bluuebunny/crossref_metadata_2025_split huggingface dataset:
Heterogeneity in the circulating neutrophil pool: studies on subpopulations separated by continuous flow electrophoresis
Authors: Eggleton Paul , Fisher D , Crawford Neville 
Published: January 2018

Abstract
Isolated blood neutrophils from healthy individuals have been separated by continuous flow electrophoresis (CFE) as a Gaussian-shaped profile extending over 12–15 fractions, on the basis of differences in cell surface electrical charge. The fractions were pooled into three or four subpopulations; the mean electrophoretic mobilities of the least and most electronegative cells were 0.96 and 1.22 μm/sec/V/cm, respectively. Each pool of neutrophils was analyzed for functional and biochemical differences. Expression of respiratory burst in terms of the rate of superoxide production by the least and most electronegative cells to fixed concentrations of N-formyl-methionyl-leucyl-phenylalanine (fMLP, 10−7 M) or phorbol myristate acetate (PMA, 1 μg/ml) revealed that the least electronegative cells generated superoxide anion (O2−) at approximately twice the rate of the most electronegative cells. However, when lower concentrations of fMLP were used (1–5 × 10−9 M), the most electronegative cells were most active. The least electronegative cells were also the most active in terms of phagocytosis and chemotaxis. In accordance with these differences in motile function, the basal F-actin content of the least electronegative cell pool was greater than the F-actin levels found in the most electronegative cells and remained so upon stimulation with fMLP. Such neutrophil heterogeneity as detected by CFE may be important in selective marginatum and recruitment of cells to inflammatory foci and sites of infection and may in part represent subsets of cells within the circulation that are primed in vivo to respond to inflammatory stimuli.
Mobilizable intracellular pool of p55 (type I) tumor necrosis factor receptors in human neutrophils
Authors: Porteu Françoise , Nathan Carl F 
Published: January 2018

Abstract
The distribution of type I (p55) and type II (p75) tumor necrosis factor receptors (TNF-Rs) in human polymorphonuclear neutrophils (PMNs) was analyzed by Western blotting of subcellular fractions obtained by centrifugation of PMN cavitates on Percoll density gradients. In resting PMNs, the p55 receptor was associated with both γ and β fractions, enriched in plasma membranes and specific granules, respectively, whereas the p75 TNF-R was located only in the γ fraction. Intracellular p55 TNF-R bound 125I-labeled TNF in a ligand blot assay and migrated as a diffuse band of 46–60 kd, similar to the plasma membrane receptor. Activation of PMNs with the chemattractant N-formylmethionyl-leucyl-phenylalanine (fMLP), in conditions that induced the selective release of the tertiary granule marker gelatinase, caused the shedding of most of membrane p55 TNF-R as a 28-kd soluble form but had little effect on the distribution of the receptors in β fractions. By contrast, when specific granule secretion was induced in the presence of cytochalasin B, a marked decrease in reactivity of β fractions with anti–p55 TNF-R antibody was observed. At the same time, the amount of soluble 28-kd fragment found in the supernatant was increased. Thus, the intracellular pool of p55 TNF-R is associated with functional secretory granules and is redistributed in response to PMN activation.
Phagocytosis of apoptotic neutrophils does not induce macrophage release of thromboxane B2
Authors: Meagher Laura C , Savill John S , Baker Amanda , Fuller Richard W , Haslett Christopher 
Published: January 2018

Abstract
Senescent human neutrophils undergo programmed cell death (apoptosis), leading to their recognition and phagocytosis by mature macrophages. At inflamed sites in vivo these processes may represent a neutrophil removal mechanism with the potential to limit the histotoxic capacity of these cells. Phagocytosis can provoke marked proinflammatory responses by macrophages. A macrophage proinflammatory response to the ingestion of apoptotic neutrophils would limit the efficacy of this nautrophil removal mechanism as a component of inflammatory resolution. In the present study we examined two macrophage proinflammatory responses; secretion of the granule enzyme N-acetyl-β-d-glucosaminidase (NAG) and release of the membrane lipid-derived inflammatory mediator thromboxane A2 (TxA2, measured as TxB2). By contrast with the marked release of NAG and TxB2 elicited by phagocytosis of control particles (opsonised zymosan and immunoglobulin G–coated erythrocytes), macrophage ingestion of apoptotic neutrophils resulted in minimal release of NAG and no release of TxB2; indeed, there was a small depression of TxB2 release that was not due to a toxic effect of neutrophil uptake because macrophages ingesting apoptotic neutrophils retained marked TxB2 responses to subsequent stimulation with opsonised zymosan. Furthermore, there was significant TxB2 release in response to macrophage phagocytosis of apoptotic neutrophils that had been coated with opsonic serum, demonstrating that the lack of macrophage response was determined by the mechanism of recognition rather than the properties of the apoptotic particle itself. These observations are consistent with the hypothesis that macrophage clearance of senscent neutrophils undergoing apoptosis is an injury-limiting mechanism that favors resolution rather than persistence of the inflammatory response and are consistent with observations that the waves of apoptotic cell removal seen in embryological removal and thymic involution do not trigger an inflammatory response.
Actin polymerization contributes to neutrophil chemotactic dysfunction following thermal injury
Authors: Hasslen Sharon R , Ahrenholz David H , Solem Lynn D , Nelson Robert D 
Published: January 2018

Abstract
The agent(s) and mechanism(s) responsible for suppression of neutrophil chemotaxis in association with major thermal injury have not been identified. We have proposed that the reduced random motility characterizing patients' cells may contribute to their generalized chemotactic dysfunction. Here we report that actin polymerization may be responsible for the loss of neutrophil motility associated with major thermal injury. Using a fluorescent ligand specific for polymerized or filamentous actin (NBD-phallacidin) in conjunction with flow cytometry, we have discovered that peripheral blood and exudate neutrophils from patients with major thermal injury contain increased levels of actin in a stably polymerized form. Because cyclic polymerization and depolymerization of actin is essential to cell motility, we suggest that actin polymerization may contribute in a major way to the attenuation of neutrophil random and chemotactic functions induced by major thermal injury.
Infusion of zymosan-activated plasma affects neutrophils in peripheral blood and bone marrow in sheep
Authors: Rosolia David L , McKenna Patrick J , Gee Marlys H , Albertine Kurt H 
Published: January 2018

Abstract
Intravenous infusion of zymosan-activated plasma (ZAP) in sheep results in acute lung injury mediated in part by free radical release from stimulated neutrophils that are retained in increased numbers in the pulmonary microcirculation. ZAP infusion is also associated with long-term reduction in elicited superoxide anion generation from segmented neutrophils in the circulating and bone marrow pools for at least 24 h after the infusion. The purpose of our study was to investigate the effect of ZAP infusion on leukocyte counts and neutrophil granule-associated enzyme activity in the circulating and bone marrow pools. Cytochemical methods were used to characterize enzyme activity in primary granules (acid phosphatase and myeloperoxidase) and secondary granules (alkaline phosphatase). During the infusion period, neutrophil differential counts decreased less in venous blood than in matched arterial blood. Release from bone marrow stores was evident as increased numbers of circulating band neutrophils during and after the infusion. Neutrophils in venous and arterial blood smears were degranulated acutely during and 1-3 h after the infusion was stopped. Band and segmented neutrophils in bone marrow also appeared slightly degranulated 1-2 h after the infusion. In vitro experiments showed that band and segmented neutrophils in bone marrow degranulated in response to ZAP incubation. Immature polymorphonuclear leukocytes did not degranulate. Five to 24 h after ZAP infusion, enzyme activity in circulating and bone marrow neutrophils was at baseline levels, suggesting that new cells were being released into the circulating pool because degranulated neutrophils do not synthesize new granules. Another indication of a long-term effect in bone marrow were slight decreases in the percentage of immature polymorphonuclear leukocytes and band neutrophils and a significant decrease in the percentage of eosinophils, all of which coincided with a significant increase in the percentage of segmented neutrophils. Our results demonstrate that circulating complement anaphylatoxins affect neutrophils in bone marrow as well as the vascular space.
Stimulation of human polymorphonuclear leukocytes by leukotriene B4 and platelet-activating factor: an ultrastructural and pharmacological study
Authors: Rossi Adriano G , MacIntyre D Euan , Jones Carolyn JP , McMillan Rodger M 
Published: January 2018

Abstract
Human polymorphonuclear leukocytes (PMNs) stimulated by N-formylmethionyl-leucyl- phenylalanine (fMLP), leukotriene B4 (LTB4) and platelet-activating factor (PAF) showed a similar sequence of ultrastructural changes. Exposure of unstirred PMNs to diese soluble stimuli induced a rapid (within 10 s) plasma membrane ruffling followed by polarization of cells associated with formation of broad agranular lamel, lipodia (maximal by 30 s). Similar changes were observed in stirred PMN suspensions except that the polarized cells formed multicellular aggregates with the agranular lamellipodia extending outward from the clumps. In addition, these receptor-directed agonists induced concentration-dependent PMN aggregation that was rapid and reversible, and in cells pretreated with cytochalasin B the agonists induced a degranulatory response. The calcium ionophore ionomycin also activated PMNs but, in contrast to the other stimuli, ionomycin produced irreversible aggregation and evoked enzyme release in the absence of cytochalasin B. Ionomycin stimulated LTB4 release, whereas the response induced by PAF or fMLP was barely detectable. The possible role of LTB4 and PAF in mediating responses to other agonists was investigated pharmacologically using the 5-lipoxygenase inhibitor PF 5901 and a specific PAF antagonist, kad- surenone. PF 5901 blocked ionomycm-induced LTB4 release but did not inhibit aggregation or degranulation induced by ionomycin, PAF, fMLP, or LTB4. Kad- surenone blocked PAF-induced aggregation and degranulation but not responses to LTB4, ionomycin, or fMLP. We conclude that LTB4 and PAF are potent activators of human PMNs that act independently of one another and that these lipids appear not to be involved in the responses to the other agonists studied. J. Leukoc. Biol. 53: 117–125; 1993.
Migratory responses of ovine neutrophils to inflammatory mediators in vitro and in vivo
Authors: Mulder K , Colditz IG 
Published: January 2018

Abstract
The migration of 111In-labeled ovine neutrophils toward a range of inflammatory mediators was examined in vitro using a 48-well chemotaxis chamber. Typical curves were obtained for the chemotactic response to zymosan-activated plasma (ZAP, a source of C5a) and interleukin-8 (EL-8). In contrast, leukotriene B4 (LTB4), platelet-activating factor (PAF), interleukin-lα (ILlα), tumor necrosis factor α (TNF-α), N-formyl-methionine-leucyl-phenylalanine (fMLP), and endotoxins from Escherichia coli and Pseudomonas aeruginosa failed to induce neutrophil migration in vitro. Of these mediators LTB4, ZAP, lL-lα, TNF-α, IFN-γ, and IL-8 have been reported to induce neutrophil accumulation in skin of sheep [1], and in the current study E. coU endotoxin was a potent inducer of 111In-labeled neutrophil accumulation and plasma leakage in skin. In contrast, PAF induced intense plasma leakage but failed to induce accumulation of 111In-labeled neutrophils in skin. Histologic examination of skin sites receiving PAF confirmed the failure of PAF to stimulate neutrophil extravasation. FMLP lacked inflammatory activity in skin. Coinjection of actinomycin D did not abrogate recruitment of neutrophils to skin sites receiving LTB4; thus neither induction of endothelial adhesion molecules nor synthesis of IL-8 was necessary for LTB4 to exhibit inflammatory activity in vivo. J. Leukoc. Biol. 53: 273–278; 1993.
Bidirectional modulation of TNF-α production by alveolar macrophages in asbestos-induced pulmonary fibrosis
Authors: Ouellet Sophie , Yang Huixin , Aubin Rémy A , Hawley Robert G , Wenckebach Georg F C , Lemaire Irma 
Published: January 2018

Abstract
Bronchoalveolar lavage (BAL) cells were isolated from rats 1, 3, and 6 weeks after a single intratracheal instillation of saline, UICC chrysotile asbestos (5 mg), or silica (5 mg). In asbestos-exposed rats, the pulmonary response was characterized by a significant increase in the number of alveolar macrophages (AMs) and the appearance of fibrotic lesions within 1 week. By contrast, mixed macrophage and neutrophile accumulations were observed in the silica group without evidence of fibrosis. Tumor necrosis factor-α (TNF-α) production by lipopolysaccharide (LPS)-stimulated BAL cells from asbestos-treated rats was significantly lower than controls 1 and 3 weeks after exposure. However, by 6 weeks higher levels of TNF-α production were noticeable in this group. Decreases in LPS-induced TNF-αon were also observed with BAL cells from silica-treated animals at all time points studied. Lower levels of TNF-a were not related to decreased BAL cell viability or the presence of a significant proportion of neutrophils in the silica group. Furthermore, biphasic changes in TNF-αtion seen in the asbestos group were correlated with concomitant decreases (3 weeks) and increases (6 weeks) in levels of TNF-α mRNA in AMs. These data indicate that lower levels of TNF-α resulted from inhibition at the gene expression level and provide evidence for bidirectional modulation of TNF-α production by AMs during inflammatory reactions. J. Leukoc. Biol. 53: 279–286; 1993.
Phorbol ester-induced degranulation in adherent human eosinophil granulocytes is dependent on CD11/CD18 leukocyte integrins
Authors: Egesten Arne , Gullberg Urban , Olsson Inge , Richter Johan 
Published: January 2018

Abstract
Secretion of unique eosinophil granule constituents may play a role in allergic and parasitic reactions. Therefore we have investigated possible mechanisms for regulation of secretion in eosinophils. A hemolytic plaque assay and an enzyme-linked immu-nospot (ELISPOT) assay were developed for detection of secreted eosinophil cationic protein (ECP) from single adherent eosinophils. The protein kinase C activator phorbol 12-myristate 13-acetate (PMA) induced release of ECP in a dose-dependent fashion but 4-αPMA, an analogue that does not activate protein kinase C, did not cause degranulation. Staurosporin and K252a, inhibitors of protein kinase C, decreased PMA-induced ECP secretion. Low concentrations of cytochalasin B enhanced PMA-induced secretion but high concentrations had an inhibitory effect. The calcium ionophores A23187 and ionomycin were weaker secretagogues than PMA. Tumor necrosis factor, granulocyte-macrophage colony-stimulating factor, interleukin-3, interleukin-5, N-formylmeth-ionyl-leucyl-phenylalanine, and lipopolysaccharide caused little or no degranulation in adherent eosinophils. Preincubation of eosinophils with antibodies to CD18, the common β chain of leukocyte adhesion proteins, resulted in inhibition of PMA-induced ECP release from adherent cells. l,2-Bis(O-aminophenyl)ethane-ethane-N,N,N,N′-tet-raacetic acid (BAPTA), an agent that acts intracellularly by chelation of calcium, also inhibited PMA-mediated ECP release. In conclusion, PMA induces release of ECP from single adherent eosinophils and the effect appears to be mediated via protein kinase C and, in contrast to that in neutrophils, to be dependent on CD11/CD18 leukocyte integrins. J. Leukoc. Biol. 53: 287–293; 1993.
Neutrophils contribute to hepatic ischemia- reperfusion injury by a CD18-independent mechanism
Authors: Langdale Lorrie A , Flaherty Lynne C , Liggitt H Denny , Harlan John M , Rice Charles L , Winn Robert K 
Published: January 2018

Abstract
Hepatic ischemia-reperfusion injury is reported to be modulated by neutrophils (PMNs). The adhesion and emigration of PMNs that precede tissue inflammation and necrosis in other organs are mediated, in part, by the leukocyte adhesion complex CD11/CD18. In this study, the role of PMN adhesion via CD11/CD18 in isolated liver ischemia-reperfusion injury was examined in rabbits using a blocking monoclonal antibody (mAb 60.3) specific for the GDI 8 receptor. Vinblastine- induced neutropenia provided significant protection, confirming participation of neutrophils in the pathogenesis of hepatic injury. Inhibition of PMN adherence with mAb 60.3 did not ameliorate injury, as measured by aminotransferase concentrations or a histologic scoring system for injury severity. Histologic sections were scored for pattern and extent of injury as well as neutrophil association with injury. These results suggest a CD18- independent mechanism of neutrophil adhesion in the evolution of isolated hepatic ischemia-reperfusion injury. J. Leukoc. Biol. 53: 511–517; 1993.
Intracellular multiplication of Legionella pneumophila in HL-60 cells differentiated by 1,25-dihydroxyvitamin D3 and the effect of interferon y
Authors: Watanabe Masayuki , Shimamoto Yoshinori , Yoshida Shin-ichi , Suga Kenji , Mizuguchi Yasuo , Kohashi Osamu , Yamaguchi Masaya 
Published: January 2018

Abstract
We examined leukemic cells, HL-60, an acute promyelocytic leukemia cell line, after differentiation induced by 1,25-dihydroxyvitamin D3 (D3) and retinoic acid (A) for infection of Legionella pneumophila, the etiologic agent of Legionnaires’ disease. We investigated the effect of interferon γ (IFN-γ) on the differentiated cells and on the intracellular growth of the bacteria. An examination of morphological and antigenic changes in the cells was also included in the study. After 4-day incubation with 10-6M D3 or A, the HL-60 cells differentiated into monocyte-like (D3-HL-60) or mature granulocyte-like (A-HL-60) cells, respectively. They were then infected with L. pneumophila. Intracellular multiplication of the bacteria was evident in D3-HL-60 cells but not in HL-60 or A-HL-60 cells. D3-HL-60 cells required a 24-h infection time for the intracellular growth of L. pneumophila. D3-HL-60 cells activated with human recombinant IFN-7 for 1-24 h (γ-IFN-D3-HL-60 cells) before infection markedly inhibited L. pneumophila multiplication, the effect of IFN-γ being dose dependent. Surface marker analysis was carried out in HL-60, D3-HL-60, and 7-IFN-D3-HL-60 cells. On D3-HL-60 cells, CDllb, CDllc, CD14, and CD35 antigen increased, whereas CD71 and HLA-DR antigen decreased. This finding suggested that HL-60 cells differentiated into monocyte-like cells; the acquisition of the complement receptors, CDllb(CR3) and CD35(CR1), seemed to be important for phagocytosis and for the subsequent intracellular multiplication of L. pneumophila. The γ-IFN- D3-HL-6O cells showed an increase of CD16, CD36, CD71, and HLA-DR antigen, suggesting that they were in an activated state. Our study indicated, first, that D3 can induce human leukemic cells to differentiate into functional monocyte-macrophage-like cells that can support the intracellular multiplication of L. pneumophila and, second, that these differentiated leukemic cells can be activated by IFN-γ to markedly inhibit bacterial growth.
The leukocyte surface antigens CD11b and CD18 mediate the oxidative burst activation of human peritoneal macrophages induced by type 1 fimbriated Escherichia coli
Authors: Gbarah Awni , Gahmberg Carl G , Boner Geoffrey , Sharon Nathan 
Published: January 2018

Abstract
Analysis by immunofluorescence-activated cell sorting of human peritoneal macrophages from patients undergoing intermittent peritoneal dialysis revealed that they express the CD11/CD18 surface antigens, with CDllb and CD18 as the predominant ones. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of im- munoprecipitates obtained from lysates of 125I-labeled macrophages with rabbit polyclonal antibodies against the CDlla-c/CD18 complex or against CD18, revealed four radioactive bands corresponding to CDlla, CDllb, CDllc, and CD18. Monoclonal antibodies against CDllb and CD18 inhibited by 80 and 90%, respectively, the oxidative burst activation of the macrophages by type 1 fimbriated Escherichia coli, whereas monoclonal antibodies against CDlla, CDllc, and CD43 were without effect. Our results suggest that CDllb and CD18 (receptors for C3bi) serve also as receptors for mannose-specific E. coli on human peritoneal macrophages and may be involved in the lectinophagocytosis of the bacteria by these cells.
Fibrosarcoma-induced increase in macrophage tumor necrosis factor α synthesis suppresses T cell responses
Authors: Alieva David G , Askew David , Burger Carol J , Elgert Klaus D 
Published: January 2018

Abstract
Tumors down-regulate T cell responses partly by increasing macrophage (mφ) production of the suppressive molecule prostaglandin E2 (PGE2). Because tumor growth increases mφ tumor necrosis factor a (TNF-α) production and TNF-α stimulates mφ PGE2 synthesis, we examined the contribution of TNF-α to fibrosarcoma-induced mφ -mediated suppression of allo- reactive CD4+ T cell proliferation. We showed that tumorbearing host (TBH) mφs express high levels of TNF-α mRNA, which leads to increased lipopolysaccharide- induced TNF-α production. Timor cells were directly involved in mφ TNF-α synthesis because fibrosarcoma cells induced normal host (NH) mφ s to produce TNF-α. Addition of TBH mφ s to allogeneic mixed lymphocyte reaction (MLR) cultures suppressed CD4+ T cell proliferation more than NH mφ s. The neutralization of endogenous TNF-α activity with anti-TNF-α antibody (Ab) treatment reversed TBH, but not NH, mφ -mediated suppression. Conversely, exogenous TNF-α increased NH or TBH mφ-mediated suppression but stimulated T cell proliferation without mφ s. Kinetic treatment of MLR cultures with anti-TNF-α Ab or TNF-α showed that TNF- αproduction and activity occurred at the beginning of T cell proliferation. When arachidonic acid metabolite synthesis was inhibited, TNF-α-induced suppression was blocked in NH mφ -containing cultures and completely reversed in TBH mφ-containing cultures. A PGErspecific enzyme-linked immunosorbent assay showed that TNF-a addition increased PGE2 production in NH mφ - containing cultures to that of TBH mφ -containing cultures. Exogenous PGE2 did not affect the TNF-α enhancement of T cell proliferation without mφ s. Therefore, suppression induced by TNF-α was caused by increased mφ PGE2 production and not by TNF-α in concert with PGE2. Even though TNF-a is known to enhance lymphocyte proliferation, we show that in the presence of mφs, the main TNF-α producers, TNF-α suppresses T cell proliferation. Perhaps increased TNF-α production during pathological states, such as cancer, triggers the initial stages of suppression.