bluuebunny/crossref_metadata_2025 huggingface dataset:
Mobilizable intracellular pool of p55 (type I) tumor necrosis factor receptors in human neutrophils
Authors: Porteu Françoise , Nathan Carl F
Published: January 2018

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

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

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

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

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

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

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

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

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

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

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

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.
Silica induces apoptosis in macrophages and the release of interleukin-1 α and interleukin-1β
Authors: Sarih M’hammed , Souvannavong Vongthip , Brown Spencer C , Adam Arlette
Published: January 2018

Resident adherent peritoneal cells selectively released high amounts of interleukin-1 (IL-1) activity when treated with silica. The use of anti-IL-1 antisera showed that both IL-Ια and IL-1β were present in supernatants of silica-treated macrophages. In contrast, intracellular IL-1 activity was totally neutralized by anti- IL-Ια antibodies and was easily converted into the mature IL-Ια form by autolysis in cytoplasmic extracts. Anion exchange chromatography clearly separated the two IL-1 species present in supernatants of silica- stimulated macrophages. Natural IL-1β was further characterized by chromatofocalization; it had an apparent isoelectric point, pI, in the range 8.3-8.6. In agreement with previous findings showing that IL-1/3 was released only by apoptotic cells, we have found that silica-treated macrophages underwent apoptosis. This was demonstrated by the characteristic laddering electrophoretic pattern of DNA extracted from silica-treated cells and by the morphology of macrophage nuclei stained with the DNA-specific dye DAPI. In addition, quantification of apoptotic cells was performed by a flow cytometric analysis based on the reduction of cellular DNA content exhibited by apoptotic cells. Treatment of macrophages with silica, therefore, results in an active process that promotes the processing and liberation of IL-1β.
Interplay between superantigens and the immune system
Authors: Irwin Michael J , Gascoigne Nicholas R J
Published: January 2018

Superantigens interact with the immune system by binding to major histocompatibility complex (MHG) class II proteins and activating T cells through the variable region of the T cell receptor β-chain. Through this means they can cause massive proliferation and then death of a large proportion of T cells. Superantigens are produced by bacteria, mycoplasmas, retroviruses, and probably by other organisms. In some cases, the superantigen is crucial to the organism’s life cycle. Mouse mammary tumor virus disseminates by activating T cells which stimulate the proliferation of B cells harboring the virus. In other cases, the superantigen may be responsible for the pathogenesis of the infection, such as in the case of Toxic Shock Syndrome. In this article, we review information on the diseases in which superantigens are involved, and the mechanisms by which the superantigens interact with T cell receptor and class II molecules.
A carboxyl-terminal tail peptide of neutrophil chemotactic receptor disrupts its physical complex with G protein
Authors: Bommakanti Rajani K , Klotz Karl-Norbert , Dratz Edward A , Jesaitis Algirdas J
Published: January 2018

The binding of G protein to the N-formyl peptide receptor of human neutrophils was investigated with site-specific synthetic peptides. Peptide CT336/332 (322RALTEDSTQTSDTAT336) from the carboxyl-terminal tail region of the receptor competed with the receptor for binding to bovine Gi protein. The peptide competition was assayed by dissociation of a GTP-sensitive, rapidly sedimenting (7S) form of receptor-G protein complex as analyzed by velocity sedimentation on linear sucrose density gradients. An IC50 of 590 μΜ was determined for CT336/332 peptide. A control peptide, with the reverse sequence, rCT 336/332(336 TATDSTQTSDETLAR322)did not perturb the sedimentation of the reconstituted receptor-G protein complex up to the highest tested concentration, 3 mM. Other peptides tested, corresponding to central portions of the predicted intracellular loop regions CII140/127 (127VLHPVWT QNHRTVS140) and CIII239/227 (227KIHKQGLIKSSRP239) of the receptor, failed to dissociate the reconstituted receptor-G protein complex. Control peptides from the extracellular region EII184/170 (170KTGTVACTFNFSPWT184) and an unrelated sequence matching a portion of neutrophil cytochrome b, CYT306/296 (296KWITKWTHPFKTIE306), were also ineffective. Our results suggest that the cytoplasmic tail of the formyl chemotactic peptide receptor is involved in its coupling to the signal-transducing G protein.
Influence of suspension on the expression of protective immunological memory to murine Listeria monocytogenes infection
Authors: Miller Edwin S , Sonnenfeld Gerald
Published: January 2018

Female BDF1 mice were immunized with virulent Listeria monocytogenes, which resulted in the generation of a long-lived state of protective immunological memory for this facultative intracellular bacterial pathogen. The influence of antiorthostatic suspension, a ground-based model employed to simulate certain aspects of weightlessness that occur during spaceflight, on the capacity of these mice to express memory immunity was evaluated. Memory-immune mice were suspended by the tail in the orthostatic or antiorthostatic position and were reinfected with a lethal dose of virulent L. monocyto- genes. It was found that suspension did not influence the kinetics of bacterial growth in vivo when the rechallenge infection was started concurrently with the suspension. However, mice that were reinfected on day 2 or 4 of the suspension exhibited an enhanced capacity to eliminate the infection. Attenuation of this enhancing effect was observed when mice were infected on day 7 of the suspension. These results indicate that the stress of antiorthostatic suspension can influence the capacity of the murine host to express protective immunological memory to pathogenic bacteria.
Processing and intracellular transport of cathepsin G and neutrophil elastase in the leukemic myeloid cell line U-937—modulation by brefeldin A, ammonium chloride, and monensin
Authors: Lindmark Anders , Gullberg Urban , Olsson Inge
Published: January 2018

The effects of brefeldin A, monensin, and the weak base NH4C1 on the biosynthesis and processing of cathepsin G and neutrophil elastase of myeloid cells were investigated. Monoblast-like U-937 cells were biosynthetically labeled with [35S]methionine, followed by subcellular fractionation, immunoprecipitation, and analysis by sodium dodecyl sulfate-polyacrylamide gel electrophore-sis and fluorography. Brefeldin A inhibited proteolytic processing, intracellular transport, and secretion. The effects were reversible inasmuch as removal of brefeldin A resulted in a normal pattern of processing and transfer to high-density organelles, corresponding to lysosomes, and restitution of constitutive secretion of precursor forms. Both cathepsin G and neutrophil elastase acquired resistance to endoglycosidase-H, suggesting that conversion to complex oligosaccharide side chains also occurs in the presence of brefeldin A. Monensin and NH4Cl inhibited final proteolytic processing, indicating either that acidification is necessary for directing cathepsin G and neutrophil elastase to lysosomal-like organelles or that the protease(s) responsible for processing requires an acid pH. We conclude that pH-dependent proteolytic processing of cathepsin G and neutrophil elastase occurs in post-Golgi structures and that transfer to lysosomes or an immediately prelysosomal compartment is mandatory for complete processing. J. Leukoc. Biol. 55: 50–57; 1994.
Inhibition by all-trans-retinoic acid of tumor necrosis factor and nitric oxide production by peritoneal macrophages
Authors: Mehta Kapil , McQueen Teresa , Tucker Stanley , Pandita Raj , Aggarwal Bharat B
Published: January 2018

Besides their growth-inhibiting and differentiation-inducing properties, retinoids have been shown to exert immunomodulatory and anti-inflammatory functions by mechanisms that are not well understood. Tumor necrosis factor-α (TNF), a cytokine produced by mononuclear phagocytes, has been shown to be an important mediator of endotoxin-induced septic shock, cachexia, bone resorption, and inflammation. Nitric oxide may also have a role in septic shock, hypotension, and vasodilatation. In this study, we examined the effects of retinoids on the production of TNF and nitric oxide by murine peritoneal macrophages. Of the various retinoids studied, all-trans-retinoic acid (RA) was most potent; it almost completely inhibited the production of TNF by macrophages activated with endotoxin and interferon-γ. The inhibitory effect was dependent on the dose and duration of RA exposure to macrophages. RA also blocked phorbol ester-induced TNF production in a macrophage cell line (RAW 264.7). Besides TNF, the retinoid suppressed the production of nitric oxide from activated peritoneal macrophages. The importance of these results in relation to controlling various harmful effects of cytokines released by activated macrophages is discussed. J. Leukoc. Biol. 55: 336–342; 1994.
Influence of antiorthostatic suspension on resistance to murine Listeria monocytogenes infection
Authors: Miller Edwin S , Sonnenfeld Gerald
Published: January 2018

The present study was designed to evaluate the influence of antiorthostatic suspension, a ground-based modeling system employed to simulate certain aspects of weightlessness that occur during space flight, on the capacity of mice to resist infection with the facultative intracellular bacterial pathogen Listeria monocytogenes. Female BDF1 mice were suspended by the tail in the orthostatic or antiorthostatic position and were infected with a sublethal dose of virulent L. monocytogenes at various times during the suspension. It was found that suspension did not influence the kinetics of bacterial growth in vivo if the infection was started concurrently with the suspension. However, mice that were antiorthostatically suspended 2, 4, or 7 days before the onset of infection exhibited an enhanced capacity to eliminate the challenge infection. Suspending mice on day 2 of the infection did not alter the kinetics of bacterial growth. Finally, the enhancement of resistance to the primary Listeria infection was accompanied by failure of the mice to generate long-term protective immunological memory to the challenge organism. Collectively, these results indicate that the stress of antiorthostatic suspension can influence the capacity of mice to resist bacterial infection. J. Leukoc. Biol. 55: 371–378; 1994.
Expression of p47-phox and p67-phox proteins in murine bone marrow–derived macrophages: Enhancement by lipopolysaccharide and tumor necrosis factor α but not colony stimulating factor 1
Authors: Green Simon P , Hamilton John A , Uhlinger David J , Phillips Wayne A
Published: January 2018

We have investigated the relationship between the expression of the p47-phox and p67-phox cytosolic components of the NADPH oxidase and priming of the macrophage respiratory burst. Western blot analysis revealed that murine bone marrow-derived macrophages (BMM) contain immunoreactive proteins detected by antisera raised against recombinant human p47-phox and  p67-phox. Priming BMM by exposure to tumor necrosis factor or (TNF-α) or lipopolysaccharide (LPS) increased the levels of p47-phox and p67-phox. Colony-stimulating factor 1 (CSF-1), which we previously found to have a negative effect on the priming of murine macrophages, had no effect on the level of p47-phox but down-regulated that of p67-phox. Our results suggest that the regulatory effects of LPS, TNF-α, and CSF-1 on the respiratory burst of BMM may be due to modulation of the expression of the p47-phox and p67-phox cytosolic components of the NADPH oxidase. J. Leukoc. Biol. 55: 530–535; 1994.
Quantification of neutrophil migration following myocardial ischemia and reperfusion in cats and dogs
Authors: Albertine Kurt H , Weyrich Andrew S , Ma Xin-liang , Lefer David J , Becker Lewis C , Lefer Allan M
Published: January 2018

Endothelial cell dysfunction and cardiac myocyte injury resulting from ischemia and reperfusion have been associated with accumulation of neutrophils in the myocardium. To determine whether the accumulation is related primarily to intravascular sequestration or extra-vascular infiltration of neutrophils during the early period of reperfusion, we morphometrically quantified the tissue distribution of neutrophils in cats and dogs. At the end of the reperfusion period, the base of the heart was cross-clamped to preserve neutrophil location at the moment of death. Point-counting methods were used to determine the distribution of neutrophils inside and outside coronary arterioles and venules (≤100 μm in diameter) as well as coronary capillaries 5–10 μm in diameter in 0.5-μm-thick, plastic-embedded sections. Ischemia-reperfusion resulted in a threefold increase in neutrophil number in the lumen of arterioles and venules at 60 min of reperfusion and up to a sevenfold increase at 270 min of reperfusion (P < .05) compared to time-matched control nonischemic hearts. The ratio of intravascular neutrophils in venules to arterioles was 2:1. Intracapillary neutrophils increased, but not significantly, at 60 min of reperfusion. At 270 min of reperfusion, intracapillary neutrophils increased 11-fold (P < .05). The percentage of total neutrophils that accumulated outside arterioles and venules in cat hearts was 8% at 60 min of reperfusion (not significant, NS) and 28% at 270 min of reperfusion (P < .05). In dog hearts, the percentages were 26% (NS) and 44% (P < .05), respectively. The percentage of total neutrophils that accumulated outside capillaries was <6% in both cat and dog hearts (NS). The combination of rapid intravascular sequestration, delayed extravascular infiltration, and low incidence of neutrophil–cardiac myocyte contact in situ in these two species suggests that neutrophil-mediated cardiac myocyte injury during early reperfusion may initially depend on diffusion of inflammatory mediators and subsequently require direct contact between neutrophils and cardiac myocytes. J. Leukoc. Biol. 55: 557–566; 1994.
The role of G-CSF in mature neutrophil function is not related to GM-CSF-type cell priming
Authors: Treweeke Andrew T , Aziz Khalil A , Zuzel Mirko
Published: January 2018

Because of uncertainties regarding the comparability of granulocyte-macrophage and granulocyte colony-stimulating factors with regard to their effects on mature neutrophils (PMNs), we compared the actions of the two cytokines on reactive oxidant production and granular secretion by these cells. We found that chemiluminescence (CL) stimulated by formylmethionyl-leucylphenylalanine (fMLP) was not influenced by G-CSF (0.1–100 ng/ml), whereas GM-CSF priming (10 ng/ml) caused a nearly twofold increase in this PMN response. Moreover, the reactivity of PMNs treated with GM-CSF and G-CSF in combination was not different from that of PMNs treated with GM-CSF alone. GM-CSF (10 ng/ml) increased the rate of O2- production by 79%, caused a fivefold increase in fMLF-induced myeloperoxidase (MPO) secretion, and strongly enhanced CD11b expression. In contrast, G-CSF (50 ng/ml) only slightly increased O2- production (by 15%), and MPO secretion and CD11b expression remained unchanged. Both cytokines together gave results similar to those obtained with GM-CSF alone. In the presence of platelets (which by themselves enhanced PMN reactivity), the differences in the effects of the two cytokines persisted. We conclude that the priming effect of G-CSF on mature PMNs is negligible compared with that of GM-CSF. Our results are in conflict with previous reports of much more pronounced G-CSF effects but in accord with recent work showing the failure of this cytokine to induce a range of effects produced by GM-CSF. We therefore suggest that the primary role of G-CSF in mature PMN function is still unclear but may be related to the control of PMN distribution in view of the mobilizing and marginating effects of the cytokine in viva J. Leukoc. Biol. 55: 612–616; 1994.
Rat CINC/gro: a novel mediator for locomotive and secretagogue activation of neutrophils in vivo
Authors: Suzuki Hidekazu , Suematsu Makoto , Miura Soichiro , Liu Yu Ying , Watanabe Kazuyoshi , Miyasaka Masayuki , Tsurufuji Susumu , Tsuchiya Masaharu
Published: January 2018

The effects of rat CINC/gro, a member of the interleukin-8 family, on the endothelium-neutrophil interaction and transendothelial macromolecular leakage were studied in rat mesenteric microcirculation. Thirty minutes after superfusion with 10 nM CINC/gro, the number of neutrophils adherent to the venular endothelium and those migrated across the venules were significantly increased with a concomitant elevation of luminol-dependent chemiluminescence at the site of adhesion. Transendothelial macromolecular leakage as assessed by the relative length of venular wall stained with monastral blue B was also increased at 30 min after the start of CINC/gro superfusion. Pretreatments with a CD18-directed monoclonal antibody, WT-3 (1 mg/kg), significantly attenuated the increase in number of adherent and migrated neutrophils, the increase in luminol-dependent chemiluminescence, and the venular macromolecular leakage after the application of CINC/gro. These data suggest that CINC/gro is a novel stimulator that evokes not only locomotive but also secretagogue activation of neutrophils via a CD18-dependent mechanism in viva J. Leukoc. Biol. 55: 652–657; 1994.
Nitric oxide (NO)–induced mitochondrial injury among chicken NO-generating and target leukocytes
Authors: Sung Yen-Jen , Dietert Rodney R
Published: January 2018

In an analysis of nitric oxide (NO) production and toxicity, chicken macrophage–generated NO inhibited mitochondrial activity in both NO-producing macrophages themselves and lymphoid tumor targets. However, differences in targeting of mitochondrial toxicity were observed among these cells. Two chicken macrophage cell lines, HD11 and MQ-NCSU, produced NO (measured as nitrite) dependent upon concentrations of l-arginine and bacterial endotoxin (lipopolysaccharide). Mitochondrial activity was negatively correlated with the amount of NO produced. Using a modified MTT assay, NO induced suppression in two mitochondrial complexes. Mitochondrial activity was significantly suppressed among HD11 cells receiving LPS alone (complex I, 63.0 ± 5.5% suppression; complex II, 27.9 ± 5.2%). In contrast, mitochondrial activities in samples receiving LPS plus inhibitor, NG-nitro-l-arginine methyl ester (NAME; 5 mM) or 2,4-diamino-6-hydroxypyrimidine (DAHP; 5 mM), were not significantly different from control values. When HD11 macrophages were cocultured with lymphoblastoid tumor targets, RECC-CU60 (T cell) or LSCC-RP9 (B cell), adding LPS (1 μg/ml), tumor cell mitochondrial activity was significantly suppressed. In the generator macrophages, complex I was more suppressed than complex II, whereas in lymphoid targets no such difference was observed. These results indicate that NO inhibits complex I and II mitochondrial activity but that differential targeting can occur among chicken leukocyte populations J. Leukoc. Biol. 56: 52–58; 1994.
Influence of interleukin-1 on neutrophil function and resistance to Streptococcus suis in neonatal pigs
Authors: Shi J , Goodband R D , Chengappa M M , Nelssen J L , Tokach M D , McVey D S , Blecha F
Published: January 2018

Nonspecific immunity is usually lower in neonates than adults. Consequently, enhancing the neonate’s nonspecific immune capability may be beneficial for the health and growth performance of young animals. We conducted two experiments in which neonatal pigs were injected with recombinant bovine interleukin-1β (rBoIL-1β) at 9 to 11 days of age. Three consecutive daily injections of rBoIL-1β increased neutrophil and monocyte numbers, which remained elevated until the animals were challenged with Streptococcus suis at 19 days of age. Neutrophil bactericidal activity was greater in interleukin-1-treated pigs than in saline-injected controls. At lower ratios of effector to target cells, neutrophil-mediated, antibody-dependent cellular cytotoxicity was increased in neonates treated with IL-1. However, natural killer cell activity and neutrophil production of superoxide anion were not affected by treatment with IL-1. Expression of CD18 was increased transiently on neutrophils from IL-1-treated pigs at 15 days of age. Severity of the streptococcal infection was less in pigs that were treated with IL-1 at 9 to 11 days of age. These data suggest that IL-1 treatment in neonates may augment nonspecific immune function and disease resistance. J. Leukoc. Biol. 56: 88–94; 1994.
Role of endotoxin in mononuclear phagocyte-mediated inflammatory responses
Authors: Watson R W G , Redmond H R , Bouchier-Hayes D
Published: January 2018

Lipopolysaccharide (LPS), which is derived from the cell wall of gram-negative and some gram-positive bacteria, plays a major role is the pathogenesis of septic shock. Initiation of these responses depends on LPS interaction with a number of immune cells, not least the mononuclear phagocyte (MP). Mononuclear phagocytes bind the LPS/lipopolysaccharide-binding protein complex through the CD14 receptor and thus mediate the release of a wide range of inflammatory mediators. Release of these mediators is teleologically beneficial but under certain circumstances may be detrimental, resulting in the systemic inflammatory response syndrome. The development of this syndrome is not clearly understood but appears, in part, to be dependent on the ability of the host to respond to these mediators. This review evaluates the mechanisms of LPS-MP interaction and the therapeutic strategies aimed at inhibiting this interaction. J. Leukoc. Biol. 56: 95–103; 1994.
Requirement for lymphocytes and resident macrophages in LPS-induced pleural eosinophil accumulation
Authors: Bozza Patricia T , Castro-Faria-Neto Hugo C , Penido Carmen , Larangeira Andréa P , Graças Maria das , Henriques M O , Silva Patricia M R , Martins Marco A , dos Santos Ricardo Ribeiro , Cordeiro Renato S B
Published: January 2018

In this study we investigated the involvement of inflammatory cells in the pleural accumulation of eosinophils induced by lipopolysaccharide (LPS). Intrathoracic (i.t.) injection of LPS (250 ng/cavity) into rats induced a significant eosinophil accumulation that developed within 24 h, was maximal at 48 h, and returned to control values within 120 h. This eosinophil influx was preceded by a huge neutrophil influx within 4 h and accompanied by a mononuclear cell accumulation between 24 and 48 h. Pretreatment with an antineutrophil monoclonal antibody (RP-3, 2 ml per animal) selectively reduced the number of circulating neutrophils within 8 h but failed to alter the LPS-induced eosinophilia. Similarly, platelet depletion with an anti-rat platelet antiserum did not alter the LPS-induced eosinophil accumulation. Cyclosporine (50 mg/kg, 12 and 2 h before) partially inhibited (51%) the LPS-induced pleural eosinophilia, whereas the eosinophilia was not changed by prior degranulation of pleural mast cells with polymyxin B (10 μg/cavity, 24 h before). Moreover, selective depletion of T lymphocytes using an anti-Thy 1.0 monoclonal antibody significantly inhibited the eosinophilia triggered by LPS. The i.t. injection of liposomes containing dichloromethylene diphosphonate significantly reduced (65%) the number of resident macrophages after 5 days. Under this condition, the eosinophil infiltration induced by LPS was completely inhibited. Accordingly, the i.t. injection of supernatant from macrophage monolayers, obtained from the pleural cavities of LPS-injected rats, into naive recipient animals led to a twofold increase in the number of pleural eosinophils. In conclusion, our data suggest an important role for resident macrophages and T lymphocytes in the eosinophil accumulation induced by LPS. J. Leukoc. Biol. 56: 151–158; 1994.
Functional characterization of peripheral circulating and liver recruited neutrophils in endotoxic rats
Authors: Spitzer J A , Zhang P , Mayer A M S
Published: January 2018

Neutrophil accumulation in tissues is a hallmark of inflammation and is associated with a variety of pathological conditions. In bacterial infection neutrophils are selectively attracted in large numbers to phagocytose and kill invading microorganisms. However, activated neutrophils can also cause injury to tissues. To investigate functional alterations in liver recruited neutrophils (PMNs), we studied the functional characteristics of circulating blood and liver sequestered PMNs in terms of host defense mechanisms, such as nitric oxide (NO) and superoxide (SO) generation, β  2 integrin expression, phagocytosis, and eicosanoid profile. Cells were isolated from rats infused with a nonlethal dose (320 μg/kg) of E. coli endotoxin (ET) or pyrogen-free saline for 90 min. Liver PMNs produced significantly more NO both in the absence and in the presence of an in vitro endotoxin challenge than did blood PMNs. No significant difference was observed in phorbol myristate acetate-stimulated SO generation. Endotoxin infusion significantly up-regulated the expression of CD11b/c in circulating and even more so in liver PMNs. Phagocytosis was significantly enhanced by in vivo ET treatment in blood PMNs, and liver PMNs showed even greater phagocytic activity than blood PMNs or Kupffer cells. The percent distribution of prostaglandins D2 and E2 of total 14C-eicosanoids was significantly higher and that of thromboxane B2 and 5-, 12-, and 15-HETEs was significantly lower in liver than in blood PMNs. Our study demonstrates several functional differences between liver-recruited and circulating PMNs in an acute endotoxic model. The implications of altered neutrophil function may extend to mechanisms of host defense and hepatotoxicity associated with sepsis and endotoxemia. J. Leukoc. Biol. 56: 166–173; 1994.
HIV infection of placental macrophages: their potential role in vertical transmission
Authors: Kesson Alison M , Fear Warwick R , Williams Lindy , Chang Joon , King Nicholas J C
Published: January 2018

Placental macrophages were isolated and cultured in vitro to investigate their susceptibility to HIV infection and possible role in vertical transmission of HIV. After 10 days of in vitro culture the cells were positive for nonspecific esterase and acid phosphatase and negative for myeloperoxidase and placental alkaline phosphatase. They expressed cell surface HLA-ABC, HLA-DR, CD45, as well as CD68 intracellularly, as detected by flow cytometry, confirming their macrophage lineage. Approximately 80% of cells expressed surface CD14. CD4 antigen was expressed at very low levels and was confirmed by antibody blocking experiments. Infection of placental macrophage cultures with HIV resulted in a transient peak of viral replication 3 to 7 days after infection, but no later rise in HIV was detected with culture of up to 60 days. HIV replication was not up-regulated by coculture with phytohemagglutinin-stimulated lymphocytes or by treating infected cultures with tumor necrosis factor α or granulocyte-macrophage colony-stimulating factor. J. Leukoc. Biol. 56: 241–246; 1994.