypoxia.

  14. Serum IL8 and mRNA level of CD11b in circulating neutrophils are increased in clinically amyopathic dermatomyositis with active interstitial lung disease.

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    Zou, Jing; Chen, Jie; Yan, Qingran; Guo, Qiang; Bao, Chunde

    2016-01-01

    The objective of this study is to assess serum IL8 and the potential activity of circulating neutrophils on relative messenger RNA (mRNA) levels and their relationship with disease activity in clinically amyopathic dermatomyositis (CADM) associated with interstitial lung disease (ILD). We studied 18 CADM patients and compared them with 18 classic dermatomyositis (DM) patients and 18 healthy control subjects. Serum IL8 level and mRNA expressions of neutrophils (chemokine (C-X-C motif) receptor 1 (CXCR1), cluster of differentiation molecule 11b (CD11b), cluster of differentiation 64 (CD64), myeloid cell leukemia 1 (MCL1), interleukin-18 (IL18)) were detected. The overproduction of serum IL8 level was most significant in the CADM group with active period. The mRNA expressions of CD11b, IL18, and MCL1 were greatly increased in the neutrophils in patients with CADM compared with DM or healthy controls. Up-expressions of CD11b, IL18, and MCL1 were detected in the neutrophils in CADM patients of active period compared with remission period. A positive correlation was found between CD11b mRNA level and high-resolution computed tomography (HRCT) score, in CADM associated with ILD. Serum IL8 level and mRNA levels of CD11b, MCL1, and IL18 in circulating neutrophils are related with the disease activity of CADM-ILD. The mRNA level of CD11b is positively correlated with HRCT score in CADM-ILD.

  15. Neutrophils, from marrow to microbes

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    Borregaard, Niels

    2010-01-01

    . Neutrophils circulate in the blood as dormant cells. At sites of infection, endothelial cells capture bypassing neutrophils and guide them through the endothelial cell lining whereby the neutrophils are activated and tuned for the subsequent interaction with microbes. Once in tissues, neutrophils kill...... microorganisms by microbicidal agents liberated from granules or generated by metabolic activation. As a final act, neutrophils can extrude stands of DNA with bactericidal proteins attached that act as extracellular traps for microorganisms....

  16. The effect of clomethiazole on plasma concentrations of interleukin-6, -8, -1beta, tumor necrosis factor-alpha, and neutrophil adhesion molecule expression during experimental extracorporeal circulation.

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    Harmon, D

    2012-02-03

    Clomethiazole (CMZ), a neuroprotective drug, has antiinflammatory actions. We investigated the effects of CMZ administration on plasma concentrations of interleukin (IL)-6, IL-8, IL-1beta, tumor necrosis factor-alpha, and neutrophil adhesion molecule expression during experimental extracorporeal circulation. Five healthy volunteers each donated 500 mL of blood, which was subsequently divided into equal portions. Identical extracorporeal circuits were simultaneously primed with donated blood (250 mL) and circulated for 2 h at 37 degrees C. CMZ was added to 1 of the circuits of each pair to achieve a total plasma concentration of 40 micro mol\\/L. Blood samples were withdrawn at (i) donation, (ii) immediately after addition of CMZ, and at (iii) 30, 60, 90, and 120 min after commencing circulation. Plasma concentrations of IL-6, IL-8, and tumor necrosis factor-alpha were less in the CMZ group compared with control after 60 min of circulation (2.2 [0.3] versus 3.2 [0.4], 14.9 [4.8] versus 21.9 [18.4], 63.3 [43.5] versus 132.2 [118.9] pg\\/mL, respectively, P < 0.05). After 120 min of circulation, neutrophils from CMZ-treated circuits showed significantly less CD18 expression compared with control (237.5 [97.4] versus 280.5 [111.5], P = 0.03). The addition of CMZ to experimental extracorporeal circuits decreases the inflammatory response. This effect may be of clinical benefit by decreasing inflammatory-mediated neurological injury during cardiopulmonary bypass. IMPLICATIONS: Enhancement of gamma-aminobutyric acid(A)-mediated effects by clomethiazole (CMZ) and associated neuroprotection has been established in animal models of cerebral ischemia. In an ex vivo study, we demonstrated antiinflammatory activity of CMZ in experimental extracorporeal circulation. This represents a potential neuroprotective mechanism of CMZ in patients undergoing coronary artery bypass surgery.

  17. Isolation and number of circulated primordial germ cells (circulated-PGCs on stages of embryonic development of Gaok chicken

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    Kostaman T

    2013-03-01

    Full Text Available Avian primordial germ cell (PGCs show a unique migration pathway during early development. During the early embryonic development, as soon as the formation of blood vessels, PGCs enter the circulatory system and migrate to the gonadal primordial. The aim of this study was to examine the number of circulated-PGCs from Gaok chicken at different developmental stages of embryo. One hundred fertile eggs were divided into 5 groups and incubated in a portable incubator at 38oC and humidity 60%. Hatching was set according to the embryonic development stage between 14-18. The blood collection was done through the dorsal aorta using micropipette under microscope. The collected blood was grouped based on the embryonic stages and placed on a 1.5 ml eppendorf tube which had been filled with 1.000 µl of Calcium and Magnesium-free phosphate buffered saline (PBS -. The PGCs were then purified using nycodenz density gradient centrifugation. The results showed that the average number of circulated-PGCs per embryo from Gaok chicken were significantly affected by the stage of embryonic development (P < 0.05. The number of circulated-PGCs at stages 14, 15, 16, 17 and 18 were 42.8 ± 8.9, 51.0 ± 5.8, 37.6 ± 5.9, 32.8 ± 3.6 and 32.6 ± 3.2, respectively. However, the number of circulated-PGCs was no different between stage of 17 and 18. At Gaok chicken, the number of circulated-PGCs reach the peak at stage 15, it is recommended that collection of PGCs embryonic chicken from blood circulation was the best on stage 15. This information is useful in efficiency production of germline chimera and to preserve PGCs of other Indonesian native chicken.

  18. Prediction of cloud droplet number in a general circulation model

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    Ghan, S.J.; Leung, L.R. [Pacific Northwest National Lab., Richland, WA (United States)

    1996-04-01

    We have applied the Colorado State University Regional Atmospheric Modeling System (RAMS) bulk cloud microphysics parameterization to the treatment of stratiform clouds in the National Center for Atmospheric Research Community Climate Model (CCM2). The RAMS predicts mass concentrations of cloud water, cloud ice, rain and snow, and number concnetration of ice. We have introduced the droplet number conservation equation to predict droplet number and it`s dependence on aerosols.

  19. The Fibonacci numbers of certain subgraphs of circulant graphs

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    Loiret Alejandría Dosal-Trujillo

    2015-11-01

    We prove that the total number of independent vertex sets of the family of graphs Cn[r] for all n≥r+1, and for several subgraphs of this family is completely determined by some sequences which are constructed recursively like the Fibonacci and Lucas sequences, even more, these new sequences generalize the Fibonacci and Lucas sequences.

  20. Testosterone replacement therapy can increase circulating endothelial progenitor cell number in men with late onset hypogonadism.

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    Liao, C-H; Wu, Y-N; Lin, F-Y; Tsai, W-K; Liu, S-P; Chiang, H-S

    2013-07-01

    Circulating endothelial progenitor cells (EPCs) are bone marrow-derived cells required for endothelial repair. A low EPC number can be considered as an independent predictor of endothelial dysfunction and future cardiovascular events. Recent evidence shows that patients with hypogonadal symptoms without other confounding risk factors have a low number of circulating progenitor cells (PCs) and EPCs, thus highlighting the role of testosterone in the proliferation and differentiation of EPCs. Here, we investigate if testosterone replacement therapy (TRT) can increase circulating EPC number in men with late onset hypogonadism. Forty-six men (age range, 40-73 years; mean age, 58.3 years) with hypogonadal symptoms were recruited, and 29 men with serum total testosterone (TT) levels less than 350 ng/dL received TRT using transdermal testosterone gel (Androgel; 1% testosterone at 5 g/day) for 12 months. Circulating EPC numbers (per 100 000 monocytes) were calculated using flow cytometry. There was no significant association between serum TT levels and the number of circulating EPCs before TRT. Compared with the number of mean circulating EPCs at baseline (9.5 ± 6.2), the number was significantly higher after 3 months (16.6 ± 11.1, p = 0.027), 6 months (20.3 ± 15.3, p = 0.006) and 12 months (27.2 ± 15.5, p = 0.017) of TRT. Thus, we conclude that serum TT levels before TRT are not significantly associated with the number of circulating EPCs in men with late onset hypogonadism. However, TRT can increase the number of circulating EPCs, which implies the benefit of TRT on endothelial function in hypogonadal men.

  1. The Explicit Identities for Spectral Norms of Circulant-Type Matrices Involving Binomial Coefficients and Harmonic Numbers

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    Jianwei Zhou

    2014-01-01

    Full Text Available The explicit formulae of spectral norms for circulant-type matrices are investigated; the matrices are circulant matrix, skew-circulant matrix, and g-circulant matrix, respectively. The entries are products of binomial coefficients with harmonic numbers. Explicit identities for these spectral norms are obtained. Employing these approaches, some numerical tests are listed to verify the results.

  2. Increased secretion of pro-inflammatory cytokines by circulating polymorphonuclear neutrophils and regulation by interleukin 10 during intestinal inflammation

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    Nikolaus, S; Bauditz, J; Gionchetti, P; Witt, C; Lochs, H; Schreiber, S.

    1998-01-01

    Background—Concentrations of pro-inflammatory cytokines are increased in the intestinal mucosa of patients with active inflammatory bowel disease (IBD). Polymorphonuclear neutrophil granulocytes (PMN) are the most abundant cell type in intestinal lesions in IBD. Interleukin 10 (IL-10) is an important contra-inflammatory cytokine which induces downregulation of pro-inflammatory cytokines. 
Aims—To investigate whether PMN from patients with IBD or infectious colitis, respec...

  3. On the norms of r-circulant matrices with generalized Fibonacci numbers

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    Amara Chandoul

    2017-01-01

    Full Text Available In this paper, we obtain a generalization of [6, 8]. Firstly, we consider the so-called r-circulant matrices with generalized Fibonacci numbers and then found lower and upper bounds for the Euclidean and spectral norms of these matrices. Afterwards, we present some bounds for the spectral norms of Hadamard and Kronecker product of these matrices.

  4. Neutrophils, from marrow to microbes

    DEFF Research Database (Denmark)

    Borregaard, Niels

    2010-01-01

    . Neutrophils circulate in the blood as dormant cells. At sites of infection, endothelial cells capture bypassing neutrophils and guide them through the endothelial cell lining whereby the neutrophils are activated and tuned for the subsequent interaction with microbes. Once in tissues, neutrophils kill......Neutrophils are produced in the bone marrow from stem cells that proliferate and differentiate to mature neutrophils fully equipped with an armory of granules. These contain proteins that enable the neutrophil to deliver lethal hits against microorganisms, but also to cause great tissue damage...... microorganisms by microbicidal agents liberated from granules or generated by metabolic activation. As a final act, neutrophils can extrude stands of DNA with bactericidal proteins attached that act as extracellular traps for microorganisms....

  5. Invertibility and Explicit Inverses of Circulant-Type Matrices with k-Fibonacci and k-Lucas Numbers

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    Zhaolin Jiang

    2014-01-01

    Full Text Available Circulant matrices have important applications in solving ordinary differential equations. In this paper, we consider circulant-type matrices with the k-Fibonacci and k-Lucas numbers. We discuss the invertibility of these circulant matrices and present the explicit determinant and inverse matrix by constructing the transformation matrices, which generalizes the results in Shen et al. (2011.

  6. Number of Spanning Trees of Circulant Graphs C6n and their Applications

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    S. N. Daoud

    2012-01-01

    Full Text Available Problem statement: The number of spanning trees of a graph G is usually denoted by τ(G. A circulant graph with n vertices and k jumps is Cn (a1,…..,ak. Approach: In this study the number τ(G of spanning trees of the circulant graphs C6n with some non-fixed jumps such as C6n (1, n, C6n (1, n, 2n, C6n (1, n, 3n, C6n (1, 2n 3n, C6n (1, n, 2n, 3n, are evaluated using Chebyshev polynomials. A large number of theorems of number of the spanning trees of circulate graphs C12n are obtained. Results: The number τ(G of spanning trees of the circulant graphs C6n(1, n, C6n(1, n, 2n, C6n(1, n, 3n, C6n(1, 2n, 3n, C6n(1, n, 2n, 3n, C12n(1, 2n, 3n, C12n(1, 3n, 6n, C12n(1, 3n, 4n, C12n(1, 2n, 3n, 4n, C12n(1, 2n, 3n, 6n, C12n(1, 3n, 4n, 6n and C12n(1, 2n, 3n, 4n, 6n are evaluated. Conclusion: The number of spanning trees τ(G in graphs (networks is an important invariant. The evaluation of this number and analyzing its behavior is not only interesting from a mathematical (computational perspective, but also, it is an important measure of reliability of a network and designing electrical circuits. Some computationally hard problems such as the travelling salesman problem can be solved approximately by using spanning trees. Due to the high dependence of the network design and reliability on the graph theory we introduced the following important theorems and their proofs.

  7. Isolation of Mouse Neutrophils.

    Science.gov (United States)

    Swamydas, Muthulekha; Luo, Yi; Dorf, Martin E; Lionakis, Michail S

    2015-08-03

    Neutrophils represent the first line of defense against bacterial and fungal pathogens. Indeed, patients with inherited and acquired qualitative and quantitative neutrophil defects are at high risk for developing bacterial and fungal infections and suffering adverse outcomes from these infections. Therefore, research aiming at defining the molecular factors that modulate neutrophil effector function under homeostatic conditions and during infection is essential for devising strategies to augment neutrophil function and improve the outcome of infected individuals. This unit describes a reproducible density gradient centrifugation-based protocol that can be applied in any laboratory to harvest large numbers of highly enriched and highly viable neutrophils from the bone marrow of mice both at the steady state and following infection with Candida albicans as described in UNIT. In another protocol, we also present a method that combines gentle enzymatic tissue digestion with a positive immunomagnetic selection technique or Fluorescence-activated cell sorting (FACS) to harvest highly pure and highly viable preparations of neutrophils directly from mouse tissues such as the kidney, the liver or the spleen. Finally, methods for isolating neutrophils from mouse peritoneal fluid and peripheral blood are included. Mouse neutrophils isolated by these protocols can be used for examining several aspects of cellular function ex vivo including pathogen binding, phagocytosis and killing, neutrophil chemotaxis, oxidative burst, degranulation and cytokine production, and for performing neutrophil adoptive transfer experiments.

  8. Immunosenescence of Polymorphonuclear Neutrophils

    Directory of Open Access Journals (Sweden)

    Inga Wessels

    2010-01-01

    Full Text Available All immune cells are affected by aging, contributing to the high susceptibility to infections and increased mortality observed in the elderly. The effect of aging on cells of the adaptive immune system is well documented. In contrast, knowledge concerning age-related defects of polymorphonuclear neutrophils (PMN is limited. During the past decade, it has become evident that in addition to their traditional role as phagocytes, neutrophils are able to secrete a wide array of immunomodulating molecules. Their importance is underlined by the finding that genetic defects that lead to neutropenia increase susceptibility to infections. Whereas there is consistence about the constant circulating number of PMN throughout aging, the abilities of tissue infiltration, phagocytosis, and oxidative burst of PMN from aged donors are discussed controversially. Furthermore, there are numerous discrepancies between in vivo and in vitro results, as well as between results for murine and human PMN. Most of the reported functional changes can be explained by defective signaling pathways, but further research is required to get a detailed insight into the underlying molecular mechanisms. This could form the basis for drug development in order to prevent or treat age-related diseases, and thus to unburden the public health systems.

  9. Relationship between athlete’s men cortisol with leukocytosis and Neutrophils numbers after exercise in cold, warm and normal temperatures conditions

    Directory of Open Access Journals (Sweden)

    Abbas Ali Gaeini

    2012-02-01

    Full Text Available Background & Objective: Exercise and extreme environments, causes hormonal and immune systems changes. Therefore, the purpose of this study was evaluating the relationship between cortisol and leukocytosis and Neutrophil numbers after exercise in cold, warm and natural temperatures. Materials & Methods: Ten young male athletes ran on a treadmill for an hour at the intensity of %60VO2max in three temperature conditions of normal (22±1˚c, 50±5RH, cold (3±1˚c, 50±2RH and warm (35±1˚c, 50±5RH. Blood samples were collected before and immediately after exercise. The total numbers of leukocytes and neutrophils were computed using Sysmex Kohden Nihon and serum cortisol concentrations determined by using ELISA. For comparing of data before and after exercise used from Paired T-test and for examine the relationship between variables used from Pearson Correlation Coefficient test. Results: The total leukocytes and the cortisol levels increased significantly after the exercise, in all the conditions (p<0.0001. Also, the number of neutrophils increased significantly after exercise in cold (p=0.001 and normal (p=0.001 environments. In addition, a significant relation was observed between cortisol levels and leukocytosis (R=0.783, P=0.007 and R=0.813, P=0.004 and between cortisol and Neutrophils after exercising in the natural and warm environment (R=0.806, P=0.005 and R=0.852, P=0.002. But, there was no significant relationship between these values after exercise in cold (R=0.63, P=0.051 and R=0.554, P=0.096. Conclusion: Exercise in all the three conditions causes the release of cortisol through stimulating the hypothalamic-pituitary- adrenal (HPA and effect of cortisol receptor on immune cells could cause increase Neutrophils and leukocytosis. It seems that elevation of cortisol concentration during exercise in warm and natural environments is responsible for increase Neutrophils and leukocytosis. Moreover, during exercise in cold environments

  10. Kinematic vorticity number – a tool for estimating vortex sizes and circulations

    Directory of Open Access Journals (Sweden)

    Lisa Schielicke

    2016-02-01

    Full Text Available The influence of extratropical vortices on a global scale is mainly characterised by their size and by the magnitude of their circulation. However, the determination of these properties is still a great challenge since a vortex has no clear delimitations but is part of the flow field itself. In this work, we introduce a kinematic vortex size determination method based on the kinematic vorticity number Wk to atmospheric flows. Wk relates the local rate-of-rotation to the local rate-of-deformation at every point in the field and a vortex core is identified as a simply connected region where the rotation prevails over the deformation. Additionally, considering the sign of vorticity in the extended Wk-method allows to identify highs and lows in different vertical layers of the atmosphere and to study vertical as well as horizontal vortex interactions. We will test the Wk-method in different idealised -D (superposition of two lows/low and jet and real -D flow situations (winter storm affecting Europe and compare the results with traditional methods based on the pressure and the vorticity fields. In comparison to these traditional methods, the Wk-method is able to extract vortex core sizes even in shear-dominated regions that occur frequently in the upper troposphere. Furthermore, statistics of the size and circulation distributions of cyclones will be given. Since the Wk-method identifies vortex cores, the identified radii are subsynoptic with a broad peak around 300–500 km at the 1000 hPa level. However, the total circulating area is not only restricted to the core. In general, circulations are in the order of 107 m2/s with only a few cyclones in the order of 108 m2/s.

  11. Circulating dendritic cell number and intracellular TNF-α production in women with type 2 diabetes.

    Science.gov (United States)

    Blank, Sally E; Johnson, Emily Carolyn; Weeks, Debra K; Wysham, Carol H

    2012-12-01

    Human dendritic cell (DC) subsets perform specialized functions for surveillance against bacterial and viral infections essential for the management of type 2 diabetes (T2D). Production of tumor necrosis factor-alpha (TNF-α) by DCs acts in autocrine fashion to regulate DC maturation and promotes the inflammatory response. This study was designed to compare circulating DC number and intracellular TNF-α production between post-menopausal women with T2D and healthy women. Blood samples were obtained (n = 21/group) and examined for plasma glucose and TNF-α concentrations, and dendritic cell subset immunophenotype (plasmacytoid, pDC, CD85k(ILT-3)(+)CD123(+)CD16(-)CD14(-) and myeloid, mDC, CD85k(ILT-3)(+)CD33(+)CD123(dim to neg)CD16(-)CD14(dim to neg)). Intracellular production of TNF-α was determined in unstimulated and stimulated DCs. Women with T2D had significantly (P TNF-α concentrations when compared to healthy women. Women with T2D having poor glycemic control (T2D Poor Control, HbA1c ≥ 7%) had fewer circulating pDCs than women with T2D having good glycemic control (T2D Good Control, HbA1c TNF-α in stimulated pDCs. Intracellular production of TNF-α in pDCs was significantly greater in healthy vs. T2D Poor Control (P production of TNF-α did not differ between groups. These findings indicate that TNF-α production by pDCs was reduced in women with T2D and circulating number of pDCs was associated with glycemic control.

  12. Decreased Number of Circulating Endothelial Progenitor Cells (CD133+/KDR+) in Patients with Psoriatic Arthritis.

    Science.gov (United States)

    Batycka-Baran, Aleksandra; Paprocka, Maria; Baran, Wojciech; Szepietowski, Jacek C

    2016-08-23

    Cardiovascular diseases are a major cause of mortality in patients with psoriatic arthritis (PsA), but the precise mechanism of increased cardiovascular risk is unknown. Endothelial dysfunction plays a crucial role in the development of atherosclerosis. Circulating endothelial progenitor cells (CEPCs) contribute to endothelial regeneration and their level may be affected by chronic inflammation. The aim of this study was to evaluate the number of CEPCs in patients with PsA (n = 24) compared with controls (n = 26). CEPCs were identified as CD133+/ KDR+ cells in peripheral blood, using flow cytometry. A significantly decreased number of CEPCs was observed in patients with PsA (p number of these cells was significantly, inversely correlated with the severity of skin and joint involvement (Psoriasis Area and Severity Index (PASI), DAS28) and the level of C-reactive protein. We hypothesize that the reduced number of CEPCs may indicate and contribute to the increased cardiovascular risk in patients with PsA.

  13. Changes in the number of circulating CD34+cells after eccentric exercise of the elbow flexors in relation to muscle damage

    Institute of Scientific and Technical Information of China (English)

    Ho Seong Lee; Makii Muthalib; Takayuki Akimoto; Kazunori Nosaka

    2015-01-01

    Background:It has been reported that strenuous exercise increases the number of bone marrow-derived progenitor cells such as CD34+cells in the blood, but no previous studies have investigated the changes in circulating CD34+cells following resistance exercise. This study tested the hypothesis that the number of CD34+cells in the blood would increase after eccentric exercise of the elbow flexors, but decrease in recovery, and the magnitude of the changes would be dependent on the magnitude of muscle damage. Methods:Nine men (28.0 ± 6.6 years) performed exercises consisting of 10 sets of six maximal voluntary eccentric contractions of the elbow flexors with their non-dominant arm. Six of them performed the same exercise with the same arm 4 weeks later. Changes in indirect markers of muscle damage were measured before, within 10 min after, and at 24, 48, 72, and 96 h after eccentric exercise. Differential leukocyte counts (total leukocytes, neutrophils, lymphocytes, monocytes) and CD34+cells in the blood were measured before, immediately after, and at 2, 24, 48, 72, and 96 h following the exercises. Results:After eccentric exercise, significant ( p<0.05) decreases in maximal voluntary isometric contraction torque and increases in delayed onset muscle soreness and plasma creatine kinase activity were observed. However, no significant changes in leukocytes and CD34+cells were evident. The changes in muscle damage markers were significantly ( p<0.05) smaller following the second exercise session as compared with the first exercise session, but the changes in leukocytes and CD34+cells were not significantly different between sessions. Conclusion:These results did not support the hypothesis, and showed that eccentric exercise-induced muscle damage to the elbow flexors did not influence the number of circulating CD34+cells.

  14. The effects of phototherapy on the numbers of circulating natural killer cells and T lymphocytes in psoriasis.

    LENUS (Irish Health Repository)

    Tobin, A M

    2009-04-01

    The innate immune system is believed to be important in the pathogenesis of psoriasis and natural killer (NK) have been found in increased numbers in psoriatic plaques. Alterations in the numbers of NK cells in peripheral blood have been reported. We investigated the effect of phototherapy on levels of peripheral NK cells and lymphocytes in patients with psoriasis. In nine patients whom we followed before, during and after narrowband ultraviolet B (UVB) treatment there were no differences in the numbers of circulating lymphocytes, lymphocyte subsets or cells expressing NK markers and controls. Treatment with narrowband UVB did, however, significantly lower circulating CD4 counts which gradually recovered posttreatment.

  15. Vitamin D Status in Rheumatoid Arthritis: Inflammation, Arterial Stiffness and Circulating Progenitor Cell Number.

    Directory of Open Access Journals (Sweden)

    Alberto Lo Gullo

    Full Text Available Suboptimal vitamin D status was recently acknowledged as an independent predictor of cardiovascular diseases and all-cause mortality in several clinical settings, and its serum levels are commonly reduced in Rheumatoid Arthritis (RA. Patients affected by RA present accelerated atherosclerosis and increased cardiovascular morbidity and mortality with respect to the general population. In RA, it has been reported an impairment of the number and the activity of circulating proangiogenic haematopoietic cells (PHCs, including CD34+, that may play a role in endothelial homeostasis. The purpose of the study is to investigate the association between vitamin D levels and PHCs, inflammatory markers, and arterial stiffening in patients with RA.CD34+ cells were isolated from 27 RA patients and 41 controls. Vitamin D levels, C-reactive protein (CRP, fibrinogen, pulse wave velocity (PWV, and carotid intima-media thickness (cIMT were also evaluated. CD34+ count and vitamin D levels were lower in RA patients as compared to controls, while fibrinogen, CRP, PWV and cIMT were higher in RA patients. CD34+ cell number appeared to be associated with vitamin D levels, and negatively correlated to fibrinogen and early atherosclerosis markers (PWV and cIMT; vitamin D levels appear also to be inversely associated to fibrinogen.RA patients with moderate disease activity presented with low vitamin D levels, low CD34+ cell count, increased PWV and cIMT; we found that vitamin D deficiency is associated to CD34+ cell reduction in peripheral blood, and with fibrinogen levels. This suggests that vitamin D might contribute to endothelial homeostasis in patients with RA.

  16. Reverse-migrated neutrophils regulated by JAM-C are involved in acute pancreatitis-associated lung injury.

    Science.gov (United States)

    Wu, Deqing; Zeng, Yue; Fan, Yuting; Wu, Jianghong; Mulatibieke, Tunike; Ni, Jianbo; Yu, Ge; Wan, Rong; Wang, Xingpeng; Hu, Guoyong

    2016-02-04

    Junctional adhesion molecule-C (JAM-C) plays a key role in the promotion of the reverse transendothelial migration (rTEM) of neutrophils, which contributes to the dissemination of systemic inflammation and to secondary organ damage. During acute pancreatitis (AP), systemic inflammatory responses lead to distant organ damage and typically result in acute lung injury (ALI). Here, we investigated the role of rTEM neutrophils in AP-associated ALI and the molecular mechanisms by which JAM-C regulates neutrophil rTEM in this disorder. In this study, rTEM neutrophils were identified in the peripheral blood both in murine model of AP and human patients with AP, which elevated with increased severity of lung injury. Pancreatic JAM-C was downregulated during murine experimental pancreatitis, whose expression levels were inversely correlated with both increased neutrophil rTEM and severity of lung injury. Knockout of JAM-C resulted in more severe lung injury and systemic inflammation. Significantly greater numbers of rTEM neutrophils were present both in the circulation and pulmonary vascular washout in JAM-C knockout mice with AP. This study demonstrates that during AP, neutrophils that are recruited to the pancreas may migrate back into the circulation and then contribute to ALI. JAM-C downregulation may contribute to AP-associated ALI via promoting neutrophil rTEM.

  17. Propensity of crocin to offset Vipera russelli venom induced oxidative stress mediated neutrophil apoptosis: a biochemical insight.

    Science.gov (United States)

    Santhosh, M Sebastin; Sundaram, M Shanmuga; Sunitha, K; Jnaneshwari, S; Devaraja, S; Kemparaju, K; Girish, K S

    2016-01-01

    Viper envenomation results in inflammation at the bitten site as well as target organs. Neutrophils and other polymorphonuclear leukocytes execute inflammation resolving mechanism and will undergo apoptosis after completing the task. However, the target specific toxins induce neutrophil apoptosis at the bitten site and in circulation prior to their function, thus reducing their number. Circulating activated neutrophils are major source of inflammatory cytokines and leakage of reactive oxygen species (ROS)/other toxic intermediates resulting in aggravation of inflammatory response at the bitten/target site. Therefore, neutralization of venom induced neutrophil apoptosis reduces inflammation besides increasing the functional neutrophil population. Therefore, the present study investigates the venom induced perturbances in isolated human neutrophils and its neutralization by crocin (Crocus sativus) a potent antioxidant carotenoid. Human neutrophils on treatment with venom resulted in altered ROS generation, intracellular Ca(2+) mobilization, mitochondrial membrane depolarization, cyt-c translocation, caspase activation, phosphatidylserine externalization and DNA damage. On the other hand significant protection against oxidative stress and apoptosis were evidenced in crocin pre-treated groups. In conclusion the viper venom induces neutrophil apoptosis and results in aggravation of inflammation and tissue damage. The present study demands the necessity of an auxiliary therapy in addition to antivenin therapy to treat secondary/overlooked complications of envenomation.

  18. [THE NEW APPROACH TO EVALUATION OF ENDOTHELIUM DYSFUNCTION: DETECTION OF NUMBER OF CIRCULATING ENDOTHELIUM CELLS USING FLOW CYTOMETRY TECHNIQUE].

    Science.gov (United States)

    Feoktistova, V S; Vavilkova, T V; Sirotkina, O V; Boldueva, S A; Gaikovaia, L B; Leonova, I A; Laskovets, A B; Ermakov, A I

    2015-04-01

    The endothelium dysfunction takes leading place in pathogenesis of development of cardiovascular diseases. The circulating endothelium cells of peripheral blood can act as a direct cell marker of damage and remodeling of endothelium. The study was carried out to develop a new approach to diagnose of endothelium dysfunction by force of determination of number of circulating endothelium cells using flow cytometry technique and to apply determination of circulating endothelium cells for evaluation of risk of development of ischemic heart disease in women of young and middle age. The study embraced 62 female patients with angiography confirmed ischemic heart disease, exertional angina pectoris at the level of functional class I-II (mean age 51 ± 6 years) and 49 women without anamnesis of ischemic heart disease (mean age 52 ± 9 years). The occurrence of more than three circulating endothelium cells by 3 x 105 leukocytes in peripheral blood increases relative risk of development of ischemic heart disease up to 4 times in women of young and middle age and risk of development of acute myocardial infarction up to 8 times in women with ischemic heart disease. The study demonstrated possibility to apply flow cytometry technique to quantitatively specify circulating endothelium cells in peripheral blood and forecast risk of development of ischemic heart disease in women of young and middle age depending on level of circulating endothelium cells.

  19. Reduction of body temperature governs neutrophil retention in hibernating and nonhibernating animals by margination

    NARCIS (Netherlands)

    Bouma, Hjalmar R.; Dugbartey, George J.; Boerema, Ate S.; Talaei, Fatemeh; Herwig, Annika; Goris, Maaike; van Buiten, Azuwerus; Strijkstra, Arjen M.; Carey, Hannah V.; Henning, Robert H.; Kroese, Frans G. M.

    2013-01-01

    Low body temperature leads to decrease of circulating neutrophils due to margination in hibernating and nonhibernating animals. Hibernation consists of periods of low metabolism, called torpor, interspersed by euthermic arousal periods. During deep and daily (shallow) torpor, the number of circulati

  20. Neutrophil biology

    OpenAIRE

    Kobayashi, Yoshiro

    2015-01-01

    Neutrophil extracellular traps (NETs) are involved in bacterial killing as well as autoimmunity, because NETs contain proteases, bactericidal peptides, DNA and ribonucleoprotein. NETs are formed via a novel type of cell death called NETosis. NETosis is distinct from apoptosis, but it resembles necrosis in that both membranes are not intact so that they allow intracellular proteins to leak outside of the cells. Removal of NETs and neutrophils undergoing NETosis by phagocytes and its subsequent...

  1. Adiponectin levels are associated with the number and activity of circulating endothelial progenitor cells in patients with coronary artery disease

    Institute of Scientific and Technical Information of China (English)

    Zhi-qiang YING; Dan-dan ZHONG; Geng XU; Miao-yan CHEN; Qing-yu CHEN

    2009-01-01

    Objective: To study the relationship between plasma adiponectin concentration and the functional activities of circulating endothelial progenitor cells (EPCs) in patients with coronary artery disease (CAD). Methods: Circulating EPCs were enumerated as AC133+/KDR+ cells via flow cytometry and identified by co-staining with Dii-acLDL and fluorescein isothiocy-anate (FITC)-conjugated lectin under a fluorescent microscope. The migratory capacity of EPCs was measured by modified Boyden chamber assay. Adhesion capacity was performed to count adherent cells after replating EPCs on six-well culture dishes coated with fibronectin. Results: The number of circulating EPCs (AC133+/KDR+ cells) decreased significantly in CAD patients, compared with control subjects [(74.2±12.3) vs (83.5±12.9) cells/ml blood, P<0.0\\]. In addition, the number of EPCs also decreased in CAD patients after ex vivo cultivation [(54.4±8.6) vs (71.9±11.6) EPCs/field, P<0.01]. Both circulating EPCs and differentiated EPCs were positively correlated with plasma adiponectin concentration. The functional activities of EPCs from CAD patients, such as migratory and adherent capacities, were also impaired, compared with control subjects, and positively correlated with plasma adiponectin concentration. Conclusion: The study demonstrates that the impairment of the number and functional activities of EPCs in CAD patients is correlated with their lower plasma adiponectin concentrations.

  2. SDF1 gene variation is associated with circulating SDF1alpha level and endothelial progenitor cell number: the Bruneck Study.

    Directory of Open Access Journals (Sweden)

    Qingzhong Xiao

    Full Text Available BACKGROUND: Stromal cell-derived factor-1 (SDF1 and its receptor CXC chemokine receptor 4 (CXCR4 play a critical role in progenitor cell homing, mobilization and differentiation. It would be interesting to assess the predictive value of SDF-1alpha level for EPC number, and to ascertain whether there is a relationship between SDF1 gene variation, plasma SDF-1alpha level, and the number and function of circulating EPCs. We also tested whether EPC number and function was related to CXCR4 gene variation. METHODOLOGY AND PRINCIPAL FINDINGS: We genotyped a cohort of individuals who participated in the Bruneck Study for single nucleotide polymorphisms (SNPs in the SDF1 and CXCR4 genes, and measured blood SDF1alpha level as well as EPC number and function. SDF1alpha levels were correlated with age, gender, alcohol consumption, circulating reticulocyte numbers, and concentrations of matrix metalloproteinase-9, C-reactive protein, cystatin C, fibrinogen and homocytein. In blood samples taken in 2005, EPC number was inversely associated with SDF1alpha level (p<0.001. EPC number in 2005 was also inversely associated with SDF1alpha level in 2000 (p = 0.009, suggesting a predictive value of plasma SDF1alpha level for EPC number. There was an association between the SDF1 gene rs2297630 SNP A/A genotype, increased SDF1alpha level (p = 0.002 and lower EPC number (p = 0.006. CONCLUSIONS: Our data indicate that a SDF1 gene variation (rs2297630 has an influence on SDF1alpha level and circulating EPC number, and that plasma SDF1alpha level is a predictor of EPC number.

  3. A short-term extremely low frequency electromagnetic field exposure increases circulating leukocyte numbers and affects HPA-axis signaling in mice.

    Science.gov (United States)

    de Kleijn, Stan; Ferwerda, Gerben; Wiese, Michelle; Trentelman, Jos; Cuppen, Jan; Kozicz, Tamas; de Jager, Linda; Hermans, Peter W M; Verburg-van Kemenade, B M Lidy

    2016-10-01

    There is still uncertainty whether extremely low frequency electromagnetic fields (ELF-EMF) can induce health effects like immunomodulation. Despite evidence obtained in vitro, an unambiguous association has not yet been established in vivo. Here, mice were exposed to ELF-EMF for 1, 4, and 24 h/day in a short-term (1 week) and long-term (15 weeks) set-up to investigate whole body effects on the level of stress regulation and immune response. ELF-EMF signal contained multiple frequencies (20-5000 Hz) and a magnetic flux density of 10 μT. After exposure, blood was analyzed for leukocyte numbers (short-term and long-term) and adrenocorticotropic hormone concentration (short-term only). Furthermore, in the short-term experiment, stress-related parameters, corticotropin-releasing hormone, proopiomelanocortin (POMC) and CYP11A1 gene-expression, respectively, were determined in the hypothalamic paraventricular nucleus, pituitary, and adrenal glands. In the short-term but not long-term experiment, leukocyte counts were significantly higher in the 24 h-exposed group compared with controls, mainly represented by increased neutrophils and CD4 ± lymphocytes. POMC expression and plasma adrenocorticotropic hormone were significantly lower compared with unexposed control mice. In conclusion, short-term ELF-EMF exposure may affect hypothalamic-pituitary-adrenal axis activation in mice. Changes in stress hormone release may explain changes in circulating leukocyte numbers and composition. Bioelectromagnetics. 37:433-443, 2016. © 2016 The Authors. Bioelectromagnetics Published by Wiley Periodicals, Inc.

  4. Low Number of Detectable Circulating Tumor Cells in Non-metastatic Colon Cancer

    DEFF Research Database (Denmark)

    Thorsteinsson, Morten; Söletormos, György; Jess, Per

    2011-01-01

    The aim of the present study was to detect circulating tumor cells (CTCs) in the peripheral blood of patients with non-metastatic colon cancer and to evaluate whether there is a diurnal variation in the CTC counts. Furthermore, the study aimed to examine the correlation between CTCs and TNM stage...

  5. Asymptotic enumeration theorems for the numbers of spanning trees and Eulerian trails in circulant digraphs and graphs

    Institute of Scientific and Technical Information of China (English)

    张福基; 永学荣

    1999-01-01

    The asymptotic properties of the numbers of spanning trees and Eulerian trails in circulant digraphs and graphs are studied. Let C(p, s1, s2,…, sk) be a directed cireulant graph. Let T(C(p, s1, s2, …, sk)) and E(C(p, s1, s2, …, sk)) be the numbers of spanning trees and of Eulerian trails, respectively. Then lim (1/k)(T(C(p, s1, S2, …, sk))1/p)=1, p→∞ lim (1/k!)(E(C(p, s1, s2, …, sk))1/p)=1,Furthermore, their line digraph and iterations are dealt with and similar results are obtained for undirected circulant graphs.

  6. Dynamic Changes in Numbers and Properties of Circulating Tumor Cells and Their Potential Applications

    Energy Technology Data Exchange (ETDEWEB)

    Tseng, Ju-Yu [Institute of Microbiology and Immunology, School of Life Science, National Yang-Ming University, Taipei 11221, Taiwan (China); Yang, Chih-Yung [Department of Education and Research, Taipei City Hospital, Taipei 10629, Taiwan (China); Liang, Shu-Ching [Institute of Microbiology and Immunology, School of Life Science, National Yang-Ming University, Taipei 11221, Taiwan (China); Liu, Ren-Shyan [Molecular and Genetic Imaging Core/Taiwan Mouse Clinic, Taipei 11529, Taiwan (China); Biomedical Imaging Research Center, Institute of Clinical Medicine, School of Medicine, National Yang-Ming University, Taipei 11221, Taiwan (China); National PET/Cyclotron Center, Taipei Veterans General Hospital, Taipei, 11217, Taiwan (China); Jiang, Jeng-Kai, E-mail: jkjiang@vghtpe.gov.tw [Division of Colon & Rectal Surgery, Department of Surgery, Taipei Veterans General Hospital, Taipei 11217, Taiwan (China); Lin, Chi-Hung, E-mail: jkjiang@vghtpe.gov.tw [Institute of Microbiology and Immunology, School of Life Science, National Yang-Ming University, Taipei 11221, Taiwan (China); VGH Yang-Ming Genome Research Center, Taipei 11221, Taiwan (China)

    2014-12-16

    Circulating tumor cells (CTCs) can be detected in the blood of different types of early or advanced cancer using immunology-based assays or nucleic acid methods. The detection and quantification of CTCs has significant clinical utility in the prognosis of metastatic breast, prostate, and colorectal cancers. CTCs are a heterogeneous population of cells and often different from those of their respective primary tumor. Understanding the biology of CTCs may provide useful predictive information for the selection of the most appropriate treatment. Therefore, CTC detection and characterization could become a valuable tool to refine prognosis and serve as a “real-time biopsy” and has the potential to guide precision cancer therapies, monitor cancer treatment, and investigate the process of metastasis.

  7. Heterogeneity of the Mac-1 expression on peripheral blood neutrophils in patients with different types of epithelial ovarian cancer.

    Science.gov (United States)

    Bednarska, Katarzyna; Klink, Magdalena; Wilczyński, Jacek R; Szyłło, Krzysztof; Malinowski, Andrzej; Sułowska, Zofia; Nowak, Marek

    2016-02-01

    The expression level of Mac-1 on the surface of neutrophils is an important indicator of neutrophil activation. Under pathological conditions, Mac-1 is believed a key adhesion molecule that facilitates cancer progression and mediates the adhesion of tumour cells to the endothelium of blood vessels. Our previous findings indicated that circulating peripheral blood neutrophils in patients with advanced epithelial ovarian cancer (EOC) expressed enhanced levels of Mac-1, which was functionally associated with an increased adhesive function of neutrophils. The objective of the current study was to analyse whether the value of individual components of the differential white cell count, including the neutrophil and lymphocyte ratios, which are markers of blood neutrophil activation, might be associated with certain types of ovarian cancer. We showed the increase in Mac-1 expression along with a parallel decrease of L-selectin and PSGL-1 on peripheral blood neutrophils of patients with EOC of early and advanced FIGO stages, which indicates an activated state of neutrophils in comparison to neutrophils of individuals without cancer. Despite a significant difference between Mac-1 expression in patients with and without cancer, a dramatic increase in Mac-1 expression was observed in the blood of patients with undifferentiated carcinomas compared with patients with other histological types of EOC. Moreover, the expression level of Mac-1 correlated with the number of neutrophils in patients with serous, endometrioid and undifferentiated EOC. The results of an ROC analysis demonstrated that the patients with the undifferentiated type of EOC form a distinct group with regard to Mac-1 expression on blood neutrophils. The results suggested a diverse biological cadre of immune cells in patients with undifferentiated ovarian carcinomas compared with patients with other histological types of EOC.

  8. A chemotactic gradient sequestered on endothelial heparan sulfate induces directional intraluminal crawling of neutrophils.

    Science.gov (United States)

    Massena, Sara; Christoffersson, Gustaf; Hjertström, Elina; Zcharia, Eyal; Vlodavsky, Israel; Ausmees, Nora; Rolny, Charlotte; Li, Jin-Ping; Phillipson, Mia

    2010-09-16

    During infection, chemokines sequestered on endothelium induce recruitment of circulating leukocytes into the tissue where they chemotax along chemokine gradients toward the afflicted site. The aim of this in vivo study was to determine whether a chemokine gradient was formed intravascularly and influenced intraluminal neutrophil crawling and transmigration. A chemokine gradient was induced by placing a macrophage inflammatory protein-2 (MIP-2)-containing (CXCL2) gel on the cremaster muscle of anesthetized wild-type mice or heparanase-overexpressing transgenic mice (hpa-tg) with truncated heparan sulfate (HS) side chains. Neutrophil-endothelial interactions were visualized by intravital microscopy and chemokine gradients detected by confocal microscopy. Localized extravascular chemokine release (MIP-2 gel) induced directed neutrophil crawling along a chemotactic gradient immobilized on the endothelium and accelerated their recruitment into the target tissue compared with homogeneous extravascular chemokine concentration (MIP-2 superfusion). Endothelial chemokine sequestration occurred exclusively in venules and was HS-dependent, and neutrophils in hpa-tg mice exhibited random crawling. Despite similar numbers of adherent neutrophils in hpa-tg and wild-type mice, the altered crawling in hpa-tg mice was translated into decreased number of emigrated neutrophils and ultimately decreased the ability to clear bacterial infections. In conclusion, an intravascular chemokine gradient sequestered by endothelial HS effectively directs crawling leukocytes toward transmigration loci close to the infection site.

  9. Circulating histamine and neutrophil chemotactic activity during allergen-induced asthma: the effect of inhaled antihistamines and anti-allergic compounds.

    Science.gov (United States)

    Morgan, D J; Moodley, I; Cundell, D R; Sheinman, B D; Smart, W; Davies, R J

    1985-07-01

    Plasma histamine and serum neutrophil chemotactic activity (S-NCA) were measured in ten atopic asthmatic patients on four separate occasions after allergen bronchial provocation testing (BPT). Single doses of inhaled sodium cromoglycate (SCG; 20 mg), clemastine (0.5 mg), ketotifen (0.5 mg) and isotonic saline (0.9% NaCl) placebo were administered 30 min before bronchial provocation testing in random order and double-blind. The airflow obstruction after BPT was monitored by measurement of forced expiratory volume in 1 s (FEV1). Plasma histamine was measured by the double-isotope radioenzymatic assay and S-NCA by a modified Boyden chamber technique. A highly significant decrease in FEV1 after BPT occurred on the placebo pre-treatment visit (P less than 0.001). Prior administration of inhaled SCG, clemastine and ketotifen significantly reduced the decrease in airflow obstruction seen after BPT when compared with placebo treatment (P less than 0.01, P less than 0.02, P less than 0.05 respectively). No significant alteration in plasma histamine was detected during allergen-induced airflow obstruction. Levels of S-NCA were significantly higher 5, 10 and 15 min after BPT when compared with the pre-challenge level (P less than 0.01, P less than 0.01, P less than 0.001 respectively). These levels were not significantly decreased when airflow obstruction was inhibited by the prior inhalation of SCG, clemastine or ketotifen.

  10. Circulating levels of matrix metalloproteinase-9 (MMP-9, neutrophil gelatinase-associated lipocalin (NGAL and their complex MMP-9/NGAL in breast cancer disease

    Directory of Open Access Journals (Sweden)

    Nonni Afroditi

    2009-11-01

    Full Text Available Abstract Background Recent evidence suggests that neutrophil gelatinase-associated lipocalin (NGAL expression is induced in many types of human cancer, while detection of its complex with matrix metalloproteinase-9 (MMP-9 is correlated with cancer disease status. We aim to evaluate the serum expression of MMP-9, NGAL and their complex (MMP-9/NGAL during the diagnostic work-up of women with breast abnormalities and investigate their correlation with disease severity. Methods The study included 113 women with non-palpable breast lesions undergoing vacuum-assisted breast biopsy for histological diagnosis, and 30 healthy women, which served as controls. Expression levels of MMP-9, NGAL and their complex MMP-9/NGAL were determined in peripheral blood samples with immunoenzymatic assays. Results Women with invasive ductal carcinoma exhibited significantly increased levels of MMP-9, NGAL and MMP-9/NGAL compared to healthy controls (MMP-9: p Conclusion These findings suggest that the serum measurement of MMP-9 and NGAL may be useful in non-invasively monitoring breast cancer progression, while supporting their potential role as early biomarkers of breast disease status.

  11. Neutrophil Functions in Periodontal Homeostasis

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    Ricarda Cortés-Vieyra

    2016-01-01

    Full Text Available Oral tissues are constantly exposed to damage from the mechanical effort of eating and to microorganisms, mostly bacteria. In healthy gingiva tissue remodeling and a balance between bacteria and innate immune cells are maintained. However, excess of bacteria biofilm (plaque creates an inflammation state that recruits more immune cells, mainly neutrophils to the gingiva. Neutrophils create a barrier for bacteria to reach inside tissues. When neutrophils are insufficient, bacteria thrive causing more inflammation that has been associated with systemic effects on other conditions such as atherosclerosis, diabetes, and cancer. But paradoxically when neutrophils persist, they can also promote a chronic inflammatory state that leads to periodontitis, a condition that leads to damage of the bone-supporting tissues. In periodontitis, bone loss is a serious complication. How a neutrophil balance is needed for maintaining healthy oral tissues is the focus of this review. We present recent evidence on how alterations in neutrophil number and function can lead to inflammatory bone loss, and how some oral bacteria signal neutrophils to block their antimicrobial functions and promote an inflammatory state. Also, based on this new information, novel therapeutic approaches are discussed.

  12. Effects of endogenous and exogenous catecholamines on LPS-induced neutrophil trafficking and activation.

    Science.gov (United States)

    Abraham, E; Kaneko, D J; Shenkar, R

    1999-01-01

    Endotoxemia produces elevations in catecholamine levels in the pulmonary and systemic circulation as well as rapid increases in neutrophil number and proinflammatory cytokine expression in the lungs. In the present experiments, we examined the effects of endogenous and exogenous adrenergic stimulation on endotoxin-induced lung neutrophil accumulation and activation. Levels of interleukin (IL)-1beta, tumor necrosis factor (TNF)-alpha, and macrophage inflammatory protein (MIP)-2 mRNAs were increased in lung neutrophils from endotoxemic mice compared with those present in lung neutrophils from control mice or in peripheral blood neutrophils from endotoxemic or control mice. Treatment with the beta-adrenergic antagonist propranolol before endotoxin administration did not affect trafficking of neutrophils to the lungs or the expression of IL-1beta, TNF-alpha, or MIP-2 by lung neutrophils. Administration of the alpha-adrenergic antagonist phentolamine before endotoxemia did not alter lung neutrophil accumulation as measured by myeloperoxidase (MPO) levels but did result in significant increases in IL-1beta, TNF-alpha, and MIP-2 mRNA expression by lung neutrophils compared with endotoxemia alone. Administration of the alpha1-adrenergic agonist phenylephrine before endotoxin did not affect trafficking of neutrophils to the lungs but was associated with significantly increased expression of TNF-alpha and MIP-2 mRNAs by lung neutrophils compared with that found after endotoxin alone. In contrast, treatment with the alpha2-adrenergic agonist UK-14304 prevented endotoxin-induced increases in lung MPO and lung neutrophil cytokine mRNA levels. The suppressive effects of UK-14304 on endotoxin-induced increases in lung MPO were not affected by administration of the nitric oxide synthase inhibitor N-nitro-L-arginine methyl ester. These data demonstrate that the initial accumulation and activation of neutrophils in the lungs after endotoxemia can be significantly diminished by alpha

  13. Neutrophils recruited to sites of infection protect from virus challenge by releasing neutrophil extracellular traps.

    Science.gov (United States)

    Jenne, Craig N; Wong, Connie H Y; Zemp, Franz J; McDonald, Braedon; Rahman, Masmudur M; Forsyth, Peter A; McFadden, Grant; Kubes, Paul

    2013-02-13

    Neutrophils mediate bacterial clearance through various mechanisms, including the release of mesh-like DNA structures or neutrophil extracellular traps (NETs) that capture bacteria. Although neutrophils are also recruited to sites of viral infection, their role in antiviral innate immunity is less clear. We show that systemic administration of virus analogs or poxvirus infection induces neutrophil recruitment to the liver microvasculature and the release of NETs that protect host cells from virus infection. After systemic intravenous poxvirus challenge, mice exhibit thrombocytopenia and the recruitment of both neutrophils and platelets to the liver vasculature. Circulating platelets interact with, roll along, and adhere to the surface of adherent neutrophils, forming large, dynamic aggregates. These interactions facilitate the release of NETs within the liver vasculature that are able to protect host cells from poxvirus infection. These findings highlight the role of NETs and early tissue-wide responses in preventing viral infection.

  14. [A Large Number of Circulating Tumor Cells(CTCs)Can Be Isolated from Samples Obtained by Using Leukapheresis Procedures].

    Science.gov (United States)

    Soya, Ryoko; Taguchi, Jyunichi; Nagakawa, Yuichi; Takahashi, Osamu; Sandoh, Norimasa; Hosokawa, Yuichi; Kasuya, Kazuhiko; Umeda, Naoki; Okamoto, Masato; Tsujitani, Shunichi; Tsuchida, Akihiko

    2015-09-01

    We hypothesized that a large number of circulating tumor cells(CTCs)may be isolated from samples obtained by using the leukapheresis procedures that are utilized to collect peripheral blood mononuclear cells for dendritic cell vaccine therapy. We utilized the CellSearch System to determine the number of CTCs in samples obtained by using leukapheresis in 7 patients with colorectal cancer, 5 patients with breast cancer, and 3 patients with gastric cancer. In all patients, a large number of CTCs were isolated. The mean number of CTCs per tumor was 17.1(range 10-34)in colorectal cancer, 10.0(range 2-27)in breast cancer, and 24.0(range 2-42)in gastric cancer. We succeeded in culturing the isolated CTCs from 7 patients with colorectal cancer, 5 patients with breast cancer, and 3 patients with gastric cancer. In conclusion, compared to conventional methods, a large number of CTCs can be obtained by using leukapheresis procedures. The molecular analyses of the CTCs isolated by using this method should be promising in the development of personalized cancer treatments.

  15. Ligation of the adhesion-GPCR EMR2 regulates human neutrophil function.

    Science.gov (United States)

    Yona, Simon; Lin, Hsi-Hsien; Dri, Pietro; Davies, John Q; Hayhoe, Richard P G; Lewis, Sion M; Heinsbroek, Sigrid E M; Brown, K Alun; Perretti, Mauro; Hamann, Jörg; Treacher, David F; Gordon, Siamon; Stacey, Martin

    2008-03-01

    At present, approximately 150 different members of the adhesion-G protein-coupled receptor (GPCR) family have been identified in metazoans. Surprisingly, very little is known about their function, although they all possess large extracellular domains coupled to a seven-transmembrane domain, suggesting a potential role in cell adhesion and signaling. Here, we demonstrate how the human-restricted adhesion-GPCR, EMR2 (epidermal growth factor-like module-containing mucin-like hormone receptor), regulates neutrophil responses by potentiating the effects of a number of proinflammatory mediators and show that the transmembrane region is critical for adhesion-GPCR function. Using an anti-EMR2 antibody, ligation of EMR2 increases neutrophil adhesion and migration, and augments superoxide production and proteolytic enzyme degranulation. On neutrophil activation, EMR2 is rapidly translocated to membrane ruffles and the leading edge of the cell. Further supporting the role in neutrophil activation, EMR2 expression on circulating neutrophils is significantly increased in patients with systemic inflammation. These data illustrate a definitive function for a human adhesion-GPCR within the innate immune system and suggest an important role in potentiating the inflammatory response. Ligation of the adhesion-GPCR EMR2 regulates human neutrophil function.

  16. Prognostic impact of the number of viable circulating cells with high telomerase activity in gastric cancer patients: a prospective study.

    Science.gov (United States)

    Ito, Hiroaki; Inoue, Haruhiro; Kimura, Satoshi; Ohmori, Tohru; Ishikawa, Fumihiro; Gohda, Keigo; Sato, Jun

    2014-07-01

    The identification of circulating tumor cells (CTCs) in peripheral blood is a useful approach to estimate prognosis, monitor disease progression and measure treatment effects in several types of malignancies. We have previously used OBP-401, a telomerase-specific, replication-selective, oncolytic adenoviral agent carrying the green fluorescent protein (GFP) gene. GFP-positive cells (GFP+ cells) were counted under a fluorescence microscope. Our results showed that the number of at least 7.735 µm in diameter GFP+ cells (L-GFP+ cells) in the peripheral blood was a significant marker of prognosis in gastric cancer patients. However, tumor cells undergoing epithelial-mesenchymal transition (EMT) have been reported to be smaller in size than cells without EMT features; thus, CTCs undergoing EMT may escape detection with this technique. Therefore, in this study, we analyzed the relationship between patient outcome and the number of GFP+ cells of any size. We obtained peripheral blood samples from 65 patients with gastric cancer. After infection of OBP-401, GFP+ cells were counted and measured. The relationship between the number of GFP+ cells and surgical outcome was analyzed. The median follow-up period of the surviving patients was 36 months. A significant difference in overall survival was found between patients with 0-5 and patients with ≥6 L-GFP+ cells. No clear relationship was established between the number of small-sized GFP+ cells and patient prognosis. The number of L-GFP+ cells was significantly related to overall survival in patients with gastric cancer. The detection of L-GFP+ cells using OBP-401 may be a useful prognostic marker in gastric cancer.

  17. Labeling of rabbit neutrophils with (/sup 111/In)oxine

    Energy Technology Data Exchange (ETDEWEB)

    Lane, T.A. (Veterans Administration Medical Center, San Diego, CA (USA). Dept. of Pathology); Bergum, P.W.; Lichter, J.P.; Spragg, R.G. (California Univ., San Diego, La Jolla (USA). School of Medicine)

    1982-06-25

    The successful labeling of rabbit peripheral blood neutrophils with (/sup 111/In)oxine is reported here. Standard techniques for preparation of rabbit neutrophils, while acceptable for maintenance of in vitro function, rendered the neutrophils ineffective for in vivo use after labeling with /sup 111/In. Specifically, rabbit neutrophils were sensitive to the use of hypotonic shock for red cell elimination, centrifugation into a button during preparation, and the presence of oxine during chemotaxis in vitro. Using a carefully modified method of neutrophil preparation and labeling, it was found that /sup 111/In-labeled rabbit neutrophils retained normal in vitro function, including chemotaxis. In addition, using this method, 34% +- 5% of labeled neutrophils were recoverable in peripheral blood 5 min after intravenous injection. The half-life of circulating radiolabeled neutrophils was 5.6 +- 2 h. Continuous external imaging of radiolabeled neutrophils after intravenous injection showed initial lung uptake, followed by rapid clearance of radioactivity in the lungs (50% clearance in 10.5 +- 3.3 min.). Hepatic radioactivity was maximal by 30 min after injection and thereafter slowly declined. Finally, it was found that /sup 111/In-labeled rabbit neutrophils migrated to sites of artificially induced inflammation. These findings indicate that /sup 111/In-labeled rabbit neutrophils, if prepared under optimal conditions, should provide a useful tool for investigating the fate of neutrophils in experimental inflammatory conditions in this animal.

  18. Neutrophil Responses to Sterile Implant Materials.

    Directory of Open Access Journals (Sweden)

    Siddharth Jhunjhunwala

    Full Text Available In vivo implantation of sterile materials and devices results in a foreign body immune response leading to fibrosis of implanted material. Neutrophils, one of the first immune cells to be recruited to implantation sites, have been suggested to contribute to the establishment of the inflammatory microenvironment that initiates the fibrotic response. However, the precise numbers and roles of neutrophils in response to implanted devices remains unclear. Using a mouse model of peritoneal microcapsule implantation, we show 30-500 fold increased neutrophil presence in the peritoneal exudates in response to implants. We demonstrate that these neutrophils secrete increased amounts of a variety of inflammatory cytokines and chemokines. Further, we observe that they participate in the foreign body response through the formation of neutrophil extracellular traps (NETs on implant surfaces. Our results provide new insight into neutrophil function during a foreign body response to peritoneal implants which has implications for the development of biologically compatible medical devices.

  19. Achyrocline satureioides (Lam. D.C. Hydroalcoholic Extract Inhibits Neutrophil Functions Related to Innate Host Defense

    Directory of Open Access Journals (Sweden)

    Eric Diego Barioni

    2013-01-01

    Full Text Available Achyrocline satureioides (Lam. D.C. is a herb native to South America, and its inflorescences are popularly employed to treat inflammatory diseases. Here, the effects of the in vivo actions of the hydroalcoholic extract obtained from inflorescences of A. satureioides on neutrophil trafficking into inflamed tissue were investigated. Male Wistar rats were orally treated with A. satureioides extract, and inflammation was induced one hour later by lipopolysaccharide injection into the subcutaneous tissue. The number of leukocytes and the amount of chemotactic mediators were quantified in the inflammatory exudate, and adhesion molecule and toll-like receptor 4 (TLR-4 expressions and phorbol-myristate-acetate- (PMA- stimulated oxidative burst were quantified in circulating neutrophils. Leukocyte-endothelial interactions were quantified in the mesentery tissue. Enzymes and tissue morphology of the liver and kidney were evaluated. Treatment with A. satureioides extract reduced neutrophil influx and secretion of leukotriene B4 and CINC-1 in the exudates, the number of rolling and adhered leukocytes in the mesentery postcapillary venules, neutrophil L-selectin, β2-integrin and TLR-4 expression, and oxidative burst, but did not cause an alteration in the morphology and activities of liver and kidney. Together, the data show that A. satureioides extract inhibits neutrophil functions related to the innate response and does not cause systemic toxicity.

  20. The hydrodynamic and ultrasound-induced forces on microbubbles under high Reynolds number flow representative of the human systemic circulation

    Science.gov (United States)

    Clark, Alicia; Aliseda, Alberto

    2016-11-01

    Ultrasound contrast agents (UCAs) are micron-sized bubbles that are used in conjunction with ultrasound (US) in medical applications such as thrombolysis and targeted intravenous drug delivery. Previous work has shown that the Bjerknes force, due to the phase difference between the incoming US pressure wave and the bubble volume oscillations, can be used to manipulate the trajectories of microbubbles. Our work explores the behavior of microbubbles in medium sized blood vessels under both uniform and pulsatile flows at a range of physiologically relevant Reynolds and Womersley numbers. High speed images were taken of the microbubbles in an in-vitro flow loop that replicates physiological flow conditions. During the imaging, the microbubbles were insonified at different diagnostic ultrasound settings (varying center frequency, PRF, etc.). An in-house Lagrangian particle tracking code was then used to determine the trajectories of the microbubbles and, thus, a dynamic model for the microbubbles including the Bjerknes forces acting on them, as well as drag, lift, and added mass. Preliminary work has also explored the behavior of the microbubbles in a patient-specific model of a carotid artery bifurcation to demonstrate the feasibility of preferential steering of microbubbles towards the intracranial circulation with US.

  1. Hematopoietic overexpression of FOG1 does not affect B-cells but reduces the number of circulating eosinophils.

    Directory of Open Access Journals (Sweden)

    Camille Du Roure

    Full Text Available We have identified expression of the gene encoding the transcriptional coactivator FOG-1 (Friend of GATA-1; Zfpm1, Zinc finger protein multitype 1 in B lymphocytes. We found that FOG-1 expression is directly or indirectly dependent on the B cell-specific coactivator OBF-1 and that it is modulated during B cell development: expression is observed in early but not in late stages of B cell development. To directly test in vivo the role of FOG-1 in B lymphocytes, we developed a novel embryonic stem cell recombination system. For this, we combined homologous recombination with the FLP recombinase activity to rapidly generate embryonic stem cell lines carrying a Cre-inducible transgene at the Rosa26 locus. Using this system, we successfully generated transgenic mice where FOG-1 is conditionally overexpressed in mature B-cells or in the entire hematopoietic system. While overexpression of FOG-1 in B cells did not significantly affect B cell development or function, we found that enforced expression of FOG-1 throughout all hematopoietic lineages led to a reduction in the number of circulating eosinophils, confirming and extending to mammals the known function of FOG-1 in this lineage.

  2. [Ultrastructural changes of neutrophilic granulocytes in dilated cardiomyopathy and their dynamics after blood irradiation with Helium-Neon laser in vitro].

    Science.gov (United States)

    Khomeriki, S G; Morozov, I A

    1998-01-01

    Venous blood from 10 patients with dilated cardiomyopathy was irradiated with a laser in vitro. The control group consisted of 20 healthy donors. The neutrophil granulocytes were separated at gradient centrifugation. Alterations of neutrophils manifested with an increase of specific cytoplasmic granules number, thickening of submembrane actin, cell configuration changes with a relative increase of their surface. Laser irradiation of the blood resulted in destruction of the altered (less resistant) cells while morphometric parameters of the remaining cells approaches those of donor cells. Thus, low-intensity laser irradiation results in the renewal of the neutrophil population in patients with dilated cardiomyopathy and normalization of structural-functional changes in the circulating neutrophil population.

  3. Neutrophils at work

    DEFF Research Database (Denmark)

    Nauseef, William M; Borregaard, Niels

    2014-01-01

    In this Review we discuss data demonstrating recently recognized aspects of neutrophil homeostasis in the steady state, granulopoiesis in 'emergency' conditions and interactions of neutrophils with the adaptive immune system. We explore in vivo observations of the recruitment of neutrophils from ...

  4. Hfe deficiency impairs pulmonary neutrophil recruitment in response to inflammation.

    Directory of Open Access Journals (Sweden)

    Karolina Benesova

    Full Text Available Regulation of iron homeostasis and the inflammatory response are tightly linked to protect the host from infection. Here we investigate how imbalanced systemic iron homeostasis in a murine disease model of hereditary hemochromatosis (Hfe(-/- mice affects the inflammatory responses of the lung. We induced acute pulmonary inflammation in Hfe(-/- and wild-type mice by intratracheal instillation of 20 µg of lipopolysaccharide (LPS and analyzed local and systemic inflammatory responses and iron-related parameters. We show that in Hfe(-/- mice neutrophil recruitment to the bronchoalveolar space is attenuated compared to wild-type mice although circulating neutrophil numbers in the bloodstream were elevated to similar levels in Hfe(-/- and wild-type mice. The underlying molecular mechanisms are likely multifactorial and include elevated systemic iron levels, alveolar macrophage iron deficiency and/or hitherto unexplored functions of Hfe in resident pulmonary cell types. As a consequence, pulmonary cytokine expression is out of balance and neutrophils fail to be recruited efficiently to the bronchoalveolar compartment, a process required to protect the host from infections. In conclusion, our findings suggest a novel role for Hfe and/or imbalanced iron homeostasis in the regulation of the inflammatory response in the lung and hereditary hemochromatosis.

  5. Neutrophils: important contributors to tumor progression and metastasis.

    Science.gov (United States)

    Swierczak, Agnieszka; Mouchemore, Kellie A; Hamilton, John A; Anderson, Robin L

    2015-12-01

    The presence of neutrophils in tumors has traditionally been considered to be indicative of a failed immune response against cancers. However, there is now evidence showing that neutrophils can promote tumor growth, and increasingly, the data support an active role for neutrophils in tumor progression to distant metastasis. Neutrophils have been implicated in promoting metastasis in cancer patients, where neutrophil numbers and neutrophil-related factors and functions have been associated with progressive disease. Nevertheless, the role of neutrophils in tumors, both at the primary and secondary sites, remains controversial, with some studies reporting their anti-tumor functions. This review will focus on the data demonstrating a role for neutrophils in both tumor growth and metastasis and will attempt to clarify the discrepancies in the literature.

  6. NET amyloidogenic backbone in human activated neutrophils.

    Science.gov (United States)

    Pulze, L; Bassani, B; Gini, E; D'Antona, P; Grimaldi, A; Luini, A; Marino, F; Noonan, D M; Tettamanti, G; Valvassori, R; de Eguileor, M

    2016-03-01

    Activated human neutrophils produce a fibrillar DNA network [neutrophil extracellular traps (NETs)] for entrapping and killing bacteria, fungi, protozoa and viruses. Our results suggest that the neutrophil extracellular traps show a resistant amyloidogenic backbone utilized for addressing reputed proteins and DNA against the non-self. The formation of amyloid fibrils in neutrophils is regulated by the imbalance of reactive oxygen species (ROS) in the cytoplasm. The intensity and source of the ROS signal is determinant for promoting stress-associated responses such as amyloidogenesis and closely related events: autophagy, exosome release, activation of the adrenocorticotrophin hormone/α-melanocyte-stimulating hormone (ACTH/α-MSH) loop and synthesis of specific cytokines. These interconnected responses in human activated neutrophils, that have been evaluated from a morphofunctional and quantitative viewpoint, represent primitive, but potent, innate defence mechanisms. In invertebrates, circulating phagocytic immune cells, when activated, show responses similar to those described previously for activated human neutrophils. Invertebrate cells within endoplasmic reticulum cisternae produce a fibrillar material which is then assembled into an amyloidogenic scaffold utilized to convey melanin close to the invader. These findings, in consideration to the critical role played by NET in the development of several pathologies, could explain the structural resistance of these scaffolds and could provide the basis for developing new diagnostic and therapeutic approaches in immunomediated diseases in which the innate branch of the immune system has a pivotal role.

  7. Type 2 diabetes mellitus is associated with an imbalance in circulating endothelial and smooth muscle progenitor cell numbers

    NARCIS (Netherlands)

    van Ark, J.; Moser, J.; Lexis, C. P. H.; Bekkema, F.; Pop, I.; van der Horst, I. C. C.; Zeebregts, C. J.; van Goor, H.; Wolffenbuttel, B. H. R.; Hillebrands, J. L.

    2012-01-01

    Individuals with type 2 diabetes mellitus have increased rates of macrovascular disease (MVD). Endothelial progenitor cells (EPCs), circulating angiogenic cells (CACs) and smooth muscle progenitor cells (SMPCs) are suggested to play a role in the pathogenesis of MVD. The relationship between vasoreg

  8. SDF1 Gene Variation Is Associated with Circulating SDF1 alpha Level and Endothelial Progenitor Cell Number-The Bruneck Study

    OpenAIRE

    Xiao, Q.; Ye, S.; Oberhollenzer, F; Mayr, A; Jahangiri, M; Willeit, J.; Kiechl, S; Xu, Q.

    2008-01-01

    BACKGROUND: Stromal cell-derived factor-1 (SDF1) and its receptor CXC chemokine receptor 4 (CXCR4) play a critical role in progenitor cell homing, mobilization and differentiation. It would be interesting to assess the predictive value of SDF-1alpha level for EPC number, and to ascertain whether there is a relationship between SDF1 gene variation, plasma SDF-1alpha level, and the number and function of circulating EPCs. We also tested whether EPC number and function was related to CXCR4 gene ...

  9. Monoclonal B-cell lymphocytosis (MBL) with normal lymphocyte counts is associated with decreased numbers of normal circulating B-cell subsets.

    Science.gov (United States)

    Hauswirth, Alexander W; Almeida, Julia; Nieto, Wendy G; Teodosio, Cristina; Rodriguez-Caballero, Arancha; Romero, Alfonso; López, Antonio; Fernandez-Navarro, Paulino; Vega, Tomas; Perez-Andres, Martin; Valent, Peter; Jäger, Ulrich; Orfao, Alberto

    2012-07-01

    Monoclonal B-cell lymphocytosis (MBL) with normal lymphocyte counts is associated with decreased numbers of normal circulating B-cell subsets.Little is known about the distribution of normal lymphoid cells and their subsets in the peripheral blood (PB) of subjects with monoclonal B-cell lymphocytosis (MBL). In our study, we compared the absolute number of PB lymphoid cells and their subpopulations in 95 MBL cases with normal lymphocyte counts vs. 617 age-/sex-matched non-MBL healthy subjects (controls), using highly sensitive flow cytometry. MBL cases showed significantly reduced numbers of normal circulating B-cells, at the expense of immature and naive B-cells; in addition, CD4+CD8+ double-positive T-cells and CD8+ T-cells were significantly lower and higher vs. controls, respectively. Moreover, most normal B-cell subsets were significantly decreased in PB at >1% MBL-counts, vs. "low-count" MBL cases, and lower amounts of immature/naive B-cells were detected in biclonal (particularly in cases with coexisting CLL-like- and non-CLL-like B-cell clones) vs. monoclonal MBL subjects. In summary, our results show imbalanced (reduced) absolute numbers of recently produced normal circulating B-cells (e.g., immature and naıve B-cells) in MBL, which becomes more pronounced as the MBL cell count increases.

  10. Neutrophilic dermatoses in children.

    Science.gov (United States)

    Berk, David R; Bayliss, Susan J

    2008-01-01

    The neutrophilic dermatoses are rare disorders, especially in children, and are characterized by neutrophilic infiltrates in the skin and less commonly in extracutaneous tissue. The neutrophilic dermatoses share similar clinical appearances and associated conditions, including inflammatory bowel disease, malignancies, and medications. Overlap forms of disease demonstrating features of multiple neutrophilic dermatoses may be seen. The manuscript attempts to provide an up-to-date review of (i) classical neutrophilic dermatoses, focusing on distinctive features in children and (ii) neutrophilic dermatoses which may largely be pediatric or genodermatosis-associated (Majeed, SAPHO [synovitis, severe acne, sterile palmoplantar pustulosis, hyperostosis, and osteitis] syndrome, PAPA (pyogenic sterile arthritis, pyoderma gangrenosum, and acne), PFAPA (periodic fever with aphthous stomatitis, pharyngitis, and cervical adenopathy), and other periodic fever syndromes, and congenital erosive and vesicular dermatosis healing with reticulated supple scarring).

  11. Sitagliptin, a dipeptidyl peptidase-4 inhibitor, increases the number of circulating CD34⁺CXCR4⁺ cells in patients with type 2 diabetes.

    Science.gov (United States)

    Aso, Yoshimasa; Jojima, T; Iijima, T; Suzuki, K; Terasawa, T; Fukushima, M; Momobayashi, A; Hara, K; Takebayashi, K; Kasai, K; Inukai, T

    2015-12-01

    We investigated the effects of sitagliptin, a dipeptidyl peptidase (DPP)-4 inhibitor, on the number of circulating CD34(+)CXCR4(+)cells, a candidate for endothelial progenitor cells (EPCs), plasma levels of stromal cell-derived factor (SDF)-1α, a ligand for CXCR4 receptor and a substrate for DPP-4, and plasma levels of interferon-inducible protein (IP)-10, for a substrate for DPP-4, in patients with type 2 diabetes. We studied 30 consecutive patients with type 2 diabetes who had poor glycemic control despite treatment with metformin and/or sulfonylurea. Thirty diabetic patients were randomized in a 2:1 ratio into a sitagliptin (50 mg/day) treatment group or an active placebo group (glimepiride 1 mg/day) for 12 weeks. Both groups showed similar improvements in glycemic control. The number of circulating CD34(+)CXCR4(+) cells was increased from 30.5 (20.0, 47.0)/10(6) cells at baseline to 55.5 (31.5, 80.5)/10(6) cells at 12 weeks of treatment with 50 mg/day sitagliptin (P = 0.0014), while showing no significant changes in patients treated with glimepiride. Plasma levels of SDF-1α and IP-10, both physiological substrates of endogenous DPP-4 and chemokines, were significantly decreased at 12 weeks of sitagliptin treatment. In conclusion, treatment with sitagliptin increased the number of circulating CD34(+)CXCR4(+) cells by approximately 2-fold in patients with type 2 diabetes.

  12. Neutrophil Responses to Sterile Implant Materials

    OpenAIRE

    Siddharth Jhunjhunwala; Stephanie Aresta-DaSilva; Katherine Tang; David Alvarez; Webber, Matthew J.; Tang, Benjamin C.; Lavin, Danya M.; Omid Veiseh; Doloff, Joshua C; Suman Bose; Arturo Vegas; Minglin Ma; Gaurav Sahay; Alan Chiu; Andrew Bader

    2015-01-01

    In vivo implantation of sterile materials and devices results in a foreign body immune response leading to fibrosis of implanted material. Neutrophils, one of the first immune cells to be recruited to implantation sites, have been suggested to contribute to the establishment of the inflammatory microenvironment that initiates the fibrotic response. However, the precise numbers and roles of neutrophils in response to implanted devices remains unclear. Using a mouse model of peritoneal microcap...

  13. Enhancements to the FAST-MAC Circulation Control Model and Recent High-Reynolds Number Testing in the National Transonic Facility

    Science.gov (United States)

    Milholen, William E., II; Jones, Gregory S.; Chan, David T.; Goodliff, Scott L.; Anders, Scott G.; Melton, Latunia P.; Carter, Melissa B.; Allan, Brian G.; Capone, Francis J.

    2013-01-01

    A second wind tunnel test of the FAST-MAC circulation control model was recently completed in the National Transonic Facility at the NASA Langley Research Center. The model was equipped with four onboard flow control valves allowing independent control of the circulation control plenums, which were directed over a 15% chord simple-hinged flap. The model was configured for low-speed high-lift testing with flap deflections of 30 and 60 degrees, along with the transonic cruise configuration with zero degree flap deflection. Testing was again conducted over a wide range of Mach numbers up to 0.88, and Reynolds numbers up to 30 million based on the mean chord. The first wind tunnel test had poor transonic force and moment data repeatability at mild cryogenic conditions due to inadequate thermal conditioning of the balance. The second test demonstrated that an improvement to the balance heating system significantly improved the transonic data repeatability, but also indicated further improvements are still needed. The low-speed highlift performance of the model was improved by testing various blowing slot heights, and the circulation control was again demonstrated to be effective in re-attaching the flow over the wing at off-design transonic conditions. A new tailored spanwise blowing technique was also demonstrated to be effective at transonic conditions with the benefit of reduced mass flow requirements.

  14. Myeloperoxidase Stimulates Neutrophil Degranulation.

    Science.gov (United States)

    Grigorieva, D V; Gorudko, I V; Sokolov, A V; Kostevich, V A; Vasilyev, V B; Cherenkevich, S N; Panasenko, O M

    2016-08-01

    Myeloperoxidase, heme enzyme of azurophilic granules in neutrophils, is released into the extracellular space in the inflammation foci. In neutrophils, it stimulates a dose-dependent release of lactoferrin (a protein of specific granules), lysozyme (a protein of specific and azurophilic granules), and elastase (a protein of azurophilic granules). 4-Aminobenzoic acid hydrazide, a potent inhibitor of peroxidase activity of myeloperoxidase, produced no effect on neutrophil degranulation. Using signal transduction inhibitors (genistein, methoxyverapamil, wortmannin, and NiCl2), we demonstrated that myeloperoxidase-induced degranulation of neutrophils resulted from enzyme interaction with the plasma membrane and depends on activation of tyrosine kinases, phosphatidylinositol 3-kinases (PI3K), and calcium signaling. Myeloperoxidase modified by oxidative/halogenation stress (chlorinated and monomeric forms of the enzyme) lost the potency to activate neutrophil degranulation.

  15. Psychological stress promotes neutrophil infiltration in colon tissue through adrenergic signaling in DSS-induced colitis model.

    Science.gov (United States)

    Deng, Que; Chen, Hongyu; Liu, Yanjun; Xiao, Fengjun; Guo, Liang; Liu, Dan; Cheng, Xiang; Zhao, Min; Wang, Xiaomeng; Xie, Shuai; Qi, Siyong; Yin, Zhaoyang; Gao, Jiangping; Chen, Xintian; Wang, Jiangong; Guo, Ning; Ma, Yuanfang; Shi, Ming

    2016-10-01

    Inflammatory bowel disease (IBD) is a chronic intestinal inflammatory condition. Psychological stress has been postulated to affect the clinical symptoms and recurrence of IBD. The exact molecular mechanisms are not fully understood. In the present study, we demonstrate that psychological stress promotes neutrophil infiltration into colon tissues in dextran sulfate sodium (DSS)-induced colitis model. The psychological stress resulted in abnormal expression of the proinflammatory cytokines (IL-1β, IL-6, IL-17A, and IL-22) and neutrophil chemokines (CXCL1 and CXCL2) and overactivation of the STAT3 inflammatory signaling pathway. Under chronic unpredictable stress, the adrenergic nervous system was markedly activated, as the expression of tyrosine hydroxylase, the rate-limiting enzyme in catecholamine biosynthesis, in bone marrow and colonic epithelium was enhanced, especially in the myenteric ganglia. The β-AR agonist isoproterenol mimicked the effects of psychological stress on neutrophilia, neutrophil infiltration, and colonic damage in DSS-induced colitis. The β1-AR/β2-AR inhibitor propranolol reduced the numbers of the neutrophils in the circulation, suppressed neutrophil infiltration into colonic tissues, and attenuated the colonic tissue damage promoted by chronic stress. Propranolol also abolished stress-induced upregulation of proinflammatory cytokines and neutrophil chemokines. Our data reveal a close linkage between the β1-AR/β2-AR activation and neutrophil trafficking and also suggest the critical roles of adrenergic nervous system in exacerbation of inflammation and damage of colonic tissues in experimental colitis. The current study provides a new insight into the mechanisms underlying the association of psychological stress with excessive inflammatory response and pathophysiological consequences in IBD. The findings also suggest a potential application of neuroprotective agents to prevent relapsing immune activation in the treatment of IBD.

  16. Localization and Functionality of the Inflammasome in Neutrophils

    DEFF Research Database (Denmark)

    Bakele, Martina; Joos, Melanie; Burdi, Sofia;

    2014-01-01

    Neutrophils represent the major fraction of circulating immune cells and are rapidly recruited to sites of infection and inflammation. The inflammasome is a multiprotein complex that regulates the generation of IL-1 family proteins. The precise subcellular localization and functionality of the in...... intracellular compartments and release IL-1β and IL-18, but not IL-1α or IL-33 protein. Targeting the neutrophil inflammasome may represent a future therapeutic strategy to modulate neutrophilic inflammatory diseases, such as cystic fibrosis, rheumatoid arthritis, or sepsis....

  17. Neutrophil biology: an update

    OpenAIRE

    Kobayashi, Yoshiro

    2015-01-01

    Neutrophil extracellular traps (NETs) are involved in bacterial killing as well as autoimmunity, because NETs contain proteases, bactericidal peptides, DNA and ribonucleoprotein. NETs are formed via a novel type of cell death called NETosis. NETosis is distinct from apoptosis, but it resembles necrosis in that both membranes are not intact so that they allow intracellular proteins to leak outside of the cells. Removal of NETs and neutrophils undergoing NETosis by phagocytes and its subsequent...

  18. Nanostructured Surfaces to Target and Kill Circulating Tumor Cells While Repelling Leukocytes

    Directory of Open Access Journals (Sweden)

    Michael J. Mitchell

    2012-01-01

    Full Text Available Hematogenous metastasis, the process of cancer cell migration from a primary to distal location via the bloodstream, typically leads to a poor patient prognosis. Selectin proteins hold promise in delivering drug-containing nanocarriers to circulating tumor cells (CTCs in the bloodstream, due to their rapid, force-dependent binding kinetics. However, it is challenging to deliver such nanocarriers while avoiding toxic effects on healthy blood cells, as many possess ligands that adhesively interact with selectins. Herein, we describe a nanostructured surface to capture flowing cancer cells, while preventing human neutrophil adhesion. Microtube surfaces with immobilized halloysite nanotubes (HNTs and E-selectin functionalized liposomal doxorubicin (ES-PEG L-DXR significantly increased the number of breast adenocarcinoma MCF7 cells captured from flow, yet also significantly reduced the number of captured neutrophils. Neutrophils firmly adhered and projected pseudopods on surfaces coated only with liposomes, while neutrophils adherent to HNT-liposome surfaces maintained a round morphology. Perfusion of both MCF7 cells and neutrophils resulted in primarily cancer cell adhesion to the HNT-liposome surface, and induced significant cancer cell death. This work demonstrates that nanostructured surfaces consisting of HNTs and ES-PEG L-DXR can increase CTC recruitment for chemotherapeutic delivery, while also preventing healthy cell adhesion and uptake of therapeutic intended for CTCs.

  19. P-selectin promotes neutrophil extracellular trap formation in mice.

    Science.gov (United States)

    Etulain, Julia; Martinod, Kimberly; Wong, Siu Ling; Cifuni, Stephen M; Schattner, Mirta; Wagner, Denisa D

    2015-07-01

    Neutrophil extracellular traps (NETs) can be released in the vasculature. In addition to trapping microbes, they promote inflammatory and thrombotic diseases. Considering that P-selectin induces prothrombotic and proinflammatory signaling, we studied the role of this selectin in NET formation. NET formation (NETosis) was induced by thrombin-activated platelets rosetting with neutrophils and was inhibited by anti-P-selectin aptamer or anti-P-selectin glycoprotein ligand-1 (PSGL-1) inhibitory antibody but was not induced by platelets from P-selectin(-/-) mice. Moreover, NETosis was also promoted by P-selectin-immunoglobulin fusion protein but not by control immunoglobulin. We isolated neutrophils from mice engineered to overproduce soluble P-selectin (P-selectin(ΔCT/ΔCT) mice). Although the levels of circulating DNA and nucleosomes (indicative of spontaneous NETosis) were normal in these mice, basal neutrophil histone citrullination and presence of P-selectin on circulating neutrophils were elevated. NET formation after stimulation with platelet activating factor, ionomycin, or phorbol 12-myristate 13-acetate was significantly enhanced, indicating that the P-selectin(ΔCT/ΔCT) neutrophils were primed for NETosis. In summary, P-selectin, cellular or soluble, through binding to PSGL-1, promotes NETosis, suggesting that this pathway is a potential therapeutic target for NET-related diseases.

  20. Fatty acids as modulators of neutrophil recruitment, function and survival.

    Science.gov (United States)

    Rodrigues, Hosana G; Takeo Sato, Fabio; Curi, Rui; Vinolo, Marco A R

    2016-08-15

    Neutrophils are well-known to act in the destruction of invading microorganisms. They have also been implicated in the activation of other immune cells including B- and T-lymphocytes and in the resolution of inflammation and tissue regeneration. Neutrophils are produced in the bone marrow and released into the circulation from where they migrate to tissues to perform their effector functions. Neutrophils are in constant contact with fatty acids that can modulate their function, activation and fate (survival or cell death) through different mechanisms. In this review, the effects of fatty acids pertaining to five classes, namely, long-chain saturated fatty acids (LCSFAs), short-chain fatty acids (SCFAs), and omega-3 (n-3), omega-6 (n-6) and omega-9 (n-9) unsaturated fatty acids, on neutrophils and the relevance of these effects for disease development are discussed.

  1. The Role of Neutrophil Collagenase in Endotoxic Acute Lung Injury

    Institute of Scientific and Technical Information of China (English)

    徐涛; 曾邦雄; 李兴旺

    2004-01-01

    The aim of this study was to determine the role of neutrophil collagenase in the pathogenesis of acute lung injury induced by endotoxin. 28 Sprague-Dawley were randomized into control group and LPS-enduced groups. Samples of left lung were obtained in 2 h (group L1 ), 6 h (group L2), 12 h (group L3 ) after intravenous LPS. Immunohistochemsitry was employed for detection of expression of neutrophil collagenase. Pathological scores, lung wet/dry weight ratio and the number of neutrophils were measured. The results showed that the concentration of neutrophil collagenase in LPS-enduced groups (group L1, L2, L3 ) were significantly higher than that of control group (P<0.01). Pathological scores, lung wet/dry weight ratio and the number of neutrophils in LPS-enduced groups (group L1, L2, L3 ) were also significantly higher than that of control group (P<0.01).Moreover, among group L1, L2 and L3, there were significant correlations in concentration of neutrophil collagenase and pathological scores, lung wet/dry weight ratio, the number of neutrophils (P<0.05). The present study showed that neutrophil collagenase play an important role in the pathogenesis and progress of endotoxic acute lung injury.

  2. ADAM9 Is a Novel Product of Polymorphonuclear Neutrophils

    DEFF Research Database (Denmark)

    Roychaudhuri, Robin; Hergrueter, Anja H; Polverino, Francesca

    2014-01-01

    A disintegrin and a metalloproteinase domain (ADAM) 9 is known to be expressed by monocytes and macrophages. In this study, we report that ADAM9 is also a product of human and murine polymorphonuclear neutrophils (PMNs). ADAM9 is not synthesized de novo by circulating PMNs. Rather, ADAM9 protein ...

  3. Major neutrophil functions subverted by Porphyromonas gingivalis

    Directory of Open Access Journals (Sweden)

    Ingar Olsen

    2016-03-01

    Full Text Available Polymorphonuclear leukocytes (neutrophils constitute an integrated component of the innate host defense in the gingival sulcus/periodontal pocket. However, the keystone periodontal pathogen Porphyromonas gingivalis has in the course of evolution developed a number of capacities to subvert this defense to its own advantage. The present review describes the major mechanisms that P. gingivalis uses to subvert neutrophil homeostasis, such as impaired recruitment and chemotaxis, resistance to granule-derived antimicrobial agents and to the oxidative burst, inhibition of phagocytic killing while promoting a nutritionally favorable inflammatory response, and delay of neutrophil apoptosis. Studies in animal models have shown that at least some of these mechanisms promote the dysbiotic transformation of the periodontal polymicrobial community, thereby leading to inflammation and bone loss. It is apparent that neutrophil–P. gingivalis interactions and subversion of innate immunity are key contributing factors to the pathogenesis of periodontal disease.

  4. Circulating progenitor cells in hypertensive subjects: Effectiveness of a treatment with olmesartan in improving cell number and miR profile in addition to expected pharmacological effects

    Science.gov (United States)

    Aragona, Caterina Oriana; Cairo, Valentina; Scuruchi, Michele; Lo Gullo, Alberto; D’Ascola, Angela; Alibrandi, Angela; Loddo, Saverio; Quartuccio, Sebastiano; Morace, Carmela; Mormina, Enricomaria; Basile, Giorgio; Saitta, Antonino; Imbalzano, Egidio

    2017-01-01

    CD34+ circulating progenitor cells (CD34+CPCs) are a population of multipotent cells which can delay the development of atherosclerosis and cardiovascular disease (CVD) in conditions of increased CV risk. MicroRNAs (miRs) 221 and 222 modulate different genes regulating angiogenesis and inflammation; moreover, miR221/22 have beenshown to participate in differentiation and proliferation of CD34+CPCs, inhibiting cell migration and homing. miR221/222 in CD34+CPCs from hypertensive subjects are also increased and associated with CD34+cell number and reactive oxygen species (ROS). We evaluated CD34+CPC number, intracellular miR221/222 and ROS levels, arterial stiffness (AS)and echocardiography indices at baseline (T0).Then, after a six-month treatment with olmesartan, 20 mg/day (T1), in 57 hypertensive patients with left ventricular hypertrophy (LVH) and with no additional risk factor for CVD, and in 29 healthy controls (baseline),fibrinogen, C-reactive protein (CRP), glucose and lipid profiles were also evaluated.At T1, blood pressure values, CRP and fibrinogen levels, ROS and miR221/222 were significantly decreased (all p <0.001), as were AS indices and LV mass index (p<0.001), while cell number was increased (p<0.001). Olmesartan is effective in reducing miR and ROS levels in CD34+CPCs from hypertensive subjects, as well as in increasing CD34+CPC number, providing multilevel CV protection, in addition to its expected pharmacological effects. PMID:28301500

  5. Increase in number of circulating disseminated epithelial cells after surgery for non-small cell lung cancer monitored by MAINTRAC® is a predictor for relapse: A preliminary report

    Directory of Open Access Journals (Sweden)

    Höffken Klaus

    2005-03-01

    Full Text Available Abstract Background Lung cancer still remains one of the most commonly occurring solid tumors and even in stage Ia, surgery fails in 30% of patients who develop distant metastases. It is hypothesized that these must have developed from occult circulating tumor cells present at the time of surgery, or before. The aim of the present study was to detect such cells in the peripheral blood and to monitor these cells following surgery. Methods 30 patients treated for lung cancer with surgery were monitored for circulating epithelial cells (CEC by taking peripheral blood samples before, 2 weeks and 5 months after surgery and/or radiotherapy (RT chemotherapy (CT or combined RT/CT using magnetic bead enrichment and laser scanning cytometry (MAINTRAC® for quantification of these cells. Results In 86% of the patients CEC were detected before surgery and in 100% at 2 weeks and 5 months after surgery. In the control group, which consisted of 100 normal donors without cancer, 97 % were negative for CEC. A significantly higher number of CEC was found preoperatively in patients with squamous cell carcinoma than in those with adenocarcinoma. In correlation to the extent of parenchymal manipulation 2 weeks after surgery, an increase in numbers of CEC was observed with limited resections (18/21 whereas pneumonectomy led to a decrease (5/8 of CEC, 2 weeks after surgery. The third analysis done 5 months after surgery identified 3 groups of patients. In the group of 5 patients who received neo- or adjuvant chemo/radiotherapy there was evidence that monitoring of CEC can evaluate the effects of therapy. Another group of 7 patients who underwent surgery only showed a decrease of CEC and no signs of relapse. A third group of 11 patients who had surgery only, showed an increase of CEC (4 with an initial decrease after surgery and 7 with continuous increase. In the group with a continuous increase during the following 24 months, 2 early relapses in patients with stage Ia

  6. Characterization of Neutrophil Function in Human Cutaneous Leishmaniasis Caused by Leishmania braziliensis

    Science.gov (United States)

    Conceição, Jacilara; Davis, Richard; Carneiro, Pedro Paulo; Giudice, Angela; Muniz, Aline C.; Wilson, Mary E.; Carvalho, Edgar M.; Bacellar, Olívia

    2016-01-01

    Infection with different Leishmania spp. protozoa can lead to a variety of clinical syndromes associated in many cases with inflammatory responses in the skin. Although macrophages harbor the majority of parasites throughout chronic infection, neutrophils are the first inflammatory cells to migrate to the site of infection. Whether neutrophils promote parasite clearance or exacerbate disease in murine models varies depending on the susceptible or resistant status of the host. Based on the hypothesis that neutrophils contribute to a systemic inflammatory state in humans with symptomatic L. braziliensis infection, we evaluated the phenotype of neutrophils from patients with cutaneous leishmaniasis (CL) during the course of L. braziliensis infection. After in vitro infection with L. braziliensis, CL patient neutrophils produced more reactive oxygen species (ROS) and higher levels of CXCL8 and CXCL9, chemokines associated with recruitment of neutrophils and Th1-type cells, than neutrophils from control healthy subjects (HS). Despite this, CL patient and HS neutrophils were equally capable of phagocytosis of L. braziliensis. There was no difference between the degree of activation of neutrophils from CL versus healthy subjects, assessed by CD66b and CD62L expression using flow cytometry. Of interest, these studies revealed that both parasite-infected and bystander neutrophils became activated during incubation with L. braziliensis. The enhanced ROS and chemokine production in neutrophils from CL patients reverted to baseline after treatment of disease. These data suggest that the circulating neutrophils during CL are not necessarily more microbicidal, but they have a more pro-inflammatory profile after parasite restimulation than neutrophils from healthy subjects. PMID:27167379

  7. Characterization of Neutrophil Function in Human Cutaneous Leishmaniasis Caused by Leishmania braziliensis.

    Directory of Open Access Journals (Sweden)

    Jacilara Conceição

    2016-05-01

    Full Text Available Infection with different Leishmania spp. protozoa can lead to a variety of clinical syndromes associated in many cases with inflammatory responses in the skin. Although macrophages harbor the majority of parasites throughout chronic infection, neutrophils are the first inflammatory cells to migrate to the site of infection. Whether neutrophils promote parasite clearance or exacerbate disease in murine models varies depending on the susceptible or resistant status of the host. Based on the hypothesis that neutrophils contribute to a systemic inflammatory state in humans with symptomatic L. braziliensis infection, we evaluated the phenotype of neutrophils from patients with cutaneous leishmaniasis (CL during the course of L. braziliensis infection. After in vitro infection with L. braziliensis, CL patient neutrophils produced more reactive oxygen species (ROS and higher levels of CXCL8 and CXCL9, chemokines associated with recruitment of neutrophils and Th1-type cells, than neutrophils from control healthy subjects (HS. Despite this, CL patient and HS neutrophils were equally capable of phagocytosis of L. braziliensis. There was no difference between the degree of activation of neutrophils from CL versus healthy subjects, assessed by CD66b and CD62L expression using flow cytometry. Of interest, these studies revealed that both parasite-infected and bystander neutrophils became activated during incubation with L. braziliensis. The enhanced ROS and chemokine production in neutrophils from CL patients reverted to baseline after treatment of disease. These data suggest that the circulating neutrophils during CL are not necessarily more microbicidal, but they have a more pro-inflammatory profile after parasite restimulation than neutrophils from healthy subjects.

  8. Sulforaphane restores cellular glutathione levels and reduces chronic periodontitis neutrophil hyperactivity in vitro.

    Directory of Open Access Journals (Sweden)

    Irundika H K Dias

    Full Text Available The production of high levels of reactive oxygen species by neutrophils is associated with the local and systemic destructive phenotype found in the chronic inflammatory disease periodontitis. In the present study, we investigated the ability of sulforaphane (SFN to restore cellular glutathione levels and reduce the hyperactivity of circulating neutrophils associated with chronic periodontitis. Using differentiated HL60 cells as a neutrophil model, here we show that generation of extracellular O2 (. - by the nicotinamide adenine dinucleotide (NADPH oxidase complex is increased by intracellular glutathione depletion. This may be attributed to the upregulation of thiol regulated acid sphingomyelinase driven lipid raft formation. Intracellular glutathione was also lower in primary neutrophils from periodontitis patients and, consistent with our previous findings, patients neutrophils were hyper-reactive to stimuli. The activity of nuclear factor erythroid-2-related factor 2 (Nrf2, a master regulator of the antioxidant response, is impaired in circulating neutrophils from chronic periodontitis patients. Although patients' neutrophils exhibit a low reduced glutathione (GSH/oxidised glutathione (GSSG ratio and a higher total Nrf2 level, the DNA-binding activity of nuclear Nrf2 remained unchanged relative to healthy controls and had reduced expression of glutamate cysteine ligase catalytic (GCLC, and modifier (GCLM subunit mRNAs, compared to periodontally healthy subjects neutrophils. Pre-treatment with SFN increased expression of GCLC and GCM, improved intracellular GSH/GSSG ratios and reduced agonist-activated extracellular O2 (. - production in both dHL60 and primary neutrophils from patients with periodontitis and controls. These findings suggest that a deficiency in Nrf2-dependent pathways may underpin susceptibility to hyper-reactivity in circulating primary neutrophils during chronic periodontitis.

  9. Sulforaphane restores cellular glutathione levels and reduces chronic periodontitis neutrophil hyperactivity in vitro.

    Science.gov (United States)

    Dias, Irundika H K; Chapple, Ian L C; Milward, Mike; Grant, Melissa M; Hill, Eric; Brown, James; Griffiths, Helen R

    2013-01-01

    The production of high levels of reactive oxygen species by neutrophils is associated with the local and systemic destructive phenotype found in the chronic inflammatory disease periodontitis. In the present study, we investigated the ability of sulforaphane (SFN) to restore cellular glutathione levels and reduce the hyperactivity of circulating neutrophils associated with chronic periodontitis. Using differentiated HL60 cells as a neutrophil model, here we show that generation of extracellular O2 (. -) by the nicotinamide adenine dinucleotide (NADPH) oxidase complex is increased by intracellular glutathione depletion. This may be attributed to the upregulation of thiol regulated acid sphingomyelinase driven lipid raft formation. Intracellular glutathione was also lower in primary neutrophils from periodontitis patients and, consistent with our previous findings, patients neutrophils were hyper-reactive to stimuli. The activity of nuclear factor erythroid-2-related factor 2 (Nrf2), a master regulator of the antioxidant response, is impaired in circulating neutrophils from chronic periodontitis patients. Although patients' neutrophils exhibit a low reduced glutathione (GSH)/oxidised glutathione (GSSG) ratio and a higher total Nrf2 level, the DNA-binding activity of nuclear Nrf2 remained unchanged relative to healthy controls and had reduced expression of glutamate cysteine ligase catalytic (GCLC), and modifier (GCLM) subunit mRNAs, compared to periodontally healthy subjects neutrophils. Pre-treatment with SFN increased expression of GCLC and GCM, improved intracellular GSH/GSSG ratios and reduced agonist-activated extracellular O2 (. -) production in both dHL60 and primary neutrophils from patients with periodontitis and controls. These findings suggest that a deficiency in Nrf2-dependent pathways may underpin susceptibility to hyper-reactivity in circulating primary neutrophils during chronic periodontitis.

  10. Indirect evidence for a role of a subpopulation of activated neutrophils in the remodelling process after percutaneous coronary intervention

    NARCIS (Netherlands)

    Costa, MA; de Wit, LEA; de Valk, V.; Serrano, P; Wardeh, AJ; Serruys, PW; Sluiter, W

    2001-01-01

    Aim Leukocytes have been implicated in restenosis following percutaneous transluminal coronary angioplasty. We investigated the link between the activated status of circulating neutrophils and restenosis after angioplasty. Methods and Results The population of 108 patients with single, de novo lesio

  11. An Association between Neutrophils and Immunoglobulin Free Light Chains in the Pathogenesis of Chronic Obstructive Pulmonary Disease

    NARCIS (Netherlands)

    Braber, Saskia; Thio, Marco; Blokhttis, Bart R.; Henricks, Paul A. J.; Koelink, Pim J.; Kormelink, Tom Groot; Bezemer, Gillina F. G.; Kerstjens, Huib A. M.; Postma, Dirkje S.; Garssen, Johan; Kraneveld, Aletta D.; Redegeld, Frank A.; Folkerts, Gert

    2012-01-01

    Rationale: Neutrophils are key players in chronic obstructive pulmonary disease (COPD), and increased numbers of neutrophils are present in sputum and lung tissue of patients with COPD. Interestingly, immunoglobulin free light chains (IgLC) are able to prolong the life of neutrophils; therefore, IgL

  12. Inflammatory mechanisms and treatment of obstructive airway diseases with neutrophilic bronchitis.

    Science.gov (United States)

    Simpson, Jodie L; Phipps, Simon; Gibson, Peter G

    2009-10-01

    Obstructive airway diseases such as asthma and chronic obstructive pulmonary disease (COPD) are major global health issues. Although considered as distinct diseases, airway inflammation is a key underlying pathophysiological process in asthma, COPD and bronchiectasis. Persistent neutrophilic airway inflammation (neutrophilic bronchitis) occurs with innate immune activation and is a feature of each of these airway diseases. Little is known about the mechanisms leading to neutrophilic bronchitis and few treatments are effective in reducing neutrophil accumulation in the airways. There is a similar pattern of inflammatory mediator release and toll like receptor 2 expression in asthma, COPD and bronchiectasis. We propose the existence of an active amplification mechanism, an effector arm of the innate immune system, involving toll like receptor 2, operating in persistent neutrophilic bronchitis. Neutrophil persistence in the airways can occur through a number of mechanisms such as impaired apoptosis, efferocytosis and mucus hypersecretion, all of which are impaired in airways disease. Impairment of neutrophil clearance results in a reduced ability to respond to bacterial infection. Persistent activation of airway neutrophils may result in the persistent activation of the innate immune system resulting in further airway insult. Current therapies are limited for the treatment of neutrophilic bronchitis; possible treatments being investigated include theophylline, statins, antagonists of pro-inflammatory cytokines and macrolide antibiotics. Macrolides have shown great promise in their ability to reduce airway inflammation, and can reduce airway neutrophils, levels of CXCL8 and neutrophil proteases in the airways. Studies also show improvements in quality of life and exacerbation rates in airways diseases.

  13. [The participation of neutrophilic mechanisms in the pathogenesis of chronic elevated blood immune complexes].

    Science.gov (United States)

    Bidiuk, M M; Chop'iak, V V; Liubinets', L A; Pavlovich, S I; Nykytiuk, H P; Porokhovs'ka, Z S

    1997-01-01

    For reproduction of chronic hyperimmunocomplexemia model the classic Cochrane C. G., 1973 elaboration was used. The circulating immune complexes (CIC) were identified by precipitation methods, and fixated--by immunofluorescent in endothelium reproduction of aorta, and their clearance organs--liver and spleen. The estimation of neutrophil status was carried out according to rosette-forming neutrophils ability--by latex, zimosane, mieloperoxidasa, NST tests. The growth of large and middle CIC in vessel bed was estimated, their fixation in aorta bifurcation, and also on liver and spleen calls, but their intensivity is less, comparing to aorta endothelium. The neutrophil status was characterised by O-neutrophils growth, strengthening of capturing macrophages function, considerable activation of fermentative polynuclear systems, although reserve possibilities in them grew in less degree. Morphologic investigations allow to speak mediatingly about neutrophils participation in endotheliocytes damage, and also about their ability to secure the mononuclear cells further participation in damaging of aorta walls and partially of liver and spleen.

  14. Leukocyte subsets and neutrophil function after short-term spaceflight

    Science.gov (United States)

    Stowe, R. P.; Sams, C. F.; Mehta, S. K.; Kaur, I.; Jones, M. L.; Feeback, D. L.; Pierson, D. L.

    1999-01-01

    Changes in leukocyte subpopulations and function after spaceflight have been observed but the mechanisms underlying these changes are not well defined. This study investigated the effects of short-term spaceflight (8-15 days) on circulating leukocyte subsets, stress hormones, immunoglobulin levels, and neutrophil function. At landing, a 1.5-fold increase in neutrophils was observed compared with preflight values; lymphocytes were slightly decreased, whereas the results were variable for monocytes. No significant changes were observed in plasma levels of immunoglobulins, cortisol, or adrenocorticotropic hormone. In contrast, urinary epinephrine, norepinephrine, and cortisol were significantly elevated at landing. Band neutrophils were observed in 9 of 16 astronauts. Neutrophil chemotactic assays showed a 10-fold decrease in the optimal dose response after landing. Neutrophil adhesion to endothelial cells was increased both before and after spaceflight. At landing, the expression of MAC-1 was significantly decreased while L-selectin was significantly increased. These functional alterations may be of clinical significance on long-duration space missions.

  15. The role of neutrophils in immune dysfunction during severe inflammation.

    Science.gov (United States)

    Leliefeld, Pieter H C; Wessels, Catharina M; Leenen, Luke P H; Koenderman, Leo; Pillay, Janesh

    2016-03-23

    Critically ill post-surgical, post-trauma and/or septic patients are characterised by severe inflammation. This immune response consists of both a pro- and an anti-inflammatory component. The pro-inflammatory component contributes to (multiple) organ failure whereas occurrence of immune paralysis predisposes to infections. Strikingly, infectious complications arise in these patients despite the presence of a clear neutrophilia. We propose that dysfunction of neutrophils potentially increases the susceptibility to infections or can result in the inability to clear existing infections. Under homeostatic conditions these effector cells of the innate immune system circulate in a quiescent state and serve as the first line of defence against invading pathogens. In severe inflammation, however, neutrophils are rapidly activated, which affects their functional capacities, such as chemotaxis, phagocytosis, intra-cellular killing, NETosis, and their capacity to modulate adaptive immunity. This review provides an overview of the current understanding of neutrophil dysfunction in severe inflammation. We will discuss the possible mechanisms of downregulation of anti-microbial function, suppression of adaptive immunity by neutrophils and the contribution of neutrophil subsets to immune paralysis.

  16. Human Neutrophils Kill Bacillus anthracis.

    Directory of Open Access Journals (Sweden)

    2005-11-01

    Full Text Available Bacillus anthracis spores cause natural infections and are used as biological weapons. Inhalation infection with B. anthracis, the etiological agent of anthrax, is almost always lethal, yet cutaneous infections usually remain localized and resolve spontaneously. Neutrophils are typically recruited to cutaneous but seldom to other forms of anthrax infections, raising the possibility that neutrophils kill B. anthracis. In this study we infected human neutrophils with either spores or vegetative bacteria of a wild-type strain, or strains, expressing only one of the two major virulence factors. The human neutrophils engulfed B. anthracis spores, which germinated intracellularly and were then efficiently killed. Interestingly, neutrophil killing was independent of reactive oxygen species production. We fractionated a human neutrophil granule extract by high-performance liquid chromatography and identified alpha-defensins as the component responsible for B. anthracis killing. These data suggest that the timely recruitment of neutrophils can control cutaneous infections and possibly other forms of B. anthracis infections, and that alpha-defensins play an important role in the potent anti-B. anthracis activity of neutrophils.

  17. Human neutrophils kill Bacillus anthracis.

    Directory of Open Access Journals (Sweden)

    Anne Mayer-Scholl

    2005-11-01

    Full Text Available Bacillus anthracis spores cause natural infections and are used as biological weapons. Inhalation infection with B. anthracis, the etiological agent of anthrax, is almost always lethal, yet cutaneous infections usually remain localized and resolve spontaneously. Neutrophils are typically recruited to cutaneous but seldom to other forms of anthrax infections, raising the possibility that neutrophils kill B. anthracis. In this study we infected human neutrophils with either spores or vegetative bacteria of a wild-type strain, or strains, expressing only one of the two major virulence factors. The human neutrophils engulfed B. anthracis spores, which germinated intracellularly and were then efficiently killed. Interestingly, neutrophil killing was independent of reactive oxygen species production. We fractionated a human neutrophil granule extract by high-performance liquid chromatography and identified alpha-defensins as the component responsible for B. anthracis killing. These data suggest that the timely recruitment of neutrophils can control cutaneous infections and possibly other forms of B. anthracis infections, and that alpha-defensins play an important role in the potent anti-B. anthracis activity of neutrophils.

  18. Human neutrophils kill Bacillus anthracis.

    Science.gov (United States)

    Mayer-Scholl, Anne; Hurwitz, Robert; Brinkmann, Volker; Schmid, Monika; Jungblut, Peter; Weinrauch, Yvette; Zychlinsky, Arturo

    2005-11-01

    Bacillus anthracis spores cause natural infections and are used as biological weapons. Inhalation infection with B. anthracis, the etiological agent of anthrax, is almost always lethal, yet cutaneous infections usually remain localized and resolve spontaneously. Neutrophils are typically recruited to cutaneous but seldom to other forms of anthrax infections, raising the possibility that neutrophils kill B. anthracis. In this study we infected human neutrophils with either spores or vegetative bacteria of a wild-type strain, or strains, expressing only one of the two major virulence factors. The human neutrophils engulfed B. anthracis spores, which germinated intracellularly and were then efficiently killed. Interestingly, neutrophil killing was independent of reactive oxygen species production. We fractionated a human neutrophil granule extract by high-performance liquid chromatography and identified alpha-defensins as the component responsible for B. anthracis killing. These data suggest that the timely recruitment of neutrophils can control cutaneous infections and possibly other forms of B. anthracis infections, and that alpha-defensins play an important role in the potent anti-B. anthracis activity of neutrophils.

  19. Occupational Neutrophilic Asthma

    Directory of Open Access Journals (Sweden)

    Richard Leigh

    1999-01-01

    Full Text Available Occupational asthma is typically associated with an eosinophilic bronchitis. The case of a 41-year-old woman who developed symptoms of asthma after occupational exposure to metal working fluids is reported. The diagnosis of asthma was confirmed by an forced expiratory volume in 1 s (FEV1 of 1.7 (59% predicted, with 11% reversibility after inhaled bronchodilator and a provocation concentration of methacholine to cause a fall in FEV1 of 20% (PC20 of 0.4 mg/mL. Induced sputum examination showed a marked neutrophilia. Over the next six months, serial sputum analyses confirmed the presence of a marked sterile neutrophilic bronchitis during periods of occupational exposure to metal working fluids, which resolved when the patient was away from work and recurred when she returned to work. The sputum findings were mirrored by corresponding changes in spirometry and PC20 methacholine. The findings indicate the occurrence of occupational asthma associated with an intense, sterile neutrophilic bronchitis after exposure to metal working fluids.

  20. Human neutrophil antimicrobial activity.

    Science.gov (United States)

    Thomas, E L; Lehrer, R I; Rest, R F

    1988-01-01

    Polymorphonuclear neutrophilic leukocytes (PMNs) take up opsonized microorganisms into phagosomes that fuse with secretory granules in the PMN cytoplasm to form phagolysosomes. Killing and digestion of microorganisms take place within phagolysosomes. Antimicrobial activities in phagolysosomes are divided into two classes. Oxygen (O2)-dependent mechanisms are expressed when PMNs undergo the "respiratory burst." An NADPH oxidase in the phagolysosome membrane is activated and reduces O2 to superoxide (O2-). O2 reduction is the first step in a series of reactions that produce toxic oxidants. For example, .O2- dismutases to hydrogen peroxide (H2O2), and the azurophil granule enzyme myeloperoxidase catalyzes the oxidation of Cl- by H2O2 to yield hypochlorous acid (HOCl). The reaction of HOCl with ammonia and amines modulates the toxicity of this oxidant. O2-independent antimicrobial mechanisms include the activities of lysosomal proteases, other hydrolytic enzymes, and proteins and peptides that bind to microorganisms and disrupt essential processes or structural components. For example, the bactericidal/permeability-increasing protein, cathepsin G, and the defensins are released into phagolysosomes from the azurophil granules. Proposed mechanisms of action of neutrophil antimicrobial agents, their range of microbial targets, and their possible interactions within phagolysosomes are discussed.

  1. The interaction of Acanthamoeba castellanii cysts with macrophages and neutrophils.

    Science.gov (United States)

    Hurt, Michael; Proy, Vincent; Niederkorn, Jerry Y; Alizadeh, Hassan

    2003-06-01

    Acanthamoeba castellanii, a free-living amoeba, causes a sight-threatening form of keratitis. Even after extensive therapies, corneal damage can be severe, often requiring corneal transplantation to restore vision. However, A. castellanii cysts are not eliminated from the conjunctiva and stroma of humans and can excyst, resulting in infection of the corneal transplant. The aim of this study was to determine whether elements of the innate immune apparatus, neutrophils and macrophages, were capable of detecting and eliminating A. castellanii cysts and to examine the mechanism by which they kill the cysts. Results show that neither innate immune cell is attracted chemotactically to intact cysts, yet both were attracted to lysed cysts. Both macrophages and neutrophils were capable of killing significant numbers of cysts, yet neutrophils were 3-fold more efficient than macrophages. Activation of macrophages with lipopolysaccharide and interferon-gamma did not increase their cytolytic ability. Conditioned medium isolated from macrophages did not lyse the cysts; however, prevention of phagocytosis by cytochalasin D inhibited 100% of macrophage-mediated killing of the cysts. Conditioned medium from neutrophils did kill significant numbers of the cysts, and this killing was blocked by quercetin, a potent inhibitor of myeloperoxidase (MPO). These results indicate that neither macrophages nor neutrophils are chemoattracted to intact cysts, yet both are capable of killing the cysts. Macrophages killed the cysts by phagocytosis, whereas neutrophils killed cysts through the secretion of MPO.

  2. Fetal Circulation

    Science.gov (United States)

    ... Peripheral Artery Disease Venous Thromboembolism Aortic Aneurysm More Fetal Circulation Updated:Oct 18,2016 click to enlarge The ... fetal heart. These two bypass pathways in the fetal circulation make it possible for most fetuses to survive ...

  3. Alpha-1-antitrypsin is produced by human neutrophil granulocytes and their precursors and liberated during granule exocytosis

    DEFF Research Database (Denmark)

    Clemmensen, Stine N; Jacobsen, Lars C; Rørvig, Sara;

    2011-01-01

    . Neutrophils from patients with A1AT-deficiency carrying the (PI)ZZ mutation in the A1AT gene appeared structurally and functionally normal, but A1AT produced in leukocytes of these patients lacked the ability to bind proteases efficiently. We conclude that A1AT generation and release from neutrophils add......Alpha-1-antitrypsin (A1AT) is an important inhibitor of neutrophil proteases including elastase, cathepsin G, and proteinase 3. Transcription profiling data suggest that A1AT is expressed by human neutrophil granulocytes during all developmental stages. A1AT has hitherto only been found associated......1AT is produced at all stages of myeloid maturation in the bone marrow. The production increases as neutrophils enter circulation and increases further upon migration to tissues as observed in skin windows and when blood neutrophils are incubated with granulocyte colony-stimulating factor...

  4. Type I Interferon Transcriptional Signature in Neutrophils and Low-Density Granulocytes Are Associated with Tissue Damage in Malaria

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    Bruno Coelho Rocha

    2015-12-01

    Full Text Available Neutrophils are the most abundant leukocyte population in the bloodstream, the primary compartment of Plasmodium sp. infection. However, the role of these polymorphonuclear cells in mediating either the resistance or the pathogenesis of malaria is poorly understood. We report that circulating neutrophils from malaria patients are highly activated, as indicated by a strong type I interferon transcriptional signature, increased expression of surface activation markers, enhanced release of reactive oxygen species and myeloperoxidase, and a high frequency of low-density granulocytes. The activation of neutrophils was associated with increased levels of serum alanine and aspartate aminotransferases, indicating liver damage. In a rodent malaria model, we observed intense recruitment of neutrophils to liver sinusoids. Neutrophil migration and IL-1β and chemokine expression as well as liver damage were all dependent on type I interferon signaling. The data suggest that type I interferon signaling has a central role in neutrophil activation and malaria pathogenesis.

  5. Mincle activation enhances neutrophil migration and resistance to polymicrobial septic peritonitis

    Science.gov (United States)

    Lee, Wook-Bin; Yan, Ji-Jing; Kang, Ji-Seon; Zhang, Quanri; Choi, Won Young; Kim, Lark Kyun; Kim, Young-Joon

    2017-01-01

    Sepsis is a systemic inflammatory response to bacterial infection. The therapeutic options for treating sepsis are limited. Impaired neutrophil recruitment into the infection site is directly associated with severe sepsis, but the precise mechanism is unclear. Here, we show that Mincle plays a key role in neutrophil migration and resistance during polymicrobial sepsis. Mincle-deficient mice exhibited lower survival rates in experimental sepsis from cecal ligation and puncture and Escherichia coli–induced peritonitis. Mincle deficiency led to higher serum inflammatory cytokine levels and reduced bacterial clearance and neutrophil recruitment. Transcriptome analyses revealed that trehalose dimycolate, a Mincle ligand, reduced the expression of G protein–coupled receptor kinase 2 (GRK2) in neutrophils. Indeed, GRK2 expression was upregulated, but surface expression of the chemokine receptor CXCR2 was downregulated in blood neutrophils from Mincle-deficient mice with septic injury. Moreover, CXCL2-mediated adhesion, chemotactic responses, and F-actin polymerization were reduced in Mincle-deficient neutrophils. Finally, we found that fewer Mincle-deficient neutrophils infiltrated from the blood circulation into the peritoneal fluid in bacterial septic peritonitis compared with wild-type cells. Thus, our results indicate that Mincle plays an important role in neutrophil infiltration and suggest that Mincle signaling may provide a therapeutic target for treating sepsis. PMID:28112221

  6. Altered Innate Immune Responses in Neutrophils from Patients with Well- and Suboptimally Controlled Asthma

    Directory of Open Access Journals (Sweden)

    Francesca S. M. Tang

    2015-01-01

    Full Text Available Background. Respiratory infections are a major cause of asthma exacerbations where neutrophilic inflammation dominates and is associated with steroid refractory asthma. Structural airway cells in asthma differ from nonasthmatics; however it is unknown if neutrophils differ. We investigated neutrophil immune responses in patients who have good (AGood and suboptimal (ASubopt asthma symptom control. Methods. Peripheral blood neutrophils from AGood (ACQ 0.75, n=7, and healthy controls (HC (n=9 were stimulated with bacterial (LPS (1 μg/mL, fMLF (100 nM, and viral (imiquimod (3 μg/mL, R848 (1.5 μg/mL, and poly I:C (10 μg/mL surrogates or live rhinovirus (RV 16 (MOI1. Cell-free supernatant was collected after 1 h for neutrophil elastase (NE and matrix metalloproteinase- (MMP- 9 measurements or after 24 h for CXCL8 release. Results. Constitutive NE was enhanced in AGood neutrophils compared to HC. fMLF stimulated neutrophils from ASubopt but not AGood produced 50% of HC levels. fMLF induced MMP-9 was impaired in ASubopt and AGood compared to HC. fMLF stimulated CXCL8 but not MMP-9 was positively correlated with FEV1 and FEV1/FVC. ASubopt and AGood responded similarly to other stimuli. Conclusions. Circulating neutrophils are different in asthma; however, this is likely to be related to airflow limitation rather than asthma control.

  7. Iodinated contrast media induce neutrophil apoptosis through a mitochondrial and caspase mediated pathway.

    LENUS (Irish Health Repository)

    Fanning, N F

    2012-02-03

    Iodinated contrast media (ICM) can induce apoptosis (programmed cell death) in renal, myocardial and endothelial cells. Following intravascular injection, circulating immune cells are exposed to high concentrations of ICM. As neutrophils constitutively undergo apoptosis we hypothesized that ICM may adversely affect neutrophil survival. Our aim was to investigate the effect of ICM on neutrophil apoptosis. Neutrophils were isolated from healthy subjects and cultured in vitro with ionic (diatrizoate and ioxaglate) and non-ionic (iohexol and iotrolan) ICM. The effect of ICM on neutrophil apoptosis in both unstimulated and lipopolysaccharide-stimulated neutrophils was determined by annexin V flow cytometry. The influence of physicochemical properties of the different ICM on apoptosis of neutrophils was also studied. We further investigated the effects of ICM on key intracellular signal pathways, including p38 mitogen-activated protein kinase (MAPK) by Western blotting, and mitochondrial depolarization and caspase activity by flow cytometry. Isoiodine concentrations (20 mg ml(-1)) of ionic (diatrizoate 69.6+\\/-2.9%; ioxaglate 58.9+\\/-2.0%) and non-ionic (iohexol 57.3+\\/-2.9%; iotrolan 57.1+\\/-2.6%) ICM significantly induced neutrophil apoptosis over control levels (47.7+\\/-1.4%). The apoptotic effect of ICM was influenced by their chemical structure, with ionic ICM having a more significant (p<0.01) apoptotic effect than non-ionic ICM (p<0.05). Furthermore, ICM reversed the anti-apoptotic effect of lipopolysaccharide (1000 ng ml(-1)) treated neutrophils to control levels (23.0+\\/-3.5% to 61.2+\\/-5.3%; n=4; p<0.05). These agents induce apoptosis through a p38 MAPK independent pathway that results in mitochondrial depolarization, and is dependent on caspase activation. As neutrophils play a central role in host response to infection and injury, ICM, through induction of neutrophil apoptosis, could have a significant deleterious effect on host immune defence and

  8. Neutrophilic dermatosis of dorsal hands

    Directory of Open Access Journals (Sweden)

    S Kaur

    2015-01-01

    Full Text Available Sweet′s syndrome is characterized by erythematous tender nodules and plaques over face and extremities. Fever, leukocytosis with neutrophilia, and a neutrophilic infiltrate in the dermis are characteristic features. Neutrophilic dermatosis of dorsal hands is a rare localized variant of Sweet′s syndrome occurring predominantly over dorsa of hands. Various degrees of vascular damage may be observed on histopathology of these lesions. Both Sweet′s syndrome and its dorsal hand variant have been reported in association with malignancies, inflammatory bowel diseases, and drugs. We report a patient with neutrophilic dermatoses of dorsal hands associated with erythema nodosum. He showed an excellent response to corticosteroids and dapsone.

  9. Platelet-neutrophil complex formation-a detailed in vitro analysis of murine and human blood samples.

    Science.gov (United States)

    Mauler, Maximilian; Seyfert, Julia; Haenel, David; Seeba, Hannah; Guenther, Janine; Stallmann, Daniela; Schoenichen, Claudia; Hilgendorf, Ingo; Bode, Christoph; Ahrens, Ingo; Duerschmied, Daniel

    2016-05-01

    Platelets form complexes with neutrophils during inflammatory processes. These aggregates migrate into affected tissues and also circulate within the organism. Several studies have evaluated platelet-neutrophil complexes as a marker of cardiovascular diseases in human and mouse. Although multiple publications have reported platelet-neutrophil complex counts, we noticed that different methods were used to analyze platelet-neutrophil complex formation, resulting in significant differences, even in baseline values. We established a protocol for platelet-neutrophil complex measurement with flow cytometry in murine and human whole blood samples. In vitro platelet-neutrophil complex formation was stimulated with ADP or PMA. We tested the effect of different sample preparation steps and cytometer settings on platelet-neutrophil complex detection and noticed false-positive counts with increasing acquisition speed. Platelet-neutrophil complex formation depends on platelet P-selectin expression, and antibody blocking of P-selectin consequently prevented ADP-induced platelet-neutrophil complex formation. These findings may help generating more comparable data among different research groups that examine platelet-neutrophil complexes as a marker for cardiovascular disease and novel therapeutic interventions.

  10. Mycobacterium abscessus induces a limited pattern of neutrophil activation that promotes pathogen survival.

    Directory of Open Access Journals (Sweden)

    Kenneth C Malcolm

    Full Text Available Mycobacterium abscessus is a rapidly growing mycobacterium increasingly detected in the neutrophil-rich environment of inflamed tissues, including the cystic fibrosis airway. Studies of the immune reaction to M. abscessus have focused primarily on macrophages and epithelial cells, but little is known regarding the neutrophil response despite the predominantly neutrophillic inflammation typical of these infections. In the current study, human neutrophils released less superoxide anion in response to M. abscessus than to Staphylococcus aureus, a pathogen that shares common sites of infection. Exposure to M. abscessus induced neutrophil-specific chemokine and proinflammatory cytokine genes. Although secretion of these protein products was confirmed, the quantity of cytokines released, and both the number and level of gene induction, was reduced compared to S. aureus. Neutrophils mediated killing of M. abscessus, but phagocytosis was reduced when compared to S. aureus, and extracellular DNA was detected in response to both bacteria, consistent with extracellular trap formation. In addition, M. abscessus did not alter cell death compared to unstimulated cells, while S. aureus enhanced necrosis and inhibited apoptosis. However, neutrophils augment M. abscessus biofilm formation. The response of neutrophils to M. abscessus suggests that the mycobacterium exploits neutrophil-rich settings to promote its survival and that the overall neutrophil response was reduced compared to S. aureus. These studies add to our understanding of M. abscessus virulence and suggest potential targets of therapy.

  11. Anti-neutrophil cytoplasmic antibodies stimulate release of neutrophil microparticles.

    LENUS (Irish Health Repository)

    Hong, Ying

    2012-01-01

    The mechanisms by which anti-neutrophil cytoplasmic antibodies (ANCAs) may contribute to the pathogenesis of ANCA-associated vasculitis are not well understood. In this study, both polyclonal ANCAs isolated from patients and chimeric proteinase 3-ANCA induced the release of neutrophil microparticles from primed neutrophils. These microparticles expressed a variety of markers, including the ANCA autoantigens proteinase 3 and myeloperoxidase. They bound endothelial cells via a CD18-mediated mechanism and induced an increase in endothelial intercellular adhesion molecule-1 expression, production of endothelial reactive oxygen species, and release of endothelial IL-6 and IL-8. Removal of the neutrophil microparticles by filtration or inhibition of reactive oxygen species production with antioxidants abolished microparticle-mediated endothelial activation. In addition, these microparticles promoted the generation of thrombin. In vivo, we detected more neutrophil microparticles in the plasma of children with ANCA-associated vasculitis compared with that in healthy controls or those with inactive vasculitis. Taken together, these results support a role for neutrophil microparticles in the pathogenesis of ANCA-associated vasculitis, potentially providing a target for future therapeutics.

  12. Chemotactic Activity on Human Neutrophils to Streptococcus mutans

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    Tetiana Haniastuti

    2013-07-01

    Full Text Available Objective: The aim of this study was to evaluate chemotactic activity o neutrophil to S. mutans. Chemotaxis assay was performed in blind well chambers. Materials and Methods: Hanks balanced salt solution (HBSS containing 106 S. mutans,  108 S. mutans, 10-8 M fMLP, or HBSS alone were placed in the lower wells of the chamber and covered with polycorbonate membrane filter. Neutrophils suspension (2x105 cells was then placed in the upper compartment. After incubation for 60 mins at 37ºC in a humidified atmosphere with 5% CO2, the filters were removed and stained with Giemsa. Result: ANOVA revealed statistically significant differences among groups (p<0.05, indicating that S. mutans induced neutrophils chemotaxis. The number of neutrophils migration in response to 108 S. mutans and 106 S. mutans were signifiantly greater compared to fMLP (p<0.05. Conclusion: S. mutans may activate human neutrophils, resulting in the chemotaxis of the neutrophils.DOI: 10.14693/jdi.v16i2.99

  13. Mechanisms of Degranulation in Neutrophils

    Directory of Open Access Journals (Sweden)

    Lacy Paige

    2006-09-01

    Full Text Available Abstract Neutrophils are critical inflammatory cells that cause tissue damage in a range of diseases and disorders. Being bone marrow-derived white blood cells, they migrate from the bloodstream to sites of tissue inflammation in response to chemotactic signals and induce inflammation by undergoing receptor-mediated respiratory burst and degranulation. Degranulation from neutrophils has been implicated as a major causative factor in pulmonary disorders, including severe asphyxic episodes of asthma. However, the mechanisms that control neutrophil degranulation are not well understood. Recent observations indicate that granule release from neutrophils depends on activation of intracellular signalling pathways, including β-arrestins, the Rho guanosine triphosphatase Rac2, soluble NSF attachment protein (SNAP receptors, the src family of tyrosine kinases, and the tyrosine phosphatase MEG2. Some of these observations suggest that degranulation from neutrophils is selective and depends on nonredundant signalling pathways. This review focuses on new findings from the literature on the mechanisms that control the release of granule-derived mediators from neutrophils.

  14. Respiratory syncytial virus fusion protein promotes TLR-4-dependent neutrophil extracellular trap formation by human neutrophils.

    Directory of Open Access Journals (Sweden)

    Giselle A Funchal

    Full Text Available Acute viral bronchiolitis by Respiratory Syncytial Virus (RSV is the most common respiratory illness in children in the first year of life. RSV bronchiolitis generates large numbers of hospitalizations and an important burden to health systems. Neutrophils and their products are present in the airways of RSV-infected patients who developed increased lung disease. Neutrophil Extracellular Traps (NETs are formed by the release of granular and nuclear contents of neutrophils in the extracellular space in response to different stimuli and recent studies have proposed a role for NETs in viral infections. In this study, we show that RSV particles and RSV Fusion protein were both capable of inducing NET formation by human neutrophils. Moreover, we analyzed the mechanisms involved in RSV Fusion protein-induced NET formation. RSV F protein was able to induce NET release in a concentration-dependent fashion with both neutrophil elastase and myeloperoxidase expressed on DNA fibers and F protein-induced NETs was dismantled by DNase treatment, confirming that their backbone is chromatin. This viral protein caused the release of extracellular DNA dependent on TLR-4 activation, NADPH Oxidase-derived ROS production and ERK and p38 MAPK phosphorylation. Together, these results demonstrate a coordinated signaling pathway activated by F protein that led to NET production. The massive production of NETs in RSV infection could aggravate the inflammatory symptoms of the infection in young children and babies. We propose that targeting the binding of TLR-4 by F protein could potentially lead to novel therapeutic approaches to help control RSV-induced inflammatory consequences and pathology of viral bronchiolitis.

  15. AUTOINFLAMMATORY PUSTULAR NEUTROPHILIC DISEASES

    Science.gov (United States)

    Naik, Haley B.; Cowen, Edward W.

    2013-01-01

    SYNOPSIS The inflammatory pustular dermatoses constitute a spectrum of non-infectious conditions ranging from localized involvement to generalized disease with associated acute systemic inflammation and multi-organ involvement. Despite the variability in extent and severity of cutaneous presentation, each of these diseases is characterized by non-infectious neutrophilic intra-epidermal microabscesses. Many share systemic findings including fever, elevated inflammatory markers, inflammatory bowel disease and/or osteoarticular involvement, suggesting potential common pathogenic links (Figure 1). The recent discoveries of several genes responsible for heritable pustular diseases have revealed a distinct link between pustular skin disease and regulation of innate immunity. These genetic advances have led to a deeper exploration of common pathways in pustular skin disease and offer the potential for a new era of biologic therapy which targets these shared pathways. This chapter provides a new categorization of inflammatory pustular dermatoses in the context of recent genetic and biologic insights. We will discuss recently-described monogenic diseases with pustular phenotypes, including deficiency of IL-1 receptor antagonist (DIRA), deficiency of the IL-36 receptor antagonist (DITRA), CARD14-associated pustular psoriasis (CAMPS), and pyogenic arthritis, pyoderma gangrenosum, acne (PAPA). We will then discuss how these new genetic advancements may inform how we view previously described pustular diseases, including pustular psoriasis and its clinical variants, with a focus on historical classification by clinical phenotype. PMID:23827244

  16. Impaired coronary microcirculation in type 2 diabetic patients is associated with elevated circulating regulatory T cells and reduced number of IL-21R⁺ T cells

    DEFF Research Database (Denmark)

    von Scholten, Bernt Johan; Rosendahl, Alexander; Hasbak, Philip

    2016-01-01

    BACKGROUND: Low-grade systemic inflammation is considered to participate in the progression of type 2 diabetes (T2D) and in diabetic complications. METHODS: To determine if circulating leukocytes were abnormally regulated in T2D patients, 8-color flow-cytometry (FACS) analysis was performed...... characterized by reduced overall T cell, Th17, IL-21R(+), Treg's and TLR4(+) T cells, while the monocyte population showed enhanced TLR4 expression. Further, our data revealed reduced M1-like CD11c expression in T2D which was associated with impaired CFR. In contrast, we show, for the first time in T2D...

  17. Polymorphonuclear neutrophils: an effective antimicrobial force.

    Science.gov (United States)

    Sawyer, D W; Donowitz, G R; Mandell, G L

    1989-01-01

    The production and deployment of polymorphonuclear neutrophils (PMNs) are under close regulation. PMNs interact through cytokines with a number of cell types, including macrophages, lymphocytes, and endothelial cells. PMNs are guided by bacterial products and cytokines to target sites, where microbes are recognized and killed. Killing occurs through oxygen-dependent and oxygen-independent mechanisms. The frequent and severe infections seen in patients with defects (either congenital or acquired) in PMN function demonstrate the importance of PMNs in host defense against infection. PMNs are potent inflammatory cells and can exacerbate disease states such as myocardial ischemia, gram-negative bacterial sepsis, and the adult respiratory distress syndrome.

  18. Nearshore circulation

    NARCIS (Netherlands)

    Battjes, J.A.; Sobey, R.J.; Stive, M.J.F.

    1990-01-01

    Shelf circulation is driven primarily by wind- and tide-induced forces. It is laterally only weakly constrained so that the geostrophic (Coriolis) acceleration is manifest in the response. Nearshore circulation on the other hand is dominated by wave-induced forces associated with shallow-water. wave

  19. CRTH2 is a critical regulator of neutrophil migration and resistance to polymicrobial sepsis.

    Science.gov (United States)

    Ishii, Makoto; Asano, Koichiro; Namkoong, Ho; Tasaka, Sadatomo; Mizoguchi, Kosuke; Asami, Takahiro; Kamata, Hirofumi; Kimizuka, Yoshifumi; Fujiwara, Hiroshi; Funatsu, Yohei; Kagawa, Shizuko; Miyata, Jun; Ishii, Ken; Nakamura, Masataka; Hirai, Hiroyuki; Nagata, Kinya; Kunkel, Steven L; Hasegawa, Naoki; Betsuyaku, Tomoko

    2012-06-01

    Although arachidonic acid cascade has been shown to be involved in sepsis, little is known about the role of PGD(2) and its newly found receptor, chemoattractant receptor-homologous molecule expressed on Th2 cells (CRTH2), on the septic response. Severe sepsis is associated with the failure of neutrophil migration. To investigate whether CRTH2 influences neutrophil recruitment and the lethality during sepsis, sepsis was induced by cecal ligation and puncture (CLP) surgery in mice. CRTH2 knockout (CRTH2(-/-)) mice were highly resistant to CLP-induced sepsis, which was associated with lower bacterial load and lower production of TNF-α, IL-6, and CCL3. IL-10, an anti-inflammatory cytokine, was higher in CRTH2(-/-) mice, blunting CLP-induced lethality in CRTH2(-/-) mice. Neutrophil accumulation in the peritoneum was more pronounced after CLP in CRTH2(-/-) mice, which was associated with higher CXCR2 levels in circulating neutrophils. Furthermore, sepsis caused a decrease in the level of acetylation of histone H3, an activation mark, at the CXCR2 promoter in wild-type neutrophils, suggesting that CXCR2 expression levels are epigenetically regulated. Finally, both pharmacological depletion of neutrophils and inhibition of CXCR2 abrogated the survival benefit in CRTH2(-/-) mice. These results demonstrate that genetic ablation of CRTH2 improved impaired neutrophil migration and survival during severe sepsis, which was mechanistically associated with epigenetic-mediated CXCR2 expression. Thus, CRTH2 is a potential therapeutic target for polymicrobial sepsis.

  20. Infectious Progeny of 2009 A (H1N1) Influenza Virus Replicated in and Released from Human Neutrophils.

    Science.gov (United States)

    Zhang, Zhang; Huang, Tao; Yu, Feiyuan; Liu, Xingmu; Zhao, Conghui; Chen, Xueling; Kelvin, David J; Gu, Jiang

    2015-12-07

    Various reports have indicated that a number of viruses could infect neutrophils, but the multiplication of viruses in neutrophils was abortive. Based on our previous finding that avian influenza viral RNA and proteins were present in the nucleus of infected human neutrophils in vivo, we investigated the possibility of 2009 A (H1N1) influenza viral synthesis in infected neutrophils and possible release of infectious progeny from host cells. In this study we found that human neutrophils in vitro without detectable level of sialic acid expression could be infected by this virus strain. We also show that the infected neutrophils can not only synthesize 2009 A (H1N1) viral mRNA and proteins, but also produce infectious progeny. These findings suggest that infectious progeny of 2009 A (H1N1) influenza virus could be replicated in and released from human neutrophils with possible clinical implications.

  1. Lutzomyia longipalpis saliva drives apoptosis and enhances parasite burden in neutrophils.

    Science.gov (United States)

    Prates, Deboraci Brito; Araújo-Santos, Théo; Luz, Nívea Farias; Andrade, Bruno B; França-Costa, Jaqueline; Afonso, Lilian; Clarêncio, Jorge; Miranda, José Carlos; Bozza, Patrícia T; Dosreis, George A; Brodskyn, Cláudia; Barral-Netto, Manoel; Borges, Valéria Matos; Borges, Valéria de Matos; Barral, Aldina

    2011-09-01

    Neutrophils are considered the host's first line of defense against infections and have been implicated in the immunopathogenesis of Leishmaniasis. Leishmania parasites are inoculated alongside vectors' saliva, which is a rich source of pharmacologically active substances that interfere with host immune response. In the present study, we tested the hypothesis that salivary components from Lutzomyia longipalpis, an important vector of visceral Leishmaniasis, enhance neutrophil apoptosis. Murine inflammatory peritoneal neutrophils cultured in the presence of SGS presented increased surface expression of FasL and underwent caspase-dependent and FasL-mediated apoptosis. This proapoptosis effect of SGS on neutrophils was abrogated by pretreatment with protease as well as preincubation with antisaliva antibodies. Furthermore, in the presence of Leishmania chagasi, SGS also increased apoptosis on neutrophils and increased PGE(2) release and decreased ROS production by neutrophils, while enhancing parasite viability inside these cells. The increased parasite burden was abrogated by treatment with z-VAD, a pan caspase inhibitor, and NS-398, a COX-2 inhibitor. In the presence of SGS, Leishmania-infected neutrophils produced higher levels of MCP-1 and attracted a high number of macrophages by chemotaxis in vitro assays. Both of these events were abrogated by pretreatment of neutrophils with bindarit, an inhibitor of CCL2/MCP-1 expression. Taken together, our data support the hypothesis that vector salivary proteins trigger caspase-dependent and FasL-mediated apoptosis, thereby favoring Leishmania survival inside neutrophils, which may represent an important mechanism for the establishment of Leishmania infection.

  2. Neutrophils and Granulocytic MDSC: The Janus God of Cancer Immunotherapy

    Directory of Open Access Journals (Sweden)

    Serena Zilio

    2016-09-01

    Full Text Available Neutrophils are the most abundant circulating blood cell type in humans, and are the first white blood cells recruited at the inflammation site where they orchestrate the initial immune response. Although their presence at the tumor site was recognized in the 1970s, until recently these cells have been neglected and considered to play just a neutral role in tumor progression. Indeed, in recent years neutrophils have been recognized to play a dual role in tumor development by either assisting the growth, angiogenesis, invasion, and metastasis or by exerting tumoricidal action directly via the secretion of antitumoral compounds, or indirectly via the orchestration of antitumor immunity. Understanding the biology of these cells and influencing their polarization in the tumor micro- and macro-environment may be the key for the development of new therapeutic strategies, which may finally hold the promise of an effective immunotherapy for cancer.

  3. Neutrophils and Granulocytic MDSC: The Janus God of Cancer Immunotherapy.

    Science.gov (United States)

    Zilio, Serena; Serafini, Paolo

    2016-09-09

    Neutrophils are the most abundant circulating blood cell type in humans, and are the first white blood cells recruited at the inflammation site where they orchestrate the initial immune response. Although their presence at the tumor site was recognized in the 1970s, until recently these cells have been neglected and considered to play just a neutral role in tumor progression. Indeed, in recent years neutrophils have been recognized to play a dual role in tumor development by either assisting the growth, angiogenesis, invasion, and metastasis or by exerting tumoricidal action directly via the secretion of antitumoral compounds, or indirectly via the orchestration of antitumor immunity. Understanding the biology of these cells and influencing their polarization in the tumor micro- and macro-environment may be the key for the development of new therapeutic strategies, which may finally hold the promise of an effective immunotherapy for cancer.

  4. Neutrophils and Granulocytic MDSC: The Janus God of Cancer Immunotherapy

    Science.gov (United States)

    Zilio, Serena; Serafini, Paolo

    2016-01-01

    Neutrophils are the most abundant circulating blood cell type in humans, and are the first white blood cells recruited at the inflammation site where they orchestrate the initial immune response. Although their presence at the tumor site was recognized in the 1970s, until recently these cells have been neglected and considered to play just a neutral role in tumor progression. Indeed, in recent years neutrophils have been recognized to play a dual role in tumor development by either assisting the growth, angiogenesis, invasion, and metastasis or by exerting tumoricidal action directly via the secretion of antitumoral compounds, or indirectly via the orchestration of antitumor immunity. Understanding the biology of these cells and influencing their polarization in the tumor micro- and macro-environment may be the key for the development of new therapeutic strategies, which may finally hold the promise of an effective immunotherapy for cancer. PMID:27618112

  5. Lactoferrin Suppresses Neutrophil Extracellular Traps Release in Inflammation.

    Science.gov (United States)

    Okubo, Koshu; Kamiya, Mako; Urano, Yasuteru; Nishi, Hiroshi; Herter, Jan M; Mayadas, Tanya; Hirohama, Daigoro; Suzuki, Kazuo; Kawakami, Hiroshi; Tanaka, Mototsugu; Kurosawa, Miho; Kagaya, Shinji; Hishikawa, Keiichi; Nangaku, Masaomi; Fujita, Toshiro; Hayashi, Matsuhiko; Hirahashi, Junichi

    2016-08-01

    Neutrophils are central players in the innate immune system. They generate neutrophil extracellular traps (NETs), which protect against invading pathogens but are also associated with the development of autoimmune and/or inflammatory diseases and thrombosis. Here, we report that lactoferrin, one of the components of NETs, translocated from the cytoplasm to the plasma membrane and markedly suppressed NETs release. Furthermore, exogenous lactoferrin shrunk the chromatin fibers found in released NETs, without affecting the generation of oxygen radicals, but this failed after chemical removal of the positive charge of lactoferrin, suggesting that charge-charge interactions between lactoferrin and NETs were required for this function. In a model of immune complex-induced NET formation in vivo, intravenous lactoferrin injection markedly reduced the extent of NET formation. These observations suggest that lactoferrin serves as an intrinsic inhibitor of NETs release into the circulation. Thus, lactoferrin may represent a therapeutic lead for controlling NETs release in autoimmune and/or inflammatory diseases.

  6. Simulation and Analysis of Tethering Behavior of Neutrophils with Pseudopods.

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    Anne D Rocheleau

    Full Text Available P-selectin and P-selectin glycoprotein ligand-1 (PSGL-1 play important roles in mediating the inflammatory cascade. Selectin kinetics, together with neutrophil hydrodynamics, regulate the fundamental adhesion cascade of cell tethering and rolling on the endothelium. The current study uses the Multiscale Adhesive Dynamics computational model to simulate, for the first time, the tethering and rolling behavior of pseudopod-containing neutrophils as mediated by P-selectin/PSGL-1 bonds. This paper looks at the effect of including P-selectin/PSGL-1 adhesion kinetics. The parameters examined included the shear rate, adhesion on-rate, initial neutrophil position, and receptor number sensitivity. The outcomes analyzed included types of adhesive behavior observed, tether rolling distance and time, number of bonds formed during an adhesive event, contact area, and contact time. In contrast to the hydrodynamic model, P-selectin/PSGL-1 binding slows the neutrophil's translation in the direction of flow and causes the neutrophil to swing around perpendicular to flow. Several behaviors were observed during the simulations, including tethering without firm adhesion, tethering with downstream firm adhesion, and firm adhesion upon first contact with the endothelium. These behaviors were qualitatively consistent with in vivo data of murine neutrophils with pseudopods. In the simulations, increasing shear rate, receptor count, and bond formation rate increased the incidence of firm adhesion upon first contact with the endothelium. Tethering was conserved across a range of physiological shear rates and was resistant to fluctuations in the number of surface PSGL-1 molecules. In simulations where bonding occurred, interaction with the side of the pseudopod, rather than the tip, afforded more surface area and greater contact time with the endothelial wall.

  7. Cigarette smoke-induced damage-associated molecular pattern release from necrotic neutrophils triggers proinflammatory mediator release.

    Science.gov (United States)

    Heijink, Irene H; Pouwels, Simon D; Leijendekker, Carin; de Bruin, Harold G; Zijlstra, G Jan; van der Vaart, Hester; ten Hacken, Nick H T; van Oosterhout, Antoon J M; Nawijn, Martijn C; van der Toorn, Marco

    2015-05-01

    Cigarette smoking, the major causative factor for the development of chronic obstructive pulmonary disease, is associated with neutrophilic airway inflammation. Cigarette smoke (CS) exposure can induce a switch from apoptotic to necrotic cell death in airway epithelium. Therefore, we hypothesized that CS promotes neutrophil necrosis with subsequent release of damage-associated molecular patterns (DAMPs), including high mobility group box 1 (HMGB1), alarming the innate immune system. We studied the effect of smoking two cigarettes on sputum neutrophils in healthy individuals and of 5-day CS or air exposure on neutrophil counts, myeloperoxidase, and HMGB1 levels in bronchoalveolar lavage fluid of BALB/c mice. In human peripheral blood neutrophils, mitochondrial membrane potential, apoptosis/necrosis markers, caspase activity, and DAMP release were studied after CS exposure. Finally, we assessed the effect of neutrophil-derived supernatants on the release of chemoattractant CXCL8 in normal human bronchial epithelial cells. Cigarette smoking caused a significant decrease in sputum neutrophil numbers after 3 hours. In mice, neutrophil counts were significantly increased 16 hours after repeated CS exposure but reduced 2 hours after an additional exposure. In vitro, CS induced necrotic neutrophil cell death, as indicated by mitochondrial dysfunction, inhibition of apoptosis, and DAMP release. Supernatants from CS-treated neutrophils significantly increased the release of CXCL8 in normal human bronchial epithelial cells. Together, these observations show, for the first time, that CS exposure induces neutrophil necrosis, leading to DAMP release, which may amplify CS-induced airway inflammation by promoting airway epithelial proinflammatory responses.

  8. Ca2+ response in neutrophils after exposure to bacterial N-formyl-methionyl-leucyl-phenylalanine: delayed response in ulcerative colitis

    DEFF Research Database (Denmark)

    Vainer, Ben; Lamberth, Kasper; Brimnes, Jens;

    2003-01-01

    In acute stages of ulcerative colitis (UC), neutrophils migrate from the circulation into inflamed colonic tissue, initiated by yet unknown stimuli. The bacterial peptide N-formyl-methionyl-leucyl-phenylalanine (FMLP) is a component of the surface membrane of colonic bacteria such as Escherichia...... coli and stimulates Ca2+ influx into neutrophils, reflecting the fact that ionized calcium is an important secondary messenger for several neutrophil functions, including locomotion, phagocytosis and free oxygen radical production. Recent studies have revealed that Ca2+ dependent ICAM-1/beta 2-integrin...... mediated neutrophil migration is impaired in UC patients. The aim of the present work was to study the influx of Ca2+ into peripheral blood neutrophils of UC patients after exposure to FMLP and after binding of either beta 2-integrins or intercellular adhesion molecule-1 (ICAM-1)....

  9. Ensemble models of neutrophil trafficking in severe sepsis.

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    Sang Ok Song

    Full Text Available A hallmark of severe sepsis is systemic inflammation which activates leukocytes and can result in their misdirection. This leads to both impaired migration to the locus of infection and increased infiltration into healthy tissues. In order to better understand the pathophysiologic mechanisms involved, we developed a coarse-grained phenomenological model of the acute inflammatory response in CLP (cecal ligation and puncture-induced sepsis in rats. This model incorporates distinct neutrophil kinetic responses to the inflammatory stimulus and the dynamic interactions between components of a compartmentalized inflammatory response. Ensembles of model parameter sets consistent with experimental observations were statistically generated using a Markov-Chain Monte Carlo sampling. Prediction uncertainty in the model states was quantified over the resulting ensemble parameter sets. Forward simulation of the parameter ensembles successfully captured experimental features and predicted that systemically activated circulating neutrophils display impaired migration to the tissue and neutrophil sequestration in the lung, consequently contributing to tissue damage and mortality. Principal component and multiple regression analyses of the parameter ensembles estimated from survivor and non-survivor cohorts provide insight into pathologic mechanisms dictating outcome in sepsis. Furthermore, the model was extended to incorporate hypothetical mechanisms by which immune modulation using extracorporeal blood purification results in improved outcome in septic rats. Simulations identified a sub-population (about 18% of the treated population that benefited from blood purification. Survivors displayed enhanced neutrophil migration to tissue and reduced sequestration of lung neutrophils, contributing to improved outcome. The model ensemble presented herein provides a platform for generating and testing hypotheses in silico, as well as motivating further experimental

  10. Functional neutrophils from human ES cells

    OpenAIRE

    Sweeney, Colin L; Malech, Harry L.

    2009-01-01

    In this issue of Blood, Yokoyama and colleagues demonstrate in vitro differentiation of hESCs into mature neutrophils with functional capabilities (chemotaxis, phagocytosis, microbicidal oxidase activity, and bacterial killing) approaching or equal to that of normal peripheral blood neutrophils.

  11. Neutrophil biomarkers predict response to therapy with tumor necrosis factor inhibitors in rheumatoid arthritis.

    Science.gov (United States)

    Wright, Helen L; Cox, Trevor; Moots, Robert J; Edwards, Steven W

    2017-03-01

    Neutrophils are implicated in the pathology of rheumatoid arthritis (RA), but the mechanisms regulating their activation are largely unknown. RA is a heterogeneous disease, and whereas many patients show clinical improvement during TNF inhibitor (TNFi) therapy, a significant proportion fails to respond. In vitro activation of neutrophils with agents, including TNF, results in rapid and selective changes in gene expression, but how neutrophils contribute to TNF signaling in RA and whether TNFi sensitivity involves differential neutrophil responses are unknown. With the use of RNA sequencing (RNA-Seq), we analyzed blood neutrophils from 20 RA patients, pre-TNFi therapy, to identify biomarkers of response, measured by a decrease in disease activity score based on 28 joint count (DAS28), 12 wk post-therapy. Biomarkers were validated by quantitative PCR (qPCR) of blood neutrophils from 2 further independent cohorts of RA patients: 16 pre-TNFi and 16 predisease-modifying anti-rheumatic drugs (DMARDs). Twenty-three neutrophil transcripts predicted a 12-wk response to TNFi: 10 (IFN-regulated) genes predicting a European League against Rheumatism (EULAR) good response and 13 different genes [neutrophil granule protein (NGP) genes] predicting a nonresponse. Statistical analysis indicated a predictive sensitivity and specificity of each gene in the panel of >80%, with some 100% specific. A combination of 3 genes [cytidine monophosphate kinase 2 (CMPK2), IFN-induced protein with tetratricopeptide repeats 1B (IFIT1B), and RNASE3] had the greatest predictive power [area under the curve (AUC) 0.94]. No correlation was found for a response to DMARDs. We conclude that this panel of genes is selective for predicting a response to TNFi and is not a surrogate marker for disease improvement. We also show that in RA, there is great plasticity in neutrophil phenotype, with circulating cells expressing genes normally only expressed in more immature cells.

  12. Neutrophil activation during acetaminophen hepatotoxicity and repair in mice and humans

    Energy Technology Data Exchange (ETDEWEB)

    Williams, C. David; Bajt, Mary Lynn [Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS (United States); Sharpe, Matthew R. [Department of Internal Medicine, University of Kansas Hospital, Kansas City, KS (United States); McGill, Mitchell R. [Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS (United States); Farhood, Anwar [Department of Pathology, St. David' s North Austin Medical Center, Austin, TX 78756 (United States); Jaeschke, Hartmut, E-mail: hjaeschke@kumc.edu [Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS (United States)

    2014-03-01

    Following acetaminophen (APAP) overdose there is an inflammatory response triggered by the release of cellular contents from necrotic hepatocytes into the systemic circulation which initiates the recruitment of neutrophils into the liver. It has been demonstrated that neutrophils do not contribute to APAP-induced liver injury, but their role and the role of NADPH oxidase in injury resolution are controversial. C57BL/6 mice were subjected to APAP overdose and neutrophil activation status was determined during liver injury and liver regeneration. Additionally, human APAP overdose patients (ALT: > 800 U/L) had serial blood draws during the injury and recovery phases for the determination of neutrophil activation. Neutrophils in the peripheral blood of mice showed an increasing activation status (CD11b expression and ROS priming) during and after the peak of injury but returned to baseline levels prior to complete injury resolution. Hepatic sequestered neutrophils showed an increased and sustained CD11b expression, but no ROS priming was observed. Confirming that NADPH oxidase is not critical to injury resolution, gp91{sup phox}−/− mice following APAP overdose displayed no alteration in injury resolution. Peripheral blood from APAP overdose patients also showed increased neutrophil activation status after the peak of liver injury and remained elevated until discharge from the hospital. In mice and humans, markers of activation, like ROS priming, were increased and sustained well after active liver injury had subsided. The similar findings between surviving patients and mice indicate that neutrophil activation may be a critical event for host defense or injury resolution following APAP overdose, but not a contributing factor to APAP-induced injury. - Highlights: • Neutrophil (PMN) function increases during liver repair after acetaminophen overdose. • Liver repair after acetaminophen (APAP)-overdose is not dependent on NADPH oxidase. • Human PMNs do not appear

  13. Neutrophil apoptosis in the lung after hemorrhage or endotoxemia: apoptosis and migration are independent of IL-1beta.

    Science.gov (United States)

    Parsey, M V; Kaneko, D; Shenkar, R; Abraham, E

    1999-05-01

    Hemorrhage and endotoxemia are associated with neutrophil accumulation in the lungs and the development of acute inflammatory lung injury. Because alterations in the rate of apoptosis may affect the number and function of neutrophils in the lungs, we determined the percentage of neutrophils undergoing apoptosis in the lungs of control, hemorrhaged, or endotoxemic mice. In control mice, 18.5 +/- 1.2% of pulmonary neutrophils were apoptotic. The proportion of apoptotic neutrophils in the lungs was significantly decreased 1 h after hemorrhage (6.5 +/- 1.6%, P < 0.01 compared to control) or endotoxemia (7.0 +/- 0.9%, P < 0.01 compared to control). Between 1 and 24 h after endotoxemia or hemorrhage, the proportion of apoptotic neutrophils in the lung remained significantly depressed compared to that in control, unmanipulated mice. By 48 h, the proportion of apoptotic neutrophils returned to baseline levels in the lungs of hemorrhaged (21.4 +/- 1.4%) or endotoxemic (16.4 +/- 1. 6%) mice. Lung neutrophil IL-1beta mRNA was significantly increased from that of control mice [i.e., 0.12 +/- 0.06 relative absorbance units (RAU)] 1 h after hemorrhage (5.19 +/- 0.068 RAU, P < 0.05 compared to control) or endotoxemia (8.90 +/- 1.53 RAU, P < 0.01 compared to control). In IL-1beta-deficient mice, there was no significant difference in lung neutrophil apoptosis or neutrophil entry into the lung after hemorrhage or endotoxemia compared to wild-type mice. Our results show that apoptosis among lung neutrophils is decreased for more than 24 h after hemorrhage or endotoxemia. Although IL-1beta expression is increased in lung neutrophils under these conditions, IL-1beta is not responsible for either the influx of neutrophils into the lung or the reduction of apoptosis in neutrophil populations after hemorrhage or endotoxemia.

  14. The effect of lipocortin 1 on neutrophil deformability

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    E. M. Drost

    1996-01-01

    Full Text Available Lipocortn 1 (Lc1 is an anti-inflammatory protein, which, given systemically, inhibits polymorphonuclear neutrophil (PMN emigration from the circulation to sites of inflammation; delivery of Lc1 to the inflamed site is ineffective. We have examined the effect of Lc1 on changes in PMN deformability, and observed a consistent improvement in the deformability of unstimulated PMN; N-formyl-methionyl-leucyl-phenylalanine (fMLP-activated cell deformability was unaltered. A Lc1-induced increase in cell deformability may reduce PMN sequestration so contributing to the anti-migratory effects of systemic Lc1 previously demonstrated in vivo.

  15. Circulating immunoglobulins are not associated with intraplaque mast cell number and other vulnerable plaque characteristics in patients with carotid artery stenosis.

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    Sanne Willems

    Full Text Available BACKGROUND: Recently, we have shown that intraplaque mast cell numbers are associated with atherosclerotic plaque vulnerability and with future cardiovascular events, which renders inhibition of mast cell activation of interest for future therapeutic interventions. However, the endogenous triggers that activate mast cells during the progression and destabilization of atherosclerotic lesions remain unidentified. Mast cells can be activated by immunoglobulins and in the present study, we aimed to establish whether specific immunoglobulins in plasma of patients scheduled for carotid endarterectomy were related to (activated intraplaque mast cell numbers and plasma tryptase levels. In addition, the levels were related to other vulnerable plaque characteristics and baseline clinical data. METHODS AND RESULTS: OxLDL-IgG, total IgG and total IgE levels were measured in 135 patients who underwent carotid endarterectomy. No associations were observed between the tested plasma immunoglobulin levels and total mast cell numbers in atherosclerotic plaques. Furthermore, no associations were found between IgG levels and the following plaque characteristics: lipid core size, degree of calcification, number of macrophages or smooth muscle cells, amount of collagen and number of microvessels. Interestingly, statin use was negatively associated with plasma IgE and oxLDL-IgG levels. CONCLUSIONS: In patients suffering from carotid artery disease, total IgE, total IgG and oxLDL-IgG levels do not associate with plaque mast cell numbers or other vulnerable plaque histopathological characteristics. This study thus does not provide evidence that the immunoglobulins tested in our cohort play a role in intraplaque mast cell activation or grade of atherosclerosis.

  16. Ageing exacerbates damage of systemic and salivary neutrophils from patients presenting Candida-related denture stomatitis

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    Porto Vinicius

    2009-03-01

    Full Text Available Abstract Background Ageing leads to a decline in the function of the immune system, increasing the body's susceptibility to infections through the impairment of T-cells, macrophages, neutrophils and dendritic cells Denture stomatitis is a primary oral disease affecting elderly denture wearers. The major etiologic factor involved in this pathology is the infection by Candida albicans, an opportunistic pathogen that causes local and disseminated diseases in immunosuppressed humans. Neutrophils play a critical role in the immune response against C. albicans and are continually present in the salivary fluid and in the blood. The aim of this study was to determine ageing-related changes in salivary and blood neutrophils and their potential implications in Candida-related denture stomatitis. Results Our results showed a lower number of neutrophils in the saliva from patients presenting Candida-related denture stomatitis in comparison to their matched controls. Furthermore, fewer neutrophils were isolated from the saliva of aged control individuals in comparison to matched younger subjects. CXCR1, CD62L and CD11b expression were significantly greater on systemic neutrophils from younger control individuals. Elderly individuals showed more apoptotic salivary neutrophils and lower GM-CSF levels than younger ones, regardless of the occurrence of Candida infection. On the other hand, CXCL-8 concentrations were higher in the saliva from elderly individuals. Besides, TNF-α was detected at elevated levels in the saliva from infected elderly subjects. Salivary neutrophils from elderly and young patients presented impaired phagocytic activity against C. albicans. However, just systemic neutrophils from elderly showed decreased phagocytosis when compared to the younger ones, regardless of the occurrence of infection. In addition, neutrophils from aged individuals and young patients presented low fungicidal activity. Conclusion The data suggests that the Candida

  17. Mechanisms of interferon-γ production by neutrophils and its function during Streptococcus pneumoniae pneumonia.

    Science.gov (United States)

    Gomez, John C; Yamada, Mitsuhiro; Martin, Jessica R; Dang, Hong; Brickey, W June; Bergmeier, Wolfgang; Dinauer, Mary C; Doerschuk, Claire M

    2015-03-01

    Bacterial pneumonia is a common public health problem associated with significant mortality, morbidity, and cost. Neutrophils are usually the earliest leukocytes to respond to bacteria in the lungs. Neutrophils rapidly sequester in the pulmonary microvasculature and migrate into the lung parenchyma and alveolar spaces, where they perform numerous effector functions for host defense. Previous studies showed that migrated neutrophils produce IFN-γ early during pneumonia induced by Streptococcus pneumoniae and that early production of IFN-γ regulates bacterial clearance. IFN-γ production by neutrophils requires Rac2, Hck/Lyn/Fgr Src family tyrosine kinases, and NADPH oxidase. Our current studies examined the mechanisms that regulate IFN-γ production by lung neutrophils during acute S. pneumoniae pneumonia in mice and its function. We demonstrate that IFN-γ production by neutrophils is a tightly regulated process that does not require IL-12. The adaptor molecule MyD88 is critical for IFN-γ production by neutrophils. The guanine nucleotide exchange factor CalDAG-GEFI modulates IFN-γ production. The CD11/CD18 complex, CD44, Toll-like receptors 2 and 4, TRIF, and Nrf2 are not required for IFN-γ production by neutrophils. The recently described neutrophil-dendritic cell hybrid cell, identified by its expression of Ly6G and CD11c, is present at low numbers in pneumonic lungs and is not a source of IFN-γ. IFN-γ produced by neutrophils early during acute S. pneumoniae pneumonia induces transcription of target genes in the lungs, which are critical for host defense. These studies underline the complexity of the neutrophil responses during pneumonia in the acute inflammatory response and in subsequent resolution or initiation of immune responses.

  18. Type I interferon transcriptional signature in neutrophils and high frequency of low-density granulocytes are associated with tissue damage in malaria

    Science.gov (United States)

    Rocha, Bruno Coelho; Marques, Pedro Elias; Leoratti, Fabiana Maria de Souza; Junqueira, Caroline; Pereira, Dhelio Batista; Antonelli, Lis Ribeiro do Valle; Menezes, Gustavo Batista

    2015-01-01

    SUMMARY Neutrophils are the most abundant leukocyte population in the bloodstream, the primary compartment of Plasmodium sp. infection. Yet, the role of these polymorphonuclear cells in mediating either resistance or pathogenesis of malaria is poorly understood. We report that circulating neutrophils from malaria patients are highly activated, as indicated by a strong type I interferon transcriptional signature, increased expression of surface activation markers, the enhanced release of reactive oxygen species and myeloperoxidase, as well as the high frequency of low-density granulocytes. The activation of neutrophils was associated with increased levels of serum alanine and aspartate aminotransferases, indicating liver damage. In a rodent malaria model, we observed an intense recruitment of neutrophils to liver sinusoids. Neutrophil migration, IL-1β and chemokine expression as well as liver damage were all dependent on type I interferon signaling. The data suggests that type I interferon signaling have a central role in neutrophil activation and malaria pathogenesis. PMID:26711347

  19. Neutrophils and neutrophil serine proteases are increased in the spleens of estrogen-treated C57BL/6 mice and several strains of spontaneous lupus-prone mice

    Science.gov (United States)

    Dai, Rujuan; Cowan, Catharine; Heid, Bettina; Khan, Deena; Liang, Zhihong; Pham, Christine T. N.; Ahmed, S. Ansar

    2017-01-01

    Estrogen, a natural immunomodulator, regulates the development and function of diverse immune cell types. There is now renewed attention on neutrophils and neutrophil serine proteases (NSPs) such as neutrophil elastase (NE), proteinase 3 (PR3), and cathepsin G (CG) in inflammation and autoimmunity. In this study, we found that although estrogen treatment significantly reduced total splenocytes number, it markedly increased the splenic neutrophil absolute numbers in estrogen-treated C57BL/6 (B6) mice when compared to placebo controls. Concomitantly, the levels of NSPs and myeloperoxidase (MPO) were highly upregulated in the splenocytes from estrogen-treated mice. Despite the critical role of NSPs in the regulation of non-infectious inflammation, by employing NE-/-/PR3-/-/CG-/- triple knock out mice, we demonstrated that the absence of NSPs affected neither estrogen’s ability to increase splenic neutrophils nor the induction of inflammatory mediators (IFNγ, IL-1β, IL-6, TNFα, MCP-1, and NO) from ex vivo activated splenocytes. Depletion of neutrophils in vitro in splenocytes with anti-Ly6G antibody also had no obvious effect on NSP expression or LPS-induced IFNγ and MCP-1. These data suggest that estrogen augments NSPs, which appears to be independent of enhancing ex vivo inflammatory responses. Since estrogen has been implicated in regulating several experimental autoimmune diseases, we extended our observations in estrogen-treated B6 mice to spontaneous autoimmune-prone female MRL-lpr, B6-lpr and NZB/WF1 mice. There was a remarkable commonality with regards to the increase of neutrophils and concomitant increase of NSPs and MPO in the splenic cells of different strains of autoimmune-prone mice and estrogen-treated B6 mice. Collectively, since NSPs and neutrophils are involved in diverse pro-inflammatory activities, these data suggest a potential pathologic implication of increased neutrophils and NSPs that merits further investigation. PMID:28192517

  20. [Neutrophils and monocytes in gingival epithelium

    Science.gov (United States)

    Meng, H X; Zheng, L P

    1994-06-01

    Neutrophils and monocytes of gingival epithellium in health gingiva(H),marginal gingivitis(MG),juvenile periodontitis(JP),adult periodontitis(AP) and subgingival bacteria were quantitated and analyzed,The results showed that the numbers of PMN within either pocket epithelium or oral gingival epithelium in JP were significantly lower than in AP and G.The amounts of PMN in AP were much larger than other three groups.Positive correlation between the number of PMN in sulcular pocket epitelium and the motile bacteri of subgingival plaque was demonstrated by correlation analysis.Monocytes mainly presented in deep pocket and junctional epithelum which were stained by NAE method,however very few Langhans cells were seen in these areas.

  1. Metabolic regulation of neutrophil spreading, membrane tubulovesicular extensions (cytonemes) formation and intracellular pH upon adhesion to fibronectin.

    Science.gov (United States)

    Galkina, Svetlana I; Sud'ina, Galina F; Klein, Thomas

    2006-08-01

    Circulating leukocytes have a round cell shape and roll along vessel walls. However, metabolic disorders can lead them to adhere to the endothelium and spread (flatten). We studied the metabolic regulation of adhesion, spreading and intracellular pH (pHi) of neutrophils (polymorphonuclear leukocytes) upon adhesion to fibronectin-coated substrata. Resting neutrophils adhered and spread on fibronectin. An increase in pHi accompanied neutrophil spreading. Inhibition of oxidative phosphorylation or inhibition of P- and F-type ATPases affected neither neutrophil spreading nor pHi. Inhibition of glucose metabolism or V-ATPase impaired neutrophil spreading, blocked the increase in the pHi and induced extrusion of membrane tubulovesicular extensions (cytonemes), anchoring cells to substrata. Omission of extracellular Na(+) and inhibition of chloride channels caused a similar effect. We propose that these tubulovesicular extensions represent protrusions of exocytotic trafficking, supplying the plasma membrane of neutrophils with ion exchange mechanisms and additional membrane for spreading. Glucose metabolism and V-type ATPase could affect fusion of exocytotic trafficking with the plasma membrane, thus controlling neutrophil adhesive state and pHi. Cl(-) efflux through chloride channels and Na(+) influx seem to be involved in the regulation of the V-ATPase by carrying out charge compensation for the proton-pumping activity and through V-ATPase in regulation of neutrophil spreading and pHi.

  2. Real-time in vivo imaging reveals the ability of neutrophils to remove Cryptococcus neoformans directly from the brain vasculature.

    Science.gov (United States)

    Zhang, Mingshun; Sun, Donglei; Liu, Gongguan; Wu, Hui; Zhou, Hong; Shi, Meiqing

    2016-03-01

    Although neutrophils are typically the first immune cells attracted to an infection site, little is known about how neutrophils dynamically interact with invading pathogens in vivo. Here, with the use of intravital microscopy, we demonstrate that neutrophils migrate to the arrested Cryptococcus neoformans, a leading agent to cause meningoencephalitis, in the brain microvasculature. Following interactions with C. neoformans, neutrophils were seen to internalize the organism and then circulate back into the bloodstream, resulting in a direct removal of the organism from the endothelial surface before its transmigration into the brain parenchyma. C. neoformans infection led to enhanced expression of adhesion molecules macrophage 1 antigen on neutrophils and ICAM-1 on brain endothelial cells. Depletion of neutrophils enhanced the brain fungal burden. Complement C3 was critically involved in the recognition of C. neoformans by neutrophils and subsequent clearance of the organism from the brain. Together, our finding of the direct removal of C. neoformans by neutrophils from its arrested site may represent a novel mechanism of host defense in the brain, in addition to the known, direct killing of microorganisms at the infection sites. These data are the first to characterize directly the dynamic interactions of leukocytes with a microbe in the brain of a living animal.

  3. Global analysis of neutrophil responses to Neisseria gonorrhoeae reveals a self-propagating inflammatory program.

    Directory of Open Access Journals (Sweden)

    Anna Sintsova

    2014-09-01

    Full Text Available An overwhelming neutrophil-driven response causes both acute symptoms and the lasting sequelae that result from infection with Neisseria gonorrhoeae. Neutrophils undergo an aggressive opsonin-independent response to N. gonorrhoeae, driven by the innate decoy receptor CEACAM3. CEACAM3 is exclusively expressed by human neutrophils, and drives a potent binding, phagocytic engulfment and oxidative killing of Opa-expressing bacteria. In this study, we sought to explore the contribution of neutrophils to the pathogenic inflammatory process that typifies gonorrhea. Genome-wide microarray and biochemical profiling of gonococcal-infected neutrophils revealed that CEACAM3 engagement triggers a Syk-, PKCδ- and Tak1-dependent signaling cascade that results in the activation of an NF-κB-dependent transcriptional response, with consequent production of pro-inflammatory cytokines. Using an in vivo model of N. gonorrhoeae infection, we show that human CEACAM-expressing neutrophils have heightened migration toward the site of the infection where they may be further activated upon Opa-dependent binding. Together, this study establishes that the role of CEACAM3 is not restricted to the direct opsonin-independent killing by neutrophils, since it also drives the vigorous inflammatory response that typifies gonorrhea. By carrying the potential to mobilize increasing numbers of neutrophils, CEACAM3 thereby represents the tipping point between protective and pathogenic outcomes of N. gonorrhoeae infection.

  4. The effect of free and carrier-bound cortisol on equine neutrophil function.

    Science.gov (United States)

    Fratto, Melanie A; Hart, Kelsey A; Norton, Natalie A; Barton, Michelle H; Giguère, Steeve; Hurley, David J

    2017-01-01

    Cortisol is a key anti-inflammatory hormone that increases in bacterial sepsis and circulates predominantly bound to cortisol binding globulin (CBG). Only unbound cortisol was believed to be biologically active, but recent evidence suggests that CBG-bound cortisol also regulates inflammation. The objective of this study was to evaluate the effects of free and CBG-bound cortisol on equine neutrophil function ex vivo. We hypothesized that CBG would enhance cortisol-mediated suppression of neutrophil pro-inflammatory responses. Neutrophils isolated from 8 foals and 6 adult horses were exposed to Staphylococcus aureus antigen (SAA) alone and with hydrocortisone (HC), CBG, or both (CBG+HC). Inflammatory cytokine (TNF-α, IL-8) and reactive oxygen species (ROS) production were measured and compared among stimulants and between ages with linear mixed-effects models. CBG and CBG+HC inhibited ROS production induced by SAA in both foal and horse neutrophils, maintaining it at levels comparable to baseline production (P≤0.060-0.907). TNF-α production was not significantly different among stimulants (P=0.284). CBG+HC significantly (P≤0.016) increased IL-8 production by neutrophils in response to SAA in both foals and adults, although the response of foals was significantly greater than that of adults (P<0.001). These findings suggest that CBG directly modulates equine neutrophil responses, but the effects are cytokine- and age-specific.

  5. Toll-like receptors elicit different recruitment kinetics of monocytes and neutrophils in mouse acute inflammation.

    Science.gov (United States)

    Imhof, Beat A; Jemelin, Stephane; Emre, Yalin

    2017-03-16

    Leukocyte recruitment is an important process in combatting pathogens. The largest class of circulating leukocytes are neutrophils, which rapidly invade inflamed tissue, followed by inflammatory Ly6C(+) monocytes. Ly6C(low) monocytes patrol the endothelial wall routinely in the steady state. We recently reported early luminal recruitment of Ly6C(low) monocytes, which preceded and orchestrated neutrophil arrival and extravasation in response to TLR7/8-mediated vascular inflammation. Here we dissected the kinetics of recruitment of monocytes and neutrophils and examined the dynamics of Ly6C(low) monocytes in response to several other Toll-like receptor (TLR) agonists, using intravital confocal microscopy. We observed two types of kinetics in mesenteric veins. TLR2, TLR5 and TLR9 agonists caused early monocyte and neutrophil influx whereas TLR3 and TLR4 agonists rapidly recruited neutrophils and caused Ly6C(low) monocytes to arrive at low levels later on. All TLR agonists, except TLR9, led Ly6C(low) monocytes to meticulously patrol the vascular wall. Finally, these monocytes released pro-inflammatory cytokines and chemokines implicated in neutrophil recruitment in response to TLR2, TLR4 and TLR9 stimulation but not to TLR3 and TLR5 agonists. These results refine our understanding of the early events in the leukocyte recruitment cascade, including the patrolling behaviour of Ly6C(low) monocytes, in TLR-mediated acute vascular inflammation. This article is protected by copyright. All rights reserved.

  6. Effect of neutrophil depletion on gelatinase expression, edema formation and hemorrhagic transformation after focal ischemic stroke

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    Machado Livia S

    2005-08-01

    Full Text Available Abstract Background While gelatinase (MMP-2 and -9 activity is increased after focal ischemia/reperfusion injury in the brain, the relative contribution of neutrophils to the MMP activity and to the development of hemorrhagic transformation remains unknown. Results Anti-PMN treatment caused successful depletion of neutrophils in treated animals. There was no difference in either infarct volume or hemorrhage between control and PMN depleted animals. While there were significant increases in gelatinase (MMP-2 and MMP-9 expression and activity and edema formation associated with ischemia, neutrophil depletion failed to cause any change. Conclusion The main finding of this study is that, in the absence of circulating neutrophils, MMP-2 and MMP-9 expression and activity are still up-regulated following focal cerebral ischemia. Additionally, neutrophil depletion had no influence on indicators of ischemic brain damage including edema, hemorrhage, and infarct size. These findings indicate that, at least acutely, neutrophils are not a significant contributor of gelatinase activity associated with acute neurovascular damage after stroke.

  7. Treatment with selectin blocking antibodies after lengthening contractions of mouse muscle blunts neutrophil accumulation but does not reduce damage.

    Science.gov (United States)

    Sloboda, Darcée D; Brooks, Susan V

    2016-01-01

    P- and E-selectins are expressed on the surface of endothelial cells and may contribute to neutrophil recruitment following injurious lengthening contractions of skeletal muscle. Blunting neutrophil, but not macrophage, accumulation after lengthening contractions may provide a therapeutic benefit as neutrophils exacerbate damage to muscle fibers, while macrophages promote repair. In this study, we tested the hypothesis that P- and E-selectins contribute to neutrophil, but not macrophage, accumulation in muscles after contraction-induced injury, and that reducing neutrophil accumulation by blocking the selectins would be sufficient to reduce damage to muscle fibers. To test our hypothesis, we treated mice with antibodies to block P- and E-selectin function and assessed leukocyte accumulation and damage in muscles 2 days after lengthening contractions. Treatment with P/E-selectin blocking antibodies reduced neutrophil content by about half in muscles subjected to lengthening contractions. In spite of the reduction in neutrophil accumulation, we did not detect a decrease in damage 2 days after lengthening contractions. We conclude that P- and/or E-selectin contribute to the neutrophil accumulation associated with contraction-induced muscle damage and that only a portion of the neutrophils that typically accumulate following injurious lengthening contractions is sufficient to induce muscle fiber damage and force deficits. Thus, therapeutic interventions based on blocking the selectins or other adhesion proteins will have to reduce neutrophil numbers by more than 50% in order to provide a benefit.

  8. Antimyeloperoxidase antibodies rapidly induce alpha-4-integrin-dependent glomerular neutrophil adhesion.

    Science.gov (United States)

    Kuligowski, Michael P; Kwan, Rain Y Q; Lo, Cecilia; Wong, Cyndi; James, Will G; Bourges, Dorothee; Ooi, Joshua D; Abeynaike, Latasha D; Hall, Pam; Kitching, A Richard; Hickey, Michael J

    2009-06-18

    Patients with antineutrophil cytoplasmic antibodies (ANCAs) frequently develop severe vasculitis and glomerulonephritis. Although ANCAs, particularly antimyeloperoxidase (anti-MPO), have been shown to promote leukocyte adhesion in postcapillary venules, their ability to promote adhesion in the glomerular vasculature is less clear. We used intravital microscopy to examine glomerular leukocyte adhesion induced by anti-MPO. In mice pretreated with LPS, 50 microg anti-MPO induced LFA-1-dependent adhesion in glomeruli. In concert with this finding, in mice pretreated with LPS, more than 80% of circulating neutrophils bound anti-MPO within 5 minutes of intravenous administration. However, even in the absence of LPS, more than 40% of circulating neutrophils bound anti-MPO in vivo, a response not seen in MPO(-/-) mice. In addition, a higher dose of anti-MPO (200 microg) induced robust glomerular leukocyte adhesion in the absence of LPS. The latter response was beta2-integrin independent, instead requiring the alpha4-integrin, which was up-regulated on neutrophils in response to anti-MPO. These data indicate that anti-MPO antibodies bind to circulating neutrophils, and can induce glomerular leukocyte adhesion via multiple pathways. Lower doses induce adhesion only after an infection-related stimulus, whereas higher doses are capable of inducing responses in the absence of an additional inflammatory stimulus, via alternative adhesion mechanisms.

  9. Increased Nucleosomes and Neutrophil Activation Link to Disease Progression in Patients with Scrub Typhus but Not Murine Typhus in Laos.

    Science.gov (United States)

    Paris, Daniel H; Stephan, Femke; Bulder, Ingrid; Wouters, Diana; van der Poll, Tom; Newton, Paul N; Day, Nicholas P J; Zeerleder, Sacha

    2015-01-01

    Cell-mediated immunity is essential in protection against rickettsial illnesses, but the role of neutrophils in these intracellular vasculotropic infections remains unclear. This study analyzed the plasma levels of nucleosomes, FSAP-activation (nucleosome-releasing factor), and neutrophil activation, as evidenced by neutrophil-elastase (ELA) complexes, in sympatric Lao patients with scrub typhus and murine typhus. In acute scrub typhus elevated nucleosome levels correlated with lower GCS scores, raised respiratory rate, jaundice and impaired liver function, whereas neutrophil activation correlated with fibrinolysis and high IL-8 plasma levels, a recently identified predictor of severe disease and mortality. Nucleosome and ELA complex levels were associated with a 4.8-fold and 4-fold increased risk of developing severe scrub typhus, beyond cut off values of 1,040 U/ml for nucleosomes and 275 U/ml for ELA complexes respectively. In murine typhus, nucleosome levels associated with pro-inflammatory cytokines and the duration of illness, while ELA complexes correlated strongly with inflammation markers, jaundice and increased respiratory rates. This study found strong correlations between circulating nucleosomes and neutrophil activation in patients with scrub typhus, but not murine typhus, providing indirect evidence that nucleosomes could originate from neutrophil extracellular trap (NET) degradation. High circulating plasma nucleosomes and ELA complexes represent independent risk factors for developing severe complications in scrub typhus. As nucleosomes and histones exposed on NETs are highly cytotoxic to endothelial cells and are strongly pro-coagulant, neutrophil-derived nucleosomes could contribute to vascular damage, the pro-coagulant state and exacerbation of disease in scrub typhus, thus indicating a detrimental role of neutrophil activation. The data suggest that increased neutrophil activation relates to disease progression and severe complications, and

  10. Simvastatin antagonizes CD40L secretion, CXC chemokine formation, and pulmonary infiltration of neutrophils in abdominal sepsis.

    Science.gov (United States)

    Zhang, Su; Rahman, Milladur; Zhang, Songen; Qi, Zhongquan; Thorlacius, Henrik

    2011-05-01

    Statins have been reported to exert anti-inflammatory actions and protect against septic organ dysfunction. Herein, we hypothesized that simvastatin may attenuate neutrophil activation and lung damage in abdominal sepsis. Male C57BL/6 mice were pretreated with simvastatin (0.5 or 10 mg/kg) before CLP. In separate groups, mice received an anti-CD40L antibody or a CXCR2 antagonist (SB225002) prior to CLP. BALF and lung tissue were harvested for analysis of neutrophil infiltration, as well as edema and CXC chemokine formation. Blood was collected for analysis of Mac-1 and CD40L expression on neutrophils and platelets, as well as soluble CD40L in plasma. Simvastatin decreased CLP-induced neutrophil infiltration and edema formation in the lung. Moreover, Mac-1 expression increased on septic neutrophils, which was significantly attenuated by simvastatin. Inhibition of CD40L reduced CLP-induced up-regulation of Mac-1 on neutrophils. Simvastatin prevented CD40L shedding from the surface of platelets and reduced circulating levels of CD40L in septic mice. CXC chemokine-induced migration of neutrophils in vitro was decreased greatly by simvastatin. Moreover, simvastatin abolished CLP-evoked formation of CXC chemokines in the lung, and a CXCR2 antagonist attenuated pulmonary accumulation of neutrophils. Our data suggest that the inhibitory effect of simvastatin on pulmonary accumulation of neutrophils may be related to a reduction of CD40L secretion into the circulation, as well as a decrease in CXC chemokine formation in the lung. Thus, these protective mechanisms help to explain the beneficial actions exerted by statins, such as simvastatin, in sepsis.

  11. Tracking neutrophil intraluminal crawling, transendothelial migration and chemotaxis in tissue by intravital video microscopy.

    Science.gov (United States)

    Xu, Najia; Lei, Xi; Liu, Lixin

    2011-09-24

    The recruitment of circulating leukocytes from blood stream to the inflamed tissue is a crucial and complex process of inflammation(1,2). In the postcapillary venules of inflamed tissue, leukocytes initially tether and roll on the luminal surface of venular wall. Rolling leukocytes arrest on endothelium and undergo firm adhesion in response to chemokine or other chemoattractants on the venular surface. Many adherent leukocytes relocate from the initial site of adhesion to the junctional extravasation site in endothelium, a process termed intraluminal crawling(3). Following crawling, leukocytes move across endothelium (transmigration) and migrate in extravascular tissue toward the source of chemoattractant (chemotaxis)(4). Intravital microscopy is a powerful tool for visualizing leukocyte-endothelial cell interactions in vivo and revealing cellular and molecular mechanisms of leukocyte recruitment(2,5). In this report, we provide a comprehensive description of using brightfield intravital microscopy to visualize and determine the detailed processes of neutrophil recruitment in mouse cremaster muscle in response to the gradient of a neutrophil chemoattractant. To induce neutrophil recruitment, a small piece of agarose gel (~1-mm(3) size) containing neutrophil chemoattractant MIP-2 (CXCL2, a CXC chemokine) or WKYMVm (Trp-Lys-Tyr-Val-D-Met, a synthetic analog of bacterial peptide) is placed on the muscle tissue adjacent to the observed postcapillary venule. With time-lapsed video photography and computer software ImageJ, neutrophil intraluminal crawling on endothelium, neutrophil transendothelial migration and the migration and chemotaxis in tissue are visualized and tracked. This protocol allows reliable and quantitative analysis of many neutrophil recruitment parameters such as intraluminal crawling velocity, transmigration time, detachment time, migration velocity, chemotaxis velocity and chemotaxis index in tissue. We demonstrate that using this protocol, these

  12. Effect of sevoflurane on human neutrophil apoptosis.

    LENUS (Irish Health Repository)

    Tyther, R

    2012-02-03

    BACKGROUND AND OBJECTIVE: Both chronic occupational exposure to volatile anaesthetic agents and acute in vitro exposure of neutrophils to isoflurane have been shown to inhibit the rate of apoptosis of human neutrophils. It is possible that inhibition of neutrophil apoptosis arises through delaying mitochondrial membrane potential collapse. We assessed mitochondrial depolarization and apoptosis in unexposed neutrophils and neutrophils exposed to sevoflurane in vivo. METHODS: A total of 20 mL venous blood was withdrawn pre- and postinduction of anaesthesia, the neutrophils isolated and maintained in culture. At 1, 12 and 24 h in culture, the percentage of neutrophil apoptosis was assessed by dual staining with annexin V-FITC and propidium iodide. Mitochondrial depolarization was measured using the dual emission styryl dye JC-1. RESULTS: Apoptosis was significantly inhibited in neutrophils exposed to sevoflurane in vivo at 24 (exposed: 38 (12)% versus control: 28 (11)%, P = 0.001), but not at 1 or 12 h, in culture. Mitochondrial depolarization was not delayed in neutrophils exposed to sevoflurane. CONCLUSIONS: The most important findings are that sevoflurane inhibits neutrophil apoptosis in vivo and that inhibition is not mediated primarily by an effect on mitochondrial depolarization.

  13. Endothelial domes encapsulate adherent neutrophils and minimize increases in vascular permeability in paracellular and transcellular emigration.

    Directory of Open Access Journals (Sweden)

    Mia Phillipson

    Full Text Available Local edema, a cardinal sign of inflammation associates closely with neutrophil emigration. Neutrophil emigration has been described to occur primarily through endothelial junctions (paracellular and more rarely directly through endothelial cells (transcellular. Recently, we reported that unlike in wild-type (wt mice, Mac-1-/- (CD11b neutrophils predominantly emigrated transcellularly and was significantly delayed taking 20-30 min longer than the paracellular emigration (wt. In the present study we noted significant anatomical disruption of the endothelium and hypothesized that transcellular emigration would greatly increase vascular permeability. Surprisingly, despite profound disruption of the endothelial barrier as the neutrophils moved through the cells, the changes in vascular permeability during transcellular emigration (Mac-1-/- were not increased more than in wt mice. Instead increased vascular permeability completely tracked the number of emigrated cells and as such, permeability changes were delayed in Mac-1-/- mice. However, by 60 min neutrophils from both sets of mice were emigrating in large numbers. Electron-microscopy and spinning disk multichannel fluorescence confocal microscopy revealed endothelial docking structures that progressed to dome-like structures completely covering wt and Mac-1-/- neutrophils. These domes completely enveloped the emigrating neutrophils in both wt and Mac-1-/- mice making the mode of emigration underneath these structures extraneous to barrier function. In conclusion, predominantly paracellular versus predominantly transcellular emigration does not affect vascular barrier integrity as endothelial dome-like structures retain barrier function.

  14. Endothelial domes encapsulate adherent neutrophils and minimize increases in vascular permeability in paracellular and transcellular emigration.

    Science.gov (United States)

    Phillipson, Mia; Kaur, Jaswinder; Colarusso, Pina; Ballantyne, Christie M; Kubes, Paul

    2008-02-20

    Local edema, a cardinal sign of inflammation associates closely with neutrophil emigration. Neutrophil emigration has been described to occur primarily through endothelial junctions (paracellular) and more rarely directly through endothelial cells (transcellular). Recently, we reported that unlike in wild-type (wt) mice, Mac-1-/- (CD11b) neutrophils predominantly emigrated transcellularly and was significantly delayed taking 20-30 min longer than the paracellular emigration (wt). In the present study we noted significant anatomical disruption of the endothelium and hypothesized that transcellular emigration would greatly increase vascular permeability. Surprisingly, despite profound disruption of the endothelial barrier as the neutrophils moved through the cells, the changes in vascular permeability during transcellular emigration (Mac-1-/-) were not increased more than in wt mice. Instead increased vascular permeability completely tracked the number of emigrated cells and as such, permeability changes were delayed in Mac-1-/- mice. However, by 60 min neutrophils from both sets of mice were emigrating in large numbers. Electron-microscopy and spinning disk multichannel fluorescence confocal microscopy revealed endothelial docking structures that progressed to dome-like structures completely covering wt and Mac-1-/- neutrophils. These domes completely enveloped the emigrating neutrophils in both wt and Mac-1-/- mice making the mode of emigration underneath these structures extraneous to barrier function. In conclusion, predominantly paracellular versus predominantly transcellular emigration does not affect vascular barrier integrity as endothelial dome-like structures retain barrier function.

  15. G Protein-Coupled Receptor 43 Modulates Neutrophil Recruitment during Acute Inflammation

    Science.gov (United States)

    Nicholls, Alyce J.; Oliveira, Ana Carolina; Mason, Linda J.; Binge, Lauren; Mackay, Charles R.; Wong, Connie H. Y.

    2016-01-01

    Fermentation of dietary fibre in the gut yields large amounts of short chain fatty acids (SCFAs). SCFAs can impart biological responses in cells through their engagement of ‘metabolite-sensing’ G protein-coupled receptors (GPCRs). One of the main SCFA receptors, GPR43, is highly expressed by neutrophils, which suggests that the actions of GPR43 and dietary fibre intake may affect neutrophil recruitment during inflammatory responses in vivo. Using intravital imaging of the small intestine, we found greater intravascular neutrophil rolling and adhesion in Gpr43−/−mice in response to LPS at 1 h. After 4 h of LPS challenge, the intravascular rolling velocity of GPR43-deficient neutrophils was reduced significantly and increased numbers of neutrophils were found in the lamina propria of Gpr43−/−mice. Additionally, GPR43-deficient leukocytes demonstrated exacerbated migration into the peritoneal cavity following fMLP challenge. The fMLP-induced neutrophil migration was significantly suppressed in wildtype mice that were treated with acetate, but not in Gpr43−/−mice, strongly suggesting a role for SCFAs in modulating neutrophil migration via GPR43. Indeed, neutrophils of no fibre-fed wildtype mice exhibited elevated migratory behaviour compared to normal chow-fed wildtype mice. Interestingly, this elevated migration could also be reproduced through simple transfer of a no fibre microbiota into germ-free mice, suggesting that the composition and function of microbiota stemming from a no fibre diet mediated the changes in neutrophil migration. Therefore, GPR43 and a microbiota composition that allows for SCFA production function to modulate neutrophil recruitment during inflammatory responses. PMID:27658303

  16. Vitamin C: A Novel Regulator of Neutrophil Extracellular Trap Formation

    Directory of Open Access Journals (Sweden)

    Ramesh Natarajan

    2013-08-01

    Full Text Available Introduction: Neutrophil extracellular trap (NET formation was recently identified as a novel mechanism to kill pathogens. However, excessive NET formation in sepsis can injure host tissues. We have recently shown that parenteral vitamin C (VitC is protective in sepsis. Whether VitC alters NETosis is unknown. Methods: We used Gulo−/− mice as they lack the ability to synthesize VitC. Sepsis was induced by intraperitoneal infusion of a fecal stem solution (abdominal peritonitis, FIP. Some VitC deficient Gulo−/− mice received an infusion of ascorbic acid (AscA, 200 mg/kg 30 min after induction of FIP. NETosis was assessed histologically and by quantification for circulating free DNA (cf-DNA in serum. Autophagy, histone citrullination, endoplasmic reticulum (ER stress, NFκB activation and apoptosis were investigated in peritoneal PMNs. Results: Sepsis produced significant NETs in the lungs of VitC deficient Gulo−/− mice and increased circulating cf-DNA. This was attenuated in the VitC sufficient Gulo−/− mice and in VitC deficient Gulo−/− mice infused with AscA. Polymorphonuclear neutrophils (PMNs from VitC deficient Gulo−/− mice demonstrated increased activation of ER stress, autophagy, histone citrullination, and NFκB activation, while apoptosis was inhibited. VitC also significantly attenuated PMA induced NETosis in PMNs from healthy human volunteers.

  17. Relationship between T-SPOT.TB responses and numbers of circulating CD4+ T-cells in HIV infected patients with active tuberculosis.

    Science.gov (United States)

    Cai, Rentian; Chen, Jun; Guan, Liqian; Sun, Meiyan; Sun, Yang; Shen, Yinzhong; Zhang, Renfang; Liu, Li; Lu, Hongzhou

    2014-06-01

    This study sought to evaluate the performance of the T-SPOT.TB assay for the diagnosis of active tuberculosis (TB) in human immunodeficiency virus (HIV) infected patients. One hundred confirmed HIV-infected patients with active TB and known T-SPOT.TB and CD4+ T-cell counts were enrolled in this clinical retrospective study. We found that patients with lower CD4+ T-cell counts (11-50 cells/μL) had the lowest T-SPOT.TB positive rates (50%), and patients with higher CD4+ T-cell counts (50-100 cells/μL) had the highest T-SPOT.TB positive rates (75%). However, there were no significant differences between the T-SPOT.TB positive rates of patients with different CD4+ T-cell counts ( 100 cells/μL) (χ(2) = 3.7747, p = 0.287). The patients with positive TB culture results had significantly higher T-SPOT.TB positive rates (78.9%) than patients that were culture-negative (44.3%) (χ(2) = 12.8303, p SPOT.TB positive rates. The number of spot-forming cells (SFCs) reactive with ESAT-6, CFP-10 and ESAT-6/CFP-10-specific T cells detected by T-SPOT.TB were positively is strongly related to the degree of immunodeficiency, while the T-SPOT.TB positive rates are less dependent on the level of CD4+ T-cell depletion in HIV infection and active TB.

  18. Plasma sE-selectin level is positively correlated with neutrophil count and diastolic blood pressure in Japanese men.

    Science.gov (United States)

    Mochizuki, Kazuki; Inoue, Seiya; Miyauchi, Rie; Misaki, Yasumi; Shimada, Masaya; Kasezawa, Nobuhiko; Tohyama, Kazushige; Goda, Toshinao

    2013-01-01

    Increased levels of circulating soluble type of E-selectin (sE-selectin), neutrophil counts and blood pressure are associated with the development of cardiovascular diseases (CVD). In this study, we conducted a cross-sectional study of men who participated in health check-ups, and selected those who were not diagnosed with or being treated for metabolic diseases such as diabetes, hypertension and lipid abnormality according to the health check-ups. We measured their basic clinical parameters including blood pressure and neutrophil count, plasma sE-selectin concentration and lifestyle factors, and assessed their interrelations by multivariate linear regression (MLR) analysis. A total of 351 subjects aged 47.5±8.41 (range, 30-64) y were recruited. Significantly correlated with sE-selectin concentration were neutrophil count, diastolic blood pressure (DBP), and systolic blood pressure (SBP) (Pearson's correlation coefficient, 0.194, 0.220 and 0.175, respectively). MLR analysis showed that sE-selectin concentration was independently positively related with DBP and neutrophil count, whereas neutrophil count was positively associated with sE-selectin concentration but not DBP. DBP, but not SBP, was independently positively correlated with sE-selectin concentration but not neutrophil count. These results indicate that circulating sE-selectin concentration may be a biomarker for indicating subsequent development of metabolic diseases, in particular CVD, from a healthy state.

  19. Neutrophil Reverse Migration Becomes Transparent with Zebrafish

    Directory of Open Access Journals (Sweden)

    Taylor W. Starnes

    2012-01-01

    Full Text Available The precise control of neutrophil-mediated inflammation is critical for both host defense and the prevention of immunopathology. In vivo imaging studies in zebrafish, and more recently in mice, have made the novel observation that neutrophils leave a site of inflammation through a process called neutrophil reverse migration. The application of advanced imaging techniques to the genetically tractable, optically transparent zebrafish larvae was critical for these advances. Still, the mechanisms underlying neutrophil reverse migration and its effects on the resolution or priming of immune responses remain unclear. Here, we review the current knowledge of neutrophil reverse migration, its potential roles in host immunity, and the live imaging tools that make zebrafish a valuable model for increasing our knowledge of neutrophil behavior in vivo.

  20. Enhancement by platelets of oxygen radical responses of human neutrophils

    Energy Technology Data Exchange (ETDEWEB)

    McCulloch, K.K.; Powell, J.; Johnson, K.J.; Ward, P.A.

    1986-03-01

    When human blood neutrophils were incubated with immune complexes (consisting of IgG antibody) in the presence of platelets, there was a 2 to 10 fold enhancement in the generation of O-/sub 2/ and H/sub 2/O/sub 2/. This enhancement phenomenon was proportional to the dose of immune complex added and the number of platelets present. The response was not agonist specific since similar enhancement also occurred with the following agonists: phorbol myristate acetate, opsonized zymosan particles and the chemotactic peptide N-formyl-met-leu-phe. The platelet related phenomenon of enhanced O-/sub 2/ generation could not be reproduced by the addition of serotonin, histamine or platelet-derived growth factor and was not affected by prior treatment of platelets with cyclooxygenase inhibitors (indomethacin, piroxicam) or lipoxygenase inhibitors (nafazatrom, BW755C or nordihydroguaiaretic acid). However, activation of platelets by thrombin caused release into the platelet supernatant fluid of a factor that, only in the presence of immune complexes, caused enhanced O-/sub 2/ responses to neutrophils. These data indicate that platelets potentiate oxygen radical responses of human neutrophils and suggest a mechanisms by which platelets may participate in tissue injury which is mediated by oxygen radical products from activated neutrophils.

  1. Cryptococcus Neoformans Modulates Extracellular Killing by Neutrophils

    OpenAIRE

    Qureshi, Asfia; Grey, Angus; Rose, Kristie L; Schey, Kevin L.; Del Poeta, Maurizio

    2011-01-01

    We recently established a key role for host sphingomyelin synthase (SMS) in regulating the killing activity of neutrophils against Cryptococcus neoformans. In this paper, we studied the effect of C. neoformans on the killing activity of neutrophils and whether SMS would still be a player against C. neoformans in immunocompromised mice lacking T and natural killer (NK) cells (Tgε26 mice). To this end, we analyzed whether C. neoformans would have any effect on neutrophil survival and killing in...

  2. Neutrophil Migration into the Infected Uroepithelium Is Regulated by the Crosstalk between Resident and Helper Macrophages

    Directory of Open Access Journals (Sweden)

    Kristina Zec

    2016-02-01

    Full Text Available The antibacterial defense against infections depends on the cooperation between distinct phagocytes of the innate immune system, namely macrophages and neutrophils. However, the mechanisms driving this cooperation are incompletely understood. In this study we describe the crosstalk between Ly6C+ and Ly6C− macrophage-subtypes and neutrophils in the context of urinary tract infection (UTI with uropathogenic E. coli (UPEC. Ly6C− macrophages acted as tissue resident sentinels and attracted circulating phagocytes by chemokines. Ly6C+ macrophages produced tumor necrosis factor (TNF that licensed Ly6C− macrophages to release preformed CXCL2, which in turn caused matrix metalloproteinases (MMP-9 secretion by neutrophils to enable transepithelial migration.

  3. Bordetella parapertussis Circumvents Neutrophil Extracellular Bactericidal Mechanisms

    Science.gov (United States)

    Gorgojo, Juan; Scharrig, Emilia; Gómez, Ricardo M.; Harvill, Eric T.; Rodríguez, Maria Eugenia

    2017-01-01

    B. parapertussis is a whooping cough etiological agent with the ability to evade the immune response induced by pertussis vaccines. We previously demonstrated that in the absence of opsonic antibodies B. parapertussis hampers phagocytosis by neutrophils and macrophages and, when phagocytosed, blocks intracellular killing by interfering with phagolysosomal fusion. But neutrophils can kill and/or immobilize extracellular bacteria through non-phagocytic mechanisms such as degranulation and neutrophil extracellular traps (NETs). In this study we demonstrated that B. parapertussis also has the ability to circumvent these two neutrophil extracellular bactericidal activities. The lack of neutrophil degranulation was found dependent on the O antigen that targets the bacteria to cell lipid rafts, eventually avoiding the fusion of nascent phagosomes with specific and azurophilic granules. IgG opsonization overcame this inhibition of neutrophil degranulation. We further observed that B. parapertussis did not induce NETs release in resting neutrophils and inhibited NETs formation in response to phorbol myristate acetate (PMA) stimulation by a mechanism dependent on adenylate cyclase toxin (CyaA)-mediated inhibition of reactive oxygen species (ROS) generation. Thus, B. parapertussis modulates neutrophil bactericidal activity through two different mechanisms, one related to the lack of proper NETs-inducer stimuli and the other one related to an active inhibitory mechanism. Together with previous results these data suggest that B. parapertussis has the ability to subvert the main neutrophil bactericidal functions, inhibiting efficient clearance in non-immune hosts. PMID:28095485

  4. Fungal and bacterial killing by neutrophils.

    Science.gov (United States)

    Ermert, David; Zychlinsky, Arturo; Urban, Constantin

    2009-01-01

    Neutrophils are professional phagocytes of the innate immune system that are essential to control bacterial and fungal infections. These cells engulf and kill invading microbes. Additionally, activated neutrophils are able to release neutrophil extracellular traps (NETs). These fibers consist of chromatin decorated with antimicrobial proteins to trap and kill microbes. Appropriate quantitative methods are required to understand the nature of interactions of neutrophils with pathogens. Here we present assays to measure killing mediated by phagocytosis, by NETs, by a combination of both, and by granular extract. As examples, we use Candida albicans for fungal and Shigella flexneri for bacterial pathogens.

  5. CFTR targeting during activation of human neutrophils.

    Science.gov (United States)

    Ng, Hang Pong; Valentine, Vincent G; Wang, Guoshun

    2016-12-01

    Cystic fibrosis transmembrane conductance regulator (CFTR), a cAMP-activated chloride channel, plays critical roles in phagocytic host defense. However, how activated neutrophils regulate CFTR channel distribution subcellularly is not well defined. To investigate, we tested multiple Abs against different CFTR domains, to examine CFTR expression in human peripheral blood neutrophils by flow cytometry. The data confirmed that resting neutrophils had pronounced CFTR expression. Activation of neutrophils with soluble or particulate agonists did not significantly increase CFTR expression level, but induced CFTR redistribution to cell surface. Such CFTR mobilization correlated with cell-surface recruitment of formyl-peptide receptor during secretory vesicle exocytosis. Intriguingly, neutrophils from patients with ΔF508-CF, despite expression of the mutant CFTR, showed little cell-surface mobilization upon stimulation. Although normal neutrophils effectively targeted CFTR to their phagosomes, ΔF508-CF neutrophils had impairment in that process, resulting in deficient hypochlorous acid production. Taken together, activated neutrophils regulate CFTR distribution by targeting this chloride channel to the subcellular sites of activation, and ΔF508-CF neutrophils fail to achieve such targeting, thus undermining their host defense function.

  6. DNase expression allows the pathogen group A streptococcus to escape killing in neutrophil extracellular traps

    OpenAIRE

    Buchanan, John T; Simpson, Amelia J; Aziz, Ramy K.; Liu, George Y.; Kristian, Sascha A.; Kotb, Malak; Feramisco, James; Nizet, Victor

    2006-01-01

    The innate immune response plays a crucial role in satisfactory host resolution of bacterial infection. In response to chemotactic signals, neutrophils are early responding cells that migrate in large numbers to sites of infection. The recent discovery of secreted neutrophil extracellular traps (NETs) composed of DNA and histones opened a novel dimension in our understanding of the microbial killing capacity of these specialized leukocytes. M1 serotype strains of the pathogen Group A Streptoc...

  7. The effects of extracellular matrix proteins on neutrophil-endothelial interaction--a roadway to multiple therapeutic opportunities.

    Science.gov (United States)

    Padmanabhan, Jagannath; Gonzalez, Anjelica L

    2012-06-01

    Polymorphoneuclear leukocytes or neutrophils, a major component of white blood cells, contribute to the innate immune response in humans. Upon sensing changes in the microenvironment, neutrophils adhere to the vascular wall, migrate through the endothelial cell (EC)-pericyte bilayer, and subsequently through the extracellular matrix to reach the site of inflammation. These cells are capable of destroying microbes, cell debris, and foreign proteins by oxidative and non-oxidative processes. While primarily mediators of tissue homeostasis, there are an increasing number of studies indicating that neutrophil recruitment and transmigration can also lead to host-tissue injury and subsequently inflammation-related diseases. Neutrophil-induced tissue injury is highly regulated by the microenvironment of the infiltrated tissue, which includes cytokines, chemokines, and the provisional extracellular matrix, remodeled through increased vascular permeability and other cellular infiltrates. Thus, investigation of the effects of matrix proteins on neutrophil-EC interaction and neutrophil transmigration may help identify the proteins that induce pro- or anti-inflammatory responses. This area of research presents an opportunity to identify therapeutic targets in inflammation-related diseases. This review will summarize recent literature on the role of neutrophils and the effects of matrix proteins on neutrophil-EC interactions, with focus on three different disease models: 1) atherosclerosis, 2) COPD, and 3) tumor growth and progression. For each disease model, inflammatory molecules released by neutrophils, important regulatory matrix proteins, current anti-inflammatory treatments, and the scope for further research will be summarized.

  8. Surface expression of HSP72 by LPS-stimulated neutrophils facilitates gammadeltaT cell-mediated killing.

    Science.gov (United States)

    Hirsh, Mark I; Hashiguchi, Naoyuki; Chen, Yu; Yip, Linda; Junger, Wolfgang G

    2006-03-01

    During inflammation and sepsis, accumulation of activated neutrophils causes lung tissue damage and organ failure. Effective clearance of neutrophils reduces the risk of organ failure; however, its mechanisms are poorly understood. Because lungs are rich in gammadeltaT cells, we investigated the physiological role of these cells in the protection of lung tissue from infiltrating neutrophils. In a mouse model of sepsis, we found that the lungs of survivors contained significantly higher numbers of gammadeltaT cells than those of mice that died from sepsis. The number of gammadeltaT cells correlated inversely with the number of neutrophils in the lungs and with the degree of lung tissue damage. LPS rapidly elicited the expression of heat shock protein (HSP) 72 on the surface of human neutrophils. Inhibitors of transcription, protein synthesis, and intracellular protein transport blocked HSP72 expression, indicating that de novo synthesis is required. gammadeltaT cells targeted and rapidly killed LPS-treated neutrophils through direct cell-to-cell contact. Pre-treatment with neutralizing antibodies to HSP72 diminished neutrophil killing. Our data indicate that HSP72 expression on the cell surface predisposes inflamed neutrophils to killing by gammadeltaT cells. This intercellular exchange may allow gammadeltaT cells to resolve inflammation and limit host tissue damage during sepsis.

  9. Neutrophil crawling in capillaries; a novel immune response to Staphylococcus aureus.

    Science.gov (United States)

    Harding, Mark Geoffrey; Zhang, Kunyan; Conly, John; Kubes, Paul

    2014-10-01

    Methicillin-resistant Staphylococcus aureus (MRSA), particularly the USA300 strain, is a highly virulent pathogen responsible for an increasing number of skin and soft tissue infections globally. Furthermore, MRSA-induced soft tissue infections can rapidly progress into life-threatening conditions, such as sepsis and necrotizing fasciitis. The importance of neutrophils in these devastating soft tissue infections remains ambiguous, partly because of our incomplete understanding of their behaviour. Spinning disk confocal microscopy was used to visualize the behaviour of GR1-labelled neutrophils in subcutaneous tissue in response to GFP-expressing MRSA attached to a foreign particle (agarose bead). We observed significant directional neutrophil recruitment towards the S. aureus agarose bead but not a control agarose bead. A significant increase in neutrophil crawling within the capillaries surrounding the infectious nidus was noted, with impaired capillary perfusion in these vessels and increased parenchymal cell death. No neutrophils were able to emigrate from capillaries. The crawling within these capillaries was mediated by the β(2) and α(4) integrins and blocking these integrins 2 hours post infection eliminated neutrophil crawling, improved capillary perfusion, reduced cell death and reduced lesion size. Blocking prior to infection increased pathology. Neutrophil crawling within capillaries during MRSA soft tissue infections, while potentially contributing to walling off or preventing early dissemination of the pathogen, resulted in impaired perfusion and increased tissue injury with time.

  10. Effects of copper-aspirin complex on platelet-neutrophil interactions

    Institute of Scientific and Technical Information of China (English)

    Zhi-qiang SHEN; Peng CHEN; Ling LI; Peng CHEN; Wei-ping LIU

    2004-01-01

    AIM: To investigate the effects of copper-aspirin complex on rat thrombosis and the interaction between platelets and neutrophils. METHODS: The model of electrically stimulated carotid artery thrombosis in Sprague Dawley rats was used; the effects of copper-aspirin complex on rat platelet-neutrophil adhesion and platelet aggregation stimulated by activated neutrophils were observed by rosette assay and Born's method, respectively. RESULTS:Intragastric copper-aspirin complex (5, 7, and 10 mg/kg) dose-dependently prolonged the occlusion time; it significantly decreased the rosette number formed between thrombin-activated platelets and neutrophils; the 50 % of inhibitory concentration (IC50) was (54.6±4.3) μmol/L. Copper-aspirin complex markedly inhibited rat platelet aggregation induced by either cell free supernatant of activated neutrophils or by activated neutrophil suspension.The values of IC50 were (224.5±16.2) μmol/L and (820.5±21.4) μmol/L, whereas aspirin had no influence.CONCLUSION: Copper-aspirin complex inhibited platelet-neutrophil interactions through a different property from aspirin and resulted in a more potent antithrombotic activity.

  11. Clozapine induces oxidative stress and proapoptotic gene expression in neutrophils of schizophrenic patients.

    Science.gov (United States)

    Fehsel, Karin; Loeffler, Stefan; Krieger, Klaus; Henning, Uwe; Agelink, Markus; Kolb-Bachofen, Victoria; Klimke, Ansgar

    2005-10-01

    The present study examined cellular effects of the atypical antipsychotic drug clozapine on blood cells of treated patients with and without clozapine-induced agranulocytosis (CA). Blood from one patient who commenced clozapine treatment was examined at weekly intervals for 128 days. Olanzapine-treated (n = 5) and polymedicated (n = 14) schizophrenic patients, as well as healthy subjects (n = 19) and septic shock patients (n = 8), were studied for comparison. We observed dramatically increased numbers of native neutrophils stained for superoxide anion production (P genes p53 (P genes did not correlate to the percentage of apoptotic neutrophils (2.0% +/- 1.3%), but in CA patients about 37% of the neutrophils show morphologic signs of apoptosis (P genes decreased significantly. In conclusion, high production of reactive oxygen species in neutrophils of clozapine-treated patients, together with increased expression of proapoptotic genes, suggests that neutrophils are predisposed to apoptosis in schizophrenic patients under clozapine therapy. The correlation between drug and proapoptotic markers was highest for clozapine and bax alpha as well as superoxide anion radicals. This indicates oxidative mitochondrial stress in neutrophils of clozapine-treated patients which probably contributes to the induction of apoptosis and sudden loss of neutrophils and their precursors in CA patients.

  12. The Contribution of Cell Surface Components to the Neutrophil Mechanosensitivity to Shear Stresses

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    Michael L. Akenhead

    2015-08-01

    Full Text Available This review discusses the regulation of neutrophils by fluid shear stress in the context of factors that may govern cell mechanosensitivity and its influence on cell functions. There is substantial evidence that mechanoreceptors located on the peripheral membrane contribute to the ability of shear stress to regulate cell activity. In the case of neutrophils, the formyl peptide receptor (FPR and the CD18 integrins on the cell membrane have been shown to provide neutrophils with the ability to sense shear stresses in their local environment and alter their physiological state, accordingly. This configuration is also found for other types of cells, although they involve different cell-specific mechanoreceptors. Moreover, from an examination of the neutrophil mechanotransducing capacity, it is apparent that cellular mechanosensitivity depends on a number of factors that, if altered, contribute to dysregulation and ultimately pathophysiology. To exemplify this, we first describe the neutrophil responses to shear exposure. We then review two neutrophil mechanoreceptors, specifically FPR and CD18 integrins, which participate in controlling cell activity levels under physiological conditions. Next, we discuss the various factors that may alter neutrophil mechanosensitivity to shear stress and how these may underlie the circulatory pathobiology of two cardiovascular disease states: hypertension and hypercholesterolemia. Based on the material presented, it is conceivable that cell mechanosensitivity is a powerful global metric that permits a more efficient approach to understanding the contribution of mechanobiology to physiology and to disease processes.

  13. Morphology and staining behavior of neutrophilic and eosinophilic granulocytes of the common marmoset (Callithrix jacchus).

    Science.gov (United States)

    Bleyer, Martina; Curths, Christoph; Dahlmann, Franziska; Wichmann, Judy; Bauer, Natali; Moritz, Andreas; Braun, Armin; Knauf, Sascha; Kaup, Franz-Josef; Gruber-Dujardin, Eva

    2016-06-01

    Common marmosets (Callithrix jacchus) are frequently used as translational animal models for human diseases. However, a comparative study of cytological and histochemical detection methods as well as morphometric and ultrastructural characterization of neutrophils and eosinophils in this species is lacking. Blood samples of house dust mite sensitized and allergen challenged as well as lipopolysaccharide (LPS) challenged marmosets were analyzed with different cytological and histological staining methods. Furthermore, cell size and number of nuclear segments were compared between neutrophils and eosinophils. Electron microscopy was performed to characterize the ultrastructure of granulocytes. Of all applied cytological stains, three allowed differentiation of eosinophils and neutrophils and, thus, reliable quantification in blood smears: May-Grünwald-Giemsa stain, Congo Red and Naphthol AS-D Chloroacetate-Esterase. For histology, Hematoxylin-Eosin (H&E) could not demonstrate clear differences, whereas Sirius Red, Congo Red, and Naphthol AS-D Chloroacetate Esterase showed capable results for identification of eosinophils or neutrophils in lung tissue. Morphometry revealed that marmoset neutrophils have more nuclear segments and are slightly larger than eosinophils. Ultrastructurally, eosinophils presented with large homogeneous electron-dense granules without crystalloid cores, while neutrophils were characterized by heterogeneous granules of different size and density. Additionally, sombrero-like vesicles were detected in tissue eosinophils of atopic marmosets, indicative for hypersensitivity-related piecemeal degranulation. In conclusion, we provide a detailed overview of marmoset eosinophils and neutrophils, important for phenotypic characterization of marmoset models for human airway diseases.

  14. Serum and Glucocorticoid Regulated Kinase 1 (SGK1) Regulates Neutrophil Clearance During Inflammation Resolution

    Science.gov (United States)

    Burgon, Joseph; Robertson, Anne L.; Sadiku, Pranvera; Wang, Xingang; Hooper-Greenhill, Edward; Prince, Lynne R.; Walker, Paul; Hoggett, Emily E.; Ward, Jonathan R.; Farrow, Stuart N.; Zuercher, William J.; Jeffrey, Philip; Savage, Caroline O.; Ingham, Philip W.; Hurlstone, Adam F.; Whyte, Moira K. B.; Renshaw, Stephen A.

    2013-01-01

    The inflammatory response is integral to maintaining health, by functioning to resist microbial infection and repair tissue damage. Large numbers of neutrophils are recruited to inflammatory sites to neutralise invading bacteria through phagocytosis and the release of proteases and reactive oxygen species into the extracellular environment. Removal of the original inflammatory stimulus must be accompanied by resolution of the inflammatory response, including neutrophil clearance, to prevent inadvertent tissue damage. Neutrophil apoptosis and its temporary inhibition by survival signals provides a target for anti-inflammatory therapeutics, making it essential to better understand this process. GM-CSF, a neutrophil survival factor, causes a significant increase in mRNA levels for the known anti-apoptotic protein Serum and Glucocorticoid Regulated Kinase 1 (SGK1). We have characterised the expression patterns and regulation of SGK family members in human neutrophils, and shown that inhibition of SGK activity completely abrogates the anti-apoptotic effect of GM-CSF. Using a transgenic zebrafish model, we have disrupted sgk1 gene function and shown this specifically delays inflammation resolution, without altering neutrophil recruitment to inflammatory sites in vivo. These data suggest SGK1 plays a key role in regulating neutrophil survival signalling, and thus may prove a valuable therapeutic target for the treatment of inflammatory disease. PMID:24431232

  15. Serum and glucocorticoid-regulated kinase 1 regulates neutrophil clearance during inflammation resolution.

    Science.gov (United States)

    Burgon, Joseph; Robertson, Anne L; Sadiku, Pranvera; Wang, Xingang; Hooper-Greenhill, Edward; Prince, Lynne R; Walker, Paul; Hoggett, Emily E; Ward, Jonathan R; Farrow, Stuart N; Zuercher, William J; Jeffrey, Philip; Savage, Caroline O; Ingham, Philip W; Hurlstone, Adam F; Whyte, Moira K B; Renshaw, Stephen A

    2014-02-15

    The inflammatory response is integral to maintaining health by functioning to resist microbial infection and repair tissue damage. Large numbers of neutrophils are recruited to inflammatory sites to neutralize invading bacteria through phagocytosis and the release of proteases and reactive oxygen species into the extracellular environment. Removal of the original inflammatory stimulus must be accompanied by resolution of the inflammatory response, including neutrophil clearance, to prevent inadvertent tissue damage. Neutrophil apoptosis and its temporary inhibition by survival signals provides a target for anti-inflammatory therapeutics, making it essential to better understand this process. GM-CSF, a neutrophil survival factor, causes a significant increase in mRNA levels for the known anti-apoptotic protein serum and glucocorticoid-regulated kinase 1 (SGK1). We have characterized the expression patterns and regulation of SGK family members in human neutrophils and shown that inhibition of SGK activity completely abrogates the antiapoptotic effect of GM-CSF. Using a transgenic zebrafish model, we have disrupted sgk1 gene function and shown this specifically delays inflammation resolution, without altering neutrophil recruitment to inflammatory sites in vivo. These data suggest SGK1 plays a key role in regulating neutrophil survival signaling and thus may prove a valuable therapeutic target for the treatment of inflammatory disease.

  16. Neutrophils are immuno-modulatory in rhinovirus infections

    NARCIS (Netherlands)

    Tang, Francesca; Hansbro, Philip; Burgess, Janette; Baines, Katherine; Oliver, Brian

    2015-01-01

    Background: Neutrophils are important in controlling bacterial infections however; their role in viral infections remains unclear. Previously, we found that neutrophils respond to viral mimetics but not replication competent rhinovirus (RV). Aim: To investigate if neutrophils are activated when expo

  17. Neutrophil-induced injury of rat pulmonary alveolar epithelial cells.

    Science.gov (United States)

    Simon, R H; DeHart, P D; Todd, R F

    1986-11-01

    The damage to pulmonary alveolar epithelial cells that occurs in many inflammatory conditions is thought to be caused in part by phagocytic neutrophils. To investigate this process, we exposed monolayers of purified rat alveolar epithelial cells to stimulated human neutrophils and measured cytotoxicity using a 51Cr-release assay. We found that stimulated neutrophils killed epithelial cells by a process that did not require neutrophil-generated reactive oxygen metabolites. Pretreatment of neutrophils with an antibody (anti-Mo1) that reduced neutrophil adherence to epithelial cells limited killing. Although a variety of serine protease inhibitors partially inhibited cytotoxicity, we found that neutrophil cytoplasts, neutrophil lysates, neutrophil-conditioned medium, purified azurophilic or specific granule contents, and purified human neutrophil elastase did not duplicate the injury. We conclude that stimulated neutrophils can kill alveolar epithelial cells in an oxygen metabolite-independent manner. Tight adherence of stimulated neutrophils to epithelial cell monolayers appears to promote epithelial cell killing.

  18. Modulation of polymorphonuclear neutrophil functions by astrocytes

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    Xie Luokun

    2010-09-01

    Full Text Available Abstract Background Neuroinflammation is a complex process involving cells from the immune system and the central nerve system (CNS. Polymorphonuclear neutrophils (PMN are the most abundant class of white blood cells, and typically the first type of leukocyte recruited to sites of inflammation. In the CNS, astrocytes are the most abundant glial cell population and participate in the local innate immune response triggered by a variety of insults. In the present study, we investigated the impacts of astrocytes on PMN function. Methods Primary astrocyte cultures were derived from postnatal C57BL/6 mice and primary neutrophils were isolated from 8 to 12 weeks old C57BL/6 mice. PMNs respiratory burst was analyzed by H2DCFDA assay. For phagocytosis assay, neutrophils were incubated with FITC-labeled E. coli and the phagocytosis of E coli was determined by flow cytometer. PMNs degranulation was determined by myeloperoxidase assay. Cytokine expression was determined by real-time PCR. To determine the involvement of different signaling pathway, protein lysates were prepared and western blots were conducted to assess the activation of Akt, Erk1/2, and p38. Results Using ex vivo neutrophils and primary astrocyte cultures, our study demonstrated that astrocytes differentially regulate neutrophil functions, depending upon whether the interactions between the two cell types are direct or indirect. Upon direct cell-cell contact, astrocytes attenuate neutrophil apoptosis, respiratory bust, and degranulation, while enhancing neutrophil phagocytic capability and pro-inflammatory cytokine expression. Through indirect interaction with neutrophils, astrocytes attenuate apoptosis and enhance necrosis in neutrophils, augment neutrophil phagocytosis and respiratory burst, and inhibit neutrophil degranulation. In addition, astrocytes could augment Akt, Erk1/2, and p38 activation in neutrophils. Conclusions Astrocytes differentially regulate neutrophil functions through

  19. VanderLaan Circulant Type Matrices

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    Hongyan Pan

    2015-01-01

    Full Text Available Circulant matrices have become a satisfactory tools in control methods for modern complex systems. In the paper, VanderLaan circulant type matrices are presented, which include VanderLaan circulant, left circulant, and g-circulant matrices. The nonsingularity of these special matrices is discussed by the surprising properties of VanderLaan numbers. The exact determinants of VanderLaan circulant type matrices are given by structuring transformation matrices, determinants of well-known tridiagonal matrices, and tridiagonal-like matrices. The explicit inverse matrices of these special matrices are obtained by structuring transformation matrices, inverses of known tridiagonal matrices, and quasi-tridiagonal matrices. Three kinds of norms and lower bound for the spread of VanderLaan circulant and left circulant matrix are given separately. And we gain the spectral norm of VanderLaan g-circulant matrix.

  20. On the maturation rate of the neutrophil.

    Science.gov (United States)

    Zajicek, G; Shohat, M; Polliack, A

    1984-05-01

    Fifty-three maturing bone marrow cells of the granulocyte cell series stained with Giemsa stain and magnified 1,000 times were scanned by a "computerized microscope" consisting of a LSI-11/23 microprocessor and a black-and-white video camera attached to a "frame grabber ." Each sampled cell was digitized into 70 X 70 pixels, each pixel representing 0.04 micron of the real image. The pixel gray values ranged between 0 and 255. Zero stood for white, 255 represented black, while the numbers in between stood for the various shades of gray. The cells represented six different stages of granulocytic maturation: myeloblast, promyelocyte, myelocyte, metamyelocyte , band form, and polymorphonuclear granulocyte. A discriminant analysis program selected 19 features best distinguishing between the six different cell types and computed five canonical discriminant functions defining a Space in which maturation was studied. In the Space, distance between two cells serves as a measure of similarity. The closer two cells are, the more similar they are and vice versa. This measure was applied here to express the degree of similarity between the neutrophil maturation classes, and since they represent states in the neutrophil life history, it is applicable also as a yardstick for the quantitation of differentiation. In the Space, the life history of a cell is represented by a trajectory originating in the myeloblast and terminating in the granulocyte state. Displacement along the trajectory represents cell maturation that is expressed relatively to the least differentiated state of the myeloblast. The further a cell from this state the more mature it is. The same yardstick also serves for differentiation rate estimates represented in the Space by displacement velocities that are derived from the known "transit times" of a cell in each state. The methodology is also applied for cell production estimates. Unlike other "computerized microscopes" serving for cell classification, the

  1. IL-1 Coordinates the Neutrophil Response to C. albicans in the Oral Mucosa

    Science.gov (United States)

    Altmeier, Simon; Toska, Albulena; Sparber, Florian; Teijeira, Alvaro; Halin, Cornelia; LeibundGut-Landmann, Salomé

    2016-01-01

    Mucosal infections with Candida albicans belong to the most frequent forms of fungal diseases. Host protection is conferred by cellular immunity; however, the induction of antifungal immunity is not well understood. Using a mouse model of oropharyngeal candidiasis (OPC) we show that interleukin-1 receptor (IL-1R) signaling is critical for fungal control at the onset of infection through its impact on neutrophils at two levels. We demonstrate that both the recruitment of circulating neutrophils to the site of infection and the mobilization of newly generated neutrophils from the bone marrow depended on IL-1R. Consistently, IL-1R-deficient mice displayed impaired chemokine production at the site of infection and defective secretion of granulocyte colony-stimulating factor (G-CSF) in the circulation in response to C. albicans. Strikingly, endothelial cells were identified as the primary cellular source of G-CSF during OPC, which responded to IL-1α that was released from keratinocytes in the infected tissue. The IL-1-dependent crosstalk between two different cellular subsets of the nonhematopoietic compartment was confirmed in vitro using a novel murine tongue-derived keratinocyte cell line and an established endothelial cell line. These data establish a new link between IL-1 and granulopoiesis in the context of fungal infection. Together, we identified two complementary mechanisms coordinating the neutrophil response in the oral mucosa, which is critical for preventing fungal growth and dissemination, and thus protects the host from disease. PMID:27632536

  2. Impaired phagosomal maturation in neutrophils leads to periodontitis in lysosomal-associated membrane protein-2 knockout mice

    NARCIS (Netherlands)

    Beertsen, W.; Willenborg, M.; Everts, V.; Zirogianni, A.; Podschun, R.; Schröder, B.; Eskelinen, E.L.; Saftig, P.

    2008-01-01

    Inflammatory periodontal diseases constitute one of the most common infections in humans, resulting in the destruction of the supporting structures of the dentition. Circulating neutrophils are an essential component of the human innate immune system. We observed that mice deficient for the major ly

  3. Inflammatory response and extracorporeal circulation.

    Science.gov (United States)

    Kraft, Florian; Schmidt, Christoph; Van Aken, Hugo; Zarbock, Alexander

    2015-06-01

    Patients undergoing cardiac surgery with extracorporeal circulation (EC) frequently develop a systemic inflammatory response syndrome. Surgical trauma, ischaemia-reperfusion injury, endotoxaemia and blood contact to nonendothelial circuit compounds promote the activation of coagulation pathways, complement factors and a cellular immune response. This review discusses the multiple pathways leading to endothelial cell activation, neutrophil recruitment and production of reactive oxygen species and nitric oxide. All these factors may induce cellular damage and subsequent organ injury. Multiple organ dysfunction after cardiac surgery with EC is associated with an increased morbidity and mortality. In addition to the pathogenesis of organ dysfunction after EC, this review deals with different therapeutic interventions aiming to alleviate the inflammatory response and consequently multiple organ dysfunction after cardiac surgery.

  4. Tumour necrosis factor-alpha and interleukin-8 inhibit neutrophil migration in vitro and in vivo

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    F. Q. Cunha

    1992-01-01

    Full Text Available Pretreatment of human neutrophils with recombinant tumour necrosis factor-alpha (rTNF-α and/or interleukin-8 (rIL-8, but not with either transforming growth factor-beta, interleukin-6 or interferon-gamma, rendered these cells less responsive to FMLP, in microchemotaxis assays. This inhibitory effect was dose dependent and more powerful when neutrophils were pretreated with a mixture of both cytokines. Intravenous injection of human rIL-8 (hrIL-8 and/or murine rTNF-α (mrTNF-α also significantly reduced in vivo neutrophil migration into peritoneal cavities of rats stimulated with carrageenan. These data suggest that the defect in neutrophil migration during septicaemia or endotoxaemia may be the result of the continuous release of IL-8 and TNF-α into the circulation. Thus, either the selective control or blockade of releasing of these cytokines as well as of its effects on neutrophils may be clinically useful in reestablishing the cell defence mechanisms.

  5. Synchronized integrin engagement and chemokine activation is crucial in neutrophil extracellular trap-mediated sterile inflammation.

    Science.gov (United States)

    Rossaint, Jan; Herter, Jan M; Van Aken, Hugo; Napirei, Markus; Döring, Yvonne; Weber, Christian; Soehnlein, Oliver; Zarbock, Alexander

    2014-04-17

    There is emerging evidence that neutrophil extracellular traps (NETs) play important roles in inflammatory processes. Here we report that neutrophils have to be simultaneously activated by integrin-mediated outside-in- and G-protein-coupled receptor (GPCR) signaling to induce NET formation in acute lung injury (ALI), which is associated with a high mortality rate in critically ill patients. NETs consist of decondensed chromatin decorated with granular and cytosolic proteins and they can trap extracellular pathogens. The prerequisite for NET formation is the activation of neutrophils and the release of their DNA. In a neutrophil- and platelet-dependent mouse model of ventilator-induced lung injury (VILI), NETs were found in the lung microvasculature, and circulating NET components increased in the plasma. In this model, blocking integrin-mediated outside-in or either GPCR-signaling or heteromerization of platelet chemokines decreased NET formation and lung injury. Targeting NET components by DNAse1 application or neutrophil elastase-deficient mice protected mice from ALI, whereas DNase1(-/-)/Trap1(m/m) mice had an aggravated ALI, suggesting that NETs directly influence the severity of ALI. These data suggest that NETs form in the lungs during VILI, contribute to the disease process, and thus may be a promising new direction for the treatment of ALI.

  6. Febrile-range hyperthermia augments pulmonary neutrophil recruitment and amplifies pulmonary oxygen toxicity.

    Science.gov (United States)

    Hasday, Jeffrey D; Garrison, Allen; Singh, Ishwar S; Standiford, Theodore; Ellis, Garrettson S; Rao, Srinivas; He, Ju-Ren; Rice, Penny; Frank, Mariah; Goldblum, Simeon E; Viscardi, Rose M

    2003-06-01

    Febrile-range hyperthermia (FRH) improves survival in experimental infections by accelerating pathogen clearance, but may also increase collateral tissue injury. We hypothesized that FRH would worsen the outcome of inflammation stimulated by a non-replicating agonist and tested this hypothesis in a murine model of pulmonary oxygen toxicity. Using a conscious, temperature-controlled mouse model, we showed that maintaining a core temperature at FRH (39 degrees C to 40 degrees C) rather than at euthermic levels (36.5 degrees C to 37 degrees C) during hyperoxia exposure accelerated lethal pulmonary vascular endothelial injury, reduced the inspired oxygen threshold for lethality, induced expression of granulocyte-colony stimulating factor, and expanded the circulating neutrophil pool. In these same mice, FRH augmented pulmonary expression of the ELR(+) CXC chemokines, KC and LPS-induced CXC chemokine, enhanced recruitment of neutrophils, and changed the histological pattern of lung injury to a neutrophilic interstitial pneumonitis. Immunoblockade of CXC receptor-2 abrogated neutrophil recruitment, reduced pulmonary vascular injury, and delayed death. These combined data demonstrate that FRH may enlist distinct mediators and effector cells to profoundly shift the host response to a defined injurious stimulus, in part by augmenting delivery of neutrophils to sites of inflammation, such as may occur in infections. In certain conditions, such as in the hyperoxic lung, this process may be deleterious.

  7. Neutrophil granules in health and disease

    DEFF Research Database (Denmark)

    Häger, M; Cowland, J B; Borregaard, N

    2010-01-01

    Neutrophil granules store proteins that are critically important for the neutrophil to move from the vascular bed to tissues and to kill microorganisms. This is illustrated in nature when individual proteins are deleted due to inherited mutations of their cognate genes, and such deficiencies resu...

  8. Neutrophils: potential therapeutic targets in tularemia?

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    Lee-Ann H Allen

    2013-12-01

    Full Text Available The central role of neutrophils in innate immunity and host defense has long been recognized, and the ability of these cells to efficiently engulf and kill invading bacteria has been extensively studied, as has the role of neutrophil apoptosis in resolution of the inflammatory response. In the past few years additional immunoregulatory properties of neutrophils were discovered, and it is now clear that these cells play a much greater role in control of the immune response than was previously appreciated. In this regard, it is noteworthy that Francisella tularensis is one of relatively few pathogens that can successfully parasitize neutrophils as well as macrophages, DC and epithelial cells. Herein we will review the mechanisms used by F. tularensis to evade elimination by neutrophils. We will also reprise effects of this pathogen on neutrophil migration and lifespan as compared with other infectious and inflammatory disease states. In addition, we will discuss the evidence which suggests that neutrophils contribute to disease progression rather than effective defense during tularemia, and consider whether manipulation of neutrophil migration or turnover may be suitable adjunctive therapeutic strategies.

  9. Proteases, neutrophils, and periodontitis: the NET effect.

    Science.gov (United States)

    Nauseef, William M

    2014-10-01

    Neutrophils exert potent antimicrobial activities in their role as first-line cellular defenders against infection. The synergistic and collective actions of oxidants and granule proteins, including serine proteases, support the microbial killing in phagosomes, where most neutrophil-mediated antimicrobial action occurs. In addition to phagocytosis, specific stimuli prompt neutrophils to extrude a matrix of DNA, histones, and granule proteins to produce neutrophil extracellular traps (NETs), which can trap microbes. Mice lacking the serine proteases necessary for NET production are more susceptible to infection, an observation suggesting that functional NETs are required for host protection. In this issue of the JCI, Sørensen and colleagues characterize neutrophils from a patient with Papillon-Lefèvre syndrome. The patient has an inactivating mutation in the gene encoding dipeptidyl peptidase I, resulting in neutrophils lacking elastase, a serine protease required for NET production. Despite the inability to form NETS, neutrophils from this patient killed pathogens in vitro, and the patient did not exhibit evidence of an increased propensity toward bacterial infections. Together, these results suggest that proteases in human neutrophils are dispensable for protection against bacterial infection and that the ability to generate NETs in vitro does not compromise host defense.

  10. Alcohol-related changes in the intestinal microbiome influence neutrophil infiltration, inflammation and steatosis in early alcoholic hepatitis in mice

    Science.gov (United States)

    Satishchandran, Abhishek; Iracheta-Vellve, Arvin; Ambade, Aditya; Kodys, Karen; Catalano, Donna; Ward, Doyle V.; Szabo, Gyongyi

    2017-01-01

    Background Alcohol-induced intestinal dysbiosis disrupts homeostatic gut-liver axis function and is essential in the development of alcoholic liver disease. Here, we investigate changes in enteric microbiome composition in a model of early alcoholic steatohepatitis and dissect the pathogenic role of intestinal microbes in alcohol-induced liver pathology. Materials and methods Wild type mice received a 10-day diet that was either 5% alcohol-containing or an isocaloric control diet plus a single binge. 16S rDNA sequencing defined the bacterial communities in the cecum of alcohol- and pair-fed animals. Some mice were treated with an antibiotic cocktail prior to and throughout alcohol feeding. Liver neutrophils, cytokines and steatosis were evaluated. Results Acute-on-chronic alcohol administration induced shifts in various bacterial phyla in the cecum, including increased Actinobacteria and a reduction in Verrucomicrobia driven entirely by a reduction in the genus Akkermansia. Antibiotic treatment reduced the gut bacterial load and circulating bacterial wall component lipopolysaccharide (LPS). We found that bacterial load suppression prevented alcohol-related increases in the number of myeloperoxidase- (MPO) positive infiltrating neutrophils in the liver. Expression of liver mRNA tumor necrosis factor alpha (Tnfα), C-X-C motif chemokine ligand 1 (Cxcl1) and circulating protein monocyte chemoattractant protein-1 (MCP-1) were also reduced in antibiotic-treated alcohol-fed mice. Alcohol-induced hepatic steatosis measured by Oil-Red O staining was significantly reduced in antibiotic treated mice. Genes regulating lipid production and storage were also altered by alcohol and antibiotic treatment. Interestingly, antibiotic treatment did not protect from alcohol-induced increases in serum aminotransferases (ALT/AST). Conclusions Our data indicate that acute-on-chronic alcohol feeding alters the microflora at multiple taxonomic levels and identifies loss of Akkermansia as an

  11. Evasion of Neutrophil Killing by Staphylococcus aureus

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    Will A. McGuinness

    2016-03-01

    Full Text Available Staphylococcus aureus causes many types of infections, ranging from self-resolving skin infections to severe or fatal pneumonia. Human innate immune cells, called polymorphonuclear leukocytes (PMNs or neutrophils, are essential for defense against S. aureus infections. Neutrophils are the most prominent cell type of the innate immune system and are capable of producing non-specific antimicrobial molecules that are effective at eliminating bacteria. Although significant progress has been made over the past few decades, our knowledge of S. aureus-host innate immune system interactions is incomplete. Most notably, S. aureus has the capacity to produce numerous molecules that are directed to protect the bacterium from neutrophils. Here we review in brief the role played by neutrophils in defense against S. aureus infection, and correspondingly, highlight selected S. aureus molecules that target key neutrophil functions.

  12. Neutrophilic inflammatory response and oxidative stress in premenopausal women chronically exposed to indoor air pollution from biomass burning.

    Science.gov (United States)

    Banerjee, Anirban; Mondal, Nandan Kumar; Das, Debangshu; Ray, Manas Ranjan

    2012-04-01

    The possibility of inflammation and neutrophil activation in response to indoor air pollution (IAP) from biomass fuel use has been investigated. For this, 142 premenopausal, never-smoking women (median age, 34 years) who cook exclusively with biomass (wood, dung, crop wastes) and 126 age-matched control women who cook with cleaner fuel liquefied petroleum gas (LPG) were enrolled. The neutrophil count in blood and sputum was significantly higher (p enzyme-linked immunosorbent assay showed that they had 72%, 67%, and 54% higher plasma levels of the proinflammatory cytokines tumor necrosis factor-alpha, interleukin-6, and interleukin-12, respectively, and doubled neutrophil chemoattractant interleukin-8. Immunocytochemical study revealed significantly higher percentage of airway neutrophils expressing inducible nitric oxide synthase, while the serum level of nitric oxide was doubled in women who cooked with biomass. Spectrophotometric analysis documented higher myeloperoxidase activity in circulating neutrophils of biomass users, suggesting neutrophil activation. Flow cytometry showed excess generation of reactive oxygen species (ROS) by leukocytes of biomass-using women, whereas their erythrocytes contained a depleted level of antioxidant enzyme superoxide dismutase (SOD). Indoor air of biomass-using households had two to four times more particulate matter with diameters of <10 μm (PM(10)) and <2.5 μm (PM(2.5)) as measured by real-time laser photometer. After controlling potential confounders, rise in proinflammatory mediators among biomass users were positively associated with PM(10) and PM(2.5) in indoor air, suggesting a close relationship between IAP and neutrophil activation. Besides, the levels of neutrophil activation and inflammation markers were positively associated with generation of ROS and negatively with SOD, indicating a role of oxidative stress in mediating neutrophilic inflammatory response following chronic inhalation of biomass smoke.

  13. Dynamic interactions of neutrophils and biofilms

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    Josefine Hirschfeld

    2014-12-01

    Full Text Available Background: The majority of microbial infections in humans are biofilm-associated and difficult to treat, as biofilms are highly resistant to antimicrobial agents and protect themselves from external threats in various ways. Biofilms are tenaciously attached to surfaces and impede the ability of host defense molecules and cells to penetrate them. On the other hand, some biofilms are beneficial for the host and contain protective microorganisms. Microbes in biofilms express pathogen-associated molecular patterns and epitopes that can be recognized by innate immune cells and opsonins, leading to activation of neutrophils and other leukocytes. Neutrophils are part of the first line of defense and have multiple antimicrobial strategies allowing them to attack pathogenic biofilms. Objective/design: In this paper, interaction modes of neutrophils with biofilms are reviewed. Antimicrobial strategies of neutrophils and the counteractions of the biofilm communities, with special attention to oral biofilms, are presented. Moreover, possible adverse effects of neutrophil activity and their biofilm-promoting side effects are discussed. Results/conclusion: Biofilms are partially, but not entirely, protected against neutrophil assault, which include the processes of phagocytosis, degranulation, and formation of neutrophil extracellular traps. However, virulence factors of microorganisms, microbial composition, and properties of the extracellular matrix determine whether a biofilm and subsequent microbial spread can be controlled by neutrophils and other host defense factors. Besides, neutrophils may inadvertently contribute to the physical and ecological stability of biofilms by promoting selection of more resistant strains. Moreover, neutrophil enzymes can degrade collagen and other proteins and, as a result, cause harm to the host tissues. These parameters could be crucial factors in the onset of periodontal inflammation and the subsequent tissue breakdown.

  14. Cytobiologic and clinical aspects in a patient with chronic neutrophilic leukemia after thorotrast exposure

    Energy Technology Data Exchange (ETDEWEB)

    Boggs, D.R.; Kaplan, S.S.

    1986-11-01

    A patient with fairly typical chronic neutrophilic leukemia, as represented by some two dozen such reported cases, had been given Thorotrast more than 20 years before. Typical myeloblastic crisis developed with remarkable terminal leukocytosis. Mature blood neutrophils had normal function with respect to phagocytosis, bacterial killing, metabolic activation, and chemotactic response. The number of cells producing colonies of neutrophils and monocytes in in vitro semisolid cultures was normal in the blood and increased in marrow. Colony size was smaller than is usually observed in normal patients or in typical patients with chronic myeloid leukemia. Termination in blast crisis, also seen in a few other patients with chronic neutrophilic leukemia, indicates that this is indeed a form of leukemia and not a leukemoid reaction of obscure cause. The differential diagnosis of extreme neutrophilia is discussed.

  15. Circulation economics

    DEFF Research Database (Denmark)

    Ingebrigtsen, Stig; Jakobsen, Ove

    2006-01-01

    Purpose - This paper is an attempt to advance the critical discussion regarding environmental and societal responsibility in economics and business. Design/methodology/approach - The paper presents and discusses as a holistic, organic perspective enabling innovative solutions to challenges...... concerning the responsible and efficient use of natural resources and the constructive interplay with culture. To reach the goal of sustainable development, the paper argues that it is necessary to make changes in several dimensions in mainstream economics. This change of perspective is called a turn towards...... presupposes a perspective integrating economic, natural and cultural values. Third, to organize the interplay between all stakeholders we introduce an arena for communicative cooperation. Originality/value - The paper concludes that circulation economics presupposes a change in paradigm, from a mechanistic...

  16. Cytokines induced neutrophil extracellular traps formation: implication for the inflammatory disease condition.

    Directory of Open Access Journals (Sweden)

    Ravi S Keshari

    Full Text Available Neutrophils (PMNs and cytokines have a critical role to play in host defense and systemic inflammatory response syndrome (SIRS. Neutrophil extracellular traps (NETs have been shown to extracellularly kill pathogens, and inflammatory potential of NETs has been shown. Microbial killing inside the phagosomes or by NETs is mediated by reactive oxygen and nitrogen species (ROS/RNS. The present study was undertaken to assess circulating NETs contents and frequency of NETs generation by isolated PMNs from SIRS patients. These patients displayed significant augmentation in the circulating myeloperoxidase (MPO activity and DNA content, while PMA stimulated PMNs from these patients, generated more free radicals and NETs. Plasma obtained from SIRS patients, if added to the PMNs isolated from healthy subjects, enhanced NETs release and free radical formation. Expressions of inflammatory cytokines (IL-1β, TNFα and IL-8 in the PMNs as well as their circulating levels were significantly augmented in SIRS subjects. Treatment of neutrophils from healthy subjects with TNFα, IL-1β, or IL-8 enhanced free radicals generation and NETs formation, which was mediated through the activation of NADPH oxidase and MPO. Pre-incubation of plasma from SIRS with TNFα, IL-1β, or IL-8 antibodies reduced the NETs release. Role of IL-1β, TNFα and IL-8 thus seems to be involved in the enhanced release of NETs in SIRS subjects.

  17. Neutrophil Extracellular Traps and Microcrystals

    Science.gov (United States)

    2017-01-01

    Neutrophil extracellular traps represent a fascinating mechanism by which PMNs entrap extracellular microbes. The primary purpose of this innate immune mechanism is thought to localize the infection at an early stage. Interestingly, the ability of different microcrystals to induce NET formation has been recently described. Microcrystals are insoluble crystals with a size of 1–100 micrometers that have different composition and shape. Microcrystals have it in common that they irritate phagocytes including PMNs and typically trigger an inflammatory response. This review is the first to summarize observations with regard to PMN activation and NET release induced by microcrystals. Gout-causing monosodium urate crystals, pseudogout-causing calcium pyrophosphate dehydrate crystals, cholesterol crystals associated with atherosclerosis, silicosis-causing silica crystals, and adjuvant alum crystals are discussed. PMID:28373994

  18. Candida albicans escapes from mouse neutrophils.

    Science.gov (United States)

    Ermert, David; Niemiec, Maria J; Röhm, Marc; Glenthøj, Andreas; Borregaard, Niels; Urban, Constantin F

    2013-08-01

    Candida albicans, the most commonly isolated human fungal pathogen, is able to grow as budding yeasts or filamentous forms, such as hyphae. The ability to switch morphology has been attributed a crucial role for the pathogenesis of C. albicans. To mimic disseminated candidiasis in humans, the mouse is the most widely used model organism. Neutrophils are essential immune cells to prevent opportunistic mycoses. To explore potential differences between the rodent infection model and the human host, we compared the interactions of C. albicans with neutrophil granulocytes from mice and humans. We revealed that murine neutrophils exhibited a significantly lower ability to kill C. albicans than their human counterparts. Strikingly, C. albicans yeast cells formed germ tubes upon internalization by murine neutrophils, eventually rupturing the neutrophil membrane and thereby, killing the phagocyte. On the contrary, growth and subsequent escape of C. albicans are blocked inside human neutrophils. According to our findings, this blockage in human neutrophils might be a result of higher levels of MPO activity and the presence of α-defensins. We therefore outline differences in antifungal immune defense between humans and mouse strains, which facilitates a more accurate interpretation of in vivo results.

  19. Functional differentiation of normal human neutrophils.

    Science.gov (United States)

    Glasser, L; Fiederlein, R L

    1987-03-01

    In the past differentiation of human neutrophils has been defined by morphology, cytochemistry, or surface markers. In our experiments we have sequenced the various events that occur during the functional differentiation of the normal human neutrophil and have also examined some of the functional properties in relationship to surface markers and biochemical events. Granulocytes were obtained from the bone marrow and blood of hematologically normal individuals. Cells were separated into different stages of maturation by their physical properties using counterflow centrifugal elutriation and density gradient separation. Three cell fractions were obtained that were enriched for either immature myeloid cells, band neutrophils, or segmented neutrophils. Since the enriched fractions were not entirely pure, methodologies for functional assays were chosen that allowed cytologic evaluation of the functional capacity of each cell type. The criteria used to classify the stages of differentiation included both morphology by light microscopy and DNA labeling with tritiated thymidine. Various neutrophilic properties were studied: Fc receptors, complement receptors (CR1, CR3), phagocytosis of both live and dead opsonized Staphylococcus aureus, microbial killing of S aureus, NBT dye reduction after cellular stimulation with endotoxin, and chemotaxis. Our results indicate that the functional properties of the neutrophil appear in a distinct order. The sequence for the functional differentiation of the human neutrophil appears to be the following: Fc receptors----immune phagocytosis----complement receptors----oxygen-independent microbial killing----oxygen-dependent microbial killing----chemotaxis.

  20. The association of elevated reactive oxygen species levels from neutrophils with low-grade inflammation in the elderly

    Directory of Open Access Journals (Sweden)

    Suzuki Katsuhiko

    2008-10-01

    Full Text Available Abstract Background Reactive oxygen species (ROS, including free radicals, oxygen ions, and peroxides, are implicated in cell damage. The objective of this study was to investigate whether the spontaneous production of ROS from neutrophils changes with age and is associated with the conventional inflammatory markers. Results Thirty-seven elderly subjects (median age, 87, range 70–95 years and 22 young subjects (median age, 26, range 21–37 years participated in this study. Circulating levels of C-reactive protein, serum amyloid A, tumor necrosis factor-α, interleukin (IL-1, IL-6, IL-8, monocyte chemotactic protein-1, and heat shock protein (HSP70 were measured with enzyme-linked immunosorbent assays. The N-formyl-methionyl-leucyl-phenylalanine and lipopolysaccharide-stimulated ROS of neutrophils were quantified by flow cytometry. Both spontaneous ROS production and circulating levels of inflammatory markers were higher in the elderly group than in the younger group. In addition, spontaneous ROS production by neutrophils was negatively associated with HSP70 in plasma. We could not find the association between spontaneous ROS production by neutrophils and the other inflammatory markers including cytokines. Conclusion The results suggest that spontaneous ROS production from neutrophils may increase with age and represent the different aspect of age-associated immune dysregulation.

  1. DETECTION OF A NEUTROPHIL CHEMOTACTIC FACTOR IN JAPANESE ENCEPHALITIS PATIENTS

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    Aditi Singh

    2012-12-01

    Full Text Available Japanese encephalitis (JE one of the most common cause of acute encephalitis in tropical regions, has generated much public anxiety in India. An early influx of macrophages followed by neutrophils at the site of injury in different organs in humans and mice has previously been reported. It correlated with production of a neutrophil chemotactic protein derived from macrophages. In the present study out of a total of 324 acute encephalitic patients, admitted in Gandhi memorial and associated hospitals, Lucknow, 121 patients with one or more indicators of JE virus infection were included. Significant pleocytosis (mean TLC value of 126+52 cells / mm3 in CSF and leucocytosis (>11,000 cells/mm3 in peripheral blood was observed at the time of admission. The leucocytosis increased significantly during second week in 67% of patients. The peripheral blood mononuclear cells culture done on alternate days was tested for chemotactic activity (hMDF, which was observed to be highest in second week of illness. The direct detection of hMDF in circulation by dot blot was positive in 92% of acute serum samples, with negligible (12.5% reactivity for convalescent sera. A correlation between the hMDF levels and severity of illness has also been observed.

  2. Lactoferrin Suppresses Neutrophil Extracellular Traps Release in Inflammation

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    Koshu Okubo

    2016-08-01

    Full Text Available Neutrophils are central players in the innate immune system. They generate neutrophil extracellular traps (NETs, which protect against invading pathogens but are also associated with the development of autoimmune and/or inflammatory diseases and thrombosis. Here, we report that lactoferrin, one of the components of NETs, translocated from the cytoplasm to the plasma membrane and markedly suppressed NETs release. Furthermore, exogenous lactoferrin shrunk the chromatin fibers found in released NETs, without affecting the generation of oxygen radicals, but this failed after chemical removal of the positive charge of lactoferrin, suggesting that charge-charge interactions between lactoferrin and NETs were required for this function. In a model of immune complex-induced NET formation in vivo, intravenous lactoferrin injection markedly reduced the extent of NET formation. These observations suggest that lactoferrin serves as an intrinsic inhibitor of NETs release into the circulation. Thus, lactoferrin may represent a therapeutic lead for controlling NETs release in autoimmune and/or inflammatory diseases.

  3. Neutrophil granules in health and disease

    DEFF Research Database (Denmark)

    Häger, M; Cowland, J B; Borregaard, N

    2010-01-01

    Neutrophil granules store proteins that are critically important for the neutrophil to move from the vascular bed to tissues and to kill microorganisms. This is illustrated in nature when individual proteins are deleted due to inherited mutations of their cognate genes, and such deficiencies result...... in the conditions leucocyte adhesion deficiency and chronic granulomatous disease. The granules of the neutrophil have traditionally been divided into two or three major types but are instead a continuum where several subtypes can be identified with differences in protein content and propensity for mobilization...

  4. Real-time detection of implant-associated neutrophil responses using a formyl peptide receptor-targeting NIR nanoprobe

    Directory of Open Access Journals (Sweden)

    Zhou J

    2012-05-01

    Full Text Available Jun Zhou*, Yi-Ting Tsai*, Hong Weng, Ewin N Tang, Ashwin Nair, Digant P Davé, Liping Tang, Department of Bioengineering, University of Texas at Arlington, Arlington, TX *Both authors contributed equally to this workAbstract: Neutrophils play an important role in implant-mediated inflammation and infection. Unfortunately, current methods which monitor neutrophil activity, including enzyme measurements and histological evaluation, require many animals and cannot be used to accurately depict the dynamic cellular responses. To understand the neutrophil interactions around implant-mediated inflammation and infection it is critical to develop methods which can monitor in vivo cellular activity in real time. In this study, formyl peptide receptor (FPR-targeting near-infrared nanoprobes were fabricated. This was accomplished by conjugating near-infrared dye with specific peptides having a high affinity to the FPRs present on activated neutrophils. The ability of FPR-targeting nanoprobes to detect and quantify activated neutrophils was assessed both in vitro and in vivo. As expected, FPR-targeting nanoprobes preferentially accumulated on activated neutrophils in vitro. Following transplantation, FPR-targeting nanoprobes preferentially accumulated at the biomaterial implantation site. Equally important, a strong relationship was observed between the extent of fluorescence intensity in vivo and the number of recruited neutrophils at the implantation site. Furthermore, FPR-targeting nanoprobes may be used to detect and quantify the number of neutrophils responding to a catheter-associated infection. The results show that FPR-targeting nanoprobes may serve as a powerful tool to monitor and measure the extent of neutrophil responses to biomaterial implants in vivo.Keywords: in vivo imaging, nanoprobe, neutrophils, inflammation, biocompatibility

  5. Early infection during burn-induced inflammatory response results in increased mortality and p38-mediated neutrophil dysfunction.

    Science.gov (United States)

    Adediran, Samuel G; Dauplaise, Derrick J; Kasten, Kevin R; Tschöp, Johannes; Dattilo, Jonathan; Goetzman, Holly S; England, Lisa G; Cave, Cindy M; Robinson, Chad T; Caldwell, Charles C

    2010-09-01

    Following burn injury, the host is susceptible to bacterial infections normally cleared by healthy patients. We hypothesized that during the systemic immune response that follows scald injury, the host's altered immune status increases infection susceptibility. Using a murine model of scald injury under inhaled anesthesia followed by intraperitoneal infection, we observed increased neutrophil numbers and function at postburn day (PBD) 1 compared with sham-burned and PBD4 mice. Further, increased mortality, bacteremia, and serum IL-6 were observed in PBD1 mice after Pseudomonas aeruginosa (PA) infection compared with sham-burned and PBD4 mice infected with PA. To examine these disparate responses, we investigated neutrophils isolated at 5 and 24 h following PA infection from PBD1 and sham-burned mice. Five hours after infection, there was no significant difference in number of recruited neutrophils; however, neutrophils from injured mice had decreased activation, active-p38, and oxidative burst compared with sham-burned mice. In direct contrast, 24 h after infection, we observed increased numbers, active-p38, and oxidative burst of neutrophils from PBD1 mice. Finally, we demonstrated that in neutrophils isolated from PBD1 mice, the observed increase in oxidative burst was p38 dependent. Altogether, neutrophil activation and function from thermally injured mice are initially delayed and later exacerbated by a p38-dependent mechanism. This mechanism is likely key to the observed increase in bacterial load and mortality of PBD1 mice infected with PA.

  6. Platelets augment respiratory burst in neutrophils activated by selected species of gram-positive or gram-negative bacteria.

    Directory of Open Access Journals (Sweden)

    Kamila Pytel

    2008-12-01

    Full Text Available Neutrophils and platelets circulate in blood system and play important physiological roles as part of immunological system. Neutrophils are the first line of host defense against various intruders, and platelets are satellite cells cooperating with other components of defense system. Recent studies report about the cooperation among these types of cells. We analyzed the effect of platelets on oxygen burst in neutrophils triggered by Staphylococcus aureus and Escherichia coli bacteria in vitro. The effect of platelets on oxygen burst in neutrophils was measured by luminol enhanced chemiluminescence. Opsonized and non-opsonized bacteria were used as activators. Activation of neutrophils with live non-opsonized and opsonized bacteria in the presence of platelets increased the oxygen burst as compared to the same system without platelets. The gram-positive bacteria (Staphylococcus aureus were causing higher activation than gram-negative bacteria (Escherichia coli. This work demonstrate that platelets potentate the response of neutrophils augmenting their respiratory burst in vitro when triggered by bacteria.

  7. Capability of Neutrophils to Form NETs Is Not Directly Influenced by a CMA-Targeting Peptide

    Science.gov (United States)

    Maueröder, Christian; Schall, Nicolas; Meyer, Frédéric; Mahajan, Aparna; Garnier, Benjamin; Hahn, Jonas; Kienhöfer, Deborah; Hoffmann, Markus H.; Muller, Sylviane

    2017-01-01

    During inflammatory reaction, neutrophils exhibit numerous cellular and immunological functions, notably the formation of neutrophil extracellular traps (NETs) and autophagy. NETs are composed of decondensed chromatin fibers coated with various antimicrobial molecules derived from neutrophil granules. NETs participate in antimicrobial defense and can also display detrimental roles and notably trigger some of the immune features of systemic lupus erythematosus (SLE) and other autoimmune diseases. Autophagy is a complex and finely regulated mechanism involved in the cell survival/death balance that may be connected to NET formation. To shed some light on the connection between autophagy and NET formation, we designed a number of experiments in human neutrophils and both in normal and lupus-prone MRL/lpr mice to determine whether the synthetic peptide P140, which is capable of selectively modulating chaperone-mediated autophagy (CMA) in lymphocytes, could alter NET formation. P140/Lupuzor™ is currently being evaluated in phase III clinical trials involving SLE patients. Overall our in vitro and in vivo studies established that P140 does not influence NET formation, cytokine/chemokine production, or CMA in neutrophils. Thus, the beneficial effect of P140/Lupuzor™ in SLE is apparently not directly related to modulation of neutrophil function. PMID:28191006

  8. 5-Lipoxygenase-Dependent Recruitment of Neutrophils and Macrophages by Eotaxin-Stimulated Murine Eosinophils

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    Ricardo Alves Luz

    2014-01-01

    Full Text Available The roles of eosinophils in antimicrobial defense remain incompletely understood. In ovalbumin-sensitized mice, eosinophils are selectively recruited to the peritoneal cavity by antigen, eotaxin, or leukotriene(LTB4, a 5-lipoxygenase (5-LO metabolite. 5-LO blockade prevents responses to both antigen and eotaxin. We examined responses to eotaxin in the absence of sensitization and their dependence on 5-LO. BALB/c or PAS mice and their mutants (5-LO-deficient ALOX; eosinophil-deficient GATA-1 were injected i.p. with eotaxin, eosinophils, or both, and leukocyte accumulation was quantified up to 24 h. Significant recruitment of eosinophils by eotaxin in BALB/c, up to 24 h, was accompanied by much larger numbers of recruited neutrophils and monocytes/macrophages. These effects were abolished by eotaxin neutralization and 5-LO-activating protein inhibitor MK886. In ALOX (but not PAS mice, eotaxin recruitment was abolished for eosinophils and halved for neutrophils. In GATA-1 mutants, eotaxin recruited neither neutrophils nor macrophages. Transfer of eosinophils cultured from bone-marrow of BALB/c donors, or from ALOX donors, into GATA-1 mutant recipients, i.p., restored eotaxin recruitment of neutrophils and showed that the critical step dependent on 5-LO is the initial recruitment of eosinophils by eotaxin, not the secondary neutrophil accumulation. Eosinophil-dependent recruitment of neutrophils in naive BALB/c mice was associated with increased binding of bacteria.

  9. Anti-neutrophil cytoplasmic antibodies in rheumatoid arthritis: two case reports and review of literature

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    Spoerl David

    2012-12-01

    Full Text Available Abstract Background Anti-neutrophil cytoplasmic antibodies are typically detected in anti-neutrophil cytoplasmic antibody associated vasculitis, but are also present in a number of chronic inflammatory non-vasculitic conditions like rheumatoid arthritis. Rare cases of granulomatosis with polyangiitis (formerly known as Wegener’s granulomatosis, a vasculitic disorder frequently associated with the presence of anti-neutrophil cytoplasmic antibodies in patients with rheumatoid arthritis have been described in literature. Case presentation We report two middle-aged female patients with rheumatoid arthritis who developed anti-neutrophil cytoplasmic antibodies and symptoms reminiscent of granulomatosis with polyangiitis. Despite the lack of antibodies specific for proteinase 3 and the absence of a classical histology, we report a probable case of granulomatosis with polyangiitis in the first patient, and consider rheumatoid vasculitis in the second patient. Conclusion Taken together with previous reports, these cases highlight that anti-neutrophil cytoplasmic antibodies have to be evaluated very carefully in patients with rheumatoid arthritis. In this context, anti-neutrophil cytoplasmic antibodies detected by indirect immunofluorescence appear to have a low diagnostic value for granulomatosis with polyangiitis. Instead they may have prognostic value for assessing the course of rheumatoid arthritis.

  10. Structural analysis of the receptors for granulocyte colony-stimulating factor on neutrophils

    Energy Technology Data Exchange (ETDEWEB)

    Hanazono, Y.; Hosoi, T.; Kuwaki, T.; Matsuki, S.; Miyazono, K.; Miyagawa, K.; Takaku, F. (Univ. of Tokyo (Japan))

    1990-11-01

    We investigated granulocyte colony-stimulating factor (G-CSF) receptors on neutrophils from three patients with chronic myelogenous leukemia (CML) in the chronic phase, in comparison with four normal volunteers. Because we experienced some difficulties in radioiodinating intact recombinant human G-CSF, we developed a new derivative of human G-CSF termed YPY-G-CSF. It was easy to iodinate this protein using the lactoperoxidase method because of two additional tyrosine residues, and its radioactivity was higher than that previously reported. The biological activity of YPY-G-CSF as G-CSF was fully retained. Scatchard analysis demonstrated that CML neutrophils had a single class of binding sites (1400 +/- 685/cell) with a dissociation constant (Kd) of 245 +/- 66 pM. The number of sites and Kd value of CML neutrophils were not significantly different from those of normal neutrophils (p greater than 0.9). Cross-linking studies revealed two specifically labeled bands of (125I)YPY-G-CSF-receptor complexes with apparent molecular masses of 160 and 110 kd on both normal and CML neutrophils. This is the first report describing two receptor proteins on neutrophils. According to the analyses of the proteolytic process of these cross-linked complexes and proteolytic mapping, we assume that alternative splicing or processing from a single gene may generate two distinct receptor proteins that bind specifically to G-CSF but have different fates in intracellular metabolism.

  11. Elevated Neutrophil Lymphocyte Ratio in Recurrent Optic Neuritis

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    Hande Guclu

    2015-01-01

    Full Text Available Purpose. To demonstrate the relation between optic neuritis (ON and systemic inflammation markers as neutrophil lymphocyte ratio (N/L ratio, platelet count, mean platelet volume (MPV, and red cell distribution width (RDW and furthermore to evaluate the utilization of these markers to predict the frequency of the ON episodes. Methods. Forty-two patients with acute ON and forty healthy subjects were enrolled into the study. The medical records were reviewed for age, sex, hemoglobin (Hb, Haematocrit (Htc, RDW, platelet count, MPV, white blood cell count (WBC, neutrophil and lymphocyte count, and neutrophil lymphocyte ratio (N/L ratio. Results. The mean N/L ratio, platelet counts, and RDW were significantly higher in ON group (p=0.000, p=0.048, and p=0.002. There was a significant relation between N/L ratio and number of episodes (r=0.492, p=0.001. There was a statistically significant difference for MPV between one episode group and recurrent ON group (p=0.035. Conclusions. Simple and inexpensive laboratory methods could help us show systemic inflammation and monitor ON patients. Higher N/L ratio can be a useful marker for predicting recurrent attacks.

  12. [Investigation of microbicidal activity of neutrophil defensins against leptospires].

    Science.gov (United States)

    Wu, Q; Xu, L; Wang, X; Li, S; Wang, B

    1992-06-01

    Defensins play an important role in oxygen-independent microbicidal mechanisms of neutrophils. They are effective against many bacteria, fungi and enveloped viruses. However, the effect of defensins upon leptospires has not been studied. In the present report, human defensins (i.e. HNP, a mixture of HNP1, HNP2 and HNP3 were prepared from human polymorphonuclear neutrophils by chromatography on Sephadex G-100 and then on Biogel P-10. Rabbit defensin NP1 was purified from rabbit peritoneal granulocytes by preparative acid urea polyacrylamide gel electrophoresis. By using the most-probable-number procedure, HNP and NP1 were tested in vitro for the killing of leptospira interrogans serogroup icteroheamorrhagiae serovar lai strain 017. NP1 was highly effective. When leptospires of strain 017 were incubated with 1 microgram/ml of NP1 at 30 degrees C for 4 hours, > 99% of these organisms were killed. HNP was less potent than NP1, and at 50 micrograms/ml, it killed > 90% of leptospires. As is also the case for the killing of bacteria, NP1 was active against leptospires in nutrient-free buffer, whereas HNP required the addition of glucose. The data suggest that defensins could play a major role in the killing of leptospires by neutrophils.

  13. Neutrophil-mediated phagocytosis of Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Jos A.G. Van Strijp

    2014-09-01

    Full Text Available For invading staphylococci, phagocytosis an killing bij human neutrophils is the biggest threat. Neutrophils are the only cells that can effectively kill staphylococci by engulfment and subsequent bombardment with proteases, amidases, antimicrobial peptides and proteins in concert with reactive oxygen species that are generated during the metabolic burst.Both complement and antibodies are crucial for effective uptake and neutrophil activation. S. aureus is not an innocent bystander in this process. It actively secretes several proteins to impair every single step in this process from receptor modulation, to complement inhibition to neutrophil lysis to protease, antimicrobial peptide inhibition and resistance to reactive oxygen species. For the design of future novel antimicrobial strategies: therapeutic antibodies, vaccines, novel antibiotics, all this should be taken into account. Still the best way to treat diseases is to help to enhance the natural defence mechanism that are already in place.

  14. Store-operated calcium signaling in neutrophils.

    Science.gov (United States)

    Clemens, Regina A; Lowell, Clifford A

    2015-10-01

    Calcium signals in neutrophils are initiated by a variety of cell-surface receptors, including formyl peptide and other GPCRs, FcRs, and integrins. The predominant pathway by which calcium enters immune cells is termed SOCE, whereby plasma membrane CRAC channels allow influx of extracellular calcium into the cytoplasm when intracellular ER stores are depleted. The identification of 2 key families of SOCE regulators, STIM calcium "sensors" and ORAI calcium channels, has allowed for genetic manipulation of SOCE pathways and provided valuable insight into the molecular mechanism of calcium signaling in immune cells, including neutrophils. This review focuses on our current knowledge of the molecules involved in neutrophil SOCE and how study of these molecules has further informed our understanding of the role of calcium signaling in neutrophil activation.

  15. Neutrophil Extracellular Traps in Periodontitis: A Web of Intrigue.

    Science.gov (United States)

    White, P C; Chicca, I J; Cooper, P R; Milward, M R; Chapple, I L C

    2016-01-01

    Neutrophil extracellular traps (NETs) represent a novel paradigm in neutrophil-mediated immunity. NETs are believed to constitute a highly conserved antimicrobial strategy comprising decondensed nuclear DNA and associated histones that are extruded into the extracellular space. Associated with the web-like strands of DNA is an array of antimicrobial peptides (AMPs), which facilitate the extracellular destruction of microorganisms that become entrapped within the NETs. NETs can be released by cells that remain viable or following a unique form of programmed cell death known as NETosis, which is dependent on the production of reactive oxygen species (ROS) and the decondensing of the nuclear DNA catalyzed by peptidyl arginine deiminase-4. NETs are produced in response to a range of pathogens, including bacteria, viruses, fungi, and protozoa, as well as host-derived mediators. NET release is, however, not without cost, as the concomitant release of cytotoxic molecules can also cause host tissue damage. This is evidenced by a number of immune-mediated diseases, in which excess or dysfunctional NET production, bacterial NET evasion, and decreased NET removal are associated with disease pathogenesis. Periodontitis is the most prevalent infectious-inflammatory disease of humans, characterized by a dysregulated neutrophilic response to specific bacterial species within the subgingival plaque biofilm. Neutrophils are the predominant inflammatory cell involved in periodontitis and have previously been found to exhibit hyperactivity and hyperreactivity in terms of ROS production in chronic periodontitis patients. However, the contribution of ROS-dependent NET formation to periodontal health or disease remains unclear. In this focused review, we discuss the mechanisms, stimuli, and requirements for NET production; the ability of NET-DNA and NET-associated AMPs to entrap and kill pathogens; and the potential immunogenicity of NETs in disease. We also speculate on the potential

  16. Photothermal image cytometry of human neutrophils

    Science.gov (United States)

    Lapotko, Dmitry

    2001-07-01

    Photothermal imaging, when being applied to the study of living cells, provides morpho-functional information about the cell populations. In technical terms, the method is complementary to optical microscopy. The photothermal method was used for cell imaging and quantitative studies. Preliminary results of the studies on living human neutrophils are presented. Differences between normal and pathological neutrophil populations from blood of healthy donors and patients with saracoidosis and pleuritis are demonstrated.

  17. Subproteome analysis of the neutrophil cytoskeleton

    OpenAIRE

    Xu, Ping; Crawford, Mark; Way, Michael; Godovac-Zimmermann, Jasminka; Segal, Anthony W.; Radulovic, Marko

    2009-01-01

    Neutrophils play a key role in the early host-defense mechanisms due to their capacity to migrate into inflamed tissues and phagocytose microorganisms. The cytoskeleton has an essential role in these neutrophil functions, however, its composition is still poorly understood. We separately analyzed different cytoskeletal compartments: cytosolic skeleton, phagosome membrane skeleton, and plasma membrane skeleton. Using a proteomic approach, 138 nonredundant proteins were identified. Proteins not...

  18. Cryptococcus neoformans modulates extracellular killing by neutrophils

    Directory of Open Access Journals (Sweden)

    Asfia eQureshi

    2011-09-01

    Full Text Available We recently established a key role for host sphingomyelin synthase (SMS in the regulation of the killing activity of neutrophils against Cryptococcus neoformans. In this work, we studied the effect of C. neoformans on the killing activity of neutrophils and whether SMS would still be a player against C. neoformans in immunocompromised mice lacking T and NK cells (Tgε26 mice. To this end, we analyzed whether C. neoformans would have any effect on neutrophil survival and killing in vitro and in vivo. We show that unlike C. albicans, neither the presence nor the capsule size of C. neoformans cells have any effect on neutrophil viability. Interestingly, melanized C. neoformans cells totally abrogated the killing activity of neutrophils. Next, we monitored how exposure of neutrophils to C. neoformans cells would interfere with any further killing activity of the medium and found that pre-incubation with live but not heat-killed fungal cells significantly inhibits further killing activity of the medium. We next studied whether activation of SMS at the site of C. neoformans infection is dependent on T and NK cells. Using matrix-assisted laser desorption-ionization (MALDI tissue imaging in infected lung we found that similarly to previous observations in the isogenic wild type CBA/J mice, SM 16:0 levels are significantly elevated at the site of infection in mice lacking T and NK cells but only at early time points. This study highlights that C. neoformans may negatively regulate the killing activity of neutrophils and that SMS activation in neutrophils appears to be partially independent of T and/or NK cells.

  19. Cryptococcus neoformans modulates extracellular killing by neutrophils.

    Science.gov (United States)

    Qureshi, Asfia; Grey, Angus; Rose, Kristie L; Schey, Kevin L; Del Poeta, Maurizio

    2011-01-01

    We recently established a key role for host sphingomyelin synthase (SMS) in regulating the killing activity of neutrophils against Cryptococcus neoformans. In this paper, we studied the effect of C. neoformans on the killing activity of neutrophils and whether SMS would still be a player against C. neoformans in immunocompromised mice lacking T and natural killer (NK) cells (Tgε26 mice). To this end, we analyzed whether C. neoformans would have any effect on neutrophil survival and killing in vitro and in vivo. We show that unlike Candida albicans, neither the presence nor the capsule size of C. neoformans cells have any effect on neutrophil viability. Interestingly, melanized C. neoformans cells totally abrogated the killing activity of neutrophils. We monitored how exposure of neutrophils to C. neoformans cells would interfere with any further killing activity of the conditioned medium and found that pre-incubation with live but not "heat-killed" fungal cells significantly inhibits further killing activity of the medium. We then studied whether activation of SMS at the site of C. neoformans infection is dependent on T and NK cells. Using matrix-assisted laser desorption-ionization tissue imaging in infected lung we found that similar to previous observations in the isogenic wild-type CBA/J mice, SM 16:0 levels are significantly elevated at the site of infection in mice lacking T and NK cells, but only at early time points. This study highlights that C. neoformans may negatively regulate the killing activity of neutrophils and that SMS activation in neutrophils appears to be partially independent of T and/or NK cells.

  20. Clinical Microfluidics for Neutrophil Genomics and Proteomics

    OpenAIRE

    2010-01-01

    Neutrophils play critical roles in modulating the immune response. We present a robust methodology for rapidly isolating neutrophils directly from whole blood and develop ‘on-chip’ processing for mRNA and protein isolation for genomics and proteomics. We validate this device with an ex vivo stimulation experiment and by comparison with standard bulk isolation methodologies. Lastly, we implement this tool as part of a near patient blood processing system within a multi-center clinical study of...

  1. Neutrophils in asthma--a review.

    Science.gov (United States)

    Ciepiela, Olga; Ostafin, Magdalena; Demkow, Urszula

    2015-04-01

    Asthma is a chronic inflammatory disease, with an array of cells involved in the pathogenesis of the disease. The role of neutrophils in the development of bronchial asthma is found to be complex, as they may trigger activation of immunocompetent cells and are a potent source of free oxygen radicals and enzymes participating in airway remodeling. The review highlights the role of neutrophils in bronchial asthma.

  2. PEGylated single-walled carbon nanotubes activate neutrophils to increase production of hypochlorous acid, the oxidant capable of degrading nanotubes.

    Science.gov (United States)

    Vlasova, Irina I; Vakhrusheva, Tatyana V; Sokolov, Alexey V; Kostevich, Valeria A; Gusev, Alexandr A; Gusev, Sergey A; Melnikova, Viktoriya I; Lobach, Anatolii S

    2012-10-01

    Perspectives for the use of carbon nanotubes in biomedical applications depend largely on their ability to degrade in the body into products that can be easily cleared out. Carboxylated single-walled carbon nanotubes (c-SWCNTs) were shown to be degraded by oxidants generated by peroxidases in the presence of hydrogen peroxide. In the present study we demonstrated that conjugation of poly(ethylene glycol) (PEG) to c-SWCNTs does not interfere with their degradation by peroxidase/H(2)O(2) system or by hypochlorite. Comparison of different heme-containing proteins for their ability to degrade PEG-SWCNTs has led us to conclude that the myeloperoxidase (MPO) product hypochlorous acid (HOCl) is the major oxidant that may be responsible for biodegradation of PEG-SWCNTs in vivo. MPO is secreted mainly by neutrophils upon activation. We hypothesize that SWCNTs may enhance neutrophil activation and therefore stimulate their own biodegradation due to MPO-generated HOCl. PEG-SWCNTs at concentrations similar to those commonly used in in vivo studies were found to activate isolated human neutrophils to produce HOCl. Both PEG-SWCNTs and c-SWCNTs enhanced HOCl generation from isolated neutrophils upon serum-opsonized zymosan stimulation. Both types of nanotubes were also found to activate neutrophils in whole blood samples. Intraperitoneal injection of a low dose of PEG-SWCNTs into mice induced an increase in percentage of circulating neutrophils and activation of neutrophils and macrophages in the peritoneal cavity, suggesting the evolution of an inflammatory response. Activated neutrophils can produce high local concentrations of HOCl, thereby creating the conditions favorable for degradation of the nanotubes.

  3. Hypercholesterolemia Increases the Production of Leukotriene B4 in Neutrophils by Enhancing the Nuclear Localization of 5-Lipoxygenase

    Directory of Open Access Journals (Sweden)

    Xiao-Feng Lai

    2014-11-01

    Full Text Available Aims: Neutrophils can synthesize leukotriene B4 (LTB4 by activating the 5-lipoxygenase (5-LOsignaling pathway. LTB4 is a pro-inflammatory mediator associated with the etiology and progression of atherosclerosis. It can increase function and number of neutrophils in an autocrine manner. Since hypercholesterolemia is associated with an increase in the number and function of neutrophils, we hypothesized that this effect could be mediated through increased production of LTB4 in neutrophils. Methods/Results: Hypercholesterolemia was modeled in Wistar rats by feeding them with a high cholesterol diet. The induction of hypercholesterolemia caused an increase in the plasma levels of LTB4, following lipopolysaccharide stimulation. This effect was recapitulated in vitro, both in the presence and absence of stimulation with the activator of 5-LO, A23187. Neutrophils in hypercholesterolemia rats expressed similar total levels of 5-LO as control rats, but displayed increased nuclear localization of 5-LO, as well as elevated levels of phosphorylated 5-LO and ERK1/2. In vitro, MβCD/cholesterol complexes enriched cholesterol in neutrophils, resulted in similar changes in 5-LO/LTB4. In addition, these alterations could be inhibited with the ERK inhibitor PD98059. Conclusion: Hypercholesterolemia increases LTB4 production in neutrophils by increasing the nuclear localization of 5-LO, which is the result of its phosphorylation by activated ERK1/2.

  4. Gene expression during the generation and activation of mouse neutrophils: implication of novel functional and regulatory pathways.

    Directory of Open Access Journals (Sweden)

    Jeffrey A Ericson

    Full Text Available As part of the Immunological Genome Project (ImmGen, gene expression was determined in unstimulated (circulating mouse neutrophils and three populations of neutrophils activated in vivo, with comparison among these populations and to other leukocytes. Activation conditions included serum-transfer arthritis (mediated by immune complexes, thioglycollate-induced peritonitis, and uric acid-induced peritonitis. Neutrophils expressed fewer genes than any other leukocyte population studied in ImmGen, and down-regulation of genes related to translation was particularly striking. However, genes with expression relatively specific to neutrophils were also identified, particularly three genes of unknown function: Stfa2l1, Mrgpr2a and Mrgpr2b. Comparison of genes up-regulated in activated neutrophils led to several novel findings: increased expression of genes related to synthesis and use of glutathione and of genes related to uptake and metabolism of modified lipoproteins, particularly in neutrophils elicited by thioglycollate; increased expression of genes for transcription factors in the Nr4a family, only in neutrophils elicited by serum-transfer arthritis; and increased expression of genes important in synthesis of prostaglandins and response to leukotrienes, particularly in neutrophils elicited by uric acid. Up-regulation of genes related to apoptosis, response to microbial products, NFkB family members and their regulators, and MHC class II expression was also seen, in agreement with previous studies. A regulatory model developed from the ImmGen data was used to infer regulatory genes involved in the changes in gene expression during neutrophil activation. Among 64, mostly novel, regulatory genes predicted to influence these changes in gene expression, Irf5 was shown to be important for optimal secretion of IL-10, IP-10, MIP-1α, MIP-1β, and TNF-α by mouse neutrophils in vitro after stimulation through TLR9. This data-set and its analysis using the

  5. PEGylated single-walled carbon nanotubes activate neutrophils to increase production of hypochlorous acid, the oxidant capable of degrading nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Vlasova, Irina I., E-mail: irina.vlasova@yahoo.com [Research Institute for Physico-Chemical Medicine, Federal Medico-Biological Agency, Moscow (Russian Federation); Vakhrusheva, Tatyana V. [Research Institute for Physico-Chemical Medicine, Federal Medico-Biological Agency, Moscow (Russian Federation); Sokolov, Alexey V.; Kostevich, Valeria A. [Research Institute for Physico-Chemical Medicine, Federal Medico-Biological Agency, Moscow (Russian Federation); Research Institute for Experimental Medicine, Russian Academy of Medical Science, Saint Petersburg (Russian Federation); Gusev, Alexandr A.; Gusev, Sergey A. [Research Institute for Physico-Chemical Medicine, Federal Medico-Biological Agency, Moscow (Russian Federation); Melnikova, Viktoriya I. [Institute of Developmental Biology, Russian Academy of Science, Moscow (Russian Federation); Lobach, Anatolii S. [Institute of Problems of Chemical Physics, Russian Academy of Science, Chernogolovka (Russian Federation)

    2012-10-01

    Perspectives for the use of carbon nanotubes in biomedical applications depend largely on their ability to degrade in the body into products that can be easily cleared out. Carboxylated single-walled carbon nanotubes (c-SWCNTs) were shown to be degraded by oxidants generated by peroxidases in the presence of hydrogen peroxide. In the present study we demonstrated that conjugation of poly(ethylene glycol) (PEG) to c-SWCNTs does not interfere with their degradation by peroxidase/H{sub 2}O{sub 2} system or by hypochlorite. Comparison of different heme-containing proteins for their ability to degrade PEG-SWCNTs has led us to conclude that the myeloperoxidase (MPO) product hypochlorous acid (HOCl) is the major oxidant that may be responsible for biodegradation of PEG-SWCNTs in vivo. MPO is secreted mainly by neutrophils upon activation. We hypothesize that SWCNTs may enhance neutrophil activation and therefore stimulate their own biodegradation due to MPO-generated HOCl. PEG-SWCNTs at concentrations similar to those commonly used in in vivo studies were found to activate isolated human neutrophils to produce HOCl. Both PEG-SWCNTs and c-SWCNTs enhanced HOCl generation from isolated neutrophils upon serum-opsonized zymosan stimulation. Both types of nanotubes were also found to activate neutrophils in whole blood samples. Intraperitoneal injection of a low dose of PEG-SWCNTs into mice induced an increase in percentage of circulating neutrophils and activation of neutrophils and macrophages in the peritoneal cavity, suggesting the evolution of an inflammatory response. Activated neutrophils can produce high local concentrations of HOCl, thereby creating the conditions favorable for degradation of the nanotubes. -- Highlights: ► Myeloperoxidase (MPO) product hypochlorous acid is able to degrade CNTs. ► PEGylated SWCNTs stimulate isolated neutrophils to produce hypochlorous acid. ► SWCNTs are capable of activating neutrophils in blood samples. ► Activation of

  6. Superoxide anion production by human neutrophils activated by Trichomonas vaginalis.

    Science.gov (United States)

    Song, Hyun-Ouk; Ryu, Jae-Sook

    2013-08-01

    Neutrophils are the predominant inflammatory cells found in vaginal discharges of patients infected with Trichomonas vaginalis. In this study, we examined superoxide anion (O2 (.-)) production by neutrophils activated by T. vaginalis. Human neutrophils produced superoxide anions when stimulated with either a lysate of T. vaginalis, its membrane component (MC), or excretory-secretory product (ESP). To assess the role of trichomonad protease in production of superoxide anions by neutrophils, T. vaginalis lysate, ESP, and MC were each pretreated with a protease inhibitor cocktail before incubation with neutrophils. Superoxide anion production was significantly decreased by this treatment. Trichomonad growth was inhibited by preincubation with supernatants of neutrophils incubated for 3 hr with T. vaginalis lysate. Furthermore, myeloperoxidase (MPO) production by neutrophils was stimulated by live trichomonads. These results indicate that the production of superoxide anions and MPO by neutrophils stimulated with T. vaginalis may be a part of defense mechanisms of neutrophils in trichomoniasis.

  7. Neutrophils in Cancer: Two Sides of the Same Coin

    Directory of Open Access Journals (Sweden)

    Eileen Uribe-Querol

    2015-01-01

    Full Text Available Neutrophils are the most abundant leukocytes in blood and are considered to be the first line of defense during inflammation and infections. In addition, neutrophils are also found infiltrating many types of tumors. Tumor-associated neutrophils (TANs have relevant roles in malignant disease. Indeed neutrophils may be potent antitumor effector cells. However, increasing clinical evidence shows TANs correlate with poor prognosis. The tumor microenvironment controls neutrophil recruitment and in turn TANs help tumor progression. Hence, TANs can be beneficial or detrimental to the host. It is the purpose of this review to highlight these two sides of the neutrophil coin in cancer and to describe recent studies that provide some light on the mechanisms for neutrophil recruitment to the tumor, for neutrophils supporting tumor progression, and for neutrophil activation to enhance their antitumor functions.

  8. The natural stilbenoid pinosylvin and activated neutrophils: effects on oxidative burst, protein kinase C, apoptosis and efficiency in adjuvant arthritis

    Institute of Scientific and Technical Information of China (English)

    Viera JAN(C)INOV(A); Tomá(s) PERE(C)KO; Rado NOS(A)(L); Juraj HARMATHA; Jan (S)MIDRKAL; Katarína DR(A)BIKOV(A)

    2012-01-01

    Aim:To investigate the effects of the naturally occurring stilbenoid pinosylvin on neutrophil activity in vitro and in experimental arthritis,and to examine whether protein kinase C (PKC) activation served as an assumed target of pinosylvin action.Methods:Fresh human blood neutrophils were isolated.The oxidative burst of neutrophils was evaluated on the basis of enhanced chemiluminescence.Neutrophil viability was evaluated with flow cytometry,and PKC phosphorylation was assessed by Western blotting analysis.Adjuvant arthritis was induced in Lewis rats with heat-killed Mycobacterium butyricum,and the animals were administered with pinosylvin (30 mg/kg,po) daily for 21 d after arthritis induction.Results:In isolated human neutrophils,pinosylvin (10 and 100 μmol/L) significantly decreased the formation of oxidants,both extraand intracellularly,and effectively inhibited PKC activation stimulated by phorbol myristate acetate (0.05 μmol/L).The inhibition was not due to neutrophil damage or increased apoptosis.In arthritic rats,the number of neutrophils in blood was dramatically increased,and whole blood chemiluminescence (spontaneous and PMA-stimulated) was markedly enhanced.Pinosylvin administration decreased the number of neutrophils (from 69 671±5588/μL to 51 293±3947/μL,P=0.0198) and significantly reduced the amount of reactive oxygen species in blood.Conclusion:Pinosylvin is an effective inhibitor of neutrophil activity,and is potentially useful as a complementary medicine in states associated with persistent inflammation.

  9. Cereral Circulation in Preeclampsia

    Directory of Open Access Journals (Sweden)

    A. A. Ivshin

    2008-01-01

    Full Text Available Objective: to evaluate the possibilities of using transcranial Doppler study in pregnant women and pueperas with preeclamp-sia. Subjects and methods. Two hundred and thirty-two pregnant women diagnosed as having varying preeclampsia were prospectively studied. A comparison group comprised 90 apparently healthy women in the third trimester of pregnancy. All the respondents underwent transcranial duplex scanning of the medial cerebral artery with the linear velocity values being determined. A number of the values reflecting the level of perfusion and intracranial pressures, hydrodynamic resistance in the system, cerebrovascular responsiveness and the state of the vascular wall were calculated. Correlation analysis was made between the parameters of cerebral circulation and the severity of preeclampsia, proteinuria, the severity of hydrops, and the parameters of central and peripheral hemodynamics. Results. The findings suggest that there is impaired cerebral perfusion in pregnant women and puerperas with varying preeclampsia, the severity of cerebral circulatory disorders being in proportion with that of preeclampsia. There is a close correlation between cerebral circulation and the individual criteria determining the severity of preeclampsia. The linear values of the Doppler spectrum, namely linear flow characteristics, are prognos-tically most significant. Conclusion. The introduction of transcranial Doppler study into obstetric care has permitted the authors not only to study cerebral circulatory disorders in healthy and pregnant women and puerperas with preeclampia in detail, but also to establish a number of highly significant prognostic criteria for the severity of this life-threatening complication of gestation. The results of transcranial Doppler study assist practitioners in timely and accurately solving the problems in the diagnosis of preeclampsia and in evaluating its severity. Cerebral circulatory values may be successfully used to

  10. Dihydroxyoctadecamonoenoate esters inhibit the neutrophil respiratory burst

    Indian Academy of Sciences (India)

    David Alan Thompson; Bruce D Hammock

    2007-03-01

    The leukotoxins [9(10)- and 12(13)-EpOME] are produced by activated inflammatory leukocytes such as neutrophils. High EpOME levels are observed in disorders such as acute respiratory distress syndrome and in patients with extensive burns. Although the physiological significance of the EpOMEs remains poorly understood, in some systems, the EpOMEs act as a protoxin, with their corresponding epoxide hydrolase metabolites, 9,10- and 12,13-DiHOME, specifically exerting toxicity. Both the EpOMEs and the DiHOMEs were also recently shown to have neutrophil chemotactic activity. We evaluated whether the neutrophil respiratory burst, a surge of oxidant production thought to play an important role in limiting certain bacterial and fungal infections, is modulated by members of the EpOME metabolic pathway. We present evidence that the DiHOMEs suppress the neutrophil respiratory burst by a mechanism distinct from that of respiratory burst inhibitors such as cyclosporin H or lipoxin A4, which inhibit multiple aspects of neutrophil activation.

  11. Genetic and pharmacological inhibition of CDK9 drives neutrophil apoptosis to resolve inflammation in zebrafish in vivo

    Science.gov (United States)

    Hoodless, Laura J.; Lucas, Christopher D.; Duffin, Rodger; Denvir, Martin A.; Haslett, Christopher; Tucker, Carl S.; Rossi, Adriano G.

    2016-01-01

    Neutrophilic inflammation is tightly regulated and subsequently resolves to limit tissue damage and promote repair. When the timely resolution of inflammation is dysregulated, tissue damage and disease results. One key control mechanism is neutrophil apoptosis, followed by apoptotic cell clearance by phagocytes such as macrophages. Cyclin-dependent kinase (CDK) inhibitor drugs induce neutrophil apoptosis in vitro and promote resolution of inflammation in rodent models. Here we present the first in vivo evidence, using pharmacological and genetic approaches, that CDK9 is involved in the resolution of neutrophil-dependent inflammation. Using live cell imaging in zebrafish with labelled neutrophils and macrophages, we show that pharmacological inhibition, morpholino-mediated knockdown and CRISPR/cas9-mediated knockout of CDK9 enhances inflammation resolution by reducing neutrophil numbers via induction of apoptosis after tailfin injury. Importantly, knockdown of the negative regulator La-related protein 7 (LaRP7) increased neutrophilic inflammation. Our data show that CDK9 is a possible target for controlling resolution of inflammation. PMID:27833165

  12. Autoimmunity-related neutrophilic dermatosis: a newly described entity that is not exclusive of systemic lupus erythematosus.

    Science.gov (United States)

    Saeb-Lima, Marcela; Charli-Joseph, Yann; Rodríguez-Acosta, Elva Dalia; Domínguez-Cherit, Judith

    2013-08-01

    Neutrophilic dermatoses have long been known to be associated with autoinmune systemic diseases. Recently, a small number of cases of a disorder distinct from Sweet syndrome or bullous lupus erythematosus (LE) have been described as specifically related to systemic LE under diverse terms, including nonbullous neutrophilic dermatosis, nonbullous neutrophilic LE, and Sweet-like neutrophilic dermatosis. We describe 7 patients that developed urticarial lesions in the context of a known or concurrently diagnosed autoimmune connective tissue disease. Of a total of 7 patients, 6 were afflicted by systemic LE and 1 by rheumatoid arthritis and secondary Sjögren syndrome. Histological findings in all patients included an interstitial and perivascular neutrophilic infiltrate with leukocytoclasia, vacuolar alteration along the dermal-edidermal junction, and no vasculitis. Most patients had active systemic disease at the time of the cutaneous eruption. Skin lesions resolved rapidly after the administration of immunomodulating agents. In conclusion, we provide additional evidence of the existence of a recently defined nonbullous neutrophilic dermatosis in the context of autoimmune connective tissue diseases and propose the term autoimmunity-related neutrophilic dermatosis as an appropriate designation. Furthermore, we believe that this entity should prompt physicians to screen the presence of an active systemic disorder in afflicted patients.

  13. Neutrophil-delivered myeloperoxidase dampens the hydrogen peroxide burst after tissue wounding in zebrafish.

    Science.gov (United States)

    Pase, Luke; Layton, Judith E; Wittmann, Christine; Ellett, Felix; Nowell, Cameron J; Reyes-Aldasoro, Constantino Carlos; Varma, Sony; Rogers, Kelly L; Hall, Chris J; Keightley, M Cristina; Crosier, Philip S; Grabher, Clemens; Heath, Joan K; Renshaw, Stephen A; Lieschke, Graham J

    2012-10-09

    Prompt neutrophil arrival is critical for host defense immediately after injury [1-3]. Following wounding, a hydrogen peroxide (H(2)O(2)) burst generated in injured tissues is the earliest known leukocyte chemoattractant [4]. Generating this tissue-scale H(2)O(2) gradient uses dual oxidase [4] and neutrophils sense H(2)O(2) by a mechanism involving the LYN Src-family kinase [5], but the molecular mechanisms responsible for H(2)O(2) clearance are unknown [6]. Neutrophils carry abundant amounts of myeloperoxidase, an enzyme catalyzing an H(2)O(2)-consuming reaction [7, 8]. We hypothesized that this neutrophil-delivered myeloperoxidase downregulates the high tissue H(2)O(2) concentrations that follow wounding. This was tested in zebrafish using simultaneous fluorophore-based imaging of H(2)O(2) concentrations and leukocytes [4, 9-11] and a new neutrophil-replete but myeloperoxidase-deficient mutant (durif). Leukocyte-depleted zebrafish had an abnormally sustained wound H(2)O(2) burst, indicating that leukocytes themselves were required for H(2)O(2) downregulation. Myeloperoxidase-deficient zebrafish also had abnormally sustained high wound H(2)O(2) concentrations despite similar numbers of arriving neutrophils. A local H(2)O(2)/myeloperoxidase interaction within wound-recruited neutrophils was demonstrated. These data demonstrate that leukocyte-delivered myeloperoxidase cell-autonomously downregulates tissue-generated wound H(2)O(2) gradients in vivo, defining a new requirement for myeloperoxidase during inflammation. Durif provides a new animal model of myeloperoxidase deficiency closely phenocopying the prevalent human disorder [7, 12, 13], offering unique possibilities for investigating its clinical consequences.

  14. hMSCs suppress neutrophil-dominant airway inflammation in a murine model of asthma

    Science.gov (United States)

    Hong, Gyong Hwa; Kwon, Hyouk-Soo; Lee, Kyoung Young; Ha, Eun Hee; Moon, Keun-Ai; Kim, Seong Who; Oh, Wonil; Kim, Tae-Bum; Moon, Hee-Bom; Cho, You Sook

    2017-01-01

    Although chronic eosinophilic inflammation is a common feature in patients with asthma, some patients have neutrophil-dominant inflammation, which is known to be associated with severe asthma.Human mesenchymal stem cells (hMSCs) have shown promise in treating various refractory immunological diseases. Thus, hMSCs may represent an alternative therapeutic option for asthma patients with neutrophil-dominant inflammation, in whom current treatments are ineffective. BALB/c mice exposed to ovalbumin and polyinosinic:polycytidylic acid (Poly I:C) to induce neutrophilic airway inflammation were systemically treated with hMSCs to examine whether the hMSCs can modulate neutrophilic airway inflammation. In addition, cytokine production was evaluated in co-cultures of hMSCs with either anti-CD3/CD28-stimulated peripheral blood mononuclear cells (PBMCs) obtained from asthmatic patients or cells of the human bronchial epithelial cell line BEAS-2B to assess the response to hMSC treatment. The total number of immune cells in bronchoalveolar lavage fluid (BALF) showed a dramatic decrease in hMSC-treated asthmatic mice, and, in particular, neutrophilic infiltration was significantly attenuated. This phenomenon was accompanied by reduced CXCL15 production in the BALF. BEAS-2B cells co-cultured with hMSCs showed reduced secretion of IL-8. Moreover, decreased secretion of IL-4, IL-13 and IFN-γ was observed when human PBMCs were cultured with hMSCs, whereas IL-10 production was greatly enhanced. Our data imply that hMSCs may have a role in reducing neutrophilic airway inflammation by downregulating neutrophil chemokine production and modulating T-cell responses. PMID:28127050

  15. The Inhibitory Effect of Quercetin on IL-6 Production by LPS-Stimulated Neutrophils

    Institute of Scientific and Technical Information of China (English)

    Jiajia Liu; Xin Li; Yang Yue; Juan Li; Tao He; Yanzheng He

    2005-01-01

    Quercetin is a herbal flavonoid derived from various foods of plant origin and plays a role in anti-inflammation. Although a number of researches in the field have been done, the mechanism of anti-inflammatory effect of quercetin should be further clarified. In the present study, we investigated the effects of quercetin on IL-6 production by LPS-stimulated neutrophils in human. Neutrophils were were pre-treated with quercetin at the final concentrations of ranging from 0-80 μM for 30 min, or not treated, and then incubated in the presence or absence of lipopolysaccharide (LPS) at a final concentration of 100 ng/ml for indicated time. The secretion level of IL-6 in the culture supernatants was assayed by ELISA, the intracellular level of IL-6 was detected by flow cytometry and the expression of IL-6 mRNA was analyzed by RT-PCR. The experiment results showed that neutrophils cultured with medium or quercetin alone did not express IL-6, but LPS (100 ng/ml) induced IL-6 expression of neutrophils. However, after pre-treatment of neutrophils with quercetin (40 μM) for 30 min, the inducible effects of LPS on the increase of IL-6 secretion, intracellular IL-6 level and IL-6 mRNA expression by neutrophils were abrogated. IL-6 is one of the important pro-inflammatory factors, especially in early phage of inflammation. Thus, our data suggested that quercetin might exert its anti-inflammatory effect through negatively modulating pro-inflammatory factors, such as IL-6. The inhibitory effects of quercetin on IL-6 production by neutrophils may provide a theoretical basis on future therapy of inflammation.

  16. CXCL8((3-73))K11R/G31P antagonizes the neutrophil chemoattractants present in pasteurellosis and mastitis lesions and abrogates neutrophil influx into intradermal endotoxin challenge sites in vivo.

    Science.gov (United States)

    Li, Fang; Zhang, Xiaobei; Mizzi, Chris; Gordon, John R

    2002-11-01

    The ELR(+) CXC chemokines are critical for protective neutrophil responses to most bacterial infections, but nevertheless can contribute importantly to the pathogenic effects of many inflammatory responses. We recently engineered a series of high affinity CXCL8/IL-8 antagonists, one of which, CXCL8((3-73))K11R/G31P, binds very strongly to neutrophils via the CXCR1 and CXCR2. Herein we show in competitive 125I-ligand binding assays that bovine CXCL8((3-73))K11R/G31P has an affinity for neutrophils that is 2-3 orders of magnitude higher than that of CXCL8/IL-8. Furthermore, when used at approximately 0.5 nM, CXCL8((3-73))K11R/G31P inhibited by 50% the chemotactic responses of neutrophils to 129 nM CXCL8/IL-8, but it also blocked chemotactic responses to the alternate ELR-CXC chemokines CXCL1/GRO alpha and CXCL5/ENA-78. Furthermore, CXCL8((3-73))K11R/G31P could inhibit by 93-97% the spectrum of neutrophil chemotactic activities present within wash fluids from clinical bacterial pneumonia or experimental endotoxin-induced mastitis lesions. Finally, intramuscular or subcutaneous application of CXCL8((3-73))K11R/G31P (75 micro g/kg) reduced by up to 97% neutrophil infiltration into intradermal endotoxin challenge sites in cattle, and prevented their circulating neutrophils from responding to CXCL8/IL-8 or ENA-78 in vitro. This data thus encourages further investigation of the potential impact of this novel antagonist on ELR-CXC chemokine-driven inflammatory disorders.

  17. Resolvability in Circulant Graphs

    Institute of Scientific and Technical Information of China (English)

    Muhammad SALMAN; Imran JAVAID; Muhammad Anwar CHAUDHRY

    2012-01-01

    A set W of the vertices of a connected graph G is called a resolving set for G if for every two distinct vertices u,v ∈ V(G) there is a vertex w ∈ W such that d(u,w) ≠ d(v,w).A resolving set of minimum cardinality is called a metric basis for G and the number of vertices in a metric basis is called the metric dimension of G,denoted by dim(G).For a vertex u of G and a subset S of V(G),the distance between u and S is the number mins∈s d(u,s).A k-partition H ={S1,S2,...,Sk} of V(G) is called a resolving partition if for every two distinct vertices u,v ∈ V(G) there is a set Si in Π such that d(u,Si) ≠ d(v,Si).The minimum k for which there is a resolving k-partition of V(G) is called the partition dimension of G,denoted by pd(G).The circulant graph is a graph with vertex set Zn,an additive group ofintegers modulo n,and two vertices labeled i and j adjacent if and only if i - j (mod n) ∈ C,where C C Zn has the property that C =-C and 0(∈) C.The circulant graph is denoted by Xn,△ where A =|C|.In this paper,we study the metric dimension of a family of circulant graphs Xn,3 with connection set C ={1,-n/2,n - 1} and prove that dim(Xn,3) is independent of choice of n by showing that 3 for all n =0 (mod 4),dim(X,n,3) ={ 4 for all n =2 (mod 4).We also study the partition dimension of a family of circulant graphs Xn,4 with connection set C ={±1,±2} and prove that pd(Xn,4) is independent of choice of n and show that pd(X5,4) =5 and 3 forall odd n≥9,pd(Xn,4) ={ 4 for all even n ≥ 6 and n =7.

  18. Granulopoiesis and granules of human neutrophils

    DEFF Research Database (Denmark)

    Cowland, Jack B; Borregaard, Niels

    2016-01-01

    Granules are essential for the ability of neutrophils to fulfill their role in innate immunity. Granule membranes contain proteins that react to environmental cues directing neutrophils to sites of infection and initiate generation of bactericidal oxygen species. Granules are densely packed...... with proteins that contribute to microbial killing when liberated to the phagosome or extracellularly. Granules are, however, highly heterogeneous and are traditionally subdivided into azurophil granules, specific granules, and gelatinase granules in addition to secretory vesicles. This review will address...... issues pertinent to formation of granules, which is a process intimately connected to maturation of neutrophils from their precursors in the bone marrow. We further discuss possible mechanisms by which decisions are made regarding sorting of proteins to constitutive secretion or storage in granules...

  19. Clinical microfluidics for neutrophil genomics and proteomics.

    Science.gov (United States)

    Kotz, Kenneth T; Xiao, Wenzong; Miller-Graziano, Carol; Qian, Wei-Jun; Russom, Aman; Warner, Elizabeth A; Moldawer, Lyle L; De, Asit; Bankey, Paul E; Petritis, Brianne O; Camp, David G; Rosenbach, Alan E; Goverman, Jeremy; Fagan, Shawn P; Brownstein, Bernard H; Irimia, Daniel; Xu, Weihong; Wilhelmy, Julie; Mindrinos, Michael N; Smith, Richard D; Davis, Ronald W; Tompkins, Ronald G; Toner, Mehmet

    2010-09-01

    Neutrophils have key roles in modulating the immune response. We present a robust methodology for rapidly isolating neutrophils directly from whole blood with 'on-chip' processing for mRNA and protein isolation for genomics and proteomics. We validate this device with an ex vivo stimulation experiment and by comparison with standard bulk isolation methodologies. Last, we implement this tool as part of a near-patient blood processing system within a multi-center clinical study of the immune response to severe trauma and burn injury. The preliminary results from a small cohort of subjects in our study and healthy controls show a unique time-dependent gene expression pattern clearly demonstrating the ability of this tool to discriminate temporal transcriptional events of neutrophils within a clinical setting.

  20. GM-CSF and TNF alpha modulate protein expression of human neutrophils visualized by fluorescence two-dimensional difference gel electrophoresis

    NARCIS (Netherlands)

    Langereis, Jeroen D.; Franciosi, Lorenza; Ulfman, Laurien H.; Koenderman, Leo

    2011-01-01

    Increased serum levels of TNF alpha and GM-CSF are found in various chronic inflammatory diseases and these cytokines affect the function of circulating and tissue neutrophils. TNF alpha- and GM-CSF-induced protein expression profiles could, therefore, serve as biomarker for the action of these cyto

  1. [Ultrastructural location of enzymes in peripheral blood neutrophils and in cerebrospinal fluid neutrophils in neuroinfections].

    Science.gov (United States)

    Skotarczak, B

    1993-01-01

    Using cytochemical methods the location and activity were determined of alkaline phosphatase, ATP-ase and succinate dehydrogenase as representative enzymes for the metabolic processes in neutrophils isolated from blood and cerebrospinal fluid (CSF) of patients with meningococcal meningoencephalitis as compared with peripheral blood neutrophils in a control group. The study showed presence of phosphatase on the membranes of many intracellular structures. The activity of the enzymes was higher than in the control group in the membranes of neutrophils in blood and CSF. This is explained as an effect of action of the chemotactic factor on the cell membrane and activation of the cell to movements and phagocytosis. ATP-ase activity in peripheral blood neutrophils in controls was found in all membranous structures in the cell. However, in peripheral blood neutrophils and CSF neutrophils in the acute stage of the disease the active enzyme was noted, in the first place, in cell membranes and digesting vacuoles, which reflected probably the direction of metabolic processes for phagocytosis and destroying of bacteria. The activity of succinate dehydrogenase was found in mitochondrial membranes. Peripheral blood and CSF neutrophils showed a high activity of the enzyme. In the CSF cells in acute phase atypical sites of succinate dehydrogenase activity were noted, which was explained as a sign of cell destruction.

  2. Quantitative proteomics reveals differential biological processes in healthy neonatal cord neutrophils and adult neutrophils

    KAUST Repository

    Zhu, Jiang

    2014-06-11

    Neonatal neutrophils are characterized by the immaturity of bactericidal mechanisms that contributes largely to neonatal mortality. However, underlying molecular mechanism associated with the immaturity remains incompletely understood. In this study, we performed comparative proteomic analysis on neonatal neutrophils derived from human cord blood and adult peripheral neutrophils. A total of 1332 proteins were identified and quantified, and 127 proteins were characterized as differentially expressed between adult and cord neutrophils. The differentially expressed proteins are mapped in KEGG pathways into five clusters and indicated impaired functions of neonatal neutrophils in proteasome, lysosome, phagosome, and leukocyte transendothelial migration. In particular, many proteins associated with NETosis, a critical mechanism for antimicrobial process and auto-clearance, were also found to be downregulated in cord neutrophils. This study represents a first comparative proteome profiling of neonatal and adult neutrophils, and provides a global view of differentially expressed proteome for enhancing our understanding of their various functional difference. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Attachment and ingestion of gonococci human neutrophils.

    Science.gov (United States)

    Dilworth, J A; Hendley, J O; Mandell, G L

    1975-03-01

    Previous studies have indirectly shown that type 1 gonococci are more resistant to phagocytosis by human neutrophils (PMN) than type 3 gonococci. Using phase contrast, fluorescent, and light microscopy, we directly quantitated PMN-gonococcal interaction, with emphasis on separating ingestion from attachment. PMN monolayers were incubated on slides with type 1 or type 3 gonococcal fluorescent antibody (FA). After methanol fixation, the FA-stained gonococci associated with PMN were cointed. Since the live PMN excludes FA, the FA-stained gonococci represent only extracellular gonococci. Methylene blue was then added to the smae slide to stain both ingested and surface attached gonococci. Using these methods, intracellular and extracellular cell-associated gonococci were quantitated under varying conditions. The numbers of methylene blue-stained cell-associated gonococci that were ingested were: with normal serum, 3.7 plus or minus 4.1 per cent for type 1 and 56.2 plus or minus 3.7 percent for type 3 (P smaller than 0.001); with heat-inactivated serum, 1.0 plus or minus 3.0 per cent for type 1 and 52.6 plus or minus 3.7 per cent for type 3 (P smaller than 0.001); with higher-titer anti-gonococcal antibody serum, 4.8 plus or minus 4.3 percent for type 1 and 64.0 plus or minus 1.6 per cent for type 3 (P smaller than 0.001). Thus, most type 3 organisms were ingested, but most type 1 gonococci were bound on the PMN surface.

  4. Metabolic requirements for neutrophil extracellular traps formation

    Science.gov (United States)

    Rodríguez-Espinosa, Oscar; Rojas-Espinosa, Oscar; Moreno-Altamirano, María Maximina Bertha; López-Villegas, Edgar Oliver; Sánchez-García, Francisco Javier

    2015-01-01

    As part of the innate immune response, neutrophils are at the forefront of defence against infection, resolution of inflammation and wound healing. They are the most abundant leucocytes in the peripheral blood, have a short lifespan and an estimated turnover of 1010 to 1011 cells per day. Neutrophils efficiently clear microbial infections by phagocytosis and by oxygen-dependent and oxygen-independent mechanisms. In 2004, a new neutrophil anti-microbial mechanism was described, the release of neutrophil extracellular traps (NETs) composed of DNA, histones and anti-microbial peptides. Several microorganisms, bacterial products, as well as pharmacological stimuli such as PMA, were shown to induce NETs. Neutrophils contain relatively few mitochondria, and derive most of their energy from glycolysis. In this scenario we aimed to analyse some of the metabolic requirements for NET formation. Here it is shown that NETs formation is strictly dependent on glucose and to a lesser extent on glutamine, that Glut-1, glucose uptake, and glycolysis rate increase upon PMA stimulation, and that NET formation is inhibited by the glycolysis inhibitor, 2-deoxy-glucose, and to a lesser extent by the ATP synthase inhibitor oligomycin. Moreover, when neutrophils were exposed to PMA in glucose-free medium for 3 hr, they lost their characteristic polymorphic nuclei but did not release NETs. However, if glucose (but not pyruvate) was added at this time, NET release took place within minutes, suggesting that NET formation could be metabolically divided into two phases; the first, independent from exogenous glucose (chromatin decondensation) and, the second (NET release), strictly dependent on exogenous glucose and glycolysis. PMID:25545227

  5. Differential activation of RAGE by HMGB1 modulates neutrophil-associated NADPH oxidase activity and bacterial killing.

    Science.gov (United States)

    Tadié, Jean-Marc; Bae, Hong-Beom; Banerjee, Sami; Zmijewski, Jaroslaw W; Abraham, Edward

    2012-01-01

    The receptor for advanced glycation end products (RAGE) plays an important role in host defense against bacterial infection. In the present experiments, we investigated the mechanisms by which RAGE contributes to the ability of neutrophils to eradicate bacteria. Wild-type (RAGE(+/+)) neutrophils demonstrated significantly greater ability to kill Escherichia coli compared with RAGE(-/-) neutrophils. After intraperitoneal injection of E. coli, increased numbers of bacteria were found in the peritoneal fluid from RAGE(-/-) as compared with RAGE(+/+) mice. Exposure of neutrophils to the protypical RAGE ligand AGE resulted in activation of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase and enhanced killing of E. coli, and intraperitoneal injection of AGE enhanced bacterial clearance during peritonitis. However, incubation of neutrophils with high mobility group box 1 protein (HMGB1), which also binds to RAGE, diminished E. coli-induced activation of NADPH oxidase in neutrophils and bacterial killing both in vitro and in vivo. Deletion of the COOH-terminal tail of HMGB1, a region necessary for binding to RAGE, abrogated the ability of HMGB1 to inhibit bacterial killing. Incubation of neutrophils with HMGB1 diminished bacterial or AGE-dependent activation of NADPH oxidase. The increase in phosphorylation of the p40(phox) subunit of NADPH oxidase that occurred after culture of neutrophils with E. coli was inhibited by exposure of the cells to HMGB1. These results showing that HMGB1, through RAGE-dependent mechanisms, diminishes bacterial killing by neutrophils as well as NADPH oxidase activation provide a novel mechanism by which HMGB1 can potentiate sepsis-associated organ dysfunction and mortality.

  6. Crucial involvement of tumor-associated neutrophils in the regulation of chronic colitis-associated carcinogenesis in mice.

    Directory of Open Access Journals (Sweden)

    Kun Shang

    Full Text Available Ulcerative colitis (UC is a major form of chronic inflammation that can frequently progress to colon cancer. Several studies have demonstrated massive infiltration of neutrophils and macrophages into the lamina propria and submucosa in the progression of UC-associated colon carcinogenesis. Macrophages contribute to the development of colitis-associated colon cancer (CAC. However, the role of neutrophils is not well understood. To better understand the involvement of tumor-associated neutrophils (TANs in the regulation of CAC, we used a mouse CAC model produced by administering azoxymethane (AOM, followed by repeated dextran sulfate sodium (DSS ingestion. This causes severe colonic inflammation and subsequent development of multiple tumors in mice colon. We observed that colorectal mucosal inflammation became increasingly severe with AOM and DSS treatment. Macrophages infiltrated the lamina propria and submucosa, together with a marked increase in neutrophil infiltration. The chemokine CXCL2 increased in the lamina propria and submucosal regions of the colons of the treated mice, together with the infiltration of neutrophils expressing CXCR2, a specific receptor for CXCL2. This process was followed by neoplastic transformation. After AOM and DSS treatment, the mice showed enhanced production of metalloproteinase (MMP-9 and neutrophil elastase (NE, accompanied by excessive vessel generation and cell proliferation. Moreover, CXCL2 promoted neutrophil recruitment and induced neutrophils to express MMP-9 and NE in vitro. Furthermore, administration of neutrophil-neutralizing antibodies after the last DSS cycle markedly reduced the number and size of tumors and decreased the expression of CXCR2, CXCL2, MMP-9, and NE. These observations indicate a crucial role for TANs in the initiation and progression of CAC and suggest that the CXCL2-CXCR2 axis might be useful in reducing the risk of UC-associated colon cancer.

  7. Anti-neutrophil cytoplasm autoantibodies (ANCA) in autoimmune liver diseases

    NARCIS (Netherlands)

    Roozendaal, C.; Kallenberg, Cees

    1999-01-01

    Anti-neutrophil cytoplasm antibodies (ANCA) are autoantibodies directed against cytoplasmic constituents of neutrophil granulocytes and monocytes. ANCA have been detected in serum from patients with inflammatory bowel diseases (mainly ulcerative colitis) and autoimmune mediated liver diseases (mainl

  8. Primed neutrophil infiltrations into multiple organs in child physical abuse cases: A preliminary study.

    Science.gov (United States)

    Hayashi, Takahito; Nakamae, Takuma; Higo, Eri; Ikematsu, Kazuya; Ogata, Mamoru

    2017-01-01

    Physical abuse of the elderly induces a massive primed neutrophil infiltration into the lung and liver through chemotaxis by interleukin (IL)-8, similar to cases of traumatic or hemorrhagic shock. Here, we used immunohistochemical analyses to investigate this infiltration in cases of physically abused children. In addition, we examined the expression of neutrophil elastase (NE) as the inflammatory mediator and α1-antitrypsin (AAT) as the elastase inhibitor. The number of neutrophils in the abuse cases was increased significantly in the heart, lung, liver, and kidney, compared with that of control cases. IL-8-positive cells and NE-positive cells in all organs of abuse cases were significantly greater than those in control cases. Large quantities of oxidized AAT, which fails to inactivate NE and results in tissue damage, was detected in the liver of abuse cases. Neutrophil infiltration showed positive correlation with the degree of systemic accumulation of non-fatal injuries caused by repetitive abusive behavior. Although further investigation using more autopsy samples is necessary, results of our preliminary study indicate that massive neutrophil infiltration induced by IL-8 in multiple organs is a new complementary diagnostic indicator of physical abuse in children. Moreover, the demonstration of NE-positive cells and oxidized AAT provides firm evidence of tissue damage.

  9. A Morphological and Cytochemical Study of the Interaction between Paracoccidiodes brasiliensis and Neutrophils

    Science.gov (United States)

    Dias, Maria Fernanda R. G.; Filgueira, Absalom L.; de Souza, Wanderley

    2004-04-01

    Paracoccidioidomycosis is a systemic granulomatous disease caused by the dimorphic fungus Paracoccidioides brasiliensis. It is the most prevalent systemic mycosis of Latin America and 80% of the reported cases are from Brazil. Because of the great number of neutrophils found in the P. brasiliensis granuloma, studies have been done to evaluate the role of these cells during the development of the infection. Scanning and transmission electron microscopy of thin sections showed that the neutrophils ingest yeast cells through a typical phagocytic process with the formation of pseudopodes. The pseudopodes even disrupt the connection established between the mother and the bud cells. Neutrophils also associate to each other, forming a kind of extracellular vacuole where large yeast cells are encapsulated. Cytochemical studies showed that once P. brasiliensis attaches to the neutrophil surface, it triggers a respiratory burst with release of oxygen-derived products. Attachment also triggers neutrophils' degranulation, with release of endogenous peroxidase localized in cytoplasmic granules. Together, these processes lead to killing of both ingested and extracellular P. brasiliensis.

  10. Analysis of Ascorbic Acid in Single Human Neutrophils by Electrochemical Detection

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Ascorbic acid in individual human neutrophils was determined by capillary zone electrophoresis with electrochemical detection. In order to overcome the influence of the adsorption of the substances in cells on the inner surface wall of the capillary on the migration time and the number of theoretical plates, a procedure for treating capillaries has been described.

  11. Aberrant “Barbed-Wire” Nuclear Projections of Neutrophils in Trisomy 18 (Edwards Syndrome

    Directory of Open Access Journals (Sweden)

    Basil M. Kahwash

    2015-01-01

    Full Text Available We discuss the significance of neutrophils with increased, aberrant nuclear projections mimicking “barbed-wire” in a newborn child with trisomy 18 (T18. Increased, aberrant nuclear projections have been previously reported in trisomy of the D group of chromosomes (chromosomes 13, 14, and 15, and we report similar findings in a patient with T18. The peripheral blood smear showed relative neutrophilia with the majority (37% of neutrophils showing two or more thin, rod-shaped or spike-shaped, and often pedunculated aberrant nuclear projections. The number of projections ranged from 2 to 6 per cell, averaged 2 per affected neutrophil, and ranged in length from 0.22 μm to 0.83 μm. This case confirms that the morphologic finding described is not restricted to trisomy of one of the chromosomes in group D, as implied in the literature.

  12. Aberrant "Barbed-Wire" Nuclear Projections of Neutrophils in Trisomy 18 (Edwards Syndrome).

    Science.gov (United States)

    Kahwash, Basil M; Nowacki, Nicholas B; Kahwash, Samir B

    2015-01-01

    We discuss the significance of neutrophils with increased, aberrant nuclear projections mimicking "barbed-wire" in a newborn child with trisomy 18 (T18). Increased, aberrant nuclear projections have been previously reported in trisomy of the D group of chromosomes (chromosomes 13, 14, and 15), and we report similar findings in a patient with T18. The peripheral blood smear showed relative neutrophilia with the majority (37%) of neutrophils showing two or more thin, rod-shaped or spike-shaped, and often pedunculated aberrant nuclear projections. The number of projections ranged from 2 to 6 per cell, averaged 2 per affected neutrophil, and ranged in length from 0.22 μm to 0.83 μm. This case confirms that the morphologic finding described is not restricted to trisomy of one of the chromosomes in group D, as implied in the literature.

  13. The Molecular Mechanisms of Glucocorticoids-Mediated Neutrophil Survival

    OpenAIRE

    2011-01-01

    Neutrophil-dominated inflammation plays an important role in many airway diseases including asthma, chronic obstructive pulmonary disease (COPD), bronchiolitis and cystic fibrosis. In cases of asthma where neutrophil-dominated inflammation is a major contributing factor to the disease, treatment with corticosteroids can be problematic as corticosteroids have been shown to promote neutrophil survival which, in turn, accentuates neutrophilic inflammation. In light of such cases, novel targeted ...

  14. Phagocytosis and Killing of Staphylococcus aureus by Human Neutrophils

    OpenAIRE

    Lu, Thea; Porter, Adeline R.; Kennedy, Adam D.; Kobayashi, Scott D.; Frank R DeLeo

    2014-01-01

    Neutrophils are essential for host defense against Staphylococcus aureus infections. Although significant progress has been made, our understanding of neutrophil interactions with S. aureus remains incomplete. To provide a more comprehensive view of this process, we investigated phagocytosis and killing of S. aureus by human neutrophils using varied assay conditions in vitro. A greater percentage of bacteria were internalized by adherent neutrophils compared to those in suspension, and unexpe...

  15. Yersinia pseudotuberculosis is resistant to killing by human neutrophils.

    Science.gov (United States)

    Laws, Thomas R; Davey, Martin S; Green, Christopher; Cooper, Ian A M; Titball, Richard W; Lukaszewski, Roman A

    2011-06-01

    The interaction between human neutrophils and the Gram negative gastrointestinal pathogen Yersinia pseudotuberculosis was investigated in vitro. Despite the wealth of data describing how Yersinia can affect the function of neutrophils, there are no published studies describing if neutrophil cells can affect the viability of Y. pseudotuberculosis. The wild-type IP32953 strain of Y. pseudotuberculosis was found to be resistant to killing by human neutrophils. Confocal examination and flow-cytometric analysis of this interaction revealed that bacteria were taken up.

  16. Neutrophil-induced injury of rat pulmonary alveolar epithelial cells.

    OpenAIRE

    Simon, R H; DeHart, P D; Todd, R F

    1986-01-01

    The damage to pulmonary alveolar epithelial cells that occurs in many inflammatory conditions is thought to be caused in part by phagocytic neutrophils. To investigate this process, we exposed monolayers of purified rat alveolar epithelial cells to stimulated human neutrophils and measured cytotoxicity using a 51Cr-release assay. We found that stimulated neutrophils killed epithelial cells by a process that did not require neutrophil-generated reactive oxygen metabolites. Pretreatment of neut...

  17. Determination of vascular endothelial growth factor (VEGF) in circulating blood: significance of VEGF in various leucocytes and platelets

    DEFF Research Database (Denmark)

    Werther, K; Christensen, Ib Jarle; Nielsen, Hans Jørgen

    2002-01-01

    . In corresponding blood samples, automated complete blood count was performed, and the number of each cell type was correlated to VEGF concentrations in plasma, serum and lysed whole blood. Finally, the impact of increasing clotting time on the release of VEGF to serum was analysed. RESULTS: Isolated neutrophils......AIM: The sources of increased vascular endothelial growth factor (VEGF) concentrations in peripheral blood from cancer patients are not known in detail. The aim of the present study was to evaluate correlations between the VEGF content in isolated leucocyte subpopulations and VEGF concentrations...... in plasma, serum and lysed whole blood. METHODS: In 51 colorectal cancer (CRC) patients, circulating T-lymphocytes, B-lymphocytes, monocytes, and granulocytes were isolated by means of immunomagnetic separation. Subsequently, the isolated cells were lysed and VEGF contents in the lysates were determined...

  18. Evaluation of altitude-appropriate reference ranges for neutrophils in diagnosis of sepsis in very low birth weight infants: A multicenter retrospective study

    Science.gov (United States)

    Yu, Jialin; Fan, Juan; He, Yu; Dong, Wenhui; Wang, Zhengli

    2017-01-01

    Background The circulating neutrophil count was commonly believed to be influenced by altitude. At present, neutrophil reference ranges (RRs) for very low birth weight (VLBW) neonates are only available from the sea level and from high altitude. This study aimed to construct RRs for neutrophils in VLBW infants in an intermediate-altitude area and assess its usefulness in evaluation for sepsis. Methods This was a multicenter retrospective study of 2173 VLBW infants admitted to 20 hospitals in Chongqing in southwest of China with altitude from 1000 to 2600 feet. The RRs for absolute total neutrophils (ATN), absolute total immature neutrophils (ATI), and immature: total neutrophil proportion were constructed based on “normal” neonates (unlikely infection). Values of neutrophil from septic and uninfected neonates were respectively assessed using the revised RRs and the previous Mouzinho’s and Schmutz’s RRs. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were compared using the McNemar’s test or χ2 test. Results The upper limits for ATN and ATI using the revised RRs were much higher than those using Mouzinho’s RRs, but lower than those using Schmutz’s RRs. The revised RRs and Mouzinho’s RRs had higher sensitivities than Schmutz’s RRs at 73–672 h. The revised RRs had a higher specificity than Mouzinho’s RRs at both 0–72 h and 73–672 h. The NPV for any abnormality in neutrophil values was high at both 0–72 h and 73–672 h irrespective of the RRs used. Conclusion Altitude-appropriate RRs for neutrophils is more suitable to guide the diagnosis and management of neonatal sepsis in VLBW infants. PMID:28182674

  19. Exposure to Leishmania braziliensis triggers neutrophil activation and apoptosis.

    Directory of Open Access Journals (Sweden)

    Sarah A C Falcão

    2015-03-01

    Full Text Available BACKGROUND: Neutrophils are the first line of defense against invading pathogens and are rapidly recruited to the sites of Leishmania inoculation. During Leishmania braziliensis infection, depletion of inflammatory cells significantly increases the parasite load whereas co-inoculation of neutrophils plus L. braziliensis had an opposite effect. Moreover, the co-culture of infected macrophages and neutrophils also induced parasite killing leading us to ask how neutrophils alone respond to an L. braziliensis exposure. Herein we focused on understanding the interaction between neutrophils and L. braziliensis, exploring cell activation and apoptotic fate. METHODS AND FINDINGS: Inoculation of serum-opsonized L. braziliensis promastigotes in mice induced neutrophil accumulation in vivo, peaking at 24 h. In vitro, exposure of thyoglycollate-elicited inflammatory or bone marrow neutrophils to L. braziliensis modulated the expression of surface molecules such as CD18 and CD62L, and induced the oxidative burst. Using mCherry-expressing L. braziliensis, we determined that such effects were mainly observed in infected and not in bystander cells. Neutrophil activation following contact with L. braziliensis was also confirmed by the release of TNF-α and neutrophil elastase. Lastly, neutrophils infected with L. braziliensis but not with L. major displayed markers of early apoptosis. CONCLUSIONS: We show that L. braziliensis induces neutrophil recruitment in vivo and that neutrophils exposed to the parasite in vitro respond through activation and release of inflammatory mediators. This outcome may impact on parasite elimination, particularly at the early stages of infection.

  20. Impairment of adenosine A3 receptor activity disrupts neutrophil migratory capacity and impacts innate immune function in vivo.

    Science.gov (United States)

    Butler, Matt; Sanmugalingam, Devika; Burton, Victoria J; Wilson, Tammy; Pearson, Ruth; Watson, Robert P; Smith, Philip; Parkinson, Scott J

    2012-12-01

    Adenosine possesses potent anti-inflammatory properties which are partly mediated by G(i) -coupled adenosine A3 receptors (A3Rs). A3R agonists have shown clinical benefit in a number of inflammatory conditions although some studies in A3R-deficient mice suggest a pro-inflammatory role. We hypothesised that, in addition to cell signalling effects, A3R compounds might inhibit neutrophil chemotaxis by disrupting the purinergic feedback loop controlling leukocyte migration. Human neutrophil activation triggered rapid upregulation of surface A3R expression which was disrupted by pre-treatment with either agonist (Cl-IB-MECA) or antagonist (MRS1220). Both compounds reduced migration velocity and neutrophil transmigration capacity without impacting the response to chemokines per se. Similar effects were observed in murine neutrophils, while cells from A3R-deficient mice displayed a constitutively impaired migratory phenotype indicating compound-induced desensitisation and genetic ablation had the same functional outcome. In a dextran sodium sulphate-induced colitis model, A3R-deficient mice exhibited reduced colon pathology and decreased tissue myeloperoxidase levels at day 8 - consistent with reduced neutrophil recruitment. However, A3R-deficient mice were unable to resolve the dextran sodium sulphate-induced inflammation and had elevated numbers of tissue-associated bacteria by day 21. Our data indicate that A3Rs play a role in neutrophil migration and disrupting this function has the potential to adversely affect innate immune responses.

  1. Restraint stress alters neutrophil and macrophage phenotypes during wound healing.

    Science.gov (United States)

    Tymen, Stéphanie D; Rojas, Isolde G; Zhou, Xiaofeng; Fang, Zong Juan; Zhao, Yan; Marucha, Phillip T

    2013-02-01

    Previous studies reported that stress delays wound healing, impairs bacterial clearance, and elevates the risk for opportunistic infection. Neutrophils and macrophages are responsible for the removal of bacteria present at the wound site. The appropriate recruitment and functions of these cells are necessary for efficient bacterial clearance. In our current study we found that restraint stress induced an excessive recruitment of neutrophils extending the inflammatory phase of healing, and the gene expression of neutrophil attracting chemokines MIP-2 and KC. However, restraint stress did not affect macrophage infiltration. Stress decreased the phagocytic abilities of phagocytic cells ex vivo, yet it did not affect superoxide production. The cell surface expression of adhesion molecules CD11b and TLR4 were decreased in peripheral blood monocytes in stressed mice. The phenotype of macrophages present at the wound site was also altered. Gene expression of markers of pro-inflammatory classically activated macrophages, CXCL10 and CCL5, were down-regulated; as were markers associated with wound healing macrophages, CCL22, IGF-1, RELMα; and the regulatory macrophage marker, chemokine CCL1. Restraint stress also induced up-regulation of IL10 gene expression. In summary, our study has shown that restraint stress suppresses the phenotype shift of the macrophage population, as compared to the changes observed during normal wound healing, while the number of macrophages remains constant. We also observed a general suppression of chemokine gene expression. Modulation of the macrophage phenotype could provide a new therapeutic approach in the treatment of wounds under stress conditions in the clinical setting.

  2. Circulating Fibronectin Controls Tumor Growth

    Directory of Open Access Journals (Sweden)

    Anja von Au

    2013-08-01

    Full Text Available Fibronectin is ubiquitously expressed in the extracellular matrix, and experimental evidence has shown that it modulates blood vessel formation. The relative contribution of local and circulating fibronectin to blood vessel formation in vivo remains unknown despite evidence for unexpected roles of circulating fibronectin in various diseases. Using transgenic mouse models, we established that circulating fibronectin facilitates the growth of bone metastases by enhancing blood vessel formation and maturation. This effect is more relevant than that of fibronectin produced by endothelial cells and pericytes, which only exert a small additive effect on vessel maturation. Circulating fibronectin enhances its local production in tumors through a positive feedback loop and increases the amount of vascular endothelial growth factor (VEGF retained in the matrix. Both fibronectin and VEGF then cooperate to stimulate blood vessel formation. Fibronectin content in the tumor correlates with the number of blood vessels and tumor growth in the mouse models. Consistent with these results, examination of three separate arrays from patients with breast and prostate cancers revealed that a high staining intensity for fibronectin in tumors is associated with increased mortality. These results establish that circulating fibronectin modulates blood vessel formation and tumor growth by modifying the amount of and the response to VEGF. Furthermore, determination of the fibronectin content can serve as a prognostic biomarker for breast and prostate cancers and possibly other cancers.

  3. Neutrophilic dermatoses and inflammatory bowel diseases.

    Science.gov (United States)

    Marzano, A V; Menicanti, C; Crosti, C; Trevisan, V

    2013-04-01

    Pyoderma gangrenosum (PG) and Sweet's Syndrome (SS) are inflammatory skin diseases caused by the accumulation of neutrophils in the skin and, rarely, in internal organs, which led to coining the term of neutrophilic dermatoses (ND) to define these conditions. Recently, ND have been included among the autoinflammatory diseases, which are forms due to mutations of genes regulating the innate immune responses. Both PG and SS are frequently associated with inflammatory bowel diseases (IBD), a group of chronic intestinal disorders which comprises ulcerative colitis and Crohn's disease and whose pathogenesis involves both the innate and adaptive immunity in genetically prone individuals. Patients with IBD develop PG in 1-3% of cases, while SS is rarer. PG presents with deep erythematous-to-violaceous painful ulcers with undermined borders, but bullous, pustular, and vegetative variants can also occur. SS, also known as acute febrile neutrophilic dermatosis, is characterized by the abrupt onset of fever, peripheral neutrophilia, tender erythematous skin lesions and a diffuse neutrophilic dermal infiltrate. In this review that will be focused on PG and SS, we will describe also the aseptic abscesses syndrome, a new entity within the spectrum of ND which frequently occurs in association with IBD and is characterized by deep abscesses mainly involving the spleen and skin and by polymorphic cutaneous manifestations including PG- and SS-like lesions.

  4. Ranitidine improves postoperative monocyte and neutrophil function

    DEFF Research Database (Denmark)

    Nielsen, Hans Jørgen; Nielsen, H; Jensen, S;

    1994-01-01

    BACKGROUND: The histamine H2-receptor antagonist ranitidine hydrochloride has been shown to improve trauma-, blood transfusion-, and sepsis-induced immunosuppression. OBJECTIVE: To evaluate the effect of ranitidine on postoperative impairment in monocyte and neutrophil function. METHODS: Twenty...... difference (P detected. There were no infectious complications in ranitidine-treated patients. CONCLUSION: These results support previous studies...

  5. Modulation of neutrophil apoptosis by antimicrobial peptides.

    Science.gov (United States)

    Nagaoka, Isao; Suzuki, Kaori; Niyonsaba, François; Tamura, Hiroshi; Hirata, Michimasa

    2012-01-01

    Peptide antibiotics possess the potent antimicrobial activities against invading microorganisms and contribute to the innate host defense. Human antimicrobial peptides, α-defensins (human neutrophil peptides, HNPs), human β-defensins (hBDs), and cathelicidin (LL-37) not only exhibit potent bactericidal activities against Gram-negative and Gram-positive bacteria, but also function as immunomodulatory molecules by inducing cytokine and chemokine production, and inflammatory and immune cell activation. Neutrophil is a critical effector cell in host defense against microbial infection, and its lifespan is regulated by various pathogen- and host-derived substances. Here, we provided the evidence that HNP-1, hBD-3, and LL-37 cannot only destroy bacteria but also potently modulate (suppress) neutrophil apoptosis, accompanied with the phosphorylation of ERK-1/-2, the downregulation of tBid (an proapoptotic protein) and upregulation of Bcl-xL (an antiapoptotic protein), and the inhibition of mitochondrial membrane potential change and caspase 3 activity, possibly via the actions on the distinct receptors, the P2Y6 nucleotide receptor, the chemokine receptor CCR6, and the low-affinity formyl-peptide receptor FPRL1/the nucleotide receptor P2X7, respectively. Suppression of neutrophil apoptosis results in the prolongation of their lifespan and may be advantageous for the host defense against bacterial invasion.

  6. On the mechanism of oscillations in neutrophils

    DEFF Research Database (Denmark)

    Brasen, Jens Christian; Barington, Torben; Olsen, Lars Folke

    2010-01-01

    We have investigated the regulation of the oscillatory generation of H(2)O(2) and oscillations in shape and size in neutrophils in suspension. The oscillations are independent of cell density and hence do not represent a collective phenomena. Furthermore, the oscillations are independent of the e...

  7. Live Brugia malayi microfilariae inhibit transendothelial migration of neutrophils and monocytes.

    Directory of Open Access Journals (Sweden)

    Jan-Hendrik Schroeder

    Full Text Available Lymphatic filariasis is a major tropical disease caused by the parasite Brugia malayi. Microfilariae (Mf circulate in the peripheral blood for 2-3 hours in synchronisation with maximal feeding of the mosquito vector. When absent from the peripheral blood, Mf sequester in the capillaries of the lungs. Mf are therefore in close contact with vascular endothelial cells (EC and may induce EC immune function and/or wound repair mechanisms such as angiogenesis. In this study, Mf were co-cultured with human umbilical vein EC (HUVEC or human lung microvascular EC (HLMVEC and the transendothelial migration of leukocyte subsets was analysed. In addition, the protein and/or mRNA expression of chemokine, cytokine and angiogenic mediators in endothelial cells in the presence of live microfilariae were measured by a combination of cDNA arrays, protein arrays, ELISA and fluorescence antibody tests.Surprisingly, our findings indicate that Mf presence partially blocked transendothelial migration of monocytes and neutrophils, but not lymphocytes. However, Mf exposure did not result in altered vascular EC expression of key mediators of the tethering stage of extravasation, such as ICAM-1, VCAM-1 and various chemokines. To further analyse the immunological function of vascular EC in the presence of Mf, we measured the mRNA and/or protein expression of a number of pro-inflammatory mediators. We found that expression levels of the mediators tested were predominantly unaltered upon B. malayi Mf exposure. In addition, a comparison of angiogenic mediators induced by intact Mf and Wolbachia-depleted Mf revealed that even intact Mf induce the expression of remarkably few angiogenic mediators in vascular EC. Our study suggests that live microfilariae are remarkably inert in their induction and/or activation of vascular cells in their immediate local environment. Overall, this work presents important insights into the immunological function of the vascular endothelium during

  8. Periodontal Ligament Stem Cells Regulate Apoptosis of Neutrophils

    Science.gov (United States)

    Wang, Qing; Ding, Gang; Xu, Xin

    2017-01-01

    Abstract Periodontal ligament stem cells (PDLSCs) are promising cell resource for the cell-based therapy for periodontitis and regeneration of bio-root. In this study, we investigated the effect of PDLSCs on neutrophil, a critical constituent of innate immunity, and the underlying mechanisms. The effect of PDLSCs on the proliferation and apoptosis of resting neutrophils and IL-8 activated neutrophils was tested under cell-cell contact culture and Transwell culture, with or without anti-IL-6 neutralizing antibody. We found that PDLSCs could promote the proliferation and reduce the apoptosis of neutrophils whether under cell-cell contact or Transwell culture. Anti-IL-6 antibody reduced PDLSCs-mediated inhibition of neutrophil apoptosis. IL-6 at the concentration of 10ng/ml and 20ng/ml could inhibit neutrophil apoptosis statistically. Collectively, PDLSCs could reduce the apoptosis of neutrophils via IL-6.

  9. Escape of Mycobacterium tuberculosis from oxidative killing by neutrophils.

    Science.gov (United States)

    Corleis, Björn; Korbel, Daniel; Wilson, Robert; Bylund, Johan; Chee, Ronnie; Schaible, Ulrich E

    2012-07-01

    Neutrophils enter sites of infection, where they can eliminate pathogenic bacteria in an oxidative manner. Despite their predominance in active tuberculosis lesions, the function of neutrophils in this important human infection is still highly controversial. We observed that virulent Mycobacterium tuberculosis survived inside human neutrophils despite prompt activation of these defence cells' microbicidal effectors. Survival of M. tuberculosis was accompanied by necrotic cell death of infected neutrophils. Necrotic cell death entirely depended on radical oxygen species production since chronic granulomatous disease neutrophils were protected from M. tuberculosis-triggered necrosis. More, importantly, the M. tuberculosis ΔRD1 mutant failed to induce neutrophil necrosis rendering this strain susceptible to radical oxygen species-mediated killing. We conclude that this virulence function is instrumental for M. tuberculosis to escape killing by neutrophils and contributes to pathogenesis in tuberculosis.

  10. Phagocytosis and killing of Streptococcus suis by porcine neutrophils.

    Science.gov (United States)

    Chabot-Roy, Geneviève; Willson, Philip; Segura, Mariela; Lacouture, Sonia; Gottschalk, Marcelo

    2006-07-01

    Streptococcus suis serotype 2 is an important swine pathogen responsible for diverse infections, mainly meningitis. Virulence factors and the pathogenesis of infection are not well understood. Neutrophils may play an important role in the pathogenesis of infection given that infiltration by neutrophils and mononuclear cells are frequently observed in lesions caused by S. suis. The objective of this work was to study the interactions between S. suis serotype 2 and porcine neutrophils. Results showed that suilysin is toxic to neutrophils and this could help S. suis evade innate immunity. Moreover, suilysin appears to affect complement-dependent killing by decreasing the opsonization of S. suis and the bactericidal capacity of neutrophils. Our results confirm that capsule polysaccharide protects S. suis against killing and phagocytosis by neutrophils. We also showed that the presence of specific IgG against S. suis serotype 2 promoted killing by neutrophils, indicating that the induction of a strong humoral response is beneficial for clearance of this pathogen.

  11. The cystic fibrosis neutrophil: a specialized yet potentially defective cell.

    LENUS (Irish Health Repository)

    Hayes, Elaine

    2012-02-01

    Cystic fibrosis (CF) is one of the commonest genetically inherited diseases in the world. It is characterized by recurrent respiratory tract infections eventually leading to respiratory failure. One of the hallmarks of this disease is a persistent and predominantly neutrophil driven inflammation. Neutrophils provide the first line of defence by killing and digesting phagocytosed bacteria and fungi, yet despite advances in our understanding of the molecular and cellular basis of CF, there remains a paradox of why recruited CF neutrophils fail to eradicate bacterial infections in the lung. This review describes mechanisms involved in neutrophil migration, microbial killing and apoptosis leading to inflammatory resolution. We discuss dysregulated neutrophil activity and consider genetic versus inflammatory neutrophil reprogramming in CF and ultimately pharmacological modulation of the CF neutrophil for therapeutic intervention.

  12. The cystic fibrosis neutrophil: a specialized yet potentially defective cell.

    LENUS (Irish Health Repository)

    Hayes, Elaine

    2011-04-01

    Cystic fibrosis (CF) is one of the commonest genetically inherited diseases in the world. It is characterized by recurrent respiratory tract infections eventually leading to respiratory failure. One of the hallmarks of this disease is a persistent and predominantly neutrophil driven inflammation. Neutrophils provide the first line of defence by killing and digesting phagocytosed bacteria and fungi, yet despite advances in our understanding of the molecular and cellular basis of CF, there remains a paradox of why recruited CF neutrophils fail to eradicate bacterial infections in the lung. This review describes mechanisms involved in neutrophil migration, microbial killing and apoptosis leading to inflammatory resolution. We discuss dysregulated neutrophil activity and consider genetic versus inflammatory neutrophil reprogramming in CF and ultimately pharmacological modulation of the CF neutrophil for therapeutic intervention.

  13. Regulators and Effectors of Arf GTPases in Neutrophils.

    Science.gov (United States)

    Gamara, Jouda; Chouinard, François; Davis, Lynn; Aoudjit, Fawzi; Bourgoin, Sylvain G

    2015-01-01

    Polymorphonuclear neutrophils (PMNs) are key innate immune cells that represent the first line of defence against infection. They are the first leukocytes to migrate from the blood to injured or infected sites. This process involves molecular mechanisms that coordinate cell polarization, delivery of receptors, and activation of integrins at the leading edge of migrating PMNs. These phagocytes actively engulf microorganisms or form neutrophil extracellular traps (NETs) to trap and kill pathogens with bactericidal compounds. Association of the NADPH oxidase complex at the phagosomal membrane for production of reactive oxygen species (ROS) and delivery of proteolytic enzymes into the phagosome initiate pathogen killing and removal. G protein-dependent signalling pathways tightly control PMN functions. In this review, we will focus on the small monomeric GTPases of the Arf family and their guanine exchange factors (GEFs) and GTPase activating proteins (GAPs) as components of signalling cascades regulating PMN responses. GEFs and GAPs are multidomain proteins that control cellular events in time and space through interaction with other proteins and lipids inside the cells. The number of Arf GAPs identified in PMNs is expanding, and dissecting their functions will provide important insights into the role of these proteins in PMN physiology.

  14. SEXUAL DIMORPHISM IN MORPHOLOGY AND MORPHOMETRY OF NEUTROPHIL DRUMSTICKS

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    Sharmila Tupakula

    2014-12-01

    Full Text Available Introduction: Sex chromatin is a chromatin mass of 1 micron size usually seen at the periphery of nucleus in females. In the literature majority reported its absence in males while few reported its low incidence in males. The term ‘sex chromatin’ comprises two superficially dissimilar structures the “Barr body” present in epithelial and other tissue cells and the “Drumstick” of the polymorphonuclear leucocytes. Materials and methods: The present study was conducted to observe the morphology, morphometry and percentage incidence of Drumsticks in the blood neutrophils of 110 individuals ranging from 17-30 age group and both sexes using a calibrated ocular/eye piece micrometer. Results: The percentage incidence of drumsticks including non-specific appendages as well as the total number of true drumsticks in females exceeds that in males. Four different types of nonspecific appendages-sessile nodules, racket structures, minor lobes and small clubs were found in the blood neutrophils along with the drumsticks. A higher percentage of non-specific appendages i.e. minor lobes (46.2%, racket structures (42.3%, and small clubs (11.5% were observed in males and sessile nodules were found only in females. Conclusion: Observations on morphology, morphometry and percentage incidence of polymorphonuclear drumsticks presented a valuable data on sex differences.

  15. Regulators and Effectors of Arf GTPases in Neutrophils

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    Jouda Gamara

    2015-01-01

    Full Text Available Polymorphonuclear neutrophils (PMNs are key innate immune cells that represent the first line of defence against infection. They are the first leukocytes to migrate from the blood to injured or infected sites. This process involves molecular mechanisms that coordinate cell polarization, delivery of receptors, and activation of integrins at the leading edge of migrating PMNs. These phagocytes actively engulf microorganisms or form neutrophil extracellular traps (NETs to trap and kill pathogens with bactericidal compounds. Association of the NADPH oxidase complex at the phagosomal membrane for production of reactive oxygen species (ROS and delivery of proteolytic enzymes into the phagosome initiate pathogen killing and removal. G protein-dependent signalling pathways tightly control PMN functions. In this review, we will focus on the small monomeric GTPases of the Arf family and their guanine exchange factors (GEFs and GTPase activating proteins (GAPs as components of signalling cascades regulating PMN responses. GEFs and GAPs are multidomain proteins that control cellular events in time and space through interaction with other proteins and lipids inside the cells. The number of Arf GAPs identified in PMNs is expanding, and dissecting their functions will provide important insights into the role of these proteins in PMN physiology.

  16. Neutrophil extracellular traps involvement in corneal fungal infection

    Science.gov (United States)

    Zhao, Yingying; Zhang, Fan; Wan, Ting; Fan, Fangli; Xie, Xin; Lin, Zhenyun

    2016-01-01

    Purpose Neutrophils release neutrophil extracellular traps (NETs) when defending against invading microorganisms. We investigated the existence of NETs in fungal keratitis. Methods Fourteen patients with unilateral fungal keratitis were included. Detailed information about each patient was recorded, including (1) patient history (onset of symptoms and previous therapy), (2) ocular examination findings by slit-lamp biomicroscopy, (3) laboratory findings from direct smear examination and culture of corneal scrapings, (4) NET formation, and (5) treatment strategy and prognosis. Immunofluorescence staining was used to evaluate the existence of NETs on corneal scrapings. The relationship between the quantification of NETs and the clinical character of the fungal keratitis was identified. Results NETs were identified in all 14 patients. Patients with a higher grade of NET formation and fewer fungal hyphae always showed a good treatment response and a short course of infection. NETs were consistently found mixed with fungal hyphae in the corneal scrapings from infected patients. No statistical significance was found between the grade of NETs formed and the course of infection before presentation, and no relationship between the quantification of NETs and the size of the ulcer was found. Conclusions The results suggest that NETs are involved in fungal keratitis. The number of NETs in infected corneas may provide a tool for evaluating the prognosis for fungal keratitis. PMID:27559290

  17. A brief etymology of the collateral circulation.

    Science.gov (United States)

    Faber, James E; Chilian, William M; Deindl, Elisabeth; van Royen, Niels; Simons, Michael

    2014-09-01

    It is well known that the protective capacity of the collateral circulation falls short in many individuals with ischemic disease of the heart, brain, and lower extremities. In the past 15 years, opportunities created by molecular and genetic tools, together with disappointing outcomes in many angiogenic trials, have led to a significant increase in the number of studies that focus on: understanding the basic biology of the collateral circulation; identifying the mechanisms that limit the collateral circulation's capacity in many individuals; devising methods to measure collateral extent, which has been found to vary widely among individuals; and developing treatments to increase collateral blood flow in obstructive disease. Unfortunately, accompanying this increase in reports has been a proliferation of vague terms used to describe the disposition and behavior of this unique circulation, as well as the increasing misuse of well-ensconced ones by new (and old) students of collateral circulation. With this in mind, we provide a brief glossary of readily understandable terms to denote the formation, adaptive growth, and maladaptive rarefaction of collateral circulation. We also propose terminology for several newly discovered processes that occur in the collateral circulation. Finally, we include terms used to describe vessels that are sometimes confused with collaterals, as well as terms describing processes active in the general arterial-venous circulation when ischemic conditions engage the collateral circulation. We hope this brief review will help unify the terminology used in collateral research.

  18. Taurine modulates neutrophil function but potentiates uropathogenic E. coli infection in the murine bladder.

    LENUS (Irish Health Repository)

    Condron, Claire

    2010-08-01

    Eradication of a urinary tract infection (UTI) appears to be related to a number of innate host defence mechanisms and their interactions with invading bacteria. Recurrent UTIs (rUTIs) pose a difficult problem in that these bacteria use both host and bacterial factors to evade elimination. Neutrophil bactericidal function is depressed, both systemically and in urine, in patients with a history of recurrent UTI. Taurine is a semi-essential amino acid and is successful in preserving neutrophil bactericidal function in urine. Taurine may preserve neutrophil function at the urothelium and thus aid UTI resolution. Adult female (6 weeks old) C57Bl\\/6 mice were randomised into three groups: a saline gavage only control group, a saline gavage + E. coli group, and a taurine gavage + E. coli group [21 g\\/70 kg taurine in 0.9% normal saline (N\\/S) for 5 days]. Whilst taurine gavage pre-treatment resulted in increased serum neutrophils respiratory burst activity, at the urothelial-endothelial interface it caused higher colony forming units in the urine and a higher incidence of E. coli invasion in the bladder wall with no evidence of increased bladder wall neutrophils infiltration on MPO assay of histological assessment. Histologically there was also evidence of reduced bladder inflammation and urothelial cell apoptosis. In conclusion, taurine effectively increases neutrophils activity but given its anti-inflammatory properties, at the expense of decreased urothelial-endothelial activation thus preventing clearance of active E. coli infection in the bladder. Despite the negative results, this study demonstrates the importance of modulating interactions at the urothelial interface.

  19. β2 integrin mediates hantavirus-induced release of neutrophil extracellular traps.

    Science.gov (United States)

    Raftery, Martin J; Lalwani, Pritesh; Krautkrӓmer, Ellen; Peters, Thorsten; Scharffetter-Kochanek, Karin; Krüger, Renate; Hofmann, Jörg; Seeger, Karl; Krüger, Detlev H; Schönrich, Günther

    2014-06-30

    Rodent-borne hantaviruses are emerging human pathogens that cause severe human disease. The underlying mechanisms are not well understood, as hantaviruses replicate in endothelial and epithelial cells without causing any cytopathic effect. We demonstrate that hantaviruses strongly stimulated neutrophils to release neutrophil extracellular traps (NETs). Hantavirus infection induced high systemic levels of circulating NETs in patients and this systemic NET overflow was accompanied by production of autoantibodies to nuclear antigens. Analysis of the responsible mechanism using neutrophils from β2 null mice identified β2 integrin receptors as a master switch for NET induction. Further experiments suggested that β2 integrin receptors such as complement receptor 3 (CR3) and 4 (CR4) may act as novel hantavirus entry receptors. Using adenoviruses, we confirmed that viral interaction with β2 integrin induced strong NET formation. Collectively, β2 integrin-mediated systemic NET overflow is a novel viral mechanism of immunopathology that may be responsible for characteristic aspects of hantavirus-associated disease such as kidney and lung damage.

  20. In vivo characterization of neutrophil extracellular traps in various organs of a murine sepsis model.

    Directory of Open Access Journals (Sweden)

    Koji Tanaka

    Full Text Available Neutrophil extracellular traps (NETs represent extracellular microbial trapping and killing. Recently, it has been implicated in thrombogenesis, autoimmune disease, and cancer progression. The aim of this study was to characterize NETs in various organs of a murine sepsis model in vivo and to investigate their associations with platelets, leukocytes, or vascular endothelium. NETs were classified as two distinct forms; cell-free NETs that were released away from neutrophils and anchored NETs that were anchored to neutrophils. Circulating cell-free NETs were characterized as fragmented or cotton-like structures, while anchored NETs were characterized as linear, reticular, membranous, or spot-like structures. In septic mice, both anchored and cell-free NETs were significantly increased in postcapillary venules of the cecum and hepatic sinusoids with increased leukocyte-endothelial interactions. NETs were also observed in both alveolar space and pulmonary capillaries of the lung. The interactions of NETs with platelet aggregates, leukocyte-platelet aggregates or vascular endothelium of arterioles and venules were observed in the microcirculation of septic mice. Microvessel occlusions which may be caused by platelet aggregates or leukocyte-platelet aggregates and heterogeneously decreased blood flow were also observed in septic mice. NETs appeared to be associated with the formation of platelet aggregates or leukocyte-platelet aggregates. These observational findings may suggest the adverse effect of intravascular NETs on the host during a sepsis.

  1. Induction of Neutrophil Extracellular Traps in Shiga Toxin-Associated Hemolytic Uremic Syndrome.

    Science.gov (United States)

    Ramos, Maria Victoria; Mejias, Maria Pilar; Sabbione, Florencia; Fernandez-Brando, Romina Jimena; Santiago, Adriana Patricia; Amaral, Maria Marta; Exeni, Ramon; Trevani, Analia Silvina; Palermo, Marina Sandra

    2016-01-01

    Hemolytic uremic syndrome (HUS), a vascular disease characterized by hemolytic anemia, thrombocytopenia, and acute renal failure, is caused by enterohemorrhagic Shiga toxin (Stx)-producing bacteria, which mainly affect children. Besides Stx, the inflammatory response mediated by neutrophils (PMN) is essential to HUS evolution. PMN can release neutrophil extracellular traps (NET) composed of DNA, histones, and other proteins. Since NET are involved in infectious and inflammatory diseases, the aim of this work was to investigate the contribution of NET to HUS. Plasma from HUS patients contained increased levels of circulating free-DNA and nucleosomes in comparison to plasma from healthy children. Neutrophils from HUS patients exhibited a greater capacity to undergo spontaneous NETosis. NET activated human glomerular endothelial cells, stimulating secretion of the proinflammatory cytokines IL-6 and IL-8. Stx induced PMN activation as judged by its ability to trigger reactive oxygen species production, increase CD11b and CD66b expression, and induce NETosis in PMN from healthy donors. During HUS, NET can contribute to the inflammatory response and thrombosis in the microvasculature and thus to renal failure. Intervention strategies to inhibit inflammatory mechanisms mediated by PMN, such as NETosis, could have a potential therapeutic impact towards amelioration of the severity of HUS.

  2. NOD2 dependent neutrophil recruitment is required for early protective immune responses against infectious Litomosoides sigmodontis L3 larvae

    Science.gov (United States)

    Ajendra, Jesuthas; Specht, Sabine; Ziewer, Sebastian; Schiefer, Andrea; Pfarr, Kenneth; Parčina, Marijo; Kufer, Thomas A.; Hoerauf, Achim; Hübner, Marc P.

    2016-01-01

    Nucleotide-binding oligomerization domain-containing protein 2 (NOD2) recognizes muramyl dipeptide (MDP) of bacterial cell walls, triggering NFκB-induced pro-inflammation. As most human pathogenic filariae contain Wolbachia endobacteria that synthesize the MDP-containing cell wall precursor lipid II, NOD2’s role during infection with the rodent filaria Litomosoides sigmodontis was investigated. In NFκB reporter-cells, worm-extract containing Wolbachia induced NOD2 and NOD1. NOD2-deficient mice infected with L. sigmodontis had significantly more worms than wildtype controls early in infection. Increased worm burden was not observed after subcutaneous infection, suggesting that protective NOD2-dependent immune responses occur within the skin. Flow cytometry demonstrated that neutrophil recruitment to the skin was impaired in NOD2−/− mice after intradermal injection of third stage larvae (L3), and blood neutrophil numbers were reduced after L. sigmodontis infection. PCR array supported the requirement of NOD2 for recruitment of neutrophils to the skin, as genes associated with neutrophil recruitment and activation were downregulated in NOD2−/− mice after intradermal L3 injection. Neutrophil depletion before L. sigmodontis infection increased worm recovery in wildtype mice, confirming that neutrophils are essential against invading L3 larvae. This study indicates that NOD-like receptors are implemented in first-line protective immune responses against filarial nematodes. PMID:28004792

  3. Depletion of Neutrophils Exacerbates the Early Inflammatory Immune Response in Lungs of Mice Infected with Paracoccidioides brasiliensis

    Science.gov (United States)

    Lopera, Damaris; Urán-Jiménez, Martha Eugenia

    2016-01-01

    Neutrophils predominate during the acute phase of the Paracoccidioides brasiliensis infection. Herein, we determined the role of the neutrophil during the early stages of experimental pulmonary paracoccidioidomycosis using a monoclonal antibody (mAb) specific for neutrophils. Male BALB/c mice were inoculated intranasally with 1.5 × 106 or 2 × 106 P. brasiliensis yeast cells. The mAb was administered 24 h before infection, followed by doses every 48 h until mice were sacrificed. Survival time was evaluated and mice were sacrificed at 48 h and 96 h after inoculation to assess cellularity, fungal load, cytokine/chemokine levels, and histopathological analysis. Neutrophils from mAb-treated mice were efficiently depleted (99.04%). Eighty percent of the mice treated with the mAb and infected with 1.5 × 106 yeast cells died during the first two weeks after infection. When mice were treated and infected with 2 × 106 yeast cells, 100% of them succumbed by the first week after infection. During the acute inflammatory response significant increases in numbers of eosinophils, fungal load and levels of proinflammatory cytokines/chemokines were observed in the mAb-treated mice. We also confirmed that neutrophils are an important source of IFN-γ and IL-17. These results indicate that neutrophils are essential for protection as well as being important for regulating the early inflammatory immune response in experimental pulmonary paracoccidioidomycosis. PMID:27642235

  4. Blood neutrophil bactericidal activity against methicillin-resistant and methicillin-sensitive Staphylococcus aureus during cardiac surgery.

    Science.gov (United States)

    Mekontso-Dessap, Armand; Honoré, Stéphanie; Kirsch, Matthias; Plonquet, Anne; Fernandez, Eric; Touqui, Lhousseine; Farcet, Jean-Pierre; Soussy, Claude-James; Loisance, Daniel; Delclaux, Christophe

    2005-08-01

    Whether methicillin-resistant Staphylococcus aureus (MRSA) constitutes per se an independent risk factor for morbidity and mortality after surgery as compared with methicillin-sensitive Staphylococcus aureus (MSSA) remains a subject of debate. The aim of this study was to assess whether innate defenses against MRSA and MSSA strains are similarly impaired after cardiac surgery. Both intracellular (isolated neutrophil functions) and extracellular (plasma) defenses of 12 patients undergoing scheduled cardiac surgery were evaluated preoperatively (day 0) and postoperatively (day 3) against two MSSA strains with a low level of catalase secretion and two MRSA strains with a high level of catalase secretion, inasmuch as SA killing by neutrophils relies on oxygen-dependent mechanisms. After surgery, an increase in plasma concentration of IL-10, an anti-inflammatory cytokine able to inhibit reactive oxygen species secretion and bactericidal activity of neutrophils, was evidenced. Despite the fact that univariate analysis suggested a specific impairment of neutrophil functions against MRSA strains, two-way repeated-measures ANOVA failed to demonstrate that the effect of S. aureus phenotype was significant. On the other hand, an increase in type-II secretory phospholipase A2 activity, a circulating enzyme involved in SA lysis, was evidenced and was associated with an enhancement of extracellular defenses (bactericidal activity of plasma) against MRSA. Overall, cardiac surgery and S. aureus phenotype had a significant effect on plasma bactericidal activity. Cardiac surgery was characterized by enhanced antibacterial defenses of plasma, whereas neutrophil killing properties were reduced. The overall effect of S. aureus phenotype on neutrophil functions did not seem significant.

  5. Peripheral and intrauterine neutrophil function in the cow: the influence of endogenous and exogenous sex steroid hormones.

    Science.gov (United States)

    Subandrio, A L; Sheldon, I M; Noakes, D E

    2000-05-01

    It has been accepted for many years that the susceptibility of the genital tract to infection is reduced during the follicular phase compared with the luteal phase of the estrous cycle. Since the role of intrauterine neutrophils is paramount in the elimination of bacteria, it can be hypothesized that these differences in resistance to infection could be mediated by differences in uterine-derived neutrophil function. In order to test this hypothesis two groups of cows were used in this study. Group 1 cows (n=5) were studied at estrus, diestrus, after ovariectomy, after exogenous estradiol and after progesterone treatment, at which time they underwent intrauterine infusion with 1% oyster glycogen (OG) and a bacterial-free filtrate (BFF) of Actinomyces genes (BFF), the latter having been recovered from a clinical case of endometritis; neutrophils were harvested by flushing from the lumen 15 to 18 h later. A peripheral blood sample was collected at the time of flushing for the assay of estradiol and progesterone for a WBC and differential count and for the harvesting of neutrophils using a Percoll single-stage discontinuous gradient. After the recovery of the cells they were re-suspended in HBSS. Group 2 (n=4) were infused with BFF during during all reproductive states as Group 1, but with OG only after ovariectomy and after treatment with progesterone and estradiol. Neutrophil chemotaxis was assessed by measuring their migration using a modified Boyden chamber and Zymogen-activated serum as a chemoattractant. Phagocytic activity was measured by determining the number of Candida albicans ingested by each neutrophil after incubation. The percentage of kill was determined using a radiometric assay in which C. albicans was labeled with L-(5-3H) Proline. Peripheral WBC concentration was not influenced by the reproductive state of the cow; however, the mean neutrophil concentration was significantly different between the reproductive states (P<0.001) and between individual

  6. Neutrophil extracellular traps in tissue pathology.

    Science.gov (United States)

    Nakazawa, Daigo; Kumar, Santosh; Desai, Jyaysi; Anders, Hans-Joachim

    2017-03-01

    Neutrophil extracellular traps (NETs) are innate immune systems against invading pathogens. NETs are characterized as released DNA mixed with cytoplasmic antimicrobial proteins such as myeloperoxidase, proteinase3 and neutrophil elastase. While NETs are thought to have an important role in host defense, recent work has suggested that NETs contribute to tissue injury in non-infectious disease states. Uncontrolled NET formation in autoimmune diseases, metabolic disorders, cancers and thrombotic diseases can exacerbate a disease or even be a major initiator of tissue injury. But spotting NETs in tissues is not easy. Here we review the available histopathological evidence on the presence of NETs in a variety of diseases. We discuss technical difficulties and potential sources of misinterpretation while trying to detect NETs in tissue samples.

  7. Neutrophil myeloperoxidase destruction by ultraviolet irradiation

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    Hanker, J.; Giammara, B.; Strauss, G.

    1988-01-01

    The peroxidase activity of enriched leukocyte preparations on coverslips was determined cytochemically with a newly developed method. The techniques utilizes diaminobenzidine medium and cupric nitrate intensification and is suitable for analysis with light microscopy, SEM, and TEM. Blood specimens from control individuals were studied with and without in vitro UV irradiation and compared with those from psoriasis patients exposed therapeutically to various types of UV in phototherapy. All UV irradiated samples showed diminished neutrophil myeloperoxidase (MP) activity although that of the principal eosinophil peroxidase was unaffected. The SEMs supported the contention that decreased neutrophil MP activity might be related to UV induced degranulation. It is believed to be possible, eventually, to equate the observed MP degranulation effect after UV irradiation with diminished ability to fight bacterial infections.

  8. Leukotriene B4-Neutrophil Elastase Axis Drives Neutrophil Reverse Transendothelial Cell Migration In Vivo.

    Science.gov (United States)

    Colom, Bartomeu; Bodkin, Jennifer V; Beyrau, Martina; Woodfin, Abigail; Ody, Christiane; Rourke, Claire; Chavakis, Triantafyllos; Brohi, Karim; Imhof, Beat A; Nourshargh, Sussan

    2015-06-16

    Breaching endothelial cells (ECs) is a decisive step in the migration of leukocytes from the vascular lumen to the extravascular tissue, but fundamental aspects of this response remain largely unknown. We have previously shown that neutrophils can exhibit abluminal-to-luminal migration through EC junctions within mouse cremasteric venules and that this response is elicited following reduced expression and/or functionality of the EC junctional adhesion molecule-C (JAM-C). Here we demonstrate that the lipid chemoattractant leukotriene B4 (LTB4) was efficacious at causing loss of venular JAM-C and promoting neutrophil reverse transendothelial cell migration (rTEM) in vivo. Local proteolytic cleavage of EC JAM-C by neutrophil elastase (NE) drove this cascade of events as supported by presentation of NE to JAM-C via the neutrophil adhesion molecule Mac-1. The results identify local LTB4-NE axis as a promoter of neutrophil rTEM and provide evidence that this pathway can propagate a local sterile inflammatory response to become systemic.

  9. Leukotriene B4-Neutrophil Elastase Axis Drives Neutrophil Reverse Transendothelial Cell Migration In Vivo

    Science.gov (United States)

    Colom, Bartomeu; Bodkin, Jennifer V.; Beyrau, Martina; Woodfin, Abigail; Ody, Christiane; Rourke, Claire; Chavakis, Triantafyllos; Brohi, Karim; Imhof, Beat A.; Nourshargh, Sussan

    2015-01-01

    Summary Breaching endothelial cells (ECs) is a decisive step in the migration of leukocytes from the vascular lumen to the extravascular tissue, but fundamental aspects of this response remain largely unknown. We have previously shown that neutrophils can exhibit abluminal-to-luminal migration through EC junctions within mouse cremasteric venules and that this response is elicited following reduced expression and/or functionality of the EC junctional adhesion molecule-C (JAM-C). Here we demonstrate that the lipid chemoattractant leukotriene B4 (LTB4) was efficacious at causing loss of venular JAM-C and promoting neutrophil reverse transendothelial cell migration (rTEM) in vivo. Local proteolytic cleavage of EC JAM-C by neutrophil elastase (NE) drove this cascade of events as supported by presentation of NE to JAM-C via the neutrophil adhesion molecule Mac-1. The results identify local LTB4-NE axis as a promoter of neutrophil rTEM and provide evidence that this pathway can propagate a local sterile inflammatory response to become systemic. PMID:26047922

  10. Autophagy is induced by anti-neutrophil cytoplasmic Abs and promotes neutrophil extracellular traps formation.

    Science.gov (United States)

    Sha, Li-Li; Wang, Huan; Wang, Chen; Peng, Hong-Ying; Chen, Min; Zhao, Ming-Hui

    2016-11-01

    Dysregulated neutrophil extracellular traps (NETs) formation contributes to the pathogenesis of anti-neutrophil cytoplasmic Ab (ANCA)-associated vasculitis (AAV). Increasing evidence indicates that autophagy is involved in the process of NETs formation. In this study, we aimed to investigate whether ANCA could induce autophagy in the process of NETs formation. Autophagy was detected using live cell imaging, microtubule-associated protein light chain 3B (LC3B) accumulation and Western blotting. The results showed that autophagy vacuolization was detected in neutrophils treated with ANCA-positive IgG by live cell imaging. This effect was enhanced by rapamycin, the autophagy inducer, and weakened by 3-methyladenine (3-MA), the autophagy inhibitor. In line with these results, the autophagy marker, LC3B, showed a punctate distribution pattern in the neutrophils stimulated with ANCA-positive IgG. In the presence of rapamycin, LC3B accumulation was further increased; however, this effect was attenuated by 3-MA. Moreover, incubated with ANCA-positive IgG, the NETosis rate significantly increased compared with the unstimulated group. And, the rate significantly increased or decreased in the neutrophils pretreated with rapamycin or 3-MA, respectively, as compared with the cells incubated with ANCA-positive IgG. Overall, this study demonstrates that autophagy is induced by ANCA and promotes ANCA-induced NETs formation.

  11. Treadmill exercise induces neutrophil recruitment into muscle tissue in a reactive oxygen species-dependent manner. An intravital microscopy study.

    Directory of Open Access Journals (Sweden)

    Albená Nunes-Silva

    Full Text Available Intense exercise is a physiological stress capable of inducing the interaction of neutrophils with muscle endothelial cells and their transmigration into tissue. Mechanisms driving this physiological inflammatory response are not known. Here, we investigate whether production of reactive oxygen species is relevant for neutrophil interaction with endothelial cells and recruitment into the quadriceps muscle in mice subjected to the treadmill fatiguing exercise protocol. Mice exercised until fatigue by running for 56.3±6.8 min on an electric treadmill. Skeletal muscle was evaluated by intravital microscopy at different time points after exercise, and then removed to assess local oxidative stress and histopathological analysis. We observed an increase in plasma lactate and creatine kinase (CK concentrations after exercise. The numbers of monocytes, neutrophils, and lymphocytes in blood increased 12 and 24 hours after the exercise. Numbers of rolling and adherent leukocytes increased 3, 6, 12, and 24 hours post-exercise, as assessed by intravital microscopy. Using LysM-eGFP mice and confocal intravital microscopy technology, we show that the number of transmigrating neutrophils increased 12 hours post-exercise. Mutant gp91phox-/- (non-functional NADPH oxidase mice and mice treated with apocynin showed diminished neutrophil recruitment. SOD treatment promoted further adhesion and transmigration of leukocytes 12 hours after the exercise. These findings confirm our hypothesis that treadmill exercise increases the recruitment of leukocytes to the postcapillary venules, and NADPH oxidase-induced ROS plays an important role in this process.

  12. Role of neutrophilic inflammation in ozone-induced epithelial alterations in the nasal airways of rats

    Science.gov (United States)

    Cho, Hye Youn

    Ozone is a principal oxidant air pollutant in photochemical smog. Epithelial cells lining the centriacinar region of lung and the proximal aspects of nasal passage are primary target sites for ozone-induced injury in laboratory animals. Acute exposure of rats to high ambient concentrations of ozone (e.g., 0.5 ppm) results in neutrophilic inflammation, epithelial hyperplasia and mucous cell metaplasia (MCM) in the nasal transitional epithelium (NTE) lining the proximal nasal airways. The principal purpose of the present study was to investigate the role of pre-metaplastic cellular responses, especially neutrophilic inflammation, in the pathogenesis of ozone-induced MCM in rat NTE. For this purpose, three specific hypotheses-based whole-animal inhalation studies were conducted. Male F344/N rats were exposed in whole-body inhalation chambers to 0 (filtered air) or 0.5 ppm ozone for 1-3 days (8 h/day). Histochemical, immunochemical, molecular and morphometric techniques were used to investigate the ozone-induced cellular and molecular events in the NTE. Two in vitro studies were also conducted to examine the effects of ozone-inducible cytokines (i.e., tumor necrosis factor-alpha; TNF- a, and interleukin-6; IL-6) on mucin gene (rMuc-5AC) expression. Ozone induced a rapid increase of rMuc-5AC mRNA in nasal tissues within hours after the start of exposure. It preceded the appearance of MCM, and persisted with MCM. Ozone-induced neutrophilic inflammation accompanied the mucin gene upregulation, but was resolved when MCM first appeared in the NTE. Antibody-mediated depletion of circulating neutrophils attenuated ozone-induced MCM, although it did not affect the ozone-induced epithelial hyperplasia and mucin mRNA upregulation. In another study, it was found that preexisting neutrophilic rhinitis induced by endotoxin augmented the ozone-induced MCM. However, pre-existing rhinitis did not alter the severity of ozone-induced epithelial hyperplasia and mucin gene upregulation

  13. Phagocytosis and killing of Staphylococcus aureus by human neutrophils.

    Science.gov (United States)

    Lu, Thea; Porter, Adeline R; Kennedy, Adam D; Kobayashi, Scott D; DeLeo, Frank R

    2014-01-01

    Neutrophils are essential for host defense against Staphylococcus aureus infections. Although significant progress has been made, our understanding of neutrophil interactions with S. aureus remains incomplete. To provide a more comprehensive view of this process, we investigated phagocytosis and killing of S. aureus by human neutrophils using varied assay conditions in vitro. A greater percentage of bacteria were internalized by adherent neutrophils compared to those in suspension, and, unexpectedly, uptake of S. aureus by adherent neutrophils occurred efficiently in the absence of opsonins. An antibody specific for S. aureus promoted uptake of unopsonized bacteria in suspension, but had little or no capacity to enhance phagocytosis of S. aureus opsonized with normal human serum or by adherent neutrophils. Collectively, these results indicate that assay conditions can have a significant influence on the phagocytosis and killing of S. aureus by neutrophils. More importantly, the results suggest a vaccine approach directed to enhance opsonophagocytosis alone is not sufficient to promote increased killing of S. aureus by human neutrophils. With the emergence and reemergence of antibiotic-resistant microorganisms, establishing parameters that are optimal for studying neutrophil-S. aureus interactions will pave the way towards developing immune-directed strategies for anti-staphylococcal therapies.

  14. The Number of Circulating Fibrocytes of Skeletal Muscle in Rats after Contusion%大鼠骨骼肌挫伤后外周血源性纤维细胞的数量变化

    Institute of Scientific and Technical Information of China (English)

    李力强; 李骄勇; 于天水; 官大威; 范琰琰; 赵锐; 马文翔; 张书韬; 张舒; 任鹏

    2012-01-01

    Objection To investigate the time-dependent appearance of circulating fibrocytes of skeletal muscle in rats after contusion. Methods The model of skeletal muscle wound was established in rat. The circulating fibrocytes in contused skeletal muscle were detected by CD45 and procollagen I double im-munofluorescence staining method. Results In the control group, CD45- and procollagen I -positive cells were not detected in skeletal muscle. A few CD45 cells were observed aged from 6h to 1d after contusion. A few CD45- and procollagen I-positive cells (fibrocytes) initially gathered in injury area 3d after injury. The ratio of positive fibrocytes significantly increased 5 d after injury. The ratio of fibrocytes was highest at 7 d after contusion and then decreased. The volume of fibrocytes showed bigger with injury time increase compared with 3 d group. The expression of procollagen I and CD45 were weakened at 14 d after injury. Conclusion The circulating fibrocytes are detected in contused skeletal muscle in time-dependent pattern. Circulating fibrocytes may be a marker in the wound age determination for contused skeletal muscle.%目的 探讨大鼠骨骼肌挫伤后损伤区外周血来源的纤维细胞数量变化规律.方法 制作大鼠骨骼肌挫伤模型,应用CD45、procollagen Ⅰ双重免疫荧光染色法检测大鼠骨骼肌挫伤后各时间点外周血来源的纤维细胞的变化.结果 对照组大鼠骨骼肌中未见CD45、procollagen Ⅰ阳性的纤维细胞分布;损伤组大鼠骨骼肌挫伤后6h~1d,仅见少数CD45阳性的单个核细胞;伤后3d,开始有少量CD45、procollagen Ⅰ阳性的纤维细胞聚集于损伤区;伤后5d,阳性的纤维细胞数量明显增加;伤后7d达高峰,此后逐渐减少,同时还发现相对于3d组,纤维细胞的体积随着时间延长逐渐变大;伤后14d,纤维细胞胞质中的CD45和procollagen Ⅰ的表达强度都相应减弱.结论 大鼠骨骼肌挫伤后,挫伤区外周血来源的

  15. Neutrophil activator of matrix metalloproteinase-2 (NAM).

    Science.gov (United States)

    Rollo, Ellen E; Hymowitz, Michelle; Schmidt, Cathleen E; Montana, Steve; Foda, Hussein; Zucker, Stanley

    2006-01-01

    We have isolated a novel soluble factor(s), neutrophil activator of matrix metalloproteinases (NAM), secreted by unstimulated normal human peripheral blood neutrophils that causes the activation of cell secreted promatrix metalloproteinase-2 (proMMP-2). Partially purified preparations of NAM have been isolated from the conditioned media of neutrophils employing gelatin-Sepharose chromatography and differential membrane filter centrifugation. NAM activity, as assessed by exposing primary human umbilical vein endothelial cells (HUVEC) or HT1080 cells to NAM followed by gelatin zymography, was seen within one hour. Tissue inhibitor of metalloproteinase-2 (TIMP-2) and hydroxamic acid derived inhibitors of MMPs (CT1746 and BB94) abrogated the activation of proMMP-2 by NAM, while inhibitors of serine and cysteine proteases showed no effect. NAM also produced an increase in TIMP-2 binding to HUVEC and HT1080 cell surfaces that was inhibited by TIMP-2, CT1746, and BB94. Time-dependent increases in MT1-MMP protein and mRNA were seen following the addition of NAM to cells. These data support a role for NAM in cancer dissemination.

  16. Microwave circulator design

    CERN Document Server

    Linkhart, Douglas K

    2014-01-01

    Circulator design has advanced significantly since the first edition of this book was published 25 years ago. The objective of this second edition is to present theory, information, and design procedures that will enable microwave engineers and technicians to design and build circulators successfully. This resource contains a discussion of the various units used in the circulator design computations, as well as covers the theory of operation. This book presents numerous applications, giving microwave engineers new ideas about how to solve problems using circulators. Design examples are provided, which demonstrate how to apply the information to real-world design tasks.

  17. Force-dependent calcium signaling and its pathway of human neutrophils on P-selectin in flow.

    Science.gov (United States)

    Huang, Bing; Ling, Yingchen; Lin, Jiangguo; Du, Xin; Fang, Ying; Wu, Jianhua

    2017-02-01

    P-selectin engagement of P-selectin glycoprotein ligand-1 (PSGL-1) causes circulating leukocytes to roll on and adhere to the vascular surface, and mediates intracellular calcium flux, a key but unclear event for subsequent arresting firmly at and migrating into the infection or injured tissue. Using a parallel plate flow chamber technique and intracellular calcium ion detector (Fluo-4 AM), the intracellular calcium flux of firmly adhered neutrophils on immobilized P-selectin in the absence of chemokines at various wall shear stresses was investigated here in real time by fluorescence microscopy. The results demonstrated that P-selectin engagement of PSGL-1 induced the intracellular calcium flux of firmly adhered neutrophils in flow, increasing P-selectin concentration enhanced cellular calcium signaling, and, force triggered, enhanced and quickened the cytoplasmic calcium bursting of neutrophils on immobilized P-selectin. This P-selectin-induced calcium signaling should come from intracellular calcium release rather than extracellular calcium influx, and be along the mechano-chemical signal pathway involving the cytoskeleton, moesin and Spleen tyrosine kinase (Syk). These results provide a novel insight into the mechano-chemical regulation mechanism for P-selectin-induced calcium signaling of neutrophils in flow.

  18. Circulating Mitochondrial DAMPs Cause Inflammatory Responses to Injury

    Science.gov (United States)

    Zhang, Qin; Raoof, Mustafa; Chen, Yu; Sumi, Yuka; Sursal, Tolga; Junger, Wolfgang; Brohi, Karim; Itagaki, Kiyoshi; Hauser, Carl J.

    2009-01-01

    Injury causes a systemic inflammatory response syndrome (SIRS) clinically much like sepsis 1. Microbial pathogen-associated molecular patterns (PAMPs) activate innate immunocytes through pattern recognition receptors 2. Similarly, cellular injury can release endogenous damage-associated molecular patterns (DAMPs) that activate innate immunity 3. Mitochondria are evolutionary endosymbionts that were derived from bacteria 4 and so might bear bacterial molecular motifs. We show here that injury releases mitochondrial DAMPs (MTD) into the circulation with functionally important immune consequences. MTD include formyl peptides and mitochondrial DNA. These activate human neutrophils (PMN) through formyl peptide receptor-1 and TLR9 respectively. MTD promote PMN Ca2+ flux and phosphorylation of MAP kinases, thus leading to PMN migration and degranulation in vitro and in vivo. Circulating MTD can elicit neutrophil-mediated organ injury. Cellular disruption by trauma releases mitochondrial DAMPs with evolutionarily conserved similarities to bacterial PAMPs into the circulation. These can then signal through identical innate immune pathways to create a sepsis-like state. The release of such mitochondrial ‘enemies within’ by cellular injury is a key link between trauma, inflammation and SIRS. PMID:20203610

  19. Adhesion molecules involved in neutrophil recruitment during sepsis-induced acute kidney injury.

    Science.gov (United States)

    Herter, Jan M; Rossaint, Jan; Spieker, Tilmann; Zarbock, Alexander

    2014-01-01

    Acute kidney injury (AKI) is a common complication in critically ill patients and is associated with high mortality. Recruitment of neutrophils is a hallmark in the pathogenesis of AKI. Although ischemia-reperfusion injury (IRI) is a frequently used research model of AKI, the clinical relevance of IRI-induced AKI is limited. Epidemiologically, sepsis is the prevailing cause of kidney injury. However, it is still unknown whether these distinct entities of AKI share the same pathophysiological mechanisms. This study was initiated to investigate the molecular mechanisms of neutrophil recruitment into the kidney in a murine model of sepsis-induced AKI. By using a flow cytometry-based method, we show that the two β2-integrins Mac-1 and LFA-1 as well as E-selectin and P-selectin are involved in neutrophil recruitment into the kidney after induction of sepsis. The molecular mechanisms of neutrophil recruitment were further investigated using intravital microscopy, demonstrating that blocking one of these four molecules reduces the number of adherent leukocytes. This was accompanied by a renal upregulation of E-selectin, P-selectin and ICAM-1 (the counter-receptor of β2-integrins on endothelial cells) after sepsis induction. We conclude that blocking P-selectin, E-selectin, Mac-1 or LFA-1 protects mice from sepsis-induced AKI.

  20. Cleavage of CXCR1 on neutrophils disables bacterial killing in cystic fibrosis lung disease.

    Science.gov (United States)

    Hartl, Dominik; Latzin, Philipp; Hordijk, Peter; Marcos, Veronica; Rudolph, Carsten; Woischnik, Markus; Krauss-Etschmann, Susanne; Koller, Barbara; Reinhardt, Dietrich; Roscher, Adelbert A; Roos, Dirk; Griese, Matthias

    2007-12-01

    Interleukin-8 (IL-8) activates neutrophils via the chemokine receptors CXCR1 and CXCR2. However, the airways of individuals with cystic fibrosis are frequently colonized by bacterial pathogens, despite the presence of large numbers of neutrophils and IL-8. Here we show that IL-8 promotes bacterial killing by neutrophils through CXCR1 but not CXCR2. Unopposed proteolytic activity in the airways of individuals with cystic fibrosis cleaved CXCR1 on neutrophils and disabled their bacterial-killing capacity. These effects were protease concentration-dependent and also occurred to a lesser extent in individuals with chronic obstructive pulmonary disease. Receptor cleavage induced the release of glycosylated CXCR1 fragments that were capable of stimulating IL-8 production in bronchial epithelial cells via Toll-like receptor 2. In vivo inhibition of proteases by inhalation of alpha1-antitrypsin restored CXCR1 expression and improved bacterial killing in individuals with cystic fibrosis. The cleavage of CXCR1, the functional consequences of its cleavage, and the identification of soluble CXCR1 fragments that behave as bioactive components represent a new pathophysiologic mechanism in cystic fibrosis and other chronic lung diseases.

  1. Benefits of heat treatment to the protease packed neutrophil for proteome analysis: halting protein degradation.

    Science.gov (United States)

    Kennedy, Susan A; Scaife, Caitríona; Dunn, Michael J; Wood, Alfred E; Watson, R William G

    2011-06-01

    Neutrophils, cells of the innate immune system, contain an array of proteases and reactive oxygen species-generating enzymes that assist in controlling the invasion of bacteria and pathogens. The high content of intracellular proteolytic enzymes makes them difficult cells to work with as they can degrade proteins of potential interest. Here, we describe the benefits of heat treatment of neutrophils in reducing protein degradation for subsequent proteome analysis. Neutrophils isolated from four healthy volunteers were each divided into three aliquots and subjected to different preparation methods for 2-DE: (i) Heat treatment, (ii) resuspension in NP40 lysis buffer and (iii) resuspension in standard 2-DE lysis buffer. Representative spots found to be statistically significant between groups (pHeat-treated samples contained proteins in the high-molecular-weight range that were absent from NP40-treated samples. Moreover, NP40-treated samples showed an increase in spot number and volume at lower molecular weights suggestive of protein degradation. Incorporating heat treatment into sample preparation resulted in the identification of proteins that may not have previously been detected due to sample degradation, thus leading to a more comprehensive 2-DE map of the human neutrophil proteome.

  2. Mechanism of neutrophil recruitment to the lung after pulmonary contusion.

    Science.gov (United States)

    Hoth, J Jason; Wells, Jonathan D; Hiltbold, Elizabeth M; McCall, Charles E; Yoza, Barbara K

    2011-06-01

    Blunt chest trauma resulting in pulmonary contusion is a common but poorly understood injury. We previously demonstrated that lung contusion activates localized and systemic innate immune mechanisms and recruits neutrophils to the injured lung. We hypothesized that the innate immune and inflammatory activation of neutrophils may figure prominently in the response to lung injury. To investigate this, we used a model of pulmonary contusion in the mouse that is similar to that observed clinically in humans and evaluated postinjury lung function and pulmonary neutrophil recruitment. Comparisons were made between injured mice with and without neutrophil depletion. We further examined the role of chemokines and adhesion receptors in neutrophil recruitment to the injured lung. We found that lung injury and resultant physiological dysfunction after contusion were dependent on the presence of neutrophils in the alveolar space. We show that CXCL1, CXCL2/3, and CXCR2 are involved in neutrophil recruitment to the lung after injury and that intercellular adhesion molecule 1 is locally expressed and actively participates in this process. Injured gp91-deficient mice showed improved lung function, indicating that oxidant production by neutrophil NADPH oxidase mediates lung dysfunction after contusion. These data suggest that both neutrophil presence and function are required for lung injury after lung contusion.

  3. Human filarial Wolbachia lipopeptide directly activates human neutrophils in vitro.

    Science.gov (United States)

    Tamarozzi, F; Wright, H L; Johnston, K L; Edwards, S W; Turner, J D; Taylor, M J

    2014-10-01

    The host inflammatory response to the Onchocerca volvulus endosymbiont, Wolbachia, is a major contributing factor in the development of chronic pathology in humans (onchocerciasis/river blindness). Recently, the toll-like pattern recognition receptor motif of the major inflammatory ligands of filarial Wolbachia, membrane-associated diacylated lipoproteins, was functionally defined in murine models of pathology, including mediation of neutrophil recruitment to the cornea. However, the extent to which human neutrophils can be activated in response to this Wolbachia pattern recognition motif is not known. Therefore, the responses of purified peripheral blood human neutrophils to a synthetic N-terminal diacylated lipopeptide (WoLP) of filarial Wolbachia peptidoglycan-associated lipoprotein (PAL) were characterized. WoLP exposure led to a dose-dependent activation of healthy, human neutrophils that included gross morphological alterations and modulation of surface expressed integrins involved in tethering, rolling and extravasation. WoLP exposure induced chemotaxis but not chemokinesis of neutrophils, and secretion of the major neutrophil chemokine, interleukin 8. WoLP also induced and primed the respiratory burst, and enhanced neutrophil survival by delay of apoptosis. These results indicate that the major inflammatory motif of filarial Wolbachia lipoproteins directly activates human neutrophils in vitro and promotes a molecular pathway by which human neutrophils are recruited to sites of Onchocerca parasitism.

  4. Physiology of the fetal circulation.

    Science.gov (United States)

    Kiserud, Torvid

    2005-12-01

    Our understanding of fetal circulatory physiology is based on experimental animal data, and this continues to be an important source of new insight into developmental mechanisms. A growing number of human studies have investigated the human physiology, with results that are similar but not identical to those from animal studies. It is time to appreciate these differences and base more of our clinical approach on human physiology. Accordingly, the present review focuses on distributional patterns and adaptational mechanisms that were mainly discovered by human studies. These include cardiac output, pulmonary and placental circulation, fetal brain and liver, venous return to the heart, and the fetal shunts (ductus venosus, foramen ovale and ductus arteriosus). Placental compromise induces a set of adaptational and compensational mechanisms reflecting the plasticity of the developing circulation, with both short- and long-term implications. Some of these aspects have become part of the clinical physiology of today with consequences for surveillance and treatment.

  5. Temporal adaptation of neutrophil oxidative responsiveness to n-formyl-methionyl-leucyl-phenylalanine. Acceleration by granulocyte-macrophage colony stimulating factor.

    Science.gov (United States)

    English, D; Broxmeyer, H E; Gabig, T G; Akard, L P; Williams, D E; Hoffman, R

    1988-10-01

    This investigation was undertaken to clarify the mechanism by which purified recombinant human granulocyte-macrophage colony stimulating factor (GM-CSF) potentiates neutrophil oxidative responses triggered by the chemotactic peptide, FMLP. Previous studies have shown that GM-CSF priming of neutrophil responses to FMLP is induced relatively slowly, requiring 90 to 120 min of incubation in vitro, is not associated with increased levels of cytoplasmic free Ca2+, but is associated with up-regulation of cell-surface FMLP receptors. We have confirmed these findings and further characterized the process of GM-CSF priming. We found that the effect of GM-CSF on neutrophil oxidative responsiveness was induced in a temperature-dependent manner and was not reversed when the cells were washed extensively to remove the growth factor before stimulation with FMLP. Extracellular Ca2+ was not required for functional enhancement by GM-CSF and GM-CSF alone effected no detectable alteration in the 32P-labeled phospholipid content of neutrophils during incubation in vitro. Our data indicate that GM-CSF exerts its influence on neutrophils by accelerating a process that occurs spontaneously and results in up-regulation of both cell-surface FMLP receptors and oxidative responsiveness to FMLP. Thus, the results demonstrate that, with respect to oxidative activation, circulating endstage polymorphonuclear leukocytes are nonresponsive or hyporesponsive to FMLP; functional responsiveness increases dramatically as surface FMLP receptors are gradually deployed after the cells leave the circulation. Thus, as neutrophils mature, their responsiveness to FMLP changes in a manner which may be crucial for efficient host defense. At 37 degrees C, this process is markedly potentiated by GM-CSF. We conclude that endogenous GM-CSF, released systemically or at sites of infection and inflammation, potentially plays an important role in host defense by accelerating functional maturation of responding

  6. Proinflammatory mediators stimulate neutrophil-directed angiogenesis.

    LENUS (Irish Health Repository)

    McCourt, M

    2012-02-03

    BACKGROUND: Vascular endothelial growth factor (VEGF; vascular permeability factor) is one of the most potent proangiogenic cytokines, and it plays a central role in mediating the process of angiogenesis or new blood vessel formation. Neutrophils (PMNs) recently have been shown to produce VEGF. HYPOTHESIS: The acute inflammatory response is a potent stimulus for PMN-directed angiogenesis. METHODS: Neutrophils were isolated from healthy volunteers and stimulated with lipopolysaccharide (LPS), tumor necrosis factor alpha (TNF-alpha), interleukin 6 (IL-6), and anti-human Fas monoclonal antibody. Culture supernatants were assayed for VEGF using enzyme-linked immunosorbent assays. Culture supernatants from LPS- and TNF-alpha-stimulated PMNs were then added to human umbilical vein endothelial cells and human microvessel endothelial cells and assessed for endothelial cell proliferation using 5-bromodeoxyuridine labeling. Tubule formation was also assessed on MATRIGEL basement membrane matrix. Neutrophils were lysed to measure total VEGF release, and VEGF expression was detected using Western blot analysis. RESULTS: Lipopolysaccharide and TNF-alpha stimulation resulted in significantly increased release of PMN VEGF (532+\\/-49 and 484+\\/-80 pg\\/mL, respectively; for all, presented as mean +\\/- SEM) compared with control experiments (32+\\/-4 pg\\/mL). Interleukin 6 and Fas had no effect. Culture supernatants from LPS- and TNF-alpha-stimulated PMNs also resulted in significant increases (P<.005) in macrovascular and microvascular endothelial cell proliferation and tubule formation. Adding anti-human VEGF-neutralizing polyclonal antibody to stimulated PMN supernatant inhibited these effects. Total VEGF release following cell lysis and Western blot analysis suggests that the VEGF is released from an intracellular store. CONCLUSION: Activated human PMNs are directly angiogenic by releasing VEGF, and this has important implications for inflammation, capillary leak syndrome

  7. LFA-1 and Mac-1 define characteristically different intralumenal crawling and emigration patterns for monocytes and neutrophils in situ.

    Science.gov (United States)

    Sumagin, Ronen; Prizant, Hen; Lomakina, Elena; Waugh, Richard E; Sarelius, Ingrid H

    2010-12-01

    To exit blood vessels, most (∼80%) of the lumenally adhered monocytes and neutrophils crawl toward locations that support transmigration. Using intravital confocal microscopy of anesthetized mouse cremaster muscle, we separately examined the crawling and emigration patterns of monocytes and neutrophils in blood-perfused unstimulated or TNF-α-activated venules. Most of the interacting cells in microvessels are neutrophils; however, in unstimulated venules, a greater percentage of the total monocyte population is adherent compared with neutrophils (58.2 ± 6.1% versus 13.6 ± 0.9%, adhered/total interacting), and they crawl for significantly longer distances (147.3 ± 13.4 versus 61.8 ± 5.4 μm). Intriguingly, after TNF-α activation, monocytes crawled for significantly shorter distances (67.4 ± 9.6 μm), resembling neutrophil crawling. Using function-blocking Abs, we show that these different crawling patterns were due to CD11a/CD18 (LFA-1)- versus CD11b/CD18 (Mac-1)-mediated crawling. Blockade of either Mac-1 or LFA-1 revealed that both LFA-1 and Mac-1 contribute to monocyte crawling; however, the LFA-1-dependent crawling in unstimulated venules becomes Mac-1 dependent upon inflammation, likely due to increased expression of Mac-1. Mac-1 alone was responsible for neutrophil crawling in both unstimulated and TNF-α-activated venules. Consistent with the role of Mac-1 in crawling, Mac-1 block (compared with LFA-1) was also significantly more efficient in blocking TNF-α-induced extravasation of both monocytes and neutrophils in cremaster tissue and the peritoneal cavity. Thus, mechanisms underlying leukocyte crawling are important in regulating the inflammatory responses by regulating the numbers of leukocytes that transmigrate.

  8. Ranitidine improves postoperative monocyte and neutrophil function

    DEFF Research Database (Denmark)

    Nielsen, Hans Jørgen; Nielsen, H; Jensen, S;

    1994-01-01

    BACKGROUND: The histamine H2-receptor antagonist ranitidine hydrochloride has been shown to improve trauma-, blood transfusion-, and sepsis-induced immunosuppression. OBJECTIVE: To evaluate the effect of ranitidine on postoperative impairment in monocyte and neutrophil function. METHODS: Twenty......-four patients undergoing major elective abdominal surgery were randomized to receive adjuvant treatment with ranitidine hydrochloride (100 mg) administered twice a day intravenously from skin incision for 4 days, followed by oral ranitidine hydrochloride (150 mg) administered twice a day for 5 days (n = 11...

  9. Glutamine-Loaded Liposomes: Preliminary Investigation, Characterization, and Evaluation of Neutrophil Viability.

    Science.gov (United States)

    Costa, Larissa Chaves; Souza, Bárbara Nayane Rosário Fernandes; Almeida, Fábio Fidélis; Lagranha, Cláudia Jacques; Cadena, Pabyton Gonçalves; Santos-Magalhães, Nereide Stela; Lira-Nogueira, Mariane Cajubá de Britto

    2016-04-01

    Glutamine has received attention due to its ability to ameliorate the immune system response. Once conventional liposomes are readily recognized and captured by immune system cells, the encapsulation of glutamine into those nanosystems could be an alternative to reduce glutamine dosage and target then to neutrophils. Our goals were to nanoencapsulate glutamine into conventional liposomes (Gln-L), develop an analytical high-performance liquid chromatography (HPLC) method for its quantification, and evaluate the viability of neutrophils treated with Gln-L. Liposomes were prepared using the thin-film hydration technique followed by sonication and characterized according to pH, mean size, zeta potential, and drug encapsulation efficiency (EE%). We also aimed to study the effect of liposomal constituent concentrations on liposomal characteristics. The viability of neutrophils was assessed using flow cytometry after intraperitoneal administration of free glutamine (Gln), Gln-L, unloaded-liposome (UL), and saline solution as control (C) in healthy Wistar rats. The selected liposomal formulation had a mean vesicle size of 114.65 ± 1.82 nm with a polydispersity index of 0.30 ± 0.00, a positive surface charge of 36.30 ± 1.38 mV, and an EE% of 39.49 ± 0.74%. The developed chromatographic method was efficient for the quantification of encapsulated glutamine, with a retention time at 3.8 min. A greater viability was observed in the group treated with glutamine encapsulated compared to the control group (17%), although neutrophils remain viable in all groups. Thus, glutamine encapsulated into liposomes was able to increase the number of viable neutrophils at low doses, thereby representing a promising strategy for the treatment of immunodeficiency conditions.

  10. The number of circulating CD14+ cells is related to infarct size and postinfarct volumes in ST segment elevation myocardial infarction but not non-ST segment elevation myocardial infarction

    Science.gov (United States)

    Montange, Damien; Davani, Siamak; Deschaseaux, Frédéric; Séronde, Marie France; Chopard, Romain; Schiele, François; Jehl, Jérome; Bassand, Jean Pierre; Kantelip, Jean-Pierre; Meneveau, Nicolas

    2012-01-01

    OBJECTIVE: To determine the relationship between the number of CD14+ cells, myocardial infarct (MI) size and left ventricular (LV) volumes in ST segment elevation MI (STEMI) and non-ST segment elevation MI (NSTEMI) patients. METHODS: A total of 62 patients with STEMI (n=34) or NSTEMI (n=28) were enrolled. The number of CD14+ cells was assessed at admission. Infarct size, left ventricular ejection fraction (LVEF) and LV volumes were measured using magnetic resonance imaging five days after MI and six months after MI. Results: In STEMI patients, the number of CD14+ cells was positively and significantly correlated with infarct size at day 5 (r=0.40; P=0.016) and after six months (r=0.34; P=0.047), negatively correlated with LVEF at day 5 (r=−0.50; P=0.002) and after six months (r=−0.46; P=0.005) and positively correlated with end-diastolic (r=0.38; P=0.02) and end-systolic (r=0.49; P=0.002) volumes after six months. In NSTEMI patients, no significant correlation was found between the number of CD14+ cells and infarct size, LVEF or LV volumes at day 5 or after six months. CONCLUSIONS: The number of CD14+ cells at admission was associated with infarct size and LV remodelling in STEMI patients with large infarct size, whereas in NSTEMI patients, no relationship was observed between numbers of CD14+ cells and LV remodelling. PMID:23620701

  11. Mountains and Tropical Circulation

    Science.gov (United States)

    Naiman, Z.; Goodman, P. J.; Krasting, J. P.; Malyshev, S.; Russell, J. L.; Stouffer, R. J.

    2015-12-01

    Observed tropical convection exhibits zonal asymmetries that strongly influence spatial precipitation patterns. The drivers of changes to this zonally-asymmetric Walker circulation on decadal and longer timescales have been the focus of significant recent research. Here we use two state-of-the-art earth system models to explore the impact of earth's mountains on the Walker circulation. When all land-surface topography is removed, the Walker circulation weakens by 33-59%. There is a ~30% decrease in global, large-scale upward vertical wind velocities in the middle of the troposphere, but only minor changes in global average convective mass flux, precipitation, surface and sea-surface temperatures. The zonally symmetric Hadley circulation is also largely unchanged. Following the spatial pattern of changes to large-scale vertical wind velocities, precipitation becomes less focused over the tropics. The weakening of the Walker circulation, but not the Hadley circulation, is similar to the behavior of climate models during radiative forcing experiments: in our simulations, the weakening is associated with changes in vertical wind velocities, rather than the hydrologic cycle. These results indicate suggest that mountain heights may significantly influence the Walker circulation on geologic time scales, and observed changes in tropical precipitation over millions of years may have been forced by changes in tropical orography.

  12. Exercício abaixo do limiar anaeróbio aumenta as atividades fagocítica e microbicida de neutrófilos em ratos Wistar Exercise below the anaerobic threshold increases phagocytic and microbicide activities of neutrophils in Wistar rats

    Directory of Open Access Journals (Sweden)

    Juliana Bombarda

    2009-02-01

    Full Text Available OBJETIVO: Investigar o efeito de uma sessão de exercício abaixo do limiar anaeróbio sobre as funções de neutrófilos e monócitos circulantes em ratos Wistar. MATERIAL E MÉTODO: Trata-se de um delineamento experimental com um pós-teste em que os sujeitos do grupo experimental exercitaram-se na água por 30 minutos enquanto controles não foram submetidos a qualquer intervenção. A atividade funcional dos fagócitos circulantes foi avaliada por ensaio de fagocitose de Saccharomyces cerevisiae e pelo teste de redução de nitroazul de tetrazólio (NBT. Para comparação entre as médias dos grupos, utilizaram-se testes t para amostras independentes com p OBJECTIVE: To assess the effect of a single session of exercise conducted below the anaerobic threshold on the functions of neutrophils and circulating monocytes in Wistar rats. MATERIAL AND METHOD: This study had an experimental design with a single post-test in which subjects of the experimental group exercised in water for 30 minutes, whereas the control group was not submitted to any intervention. Functional capacity of circulating phagocytes was assessed by means of a phagocytosis assay of Saccharomyces cerevisiae and a nitro blue tetrazolium (NBT reduction test. To compare means between groups, t tests for independent samples were used with p set at < 0.05. RESULTS: There were no significant differences as to the total and differential number of leucocytes between groups. Nonetheless, not only did the neutrophils of the experimental group phagocyte more S. cerevisiae (p = 0.005, but they also reduced NBT more efficiently (p = 0.018 in comparison with control subjects. No significant differences in these functional activities were observed in circulating monocytes. CONCLUSION: The exercise performed below the anaerobic threshold was sufficient to increase both phagocytic and microbicide activities of neutrophils in animal model, but the same protocol did not yield similar results for

  13. Shielding of a lipooligosaccharide IgM epitope allows evasion of neutrophil-mediated killing of an invasive strain of nontypeable Haemophilus influenzae.

    Science.gov (United States)

    Langereis, Jeroen D; Weiser, Jeffrey N

    2014-07-22

    Nontypeable Haemophilus influenzae is a frequent cause of noninvasive mucosal inflammatory diseases but may also cause invasive diseases, such as sepsis and meningitis, especially in children and the elderly. Infection by nontypeable Haemophilus influenzae is characterized by recruitment of neutrophilic granulocytes. Despite the presence of a large number of neutrophils, infections with nontypeable Haemophilus influenzae are often not cleared effectively by the antimicrobial activity of these immune cells. Herein, we examined how nontypeable Haemophilus influenzae evades neutrophil-mediated killing. Transposon sequencing (Tn-seq) was used on an isolate resistant to neutrophil-mediated killing to identify genes required for its survival in the presence of human neutrophils and serum, which provided a source of complement and antibodies. Results show that nontypeable Haemophilus influenzae prevents complement-dependent neutrophil-mediated killing by expression of surface galactose-containing oligosaccharide structures. These outer-core structures block recognition of an inner-core lipooligosaccharide epitope containing glucose attached to heptose HepIII-β1,2-Glc by replacement with galactose attached to HepIII or through shielding HepIII-β1,2-Glc by phase-variable attachment of oligosaccharide chain extensions. When the HepIII-β1,2-Glc-containing epitope is expressed and exposed, nontypeable Haemophilus influenzae is opsonized by naturally acquired IgM generally present in human serum and subsequently phagocytosed and killed by human neutrophils. Clinical nontypeable Haemophilus influenzae isolates containing galactose attached to HepIII that are not recognized by this IgM are more often found to cause invasive infections. Importance: Neutrophils are white blood cells that specialize in killing pathogens and are recruited to sites of inflammation. However, despite the presence of large numbers of neutrophils in the middle ear cavity and lungs of patients with

  14. A novel immune regulatory function of neutrophils in rhinovirus infections

    NARCIS (Netherlands)

    Tang, Francesca; Hansbro, Phil; Burgess, Janette; Baines, Katherine; Oliver, Brian

    2015-01-01

    Rationale: Rhinovirus (RV) is a major precipitant of asthma exacerbations. During lung infections there is elevated neutrophilic inflammation which is associated with more severe asthma symptoms. Previously, we found that neutrophils respond to viral mimetics but not live RV. Here we investigated if

  15. Early diagnostic method for sepsis based on neutrophil MR imaging

    Directory of Open Access Journals (Sweden)

    Shanhua Han

    2015-06-01

    Conclusion: Mouse and human neutrophils could be more effectively labelled by Mannan-coated SPION in vitro than Feridex. Sepsis analog neutrophils labelled by Mannan-coated SPIONs could be efficiently detected on MR images, which may serve as an early diagnostic method for sepsis.

  16. Ascorbate recycling in human neutrophils: Induction by bacteria

    OpenAIRE

    Wang, Yaohui; Russo, Thomas A.; Kwon, Oran; Chanock, Stephen; Rumsey, Steven C.; Levine, Mark

    1997-01-01

    Ascorbate (vitamin C) recycling occurs when extracellular ascorbate is oxidized, transported as dehydroascorbic acid, and reduced intracellularly to ascorbate. We investigated microorganism induction of ascorbate recycling in human neutrophils and in microorganisms themselves. Ascorbate recycling was determined by measuring intracellular ascorbate accumulation. Ascorbate recycling in neutrophils was induced by both Gram-positive and Gram-negative pathogenic bacteria, and the fungal pathogen C...

  17. Intracellular localization of VAMP-1 protein in human neutrophils.

    Science.gov (United States)

    Nabokina, S M

    2001-02-01

    We studied the intracellular localization of vesicle-associated membrane protein VAMP-1 in human neutrophils. VAMP-1 was associated with membranes of gelatinase and specific secretory granules rapidly mobilized during exocytosis. VAMP-1 probably acts as a component of the SNARE complex during exocytosis of gelatinase and specific granules in human neutrophils.

  18. Killing of Mycobacterium tuberculosis by neutrophils: a nonoxidative process.

    Science.gov (United States)

    Jones, G S; Amirault, H J; Andersen, B R

    1990-09-01

    To determine the role of oxygen radicals in the killing of Mycobacterium tuberculosis by neutrophils, the effects of free-radical inhibitors and enzymes, catalase, superoxide dismutase, taurine, deferoxamine, and histidine were evaluated. Changes in the viability of M. tuberculosis were determined by agar plate colony counts and a radiometric assay. No impairment in killing was seen with any of the inhibitors or enzymes. Patients with chronic granulomatous disease (CGD) have a defect in the NADPH oxidase pathway, causing their neutrophils to be unable to generate oxygen radicals. If these radicals are involved in killing, then CGD neutrophils should be less effective killers of M. tuberculosis than normal neutrophils. There was no evidence by either measure of M. tuberculosis viability that CGD neutrophils were less bactericidal than normal neutrophils. Killing by normal neutrophils was also effective in the absence of serum. These results lead to the conclusion that the mechanism by which M. tuberculosis is killed by neutrophils is independent of the oxygen metabolic burst.

  19. Quercetin inhibits degranulation and superoxide generation in PMA stimulated neutrophils

    OpenAIRE

    2012-01-01

    Activated neutrophils represent the main source of myeloperoxidase (MPO), superoxide (SO) and subsequently derived oxygen metabolites. They have important microbicidal activities, however in inflammatory conditions they may secondarily attack surrounding tissues. Overproduction of reactive oxygen species, prolonged or excessive liberation of MPO and other effective yet also toxic substances from neutrophils may participate in disturbed apoptosis, intensify the inflammatory processes and resul...

  20. Intergrin-dependent neutrophil migration in the injured mouse cornea

    Science.gov (United States)

    As an early responder to an inflammatory stimulus, neutrophils must exit the vasculature and migrate through the extravascular tissue to the site of insult, which is often remote from the point of extravasation. Following a central epithelial corneal abrasion, neutrophils recruited from the peripher...

  1. Synchronisation of glycolytic oscillations in a suspension of human neutrophils

    DEFF Research Database (Denmark)

    Brasen, Jens Christian; Poulsen, Allan K.; Olsen, Lars Folke

    Neutrophils are known to be able to synchronize their production of superoxide. We show that glycolysis is also synchronized in human neutrophils being in suspension and suggest that oscillations in glycolysis are driving the pulsatile production of superoxide. The synchronising agent remains so...

  2. Activation of the Small GTPase Rap1 in Human Neutrophils

    NARCIS (Netherlands)

    M'Rabet, Laura; Coffer, P.J.; Zwartkruis, G.J.T.; Franke, Barbara; Segal, Anthony W.; Koenderman, L.; Bos, J.L.

    2002-01-01

    The small GTPase Rap1 is highly expressed in human neutrophils, but its function is largely unknown. Using the Rap1- binding domain of RalGDS (RalGDS-RBD) as an activationspecific probe for Rap1, we have investigated the regulation of Rap1 activity in primary human neutrophils. We found that a varie

  3. Resistance of Neisseria gonorrhoeae to neutrophils

    Directory of Open Access Journals (Sweden)

    M. Brittany eJohnson

    2011-04-01

    Full Text Available Infection with the human-specific bacterial pathogen Neisseria gonorrhoeae triggers a potent, local inflammatory response driven by polymorphonuclear leukocytes (neutrophils or PMNs. PMNs are terminally differentiated phagocytic cells that are a vital component of the host innate immune response and are the first responders to bacterial and fungal infections. PMNs possess a diverse arsenal of components to combat microorganisms, including the production of reactive oxygen species and release of degradative enzymes and antimicrobial peptides. Despite numerous PMNs at the site of gonococcal infection, N. gonorrhoeae can be cultured from the PMN-rich exudates of individuals with acute gonorrhea, indicating that some bacteria resist killing by neutrophils. The contribution of PMNs to gonorrheal pathogenesis has been modeled in vivo by human male urethral challenge and murine female genital inoculation and in vitro using isolated primary PMNs or PMN-derived cell lines. These systems reveal that some gonococci survive and replicate within PMNs and suggest that gonococci defend themselves against PMNs in two ways: they express virulence factors that defend against PMNs’ oxidative and non-oxidative antimicrobial components, and they modulate the ability of PMNs to phagocytose gonococci and to release antimicrobial components. In this review, we will highlight the varied and complementary approaches used by N. gonorrhoeae to resist clearance by human PMNs, with an emphasis on gonococcal gene products that modulate bacterial-PMN interactions. Understanding how some gonococci survive exposure to PMNs will help guide future initiatives for combating gonorrheal disease.

  4. Interaction of natural killer cells with neutrophils exerts a significant antitumor immunity in hematopoietic stem cell transplantation recipients.

    Science.gov (United States)

    Ueda, Ryosuke; Narumi, Kenta; Hashimoto, Hisayoshi; Miyakawa, Reina; Okusaka, Takuji; Aoki, Kazunori

    2016-01-01

    Autologous hematopoietic stem cell transplantation (HSCT) can induce a strong antitumor immunity by homeostatic proliferation (HP) of T cells and suppression of regulatory T cells following preconditioning-induced lymphopenia. However, the role of innate immunity including natural killer (NK) cells is still not understood. Here, first, we examined whether NK cells exert an antitumor effect after syngeneic HSCT in a murine colon cancer model. Flow cytometry showed that NK cells as well as T cells rapidly proliferated after HSCT, and the frequency of mature NK cells was increased in tumor during HP. Furthermore, NK cells undergoing HP were highly activated, which contributed to substantial tumor suppression. Then, we found that a large number of neutrophils accumulated in tumor early after syngeneic HSCT. It was recently reported that neutrophil-derived mediators modulate NK cell effector functions, and so we examined whether the neutrophils infiltrated in tumor are associated with NK cell-mediated antitumor effect. The depletion of neutrophils significantly impaired an activation of NK cells in tumor and increased the fraction of proliferative NK cells accompanied by a decrease in NK cell survival. The results suggested that neutrophils in tumor prevent NK cells from activation-induced cell death during HP, thus leading to a significant antitumor effect by NK cells. This study revealed a novel aspect of antitumor immunity induced by HSCT and may contribute to the development of an effective therapeutic strategy for cancer using HSCT.

  5. Olfactomedin 4 defines a subset of human neutrophils

    DEFF Research Database (Denmark)

    Clemmensen, Stine N; Bohr, Christina T; Rørvig, Sara;

    2012-01-01

    OLFM4 was identified initially as a gene highly induced in myeloid stem cells by G-CSF treatment. A bioinformatics method using a global meta-analysis of microarray data predicted that OLFM4 would be associated with specific granules in human neutrophils. Subcellular fractionation of peripheral...... blood neutrophils demonstrated complete colocalization of OLFM4 with the specific granule protein NGAL, and stimulation of neutrophils with PMA resulted in corelease of NGAL and OLFM4, proving that OLFM4 is a genuine constituent of neutrophil-specific granules. In accordance with this, OLFM4 mRNA peaked...... at the MY/MM stage of maturation. OLFM4 was, however, present in only 20-25% of peripheral blood neutrophils, as determined by immunocytochemistry and flow cytometry, whereas mRNA for OLFM4 was present in all MY/MM, indicating post-transcriptional regulation as a basis for the heterogeneous expression...

  6. Paradoxical Roles of the Neutrophil in Sepsis: Protective and Deleterious

    Science.gov (United States)

    Sônego, Fabiane; Castanheira, Fernanda Vargas e Silva; Ferreira, Raphael Gomes; Kanashiro, Alexandre; Leite, Caio Abner Vitorino Gonçalves; Nascimento, Daniele Carvalho; Colón, David Fernando; Borges, Vanessa de Fátima; Alves-Filho, José Carlos; Cunha, Fernando Queiróz

    2016-01-01

    Sepsis, an overwhelming inflammatory response syndrome secondary to infection, is one of the costliest and deadliest medical conditions worldwide. Neutrophils are classically considered to be essential players in the host defense against invading pathogens. However, several investigations have shown that impairment of neutrophil migration to the site of infection, also referred to as neutrophil paralysis, occurs during severe sepsis, resulting in an inability of the host to contain and eliminate the infection. On the other hand, the neutrophil antibacterial arsenal contributes to tissue damage and the development of organ dysfunction during sepsis. In this review, we provide an overview of the main events in which neutrophils play a beneficial or deleterious role in the outcome of sepsis. PMID:27199981

  7. Exosomes Mediate LTB4 Release during Neutrophil Chemotaxis.

    Directory of Open Access Journals (Sweden)

    Ritankar Majumdar

    2016-01-01

    Full Text Available Leukotriene B4 (LTB4 is secreted by chemotactic neutrophils, forming a secondary gradient that amplifies the reach of primary chemoattractants. This strategy increases the recruitment range for neutrophils and is important during inflammation. Here, we show that LTB4 and its synthesizing enzymes localize to intracellular multivesicular bodies that, upon stimulation, release their content as exosomes. Purified exosomes can activate resting neutrophils and elicit chemotactic activity in a LTB4 receptor-dependent manner. Inhibition of exosome release leads to loss of directional motility with concomitant loss of LTB4 release. Our findings establish that the exosomal pool of LTB4 acts in an autocrine fashion to sensitize neutrophils towards the primary chemoattractant, and in a paracrine fashion to mediate the recruitment of neighboring neutrophils in trans. We envision that this mechanism is used by other signals to foster communication between cells in harsh extracellular environments.

  8. Toll-like receptor responses in IRAK-4-deficient neutrophils.

    Science.gov (United States)

    van Bruggen, Robin; Drewniak, Agata; Tool, Anton T J; Jansen, Machiel; van Houdt, Michel; Geissler, Judy; van den Berg, Timo K; Chapel, Helen; Kuijpers, Taco W

    2010-01-01

    Human neutrophils were found to express all known Toll-like receptors (TLRs) except TLR3 and TLR7. IRAK-4-deficient neutrophils were tested for their responsiveness to various TLR ligands. Essentially all TLR responses in neutrophils, including the induction of reactive oxygen species generation, adhesion, chemotaxis and IL-8 secretion, were found to be dependent on IRAK-4. Surprisingly, the reactivity towards certain established TLR ligands, imiquimod and ODN-CpG, was unaffected by IRAK-4 deficiency, demonstrating their activity is independent of TLR. TLR-4-dependent signaling in neutrophils was totally dependent on IRAK-4 without any major TRIF-mediated contribution. We did not observe any defects in killing capacity of IRAK-4-deficient neutrophils for Staphylococcus aureus, Escherichia coli and Candida albicans, suggesting that microbial killing is primarily TLR independent.

  9. Reverse Migration of Neutrophils: Where, When, How, and Why?

    Science.gov (United States)

    Nourshargh, Sussan; Renshaw, Stephen A; Imhof, Beat A

    2016-05-01

    Neutrophil migration to injured and pathogen-infected tissues is a fundamental component of innate immunity. An array of cellular and molecular events mediate this response to collectively guide neutrophils out of the vasculature and towards the core of the ensuing inflammatory reaction where they exert effector functions. Advances in imaging modalities have revealed that neutrophils can also exhibit motility away from sites of inflammation and injury, although it is unclear under what circumstances this reverse migration is a physiological protective response, and when it has pathophysiological relevance. Here we review different types of neutrophil reverse migration and discuss the current understanding of the associated mechanisms. In this context we propose clarifications to the existing terminology used to describe the many facets of neutrophil reverse migration.

  10. Learning Circulant Sensing Kernels

    Science.gov (United States)

    2014-03-01

    learned dictionaries. Examples of analytic dictionaries include the discrete cosine basis, various wavelets bases , as well as tight frames. Some of them...Compressive sensing based high resolution channel estimation for OFDM system. To appear in IEEE Journal of Selected Topics in Signal Processing, Special...theoretical and computational properties to a (partial) circulant matrix of the same size, our discussions below are based exclusively on the circulant

  11. Structural divergence of GPI-80 in activated human neutrophils.

    Science.gov (United States)

    Nitto, Takeaki; Takeda, Yuji; Yoshitake, Hiroshi; Sendo, Fujiro; Araki, Yoshihiko

    2007-07-27

    GPI-80 is a glycosylphosphatidylinositol (GPI)-anchored protein that is mainly expressed in human neutrophils. Previous studies using 3H9, a monoclonal antibody (mAb) against GPI-80, suggested that GPI-80 regulates leukocyte adherence and migration through Mac-1. GPI-80, which is anchored at the plasma membrane in resting neutrophils, moves into the pseudopodia and is released from activated human neutrophils. Here, we demonstrate that neutrophil activation affects GPI-80 dynamics using a new anti-GPI-80 mAb, designated 4D4, which is directed against the form of GPI-80 found on resting human neutrophils. Similar to 3H9, 4D4 influences Mac-1-dependent neutrophil adhesion. Treatment of purified GPI-80 with periodic acid and trypsin indicated that 3H9 and 4D4 recognize peptide and carbohydrate moieties, respectively. Stimulation with fMLP decreased the binding of 4D4 to GPI-80 on the neutrophil surface but increased the overall expression of GPI-80, as visualized by the 3H9 signal. Confocal laser microscopy revealed the 4D4 signal mainly on cell bodies and at a low level on pseudopodia during migration toward increasing concentrations of fMLP, whereas the 3H9 signal was observed in both areas. In addition, soluble GPI-80 released from activated neutrophils did not bind 4D4. These results suggest that there are two populations of GPI-80 that differ in the ability to bind 4D4. The 4D4-recognized form may regulate Mac-1-dependent neutrophil adhesion, and may subsequently be converted to a 4D4-unrecognized form during neutrophil activation.

  12. Visceral leishmaniasis patients display altered composition and maturity of neutrophils as well as impaired neutrophil effector functions

    Directory of Open Access Journals (Sweden)

    Endalew Yizengaw

    2016-11-01

    Full Text Available Immunologically, active visceral leishmaniasis (VL is characterised by profound immunosuppression, severe systemic inflammatory responses and an impaired capacity to control parasite replication. Neutrophils are highly versatile cells, which play a crucial role in the induction as well as the resolution of inflammation, the control of pathogen replication and the regulation of immune responses. Neutrophil functions have been investigated in human cutaneous leishmaniasis, however, their role in human visceral leishmaniasis is poorly understood.In the present study we evaluated the activation status and effector functions of neutrophils in patients with active VL and after successful anti-leishmanial treatment. Our results show that neutrophils are highly activated and have degranulated; high levels of arginase, myeloperoxidase and elastase, all contained in neutrophils’ granules, were found in the plasma of VL patients. In addition, we show that a large proportion of these cells are immature. We also analysed effector functions of neutrophils that are essential for pathogen clearance and show that neutrophils have an impaired capacity to release neutrophil extracellular traps, produce reactive oxygen species and phagocytose bacterial particles, but not Leishmania parasites.Our results suggest that impaired effector functions, increased activation and immaturity of neutrophils play a key role in the pathogenesis of VL.

  13. CXC Receptor 1 and 2 and Neutrophil Elastase Inhibitors Alter Radiation-induced Lung Disease in the Mouse

    Energy Technology Data Exchange (ETDEWEB)

    Fox, Jessica [Department of Medicine and the Meakins-Christie Laboratories, McGill University, Montreal, Quebec (Canada); Haston, Christina K., E-mail: christina.haston@mcgill.ca [Department of Medicine and the Meakins-Christie Laboratories, McGill University, Montreal, Quebec (Canada)

    2013-01-01

    Purpose: We previously reported increased numbers of neutrophils to be associated with the development of the radiation-induced lung responses of alveolitis (pneumonitis) and fibrosis in mice. In the present study we investigated whether CXC receptor 1 and 2 antagonism with DF2156A, a small molecule inhibitor of neutrophil chemotaxis, or the neutrophil elastase inhibitor sivelestat decreases the lung response to irradiation. Methods and Materials: KK/HIJ mice received 14 Gy whole-thorax irradiation, and a subset of them received drug treatment 3 times per week from the day of irradiation until they were killed because of respiratory distress symptoms. Results: Irradiated mice receiving sivelestat survived 18% longer than did mice receiving radiation alone (73 vs 60 days for female mice, 91 vs 79 days for male mice), whereas postirradiation survival times did not differ between the group of mice receiving DF2156A and the radiation-only group. The numbers of neutrophils in lung tissue and in bronchoalveolar lavage fluid did not differ among groups of irradiated mice, but they significantly exceeded the levels in unirradiated control mice. The extent of alveolitis, assessed histologically, did not differ between irradiated mice treated with either drug and those receiving radiation alone, when assessed at the end of the experiment, but it was significantly reduced, as were the neutrophil measures, in sivelestat-treated mice at the common kill time of 60 days after irradiation. Mice treated with radiation and DF2156A developed significantly less fibrosis than did mice receiving radiation alone, and this difference was associated with decreased expression of interleukin-13 in lung tissue. Conclusions: We conclude that neutrophil elastase inhibition affects alveolitis and prolongs survival, whereas CXCR1/2 antagonism reduces radiation-induced fibrotic lung disease in mice without affecting the onset of distress.

  14. Neutrophils activate macrophages for intracellular killing of Leishmania major through recruitment of TLR4 by neutrophil elastase.

    Science.gov (United States)

    Ribeiro-Gomes, Flavia L; Moniz-de-Souza, Maria Carolina A; Alexandre-Moreira, Magna S; Dias, Wagner B; Lopes, Marcela F; Nunes, Marise P; Lungarella, Giuseppe; DosReis, George A

    2007-09-15

    We investigated the role of neutrophil elastase (NE) in interactions between murine inflammatory neutrophils and macrophages infected with the parasite Leishmania major. A blocker peptide specific for NE prevented the neutrophils from inducing microbicidal activity in macrophages. Inflammatory neutrophils from mutant pallid mice were defective in the spontaneous release of NE, failed to induce microbicidal activity in wild-type macrophages, and failed to reduce parasite loads upon transfer in vivo. Conversely, purified NE activated macrophages and induced microbicidal activity dependent on secretion of TNF-alpha. Induction of macrophage microbicidal activity by either neutrophils or purified NE required TLR4 expression by macrophages. Injection of purified NE shortly after infection in vivo reduced the burden of L. major in draining lymph nodes of TLR4-sufficient, but not TLR4-deficient mice. These results indicate that NE plays a previously unrecognized protective role in host responses to L. major infection.

  15. Invasive fungal infection and impaired neutrophil killing in human CARD9 deficiency.

    Science.gov (United States)

    Drewniak, Agata; Gazendam, Roel P; Tool, Anton T J; van Houdt, Michel; Jansen, Machiel H; van Hamme, John L; van Leeuwen, Ester M M; Roos, Dirk; Scalais, Emmanuel; de Beaufort, Carine; Janssen, Hans; van den Berg, Timo K; Kuijpers, Taco W

    2013-03-28

    Caspase recruitment domain-containing protein 9 (CARD9) is an adaptor molecule in the cytosol of myeloid cells, required for induction of T-helper cells producing interleukin-17 (Th17 cells) and important in antifungal immunity. In a patient suffering from Candida dubliniensis meningoencephalitis, mutations in the CARD9 gene were found to result in the loss of protein expression. Apart from the reduced numbers of CD4(+) Th17 lymphocytes, we identified a lack of monocyte-derived cytokines in response to Candida strains. Importantly, CARD9-deficient neutrophils showed a selective Candida albicans killing defect with abnormal ultrastructural phagolysosomes and outgrowth of hyphae. The neutrophil killing defect was independent of the generation of reactive oxygen species by the reduced NAD phosphate oxidase system. Taken together, this demonstrates that human CARD9 deficiency results in selective defect in the host defense against invasive fungal infection, caused by an impaired phagocyte killing.

  16. Matrix-free constructions of circulant and block circulant preconditioners

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Chao; Ng, Esmond G.; Penczek, Pawel A.

    2001-12-01

    A framework for constructing circulant and block circulant preconditioners (C) for a symmetric linear system Ax=b arising from certain signal and image processing applications is presented in this paper. The proposed scheme does not make explicit use of matrix elements of A. It is ideal for applications in which A only exists in the form of a matrix vector multiplication routine, and in which the process of extracting matrix elements of A is costly. The proposed algorithm takes advantage of the fact that for many linear systems arising from signal or image processing applications, eigenvectors of A can be well represented by a small number of Fourier modes. Therefore, the construction of C can be carried out in the frequency domain by carefully choosing its eigenvalues so that the condition number of C{sup T} AC can be reduced significantly. We illustrate how to construct the spectrum of C in a way such that the smallest eigenvalues of C{sup T} AC overlaps with those of A extremely well while the largest eigenvalues of C{sup T} AC are smaller than those of A by several orders of magnitude. Numerical examples are provided to demonstrate the effectiveness of the preconditioner on accelerating the solution of linear systems arising from image reconstruction application.

  17. A novel neutrophil derived inflammatory biomarker of pulmonary exacerbation in cystic fibrosis.

    LENUS (Irish Health Repository)

    2012-02-01

    BACKGROUND: The focus of this study was to characterize a novel biomarker for cystic fibrosis (CF) that could reflect exacerbations of the disease and could be useful for therapeutic stratification of patients, or for testing of potential drug treatments. This study focused exclusively on a protein complex containing alpha-1 antitrypsin and CD16b (AAT:CD16b) which is released into the bloodstream from membranes of pro-inflammatory primed neutrophils. METHODS: Neutrophil membrane expression and extracellular levels of AAT and CD16b were quantified by flow cytometry, Western blot analysis and by 2D-PAGE. Interleukin-8 (IL-8), tumor necrosis factor-alpha (TNF-alpha) and AAT:CD16b complex were quantified in CF plasma (n=38), samples post antibiotic treatment for 14days (n=10), chronic obstructive pulmonary disease (n=10), AAT deficient (n=10) and healthy control (n=14) plasma samples by ELISA. RESULTS: Cell priming with IL-8 and TNF-alpha caused release of the AAT:CD16b complex from the neutrophil cell membrane. Circulating plasma levels of IL-8, TNF-alpha and AAT:CD16b complex were significantly higher in patients with CF than in the other patient groups or healthy controls (P<0.05). Antibiotic treatment of pulmonary exacerbation in patients with CF led to decreased plasma protein concentrations of AAT:CD16b complex with a significant correlation with improved FEV1 (r=0.81, P=0.003). CONCLUSION: The results of this study have shown that levels of AAT:CD16b complex present in plasma correlate to the inflammatory status of patients. The AAT:CD16b biomarker may become a useful addition to the clinical diagnosis of exacerbations in CF.

  18. Regulatory T cells, dendritic cells and neutrophils in patients with renal cell carcinoma.

    Science.gov (United States)

    Minárik, Ivo; Lašťovička, Jan; Budinský, Vít; Kayserová, Jana; Spíšek, Radek; Jarolím, Ladislav; Fialová, Anna; Babjuk, Marek; Bartůňková, Jiřina

    2013-05-01

    We evaluated dendritic cells (DC), regulatory T lymphocytes (Treg) and neutrophils in 37 patients with newly diagnosed renal cell carcinoma (RCC) in the tumor and peripheral blood (PB) and correlated these parameters with tumor staging (early-T1, 2, late-T3, 4 and metastatic disease). The number of myeloid and plasmacytoid DC in blood of RCC patients was higher than in healthy controls. The percentage of myeloid dendritic cells (mDC) from CD45+ cells in tumors was higher in comparison with peripheral blood irrespective of disease stage. Higher percentage of these cells expressed a maturation marker in the periphery in the early stage (CD83 expressing cells). The number of plasmacytoid dendritic cells (pDC) in PB was similar in both early and late stage groups, but the early group displayed a significantly higher percentage of pDC in tumor cell suspension. Neutrophil counts in the peripheral blood of RCC patients were higher than in healthy controls, but the counts in both tumor stage groups were similar. The proportion of neutrophils from CD45+ cells was higher in late stage tumors. Higher percentage of Treg from CD4+ cells was detected in renal carcinoma tissue in comparison to PB with no difference between stages of the disease. Our results reflect the complex interplay between various cells of the immune system and the tumor microenvironment. Activation of dendritic cell subpopulations at early stages of the disease course is counterbalanced by the early appearance of T regulatory cells both in the periphery and tumor tissue. Later stages are characterized by the accumulation of neutrophils in the tumor. Appropriate timing of anticancer strategies, especially immunotherapy, should take these dynamics of the immune response in RCC patients into account.

  19. Dermal neutrophil, macrophage and dendritic cell responses to Yersinia pestis transmitted by fleas.

    Directory of Open Access Journals (Sweden)

    Jeffrey G Shannon

    2015-03-01

    Full Text Available Yersinia pestis, the causative agent of plague, is typically transmitted by the bite of an infected flea. Many aspects of mammalian innate immune response early after Y. pestis infection remain poorly understood. A previous study by our lab showed that neutrophils are the most prominent cell type recruited to the injection site after intradermal needle inoculation of Y. pestis, suggesting that neutrophil interactions with Y. pestis may be important in bubonic plague pathogenesis. In the present study, we developed new tools allowing for intravital microscopy of Y. pestis in the dermis of an infected mouse after transmission by its natural route of infection, the bite of an infected flea. We found that uninfected flea bites typically induced minimal neutrophil recruitment. The magnitude of neutrophil response to flea-transmitted Y. pestis varied considerably and appeared to correspond to the number of bacteria deposited at the bite site. Macrophages migrated towards flea bite sites and interacted with small numbers of flea-transmitted bacteria. Consistent with a previous study, we observed minimal interaction between Y. pestis and dendritic cells; however, dendritic cells did consistently migrate towards flea bite sites containing Y. pestis. Interestingly, we often recovered viable Y. pestis from the draining lymph node (dLN 1 h after flea feeding, indicating that the migration of bacteria from the dermis to the dLN may be more rapid than previously reported. Overall, the innate cellular host responses to flea-transmitted Y. pestis differed from and were more variable than responses to needle-inoculated bacteria. This work highlights the importance of studying the interactions between fleas, Y. pestis and the mammalian host to gain a better understanding of the early events in plague pathogenesis.

  20. Gaussian Fibonacci Circulant Type Matrices

    Directory of Open Access Journals (Sweden)

    Zhaolin Jiang

    2014-01-01

    Full Text Available Circulant matrices have become important tools in solving integrable system, Hamiltonian structure, and integral equations. In this paper, we prove that Gaussian Fibonacci circulant type matrices are invertible matrices for n>2 and give the explicit determinants and the inverse matrices. Furthermore, the upper bounds for the spread on Gaussian Fibonacci circulant and left circulant matrices are presented, respectively.

  1. Age associated variations in human neutrophil and sperm functioning

    Institute of Scientific and Technical Information of China (English)

    Kaveri Purandhar; Sriram Seshadri

    2013-01-01

    Objective: To determine the functional and biochemical variations in sperm and the neutrophil with the progression of age. Methods: Ninety healthy male subjects were selected in the age group 26-40 for the collection of semen and blood samples were collected. Basic semen analysis, hematogram, differential count serum analysis, seminal plasma and serum biochemistry was performed. Mitochondrial isolation from sperm and neutrophil was done to ascertain mitochondrial markers. Results: Our data shows a significant age-dependent reduction in the levels of mitochondrial Superoxide Dismutase (SOD) and Catalase (CAT) in sperm and the neutrophil. The functional attributes of sperm and neutrophil did not show any specific trend.Conclusion:The decreasing trend of the mitochondrial antioxidants enzymes in the sperm and the neutrophil is an indicative of the reduction in the functioning of sperm and the neutrophil. The antioxidants enzymes of sperm and neutrophil shows similar declining trend with the progression of age suggesting its possible role as a prognostic marker for age related deformities and even in male fertility.

  2. Review of the neutrophil response to Bordetella pertussis infection.

    Science.gov (United States)

    Eby, Joshua C; Hoffman, Casandra L; Gonyar, Laura A; Hewlett, Erik L

    2015-12-01

    The nature and timing of the neutrophil response to infection with Bordetella pertussis is influenced by multiple virulence factors expressed by the bacterium. After inoculation of the host airway, the recruitment of neutrophils signaled by B. pertussis lipooligosaccharide (LOS) is suppressed by pertussis toxin (PTX). Over the next week, the combined activities of PTX, LOS and adenylate cyclase toxin (ACT) result in production of cytokines that generate an IL-17 response, promoting neutrophil recruitment which peaks at 10-14 days after inoculation in mice. Arriving at the site of infection, neutrophils encounter the powerful local inhibitory activity of ACT, in conjunction with filamentous hemagglutinin. With the help of antibodies, neutrophils contribute to clearance of B. pertussis, but only after 28-35 days in a naïve mouse. Studies of the lasting, antigen-specific IL-17 response to infection in mice and baboons has led to progress in vaccine development and understanding of pathogenesis. Questions remain about the mediators that coordinate neutrophil recruitment and the mechanisms by which neutrophils overcome B. pertussis virulence factors.

  3. Ticagrelor reduces neutrophil recruitment and lung damage in abdominal sepsis.

    Science.gov (United States)

    Rahman, Milladur; Gustafsson, David; Wang, Yongzhi; Thorlacius, Henrik; Braun, Oscar Ö

    2014-01-01

    Abstract Platelets play an important role in abdominal sepsis and P2Y12 receptor antagonists have been reported to exert anti-inflammatory effects. Herein, we assessed the impact of platelet inhibition with the P2Y12 receptor antagonist ticagrelor on pulmonary neutrophil recruitment and tissue damage in a model of abdominal sepsis. Wild-type C57BL/6 mice were subjected to cecal ligation and puncture (CLP). Animals were treated with ticagrelor (100 mg/kg) or vehicle prior to CLP induction. Edema formation and bronchoalveolar neutrophils as well as lung damage were quantified. Flow cytometry was used to determine expression of platelet-neutrophil aggregates, neutrophil activation and CD40L expression on platelets. CLP-induced pulmonary infiltration of neutrophils at 24 hours was reduced by 50% in ticagrelor-treated animals. Moreover, ticagrelor abolished CLP-provoked lung edema and decreased lung damage score by 41%. Notably, ticagrelor completely inhibited formation of platelet-neutrophil aggregates and markedly reduced thrombocytopenia in CLP animals. In addition, ticagrelor reduced platelet shedding of CD40L in septic mice. Our data indicate that ticagrelor can reduce CLP-induced pulmonary neutrophil recruitment and lung damage suggesting a potential role for platelet antagonists, such as ticagrelor, in the management of patients with abdominal sepsis.

  4. Novel pathways for glucocorticoid effects on neutrophils in chronic inflammation.

    Science.gov (United States)

    Goulding, N J; Euzger, H S; Butt, S K; Perretti, M

    1998-10-01

    Neutrophils have been implicated in mediating much of the tissue damage associated with chronic inflammatory diseases such as rheumatoid arthritis, where they are involved in destruction of both cartilage and bone. Glucocorticoids are powerful anti-inflammatory agents, often used in the treatment of this autoimmune disease. They exert significant inhibitory effects on neutrophil activation and functions, such as chemotaxis, adhesion, transmigration, apoptosis, oxidative burst, and phagocytosis. The mechanisms by which glucocorticoids exert these effects on neutrophils are unclear. Evidence from studies of inflammation in human subjects and animal models suggests that annexin-I an endogenous, glucocorticoid-induced protein also known as lipocortin-1, has a pivotal role in modulating neutrophil activation, transmigratory, and phagocytic functions. Furthermore, we present evidence for altered neutrophil functions in rheumatoid arthritis that correspond to a significantly reduced capacity of these cells to bind annexin-I. A proposed novel pathway for glucocorticoid actions on neutrophils involving annexin-I could explain the development of chronic neutrophil activation in diseases such as rheumatoid arthritis.

  5. Characterization of neutrophil adhesion to different titanium surfaces

    Indian Academy of Sciences (India)

    V Campos; R C N Melo; L P Silva; E N Aquino; M S Castro; W Fontes

    2014-02-01

    Although titanium (Ti) is known to elicit a foreign body response when implanted into humans, Ti implant healing resembles normal wound healing in terms of inflammatory cell recruitment and inflammation persistence. Rough implant surfaces may present better conditions for protein adsorption and for the adhesion of platelets and inflammatory cells such as neutrophils. Implanted biomedical devices initially interact with coagulating blood; however, direct contact between the oxide layer of the implant and neutrophils has not been completely described. The aim of the present study is to compare the behaviours of neutrophils in direct contact with different Ti surfaces. Isolated human neutrophils were placed into contact with Ti discs, which had been rendered as `smooth' or `rough', following different surface treatments. Scanning electron microscopy and flow cytometry were used to measure cell adhesion to the surfaces and exposure of membrane proteins such as CD62L and CD11b. Topographic roughness was demonstrated as higher for SLA treated surfaces, measured by atomic force microscopy and elemental analysis was performed by energy dispersive X-ray, showing a similar composition for both surfaces. The adhesion of neutrophils to the `rough' Ti surface was initially stronger than adhesion to the `smooth' surface. The cell morphology and adhesion marker results revealed clear signs of neutrophil activation by either surface, with different neutrophil morphological characteristics being observed between the two surface types. Understanding the cellular mechanisms regulating cell–implant interactions should help researchers to improve the surface topography of biomedical implant devices.

  6. Alterations in Circulating Immune Cells in Neovascular Age-Related Macular Degeneration.

    Science.gov (United States)

    Lechner, Judith; Chen, Mei; Hogg, Ruth E; Toth, Levente; Silvestri, Giuliana; Chakravarthy, Usha; Xu, Heping

    2015-11-17

    Neovascular age-related macular degeneration (nAMD) is the leading cause of irreversible blindness in developed countries. Recent advances have highlighted the essential role of inflammation in the development of the disease. In addition to local retinal chronic inflammatory response, systemic immune alterations have also been observed in AMD patients. In this study we investigated the association between the frequency of circulating leukocyte populations and the prevalence as well as clinical presentations of nAMD. Leukocyte subsets of 103 nAMD patients (most of them were receiving anti-VEGF therapy prior to enrolment) and 26 controls were analysed by flow cytometry by relative cell size, granularity and surface markers. Circulating CD11b(+) cells and CD16(hi)HLA-DR(-) neutrophils were significantly increased (P = 0.015 and 0.009 respectively) in nAMD when compared to controls. The percentage of circulating CD4(+) T-cells was reduced in nAMD patients without subretinal fibrosis (P = 0.026) compared to patients with subretinal fibrosis. There was no correlation between the percentage of circulating leukocytes and the responsiveness to anti-VEGF therapy in nAMD patients. Our results suggest that higher levels of circulating CD11b(+) cells and neutrophils are associated with nAMD and that reduced levels of CD4(+) T-cells are associated with the absence of subretinal fibrosis in nAMD.

  7. Activation of AMPK enhances neutrophil chemotaxis and bacterial killing.

    Science.gov (United States)

    Park, Dae Won; Jiang, Shaoning; Tadie, Jean-Marc; Stigler, William S; Gao, Yong; Deshane, Jessy; Abraham, Edward; Zmijewski, Jaroslaw W

    2013-11-08

    An inability of neutrophils to eliminate invading microorganisms is frequently associated with severe infection and may contribute to the high mortality rates associated with sepsis. In the present studies, we examined whether metformin and other 5' adenosine monophosphate-activated protein kinase (AMPK) activators affect neutrophil motility, phagocytosis and bacterial killing. We found that activation of AMPK enhanced neutrophil chemotaxis in vitro and in vivo, and also counteracted the inhibition of chemotaxis induced by exposure of neutrophils to lipopolysaccharide (LPS). In contrast, small interfering RNA (siRNA)-mediated knockdown of AMPKα1 or blockade of AMPK activation through treatment of neutrophils with the AMPK inhibitor compound C diminished neutrophil chemotaxis. In addition to their effects on chemotaxis, treatment of neutrophils with metformin or aminoimidazole carboxamide ribonucleotide (AICAR) improved phagocytosis and bacterial killing, including more efficient eradication of bacteria in a mouse model of peritonitis-induced sepsis. Immunocytochemistry showed that, in contrast to LPS, metformin or AICAR induced robust actin polymerization and distinct formation of neutrophil leading edges. Although LPS diminished AMPK phosphorylation, metformin or AICAR was able to partially decrease the effects of LPS/toll-like receptor 4 (TLR4) engagement on downstream signaling events, particularly LPS-induced IκBα degradation. The IκB kinase (IKK) inhibitor PS-1145 diminished IκBα degradation and also prevented LPS-induced inhibition of chemotaxis. These results suggest that AMPK activation with clinically approved agents, such as metformin, may facilitate bacterial eradication in sepsis and other inflammatory conditions associated with inhibition of neutrophil activation and chemotaxis.

  8. Impaired neutrophils in children with the typical form of hemolytic uremic syndrome.

    Science.gov (United States)

    Fernández, Gabriela C; Gómez, Sonia A; Rubel, Carolina J; Bentancor, Leticia V; Barrionuevo, Paula; Alduncín, Marta; Grimoldi, Irene; Exeni, Ramón; Isturiz, Martín A; Palermo, Marina S

    2005-09-01

    Experimental and clinical evidence suggest that activated neutrophils (PMN) could contribute to endothelial damage in Hemolytic Uremic Syndrome (D+HUS). Additionally, while PMN-activating cytokines and PMN-derived products have been found in D+HUS sera, we have demonstrated phenotypic alterations in D+HUS PMN compatible with a deactivation state. Here, we investigated whether D+HUS PMN were actually hyporesponsive, and explored some of the mechanisms probably involved in their derangement. Twenty-two D+HUS children were bled in the acute period, and blood samples from healthy, acute uremic and neutrophilic children were obtained as controls. We evaluated degranulation markers in response to cytokines, intracellular granule content, and reactive oxygen species (ROS) generation in circulating D+HUS and control PMN. The influence of D+HUS-derived plasma and the direct effects of Stx in vitro were evaluated on healthy donors' PMN. We found that D+HUS PMN presented reduced degranulatory capacity in response to cytokines and intracellular granule content, and decreased ROS generation. D+HUS plasma or Stx did not affect the phenotype and function of healthy donors' PMN. These results suggest that upon hospitalization D+HUS PMN are functionally impaired and show features of previous degranulation, indicating a preceding process of activation with release of ROS and proteases involved in endothelial damage.

  9. Haem Biosynthesis and Antioxidant Enzymes in Circulating Cells of Acute Intermittent Porphyria Patients

    Science.gov (United States)

    Ferrer, Miguel D.; Mestre-Alfaro, Antonia; Martínez-Tomé, Magdalena; Carrera-Quintanar, Lucrecia; Capó, Xavier; Jiménez-Monreal, Antonia M.; García-Diz, Luis; Roche, Enrique; Murcia, María A.; Tur, Josep A.

    2016-01-01

    The aims of the present study were to explore the expression pattern of haem biosynthesis enzymes in circulating cells of patients affected by two types of porphyria (acute intermittent, AIP, and variegate porphyria, VP), together with the antioxidant enzyme pattern in AIP in order to identify a possible situation of oxidative stress. Sixteen and twelve patients affected by AIP and VP, respectively, were analysed with the same numbers of healthy matched controls. Erythrocytes, neutrophils and peripheral blood mononuclear cells (PBMCs) were purified from blood, and RNA and proteins were extracted for quantitative real time PCR (qRT-PCR) and Western-blot analysis, respectively. Porhobilinogen deaminase (PBGD) and protoporphyrinogen oxidase (PPOX) gene and protein expression was analysed. Antioxidant enzyme activity and gene expression were additionally determined in blood cells, together with protein carbonyl content in plasma. PBMCs isolated from AIP patients presented low mRNA levels of PBGD when compared to controls, while PBMCs isolated from VP patients presented a decrease in PPOX mRNA. PPOX protein content was higher in AIP patients and lower in VP patients, compared to healthy controls. Regarding antioxidant enzymes, PBMCs and erythrocyte superoxide dismutase (SOD) presented statistically significant higher activity in AIP patients compared to controls, while catalase activity tended to be lower in these patients. No differences were observed regarding antioxidant gene expression in white blood cells. Circulating cells in AIP and VP patients present altered expression of haem biosynthetic enzymes, which could be useful for the differential diagnosis of these two types of porphyria in certain difficult cases. AIP patients present a condition of potential oxidative stress similar to VP patients, evidenced by the post-transcriptional activation of SOD and possible catalase impairment. PMID:27788171

  10. Circulant Double Coverings of a Circulant Graph of Valency Five

    Institute of Scientific and Technical Information of China (English)

    Rong Quan FENG; Jin Ho KWAK

    2007-01-01

    Enumerating the isomorphism classes of several types of graph covering projections is one of the central research topics in enumerative topological graph theory. A covering of G is called circulant if its covering graph is circulant. Recently, the authors [Discrete Math., 277, 73-85 (2004)]enumerated the isomorphism classes of circulant double coverings of a certain type, called a typicalcovering, and showed that no double covering of a circulant graph of valency three is circulant. Also, in [Graphs and Combinatorics, 21, 386-400 (2005)], the isomorphism classes of circulant double coverings of a circulant graph of valency four are enumerated. In this paper, the isomorphism classes of circulant double coverings of a circulant graph of valency five are enumerated.

  11. Kernels in circulant digraphs

    Directory of Open Access Journals (Sweden)

    R. Lakshmi

    2014-06-01

    Full Text Available A kernel $J$ of a digraph $D$ is an independent set of vertices of $D$ such that for every vertex $w,in,V(D,setminus,J$ there exists an arc from $w$ to a vertex in $J.$ In this paper, among other results, a characterization of $2$-regular circulant digraph having a kernel is obtained. This characterization is a partial solution to the following problem: Characterize circulant digraphs which have kernels; it appeared in the book {it Digraphs - theory, algorithms and applications}, Second Edition, Springer-Verlag, 2009, by J. Bang-Jensen and G. Gutin.

  12. Depletion of Neutrophils Promotes the Resolution of Pulmonary Inflammation and Fibrosis in Mice Infected with Paracoccidioides brasiliensis

    Science.gov (United States)

    Arango, Julián Camilo

    2016-01-01

    Chronic stages of paracoccidioidomycosis (PCM) are characterized by granulomatous lesions which promote the development of pulmonary fibrosis leading to the loss of respiratory function in 50% of patients; in addition, it has been observed that neutrophils predominate during these chronic stages of P. brasiliensis infection. The goal of this study was to evaluate the role of the neutrophil during the chronic stages of experimental pulmonary PCM and during the fibrosis development and tissue repair using a monoclonal specific to this phagocytic cell. Male BALB/c mice were inoculated intranasally with 1.5x106 P. brasiliensis yeast cells. A monoclonal antibody specific to neutrophils was administered at 4 weeks post-inoculation followed by doses every 48h during two weeks. Mice were sacrificed at 8 and 12 weeks post-inoculation to assess cellularity, fungal load, cytokine/chemokine levels, histopathological analysis, collagen and expression of genes related to fibrosis development. Depletion of neutrophils was associated with a significant decrease in the number of eosinophils, dendritic cells, B cells, CD4-T cells, MDSCs and Treg cells, fungal load and levels of most of the pro-inflammatory cytokines/chemokines evaluated, including IL-17, TNF-α and TGF-β1. Recovery of lung architecture was also associated with reduced levels of collagen, high expression of TGF-β3, matrix metalloproteinase (MMP)-12 and -14, and decreased expression of tissue inhibitor metalloproteinase (TIMP)-2, and MMP-8. Depletion of neutrophils might attenuate lung fibrosis and inflammation through down-regulating TGF-β1, TNF-α, IL-17, MMP-8 and TIMP-2. These results suggest that neutrophil could be considered as a therapeutic target in pulmonary fibrosis induced by P. brasiliensis. PMID:27690127

  13. L-Carnitine Supplementation Reduces Short-Term Neutrophil-Lymphocyte Ratio in Patients Undergoing Coronary Artery Bypass Grafting.

    Science.gov (United States)

    Aldemir, Mustafa; Pektaş, Mehmet Bilgehan; Parlar, Ali İhsan; Akcı, Önder; Emren, Sadık Volkan; Tecer, Evren; Adalı, Fahri; Yüksel, Şeref; Darçın, Osman Tansel

    2015-07-01

    This study aims to investigate whether preoperative L-carnitine supplementation affects the neutrophil-to-lymphocyte ratio (NLR) in patients undergoing coronary artery bypass grafting surgery. The neutrophil-to-lymphocyte ratio is an inflammatory marker that has proven usefulness for predicting postoperative complications in coronary artery bypass surgery. A lot of studies concerning the role of L-carnitine in the immune system have been performed, contradictory results have been reported on its effects on absolute numbers of WBC subtypes. This randomized, double-blinded, placebo-controlled study was conducted among patients scheduled for coronary artery bypass grafting surgery between June 2012 and December 2013 in our cardiovascular surgery clinic. A total of 60 consecutive patients were randomized and divided into 2 groups. The first group received 2 g of L-carnitine in 1000 mL of 0.9% saline solution infused over 24 hours for each of the 3 preoperative days (L-carnitine group, n = 30), or only 1000 mL of 0.9% saline solution for the same time period (placebo group, n = 30). The basal values of leukocyte, neutrophil, lymphocyte counts, and neutrophil to lymphocyte ratio were similar in the 2 groups. After L-carnitine supplementation (just before surgery), leukocyte and neutrophil counts of the L-carnitine group were significantly lower than those of the placebo group (7.7 ± 1.5 versus 9.7 ± 2.6, P carnitine group (1.1 ± 0.6 versus 0.8 ± 0.9, P carnitine group at postoperative day 1 (20.7 ± 13.8 versus 10.8 ± 4.1, P carnitine supplementation may reduce neutrophil-lymphocyte ratio during the early postoperative period of coronary artery bypass grafting surgery.

  14. 3,4-methylenedioxymethamphetamine (MDMA--Ecstasy) decreases neutrophil activity through the glucocorticoid pathway and impairs host resistance to Listeria monocytogenes infection in mice.

    Science.gov (United States)

    Ferraz-de-Paula, V; Ribeiro, A; Souza-Queiroz, J; Pinheiro, M L; Vecina, J F; Souza, D P M; Quinteiro-Filho, W M; Moreau, R L M; Queiroz, M L S; Palermo-Neto, J

    2014-12-01

    Ecstasy is the popular name of the abuse drug 3,4-methylenedioxymethamphetamine (MDMA) that decreases immunity in animals. The mechanisms that generate such alterations are still controversial. Seven independent pharmacological approaches were performed in mice to identify the possible mechanisms underlying the decrease of neutrophil activity induced by MDMA and the possible effects of MDMA on host resistance to Listeria monocytogenes. Our data showed that MDMA (10 mg kg(-1)) administration decreases NFκB expression in circulating neutrophils. Metyrapone or RU-486 administration prior to MDMA treatment abrogated MDMA effects on neutrophil activity and NFκB expression, while 6-OHDA or ICI-118,551 administration did not. As MDMA treatment increased the plasmatic levels of adrenaline and noradrenaline, propranolol pre-treatment effects were also evaluated. Propranolol suppressed both MDMA-induced increase in corticosterone serum levels and its effects on neutrophil activity. In a L. monocytogenes experimental infection context, we showed that MDMA: induced myelosuppression by decreasing granulocyte-macrophage hematopoietic progenitors (CFU-GM) in the bone marrow but increased CFU-GM in the spleen; decreased circulating leukocytes and bone marrow cellularity and increased spleen cellularity; decreased pro-inflammatory cytokine (IL-12p70, TNF, IFN-γ, IL-6) and chemokine (MCP-1) production 24 h after the infection; increased the production of pro-inflammatory cytokines and chemokines 72 h after infection and decreased IL-10 levels at all time points analyzed. It was proposed that MDMA immunosuppressive effects on neutrophil activity and host resistance to L monocytogenes rely on NFκB signaling, being mediated by HPA axis activity and corticosterone.

  15. PhagoSight: an open-source MATLAB® package for the analysis of fluorescent neutrophil and macrophage migration in a zebrafish model.

    Directory of Open Access Journals (Sweden)

    Katherine M Henry

    Full Text Available Neutrophil migration in zebrafish larvae is increasingly used as a model to study the response of these leukocytes to different determinants of the cellular inflammatory response. However, it remains challenging to extract comprehensive information describing the behaviour of neutrophils from the multi-dimensional data sets acquired with widefield or confocal microscopes. Here, we describe PhagoSight, an open-source software package for the segmentation, tracking and visualisation of migrating phagocytes in three dimensions. The algorithms in PhagoSight extract a large number of measurements that summarise the behaviour of neutrophils, but that could potentially be applied to any moving fluorescent cells. To derive a useful panel of variables quantifying aspects of neutrophil migratory behaviour, and to demonstrate the utility of PhagoSight, we evaluated changes in the volume of migrating neutrophils. Cell volume increased as neutrophils migrated towards the wound region of injured zebrafish. PhagoSight is openly available as MATLAB® m-files under the GNU General Public License. Synthetic data sets and a comprehensive user manual are available from http://www.phagosight.org.

  16. Neutropenic Mice Provide Insight into the Role of Skin-Infiltrating Neutrophils in the Host Protective Immunity against Filarial Infective Larvae

    Science.gov (United States)

    Pionnier, Nicolas; Brotin, Emilie; Karadjian, Gregory; Hemon, Patrice; Gaudin-Nomé, Françoise; Vallarino-Lhermitte, Nathaly; Nieguitsila, Adélaïde; Fercoq, Frédéric; Aknin, Marie-Laure; Marin-Esteban, Viviana; Chollet-Martin, Sylvie; Schlecht-Louf, Géraldine

    2016-01-01

    Our knowledge and control of the pathogenesis induced by the filariae remain limited due to experimental obstacles presented by parasitic nematode biology and the lack of selective prophylactic or curative drugs. Here we thought to investigate the role of neutrophils in the host innate immune response to the infection caused by the Litomosoides sigmodontis murine model of human filariasis using mice harboring a gain-of-function mutation of the chemokine receptor CXCR4 and characterized by a profound blood neutropenia (Cxcr4+/1013). We provided manifold evidence emphasizing the major role of neutrophils in the control of the early stages of infection occurring in the skin. Firstly, we uncovered that the filarial parasitic success was dramatically decreased in Cxcr4+/1013 mice upon subcutaneous delivery of the infective stages of filariae (infective larvae, L3). This protection was linked to a larger number of neutrophils constitutively present in the skin of the mutant mice herein characterized as compared to wild type (wt) mice. Indeed, the parasitic success in Cxcr4+/1013 mice was normalized either upon depleting neutrophils, including the pool in the skin, or bypassing the skin via the intravenous infection of L3. Second, extending these observations to wt mice we found that subcutaneous delivery of L3 elicited an increase of neutrophils in the skin. Finally, living L3 larvae were able to promote in both wt and mutant mice, an oxidative burst response and the release of neutrophil extracellular traps (NET). This response of neutrophils, which is adapted to the large size of the L3 infective stages, likely directly contributes to the anti-parasitic strategies implemented by the host. Collectively, our results are demonstrating the contribution of neutrophils in early anti-filarial host responses through their capacity to undertake different anti-filarial strategies such as oxidative burst, degranulation and NETosis. PMID:27111140

  17. Resuscitation of traumatic hemorrhagic shock patients with hypertonic saline-without dextran-inhibits neutrophil and endothelial cell activation.

    Science.gov (United States)

    Junger, Wolfgang G; Rhind, Shawn G; Rizoli, Sandro B; Cuschieri, Joseph; Shiu, Maria Y; Baker, Andrew J; Li, Linglin; Shek, Pang N; Hoyt, David B; Bulger, Eileen M

    2012-10-01

    Posttraumatic inflammation and excessive neutrophil activation cause multiple organ dysfunction syndrome (MODS), a major cause of death among hemorrhagic shock patients. Traditional resuscitation strategies may exacerbate inflammation; thus, novel fluid treatments are needed to reduce such posttraumatic complications. Hypertonic resuscitation fluids inhibit inflammation and reduce MODS in animal models. Here we studied the anti-inflammatory efficacy of hypertonic fluids in a controlled clinical trial. Trauma patients in hypovolemic shock were resuscitated in a prehospital setting with 250 mL of either 7.5% hypertonic saline (HS; n = 9), 7.5% hypertonic saline + 6% dextran 70 (HSD; n = 8), or 0.9% normal saline (NS; n = 17). Blood samples were collected on hospital admission and 12 and 24 h after resuscitation. Multicolor flow cytometry was used to quantify neutrophil expression of cell-surface activation/adhesion (CD11b, CD62L, CD64) and degranulation (CD63, CD66b, CD35) markers as well as oxidative burst activity. Circulating concentrations of soluble intercellular adhesion molecule-1 (sICAM-1), vascular cell adhesion molecule-1 (sVACM-1), P- and E-selectins, myeloperoxidase (MPO), and matrix metalloproteinase 9 (MMP-9) were assessed by immunoassay. Multiple organ dysfunction syndrome, leukocytosis, and mortality were lower in the HS and HSD groups than in the NS group. However, these differences were not statistically significant. Hypertonic saline prevented priming and activation and neutrophil oxidative burst and CD11b and CD66b expression. Hypertonic saline also reduced circulating markers of neutrophil degranulation (MPO and MMP-9) and endothelial cell activation (sICAM-1, sVCAM-1, soluble E-selectin, and soluble P-selectin). Hypertonic saline + 6% dextran 70 was less capable than HS of suppressing the upregulation of most of these activation markers. This study demonstrates that initial resuscitation with HS, but neither NS nor HSD, can attenuate

  18. CellTracks cytometer for detection of circulating tumor cells

    NARCIS (Netherlands)

    Tibbe, A.G.J.; Kooi, van der A.; Groot, de M.R.; Vermes, I.

    2003-01-01

    Introduction: In patients with carcinomas, tumor cells are shed into the circulation. The number of the circulating tumor cells is low and technology is needed that has sufficient sensitivity and specificity to enumerate and characterize these cells. The CellTracks system was developed to provide an

  19. Hypoxia Selectively Inhibits Respiratory Burst Activity and Killing of Staphylococcus aureus in Human Neutrophils

    OpenAIRE

    McGovern, Naomi N.; Cowburn, Andrew S.; Porter, Linsey; Walmsley, Sarah R.; Summers, Charlotte; Thompson, Alfred A. R.; Anwar, Sadia; Willcocks, Lisa C.; Moira K B Whyte; Condliffe, Alison M; Chilvers, Edwin R.

    2010-01-01

    Neutrophils play a central role in the innate immune response and a critical role in bacterial killing. Most studies of neutrophil function have been conducted under conditions of ambient oxygen, but inflamed sites where neutrophils operate may be extremely hypoxic. Previous studies indicate that neutrophils sense and respond to hypoxia via the ubiquitous prolyl hydroxylase/hypoxia-inducible factor pathway and that this can signal for enhanced survival. In the current study, human neutrophils...

  20. Oxidative burst of neutrophils against melanoma B16-F10.

    Science.gov (United States)

    Zivkovic, Morana; Poljak-Blazi, Marija; Zarkovic, Kamelija; Mihaljevic, Danijela; Schaur, Rudolf Joerg; Zarkovic, Neven

    2007-02-08

    Intensive oxidative burst was determined by chemiluminescence of peripheral blood neutrophils of mice that were intramuscularly injected with melanoma B16-F10 and/or subcutaneously with Sephadex G-200. The neutrophils from papula developed at the site of Sephadex injection were cytotoxic for the B16-F10 cells in vitro. However, survival of Sephadex injected tumour-bearing mice was lower than of control animals bearing B16-F10, while their tumours grew faster and were less necrotic. Thus, it is likely that injection of Sephadex distracted the neutrophils from the tumour allowing faster progression of the tumour, indicating that neutrophils may have an important role in the host defence against malignant cells in the early stage of tumour development.

  1. [The phagocytosis of polymorphonuclear neutrophilic granulocytes in progressive periodontitis].

    Science.gov (United States)

    Konopka, T; Zietek, M

    1995-01-01

    The aim of this paper was the evaluation of the phagocytic activity of neutrophils in blood and in gingival pocket fluid in patients suffering from rapidly progressive periodontitis (RPP) and postjuvenile periodontitis (PJP). Prior to periodontal treatment the authors evaluated the capacity to phagocytose latex particles of peripheral blood neutrophils from 21 patients with RPP, 51 with PJP and 59 healthy subjects (control group) as well as the phagocytic activity of neutrophils in pocket fluid from 21 patients with RPP, 14 with PJP and from 20 healthy subjects. This phagocytic activity was significantly lower in all examined groups in comparison with the control group. A similar evaluation executed 3 months after treatment revealed normal phagocytosis of blood neutrophils from patients with RPP. In patients receiving complementary pharmacotherapy (spiramycine combined with metronidazol), a better improvement of phagocytosis was noted, than that observed in patients treated only surgically.

  2. Neutrophils and intracellular pathogens: beyond phagocytosis and killing.

    Science.gov (United States)

    Appelberg, Rui

    2007-02-01

    Neutrophils are not simply scavenging phagocytes that clear extracellular spaces of rapidly proliferating microbes; they are also active in the control of infections by intracellular pathogens. Several mechanisms for nonphagocytic roles of neutrophils in protective immunity have been put forth over the years but further evidence has recently been accumulating at an increasing pace. In this review, I present the evidence that suggests neutrophils are involved in pathogen shuttling into the lymphoid tissues, in antigen presentation, and in early T cell recruitment and initiation of granuloma organization. Also, a clearer view on the antimicrobial molecules that can be acquired by macrophages to enhance their antimicrobial activity is now emerging. Finally, neutrophils can adversely affect immunity against certain parasites by causing immune deviation.

  3. Neutrophil microbial killing mechanisms: Lessons learned from primary immunodeficiencies

    NARCIS (Netherlands)

    Gazendam, R.P.

    2016-01-01

    Humans and microbes have a balanced and longstanding relationship. Immunosuppresive therapies and primary immunodeficiencies (PIDs) may disturb this balance and result in infection. Patients with neutropenia or PIDs with neutrophil functional defects, including Chronic Granulomatous Disease (CGD), a

  4. Activation of the neutrophil NADPH oxidase by Aspergillus fumigatus.

    Science.gov (United States)

    Boyle, Keith B; Stephens, Len R; Hawkins, Phillip T

    2012-12-01

    Upon infection of the respiratory system with the fungus Aspergillus fumigatus various leukoctytes, in particular neutrophils, are recruited to the lung to mount an immune response. Neutrophils respond by both phagocytosing conidia and mediating extracellular killing of germinated, invasive hyphae. Of paramount importance to an appropriate immune response is the neutrophil NADPH oxidase enzyme, which mediates the production of various reactive oxygen species (ROS). This is evidenced by the acute sensitivity of both oxidase-deficient humans and mice to invasive aspergillosis. Herein we briefly review the mechanisms and functions of oxidase activation and discuss our recent work identifying at least some of the important players in hyphal-induced oxidase activation and neutrophil function. Among these we define the phosphoinositide 3-kinase enzyme and the regulatory protein Vav to be of critical importance and allude to a kinase-independent role for Syk.

  5. Neutrophil extracellular traps in dermatology: Caught in the NET.

    Science.gov (United States)

    Hoffmann, Jochen H O; Enk, Alexander H

    2016-10-01

    Neutrophil, or polymorphonuclear granulocytes (PMN) constitute the most abundant type of leucocytes in peripheral human blood. One of the major advances in the last decade was the discovery of neutrophil extracellular trap (NET) formation: a process by which neutrophils externalize web-like chromatin strands decorated with antimicrobial peptides. These structures were soon implicated in immune defense and auto-immunity alike and now link neutrophils to the pathogenesis of a variety of diseases of dermatological relevance. Currently, NET formation is mainly subdivided into suicidal and vital NETosis. Controversy exists regarding the capacity of NETs to kill pathogens, and little is known about the way NETs are formed in vivo. Here, we discuss the current terminology, methods for NET quantification, pathways leading to NET formation, and the role of NETs in systemic and cutaneous immune defense and auto-immunity, with a focus on psoriasis and systemic lupus erythematosus.

  6. Cryptococcal capsular glucuronoxylomannan reduces ischaemia-related neutrophil influx

    NARCIS (Netherlands)

    Ellerbroek, PM; Schoemaker, RG; van Veghel, R; Hoepelman, AIM; Coenjaerts, FEJ

    2004-01-01

    Background The capsular polysaccharide glucuronoxylomannan (GXM) of Cryptococcus neoformans interferes with the chemotaxis and transendothelial migration of neutrophils. Intravenous administration of purified GXM has been shown to reduce the influx of inflammatory cells in an animal model of bacteri

  7. Mechanism of neutrophil recruitment to the lung after pulmonary contusion

    OpenAIRE

    2011-01-01

    Blunt chest trauma resulting in pulmonary contusion is a common but poorly understood injury. We previously demonstrated that lung contusion activates localized and systemic innate immune mechanisms and recruits neutrophils to the injured lung. We hypothesized that the innate immune and inflammatory activation of neutrophils may figure prominently in the response to lung injury. To investigate this, we used a model of pulmonary contusion in the mouse that is similar to that observed clinicall...

  8. Neutrophils cast extracellular traps in response to protozoan parasites.

    Science.gov (United States)

    Abi Abdallah, Delbert S; Denkers, Eric Y

    2012-01-01

    Release of extracellular traps by neutrophils is a now well-established phenomenon that contributes to the innate response to extracellular bacterial and fungal pathogens. The importance of NETs during protozoan infection has been less explored, but recent findings suggest an emerging role for release of neutrophil-derived extracellular DNA in response to this class of microbial pathogens. The present review summarizes findings to date regarding elicitation of NETs by Toxoplasma gondii, Plasmodium falciparum, Eimeria bovis, and Leishmania spp.

  9. Salivary duct carcinoma with striking neutrophil-tumor cell cannibalism

    OpenAIRE

    Payam Arya; Khalbuss, Walid E.; Monaco, Sara E.; Liron Pantanowitz

    2011-01-01

    Cannibalism of neutrophils by tumor cells has previously been reported in certain carcinomas, lymphoma and melanoma. Tumor cannibalism is believed to serve as a tumor-immune escape mechanism, associated with high-grade aggressive cancers with a significantly increased metastatic potential. This interesting phenomenon has not been previously documented in association with salivary gland tumors. We report, for the first time, striking neutrophil-tumor cell cannibalism associated with a high gra...

  10. Neutrophil function and metabolism in individuals with diabetes mellitus

    Directory of Open Access Journals (Sweden)

    T.C. Alba-Loureiro

    2007-08-01

    Full Text Available Neutrophils act as first-line-of-defense cells and the reduction of their functional activity contributes to the high susceptibilityto and severity of infections in diabetes mellitus. Clinical investigations in diabetic patients and experimental studies in diabetic rats and mice clearly demonstrated consistent defects of neutrophil chemotactic, phagocytic and microbicidal activities. Other alterations that have been reported to occur during inflammation in diabetes mellitus include: decreased microvascular responses to inflammatory mediators such as histamine and bradykinin, reduced protein leakage and edema formation, reduced mast cell degranulation, impairment of neutrophil adhesionto the endothelium and migration to the site of inflammation, production of reactive oxygen species and reduced release of cytokines and prostaglandin by neutrophils, increased leukocyte apoptosis, and reduction in lymph node retention capacity. Since neutrophil function requires energy, metabolic changes (i.e., glycolytic and glutaminolytic pathways may be involved in the reduction of neutrophil function observed in diabetic states. Metabolic routes by which hyperglycemia is linked to neutrophil dysfunction include the advanced protein glycosylation reaction, the polyol pathway, oxygen-free radical formation, the nitric oxide-cyclic guanosine-3'-5'monophosphate pathway, and the glycolytic and glutaminolytic pathways. Lowering of blood glucose levels by insulin treatment of diabetic patients or experimental animals has been reported to have significant correlation with improvement of neutrophil functional activity. Therefore, changes might be primarily linked to a continuing insulin deficiency or to secondary hyperglycemia occurring in the diabetic individual. Accordingly, effective control with insulin treatment is likely to be relevant during infection in diabetic patients.

  11. Polyphenol derivatives – potential regulators of neutrophil activity

    OpenAIRE

    2012-01-01

    The study provides new information on the effect of natural polyphenols (derivatives of stilbene – resveratrol, pterostilbene, pinosylvin and piceatannol and derivatives of ferulic acid – curcumin, N-feruloylserotonin) on the activity of human neutrophils in influencing oxidative burst. All the polyphenols tested were found to reduce markedly the production of reactive oxygen species released by human neutrophils on extra-and intracellular levels as well as in cell free system. Moreover, pino...

  12. Hypertrophic pachymeningitis: significance of myeloperoxidase anti-neutrophil cytoplasmic antibody.

    Science.gov (United States)

    Yokoseki, Akiko; Saji, Etsuji; Arakawa, Musashi; Kosaka, Takayuki; Hokari, Mariko; Toyoshima, Yasuko; Okamoto, Kouichirou; Takeda, Shigeki; Sanpei, Kazuhiro; Kikuchi, Hirotoshi; Hirohata, Shunsei; Akazawa, Kouhei; Kakita, Akiyoshi; Takahashi, Hitoshi; Nishizawa, Masatoyo; Kawachi, Izumi

    2014-02-01

    The aim of this study was to elucidate the characteristics, pathogenesis and treatment strategy of hypertrophic pachymeningitis that is associated with myeloperoxidase anti-neutrophil cytoplasmic antibody (ANCA). We retrospectively investigated clinical, radiological, immunological and pathological profiles of 36 patients with immune-mediated or idiopathic hypertrophic pachymeningitis, including 17 patients with myeloperoxidase-ANCA, four patients with proteinase 3-ANCA, six patients with other immune-mediated disorders, and nine patients with 'idiopathic' variety. Myeloperoxidase-ANCA-positive hypertrophic pachymeningitis was characterized by: (i) an elderly female predominance; (ii) 82% of patients diagnosed with granulomatosis with polyangiitis (previously known as Wegener's granulomatosis) according to Watts' algorithm; (iii) a high frequency of patients with lesions limited to the dura mater and upper airways, developing headaches, chronic sinusitis, otitis media or mastoiditis; (iv) a low frequency of patients with the 'classical or generalized form' of granulomatosis with polyangiitis involving the entire upper and lower airways and kidney, or progressing to generalized disease, in contrast to proteinase 3-ANCA-positive hypertrophic pachymeningitis; (v) less severe neurological damage according to the modified Rankin Scale and low disease activity according to the Birmingham Vasculitis Activity Score compared with proteinase 3-ANCA-positive hypertrophic pachymeningitis; (vi) increased levels of CXCL10, CXCL8 and interleukin 6 in cerebrospinal fluids, and increased numbers of T cells, neutrophils, eosinophils, plasma cells and monocytes/macrophages in autopsied or biopsied dura mater with pachymeningitis, suggesting TH1-predominant granulomatous lesions in hypertrophic pachymeningitis, as previously reported in pulmonary or renal lesions of granulomatosis with polyangiitis; and (vii) greater efficacy of combination therapy with prednisolone and

  13. Increased expression of the chemokines CXCL1 and MIP-1α by resident brain cells precedes neutrophil infiltration in the brain following prolonged soman-induced status epilepticus in rats

    Directory of Open Access Journals (Sweden)

    Koemeter-Cox Andrew I

    2011-05-01

    Full Text Available Abstract Background Exposure to the nerve agent soman (GD causes neuronal cell death and impaired behavioral function dependent on the induction of status epilepticus (SE. Little is known about the maturation of this pathological process, though neuroinflammation and infiltration of neutrophils are prominent features. The purpose of this study is to quantify the regional and temporal progression of early chemotactic signals, describe the cellular expression of these factors and the relationship between expression and neutrophil infiltration in damaged brain using a rat GD seizure model. Methods Protein levels of 4 chemokines responsible for neutrophil infiltration and activation were quantified up to 72 hours in multiple brain regions (i.e. piriform cortex, hippocampus and thalamus following SE onset using multiplex bead immunoassays. Chemokines with significantly increased protein levels were localized to resident brain cells (i.e. neurons, astrocytes, microglia and endothelial cells. Lastly, neutrophil infiltration into these brain regions was quantified and correlated to the expression of these chemokines. Results We observed significant concentration increases for CXCL1 and MIP-1α after seizure onset. CXCL1 expression originated from neurons and endothelial cells while MIP-1α was expressed by neurons and microglia. Lastly, the expression of these chemokines directly preceded and positively correlated with significant neutrophil infiltration in the brain. These data suggest that following GD-induced SE, a strong chemotactic response originating from various brain cells, recruits circulating neutrophils to the injured brain. Conclusions A strong induction of neutrophil attractant chemokines occurs following GD-induced SE resulting in neutrophil influx into injured brain tissues. This process may play a key role in the progressive secondary brain pathology observed in this model though further study is warranted.

  14. Mechanics of neutrophil phagocytosis: experiments and quantitative models.

    Science.gov (United States)

    Herant, Marc; Heinrich, Volkmar; Dembo, Micah

    2006-05-01

    To quantitatively characterize the mechanical processes that drive phagocytosis, we observed the FcgammaR-driven engulfment of antibody-coated beads of diameters 3 mum to 11 mum by initially spherical neutrophils. In particular, the time course of cell morphology, of bead motion and of cortical tension were determined. Here, we introduce a number of mechanistic models for phagocytosis and test their validity by comparing the experimental data with finite element computations for multiple bead sizes. We find that the optimal models involve two key mechanical interactions: a repulsion or pressure between cytoskeleton and free membrane that drives protrusion, and an attraction between cytoskeleton and membrane newly adherent to the bead that flattens the cell into a thin lamella. Other models such as cytoskeletal expansion or swelling appear to be ruled out as main drivers of phagocytosis because of the characteristics of bead motion during engulfment. We finally show that the protrusive force necessary for the engulfment of large beads points towards storage of strain energy in the cytoskeleton over a large distance from the leading edge ( approximately 0.5 microm), and that the flattening force can plausibly be generated by the known concentrations of unconventional myosins at the leading edge.

  15. Inhibition of neutrophil-mediated production of reactive oxygen species (ROS) by endothelial cells is not impaired in anti-neutrophil cytoplasmic autoantibodies (ANCA)-associated vasculitis patients

    NARCIS (Netherlands)

    Al Laham, F.; Kaelsch, A. -I.; Heinrich, L.; Birck, R.; Kallenberg, C. G. M.; Heeringa, P.; Yard, B.

    2010-01-01

    P>Leucocyte transendothelial migration is strictly regulated to prevent undesired inflammation and collateral damage of endothelial cells by activated neutrophils/monocytes. We hypothesized that in anti-neutrophil cytoplasmic autoantibodies (ANCA)-associated vasculitis (AAV) patients' dysregulation

  16. Simultaneous mobilization of Mac-1 (CD11b/CD18) and formyl peptide chemoattractant receptors in human neutrophils.

    Science.gov (United States)

    Graves, V; Gabig, T; McCarthy, L; Strour, E F; Leemhuis, T; English, D

    1992-08-01

    Mobilization of a distinct subset of specific granules provides a physiologically important mechanism to recruit Mac-1 (CD11b/CD18) from an intracellular pool to the external surface of the neutrophil plasma membrane, where the functionally active heterodimer mediates several adherence-dependent processes that are crucial for adequate host defense and cellular inflammatory responses. We observed similar characteristics for translocation of Mac-1 and neutrophil formyl peptide receptors (FPR) and hypothesize that the readily accessible pools of both Mac-1 and FPR are colocalized within this specific granule subset. Plasma membrane levels of both FPR (assessed with 3H-FMLP) and Mac-1 (assessed by fluorescence-activated cell sorter analysis of fluorescein isothiocyanate [FITC]-Mo-1-labeled cells) were markedly downregulated in cells prepared at low temperature from blood cooled to 4 degrees C immediately after removal from the circulation. Levels of both FPR and Mac-1 remained low on cells held at 4 degrees C. Upon warming, spontaneous upregulation of Mac-1 and FPR occurred with similar kinetics and temperature dependency. Translocation of both Mac-1 and FPR was markedly potentiated by exposure of cells to either fluoride ion (which has been shown by others to specifically elicit exocytosis of gelatinase-rich and vitamin B-12 binding protein-poor granules) or granulocyte-macrophage colony-stimulating factor (GM-CSF), a cytokine that markedly potentiates the neutrophils' host defense capabilities. Levels of both FPR and Mac-1 on F-- or GM-CSF-treated neutrophils exceeded those present on cells incubated at 37 degrees C for extended time intervals, indicating that stimulated translocation may involve mobilization of an additional granule subset. Scatchard analysis showed that only low-affinity FPR were translocated during spontaneous and stimulus-dependent upregulation. To directly compare FPR levels on the surface of cells displaying varying levels of Mac-1 within a

  17. Suppressed neutrophil function in children with acute lymphoblastic leukemia.

    Science.gov (United States)

    Tanaka, Fumiko; Goto, Hiroaki; Yokosuka, Tomoko; Yanagimachi, Masakatsu; Kajiwara, Ryosuke; Naruto, Takuya; Nishimaki, Shigeru; Yokota, Shumpei

    2009-10-01

    Infection is a major obstacle in cancer chemotherapy. Neutropenia has been considered to be the most important risk factor for severe infection; however, other factors, such as impaired neutrophil function, may be involved in susceptibility to infection in patients undergoing chemotherapy. In this study, we analyzed neutrophil function in children with acute lymphoblastic leukemia (ALL). Whole blood samples were obtained from 16 children with ALL at diagnosis, after induction chemotherapy, and after consolidation chemotherapy. Oxidative burst and phagocytic activity of neutrophils were analyzed by flow cytometry. Oxidative burst of neutrophils was impaired in ALL patients. The percentage of neutrophils with normal oxidative burst after PMA stimulation was 59.0 +/- 13.2 or 70.0 +/- 21.0% at diagnosis or after induction chemotherapy, respectively, which was significantly lower compared with 93.8 +/- 6.1% in healthy control subjects (P = 0.00004, or 0.002, respectively); however, this value was normal after consolidation chemotherapy. No significant differences were noted in phagocytic activity in children with ALL compared with healthy control subjects. Impaired oxidative burst of neutrophils may be one risk factor for infections in children with ALL, especially in the initial periods of treatment.

  18. Tumor-Associated Macrophages and Neutrophils in Tumor Microenvironment

    Directory of Open Access Journals (Sweden)

    Jaehong Kim

    2016-01-01

    Full Text Available Distinct tumor microenvironment forms in each progression step of cancer and has diverse capacities to induce both adverse and beneficial consequences for tumorigenesis. It is now known that immune cells can be activated to favor tumor growth and progression, most probably influenced by the tumor microenvironment. Tumor-associated macrophages and tumor-associated neutrophils can exert protumoral functions, enhancing tumor cell invasion and metastasis, angiogenesis, and extracellular matrix remodeling, while inhibiting the antitumoral immune surveillance. Considering that neutrophils in inflammatory environments recruit macrophages and that recruited macrophages affect neutrophil functions, there may be various degrees of interaction between tumor-associated macrophages and tumor-associated neutrophils. Platelets also play an important role in the recruitment and regulation of monocytic and granulocytic cells in the tumor tissues, suggesting that platelet function may be essential for generation of tumor-associated macrophages and tumor-associated neutrophils. In this review, we will explore the biology of tumor-associated macrophages and tumor-associated neutrophils and their possible interactions in the tumor microenvironment. Special attention will be given to the recruitment and activation of these tumor-associated cells and to the roles they play in maintenance of the tumor microenvironment and progression of tumors.

  19. Free p-Cresol Alters Neutrophil Function in Dogs.

    Science.gov (United States)

    Bosco, Anelise Maria; Pereira, Priscila Preve; Almeida, Breno Fernando Martins; Narciso, Luis Gustavo; Dos Santos, Diego Borba; Santos-Neto, Álvaro José Dos; Ferreira, Wagner Luis; Ciarlini, Paulo César

    2016-05-01

    To achieve a clearer understanding of the mechanisms responsible for neutrophil dysfunction recently described in dogs with chronic renal failure (CRF), the plasma concentrations of free p-cresol in healthy dogs (n = 20) and those with CRF (n = 20) were compared. The degree of correlation was determined between plasma levels of p-cresol and markers of oxidative stress and function of neutrophils in these dogs. The effect of this compound on oxidative metabolism and apoptosis was assessed in neutrophils isolated from 16 healthy dogs incubated in RPMI 1640 supplemented with p-cresol (0.405 mg/L) and compared with medium supplemented with uremic plasma (50%). To achieve this, the plasma concentration of p-cresol was quantified by liquid phase high-performance liquid chromatography. The neutrophil oxidative metabolism was determined using the probes hydroethidine and 2',7'-dichlorofluorescein diacetate and apoptosis was measured using Annexin V-PE by capillary flow cytometry. Compared with the healthy dogs, uremic dogs presented higher concentrations of free p-cresol, greater oxidative stress, and neutrophils primed for accelerated apoptosis. The free p-cresol induced in neutrophils from healthy dogs increased apoptosis and decreased reactive oxygen species production. We conclude that the health status presented during uremia concomitant with the increase in plasma free p-cresol can contribute to the presence of immunosuppression in dogs with CRF.

  20. The Role of Neutrophil Activation in Pathogenesis of Preeclampsia

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    To investigate the effect of neutrophil activation on pathogenesis of pre-eclampsia, neutrophil activation was examined by using flow cytometry to assess the CD11b expression and the levels of plasma endothelin-1 (ET-1) and serum NO-2 were also measured by using non-equilibrium radioimmunoassay and by Griess assay in 29 pregnant women with pre-eclampsia and 31 normal pregnant women at third trimester. The expression of neutrophil CD11b was significantly elevated in women with pre-eclampsia as compared with that of normal pregnant women at third trimester. The mean fluorescence index of CD11b was 438.38±179.91 and 326.97±170.14 respectively (P<0.05). The plasma ET-1 level and serum NO 2 concentration in pre-eclampsic women (63.69±48.33 pg/ml and 20.03±4.77 μmol/L, respectively) were both significantly increased as compared with those in the normal pregnancy women (29.98±20.25 pg/ml and 15.47±5.47 μmol/L, respectively, P<0.01). The neutrophil CD11b expression was significantly elevated in pre-eclampsia. The increased neutrophil activation may cause the damage of vascular endothelium and result in NO release compensatory increase in endothelial cells, suggesting that the neutrophil activation may play a key role in pathogenesis of pre-eclampsia.

  1. [Purification and antimicrobial activity of human neutrophil defensins].

    Science.gov (United States)

    Qu, X; Wang, A

    1991-11-01

    Neutrophils are one of the weapons of host defenses against microbial infection. Their ability to kill the invading microorganisms depends on two principle mechanisms. One depends on production of reactive oxygen intermediates (ROI) by stimulated neutrophils, and the other depends on the delivery of antimicrobial contents of the neutrophils' cytoplasmic granules, oxygen-independent. The defensins have the highest concentration in the neutrophils, and the broadest antimicrobial spectrum, being capable of killing gram-positive and gram-negative bacteria, fungi and some envelope viruses. We purified human defensins from the neutrophils' granules by gel permeation chromatography and SDS-preparative acrylamide gel electrophoresis. The molecular weight of human defensins is between 3,000-4,000 daltons. After testing, C. neoformans was susceptible to these defensins. Under condition of 37 degrees C, pH 7.4 and low ionic strength, antifungal activity by human defensins was related to its concentration and incubating time. All of these illustrate that nonoxidative killing mechanism of neutrophils, especially the function of defensins is very important in host defenses.

  2. Roles of lung epithelium in neutrophil recruitment during pneumococcal pneumonia.

    Science.gov (United States)

    Yamamoto, Kazuko; Ahyi, Ayele-Nati N; Pepper-Cunningham, Zachary A; Ferrari, Joseph D; Wilson, Andrew A; Jones, Matthew R; Quinton, Lee J; Mizgerd, Joseph P

    2014-02-01

    Epithelial cells line the respiratory tract and interface with the external world. Epithelial cells contribute to pulmonary inflammation, but specific epithelial roles have proven difficult to define. To discover unique epithelial activities that influence immunity during infection, we generated mice with nuclear factor-κB RelA mutated throughout all epithelial cells of the lung and coupled this approach with epithelial cell isolation from infected and uninfected lungs for cell-specific analyses of gene induction. The RelA mutant mice appeared normal basally, but in response to pneumococcus in the lungs they were unable to rapidly recruit neutrophils to the air spaces. Epithelial cells expressed multiple neutrophil-stimulating cytokines during pneumonia, all of which depended on RelA. Cytokine expression by nonepithelial cells was unaltered by the epithelial mutation of RelA. Epithelial cells were the predominant sources of CXCL5 and granulocyte-macrophage colony-stimulating factor (GM-CSF), whereas nonepithelial cells were major sources for other neutrophil-activating cytokines. Epithelial RelA mutation decreased whole lung levels of CXCL5 and GM-CSF during pneumococcal pneumonia, whereas lung levels of other neutrophil-recruiting factors were unaffected. Defective neutrophil recruitment in epithelial mutant mice could be rescued by administration of CXCL5 or GM-CSF. These results reveal a specialized immune function for the pulmonary epithelium, the induction of CXCL5 and GM-CSF, to accelerate neutrophil recruitment in the infected lung.

  3. Mycobacterium tuberculosis 19-kDa lipoprotein promotes neutrophil activation.

    Science.gov (United States)

    Neufert, C; Pai, R K; Noss, E H; Berger, M; Boom, W H; Harding, C V

    2001-08-01

    Certain microbial substances, e.g., LPS, can activate neutrophils or prime them to enhance their response to other activating agents, e.g., fMLP. We investigated the role of the Mycobacterium tuberculosis (MTB) 19-kDa lipoprotein in activation of human neutrophils. MTB 19-kDa lipoprotein initiated phenotypic changes characteristic of neutrophil activation, including down-regulation of CD62 ligand (L-selectin) and up-regulation of CD35 (CR1) and CD11b/CD18 (CR3, Mac-1). In addition, exposure of neutrophils to MTB 19-kDa lipoprotein enhanced the subsequent oxidative burst in response to fMLP as assessed by oxidation of dihydrorhodamine 123 (determined by flow cytometry). LPS also produced these effects with similar kinetics, but an oligodeoxynucleotide containing a CpG motif failed to induce any priming or activation response. Although the effects of LPS required the presence of serum, neutrophil activation by MTB 19-kDa lipoprotein occurred independently of serum factors, suggesting the involvement of different receptors and signaling mechanisms for LPS and MTB 19-kDa lipoprotein. Thus, MTB 19-kDa lipoprotein serves as a pathogen-associated molecular pattern that promotes neutrophil priming and activation.

  4. Human neutrophils facilitate tumor cell transendothelial migration.

    LENUS (Irish Health Repository)

    Wu, Q D

    2012-02-03

    Tumor cell extravasation plays a key role in tumor metastasis. However, the precise mechanisms by which tumor cells migrate through normal vascular endothelium remain unclear. In this study, using an in vitro transendothelial migration model, we show that human polymorphonuclear neutrophils (PMN) assist the human breast tumor cell line MDA-MB-231 to cross the endothelial barrier. We found that tumor-conditioned medium (TCM) downregulated PMN cytocidal function, delayed PMN apoptosis, and concomitantly upregulated PMN adhesion molecule expression. These PMN treated with TCM attached to tumor cells and facilitated tumor cell migration through different endothelial monolayers. In contrast, MDA-MB-231 cells alone did not transmigrate. FACScan analysis revealed that these tumor cells expressed high levels of intercellular adhesion molecule-1 (ICAM-1) but did not express CD11a, CD11b, or CD18. Blockage of CD11b and CD18 on PMN and of ICAM-1 on MDA-MB-231 cells significantly attenuated TCM-treated, PMN-mediated tumor cell migration. These tumor cells still possessed the ability to proliferate after PMN-assisted transmigration. These results indicate that TCM-treated PMN may serve as a carrier to assist tumor cell transendothelial migration and suggest that tumor cells can exploit PMN and alter their function to facilitate their extravasation.

  5. On Skew Circulant Type Matrices Involving Any Continuous Fibonacci Numbers

    Directory of Open Access Journals (Sweden)

    Zhaolin Jiang

    2014-01-01

    inverse matrices of them by constructing the transformation matrices. Furthermore, the maximum column sum matrix norm, the spectral norm, the Euclidean (or Frobenius norm, and the maximum row sum matrix norm and bounds for the spread of these matrices are given, respectively.

  6. Circulating Endothelial Microparticles in Diabetes Mellitus

    Directory of Open Access Journals (Sweden)

    A. F. Tramontano

    2010-01-01

    Full Text Available Background. Endothelial Microparticles (EMPs are small vesicles shed from activated or apoptotic endothelial cells and involved in cellular cross-talk. Whether EMP immunophenotypes vary according to stimulus in Diabetes Mellitus (DM is not known. We studied the cellular adhesion molecule (CAM profile of circulating EMPs in patients with and without Diabetes Mellitus type 2, who were undergoing elective cardiac catheterization. Methods and Results. EMPs were analyzed by flow cytometry. The absolute median number of EMPs (EMPs/L specific for CD31, CD105, and CD106 was significantly increased in the DM population. The ratio of CD62E/CD31 EMP populations reflected an apoptotic process. Conclusion. Circulating CD31+, CD105+, and CD106+ EMPs were significantly elevated in patients with DM. EMPs were the only independent predictors of DM in our study cohort. In addition, the EMP immunophenotype reflected an apoptotic process. Circulating EMPs may provide new options for risk assessment.

  7. Homocysteine enhances superoxide anion release and NADPH oxidase assembly by human neutrophils. Effects on MAPK activation and neutrophil migration.

    Science.gov (United States)

    Alvarez-Maqueda, Moisés; El Bekay, Rajaa; Monteseirín, Javier; Alba, Gonzalo; Chacón, Pedro; Vega, Antonio; Santa María, Consuelo; Tejedo, Juan R; Martín-Nieto, José; Bedoya, Francisco J; Pintado, Elisabeth; Sobrino, Francisco

    2004-02-01

    Hyperhomocysteinaemia has recently been recognized as a risk factor of cardiovascular disease. However, the action mechanisms of homocysteine (Hcy) are not well understood. Given that Hcy may be involved in the recruitment of monocytes and neutrophils to the vascular wall, we have investigated the role of Hcy in essential functions of human neutrophils. We show that Hcy increased superoxide anion (O2*-) release by neutrophils to the extracellular medium, and that this effect was inhibited by superoxide dismutase and diphenyleneiodonium (DPI), an inhibitor of NADPH oxidase activity. The enzyme from rat peritoneal macrophages displayed a similar response. These effects were accompanied by a time-dependent increased translocation of p47phox and p67phox subunits of NADPH oxidase to the plasma membrane. We also show that Hcy increased intracellular H2O2 production by neutrophils, that Hcy enhanced the activation and phosphorylation of mitogen-activated protein kinases (MAPKs), specifically p38-MAPK and ERK1/2, and that the migration of neutrophils was increased by Hcy. Present results are the first evidence that Hcy enhances the oxidative stress of neutrophils, and underscore the potential role of phagocytic cells in vascular wall injury through O2*- release in hyperhomocysteinaemia conditions.

  8. Compressed Sensing for Thoracic MRI with Partial Random Circulant Matrices

    Directory of Open Access Journals (Sweden)

    Hideaki Haneishi

    2012-03-01

    Full Text Available The use of Circulant matrix as the sensing matrix in compressed sensing (CS scheme has recently been proposed to overcome the limitation of random or partial Fourier matrices. Aside from reducing computational complexity, the use of circulant matrix for MR image offers the feasibility in hardware implementations. This paper presents the simulation of compressed sensing for thoracic MR imaging with circulant matrix as the sensing matrix. The comparisons of reconstruction of three different type MR images using circulant matrix are investigated in term of number of samples, number of iteration and signal to noise ratio (SNR. The simulation results showed that Circulant Matrix works efficiently for encoding the MR image of respiratory organ, especially for smooth and sparse image in spatial domain.

  9. The role of the thermohaline circulation in abrupt climate change.

    Science.gov (United States)

    Clark, Peter U; Pisias, Nicklas G; Stocker, Thomas F; Weaver, Andrew J

    2002-02-21

    The possibility of a reduced Atlantic thermohaline circulation in response to increases in greenhouse-gas concentrations has been demonstrated in a number of simulations with general circulation models of the coupled ocean-atmosphere system. But it remains difficult to assess the likelihood of future changes in the thermohaline circulation, mainly owing to poorly constrained model parameterizations and uncertainties in the response of the climate system to greenhouse warming. Analyses of past abrupt climate changes help to solve these problems. Data and models both suggest that abrupt climate change during the last glaciation originated through changes in the Atlantic thermohaline circulation in response to small changes in the hydrological cycle. Atmospheric and oceanic responses to these changes were then transmitted globally through a number of feedbacks. The palaeoclimate data and the model results also indicate that the stability of the thermohaline circulation depends on the mean climate state.

  10. Anti-HMGB1 Neutralizing Antibody Ameliorates Neutrophilic Airway Inflammation by Suppressing Dendritic Cell-Mediated Th17 Polarization

    Directory of Open Access Journals (Sweden)

    Fang Zhang

    2014-01-01

    Full Text Available We demonstrate that high mobility group box 1 protein (HMGB1 directs Th17 skewing by regulating dendritic cell (DC function. First, our in vitro studies reveal that recombinant HMGB1 (rHMGB1 activates myeloid DCs to produce IL-23 in vitro, and rHMGB1-activated DCs prime naïve lymphocytes to produce the Th17 cytokine IL-17A. Second, we demonstrate that anti-HMGB1 neutralizing antibody attenuates HMGB1 expression, neutrophilic inflammation, airway hyperresponsiveness, and Th17-related cytokine secretion in vivo by using a murine model of neutrophilic asthma induced by ovalbumin (OVA plus lipopolysaccharide (LPS. Furthermore, anti-HMGB1 neutralizing antibody decreases the number of Th17 cells in lung cells and suppresses the production of IL-23 by lung CD11C+ APCs. Finally, we show that intranasal adoptive transfer of rHMGB1-activated DCs was sufficient to restore lung neutrophilic inflammation and the Th17 response in a DC-driven model of asthma, whereas the transfer of rHMGB1 plus anti-HMGB1-treated mDCs significantly reduced these inflammation phenotypes. These data suggest, for the first time, that HMGB1 drives the DC-polarized Th17-type response in allergic lung inflammation and that blocking HMGB1 may benefit the attenuation of neutrophilic airway inflammation in asthma.

  11. Human neutrophils and oral microbiota: a constant tug-of-war between a harmonious and a discordant coexistence

    Science.gov (United States)

    Uriarte, Silvia M.; Edmisson, Jacob S.; Jimenez-Flores, Emeri

    2017-01-01

    Summary Neutrophils are a major component of the innate host response, and the outcome of the interaction between the oral microbiota and neutrophils is a key determinant of oral health status. The composition of the oral microbiome is very complex and different in health and disease. Neutrophils are constantly recruited to the oral cavity, and their protective role is highlighted in cases where their number or functional responses are impeded, resulting in different forms of periodontal disease. Periodontitis, one of the more severe and irreversible forms of periodontal disease, is a microbial-induced chronic inflammatory disease that affects the gingival tissues supporting the tooth. This chronic inflammatory disease is the result of a shift of the oral bacterial symbiotic community to a dysbiotic more complex community. Chronic inflammatory infectious diseases such as periodontitis can occur because the pathogens are able to evade or disable the innate immune system. In this review, we discuss how human neutrophils interact with both the symbiotic and the dysbiotic oral community; an understanding of which is essential to increase our knowledge of the periodontal disease process. PMID:27558341

  12. The fetal circulation.

    Science.gov (United States)

    Kiserud, Torvid; Acharya, Ganesh

    2004-12-30

    Accumulating data on the human fetal circulation shows the similarity to the experimental animal physiology, but with important differences. The human fetus seems to circulate less blood through the placenta, shunt less through the ductus venosus and foramen ovale, but direct more blood through the lungs than the fetal sheep. However, there are substantial individual variations and the pattern changes with gestational age. The normalised umbilical blood flow decreases with gestational age, and, at 28 to 32 weeks, a new level of development seems to be reached. At this stage, the shunting through the ductus venosus and the foramen ovale reaches a minimum, and the flow through the lungs a maximum. The ductus venosus and foramen ovale are functionally closely related and represent an important distributional unit for the venous return. The left portal branch represents a venous watershed, and, similarly, the isthmus aorta an arterial watershed. Thus, the fetal central circulation is a very flexible and adaptive circulatory system. The responses to increased afterload, hypoxaemia and acidaemia in the human fetus are equivalent to those found in animal studies: increased ductus venosus and foramen ovale shunting, increased impedance in the lungs, reduced impedance in the brain, increasingly reversed flow in the aortic isthmus and a more prominent coronary blood flow.

  13. Venous levels of shear support neutrophil-platelet adhesion and neutrophil aggregation in blood via P-selectin and beta2-integrin

    Science.gov (United States)

    Konstantopoulos, K.; Neelamegham, S.; Burns, A. R.; Hentzen, E.; Kansas, G. S.; Snapp, K. R.; Berg, E. L.; Hellums, J. D.; Smith, C. W.; McIntire, L. V.; Simon, S. I.

    1998-01-01

    BACKGROUND: After activation, platelets adhere to neutrophils via P-selectin and beta2-integrin. The molecular mechanisms and adhesion events in whole blood exposed to venous levels of hydrodynamic shear in the absence of exogenous activation remain unknown. METHODS AND RESULTS: Whole blood was sheared at approximately 100 s(-1). The kinetics of neutrophil-platelet adhesion and neutrophil aggregation were measured in real time by flow cytometry. P-selectin was upregulated to the platelet surface in response to shear and was the primary factor mediating neutrophil-platelet adhesion. The extent of neutrophil aggregation increased linearly with platelet adhesion to neutrophils. Blocking either P-selectin, its glycoprotein ligand PSGL-1, or both simultaneously by preincubation with a monoclonal antibody resulted in equivalent inhibition of neutrophil-platelet adhesion (approximately 30%) and neutrophil aggregation (approximately 70%). The residual amount of neutrophil adhesion was blocked with anti-CD11b/CD18. Treatment of blood with prostacyclin analogue ZK36374, which raises cAMP levels in platelets, blocked P-selectin upregulation and neutrophil aggregation to baseline. Complete abrogation of platelet-neutrophil adhesion required both ZK36374 and anti-CD18. Electron microscopic observations of fixed blood specimens revealed that platelets augmented neutrophil aggregation both by forming bridges between neutrophils and through contact-mediated activation. CONCLUSIONS: The results are consistent with a model in which venous levels of shear support platelet adherence to neutrophils via P-selectin binding PSGL-1. This interaction alone is sufficient to mediate neutrophil aggregation. Abrogation of platelet adhesion and aggregation requires blocking Mac-1 in addition to PSGL-1 or P-selectin. The described mechanisms are likely of key importance in the pathogenesis and progression of thrombotic disorders that are exacerbated by leukocyte-platelet aggregation.

  14. Survival and differentiation defects contribute to neutropenia in glucose-6-phosphatase-β (G6PC3) deficiency in a model of mouse neutrophil granulocyte differentiation.

    Science.gov (United States)

    Gautam, S; Kirschnek, S; Gentle, I E; Kopiniok, C; Henneke, P; Häcker, H; Malleret, L; Belaaouaj, A; Häcker, G

    2013-08-01

    Differentiation of neutrophil granulocytes (neutrophils) occurs through several steps in the bone marrow and requires a coordinate regulation of factors determining survival and lineage-specific development. A number of genes are known whose deficiency disrupts neutrophil generation in humans and in mice. One of the proteins encoded by these genes, glucose-6-phosphatase-β (G6PC3), is involved in glucose metabolism. G6PC3 deficiency causes neutropenia in humans and in mice, linked to enhanced apoptosis and ER stress. We used a model of conditional Hoxb8 expression to test molecular and functional differentiation as well as survival defects in neutrophils from G6PC3(-/-) mice. Progenitor lines were established and differentiated into neutrophils when Hoxb8 was turned off. G6PC3(-/-) progenitor cells underwent substantial apoptosis when differentiation was started. Transgenic expression of Bcl-XL rescued survival; however, Bcl-XL-protected differentiated cells showed reduced proliferation, immaturity and functional deficiency such as altered MAP kinase signaling and reduced cytokine secretion. Impaired glucose utilization was found and was associated with ER stress and apoptosis, associated with the upregulation of Bim and Bax; downregulation of Bim protected against apoptosis during differentiation. ER-stress further caused a profound loss of expression and secretion of the main neutrophil product neutrophil elastase during differentiation. Transplantation of wild-type Hoxb8-progenitor cells into irradiated mice allowed differentiation into neutrophils in the bone marrow in vivo. Transplantation of G6PC3(-/-) cells yielded few mature neutrophils in bone marrow and peripheral blood. Transgenic Bcl-XL permitted differentiation of G6PC3(-/-) cells in vivo. However, functional deficiencies and differentiation abnormalities remained. Differentiation of macrophages from Hoxb8-dependent progenitors was only slightly disturbed. A combination of defects in differentiation

  15. Number names and number understanding

    DEFF Research Database (Denmark)

    Ejersbo, Lisser Rye; Misfeldt, Morten

    2014-01-01

    through using mathematical names for the numbers such as one-ten-one for 11 and five-ten-six for 56. The project combines the renaming of numbers with supporting the teaching with the new number names. Our hypothesis is that Danish children have more difficulties learning and working with numbers, because...

  16. Burn injury reduces neutrophil directional migration speed in microfluidic devices.

    Directory of Open Access Journals (Sweden)

    Kathryn L Butler

    Full Text Available Thermal injury triggers a fulminant inflammatory cascade that heralds shock, end-organ failure, and ultimately sepsis and death. Emerging evidence points to a critical role for the innate immune system, and several studies had documented concurrent impairment in neutrophil chemotaxis with these post-burn inflammatory changes. While a few studies suggest that a link between neutrophil motility and patient mortality might exist, so far, cumbersome assays have prohibited exploration of the prognostic and diagnostic significance of chemotaxis after burn injury. To address this need, we developed a microfluidic device that is simple to operate and allows for precise and robust measurements of chemotaxis speed and persistence characteristics at single-cell resolution. Using this assay, we established a reference set of migration speed values for neutrophils from healthy subjects. Comparisons with samples from burn patients revealed impaired directional migration speed starting as early as 24 hours after burn injury, reaching a minimum at 72-120 hours, correlated to the size of the burn injury and potentially serving as an early indicator for concurrent infections. Further characterization of neutrophil chemotaxis using this new assay may have important diagnostic implications not only for burn patients but also for patients afflicted by other diseases that compromise neutrophil functions.

  17. Demodex-associated bacterial proteins induce neutrophil activation.

    LENUS (Irish Health Repository)

    2012-02-01

    Background: Patients with rosacea demonstrate a higher density of Demodex mites in their skin than controls. A bacterium isolated from a Demodex mite from a patient with papulopustular rosacea (PPR) was previously shown to provoke an immune response in patients with PPR or ocular rosacea thus suggesting a possible role for bacterial proteins in the etiology of this condition. Objectives: To examine the response of neutrophils to proteins derived from a bacterium isolated from a Demodex mite. Methods: Bacterial cells were lysed and proteins were partially purified by AKTA-FPLC. Isolated neutrophils were exposed to bacterial proteins and monitored for alterations in migration, degranulation and cytokine production. Results: Neutrophils exposed to proteins from Bacillus cells demonstrated increased levels of migration and elevated release of MMP-9, an enzyme known to degrade collagen and cathelicidin, an antimicrobial peptide. In addition neutrophils exposed to the bacterial proteins demonstrated elevated rates of Il-8 and TNF-alpha production. Conclusions: Proteins produced by a bacterium isolated from a Demodex mite have the ability to increase the migration, degranulation and cytokine production abilities of neutrophils. These results suggest that bacteria may play a role in the inflammatory erythema associated with rosacea.

  18. Nitrite attenuated peroxynitrite and hypochlorite generation in activated neutrophils.

    Science.gov (United States)

    Ren, Xiaoming; Ding, Yun; Lu, Naihao

    2016-03-15

    Oxidative stress is usually considered as an important factor to the pathogenesis of various diseases. Peroxynitrite (ONOO(-)) and hypochlorite (OCl(-)) are formed in immune cells as a part of the innate host defense system, but excessive reactive oxygen species generation can cause progressive inflammation and tissue damage. It has been proven that through mediating nitric oxide (NO) homeostasis, inorganic nitrite (NO2(-)) shows organ-protective effects on oxidative stress and inflammation. However, the effects of NO2(-) on the function of immune cells were still not clear. The potential role of NO2(-) in modulating ONOO(-) and OCl(-) generation in neutrophil cells was investigated in this study. As an immune cell activator, lipopolysaccharide (LPS) increased both ONOO(-) and OCl(-) production in neutrophils, which was significantly attenuated by NO2(-). NO2(-) reduced superoxide (O2(·-)) generation via a NO-dependent mechanism and increased NO formation in activated neutrophils, suggesting a crucial role of O2(·-) in NO2(-)-mediated reduction of ONOO(-). Moreover, the reduced effect of NO2(-) on OCl(-) production was attributed to that NO2(-) reduced H2O2 production in activated neutrophils without influencing the release of myeloperoxidase (MPO), thus limiting OCl(-) production by MPO/H2O2 system. Therefore, NO2(-) attenuates ONOO(-) and OCl(-) formation in activated neutrophils, opening a new direction to modulate the inflammatory response.

  19. Absolute neutrophil values in malignant patients on cytotoxic chemotherapy.

    Science.gov (United States)

    Madu, A J; Ibegbulam, O G; Ocheni, S; Madu, K A; Aguwa, E N

    2011-01-01

    A total of eighty patients with various malignancies seen between September 2008 and April 2009 at the University of Nigeria Teaching Hospital (UNTH) Ituku Ozalla, Enugu, Nigeria, had their absolute neutrophil counts, done at Days 0 and 12 of the first cycle of their various chemotherapeutic regimens. They were adult patients who had been diagnosed of various malignancies, consisting of Breast cancer 36 (45%), Non-Hodgkin's lymphoma 8 (10%), Hodgkin's lymphoma 13 (16.25%), Colorectal carcinoma 6 (7.5%), Multiple myeloma 7 (8.75%), Cervical carcinoma 1 (1.25%) and other malignancies 9 (11.25%), Manual counting of absolute neutrophil count was done using Turks solution and improved Neubauer counting chamber and Galen 2000 Olympus microscope. The socio demographic data of the patients were assessed from a questionnaire. There were 27 males (33.75%) and 53 females (66.25%). Their ages ranged from 18 - 80 years with a median of 45 years. The mean absolute neutrophil count of the respondents pre-and post chemotherapy was 3.7 +/- 2.1 x 10(9)/L and 2.5 +/- 1.6 x 10(9)/L respectively. There were significant differences in both the absolute neutrophil count (p=0.00) compared to the pre-chemotherapy values. Chemotherapeutic combinations containing cyclophosphamide and Adriamycin were observed to cause significant reduction in absolute neutrophil.

  20. Inhibition of neutrophil activity improves cardiac function after cardiopulmonary bypass

    Directory of Open Access Journals (Sweden)

    Grünwald Frank

    2007-10-01

    Full Text Available Abstract Background The arterial in line application of the leukocyte inhibition module (LIM in the cardiopulmonary bypass (CPB limits overshooting leukocyte activity during cardiac surgery. We studied in a porcine model whether LIM may have beneficial effects on cardiac function after CPB. Methods German landrace pigs underwent CPB (60 min myocardial ischemia; 30 min reperfusion without (group I; n = 6 or with LIM (group II; n = 6. The cardiac indices (CI and cardiac function were analyzed pre and post CPB with a Swan-Ganz catheter and the cardiac function analyzer. Neutrophil labeling with technetium, scintigraphy, and histological analyses were done to track activated neutrophils within the organs. Results LIM prevented CPB-associated increase of neutrophil counts in peripheral blood. In group I, the CI significantly declined post CPB (post: 3.26 ± 0.31; pre: 4.05 ± 0.45 l/min/m2; p 2; p = 0.23. Post CPB, the intergroup difference showed significantly higher CI values in the LIM group (p Conclusion Our data provides strong evidence that LIM improves perioperative hemodynamics and cardiac function after CPB by limiting neutrophil activity and inducing accelerated sequestration of neutrophils in the spleen.

  1. IL-17 induces hyperalgesia via TNF-dependent neutrophil infiltration.

    Science.gov (United States)

    McNamee, Kay E; Alzabin, Saba; Hughes, Jane P; Anand, Praveen; Feldmann, Marc; Williams, Richard O; Inglis, Julia J

    2011-08-01

    Interleukin-17 (IL-17) and tumour necrosis factor-α (TNF) are critical in the pathogenesis of arthritis but their relationship during inflammatory pain has received limited attention. We aimed to establish whether IL-17 can induce hyperalgesia in acute conditions, and investigated the role of TNF in mediating the pain response. Hyperalgesia was elicited in C57BL/6 mice by injection of recombinant IL-17, TNF or vehicle into the plantar tissue. Elevated pain was measured by the Hargreaves test for thermal hyperalgesia and Linton incapacitance tester for weight-bearing change. Cellular infiltration during hyperalgesia was determined by histological analysis and myeloperoxidase assay. IL-17 was found to induce hyperalgesia, but this was dependent on neutrophil migration and TNF binding to TNF receptor 1 (TNFR1). Because TNF-induced hyperalgesia was also dependent on neutrophil migration, the relationship between the resident fibroblasts, the cytokines and the migrating neutrophils was further investigated. By means of an air pouch model of cell migration, it was established that IL-17-induced neutrophil infiltration was dependent of TNF/TNFR1 as this interaction was required for the induction of the chemokine keratinocyte chemoattractant. These findings suggest that IL-17 causes acute hyperalgesia indirectly by inducing TNF from resident cells. The subsequent production of keratinocyte chemoattractant then triggers neutrophil chemotaxis to the plantar tissue, releasing algesic mediators locally to sensitise the nerve.

  2. Human neutrophils produce extracellular traps against Paracoccidioides brasiliensis.

    Science.gov (United States)

    Mejía, Susana P; Cano, Luz E; López, Juan A; Hernandez, Orville; González, Ángel

    2015-05-01

    Neutrophils play an important role as effector cells and contribute to the resistance of the host against microbial pathogens. Neutrophils are able to produce extracellular traps (NETs) in response to medically important fungi, including Aspergillus spp., Candida albicans and Cryptococcus gattii. However, NET production in response to Paracoccidioides brasiliensis has yet to be studied. We have demonstrated that human neutrophils produce NETs against both conidia and yeasts of P. brasiliensis. Although the NADPH oxidase inhibitor diphenyleneiodonium chloride (DPI) did not alter NET production against conidia, it partially suppressed NET formation against P. brasiliensis yeasts. Cytochalasin D or IFN-γ did not affect the production of NETs against the fungus. Additionally, a mutant strain of P. brasiliensis with reduced expression of an alternative oxidase induced significantly higher levels of NETs in comparison with the WT strain. Finally, c.f.u. quantification of P. brasiliensis showed no significant differences when neutrophils were treated with DPI, DNase I or cytochalasin D as compared with untreated cells. These data establish that NET formation by human neutrophils appears to be either dependent or independent of reactive oxygen species production, correlating with the fungal morphotype used for stimulation. However, this mechanism was ineffective in killing the fungus.

  3. Neutrophil biology and the next generation of myeloid growth factors.

    Science.gov (United States)

    Dale, David C

    2009-01-01

    Neutrophils are the body's critical phagocytic cells for defense against bacterial and fungal infections; bone marrow must produce approximately 10 x 10(9) neutrophils/kg/d to maintain normal blood neutrophil counts. Production of neutrophils depends on myeloid growth factors, particularly granulocyte colony-stimulating factor (G-CSF). After the original phase of development, researchers modified these growth factors to increase their size and delay renal clearance, increase their biologic potency, and create unique molecules for business purposes. Pegylated G-CSF is a successful product of these efforts. Researchers have also tried to identify small molecules to serve as oral agents that mimic the parent molecules, but these programs have been less successful. In 2006, the European Medicines Agency established guidelines for the introduction of new biologic medicinal products claimed to be similar to reference products that had previously been granted marketing authorization in the European community, called bio-similars. Globally, new and copied versions of G-CSF and other myeloid growth factors are now appearing. Some properties of the myeloid growth factors are similar to other agents, offering opportunities for the development of alternative drugs and treatments. For example, recent research shows that hematopoietic progenitor cells can be mobilized with a chemokine receptor antagonist, chemotherapy, G-CSF, and granulocyte macrophage colony-stimulating factor. Advances in neutrophil biology coupled with better understanding and development of myeloid growth factors offer great promise for improving the care of patients with cancer and many other disorders.

  4. Entamoeba histolytica induces human neutrophils to form NETs.

    Science.gov (United States)

    Ventura-Juarez, J; Campos-Esparza, Mr; Pacheco-Yepez, J; López-Blanco, J A; Adabache-Ortíz, A; Silva-Briano, M; Campos-Rodríguez, R

    2016-08-01

    Entamoeba histolytica invades the intestine and other organs during the pathogenesis of amoebiasis. In the early stages, the host organism responds with an inflammatory infiltrate composed mostly of neutrophils. It has been reported that these immune cells, activated by E. histolytica, exert a protective role by releasing proteolytic enzymes and generating reactive oxygen/nitrogen species (ROS/RNS) and antimicrobial peptides. It is now known that neutrophils also produce neutrophil extracellular traps (NETs), which are able to damage and kill pathogens. Studies have shown that intracellular protozoan pathogens, including Toxoplasma gondi, Plasmodium falciparum and Leishmania spp, induce neutrophils to release NETs and are damaged by them. However, the action of this mechanism has not been explored in relation to E. histolytica trophozoites. Through scanning electron, epifluorescence microscopy and viability assays, we show for first time that during in vitro interaction with E. histolytica trophozoites, human neutrophils released NETs that covered amoebas and reduced amoebic viability. These NETs presented histones, myeloperoxidase and decondensed chromatin. The results suggest that NETs participate in the elimination of the parasite.

  5. Peripheral blood neutrophil cytokine hyper-reactivity in chronic periodontitis.

    Science.gov (United States)

    Ling, Martin R; Chapple, Iain L C; Matthews, John B

    2015-10-01

    Pro-inflammatory cytokine release (IL-8, IL-6, TNF-α, IL-1β) by peripheral blood neutrophils, isolated from periodontitis patients (before/after therapy) and matched controls, was determined after 18 h culture in the presence/absence of Escherichia coli LPS, opsonised Staphylococcus aureus, heat-killed Fusobacterium nucleatum and Porphyromonas gingivalis. All cultures demonstrated differences in the amounts of each cytokine detected (P IL-6 > TNF-α = IL-1β). Median cytokine release from unstimulated patient neutrophils was consistently, but non-significantly, higher than from control cells. Stimulated cytokine release from untreated patient neutrophils was also consistently higher than from control cells. This hyper-reactivity was significant for all tested cytokines when data for all stimuli were combined (P TNF-α), opsonised S. aureus (IL-8, TNF-α, IL-1β) and P. gingivalis (IL-8, IL-1β). Cytokine production by patient neutrophils did not reduce following successful non-surgical periodontal therapy and, except for responses to F. nucleatum, the cytokine hyper-reactivity detected pre-therapy was retained. These data demonstrate that chronic periodontitis is characterised by neutrophils that constitutively exhibit cytokine hyper-reactivity, the effects of which could modulate local and systemic inflammatory-immune responses and influence the risk and severity of periodontitis-associated systemic inflammatory diseases.

  6. Modelled Circulation In Storfjorden

    Science.gov (United States)

    Skogseth, R.; Asplin, L.

    The model area Storfjorden is situated between the islands Spitsbergen, Barentsöya and Edgeöya at the Svalbard Archipelago. The entrance of Storfjorden is defined by a shallow bank Storfjordbanken and some small islands Tusenöyane in southeast, and by an 115m deep sill at about 76 45' N in the south. Maximum depth in Storfjorden is 190m, which is surrounded by gradually shallower shelves in the north, the east and southeast. A steep bottom slope is present on the western side of Storfjorden. He- leysundet and Freemansundet, two sounds between respectively Spitsbergen and Bar- entsöya, and Barentsöya and Edgeöya, define two narrow and shallow entrances in the north and northeast connecting Storfjorden with the northwestern Barents Sea. Strong tidal currents exist in Heleysundet (4-5ms-1) and Freemansundet (2-3ms-1), but the general circulation in Storfjorden is not well known. The coastal current in Storfjor- den is cyclonic directed into Storfjorden south of Edgeöya from the East Spitsbergen Current and out of Storfjorden south of Spitsbergen where it is called Sørkappstrøm- men. A three-dimensional sigma layered numerical ocean model called Bergen Ocean Model (BOM) was used to simulate the circulation in Storfjorden with Freemansundet opened. Two simulations were carried out, one with heat flux (100 Wm-2) and one without heat flux from the ocean to the atmosphere. The heat flux was applied only in the proper fjord area north of the sill and not outside as a crude approximation of the effects of a polynya in the sea ice cover during winter. Both simulations had a 4km horizontal resolution and 21 sigma layers. The model is forced by winds (from the NCEP reanalyzed fields) and tides. Initial fields are from the DNMI/IMR climatol- ogy. The model simulation without heat flux gave a circulation heavily dependent on tidal forcing, showing strong tidal currents up to 2ms-1 in Freemansundet, between Tusenöyane and on Storfjordbanken southwest of Edgeöya. Earlier

  7. Sensitivity of the Meridional Overturning Circulation to the Pattern of the Surface Density Flux

    Science.gov (United States)

    2010-09-01

    a better prognosis of anthropogenic climate change . Figure 1. Classical representation of the global thermohaline circulation and oceanic...modeling efforts and long-term strategy related to climate change . 15. NUMBER OF PAGES 105 14. SUBJECT TERMS Meridional Overturning Circulation ... Thermohaline Circulation , Thermocline, Residual-Mean Theory, Air-Sea Fluxes, Surface Density Flux , Mixed-Layer Density, Water-mass Transformation

  8. Differential regulation of neutrophil chemotaxis to IL-8 and fMLP by GM-CSF: lack of direct effect of oestradiol.

    Science.gov (United States)

    Shen, Li; Smith, Jennifer M; Shen, Zheng; Hussey, Stephen B; Wira, Charles R; Fanger, Michael W

    2006-02-01

    Neutrophils are a normal constituent of the female reproductive tract and their numbers increase in the late secretory phase of the menstrual cycle prior to menses. Several cytokines are produced in female reproductive tract tissue. In particular granulocyte-macrophage colony-stimulating factor (GM-CSF), a potent activator of neutrophils, is secreted in high concentrations by female reproductive tract epithelia. We previously observed that GM-CSF synergizes strongly with interleukin-8 (IL-8) in enhancing chemotaxis of neutrophils. Thus we investigated whether pretreatment of neutrophils with GM-CSF would prime subsequent chemotaxis to IL-8 in the absence of GM-CSF. Surprisingly, a 3-hr pulse of GM-CSF severely diminished chemotaxis to IL-8, whereas N-formyl-methyl-leucyl-phenylalanine (fMLP)-mediated chemotaxis was retained. Conversely, when cells were incubated without GM-CSF they retained IL-8-mediated migration but lost fMLP chemotaxis. These changes in chemotaxis did not correlate with expression of CXCR1, CXCR2 or formyl peptide receptor. However, IL-8-mediated phosphorylation of p44/42 mitogen-activated protein kinase was greatly reduced in neutrophils that no longer migrated to IL-8, and was diminished in cells that no longer migrated to fMLP. Oestradiol, which is reported by some to exert an anti-inflammatory effect on neutrophils, did not change the effects of GM-CSF. These data suggest that neutrophil function may be altered by cytokines such as GM-CSF through modulation of signalling and independently of surface receptor expression.

  9. Experimental study of natural circulation circuit

    Energy Technology Data Exchange (ETDEWEB)

    Lemos, Wanderley F.; Su, Jian, E-mail: wlemos@lasme.coppe.ufrj.br, E-mail: sujian@lasme.coppe.ufrj.br [Coordenacao dos Programas de Pos-Graduacao de Engenharia (LASME/COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Lab. de Simulacao e Metodos Numericos; Faccini, Jose L.H., E-mail: faccini@ien.gov.br [Instituto de Engenharia Nuclear (LTE/IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil). Lab. de Termo-Hidraulica Experimental

    2011-07-01

    This work presents an experimental study about fluid flows behavior in natural circulation, under conditions of single-phase flow. The experiment was performed through experimental thermal-hydraulic circuit built at IEN. This test equipment has performance similar to passive system of residual heat removal present in Advanced Pressurized Water Reactors (APWR). This experimental study aims to observing and analyzing the natural circulation phenomenon, using this experimental circuit that was dimensioned and built based on concepts of similarity and scale. This philosophy allows the analysis of natural circulation behavior in single-phase flow conditions proportionally to the functioning real conditions of a nuclear reactor. The experiment was performed through procedures to initialization of hydraulic feeding of primary and secondary circuits and electrical energizing of resistors installed inside heater. Power controller has availability to adjust values of electrical power to feeding resistors, in order to portray several conditions of energy decay of nuclear reactor in a steady state. Data acquisition system allows the measurement and monitoring of the evolution of the temperature in various points through thermocouples installed in strategic points along hydraulic circuit. The behavior of the natural circulation phenomenon was monitored by graphical interface on computer screen, showing the temperature evolutions of measuring points and results stored in digital spreadsheets. The results stored in digital spreadsheets allowed the getting of data to graphic construction and discussion about natural circulation phenomenon. Finally, the calculus of Reynolds number allowed the establishment for a correlation of friction in function of geometric scales of length, heights and cross section of tubing, considering a natural circulation flow throughout in the region of hot leg. (author)

  10. Sagan numbers

    OpenAIRE

    Mendonça, J. Ricardo G.

    2012-01-01

    We define a new class of numbers based on the first occurrence of certain patterns of zeros and ones in the expansion of irracional numbers in a given basis and call them Sagan numbers, since they were first mentioned, in a special case, by the North-american astronomer Carl E. Sagan in his science-fiction novel "Contact." Sagan numbers hold connections with a wealth of mathematical ideas. We describe some properties of the newly defined numbers and indicate directions for further amusement.

  11. Fibonacci numbers

    CERN Document Server

    Vorob'ev, Nikolai Nikolaevich

    2011-01-01

    Fibonacci numbers date back to an 800-year-old problem concerning the number of offspring born in a single year to a pair of rabbits. This book offers the solution and explores the occurrence of Fibonacci numbers in number theory, continued fractions, and geometry. A discussion of the ""golden section"" rectangle, in which the lengths of the sides can be expressed as a ration of two successive Fibonacci numbers, draws upon attempts by ancient and medieval thinkers to base aesthetic and philosophical principles on the beauty of these figures. Recreational readers as well as students and teacher

  12. Number names and number understanding

    DEFF Research Database (Denmark)

    Ejersbo, Lisser Rye; Misfeldt, Morten

    2014-01-01

    through using mathematical names for the numbers such as one-ten-one for 11 and five-ten-six for 56. The project combines the renaming of numbers with supporting the teaching with the new number names. Our hypothesis is that Danish children have more difficulties learning and working with numbers, because...... the Danish number names are more complicated than in other languages. Keywords: A research project in grade 0 and 1th in a Danish school, Base-10 system, two-digit number names, semiotic, cognitive perspectives....

  13. Doxycycline induced photodamage to human neutrophils and tryptophan

    Energy Technology Data Exchange (ETDEWEB)

    Sandberg, S.; Glette, J.; Hopen, G.; Solberg, C.O. (Haukeland Sykehus, Bergen (Norway))

    1984-01-01

    Neutrophil function were studied following irradiation (340-380 nm) of the cells in the presence of 22 ..mu..M doxycycline. At increasing light fluence the locomotion, chemiluminescence and glucose oxidation (by the hexose monophosphate shunt) of the neutrophils steadily decreased. The photodamage increased with increasing preincubation temperature and time and was enhanced in D/sub 2/O, reduced in azide and abolished in anaerobiosis. Superoxide dismutase, catalase or mannitol did not influence the photodamage. Photooxidation of tryptophan in the presence of doxycycline was increased 9-10-fold in D/sub 2/O and nearly abolished in the presence of 0.25 mM NaN/sub 3/, indicating that singlet oxygen is the most important reactive oxygen species in the doxycycline-induced photodamage. The results may explain some of the features of tetracycline-induced photosensitivity and why other authors have obtained diverging results when studying the influence of tetracyclines on neutrophil functions.

  14. An elucidation of neutrophil functions against Mycobacterium tuberculosis infection.

    Science.gov (United States)

    Morris, Devin; Nguyen, Thien; Kim, John; Kassissa, Christine; Khurasany, Melissa; Luong, Jennifer; Kasko, Sarah; Pandya, Shalin; Chu, Michael; Chi, Po-Ting; Ly, Judy; Lagman, Minette; Venketaraman, Vishwanath

    2013-01-01

    We characterized the functions of neutrophils in response to Mycobacterium tuberculosis (M. tb) infection, with particular reference to glutathione (GSH). We examined the effects of GSH in improving the ability of neutrophils to control intracellular M. tb infection. Our findings indicate that increasing the intracellular levels of GSH with a liposomal formulation of GSH (L-GSH) resulted in reduction in the levels of free radicals and increased acidification of M. tb containing phagosomes leading to the inhibition in the growth of M. tb. This inhibitory mechanism is dependent on the presence of TNF-α and IL-6. Our studies demonstrate a novel regulatory mechanism adapted by the neutrophils to control M. tb infection.

  15. An Elucidation of Neutrophil Functions against Mycobacterium tuberculosis Infection

    Directory of Open Access Journals (Sweden)

    Devin Morris

    2013-01-01

    Full Text Available We characterized the functions of neutrophils in response to Mycobacterium tuberculosis (M. tb infection, with particular reference to glutathione (GSH. We examined the effects of GSH in improving the ability of neutrophils to control intracellular M. tb infection. Our findings indicate that increasing the intracellular levels of GSH with a liposomal formulation of GSH (L-GSH resulted in reduction in the levels of free radicals and increased acidification of M. tb containing phagosomes leading to the inhibition in the growth of M. tb. This inhibitory mechanism is dependent on the presence of TNF-α and IL-6. Our studies demonstrate a novel regulatory mechanism adapted by the neutrophils to control M. tb infection.

  16. Light scattering by neutrophils: model, simulation, and experiment.

    Science.gov (United States)

    Orlova, Darya Yu; Yurkin, Maxim A; Hoekstra, Alfons G; Maltsev, Valeri P

    2008-01-01

    We studied the elastic light-scattering properties of human blood neutrophils, both experimentally and theoretically. The experimental study was performed with a scanning flow cytometer measuring the light-scattering patterns (LSPs) of individual cells over an angular range of 5-60 deg. We determined the absolute differential light-scattering cross sections of neutrophils. We also proposed an optical model for a neutrophil as a sphere filled by small spheres and prolate spheroids that correspond to granules and segmented nucleus, respectively. This model was used in simulations of LSPs using the discrete dipole approximation and different compositions of internal organelles. A comparison of experimentally measured and simulated LSPs gives a good qualitative agreement in LSP shape and quantitative agreement in overall magnitude of the differential light-scattering cross section.

  17. Neutrophils: the forgotten cell in JIA disease pathogenesis

    Directory of Open Access Journals (Sweden)

    Petty Howard R

    2007-06-01

    Full Text Available Abstract Juvenile idiopathic arthritis (JIA has long been assumed to be an autoimmune disease, triggered by aberrant recognition of "self" antigens by T-cells. However, systems biology approaches to this family of diseases have suggested complex interactions between innate and adaptive immunity that underlie JIA. In particular, new data suggest an important role for neutrophils in JIA pathogenesis. In this short review, we will discuss the new data that support a role for neutrophils in JIA, discuss regulatory functions that link neutrophils to adaptive immune responses, and discuss future areas of investigation. Above all else, we invite the reader to re-consider the use of the term "autoimmunity" as applied to the family of illnesses we collectively call JIA.

  18. North Atlantic Circulation

    Science.gov (United States)

    Molinari, R.; Bryan, K.; Schott, F.

    The intensity of the North Atlantic winddriven and thermohaline circulation and the close proximity of many oceanographic installations make the North Atlantic a particularly favored region of the world ocean from the standpoint of research in ocean circulation. Recent increases in available data and advances in numerical modeling techniques served as the impetus to convene a joint workshop of modelers and observers working on the North Atlantic with the Scientific Committee on Oceanic Research (SCOR) Working Group (WG) 68 (“North Atlantic Circulation”). Goals of the workshop were to provide an update on data sets and models and to discuss the poleward heat flux problem and possible monitoring strategies. The joint Workshop/SCOR WG-68 meeting was convened by F. Schott (chairman of the working group; Rosenstiel School of Marine and Atmospheric Science, Miami, Fla.), K. Bryan (National Oceanic and Atmospheric Administration/ Geophysical Fluid Dynamics Laboratory (NOAA/GFDL)), and R. Molinari (NOAA/Atlantic Oceanographic and Meteorological Laboratory (NOAA/AOML)).

  19. Circulation of Stars

    Science.gov (United States)

    Boitani, P.

    2016-01-01

    Since the dawn of man, contemplation of the stars has been a primary impulse in human beings, who proliferated their knowledge of the stars all over the world. Aristotle sees this as the product of primeval and perennial “wonder” which gives rise to what we call science, philosophy, and poetry. Astronomy, astrology, and star art (painting, architecture, literature, and music) go hand in hand through millennia in all cultures of the planet (and all use catasterisms to explain certain phenomena). Some of these developments are independent of each other, i.e., they take place in one culture independently of others. Some, on the other hand, are the product of the “circulation of stars.” There are two ways of looking at this. One seeks out forms, the other concentrates on the passing of specific lore from one area to another through time. The former relies on archetypes (for instance, with catasterism), the latter constitutes a historical process. In this paper I present some of the surprising ways in which the circulation of stars has occurred—from East to West, from East to the Far East, and from West to East, at times simultaneously.

  20. Neutrophil Extracellular Traps and Its Implications in Inflammation: An Overview

    Science.gov (United States)

    Delgado-Rizo, Vidal; Martínez-Guzmán, Marco A.; Iñiguez-Gutierrez, Liliana; García-Orozco, Alejandra; Alvarado-Navarro, Anabell; Fafutis-Morris, Mary

    2017-01-01

    In addition to physical barriers, neutrophils are considered a part of the first line of immune defense. They can be found in the bloodstream, with a lifespan of 6–8 h, and in tissue, where they can last up to 7 days. The mechanisms that neutrophils utilize for host defense are phagocytosis, degranulation, cytokine production, and, the most recently described, neutrophil extracellular trap (NET) production. NETs are DNA structures released due to chromatin decondensation and spreading, and they thus occupy three to five times the volume of condensed chromatin. Several proteins adhere to NETs, including histones and over 30 components of primary and secondary granules, among them components with bactericidal activity such as elastase, myeloperoxidase, cathepsin G, lactoferrin, pentraxin 3, gelatinase, proteinase 3, LL37, peptidoglycan-binding proteins, and others with bactericidal activity able to destroy virulence factors. Three models for NETosis are known to date. (a) Suicidal NETosis, with a duration of 2–4 h, is the best described model. (b) In vital NETosis with nuclear DNA release, neutrophils release NETs without exhibiting loss of nuclear or plasma membrane within 5–60 min, and it is independent of reactive oxygen species (ROS) and the Raf/MERK/ERK pathway. (c) The final type is vital NETosis with release of mitochondrial DNA that is dependent on ROS and produced after stimuli with GM-CSF and lipopolysaccharide. Recent research has revealed neutrophils as more sophisticated immune cells that are able to precisely regulate their granular enzymes release by ion fluxes and can release immunomodulatory cytokines and chemokines that interact with various components of the immune system. Therefore, they can play a key role in autoimmunity and in autoinflammatory and metabolic diseases. In this review, we intend to show the two roles played by neutrophils: as a first line of defense against microorganisms and as a contributor to the pathogenesis of

  1. Spontaneous neutrophil activation in HTLV-1 infected patients

    Directory of Open Access Journals (Sweden)

    Jaqueline B. Guerreiro

    2005-12-01

    Full Text Available Human T cell lymphotropic Virus type-1 (HTLV-1 induces lymphocyte activation and proliferation, but little is known about the innate immune response due to HTLV-1 infection. We evaluated the percentage of neutrophils that metabolize Nitroblue tetrazolium (NBT to formazan in HTLV-1 infected subjects and the association between neutrophil activation and IFN-gamma and TNF-alpha levels. Blood was collected from 35 HTLV-1 carriers, from 8 patients with HAM/TSP (HTLV-1- associated myelopathy; 22 healthy individuals were evaluated for spontaneous and lipopolysaccharide (LPS-stimulated neutrophil activity (reduction of NBT to formazan. The production of IFN-gamma and TNF-alpha by unstimulated mononuclear cells was determined by ELISA. Spontaneous NBT levels, as well as spontaneous IFN-gamma and TNF-alpha production, were significantly higher (p<0.001 in HTLV-1 infected subjects than in healthy individuals. A trend towards a positive correlation was noted, with increasing percentage of NBT positive neutrophils and levels of IFN-gamma. The high IFN-gamma producing HTLV-1 patient group had significantly greater NBT than healthy controls, 43±24% and 17±4.8% respectively (p< 0.001, while no significant difference was observed between healthy controls and the low IFN-gamma-producing HTLV-1 patient group (30±20%. Spontaneous neutrophil activation is another marker of immune perturbation resulting from HTLV-1 infection. In vivo activation of neutrophils observed in HTLV-1 infected subjects is likely to be the same process that causes spontaneous IFN-gamma production, or it may partially result from direct IFN-gamma stimulation.

  2. Neuroimmunoendocrine regulation of the prion protein in neutrophils.

    Science.gov (United States)

    Mariante, Rafael M; Nóbrega, Alberto; Martins, Rodrigo A P; Areal, Rômulo B; Bellio, Maria; Linden, Rafael

    2012-10-12

    The prion protein (PrP(C)) is a cell surface protein expressed mainly in the nervous system. In addition to the role of its abnormal conformer in transmissible spongiform encephalopathies, normal PrP(C) may be implicated in other degenerative conditions often associated with inflammation. PrP(C) is also present in cells of hematopoietic origin, including T cells, dendritic cells, and macrophages, and it has been shown to modulate their functions. Here, we investigated the impact of inflammation and stress on the expression and function of PrP(C) in neutrophils, a cell type critically involved in both acute and chronic inflammation. We found that systemic injection of LPS induced transcription and translation of PrP(C) in mouse neutrophils. Up-regulation of PrP(C) was dependent on the serum content of TGF-β and glucocorticoids (GC), which, in turn, are contingent on the activation of the hypothalamic-pituitary-adrenal axis in response to systemic inflammation. GC and TGF-β, either alone or in combination, directly up-regulated PrP(C) in neutrophils, and accordingly, the blockade of GC receptors in vivo curtailed the LPS-induced increase in the content of PrP(C). Moreover, GC also mediated up-regulation of PrP(C) in neutrophils following noninflammatory restraint stress. Finally, neutrophils with up-regulated PrP(C) presented enhanced peroxide-dependent cytotoxicity to endothelial cells. The data demonstrate a novel interplay of the nervous, endocrine, and immune systems upon both the expression and function of PrP(C) in neutrophils, which may have a broad impact upon the physiology and pathology of various organs and systems.

  3. Eulerian numbers

    CERN Document Server

    Petersen, T Kyle

    2015-01-01

    This text presents the Eulerian numbers in the context of modern enumerative, algebraic, and geometric combinatorics. The book first studies Eulerian numbers from a purely combinatorial point of view, then embarks on a tour of how these numbers arise in the study of hyperplane arrangements, polytopes, and simplicial complexes. Some topics include a thorough discussion of gamma-nonnegativity and real-rootedness for Eulerian polynomials, as well as the weak order and the shard intersection order of the symmetric group. The book also includes a parallel story of Catalan combinatorics, wherein the Eulerian numbers are replaced with Narayana numbers. Again there is a progression from combinatorics to geometry, including discussion of the associahedron and the lattice of noncrossing partitions. The final chapters discuss how both the Eulerian and Narayana numbers have analogues in any finite Coxeter group, with many of the same enumerative and geometric properties. There are four supplemental chapters throughout, ...

  4. Epinephrine enhances platelet-neutrophil adhesion in whole blood in vitro.

    NARCIS (Netherlands)

    Horn, N.A.; Anastase, D.M.; Hecker, K.E.; Baumert, J.H.; Robitzsch, T.; Rossaint, R.

    2005-01-01

    Previous studies showed that alpha- or beta-adrenoceptor stimulation by catecholamines influenced neutrophil function, cytokine liberation, and platelet aggregability. We investigated whether adrenergic stimulation with epinephrine also alters platelet-neutrophil adhesion. This might be of specific

  5. Increased neutrophil priming and sensitization before commencing cardiopulmonary bypass in cardiac surgical patients

    NARCIS (Netherlands)

    Gu, YJ; Schoen, P; Tigchelaar, [No Value; Loef, BG; Ebels, T; Rankin, AJ; van Oeveren, W

    2002-01-01

    Background. Neutrophil activation is implicated in postoperative complications in patients having cardiac surgery with cardiopulmonary bypass (CPB). This study was designed to determine the temporal fluctuations in the primability of neutrophils in the preoperative, intraoperative, and postoperative

  6. A Neutrophil Phenotype Model for Extracorporeal Treatment of Sepsis.

    Directory of Open Access Journals (Sweden)

    Alexander D Malkin

    2015-10-01

    Full Text Available Neutrophils play a central role in eliminating bacterial pathogens, but may also contribute to end-organ damage in sepsis. Interleukin-8 (IL-8, a key modulator of neutrophil function, signals through neutrophil specific surface receptors CXCR-1 and CXCR-2. In this study a mechanistic computational model was used to evaluate and deploy an extracorporeal sepsis treatment which modulates CXCR-1/2 levels. First, a simplified mechanistic computational model of IL-8 mediated activation of CXCR-1/2 receptors was developed, containing 16 ODEs and 43 parameters. Receptor level dynamics and systemic parameters were coupled with multiple neutrophil phenotypes to generate dynamic populations of activated neutrophils which reduce pathogen load, and/or primed neutrophils which cause adverse tissue damage when misdirected. The mathematical model was calibrated using experimental data from baboons administered a two-hour infusion of E coli and followed for a maximum of 28 days. Ensembles of parameters were generated using a Bayesian parallel tempering approach to produce model fits that could recreate experimental outcomes. Stepwise logistic regression identified seven model parameters as key determinants of mortality. Sensitivity analysis showed that parameters controlling the level of killer cell neutrophils affected the overall systemic damage of individuals. To evaluate rescue strategies and provide probabilistic predictions of their impact on mortality, time of onset, duration, and capture efficacy of an extracorporeal device that modulated neutrophil phenotype were explored. Our findings suggest that interventions aiming to modulate phenotypic composition are time sensitive. When introduced between 3-6 hours of infection for a 72 hour duration, the survivor population increased from 31% to 40-80%. Treatment efficacy quickly diminishes if not introduced within 15 hours of infection. Significant harm is possible with treatment durations ranging from 5

  7. Human neutrophils dump Candida glabrata after intracellular killing.

    Science.gov (United States)

    Essig, Fabian; Hünniger, Kerstin; Dietrich, Stefanie; Figge, Marc Thilo; Kurzai, Oliver

    2015-11-01

    Interaction between fungal pathogens and human phagocytes can lead to remarkably variable outcomes, ranging from intracellular killing to prolonged survival and replication of the pathogen in the host cell. Using live cell imaging we observed primary human neutrophils that release phagocytosed Candida glabrata yeast cells after intracellular killing. This process, for which we propose the name "dumping", adds a new outcome to phagocyte-fungus interaction which may be of potential immunological importance as it allows professional antigen presenting cells to take up and process neutrophil-inactivated pathogens that in their viable state are able to evade intracellular degradation in these cells.

  8. [Murine peritoneal neutrophil activation upon tungsten nanoparticles exposure in vivo].

    Science.gov (United States)

    Martinova, E A; Baranov, V I

    2014-01-01

    Two examples of tungsten carbide nanoparticles (d = 15 nm, 50 nm) and tungsten carbide nanoparticles with 8% cobalt (d = 50 nm) have been found to induce the neutrophil activation 3 h and 36 h after intraperitoneal administration in the doses 0.005; 0.025; 0.05; 0.25; 0.5; 1; 2.5 and 5 microgram per 1 gram body weight to FVB mice. Neutrophil activation was calculated based on the CD11b and S100 antigen expression. Effect of nanoparticles is bimodal for all tested examples.

  9. Local Rheology of Human Neutrophils Investigated Using Atomic Force Microscopy

    Directory of Open Access Journals (Sweden)

    Yong J. Lee, Dipika Patel, Soyeun Park

    2011-01-01

    Full Text Available During the immune response, neutrophils display localized mechanical events by interacting with their environment through the micro-vascular transit, trans-endothelial, and trans-epithelial migration. Nano-mechanical studies of human neutrophils on localized nano-domains could provide the essential information for understanding their immune responsive functions. Using the Atomic Force Microscopy (AFM - based micro-rheology, we have investigated rheological properties of the adherent human neutrophils on local nano-domains. We have applied the modified Hertz model to obtain the viscoelastic moduli from the relatively thick body regions of the neutrophils. In addition, by using more advanced models to account for the substrate effects, we have successfully characterized the rheological properties of the thin leading and tail regions as well. We found a regional difference in the mechanical compliances of the adherent neutrophils. The central regions of neutrophils were significantly stiffer (1,548 ± 871 Pa than the regions closer to the leading edge (686 ± 801 Pa, while the leading edge and the tail (494 ± 537 Pa regions were mechanically indistinguishable. The frequency-dependent elastic and viscous moduli also display a similar regional difference. Over the studied frequency range (100 to 300 Hz, the complex viscoelastic moduli display the partial rubber plateau behavior where the elastic moduli are greater than the viscous moduli for a given frequency. The non-disparaging viscous modulus indicates that the neutrophils display a viscoelastic dynamic behavior rather than a perfect elastic behavior like polymer gels. In addition, we found no regional difference in the structural damping coefficient between the leading edge and the cell body. Thus, we conclude that despite the lower loss and storage moduli, the leading edges of the human neutrophils display partially elastic properties similar to the cell body. These results suggest that the

  10. Killing by neutrophil extracellular traps: fact or folklore?

    Science.gov (United States)

    Menegazzi, Renzo; Decleva, Eva; Dri, Pietro

    2012-02-02

    Neutrophil extracellular traps (NETs) are DNA structures released by dying neutrophils and claimed to constitute a new microbicidal mechanism. Killing by NET-forming cells is ascribed to these structures because it is prevented by preincubation with DNase, which has been shown to dismantle NETs, before addition of the target microorganisms. Curiously, the possibility that the microorganisms ensnared in NETs are alive has not been considered. Using Staphylococcus aureus and Candida albicans blastospores, we demonstrate that the microorganisms captured by NETs and thought to be killed are alive because they are released and recovered in cell medium by incubation with DNase. It is concluded that NETs entrap but do not kill microbes.

  11. Genetic Deletion and Pharmacological Inhibition of PI3Kγ Reduces Neutrophilic Airway Inflammation and Lung Damage in Mice with Cystic Fibrosis-Like Lung Disease

    Directory of Open Access Journals (Sweden)

    Maria Galluzzo

    2015-01-01

    Full Text Available Purpose. Neutrophil-dominated airway inflammation is a key feature of progressive lung damage in cystic fibrosis (CF. Thus, reducing airway inflammation is a major goal to prevent lung damage in CF. However, current anti-inflammatory drugs have shown several limits. PI3Kγ plays a pivotal role in leukocyte recruitment and activation; in the present study we determined the effects of genetic deletion and pharmacologic inhibition of PI3Kγ on airway inflammation and structural lung damage in a mouse model of CF lung disease. Methods. βENaC overexpressing mice (βENaC-Tg were backcrossed with PI3Kγ-deficient (PI3KγKO mice. Tissue damage was assessed by histology and morphometry and inflammatory cell number was evaluated in bronchoalveolar lavage fluid (BALF. Furthermore, we assessed the effect of a specific PI3Kγ inhibitor (AS-605240 on inflammatory cell number in BALF. Results. Genetic deletion of PI3Kγ decreased neutrophil numbers in BALF of PI3KγKO/βENaC-Tg mice, and this was associated with reduced emphysematous changes. Treatment with the PI3Kγ inhibitor AS-605240 decreased the number of neutrophils in BALF of βENaC-Tg mice, reproducing the effect observed with genetic deletion of the enzyme. Conclusions. These results demonstrate the biological efficacy of both genetic deletion and pharmacological inhibition of PI3Kγ in reducing chronic neutrophilic inflammation in CF-like lung disease in vivo.

  12. Redundant contribution of myeloperoxidase-dependent systems to neutrophil-mediated killing of Escherichia coli.

    OpenAIRE

    Rosen, H; Michel, B R

    1997-01-01

    Neutrophil microbicidal activity is a consequence of overlapping antimicrobial systems that vary in prominence according to the conditions of the neutrophil-microbe interaction, the nature of the microbe, and its metabolic state. In this study, normal, myeloperoxidase-deficient, and respiratory burst-deficient (chronic granulomatous disease [CGD]) neutrophils killed Escherichia coli with equivalent, high efficiencies. Killing by CGD and myeloperoxidase-deficient neutrophils was not augmented ...

  13. Plasma neutrophil elastase and elafin imbalance is associated with acute respiratory distress syndrome (ARDS development.

    Directory of Open Access Journals (Sweden)

    Zhaoxi Wang

    Full Text Available BACKGROUND: We conducted an exploratory study of genome-wide gene expression in whole blood and found that the expression of neutrophil elastase inhibitor (PI3, elafin was down-regulated during the early phase of ARDS. Further analyses of plasma PI3 levels revealed a rapid decrease during early ARDS development. PI3 and secretory leukocyte proteinase inhibitor (SLPI are important low-molecular-weight proteinase inhibitors produced locally at neutrophil infiltration site in the lung. In this study, we tested the hypothesis that an imbalance between neutrophil elastase (HNE and its inhibitors in blood is related to the development of ARDS. METHODOLOGY/PRINCIPAL FINDINGS: PI3, SLPI, and HNE were measured in plasma samples collected from 148 ARDS patients and 63 critical ill patients at risk for ARDS (controls. Compared with the controls, the ARDS patients had higher HNE, but lower PI3, at the onset of ARDS, resulting in increased HNE/PI3 ratio (mean = 14.5; 95% CI, 10.9-19.4, P<0.0001, whereas plasma SLPI was not associated with the risk of ARDS development. Although the controls had elevated plasma PI3 and HNE, their HNE/PI3 ratio (mean = 6.5; 95% CI, 4.9-8.8 was not significantly different from the healthy individuals (mean = 3.9; 95% CI, 2.7-5.9. Before the onset (7-days period prior to ARDS diagnosis, we only observed significantly elevated HNE, but the HNE-PI3 balance remained normal. With the progress from prior to the onset of ARDS, the plasma level of PI3 declined, whereas HNE was maintained at a higher level, tilting the balance toward more HNE in the circulation as characterized by an increased HNE/PI3 ratio. In contrast, three days after ICU admission, there was a significant drop of HNE/PI3 ratio in the at-risk controls. CONCLUSIONS/SIGNIFICANCE: Plasma profiles of PI3, HNE, and HNE/PI3 may be useful clinical biomarkers in monitoring the development of ARDS.

  14. Lost circulation technology development status

    Energy Technology Data Exchange (ETDEWEB)

    Glowka, D.A.; Schafer, D.M.; Loeppke, G.E.; Scott, D.D.; Wernig, M.D.; Wright, E.K.

    1992-07-01

    Lost circulation is the loss of drilling fluid from the wellbore to fractures or pores in the rock formation. In geothermal drilling, lost circulation is often a serious problem that contributes greatly to the cost of the average geothermal well. The Lost Circulation Technology Development Program is sponsored at Sandia National Laboratories by the US Department of Energy. The goal of the program is to reduce lost circulation costs by 30--50% through the development of mitigation and characterization technology. This paper describes the technical progress made in this program during the period April 1991--March 1992. 8 refs.

  15. Percutaneous interventions in Fontan circulation

    Directory of Open Access Journals (Sweden)

    Eduardo Franco

    2015-09-01

    Conclusions: Interventional catheterization procedures are often necessary to reach and maintain the fragile Fontan circulation, mainly in patients with right morphology systemic ventricles and fenestrated Fontan conduits.

  16. File list: His.Bld.05.AllAg.Neutrophils [Chip-atlas[Archive

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  16. Two independent killing mechanisms of Candida albicans by human neutrophils: evidence from innate immunity defects

    NARCIS (Netherlands)

    Gazendam, R.P.; Hamme, J.L. van; Tool, A.T.; Houdt, M. van; Verkuijlen, P.J.; Herbst, M.; Liese, J.G.; Veerdonk, F.L. van de; Roos, D.; Berg, T.K. van den; Kuijpers, T.W.

    2014-01-01

    Invasive fungal infections, accompanied by high rates of mortality, represent an increasing problem in medicine. Neutrophils are the major effector immune cells in fungal killing. Based on studies with neutrophils from patients with defined genetic defects, we provide evidence that human neutrophils

  17. Staphylococcus aureus SaeR/S-regulated factors reduce human neutrophil reactive oxygen species production

    NARCIS (Netherlands)

    Guerra, Fermin E.; Addison, Conrad B.; de Jong, Nienke W M; Azzolino, Joseph; Pallister, Kyler B.; van Strijp, Jos A G; Voyich, Jovanka M.

    2016-01-01

    Neutrophils are the first line of defense after a pathogen has breached the epithelial barriers, and unimpaired neutrophil functions are essential to clear infections. Staphylococcus aureus is a prevalent human pathogen that is able to withstand neutrophil killing, yet the mechanisms used by S. aure

  18. Functional Characterization of Neutrophils from Nine-Banded Armadillos (Dasypus novemcicntus; Edentata, Dasypodidae Infected with Microfilariae

    Directory of Open Access Journals (Sweden)

    Marcela López-Hurtado

    2006-01-01

    Full Text Available The neutrophils from uninfected armadillos have adequate phagocytic and bacteriocidal activity, but diminished chemotactic activity. However, endocytic activity from armadillo neutrophils infected with bacteria, parasites or viruses is unknown. This report shows that neutrophils from armadillos infected with microfilariae displayed deficiencies in their bacteriocidal mechanisms and TNF-like production, but not in their endocytic capacity.

  19. Elevated levels of circulating DNA in cardiovascular disease patients: metagenomic profiling of microbiome in the circulation.

    Science.gov (United States)

    Dinakaran, Vasudevan; Rathinavel, Andiappan; Pushpanathan, Muthuirulan; Sivakumar, Ramamoorthy; Gunasekaran, Paramasamy; Rajendhran, Jeyaprakash

    2014-01-01

    Cardiovascular diseases (CVDs) are the leading cause of death worldwide. An expanding body of evidence supports the role of human microbiome in the establishment of CVDs and, this has gained much attention recently. This work was aimed to study the circulating human microbiome in CVD patients and healthy subjects. The levels of circulating cell free DNA (circDNA) was higher in CVD patients (n = 80) than in healthy controls (n = 40). More specifically, the relative levels of circulating bacterial DNA and the ratio of 16S rRNA/β-globin gene copy numbers were higher in the circulation of CVD patients than healthy individuals. In addition, we found a higher circulating microbial diversity in CVD patients (n = 3) in comparison to healthy individuals (n = 3) by deep shotgun sequencing. At the phylum level, we observed a dominance of Actinobacteria in CVD patients, followed by Proteobacteria, in contrast to that in healthy controls, where Proteobacteria was predominantly enriched, followed by Actinobacteria. The circulating virome in CVD patients was enriched with bacteriophages with a preponderance of Propionibacterium phages, followed by Pseudomonas phages and Rhizobium phages in contrast to that in healthy individuals, where a relatively greater abundance of eukaryotic viruses dominated by Lymphocystis virus (LCV) and Torque Teno viruses (TTV) was observed. Thus, the release of bacterial and viral DNA elements in the circulation could play a major role leading to elevated circDNA levels in CVD patients. The increased circDNA levels could be either the cause or consequence of CVD incidence, which needs to be explored further.

  20. Clearance of circulating activated platelets in polycythemia vera and essential thrombocythemia.

    Science.gov (United States)

    Maugeri, Norma; Malato, Simona; Femia, Eti A; Pugliano, Mariateresa; Campana, Lara; Lunghi, Francesca; Rovere-Querini, Patrizia; Lussana, Federico; Podda, Gianmarco; Cattaneo, Marco; Ciceri, Fabio; Manfredi, Angelo A

    2011-09-22

    Essential thrombocythemia (ET) and polycythemia vera (PV) are characterized by persistent platelet activation. The mechanisms involved in their clearance are poorly characterized. In the present study, we report that leukocytes were actively involved in platelet disposal in 51 patients with ET and 30 with PV, but not in 70 age- and sex-matched controls. The fraction of circulating neutrophils and monocytes that had phagocytosed platelets, as assessed by flow cytometry, was significantly higher in patients with PV or ET, independently of hydroxyurea treatment, than in controls. Platelet phagocytosis by circulating leukocytes was confirmed by confocal and electron microscopy. The lack of effect of hydroxyurea, which disrupts the P-selectin/P-selectin glycoprotein ligand 1 (PSGL-1) interaction, suggests a P-selectin-independent mechanism. This hypothesis was confirmed in an ad hoc animal model based on the in vivo injection of activated platelets from P-selectin(+/+) and P-selectin(-/-) mice. P-selectin expression was associated with an earlier and effective clearance of platelets by neutrophils. A second delayed, P-selectin-independent phase actively involved monocytes. Our results suggest that phagocytic clearance of platelets by leukocytes occurs in PV and ET, possibly involving P-selectin-dependent and -independent pathways, thus representing a novel mechanism to remove activated platelets from the circulation.

  1. Elimination of neutrophils in zymosan-induced ankle inflammation by etoposide

    Directory of Open Access Journals (Sweden)

    Viktoriya I. Milanova

    2014-12-01

    Full Text Available Neutrophils play a crucial role in the pathogenesis of joint inflammatory diseases such as rheumatoid arthritis (RA. Therefore their elimination and/or a functional inhibition might have beneficial or even therapeutic effects in these diseases. In the present study we exploited the cytotoxic action of etoposide to deplete neutrophils. We administrated the drug twice (at day -3 and day -1 to SCID mice having intact innate immunity and a fail in T- and B-cell maturation. Ankle inflammation was induced by the injection of zymosan (ZY. Joint damage was evaluated by histology grading system for cell infiltration and proteoglycan loss and degree of cartilage erosion. The frequencies of mature Ly6G+CD11b+ cells in bone marrow (BM were monitored at days -4, -2 and 0 by flow cytometry. At day 7 of ankle inflammation the amounts of pro-inflammatory cytokines tumor necrosis factor (TNF-α and interleukin (IL-17 were measured by enzyme-linked immunosorbent assay (ELISA. Histological analysis of the joint sections showed decreased scores for cell infiltration and cartilage proteoglycan loss and reduced cartilage erosion in drug-treated zymosan injected mice in comparison to untreated group with ankle inflammation. Etoposide diminished cell numbers in BM, inhibits granulopoiesis triggered by zymosan and decreased the frequencies of mature Ly6G+CD11b+ cells in BM and eliminated Ly6G+ cells from blood and synovial fluid. We observed reduced TNF-α and impaired IL-17 production in etoposide-treated ZY group. Our data provide a proof-of principle that the elimination of neutrophils might be exploited in a design of new therapeutic approaches for joint inflammatory diseases.

  2. IL-1α-induced microvascular endothelial cells promote neutrophil killing by increasing MMP-9 concentration and lysozyme activity.

    Science.gov (United States)

    Liu, Xiaoye; Dong, Hong; Wang, Mingming; Gao, Ying; Zhang, Tao; Hu, Ge; Duan, Huiqing; Mu, Xiang

    2016-02-01

    The recruitment of neutrophils by endothelial cells during infection has been extensively studied, but little is known about the regulation of neutrophils activity by endothelial cells. To examine the role of microvascular endothelial cells in neutrophil killing, we established a transmigration model using rat intestinal microvascular endothelial cells (RIMVECs) and measured the extracellular and intracellular killing of Escherichia coli, Lactobacillus acidophilus, and Staphylococcus aureus by transendothelial neutrophils. We observed that blood neutrophils engulfed bacteria but did not kill them, and lipopolysaccharide- or hemolysin-injured RIMVECs inhibited the extracellular and intracellular bactericidal activity of transendothelial neutrophils. In comparison, interleukin-1α-induced RIMVECs promoted the extracellular and intracellular killing activity of transendothelial neutrophils and significantly increased MMP-9 concentration and lysozyme activity in transendothelial neutrophils (p neutrophils and bacterial toxin damage of endothelial cells led to reduction in bactericidal activity of transendothelial neutrophils. These findings offered new insight into the role of endothelial cells in the bactericidal activity of neutrophils.

  3. Separating the roles of nitrogen and oxygen in high pressure-induced blood-borne microparticle elevations, neutrophil activation, and vascular injury in mice.

    Science.gov (United States)

    Yang, Ming; Bhopale, Veena M; Thom, Stephen R

    2015-08-01

    An elevation in levels of circulating microparticles (MPs) due to high air pressure exposure and the associated inflammatory changes and vascular injury that occur with it may be due to oxidative stress. We hypothesized that these responses arise due to elevated partial pressures of N2 and not because of high-pressure O2. A comparison was made among high-pressure air, normoxic high-pressure N2, and high-pressure O2 in causing an elevation in circulating annexin V-positive MPs, neutrophil activation, and vascular injury by assessing the leakage of high-molecular-weight dextran in a murine model. After mice were exposed for 2 h to 790 kPa air, there were over 3-fold elevations in total circulating MPs as well as subgroups bearing Ly6G, CD41, Ter119, CD31, and CD142 surface proteins-evidence of neutrophil activation; platelet-neutrophil interaction; and vascular injury to brain, omentum, psoas, and skeletal muscles. Similar changes were found in mice exposed to high-pressure N2 using a gas mixture so that O2 partial pressure was the same as that of ambient air, whereas none of these changes occurred after exposures to 166 kPa O2, the same partial pressure that occurs during high-pressure air exposures. We conclude that N2 plays a central role in intra- and perivascular changes associated with exposure to high air pressure and that these responses appear to be a novel form of oxidative stress.

  4. Number theory

    CERN Document Server

    Andrews, George E

    1994-01-01

    Although mathematics majors are usually conversant with number theory by the time they have completed a course in abstract algebra, other undergraduates, especially those in education and the liberal arts, often need a more basic introduction to the topic.In this book the author solves the problem of maintaining the interest of students at both levels by offering a combinatorial approach to elementary number theory. In studying number theory from such a perspective, mathematics majors are spared repetition and provided with new insights, while other students benefit from the consequent simpl

  5. Magic Numbers

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    THE last digit of my home phone number in Beijing is 4. “So what?” European readers might ask.This was my attitude when I first lived in China; I couldn't understand why Chinese friends were so shocked at my indifference to the number 4. But China brings new discoveries every day, and I have since seen the light. I know now that Chinese people have their own ways of preserving their well being, and that they see avoiding the number 4 as a good way to stay safe.

  6. Preferential recruitment of neutrophils by endothelin-1 in acute lung inflammation induced by lipopolysaccharide or cigarette smoke

    Science.gov (United States)

    Bhavsar, Tapan; Liu, Xing Jian; Patel, Hardik; Stephani, Ralph; Cantor, Jerome O

    2008-01-01

    This study examined the role of endothelin-1 (ET-1) in recruiting inflammatory cells to the lung after induction of injury with either lipopolysaccharide (LPS) or cigarette smoke. Hamsters injected with either ET-1 or its precursor peptide (Big ET-1) prior to treatment with LPS or cigarette smoke had markedly increased concentrations of neutrophils in bronchoalveolar lavage fluid (BALF) despite a reduction in total numbers of BALF leukocytes. Furthermore, the effect of ET-1 on smoke-exposed animals was reversed by addition of an endothelin-A receptor antagonist. These results are consistent with preferential recruitment of neutrophils by ET-1, and suggest that inhibition of this proinflammatory mediator may decrease acute pulmonary inflammation associated with cigarette smoke and other pulmonary toxins. PMID:18990977

  7. Biological characterization of purified macrophage-derived neutrophil chemotactic factor

    Directory of Open Access Journals (Sweden)

    M. Dias-Baruffi

    1995-01-01

    Full Text Available We have recently described the purification of a 54 kDa acidic protein, identified as macrophage-derived neutrophil chemotactic factor (MNCF. This protein causes in vitro chemotaxis as well as in vivo neutrophil migration even in animals treated with dexamethasone. This in vivo chemotactic activity of MNCF in animals pretreated with dexamethasone is an uncommon characteristic which discriminates MNCF from known chemotactic cytokines. MNCF is released in the supernatant by macrophage monolayers stimulated with lipopolysaccharide (LPS. In the present study, we describe some biological characteristics of homogenous purified MNCF. When assayed in vitro, MNCF gave a bell-shaped dose–response curve. This in vitro activity was shown to be caused by haptotaxis. Unlike N-formyl-methionylleucyl- phenylalanine (FMLP or interleukin 8 (IL-8, the chemotactic activity of MNCF in vivo and in vitro, was inhibited by preincubation with D-galactose but not with D-mannose. In contrast with IL-8, MNCF did not bind to heparin and antiserum against IL-8 was ineffective in inhibiting its chemotactic activity. These data indicate that MNCF induces neutrophil migration through a carbohydrate recognition property, but by a mechanism different from that of the known chemokines. It is suggested that MNCF may be an important mediator in the recruitment of neutrophils via the formation of a substrate bound chemotactic gradient (haptotaxis in the inflamed tissues.

  8. Light scattering by neutrophils: Model, simulation, and experiment

    NARCIS (Netherlands)

    Orlova, D.Y.; Yurkin, M.A.; Hoekstra, A.G.; Maltsev, V.P.

    2008-01-01

    We studied the elastic light-scattering properties of human blood neutrophils, both experimentally and theoretically. The experimental study was performed with a scanning flow cytometer measuring the light-scattering patterns (LSPs) of individual cells over an angular range of 5-60 deg. We determine

  9. Activity of neutrophil elastase reflects the progression of acute pancreatitis

    DEFF Research Database (Denmark)

    Novovic, Srdan; Andersen, Anders M; Nord, Magnus

    2013-01-01

    Abstract Objective. Neutrophil elastase (NE) concentration is associated with progression of acute pancreatitis (AP), but measuring total NE concentration includes biologically inactive NE. This study aims to investigate the relationship between NE activity and the aetiology and severity of AP...... was associated with predicted severity of AP and AP-associated respiratory failure. Specific NE inhibitors may have therapeutic potential in acute pancreatitis....

  10. Physiological concentrations of leptin do not affect human neutrophils.

    NARCIS (Netherlands)

    Kamp, V.M.; Langereis, J.D.; Aalst, C.W. van; Linden, J. van der; Ulfman, L.H.; Koenderman, L.

    2013-01-01

    Leptin is an adipokine that is thought to be important in many inflammatory diseases, and is known to influence the function of several leukocyte types. However, no clear consensus is present regarding the responsiveness of neutrophils for this adipokine. In this study a 2D DIGE proteomics approach

  11. Systems biology of neutrophil differentiation and immune response

    DEFF Research Database (Denmark)

    Theilgaard-Mönch, Kim; Porse, Bo T; Borregaard, Niels

    2005-01-01

    Systems biology has emerged as a new scientific field, which aims at investigating biological processes at the genomic and proteomic levels. Recent studies have unravelled aspects of neutrophil differentiation and immune responses at the systems level using high-throughput technologies...

  12. Surface acoustic waves enhance neutrophil killing of bacteria.

    Science.gov (United States)

    Loike, John D; Plitt, Anna; Kothari, Komal; Zumeris, Jona; Budhu, Sadna; Kavalus, Kaitlyn; Ray, Yonatan; Jacob, Harold

    2013-01-01

    Biofilms are structured communities of bacteria that play a major role in the pathogenicity of bacteria and are the leading cause of antibiotic resistant bacterial infections on indwelling catheters and medical prosthetic devices. Failure to resolve these biofilm infections may necessitate the surgical removal of the prosthetic device which can be debilitating and costly. Recent studies have shown that application of surface acoustic waves to catheter surfaces can reduce the incidence of infections by a mechanism that has not yet been clarified. We report here the effects of surface acoustic waves (SAW) on the capacity of human neutrophils to eradicate S. epidermidis bacteria in a planktonic state and within biofilms. Utilizing a novel fibrin gel system that mimics a tissue-like environment, we show that SAW, at an intensity of 0.3 mW/cm(2), significantly enhances human neutrophil killing of S. epidermidis in a planktonic state and within biofilms by enhancing human neutrophil chemotaxis in response to chemoattractants. In addition, we show that the integrin CD18 plays a significant role in the killing enhancement observed in applying SAW. We propose from out data that this integrin may serve as mechanoreceptor for surface acoustic waves enhancing neutrophil chemotaxis and killing of bacteria.

  13. In vivo involvement of polymorphonuclear neutrophils in Leishmania infantum infection

    Directory of Open Access Journals (Sweden)

    Le Fichoux Yves

    2001-08-01

    Full Text Available Abstract Background The role of lymphocytes in the specific defence against L. infantum has been well established, but the part played by polynuclear neutrophil (PN cells in controlling visceral leishmaniasis was much less studied. In this report we examine in vivo the participation of PN in early and late phases of infection by L. infantum. Results Promastigote phagocytosis and killing occurs very early after infection, as demonstrated by electron microscopy analyses which show in BALB/c mouse spleen, but not in liver, numerous PN harbouring ultrastructurally degraded parasites. It is shown, using mAb RB6-8C5 directed against mature mouse granulocytes, that in chronically infected mice, long-term PN depletion did not enhance parasite counts neither in liver nor in spleen, indicating that these cells are not involved in the late phase of L. infantum infection. In acute stage of infection, in mouse liver, where L. infantum load is initially larger than that in spleen but resolves spontaneously, there was no significant effect of neutrophils depletion. By contrast, early in infection the neutrophil cells crucially contributed to parasite killing in spleen, since PN depletion, performed before and up to 7 days after the parasite inoculation, resulted in a ten-fold increase of parasite burden. Conclusions Taken together these data show that neutrophil cells contribute to the early control of the parasite growth in spleen but not in liver and that these cells have no significant effect late in infection in either of these target organs.

  14. Surface acoustic waves enhance neutrophil killing of bacteria.

    Directory of Open Access Journals (Sweden)

    John D Loike

    Full Text Available Biofilms are structured communities of bacteria that play a major role in the pathogenicity of bacteria and are the leading cause of antibiotic resistant bacterial infections on indwelling catheters and medical prosthetic devices. Failure to resolve these biofilm infections may necessitate the surgical removal of the prosthetic device which can be debilitating and costly. Recent studies have shown that application of surface acoustic waves to catheter surfaces can reduce the incidence of infections by a mechanism that has not yet been clarified. We report here the effects of surface acoustic waves (SAW on the capacity of human neutrophils to eradicate S. epidermidis bacteria in a planktonic state and within biofilms. Utilizing a novel fibrin gel system that mimics a tissue-like environment, we show that SAW, at an intensity of 0.3 mW/cm(2, significantly enhances human neutrophil killing of S. epidermidis in a planktonic state and within biofilms by enhancing human neutrophil chemotaxis in response to chemoattractants. In addition, we show that the integrin CD18 plays a significant role in the killing enhancement observed in applying SAW. We propose from out data that this integrin may serve as mechanoreceptor for surface acoustic waves enhancing neutrophil chemotaxis and killing of bacteria.

  15. PKC-δ activation in neutrophils promotes fungal clearance.

    Science.gov (United States)

    Li, Xun; Cullere, Xavier; Nishi, Hiroshi; Saggu, Gurpanna; Durand, Enrique; Mansour, Michael K; Tam, Jenny M; Song, Xiu-Yu; Lin, Xin; Vyas, Jatin M; Mayadas, Tanya

    2016-09-01

    The C-type lectin receptor dectin-1 and the integrin Mac-1 have key roles in controlling fungal infection. Here, we demonstrate that dectin-1- and Mac-1-induced activation of protein kinase Cδ in neutrophils, independent of the Card9 adaptor, is required for reactive oxygen species production and for intracellular killing upon Candida albicans uptake. Protein kinase Cδ was also required for zymosan-induced cytokine generation in neutrophils. In macrophages, protein kinase Cδ deficiency prevented fungi-induced reactive oxygen species generation but had no effect on activation of TGF-β-activated kinase-1, an effector of Card9, or nuclear factor κB activation, nor did it affect phagolysosomal maturation, autophagy, or intracellular C. albicans killing. In vivo, protein kinase Cδ-deficient mice were highly susceptible to C. albicans and Aspergillus fumigatus infection, which was partially rescued with adoptively transferred wild-type neutrophils. Thus, protein kinase Cδ activation downstream of dectin-1 and Mac-1 has an important role in neutrophil, but not macrophage, functions required for host defense against fungal pathogens.

  16. Chemokine CXCL1 mediated neutrophil recruitment: Role of glycosaminoglycan interactions.

    Science.gov (United States)

    Sawant, Kirti V; Poluri, Krishna Mohan; Dutta, Amit K; Sepuru, Krishna Mohan; Troshkina, Anna; Garofalo, Roberto P; Rajarathnam, Krishna

    2016-09-14

    The chemokine CXCL1/MGSA plays a pivotal role in the host immune response by recruiting and activating neutrophils for microbial killing at the tissue site. CXCL1 exists reversibly as monomers and dimers, and mediates its function by binding glycosaminoglycans (GAG) and CXCR2 receptor. We recently showed that both monomers and dimers are potent CXCR2 agonists, the dimer is the high-affinity GAG ligand, lysine and arginine residues located in two non-overlapping domains mediate GAG interactions, and there is extensive overlap between GAG and receptor-binding domains. To understand how these structural properties influence in vivo function, we characterized peritoneal neutrophil recruitment of a trapped monomer and trapped dimer and a panel of WT lysine/arginine to alanine mutants. Monomers and dimers were active, but WT was more active indicating synergistic interactions promote recruitment. Mutants from both domains showed reduced GAG heparin binding affinities and reduced neutrophil recruitment, providing compelling evidence that both GAG-binding domains mediate in vivo trafficking. Further, mutant of a residue that is involved in both GAG binding and receptor signaling showed the highest reduction in recruitment. We conclude that GAG interactions and receptor activity of CXCL1 monomers and dimers are fine-tuned to regulate neutrophil trafficking for successful resolution of tissue injury.

  17. Peripheral neutrophil functions and cell signalling in crohn's disease

    NARCIS (Netherlands)

    R. Somasundaram (Rajesh); V.J.A.A. Nuij (Veerle); C.J. van der Woude (Janneke); E.J. Kuipers (Ernst); M.P. Peppelenbosch (Maikel); G.M. Fuhler (Gwenny)

    2013-01-01

    textabstractThe role of the innate immunity in the pathogenesis of Crohn's disease (CD), an inflammatory bowel disease, is a subject of increasing interest. Neutrophils (PMN) are key members of the innate immune system which migrate to sites of bacterial infection and initiate the defence against mi

  18. Superoxide anion production by neutrophils in myelodysplastic syndromes (preleukemia.

    Directory of Open Access Journals (Sweden)

    Takahashi,Isao

    1988-02-01

    Full Text Available Superoxide anion (O2- production by neutrophils from 14 untreated patients with acute nonlymphocytic leukemia (ANLL was significantly less than that of healthy controls (4.93 +/- 1.99 vx 6.20 +/- 1.53 nmol/min/10(6 neutrophils, p less than 0.05. In 10 patients with myelodysplastic syndrome (MDS, however, it was not significantly different from the control level although 6 of the 10 patients had low levels, when individual patients were compared with the lower limit of the control range. An inverse correlation between the O2- production of neutrophils and the percentage of leukemic cells in the marrow existed in ANLL (r = -0.55, p less than 0.01, but not in MDS. Three of 4 MDS patients who died of pneumonia prior to leukemic conversion showed a low level of O2- production. The impaired O2- production by neutrophils from some MDS patients, probably due to the faulty differentiation from leukemic clones, may be one of the causes of enhanced susceptibility to infection.

  19. Nice numbers

    CERN Document Server

    Barnes, John

    2016-01-01

    In this intriguing book, John Barnes takes us on a journey through aspects of numbers much as he took us on a geometrical journey in Gems of Geometry. Similarly originating from a series of lectures for adult students at Reading and Oxford University, this book touches a variety of amusing and fascinating topics regarding numbers and their uses both ancient and modern. The author intrigues and challenges his audience with both fundamental number topics such as prime numbers and cryptography, and themes of daily needs and pleasures such as counting one's assets, keeping track of time, and enjoying music. Puzzles and exercises at the end of each lecture offer additional inspiration, and numerous illustrations accompany the reader. Furthermore, a number of appendices provides in-depth insights into diverse topics such as Pascal’s triangle, the Rubik cube, Mersenne’s curious keyboards, and many others. A theme running through is the thought of what is our favourite number. Written in an engaging and witty sty...

  20. Antimicrobial peptides and nitric oxide production by neutrophils from periodontitis subjects.

    Science.gov (United States)

    Mariano, F S; Campanelli, A P; Nociti Jr, F H; Mattos-Graner, R O; Gonçalves, R B

    2012-11-01

    Neutrophils play an important role in periodontitis by producing nitric oxide (NO) and antimicrobial peptides, molecules with microbicidal activity via oxygen-dependent and -independent mechanisms, respectively. It is unknown whether variation in the production of antimicrobial peptides such as LL-37, human neutrophil peptides (HNP) 1-3, and NO by neutrophils influences the pathogenesis of periodontal diseases. We compared the production of these peptides and NO by lipopolysaccharide (LPS)-stimulated neutrophils isolated from healthy subjects and from patients with periodontitis. Peripheral blood neutrophils were cultured with or without Aggregatibacter actinomycetemcomitans-LPS (Aa-LPS), Porphyromonas gingivalis-LPS (Pg-LPS) and Escherichia coli-LPS (Ec-LPS). qRT-PCR was used to determine quantities of HNP 1-3 and LL-37 mRNA in neutrophils. Amounts of HNP 1-3 and LL-37 proteins in the cell culture supernatants were also determined by ELISA. In addition, NO levels in neutrophil culture supernatants were quantitated by the Griess reaction. Neutrophils from periodontitis patients cultured with Aa-LPS, Pg-LPS and Ec-LPS expressed higher HNP 1-3 mRNA than neutrophils from healthy subjects. LL-37 mRNA expression was higher in neutrophils from patients stimulated with Aa-LPS. Neutrophils from periodontitis patients produced significantly higher LL-37 protein levels than neutrophils from healthy subjects when stimulated with Pg-LPS and Ec-LPS, but no difference was observed in HNP 1-3 production. Neutrophils from periodontitis patients cultured or not with Pg-LPS and Ec-LPS produced significantly lower NO levels than neutrophils from healthy subjects. The significant differences in the production of LL-37 and NO between neutrophils from healthy and periodontitis subjects indicate that production of these molecules might influence individual susceptibility to important periodontal pathogens.

  1. Antimicrobial peptides and nitric oxide production by neutrophils from periodontitis subjects

    Directory of Open Access Journals (Sweden)

    F.S. Mariano

    2012-11-01

    Full Text Available Neutrophils play an important role in periodontitis by producing nitric oxide (NO and antimicrobial peptides, molecules with microbicidal activity via oxygen-dependent and -independent mechanisms, respectively. It is unknown whether variation in the production of antimicrobial peptides such as LL-37, human neutrophil peptides (HNP 1-3, and NO by neutrophils influences the pathogenesis of periodontal diseases. We compared the production of these peptides and NO by lipopolysaccharide (LPS-stimulated neutrophils isolated from healthy subjects and from patients with periodontitis. Peripheral blood neutrophils were cultured with or without Aggregatibacter actinomycetemcomitans-LPS (Aa-LPS, Porphyromonas gingivalis-LPS (Pg-LPS and Escherichia coli-LPS (Ec-LPS. qRT-PCR was used to determine quantities of HNP 1-3 and LL-37 mRNA in neutrophils. Amounts of HNP 1-3 and LL-37 proteins in the cell culture supernatants were also determined by ELISA. In addition, NO levels in neutrophil culture supernatants were quantitated by the Griess reaction. Neutrophils from periodontitis patients cultured with Aa-LPS, Pg-LPS and Ec-LPS expressed higher HNP 1-3 mRNA than neutrophils from healthy subjects. LL-37 mRNA expression was higher in neutrophils from patients stimulated with Aa-LPS. Neutrophils from periodontitis patients produced significantly higher LL-37 protein levels than neutrophils from healthy subjects when stimulated with Pg-LPS and Ec-LPS, but no difference was observed in HNP 1-3 production. Neutrophils from periodontitis patients cultured or not with Pg-LPS and Ec-LPS produced significantly lower NO levels than neutrophils from healthy subjects. The significant differences in the production of LL-37 and NO between neutrophils from healthy and periodontitis subjects indicate that production of these molecules might influence individual susceptibility to important periodontal pathogens.

  2. Circulation in a Short Cylindrical Couette System

    Energy Technology Data Exchange (ETDEWEB)

    Akira Kageyama; Hantao Ji; Jeremy Goodman

    2003-07-08

    In preparation for an experimental study of magnetorotational instability (MRI) in liquid metal, we explore Couette flows having height comparable to the gap between cylinders, centrifugally stable rotation, and high Reynolds number. Experiments in water are compared with numerical simulations. The flow is very different from that of an ideal, infinitely long Couette system. Simulations show that endcaps co-rotating with the outer cylinder drive a strong poloidal circulation that redistributes angular momentum. Predicted toroidal flow profiles agree well with experimental measurements. Spin-down times scale with Reynolds number as expected for laminar Ekman circulation; extrapolation from two-dimensional simulations at Re less than or equal to 3200 agrees remarkably well with experiment at Re approximately equal to 106. This suggests that turbulence does not dominate the effective viscosity. Further detailed numerical studies reveal a strong radially inward flow near both endcaps. After turning vertically along the inner cylinder, these flows converge at the midplane and depart the boundary in a radial jet. To minimize this circulation in the MRI experiment, endcaps consisting of multiple, differentially rotating rings are proposed. Simulations predict that an adequate approximation to the ideal Couette profile can be obtained with a few rings.

  3. TROPICAL METEOROLOGY & Climate: Hadley Circulation

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Jian; Vecchi, Gabriel A.

    2015-01-30

    The Hadley circulation, a prominent circulation feature characterized by rising air near the Equator and sinking air in the subtropics, defines the position of dry subtropical areas and is a fundamental regulator of the earth’s energy and momentum budgets. The character of the Hadley circulation, and its related precipitation regimes, exhibits variation and change in response to both climate variability and radiative forcing changes. The strength and position of the Hadley circulation change from year to year paced by El Niño and La Niña events. Over the last few decades of the twentieth century, the Hadley cell has expanded poleward in both hemispheres, with changes in atmospheric composition (including stratospheric ozone depletion and greenhouse gas increases) thought to have contributed to its expansion. This article introduces the basic phenomenology and driving mechanism of the Hadley circulation and discusses its variations under both natural and anthropogenic climate forcings.

  4. Sino-Danish Brain Circulation

    DEFF Research Database (Denmark)

    Bertelsen, Rasmus Gjedssø; Du, Xiangyun; Søndergaard, Morten Karnøe

    2014-01-01

    China is faced with urgent needs to develop an economically and environmentally sustainable economy based on innovation and knowledge. Brain circulation and research and business investments from the outside are central for this development. Sino-American brain circulation and research...... and investment by overseas researchers and entrepreneurs are well described. In that case, the US is the center of global R&D and S&T. However, the brain circulation and research and investments between a small open Scandinavian economy, such as Denmark, and the huge developing economy of China are not well...... understood. In this case, Denmark is very highly developed, but a satellite in the global R&D and S&T system. With time and the growth of China as a R&D and S&T power house, both Denmark and China will benefit from brain circulation between them. Such brain circulation is likely to play a key role in flows...

  5. Neutrophil dysfunction after thermal injury: alteration of phagolysosomal acidification in patients with large burns.

    Science.gov (United States)

    Bjerknes, R; Vindenes, H

    1989-04-01

    The neutrophil phagolysosomal acidification during phagocytosis of Staphylococcus aureus was examined in six patients with large burns, using a flow cytometric technique allowing the simultaneous measurement of phagocytosis and phagolysosomal pH. The kinetics of neutrophil phagolysosomal acidification were altered during the first 20 days following injury, as the initial alkalinization of the phagolysosomes documented in control neutrophils could not be demonstrated in patient cells. Only at discharge and follow-up were the kinetics of phagolysosomal acidification normal. In addition, measurements of neutrophil maximal phagolysosomal acidification showed a lower pH in patient phagolysosomes than in the controls during the first 5 days of hospitalization. The changes of phagolysosomal acidification did not correlate with the alterations of neutrophil maturity or phagocytic capacity. The results demonstrate alterations of an oxygen-independent microbicidal mechanism in neutrophils from patients with large burns, which may contribute to the reduced capacity of neutrophil intracellular killing following thermal injury.

  6. Ultrastructural observation of human neutrophils during apoptotic cell death triggered by Entamoeba histolytica.

    Science.gov (United States)

    Sim, Seobo; Kim, Kyeong Ah; Yong, Tai-Soon; Park, Soon-Jung; Im, Kyung-il; Shin, Myeong Heon

    2004-12-01

    Neutrophils are important effector cells against protozoan extracellular parasite Entamoeba histolytica, which causes amoebic colitis and liver abscess in human beings. Apoptotic cell death of neutrophils is an important event in the resolution of inflammation and parasite's survival in vivo. This study was undertaken to investigate the ultrastructural aspects of apoptotic cells during neutrophil death triggered by Entamoeba histolytica. Isolated human neutrophils from the peripheral blood were incubated with or without live trophozoites of E. histolytica and examined by transmission electron microscopy (TEM). Neutrophils incubated with E. histolytica were observed to show apoptotic characteristics, such as compaction of the nuclear chromatin and swelling of the nuclear envelop. In contrast, neutrophils incubated in the absence of the amoeba had many protrusions of irregular cell surfaces and heterogenous nuclear chromatin. Therefore, it is suggested that Entamoeba-induced neutrophil apoptosis contribute to prevent unwanted tissue inflammation and damage in the amoeba-invaded lesions in vivo.

  7. Neutrophil-derived MRP-14 is up-regulated in infectious osteomyelitis and stimulates osteoclast generation.

    Science.gov (United States)

    Dapunt, Ulrike; Giese, Thomas; Maurer, Susanne; Stegmaier, Sabine; Prior, Birgit; Hänsch, G Maria; Gaida, Matthias M

    2015-10-01

    Bone infections of patients with joint replacement by endoprosthesis (so called "periprosthetic joint infection") pose a severe problem in the field of orthopedic surgery. The diagnosis is often difficult, and treatment is, in most cases, complicated and prolonged. Patients often require an implant exchange surgery, as the persistent infection and the accompanying inflammation lead to tissue damage with bone degradation and consequently, to a loosening of the implant. To gain insight into the local inflammatory process, expression of the proinflammatory cytokine MRP-14, a major content of neutrophils, and its link to subsequent bone degradation was evaluated. We found MRP-14 prominently expressed in the affected tissue of patients with implant-associated infection, in close association with the chemokine CXCL8 and a dense infiltrate of neutrophils and macrophages. In addition, the number of MRP-14-positive cells correlated with the presence of bone-resorbing osteoclasts. MRP-14 plasma concentrations were significantly higher in patients with implant-associated infection compared with patients with sterile inflammation or healthy individuals, advocating MRP-14 as a novel diagnostic marker. A further biologic activity of MRP-14 was detected: rMRP-14 directly induced the differentiation of monocytes to osteoclasts, thus linking the inflammatory response in implant infections with osteoclast generation, bone degradation, and implant loosening.

  8. Negative Numbers

    Science.gov (United States)

    Galbraith, Mary J.

    1974-01-01

    Examination of models for representing integers demonstrates that formal operational thought is required for establishing the operations on integers. Advocated is the use of many models for introducing negative numbers but, apart from addition, it is recommended that operations on integers be delayed until the formal operations stage. (JP)

  9. Numbers, Please!

    Science.gov (United States)

    Thelin, John R.

    2013-01-01

    What topic would you choose if you had the luxury of writing forever? In this article, John Thelin provides his response: He would opt to write about the history of higher education in a way that relies on quantitative data. "Numbers, please!" is his research request in taking on a longitudinal study of colleges and universities over…

  10. A novel method for high-throughput detection and quantification of neutrophil extracellular traps reveals ROS-independent NET release with immune complexes.

    Science.gov (United States)

    Kraaij, Tineke; Tengström, Fredrik C; Kamerling, Sylvia W A; Pusey, Charles D; Scherer, H Ulrich; Toes, Rene E M; Rabelink, Ton J; van Kooten, Cees; Teng, Y K Onno

    2016-06-01

    A newly-described first-line immune defence mechanism of neutrophils is the release of neutrophil extracellular traps (NETs). Immune complexes (ICxs) induce low level NET release. As such, the in vitro quantification of NETs is challenging with current methodologies. In order to investigate the role of NET release in ICx-mediated autoimmune diseases, we developed a highly sensitive and automated method for quantification of NETs. After labelling human neutrophils with PKH26 and extracellular DNA with Sytox green, cells are fixed and automatically imaged with 3-dimensional confocal laser scanning microscopy (3D-CLSM). NET release is then quantified with digital image analysis whereby the NET amount (Sytox green area) is corrected for the number of imaged neutrophils (PKH26 area). A high sensitivity of the assay is achieved by a) significantly augmenting the area of the well imaged (11%) as compared to conventional assays (0.5%) and b) using a 3D imaging technique for optimal capture of NETs, which are topologically superimposed on neutrophils. In this assay, we confirmed low levels of NET release upon human ICx stimulation which were positive for citrullinated histones and neutrophil elastase. In contrast to PMA-induced NET release, ICx-induced NET release was unchanged when co-incubated with diphenyleneiodonium (DPI). We were able to quantify NET release upon stimulation with serum from RA and SLE patients, which was not observed with normal human serum. To our knowledge, this is the first semi-automated assay capable of sensitive detection and quantification of NET release at a low threshold by using 3D CLSM. The assay is applicable in a high-throughput manner and allows the in vitro analysis of NET release in ICx-mediated autoimmune diseases.

  11. Rho-kinase regulates adhesive and mechanical mechanisms of pulmonary recruitment of neutrophils in abdominal sepsis.

    Science.gov (United States)

    Palani, Karzan; Rahman, Milladur; Hasan, Zirak; Zhang, Su; Qi, Zhongquan; Jeppsson, Bengt; Thorlacius, Henrik

    2012-05-05

    We hypothesized that Rho-kinase signaling plays a role in mechanical and adhesive mechanisms of neutrophil accumulation in lung. Male C57BL/6 mice were treated with the Rho-kinase inhibitor Y-27632 prior to cecal ligation and puncture (CLP). Lung levels of myeloperoxidase (MPO) and histological tissue damage were determined 6h and 24h after CLP. Expression of Mac-1 and F-actin formation in neutrophils were quantified by using flow cytometry 6h after CLP. Mac-1 expression and F-actin formation were also determined in isolated neutrophils up to 3h after stimulation with CXCL2. Labeled and activated neutrophils co-incubated with Y-27632, an anti-Mac-1 antibody and cytochalasin B were adoptively transferred to CLP mice. Y-27632 reduced the CLP-induced pulmonary injury and MPO activity as well as Mac-1 on neutrophils. Neutrophil F-actin formation peaked at 6h and returned to baseline levels 24h after CLP induction. Rho-kinase inhibition decreased CLP-provoked F-actin formation in neutrophils. CXCL2 rapidly increased Mac-1 expression and F-actin formation in neutrophils. Co-incubation with Y-27632 abolished CXCL2-induced Mac-1 up-regulation and formation of F-actin in neutrophils. Notably, co-incubation with cytochalasin B inhibited formation of F-actin but did not reduce Mac-1 expression on activated neutrophils. Adoptive transfer experiments revealed that co-incubation of neutrophils with the anti-Mac-1 antibody or cytochalasin B significantly decreased pulmonary accumulation of neutrophils in septic mice. Our data show that targeting Rho-kinase effectively reduces neutrophil recruitment and tissue damage in abdominal sepsis. Moreover, these findings demonstrate that Rho-kinase-dependent neutrophil accumulation in septic lung injury is regulated by both adhesive and mechanical mechanisms.

  12. FRET Imaging Trackable Long-Circulating Biodegradable Nanomedicines for Ovarian Cancer Therapy

    Science.gov (United States)

    2014-09-01

    Award Number: W81XWH-13-1-0160 TITLE: FRET Imaging Trackable Long-Circulating Biodegradable ...TITLE AND SUBTITLE FRET Imaging Trackable Long-Circulating Biodegradable Nanomedicines for Ovarian Cancer Therapy 5a. CONTRACT NUMBER...strategy, which permits visualizing the biodegradation of copolymer-drug conjugates at the body, tissue and cell levels in real time. The information

  13. Binding of human serum albumin to single-walled carbon nanotubes activated neutrophils to increase production of hypochlorous acid, the oxidant capable of degrading nanotubes.

    Science.gov (United States)

    Lu, Naihao; Li, Jiayu; Tian, Rong; Peng, Yi-Yuan

    2014-06-16

    Previous studies have shown that carboxylated single-walled carbon nanotubes (SWCNTs) can be catalytically biodegraded by hypochlorite (OCl-) and reactive radical intermediates of the human neutrophil enzyme myeloperoxidase (MPO). However, the importance of protein-SWCNT interactions in the biodegradation of SWCNTs was not stressed. Here, we used both experimental and theoretical approaches to investigate the interactions of SWCNTs with human serum albumin (HSA, one of the most abundant proteins in blood circulation) and found that the binding was involved in the electrostatic interactions of positively charged Arg residues of HSA with the carboxyls on the nanotubes, along with the π-π stacking interactions between SWCNTs and aromatic Tyr residues in HSA. Compared with SWCNTs, the binding of HSA could result in a reduced effect for OCl- (or the human MPO system)-induced SWCNTs degradation in vitro. However, the HSA-SWCNT interactions would enhance cellular uptake of nanotubes and stimulate MPO release and OCl- generation in neutrophils, thereby creating the conditions favorable for the degradation of the nanotubes. Upon zymosan stimulation, both SWCNTs and HSA-SWCNTs were significantly biodegraded in neutrophils, and the degree of biodegradation was more for HSA-SWCNTs under these relevant in vivo conditions. Our findings suggest that the binding of HSA may be an important determinant for MPO-mediated SWCNT biodegradation in human inflammatory cells and therefore shed light on the biomedical and biotechnological applications of safe carbon nanotubes by comprehensive preconsideration of their interactions with human serum proteins.

  14. Inhibition of pre-B cell colony-enhancing factor (PBEF/NAMPT/visfatin) decreases the ability of human neutrophils to generate reactive oxidants but does not impair bacterial killing.

    Science.gov (United States)

    Roberts, Kate J; Cross, Andrew; Vasiev