Displaying publications 1 - 20 of 21 in total

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  1. Ramasamy R, Maqbool M, Mohamed AL, Noah RM
    Cell Immunol, 2010;263(2):230-4.
    PMID: 20471005 DOI: 10.1016/j.cellimm.2010.04.004
    Neutrophils play a significant role in maintaining the integrity of innate immunity via their potent respiratory burst activity. However, the uncontrolled activation of respiratory burst in neutrophils also attributes to chronic diseases such as primary hypertension and atherosclerosis. In our study, we have investigated the activation of respiratory burst function of neutrophils harvested from essential hypertensive patients. In the presence of stimuli PMA and opsonized zymosan (OZ), hypertensive patients' neutrophils secrete significantly higher amount of superoxide anions compared to normotensive control. Although the magnitude of activation varies between both groups, yet the kinetics of activation is similar. When normotensive control's neutrophils were pre-treated with hypertensive serum, the cells failed to migrate toward fMLP which indicates the impairment of the migration property. In conclusion, the respiratory burst activity of neutrophils is affected by hypertension and their elevated superoxide anions production could be an aggravating factor in hypertension-related complication.
    Matched MeSH terms: Neutrophils/immunology*
  2. Hajar CGN, Zulkafli Z, Md Riffin NS, Tuan Mohammad TH, Safuan S, Nelson BR, et al.
    Transfus Apher Sci, 2020 Apr;59(2):102651.
    PMID: 31606336 DOI: 10.1016/j.transci.2019.09.004
    BACKGROUND: Human neutrophil antigens (HNAs) are implicated in several clinical disorders and their allelic variations have been reported for many populations. This new study was aimed to report the genotype and alleles frequencies of HNA-1, -3, -4 and -5 loci in Malays, Chinese and Indians in Peninsular Malaysia.

    METHODS: A total of 222 blood samples were collected from healthy, unrelated Malay, Chinese and Indian individuals. Their HNA-1, -3 and -4 and HNA-5 loci were genotyped using polymerase chain reaction-sequence specific primer (PCR-SSP) or PCR-restriction fragment length polymorphism (RFLP) assays.

    RESULTS: All HNA loci are polymorphic, except for HNA -4. Geneotypes HNA-1a/1b, -3a/3b and -4a/4a were observed most frequently at these three loci in all three ethnic groups. In contrast, HNA-5a/5b and -5a/5a were observed as the predominant genotypes in Malays vs. Chinese and Indians, respectively. The Malays, Chinese and Indians shared HNA -3a (0.505-0.527), HNA -4a (1.000) and -5a (0.676-0.854) as the most frequent alleles. However, HNA-1a was found to be the most common in Malays (0.506) and Chinese (0.504) and HNA-1b for Indians (0.525).

    CONCLUSION: Combined with HNA data that have been published for Malay subethnic and Orang Asli groups, this study provides the first fully comprehensive HNA dataset for populations to be found in Peninsular Malaysia. Overall, our findings provide further evidence of genetic complexity in the region. This now publicly available HNA dataset can be used as a reliable reference source for improving medical outcomes.

    Matched MeSH terms: Neutrophils/immunology*
  3. Chuah C, Jones MK, Burke ML, McManus DP, Owen HC, Gobert GN
    Cell. Microbiol., 2014 Nov;16(11):1666-77.
    PMID: 24898449 DOI: 10.1111/cmi.12316
    Neutrophils contribute to the pathological processes of a number of inflammatory disorders, including rheumatoid arthritis, sepsis and cystic fibrosis. Neutrophils also play prominent roles in schistosomiasis japonica liver fibrosis, being central mediators of inflammation following granuloma formation. In this study, we investigated the interaction between Schistosoma japonicum eggs and neutrophils, and the effect of eggs on the inflammatory phenotype of neutrophils. Our results showed significant upregulated expression of pro-inflammatory cytokines (IL-1α, IL-1β and IL-8) and chemokines (CCL3, CCL4 and CXCL2) in neutrophils after 4 h in vitro stimulation with S. japonicum eggs. Furthermore, mitochondrial DNA was released by stimulated neutrophils, and induced the production of matrix metalloproteinase 9 (MMP-9), a protease involved in inflammation and associated tissue destruction. We also found that intact live eggs and isolated soluble egg antigen (SEA) triggered the release of neutrophil extracellular traps (NETs), but, unlike those reported in bacterial or fungal infection, NETs did not kill schistosome eggs in vitro. Together these show that S. japonicum eggs can induce the inflammatory phenotype of neutrophils, and further our understanding of the host-parasite interplay that takes place within the in vivo microenvironment of schistosome-induced granuloma. These findings represent novel findings in a metazoan parasite, and confirm characteristics of NETs that have until now, only been observed in response to protozoan pathogens.
    Matched MeSH terms: Neutrophils/immunology*
  4. Eg KP, Thomas RJ, Masters IB, McElrea MS, Marchant JM, Chang AB
    Pediatr Pulmonol, 2020 09;55(9):2444-2451.
    PMID: 32584469 DOI: 10.1002/ppul.24924
    INTRODUCTION/AIM: A validated tool for scoring bronchitis during flexible bronchoscopy (FB) is potentially useful for clinical practice and research. We aimed to develop a bronchoscopically defined bronchitis scoring system in children (BScore) based on our pilot study.

    METHODS: Children undergoing FB were prospectively enrolled. Their FB was digitally recorded and assessed (two clinicians blinded to each other and clinical history) for six features: secretion amount (six-point scale), secretion color (BronkoTest, 0-8), mucosal oedema (0-3), ridging (0-3), erythema (0-3), and pallor (0-3) based on pre-determined criteria. We correlated (Spearman's rho) each feature with bronchoalveolar lavage (BAL) neutrophil percentage (neutrophil%). BScore was then derived using models with combinations of the six features that best related to airway BAL neutrophil%. The various models of BScore were plotted against BAL neutrophil% using receiver operating characteristic (ROC) curves.

    RESULTS: We analyzed 142 out of 150 children enrolled. Eight children were excluded for unavailability of BAL cytology or FB recordings. Chronic/recurrent cough was the commonest indication for FB (75%). The median age was 3 years (IQR, 1.5-5.3 years). Secretion amount (r = 0.42) and color (r = 0.46), mucosal oedema (r = 0.42), and erythema (r = 0.30) significantly correlated with BAL neutrophil%, P 10%).

    CONCLUSION: This prospective study has developed the first validated bronchitis scoring tool in children based on bronchoscopic visual inspection of airways. Further validation in other cohorts is however required.

    Matched MeSH terms: Neutrophils/immunology*
  5. Ghazalee NS, Jantan I, Arshad L, Haque MA
    Phytother Res, 2019 Apr;33(4):929-938.
    PMID: 30618097 DOI: 10.1002/ptr.6285
    Zingiber zerumbet rhizome has been used in traditional medicine mainly for the treatment of various immune-inflammatory related ailments and has been shown to exhibit a wide spectrum of biological effects especially antioxidant and anti-inflammatory activities. The present study was aimed to investigate the immunosuppressive effects of the standardized 80% ethanol extract of Z. zerumbet at 100, 200, and 400 mg/kg on the innate immune responses in male Wistar rats. The immune parameters determined were chemotaxis of neutrophils, Mac-1 expression, engulfment of Escherichia coli by neutrophils, reactive oxygen species production, and plasma lysozyme and ceruloplasmin levels. Zerumbone was qualitatively and quantitatively determined in the extract by using a validated reversed-phase HPLC, whereas liquid chromatography tandem-mass spectrometry (LC -MS/MS) was used to profile the secondary metabolites. Z. zerumbet significantly inhibited the migration of neutrophils, expressions of CD11b/CD18 integrin, phagocytic activity, and production of reactive oxygen species in a dose-dependent manner. The extract also dose-dependently inhibited the expressions of lysozyme and ceruloplasmin in the rat plasma. Z. zerumbet extract possessed strong inhibitory effects on the innate immune responses and has potential to be developed into an effective immunosuppressive agent.
    Matched MeSH terms: Neutrophils/immunology
  6. Catapano M, Vergnano M, Romano M, Mahil SK, Choon SE, Burden AD, et al.
    J Invest Dermatol, 2020 04;140(4):816-826.e3.
    PMID: 31539532 DOI: 10.1016/j.jid.2019.08.444
    Psoriasis is an immune-mediated skin disorder associated with severe systemic comorbidities. Whereas IL-36 is a key disease driver, the pathogenic role of this cytokine has mainly been investigated in skin. Thus, its effects on systemic immunity and extracutaneous disease manifestations remain poorly understood. To address this issue, we investigated the consequences of excessive IL-36 activity in circulating immune cells. We initially focused our attention on generalized pustular psoriasis (GPP), a clinical variant associated with pervasive upregulation of IL-36 signaling. By undertaking blood and neutrophil RNA sequencing, we demonstrated that affected individuals display a prominent IFN-I signature, which correlates with abnormal IL-36 activity. We then validated the association between IL-36 deregulation and IFN-I over-expression in patients with severe psoriasis vulgaris (PV). We also found that the activation of IFN-I genes was associated with extracutaneous morbidity, in both GPP and PV. Finally, we undertook mechanistic experiments, demonstrating that IL-36 acts directly on plasmacytoid dendritic cells, where it potentiates toll-like receptor (TLR)-9 activation and IFN-α production. This effect was mediated by the upregulation of PLSCR1, a phospholipid scramblase mediating endosomal TLR-9 translocation. These findings identify an IL-36/ IFN-I axis contributing to extracutaneous inflammation in psoriasis.
    Matched MeSH terms: Neutrophils/immunology
  7. Chin VK, Basir R, Nordin SA, Abdullah M, Sekawi Z
    Int Microbiol, 2020 May;23(2):127-136.
    PMID: 30875033 DOI: 10.1007/s10123-019-00067-3
    Human leptospirosis is considered as one of the most widespread and potentially fatal zoonotic diseases that causes high mortality and morbidity in the endemic regions of tropical and subtropical countries. The infection can arise from direct or indirect exposure of human through contaminated environment that contains leptospires or animal reservoirs that carry leptospires. The clinical manifestations during human leptospirosis ranges from asymptomatic, mild infections to severe and life-threatening complications involving multi-organ failures with kidneys, lungs and liver severely affected. Despite much efforts have been put in to unravel the pathogenesis during human leptospirosis, it remains obscure to which extent the host factors or the pathogen itself contribute towards the pathogenesis. Host innate immunity, especially, polymorphonuclear neutrophils and complement system are involved in the first line of defense during human leptospirosis. However, pathogenic Leptospira has acquired diverse evasion strategies to evade from host immunity and establish infection in infected hosts. Hence, in this review, we focus on organs pathology during human leptospiral infection and host evasion strategies employed by Leptospira. A profound understanding on leptospiral immunity and how Leptospira subvert the immune system may provide new insights on the development of therapeutic regimens against this species in future.
    Matched MeSH terms: Neutrophils/immunology
  8. Vongsak B, Gritsanapan W, Wongkrajang Y, Jantan I
    Nat Prod Commun, 2013 Nov;8(11):1559-61.
    PMID: 24427941
    The ethanol extract of Moringa oleifera Lam. leaves and its major constituents, crypto-chlorogenic acid, quercetin 3-O-glucoside and kaempferol 3-O-glucoside, were investigated on the respiratory burst of human whole blood and isolated human polymorphonuclear leukocytes (PMNs) using a luminol-based chemiluminescence assay. The chemotactic migration of PMNs was also investigated using the Boyden chamber technique. The ethanol extract demonstrated inhibitory activities on the oxidative burst and the chemotactic migration of PMNs. Quercetin 3-O-glucoside, crypto-chlorogenic acid, and kaempferol 3-O-glucoside, isolated from the extract, expressed relatively strong inhibitory activity on the oxidative burst of PMNs with IC50 values of 4.1, 6.7 and 7.0 microM, respectively, comparable with that of aspirin. They also demonstrated strong inhibition of chemotatic migration of PMNs with IC50 values of 9.5, 15.9 and 18.2 microM, respectively. The results suggest that M. oleifera leaves could modulate the immune response of human phagocytes, linking to its ethnopharmacological use as an anti-inflammatory agent. The immunomodulating activity of the plant was mainly due to its major components.
    Matched MeSH terms: Neutrophils/immunology
  9. Wijayahadi N, Haron MR, Stanslas J, Yusuf Z
    J Chemother, 2007 Dec;19(6):716-23.
    PMID: 18230556
    Anthracyclines are the most widely used anticancer agents for breast cancer, of which doxorubicin and epirubicin have been reported to have equal efficacy. Unfortunately, the integrity of the immune system of breast cancer patients is severely affected by chemotherapy. This study compared the effect of combination chemotherapy with epirubicin (5-fluorouracil, epirubicin, cyclophosphamide (FEC)) and doxorubicin (5-fluorouracil, doxorubicin, cyclophosphamide (FDC)) regimens on subsets of the immune cells of patients with primary malignant breast tumors. Our aim was to determine the best regimen that produces the least degree of myelosuppression. Blood from 80 breast cancer patients undergoing chemotherapy (40 FEC and 40 FDC) was taken before chemotherapy and after every cycle (3 weeks) for 6 cycles. Blood was also taken from 40 normal healthy donors who served as normal control. Subsets of lymphocytes T-helper cells (CD3(+)CD4(+)), T-cytotoxic cells (CD3(+) CD8(+)), B-cells (CD19(+) CD20(+)) and NK cells (CD16(+)/CD56(+)CD3(-)) were analyzed by flow cytometry (FacsCalibur, BD) using monoclonal antibodies (Multitest, BD). All patients in the FEC and FDC groups suffered from myelosuppressive side effects. Both regimens led to an increase in the counts of monocytes but decreased polymorphonuclear cells (PMNs) and lymphocytes. Percentages of T-cytotoxic cells and NK cells were increased, but the percentage of B-cells was dramatically decreased. The phagocytic and intracellular killing ability of PMNs were also suppressed (p<0.01). No significant difference was found between the epirubicin-based regimen and doxorubicin-based regimen with regard to numbers of immune cells, percentages of lymphocytes subsets, Th/CTL ratio, engulfment and killing abilities of PMNs. In conclusion, we found that the epirubicin-based regimen is not superior to the doxorubicin-based regimen with respect to their toxicity of the immune cells, Th/CTL ratio and PMN count and functions. Moreover, both FEC and FDC regimens appear to conserve the cell-mediated immunity response needed for fighting against cancer cells.
    Matched MeSH terms: Neutrophils/immunology
  10. Chellappan DK, Yee LW, Xuan KY, Kunalan K, Rou LC, Jean LS, et al.
    Drug Dev Res, 2020 06;81(4):419-436.
    PMID: 32048757 DOI: 10.1002/ddr.21648
    Neutrophils are essential effector cells of immune system for clearing the extracellular pathogens during inflammation and immune reactions. Neutrophils play a major role in chronic respiratory diseases. In respiratory diseases such as asthma, chronic obstructive pulmonary disease, cystic fibrosis, lung cancer and others, there occurs extreme infiltration and activation of neutrophils followed by a cascade of events like oxidative stress and dysregulated cellular proteins that eventually result in apoptosis and tissue damage. Dysregulation of neutrophil effector functions including delayed neutropil apoptosis, increased neutrophil extracellular traps in the pathogenesis of asthma, and chronic obstructive pulmonary disease enable neutrophils as a potential therapeutic target. Accounting to their role in pathogenesis, neutrophils present as an excellent therapeutic target for the treatment of chronic respiratory diseases. This review highlights the current status and the emerging trends in novel drug delivery systems such as nanoparticles, liposomes, microspheres, and other newer nanosystems that can target neutrophils and their molecular pathways, in the airways against infections, inflammation, and cancer. These drug delivery systems are promising in providing sustained drug delivery, reduced therapeutic dose, improved patient compliance, and reduced drug toxicity. In addition, the review also discusses emerging strategies and the future perspectives in neutrophil-based therapy.
    Matched MeSH terms: Neutrophils/immunology
  11. Ranneh Y, Akim AM, Hamid HA, Khazaai H, Mokhtarrudin N, Fadel A, et al.
    Arch Immunol Ther Exp (Warsz), 2019 Dec;67(6):385-400.
    PMID: 31278602 DOI: 10.1007/s00005-019-00553-6
    Chronic subclinical systemic inflammation has a key role in stimulating several chronic conditions associated with cardiovascular diseases, cancer, rheumatoid arthritis, diabetes, and neurodegenerative diseases. Hence, developing in vivo models of chronic subclinical systemic inflammation are essential to the study of the pathophysiology and to measure the immunomodulatory agents involved. Male Sprague-Dawley rats were subjected to intraperitoneal, intermittent injection with saline, or lipopolysaccharide (LPS) (0.5, 1, 2 mg/kg) thrice a week for 30 days. Hematological, biochemical, and inflammatory mediators were measured at different timepoints and at the end of the study. The hearts, lungs, kidneys, and livers were harvested for histological evaluation. Significant elevation in peripheral blood leukocyte includes neutrophils, monocytes, and lymphocytes, as well as the neutrophils-to-lymphocyte ratio. The pro-inflammatory mediator levels [C-reactive protein, tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-1β, and IL-8] along with the biochemical profile (alkaline phosphatase, aspartate aminotransferase, alanine aminotransferase, gamma-glutamyl transferase, creatine kinase, creatinine, and urea) were increased significantly (P 
    Matched MeSH terms: Neutrophils/immunology*
  12. Arshad L, Jantan I, Bukhari SNA, Fauzi MB
    Curr Pharm Biotechnol, 2018;19(6):468-482.
    PMID: 29968535 DOI: 10.2174/1389201019666180703092723
    BACKGROUND: 3,5-Bis[4-(diethoxymethyl)benzylidene]-1-methyl-piperidin-4-one (BBP), a novel synthetic curcumin analogue has previously been shown to manifest potent immunosuppressive effects on the in vitro phagocytosis process of human neutrophils.

    OBJECTIVE: In the present study, BBP was investigated for it's in vivo innate and adaptive immune responses mediated by different humoral and cellular immune factors.

    METHODS: Male Balb/c mice were orally fed with BBP (5, 10 and 20 mg/kg) for a period of 14 days and immunized with sheep red blood cells (sRBC) on day 0 for the determination of adaptive responses. The effects of BBP on phagocytosis process of neutrophils isolated from blood of treated/untreated animals were determined. The ceruloplasmin and lysozyme serum levels and myeloperoxidase (MPO) plasma level were also monitored. The mechanism was further explored by assessing its effects on the proliferation of T and B lymphocytes, T-lymphocytes subsets CD4+ and CD8+ and on the secretion of Th1/Th2 cytokines as well as serum immunoglobulins (IgG, IgM) and delayed type hypersensitivity (DTH) reaction.

    RESULTS: BBP showed a significant dose-dependent reduction on the migration of neutrophils, Mac-1 expression, phagocytic activity and reactive oxygen species (ROS) production. In comparison to the sensitized control group, a dose-dependent inhibition was observed on lymphocyte proliferation along with the downregulation of effector cells expression and release of cytokines. Moreover, a statistically significant decrease was perceived in serum levels of ceruloplasmin, lysozyme and immunoglobulins and MPO plasma level of BBP-treated mice. BBP also dose-dependently inhibited sheep red blood cells (sRBC)-induced swelling rate of mice paw in DTH.

    CONCLUSION: These findings suggest the potential of BBP as a potent immunosuppressive agent.

    Matched MeSH terms: Neutrophils/immunology
  13. Tan HT, Hagner S, Ruchti F, Radzikowska U, Tan G, Altunbulakli C, et al.
    Allergy, 2019 02;74(2):294-307.
    PMID: 30267575 DOI: 10.1111/all.13619
    BACKGROUND: Asthma is a chronic respiratory disease with marked clinical and pathophysiological heterogeneity. Specific pathways are thought to be involved in the pathomechanisms of different inflammatory phenotypes of asthma; however, direct in vivo comparison has not been performed.

    METHODS: We developed mouse models representing three different phenotypes of allergic airway inflammation-eosinophilic, mixed, and neutrophilic asthma via different methods of house dust mite sensitization and challenge. Transcriptomic analysis of the lungs, followed by the RT-PCR, western blot, and confocal microscopy, was performed. Primary human bronchial epithelial cells cultured in air-liquid interface were used to study the mechanisms revealed in the in vivo models.

    RESULTS: By whole-genome transcriptome profiling of the lung, we found that airway tight junction (TJ), mucin, and inflammasome-related genes are differentially expressed in these distinct phenotypes. Further analysis of proteins from these families revealed that Zo-1 and Cldn18 were downregulated in all phenotypes, while increased Cldn4 expression was characteristic for neutrophilic airway inflammation. Mucins Clca1 (Gob5) and Muc5ac were upregulated in eosinophilic and even more in neutrophilic phenotype. Increased expression of inflammasome-related molecules such as Nlrp3, Nlrc4, Casp-1, and IL-1β was characteristic for neutrophilic asthma. In addition, we showed that inflammasome/Th17/neutrophilic axis cytokine-IL-1β-may transiently impair epithelial barrier function, while IL-1β and IL-17 increase mucin expressions in primary human bronchial epithelial cells.

    CONCLUSION: Our findings suggest that differential expression of TJ, mucin, and inflammasome-related molecules in distinct inflammatory phenotypes of asthma may be linked to pathophysiology and might reflect the differences observed in the clinic.

    Matched MeSH terms: Neutrophils/immunology
  14. Yang Y, Swierczak A, Ibahim M, Paiva P, Cann L, Stevenson AW, et al.
    Radiother Oncol, 2019 04;133:93-99.
    PMID: 30935588 DOI: 10.1016/j.radonc.2019.01.006
    BACKGROUND: Synchrotron microbeam radiation therapy (MRT) is a new, evolving form of radiotherapy that has potential for clinical application. Several studies have shown in preclinical models that synchrotron MRT achieves equivalent tumor control to conventional radiotherapy (CRT) but with significantly reduced normal tissue damage.

    METHODS: To explore differences between these two modalities, we assessed the immune cell infiltrate into EMT6.5 mammary tumors after CRT and MRT.

    RESULTS: CRT induced marked increases in tumor-associated macrophages and neutrophils while there were no increases in these populations following MRT. In contrast, there were higher numbers of T cells in the MRT treated tumors. There were also increased levels of CCL2 by immunohistochemistry in tumors subjected to CRT, but not to MRT. Conversely, we found that MRT induced higher levels of pro-inflammatory genes in tumors than CRT.

    CONCLUSION: Our data are the first to demonstrate substantial differences in macrophage, neutrophil and T cell numbers in tumors following MRT versus CRT, providing support for the concept that MRT evokes a different immunomodulatory response in tumors compared to CRT.

    Matched MeSH terms: Neutrophils/immunology
  15. Yap SN, Phipps ME, Manivasagar M, Bosco JJ
    Immunol Lett, 1999 Jun 01;68(2-3):295-300.
    PMID: 10424435
    The neutrophil antigen (NA)1 and 2 is coded by two recognized allelic forms of Fc gamma receptor IIIB (FcgammaRIIIB). FcgammaRIIIb is a low affinity receptor and preferentially removes immune complexes from the circulation. Systemic lupus erythematosus (SLE) is an autoimmune and polygenic disorder characterized by accumulation of autoimmune complexes. The majority of SLE patients in our medical center are of Chinese ethnicity, followed by Malay and Indian. Recently, studies have focussed on the Fc receptors in different ethnic groups and their relation to SLE. We chose to study the gene distribution of this receptor in the Chinese and Malays population in Malaysia. We designed a polymerase chain reaction allele specific primers (PCR-ASP) method to distinguish the two allelic forms. Genomic DNA was isolated from the peripheral blood of 183 Chinese and 55 Malays SLE patients as well as 100 Chinese and 50 Malays healthy controls. Genotyping of Chinese SLE patients revealed that the gene frequencies for FcgammaRIIIB-NA1 and FcgammaRIIIB-NA2 were 0.648 and 0.347, while in the ethnically matched healthy controls they were 0.68 and 0.32, respectively. One out of the 183 Chinese SLE patients was identified as a NA-null due to the absence of PCR product for both alleles. The FcgammaRIIIB-NA1 and FcgammaRIIIB-NA2 allele frequencies for both the Malays SLE and healthy controls were 0.62 and 0.38.
    Matched MeSH terms: Neutrophils/immunology
  16. Abbas A, Nazir H, Naseer MM, Bolte M, Hussain S, Hafeez N, et al.
    PMID: 24177882 DOI: 10.1016/j.saa.2013.10.023
    A series of new pyrazoline derivatives (1b-4c) bearing N-acyl arms and nine to twelve carbon long alkoxy side chains was synthesized and characterized on the basis of spectroscopic data and microanalysis. The nature of self-assembly to understand the interplay of alkoxy chain crystallization and various supramolecular interactions was investigated using single crystal X-ray diffraction studies. Interesting self-assembled supramolecular structures of 1b and 4c were observed in the crystal lattice owing to various CH⋯O, H⋯H, CH⋯π, lonepair⋯π and π⋯π interactions. Further, all the synthesized compounds (1b-4c) were screened for their in vitro antifungal and anti-inflammatory activities. Compounds 2b, 3b, 2c and 3c showed significant to moderate antifungal activity against Microsporum canis whereas most of the other compounds were found inactive against all the five tested fungal strains. Good anti-inflammatory activity was observed for compounds 1b with IC50 value 331 μM compared to 273 μM for Indomethacine, a standard reference drug. The bio-activity data demonstrates the relationship between lipophilicity, solubility and bioavailability.
    Matched MeSH terms: Neutrophils/immunology
  17. Ganesh PS, Vishnupriya S, Vadivelu J, Mariappan V, Vellasamy KM, Shankar EM
    Microbiol. Immunol., 2020 Feb;64(2):87-98.
    PMID: 31769530 DOI: 10.1111/1348-0421.12762
    Burkholderia cepacia complex (Bcc) are opportunistic pathogens implicated with nosocomial infections, and high rates of morbidity and mortality, especially in individuals with cystic fibrosis (CF). B. cepacia are naturally resistant to different classes of antibiotics, and can subvert the host innate immune responses by producing quorum sensing (QS) controlled virulence factors and biofilms. It still remains a conundrum as to how exactly the bacterium survives the intracellular environment within the host cells of CF patients and immunocompromised individuals although the bacterium can invade human lung epithelial cells, neutrophils, and murine macrophages. The mechanisms associated with intracellular survival in the airway epithelial cells and the role of QS and virulence factors in B. cepacia infections in cystic fibrosis remain largely unclear. The current review focuses on understanding the role of QS-controlled virulence factors and biofilms, and provides additional impetus to understanding the potentials of QS-inhibitory strategies against B. cepacia.
    Matched MeSH terms: Neutrophils/immunology
  18. Michaudel C, Mackowiak C, Maillet I, Fauconnier L, Akdis CA, Sokolowska M, et al.
    J Allergy Clin Immunol, 2018 09;142(3):942-958.
    PMID: 29331644 DOI: 10.1016/j.jaci.2017.11.044
    BACKGROUND: IL-33 plays a critical role in regulation of tissue homeostasis, injury, and repair. Whether IL-33 regulates neutrophil recruitment and functions independently of airways hyperresponsiveness (AHR) in the setting of ozone-induced lung injury and inflammation is unclear.

    OBJECTIVE: We sought to examine the role of the IL-33/ST2 axis in lung inflammation on acute ozone exposure in mice.

    METHODS: ST2- and Il33-deficient, IL-33 citrine reporter, and C57BL/6 (wild-type) mice underwent a single ozone exposure (1 ppm for 1 hour) in all studies. Cell recruitment in lung tissue and the bronchoalveolar space, inflammatory parameters, epithelial barrier damage, and airway hyperresponsiveness (AHR) were determined.

    RESULTS: We report that a single ozone exposure causes rapid disruption of the epithelial barrier within 1 hour, followed by a second phase of respiratory barrier injury with increased neutrophil recruitment, reactive oxygen species production, AHR, and IL-33 expression in epithelial and myeloid cells in wild-type mice. In the absence of IL-33 or IL-33 receptor/ST2, epithelial cell injury with protein leak and myeloid cell recruitment and inflammation are further increased, whereas the tight junction proteins E-cadherin and zonula occludens 1 and reactive oxygen species expression in neutrophils and AHR are diminished. ST2 neutralization recapitulated the enhanced ozone-induced neutrophilic inflammation. However, myeloid cell depletion using GR-1 antibody reduced ozone-induced lung inflammation, epithelial cell injury, and protein leak, whereas administration of recombinant mouse IL-33 reduced neutrophil recruitment in Il33-deficient mice.

    CONCLUSION: Data demonstrate that ozone causes an immediate barrier injury that precedes myeloid cell-mediated inflammatory injury under the control of the IL-33/ST2 axis. Thus IL-33/ST2 signaling is critical for maintenance of intact epithelial barrier and inflammation.

    Matched MeSH terms: Neutrophils/immunology
  19. Ilangkovan M, Jantan I, Mesaik MA, Bukhari SN
    Drug Des Devel Ther, 2015;9:4917-30.
    PMID: 26347462 DOI: 10.2147/DDDT.S88189
    Phyllanthus amarus (family: Euphorbiaceae) is of immense interest due to its wide spectrum of biological activities. In the present study, the standardized 80% ethanol extract of P. amarus was investigated for its modulatory activity on various cellular immune parameters, including chemotaxis of neutrophils, engulfment of Escherichia coli by neutrophils, and Mac-1 expression, in leukocytes isolated from treated/nontreated Wistar-Kyoto rats. The detailed cell-mediated activity of P. amarus was also investigated, including analysis of the effects on T- and B-cell proliferation and CD4(+) and CD8(+) T-cell subsets in splenic mononuclear cells, and estimation of serum cytokine production by activated T-cells. The main components of the extract, phyllanthin, hypophyllanthin, corilagin, geraniin, ellagic acid, and gallic acid were identified and quantitatively analyzed in the extracts, using validated reversed-phase high-performance liquid chromatography (HPLC) methods. N-formyl-methionyl-leucyl-phenylalanine (fMLP)-induced neutrophils isolated from rats administered with the extract of P. amarus, at doses ranging from 100 to 400 mg/kg for 14 days, revealed a significant dose-dependent reduction in neutrophil migration (P<0.05). Similar patterns of inhibition were also observed in phagocytic activity and in fMLP-induced changes in expression of β2 integrin polymorphonuclear neutrophils. The results in P. amarus-treated rats also demonstrated a dose-dependent inhibition of both lipopolysaccharide-stimulated B-cell proliferation and concanavalin A-stimulated T-cell proliferation as compared with sensitized control. At a dose of 400 mg/kg (P<0.01), there was a significant decrease in the (%) expression of CD4(+) and CD8(+) in splenocytes and in serum cytokines of T helper (Th1) (IL-2 and IFN-γ) and Th2 (IL-4). In conclusion, P. amarus showed effective immunosuppressive activities in cellular immune response, by various immune regulatory mechanisms, and may be useful for improvement of immune-related disorders.
    Matched MeSH terms: Neutrophils/immunology
  20. Mawa S, Jantan I, Husain K
    Molecules, 2016 Jan 05;21(1):9.
    PMID: 26742027 DOI: 10.3390/molecules21010009
    Three new triterpenoids; namely 28,28,30-trihydroxylupeol (1); 3,21,21,26-tetrahydroxy-lanostanoic acid (2) and dehydroxybetulinic acid (3) and seven known compounds; i.e., taraxerone (4); taraxerol (5); ethyl palmitate (6); herniarin (7); stigmasterol (8); ursolic acid (9) and acetyl ursolic acid (10) were isolated from the stem of Ficus aurantiaca Griff. The structures of the compounds were established by spectroscopic techniques. The compounds were evaluated for their inhibitory effects on polymorphonuclear leukocyte (PMN) chemotaxis by using the Boyden chamber technique and on human whole blood and neutrophil reactive oxygen species (ROS) production by using a luminol-based chemiluminescence assay. Among the compounds tested, compounds 1-4, 6 and 9 exhibited strong inhibition of PMN migration towards the chemoattractant N-formyl-methionyl-leucyl-phenylalanine (fMLP) with IC50 values of 6.8; 2.8; 2.5; 4.1; 3.7 and 3.6 μM, respectively, comparable to that of the positive control ibuprofen (6.7 μM). Compounds 2-4, 6, 7 and 9 exhibited strong inhibition of ROS production of PMNs with IC50 values of 0.9; 0.9; 1.3; 1.1; 0.5 and 0.8 μM, respectively, which were lower than that of aspirin (9.4 μM). The bioactive compounds might be potential lead molecules for the development of new immunomodulatory agents to modulate the innate immune response of phagocytes.
    Matched MeSH terms: Neutrophils/immunology
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