bluuebunny/crossref_metadata_2025_split huggingface dataset:
Macrophage and interleukin-1 induced nitric oxide production and cytostasis in hamster tumor cells varying in malignant potential
Authors: Lavnikova Natasha , Burdelya Ludmila , Lakhotia Anand , Patel Naimish , Prokhorova Svetlana , Laskin Debra L 
Published: January 2018

Abstract
Nitric oxide has been shown to contribute to cytotoxicity in mouse and rat tumor cells. In these studies we examined the role of nitric oxide in cytostasis in hamster tumor cells varying in their malignant potential. Spontaneously transformed hamster embryonic fibroblasts (STHE cells) with low metastatic activity produced significantly greater amounts of nitric oxide in response to interleukin-1 (IL-1) or lipopolysaccharide (LPS) -activated hamster alveolar macrophages (HAM) than did tumor cell lines with high experimental metastatic activity (HET-SR, HET-SR1, STHE-83/20 cells). HET-SR cells, which exhibit low spontaneous metastastic activity, also produced relatively high levels of nitric oxide in response to IL-1, whereas the response of the spontaneously metastatic lines, HET-SR1 and STHE-83/20 cells, was low. IL-1 and HAM also induced cytostasis in nitric oxide-producing STHE and HET-SR cells. However, the nitric oxide synthase inhibitor, NG-monomethyl-l-arginine (l-NMMA), had no effect on this activity. These findings, together with the observation that anti-tumor necrosis factor α antibody prevented HAM-mediated cytostasis in all of the tumor cell lines demonstrate that nitric oxide is not involved in hamster macrophage-induced tumor cell growth suppression. In contrast to HAM, rat alveolar macrophages, which produced nitric oxide in response to LPS, exerted similar levels of cytostasis toward all of the hamster tumor cell variants, an action that was blocked by l-NMMA in HETSR, HET-SR1, and STHE-83/20 cells. Thus production of nitric oxide by hamster tumor cells is inversely correlated with their malignant potential. However, nitric oxide does not appear to be involved in IL-1-or HAM-mediated cytostasis toward hamster tumor cells.
Characterization of clonally derived, spontaneously transformed bone marrow macrophage cell lines from lipopolysaccharide hyporesponsive LPS(d) and normal LPS(n) mice
Authors: Monner David A , Denker Brigitte 
Published: January 2018

Abstract
Six macrophage cell lines, each derived from a bone marrow macrophage colony grown in soft agar, were established by expansion of the macrophage clones in liquid culture until spontaneous transformation occurred. Four lines originated from the LPS(d) nonresponder mouse strain C3H/HeJ and two from the LPS(n) responder strain CBA/J. The cell lines adhered to plastic and glass surfaces and displayed typical macrophage functions such as phagocytosis and nonspecific esterase activity. Flow cytometry analyses showed that the lines expressed the macrophage surface markers CD11b, CD13, CD32/16, F4/80, and BM8 constitutively. A moderate expression of the adhesion receptor CD11a, but only a very low expression of its ligand CD54, was observed. A minor fraction of the cells in each line constitutively expressed MHC class II antigen, and its expression could be up-regulated in each cell line by treatment with interferon-γ (IFN-γ). Secretion of the inflammatory mediators nitric oxide (NO), interleukin-6 (IL-6), and tumor necrosis factor α (TNF-α) after induction by three bacterial derivatives, heat-killed Salmonella typhimurium (HKS), lipopolysaccharide (LPS), and the Mycoplasma fermentans-derived amphiphilic lipid MDHM, were examined in detail. Not only did the lines differ in the amounts of mediators secreted in response to any one stimulus, but the doses of MDHM or LPS required for 50% maximal induction of NO varied up to 10-fold among the four LPS(d) cell lines, suggesting considerable functional heterogeneity between the clones. Secretion of large amounts of TNF-α was induced in all the cell lines by HKS. Although it could be shown that exogenously added TNF-α acted synergistically with IFN-γ to induce NO release from the cell lines, an autocrine role for TNF-α during HKS-IFN-γ induction of NO synthesis could not be substantiated. Neutralization of TNF-α with a specific antibody completely blocked NO induction by exogenous TNF-α but did not abrogate NO release either by HKS-IFN-γ-induced cells or by macrophages treated with supernatant from an HKS-IFN-γ-activated cell line. These results indicate that the clones are arrested in distinct stages of differentiation and retain some properties of normal untransformed macrophages. They should be helpful tools for investigations into macrophage function.
Secretory leukocyte proteinase inhibitor is a major leukocyte elastase inhibitor in human neutrophils
Authors: Sallenave Jean-Michel , Si-Ta har Mustapha , Cox Gerard , Chignard Michel , Gauldie Jack 
Published: January 2018

Abstract
Secretory leukocyte proteinase inhibitor (SLPI) is the main neutrophil elastase (HLE) inhibitor found in the upper airways during pulmonary inflammation. It has been shown to be synthesized and secreted in vitro by epithelial cells and has been localized in tracheal glands and bronchiolar epithelial cells by immunocytochemistry. In this study, using immunodetection and immunopurification techniques with specific anti-SLPI immunoglobulin G (IgG), we show that SLPI is present as a native 14-kDa molecule in neutrophil cytosol. In addition, we demonstrate that SLPI is the major inhibitor of HLE present in neutrophil cytosol because pre-incubation with specific anti-SLPI IgG was able to inhibit completely the anti-HLE activity of the cytosol. SLPI can be secreted (probably in an inactive form) by neutrophils and its secretion is enhanced when the cells are stimulated with phorbol myristate acetate (PMA). Elafin, an elastase-specific inhibitor, is also present in minute amounts in neutrophil cytosol and its secretion can be upregulated. The presence of SLPI in the cytosol of neutrophils may serve as a protective screen against proteinases spilling from azurophilic granules. An alternative or supplementary role may be the maintenance of a differentiated phenotype.
Complex regulation of human neutrophil activation by actin filaments: dihydrocytochalasin B and botulinum C2 toxin uncover the existence of multiple cation entry pathways
Authors: Wenzel-Seifert Katharina , Lentzen Hans , Aktories Klaus , Seifert Roland 
Published: January 2018

Abstract
In human neutrophils, the chemotactic peptide, N-formyl-L-methionyl-L-leucyl-L-phenalalanine (fMLP), the Ca2+-ATPase inhibitor, thapsigargin, and the lectins, concanavalin A (Con A) and mistletoe lectin I (ML I), stimulate the entry of Ca2+ and Na+ with subsequent activation of exocytosis and superoxide anion (O2–) formation. We studied the role of actin in neutrophil activation. The actin filament-disrupting substances, dihydrocytochalasin B (dhCB) and botulinum C2 toxin (C2 toxin) potentiated fMLP- and lectin-stimulated Ca2+- and Na+ entry. Lectin-induced Mn2+ entry was enhanced by actin disruption, whereas fMLP-triggered Mn2+ entry was unaffected. dhCB and C2 toxin inhibited fMLP- and lectin-stimulated Ba2+ influx. The actin disrupters also inhibited fMLP- and ML I-induced Sr2+ influx, whereas Con A-stimulated Sr2+ entry was not influenced by dhCB and C2 toxin. Thapsigargin-stimulated cation entry was not altered by actin disruption. DhCB and botulinum C2 toxin potentiated lysozyme release induced by all four stimuli. Con A and ML I per se activated O2 – formation only in the presence and not in the absence of dhCB. Con A potentiated the stimulatory effects of ML I on O2 – formation in the presence of dhCB and primed neutrophils to respond to ML I in the absence of dhCB. Our data indicate the following: (1) dhCB and C2 toxin uncover the existence of multiple cation entry pathways in neutrophils; (2) actin disruption facilitates exocytosis and O2 – formation by enhancement of Ca2+- and Na+ entry and by altering the function of proteins involved in activation of secretion and O2 – formation; and (3) Con A and ML I, which possess different sugar specificities, activate different signaling pathways in neutrophils.
Quantitation of surface CD14 on human monocytes and neutrophils
Authors: Antal-Szalmas Peter , van Strijp Jos A G , Weersink Annemarie J L , Verhoef Jan , van Kessel Kok P M 
Published: January 2018

Abstract
The absolute number of membrane-expressed CD14, the most important endotoxin receptor, on human monocytes and neutrophils shows remarkable variation in the literature. To quantify these numbers two fluorescence methods using fluorescein isothiocyanate (FITC)-labeled monoclonal antibodies (mAb) were applied. A commercially available set of standard beads was used in flow cytometry to quantitate CD14 with eight different mAbs. Independent from their isotype the various mAbs showed minor differences and indicated that peripheral blood monocytes expressed 99,500–134,600 (115,400 ± 10,600) and neutrophils 1,900–4,400 (3,300 ± 800) CD14 receptors. There was no significant difference in CD14 expression on leukocytes in unprocessed freshly obtained whole blood and after a Ficoll isolation procedure. However, a short temperature shift resulted in a 1.3- to 1.6-fold upregulation of CD14. The results obtained with the reference beads were verified with fluorescence Scatchard analysis and spectrofluorometry using mAb 26ic-FITC and showed 109,500 CD14 per monocyte and 6,700 CD14 per neutrophil. For comparison the number of CD14 on the monocytic THP-1 cells and Fcγ-receptors on human leukocytes were determined using the reference beads and flow cytometry and gave results comparable to published data. Our data indicate that resting human monocytes express roughly 110,000 CD14 molecules on their surface using a simple fluorometric assay. Correct determination of the number of CD14 and other cell surface receptors is of importance in the monitoring of septic patients.
Desensitization of the fMLP-induced NADPH-oxidase response in human neutrophils is lacking in okadaic acid-treated cells
Authors: Harbecke Olle , Liu Li , Karlsson Anna , Dahlgren Claes 
Published: January 2018

Abstract
The chemoattractant N-formyl-methionyl-leucyl-phenylalanine (fMLP) interacts with neutrophils, generating signals that induce activation of the superoxide anion/hydrogen peroxide-producing NADPH-oxidase. Low temperature binding of fMLP to its neutrophil surface receptors is associated with a desensitization of the cells with respect to activation of the oxidase. Other stimuli can still activate the oxidase (in fact even induce a primed response), indicating that the observed phenomenon is stimulus specific and could not be accounted for by an effect on the oxidase itself. Furthermore, no desensitization is obtained in the presence of cytochalasin B, suggesting that the cytoskeleton is involved in the process leading to desensitization. Okadaic acid is a toxin produced by dinoflagellates and exerts its effects by an inhibition of cellular phosphatases. To investigate the role of phosphorylation/dephosphorylation events in the desensitization process we used okadaic acid as a scientific tool. We show that neutrophils treated with okadaic acid are primed with respect to the fMLP-induced production of superoxide anion, and that no desensitization is obtained in toxin-treated cells. Because the recovery of ligand-receptor complexes in a Triton X-100-insoluble fraction is very low in the cells treated with okadaic acid, we suggest that protein dephosphorylation is required to obtain binding to the cytoskeleton of occupied fMLP receptors; binding of the occupied receptors to the cell cytoskeleton being the mechanism behind desensitization.
Significance of macrophage tropism of SIV in the macaque model of HIV disease
Authors: Stephens Edward B , Galbreath David , Liu Zhen Qian , Sahni Manisha , Li Zhuang , Lamb-Wharton Rebecca , Foresman Larry , Joag Sanjay V , Narayan Opendra 
Published: January 2018

Abstract
Microglia, alveolar macrophages, and Langerhans cells are representatives of cells of macrophage lineage that are susceptible to infection with HIV-1 and they play important roles in the pathogenesis of AIDS dementia, lymphoid interstitial pneumonia, and systemic viral invasion from mucosal surfaces, respectively. In contrast, elimination of CD4+ T cells with resultant development of immunosuppression and AIDS is thought to be reflective of the exclusive tropism of the virus for CD4+ T cells. Examination of these concepts in macaques infected with molecularly cloned strains of SIVmac suggested that all strains of the virus are both macrophage- and lymphocyte-tropic and that all aspects of pathogenesis including loss of CD4+ T cells are dependent on infection in both cell types. However, viral clones that caused productive lytic infection in macrophages were less virulent than those which caused persistent nonproductive infection. The former caused subclinical and even immunizing infections, whereas the latter caused activation and productive infection in CD4+ T cells, AIDS, and systemic infection, even after inoculation of the virus on mucosal surfaces. If these findings on SIVmac are relevant to HIV-1 disease, then demonstration that HIV-1 isolates are macrophage-tropic probably does not necessarily correlate with their pathogenic potential.
GM-CSF and its effects on replication of HIV-1 in cells of macrophage lineage
Authors: Crowe Suzanne M , Lopez Angel 
Published: January 2018

Abstract
Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a hemopoetic growth factor that is a member of the four-helix bundle family of cytokines and growth factors. It regulates the proliferation and differentiation of granulocytes and cells of macrophage lineage from bone marrow progenitor cells, mediating these activities through binding to its receptor. Most studies examining the effects of GM-CSF on HIV-1 replication in primary monocytes and macrophages, and in related cell lines, have demonstrated augmentation of HIV-1 expression in vitro, although some reports have been at variance with these findings. These laboratory-based observations have been confirmed in limited clinical trials. This review outlines the details of these studies and considers mechanisms by which GM-CSF may exert its effects on cells of this lineage.
Intracellular GSH content and HIV replication in human macrophages
Authors: Garaci Enrico , Palamara Anna T , Ciriolo Maria R , D'Agostini Cartesio , Ab del-Latif Mohamed S , Aquaro Stefano , Lafavia Emanuela , Rotilio Giuseppe 
Published: January 2018

Abstract
In vitro HIV-1 infection induced a significant decrease in intracellular reduced glutathione (GSH) in human macrophages. Such a decrease was observed at the time of infection corresponding to maximum release of virus from infected cells and was not related to cell cytotoxicity. GSH loss was not related to its oxidation or leakage through the cell membrane. Inhibition of intracellular GSH synthesis by buthionine sulfoximine (BSO) did not further decrease GSH levels with respect to the decrease caused by HIV alone. However, treatment of macrophages with BSO significantly increased the HIV yield in the supernatant. Exogenous GSH strongly suppressed the production of p24 gag protein as well as the virus infectivity. Previous observations with other RNA and DNA viruses consistently showed that GSH antiviral effect occurred at late stages of virus replication and was related to the selective decrease of specific glycoproteins, such as gp120, which are particularly rich in disulfide bonds.
Monoclonal antibody to ICAM-1 preserves postischemic blood flow and reduces infarct size after ischemia-reperfusion in rabbit
Authors: Zhao Zhi-Qing , Lefer David J , Sato Hiroki , Hart K K , Jefforda R R , Vinten-Johansen J 
Published: January 2018

Abstract
Neutrophils are pivotal in the pathogenesis of reperfusion injury leading to myocardial infarction. Firm adhesion of PMN to endothelium may be initiated by the interaction between constitutively expressed intercellular adhesion molecule-1 (ICAM-1) on endothelium and β2 integrin (CDllb/CD18) on neutrophils. We tested the hypothesis that a monoclonal antibody (mAb RR1/1) against ICAM-1 would preserve postischemic myocardial blood flow and attenuate myocardial injury in an anesthetized rabbit model of coronary occlusion and reperfusion. Either mAb RR1/1 or isotypematched control mAb (R3.1) was injected 10 min before reperfusion. Postischemic myocardial blood flow in the area at risk (Ar) and necrotic area was significantly improved with mAb RR1/1 treatment compared with vehicle and mAb R3.1 during the reperfusion period. RR1/1 had no effect on nonischemic zone blood flow. The Ar as a percent of left ventricle was comparable between groups. Infarct size (TTC) as a percent of Ar was significantly reduced by mAb RR1/1 compared with saline vehicle and mAb R3.1. Plasma creatine kinase activity confirmed the reduction of infarct size in mAb RR1/1 group. In in vitro studies, 40 μg/mL mAb RR1/1, which approximates the plasma concentration of 2 mg/kg mAb RR1/1, markedly inhibited platelet-activating factor-stimulated neutrophil adherence to rabbit aortic endothelium. We conclude that blockade of ICAM-1 during reperfusion reduces postischemic perfusion defects and attenuates the progression of myocardial injury leading to necrosis. This cardioprotection by mAb RR1/1 may be due to inhibition of neutrophil adhesion to the coronary endothelium.
Apoptosis and in vivo distribution and clearance of eosinophils in normal and Trichinella spiralis-infected rats
Authors: Gon Songi , Saito Susumu , Takeda Yuji , Miyata Hiroaki , Takatsu Kiyoshi , Sendo Fujiro 
Published: January 2018

Abstract
We examined apoptosis of eosinophils obtained from normal rats and rats infected with Trichinella spiralis (T. spiralis). A considerable percentage of normal rats underwent apoptosis within a few hours, however, the apoptosis rate of infected rats was significantly lower. This rate began decreasing only 12 h after infection, reached its lowest level on day 3, and was restored to normal by day 40. We also studied the effects on eosinophil apoptosis of culture supernatants from Concanavalin A-stimulated spleen cells from infected rats and found that supernatants from days 3, 7, and 18 of infection inhibited apoptosis eosinophils from normal rats. We then examined the distribution and clearance of eosinophils in vivo. In normal rats, the largest numbers of eosinophils were found in the spleen, liver, and bone marrow. In the infected rats, however, by day 3, by which time the worms had begun to migrate, there was a striking increase in these cells in the intestines. In summary, normal eosinophils are unexpectedly sensitive to apoptosis, whereas infected eosinophils become resistant to this form of cell death.
Modulation of nitric oxide production in RAW 264.7 cells by transforming growth factor-beta and interleukin-10: differential effects on free and encapsulated immunomodulator
Authors: Seyler Isabelle , Appel Martine , Devissaguet Jean-Philippe , Legrand Philippe , Barratt Gillian 
Published: January 2018

Abstract
The mouse macrophage cell line RAW 264.7 can be stimulated to produce nitric oxide (NO) by muramyltripeptide cholesterol included within biodegradable poly(D,L-lactide) nanocapsules (NC MTP-Chol). The aim of this work was to determine whether one or both of the cytokines transforming growth factor-beta (TGF-β) and interleukin-10 (IL-10) could be responsible for feedback control seen at high concentrations. Activated RAW 264.7 cells produced TGF-β1. When exogenous TGF-β1 was added during stimulation, a dose-dependent inhibition of NO production was observed when NC MTP-Chol was used, whereas activation by the soluble muramyl dipeptide (MDP) was not affected. Furthermore, addition of a blocking antibody to TGF-β arrested the fall in NO production seen at high concentrations of NC MTP-Chol. Addition of IL-10 during RAW 264.7 cell activation also reduced NO production; however, in this case, both NC MTP-Chol and MDP were equally affected. The presence of anti-IL-10 antibody during activation significantly increased NO production.
Effect of alterations of blood cholesterol levels on macrophages in the myocardium of New Zealand White rabbits
Authors: Kinscherf Ralf , Kamencic Huse , Deigner Hans-Peter , Pill Johannes , Schmiedt Walther , Schrader Michael , Metz Jurgen 
Published: January 2018

Abstract
We investigated the effect of alterations of blood cholesterol levels on macrophages (mΦ) in the myocardium of New Zealand White (NZW) rabbits. Three groups of NZW rabbits were used: controls, rabbits fed a 0.5% cholesterol-enriched diet (CH-D) for 96 days, and rabbits fed a 0.5% CH-D for 96 days followed by normal chow for 4 months. Immunohistochemical analysis by mAbs directed against mΦ (RAM-11) and Mn superoxide dismutase (MnSOD) were quantified by computer-assisted morphometry. Using cultured human and rabbit mΦ, a cross-reaction of the human MnSOD mAbs was found as well as the predominant localization of MnSOD-immunoreactivity (IR) in mitochondria, In group 1, only a very few RAM-11-immunoreactive (ir) mΦ occurred in the interstitial space of the myocardium. In group II blood cholesterol levels significantly increased in parallel with the numbers of mΦ, which often contained lipid droplets (foam cells). Although blood cholesterol concentrations regressed about 10-fold in group III, mΦ in the myocardium were found to be reduced only about 20%. Most mΦ were also MnSOD-ir. In atherosclerotic coronary arteries RAM-11-IR was located in mΦ and also extracellularly, whereas MnSOD-IR was found only in mΦ. Drastically induced MnSOD in the mitochondria of mΦ is suggested as an indicator of increased oxidative stress caused by in vitro conditions or by phagocytosis of low-density lipoprotein in vivo. Elevation of the cholesterol level leads to a long-term increase and its regression results in a delayed reduction of such mΦ, which seem to play a key role in the atherogenesis of the coronary arteries as well.
Effects of acute ethanol exposure on cellular immune responses in a murine model of thermal injury
Authors: Faunce Douglas E , Gregory Meredith S , Kovacs Elizabeth J 
Published: January 2018

Abstract
To test the effects of acute ethanol exposure on immune function after thermal injury, mice with blood alcohol levels of 100 mg/dL were given a 15% total body surface area dorsal scald or sham injury. Bacterial challenge resulted in 100 and 40% mortality in burn + ethanol- and burn + vehicle-treated mice, respectively. Delayed-type hypersensitivity responses were also significantly suppressed in burn + ethanol-treated mice. At 1 and 4 days post-burn, concanavalin A (ConA) -induced total splenocyte proliferation in burn + ethanol-treated groups was significantly decreased (P &lt; 0.01) compared with burn + vehicle- or sham-treated animals. This decrease was not observed in total splenocytes cultured with anti-CD3ε or among adherence-depleted splenocytes given ConA or anti-CD3ε. FACS analyses revealed no changes in splenocyte sub-type ratios in burn + ethanol mice. The data herein demonstrate that acute ethanol exposure before thermal injury results in enhanced susceptibility to bacterial infection and markedly suppressed cellular immunity, which appears to be macrophage dependent.