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Neutrophil Peptides (neutrophil + peptide)

Distribution by Scientific Domains
Medical Sciences55%
Chemistry44%

Kinds of Neutrophil Peptides

  • human neutrophil peptide
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    Selected Abstracts

    iTRAQ-coupled two-dimensional liquid chromatography/tandem mass spectrometric analysis of protein profile in Escherichia coli incubated with human neutrophil peptide 1 , potential in antimicrobial strategy

    RAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 18 2010
    Yu Si Zhou
    First page of article [source]

    Cathelicidin LL-37 induces the generation of reactive oxygen species and release of human ,-defensins from neutrophils

    BRITISH JOURNAL OF DERMATOLOGY, Issue 6 2007
    Y. Zheng
    Summary Background, Psoriasis is characterized by epidermal infiltration of neutrophils that destroy invading microorganisms via a potent antimicrobial arsenal of oxidants and antimicrobial agents. In contrast to atopic dermatitis, psoriasis exhibits low levels of skin infections due to the presence of antimicrobial agents, including cathelicidin LL-37. LL-37 kills a broad spectrum of microbes, and activates neutrophil chemotaxis. Objective, To determine whether or not LL-37 could regulate additional neutrophil functions such as production of cytokines/chemokines, reactive oxygen species and release of neutrophil antimicrobial peptides. Methods, Human peripheral blood neutrophils were used in this study. The production of interleukin (IL)-8 and release of ,-defensins were analysed by enzyme-linked immunosorbent assay, and real-time polymerase chain reaction (PCR) was used to quantify ,-defensin gene expression. Phosphorylation of mitogen-activated protein kinase (MAPK) was determined by Western blotting. The generation of reactive oxygen species was examined using flow cytometry, and intracellular Ca2+ mobilization was measured using a calcium assay kit. Results, LL-37 enhanced the production of IL-8 under the control of MAPK p38 and extracellular signal regulated kinase (ERK), as evidenced by the inhibitory effects of p38 and ERK1/2 inhibitors on LL-37-mediated IL-8 production. Furthermore, LL-37 induced phosphorylation of p38 and ERK. We also revealed that LL-37 stimulated the generation of reactive oxygen species dose- and time-dependently, most probably via NADPH oxidase activation and intracellular Ca2+ mobilization. Finally, LL-37 induced both mRNA expression and protein release of ,-defensins, known as human neutrophil peptide 1,3. Conclusion, Taken together, we suggest that in addition to its microbicidal properties, LL-37 may contribute to innate immunity by enhancing neutrophil host defence functions at inflammation and/or infection sites. [source]

    Staphylokinase reduces plasmin formation by endogenous plasminogen activators

    EUROPEAN JOURNAL OF HAEMATOLOGY, Issue 1 2008
    Tao Jin
    Abstract Hyperfibrinolysis is a consequence of imbalance between fibrinolytic activators and their inhibitors. Increased levels of circulating plasminogen (Plg) activators such as tissue- or urokinase-type plasminogen activators (tPA or uPA respectively) are the most common causes of hyperfibrinolysis, occasionally causing major hemorrhages. We found that staphylokinase (SAK), a well-known Plg activator of bacterial origin, inhibits Plg activation mediated by endogenous tPA and uPA. Furthermore, mixture of SAK with tPA led to a significantly reduced Plg-dependent fibrinolysis. This inhibitory effect was exerted through direct action of SAK on Plg rather than indirectly on tPA or uPA. Inhibition of Plg activation by SAK is readily abrogated by interaction of SAK with human neutrophil peptides (HNPs). Finally, we show that NH2 -terminal residues of SAK are important for the inhibitory effect of SAK on tPA- and uPA-mediated Plg activation. In conclusion, SAK reduces tPA/uPA-mediated Plg activation by means of SAK.Plg complex formation, consequently downregulating tPA/uPA-induced fibrinolysis. [source]

    Human neutrophil peptides 1,3 are useful biomarkers in patients with active ulcerative colitis

    INFLAMMATORY BOWEL DISEASES, Issue 6 2009
    Shuji Kanmura MD
    Abstract Background: A specific useful biomarker for diagnosing ulcerative colitis (UC) has not yet been described. This study employed proteomics to identify serum protein biomarkers for UC. Methods: Ninety-four blood samples were isolated from patients and controls (including 48 UC, 22 Crohn's disease [CD], 5 colorectal cancer, and 6 infectious colitis patients and 13 healthy subjects). Serum samples were analyzed using the SELDI-TOF/MS ProteinChip system. After applying the samples to ProteinChip arrays, we assessed differences in the proteomes using Ciphergen ProteinChip software and identified candidate proteins, which were then characterized in immunoassays. Results: Preliminary analysis using the ProteinChip system revealed significant peak-intensity differences for 27 serum proteins between 11 patients with UC and 7 healthy subjects. Among these proteins, 3 proteins (with mass/charge ratios of approximately 3400) were identified as human neutrophil peptides 1,3 (HNP 1,3). The presence of HNP 1,3 in the patient sera was confirmed using immunoassays. Enzyme-linked immunosorbent assays demonstrated that the mean plasma concentration of HNP 1,3 was significantly higher in patients with active UC (n = 28) than in patients whose UC was in remission (n = 20) or patients with CD (n = 22), infectious colitis, or healthy subjects, and tended to be higher than in patients with colon cancer. In addition, the plasma concentration of HNP 1,3 in patients that responded to corticosteroids-based therapy decreased after treatment, whereas it was not changed in nonresponders. Conclusions: HNP 1,3 is a novel biomarker that may be useful for diagnosing patients with active UC and predicting treatment outcomes. (Inflamm Bowel Dis 2008) [source]

    Proteomic identification of human neutrophil alpha-defensins in chronic lung allograft rejection

    PROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 6 2005
    Gary L. Nelsestuen
    Abstract Chronic allograft rejection remains a leading cause of morbidity and mortality in lung transplant recipients. Currently, diagnosis is based on lung biopsies or the presence of bronchiolitis obliterans syndrome (BOS). To identify a biomarker of rejection we performed a proteome survey of archived bronchoalveolar lavage fluid (BALF) acquired from lung transplant recipients between 1993 and 1996 using mass spectrometry (MS). A total of 126 BALF samples from 57 individuals were tested. Initial MS assessment revealed numerous differences in a majority of individuals who experienced BOS, but three unusually intense peaks at m/z,=,3373, 3444, and 3488. These were identified as human neutrophil peptides 1,3 (HNP). Quantification by enzyme-linked immunoabsorbent assay showed an elevated HNP level (>0.3,ng/µg protein) in 89% of patients who developed BOS2,3 within 15,months, reaching as high as 6% of the total BALF protein. In control patients, 35% demonstrated a slightly elevated HNP level that declined in all who had subsequent BALF available for testing. HNP levels did not correlate with episodes of acute rejection, cytomegalovirus or fungal infection. In conclusion, elevated HNP levels are associated with the onset of BOS and can predate the clinical onset of disease up to 15,months. [source]

    Study of human neutrophil peptides in saliva by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry

    RAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 19 2009
    Ming-Hui Yang
    Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry is used to rapidly characterize the human neutrophil peptides , HNP 1, 2, and 3 , in saliva. The saliva excreted from the parotid and sublingual/submandibular glands of 70 individuals were collected and examined using MALDI-TOF. The MALDI approach requires no sample pretreatment other than mixing the saliva-absorbing material with the matrix and drying under ambient conditions. Tissue paper was the best material for collecting the saliva samples because of its strong texture and high absorbance, and sinapinic acid was the best MALDI matrix for the analysis of the HNPs. HNPs were detected in almost all the samples collected from the parotid glands, with no obvious differences among age or gender. In contrast, the distribution of the HNPs in the samples collected from the sublingual/submandibular glands was age-dependent: no HNPs were detected for those collected from individuals younger than 30, but the HNPs were present in all of the samples collected from those older than 60 years. The increased probability of detecting saliva HNPs with age suggests that HNPs may function as a biomarker for aging. Copyright © 2009 John Wiley & Sons, Ltd. [source]

    ORIGINAL ARTICLE: Female Genital Tract Secretions Inhibit Herpes Simplex Virus Infection: Correlation with Soluble Mucosal Immune Mediators and Impact of Hormonal Contraception

    AMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 2 2010
    Gail F. Shust
    Citation Shust GF, Cho S, Kim M, Madan RP, Guzman EM, Pollack M, Epstein J, Cohen HW, Keller MJ, Herold BC. Female genital tract secretions inhibit herpes simplex virus infection: correlation with soluble mucosal immune mediators and impact of hormonal contraception. Am J Reprod Immunol 2010; 63: 110,119 Problem, Female genital tract secretions inhibit herpes simplex virus (HSV) infection, however, the intra- and inter-subject variability, contribution of specific mediators, and impact of reproductive hormones have not been defined. Method of study, Cervicovaginal lavage (CVL) (n = 89) obtained from nine cyclers and seven women on hormonal contraception (HC), who completed between three and eight weekly visits, were examined for anti-herpes simplex virus activity and concentrations of mediators. Results, The CVL inhibited HSV infection by a mean value of approximately 57% during the follicular or luteal phase, but only by 36% in hormonal contraceptive users. Human neutrophil peptides 1,3 (HNP1-3) (P = 0.03), IL-8 (P = 0.003), lactoferrin (P = 0.005), lysozyme (P = 0.003), IgA (P = 0.002), and IgG (P = 0.02) correlated with antiviral activity. Intra-subject and inter-subject variability was observed, suggesting that factors other than hormones contribute to innate defense. Conclusion, Endogenous antimicrobial activity may provide a biomarker of healthy mucosal immunity and may be reduced in the setting of HC. However, larger prospective studies are needed. [source]