bluuebunny/crossref_metadata_2025_split huggingface dataset:
Neopterin production by HIV-1–infected mononuclear phagocytes
Authors: Dukes Carol S , Matthews Thomas J , Rivadeneira Emilia D , Weinberg J Brice 
Published: January 2018

Abstract
Neopterin is a pteridine produced by human mononuclear phagocytes, usually in response to interferon-γ (IFN-γ) stimulation. Increasing serum levels of neopterin correlate with clinical progression to AIDS in HIV-infected people, but the factors that contribute to these elevated levels are not established. We performed in vitro experiments to investigate the possibility that HIV-1 infection of mononuclear phagocytes directly induces enhanced neopterin production. We found that HIV-1-infected monocytes and peritoneal macrophages produced neopterin in quantities similar to amounts produced by uninfected cells. The HIV-infected cells responded to stimulation with IFN-γ as well as uninfected cells, with a 6- to 12-fold increase in neopterin production. We conclude that elevated serum levels of neopterin in HIV-infected individuals are not caused by HIV-1 infection of mononuclear phagocytes but may be a result of the normal response of mononuclear phagocytes to increased levels of IFN-γ. J. Leukoc. Biol. 56: 650–653; 1994.
Determinants of neutrophil HOCI generation: ligand-dependent responses and the role of surface adhesion
Authors: Chatham W Winn , Turkiewicz Anthony , Blackburn Warren D 
Published: January 2018

Abstract
Neutrophil (PMN) generation of HOCI, an oxidant important in mediating tissue injury by PMN proteases, requires PMN production of H2O2 and the catalytic activity of myeloperoxidase (MPO). Production of H2O2 and MPO release vary with the PMN activating ligand and are facilitated by cellular adhesion. Leukotriene B4, platelet-activating factor, heat-aggregated immunoglobulin G (HAIgG), tumor necrosis factor α (TNF-α), and f-Met-Leu-Phe (fMLP) all triggered significant superoxide production but negligible H2O2 or HOCI generation when added to suspended PMNs. Production of H2O2 was observed when fMLP, TNF-α, or HAIgG was added to PMNs adherent to bovine serum albumin (BSA)-coated wells, but significant production of HOCI was observed only when HAIgG was added to PMNs adherent to BSA-coated wells or when suspended PMNs treated with TNF-α were allowed to settle in BSA-coated wells. Even greater production of both H2O2 and HOCI was observed when PMNs were incubated in wells coated with IgG (SAIgG). HOCI generation, when observed, was accompanied by release of MPO. Nonadherent PMNs generated HOCI when treated with 50–100 ng/ml phorbol myristate acetate or when stimulated with fMLP following treatment with cytochalasin B; PMN activation under these conditions was also associated with MPO release but HOCI production was much less efficient relative to PMNs stimulated by SAIgG. These studies indicate that surface adhesion and ligand-induced responses that facilitate release of myeloperoxidase and dismutation of superoxide to H2O2 are required for production of extracellularly released HOCI; these responses are most efficiently utilized during PMN interaction with SAIgG. J. Leukoc. Biol. 56: 654–660; 1994.
Neutrophils, host defense, and inflammation: a double-edged sword
Authors: Smith John A 
Published: January 2018

Abstract
Neutrophils play important roles in host defense against all classes of infectious agents but, paradoxically, they are also involved in the pathology of various inflammatory conditions. Their microbicidal armory consists of oxidative and nonoxidative processes that are activated simultaneously upon phagocytosis. Although destruction of infectious agents occurs intracellularly, release of cytotoxic molecules into the extracellular milieu can damage body tissues. Neutrophils are heterogeneous. Subpopulations exist in various stages from dormant to primed to fully activated. The activities of neutrophils are regulated locally in microenvironments and systemically by a plethora of mediators including cytokines, “classical” neuroendocrine hormones, and bioactive lipids. The net response depends on a complex balance of stimulatory and inhibitory pathways that are regulated by these mediators. Although some effector and regulatory pathways are vital, considerable redundancy is also evident. Identification of the essential mediators and the unraveling of any interactions may be the keys to understanding the neutrophil paradox and developing therapeutic strategies that optimize microbial killing and minimize host tissue damage. Finally, reports that neutrophils can act as drug delivery vectors and that their function is influenced by stress and other lifestyle factors suggest that new homeostatic functions for these cells, outside their traditional roles in host defense and inflammation, remain to be identified: some are speculated on here. J. Leukoc. Biol. 56: 672–686; 1994.
Summary of the Fifth Conference on the Molecular Mechanisms and Physiological Activities of Cytokines
Authors: Oppenheim Joost J 
Published: January 2018

Abstract
The conference organizers, Drs. Joost J. Oppenheim, Benjamin Sredni, Jan Vaage, and David W. Weiss, were ably advised by a program committee consisting of a number of participants from the previous conference, many of whom participated in the present meeting.
Quantitative recovery of pulmonary intravascular macrophages from sheep lungs
Authors: Rogers Rick A , Tasat Debora R , Warner Angeline E , Brain Joseph D 
Published: January 2018

Abstract
Pulmonary intravascular macrophages (PIMs) adhere to the endothelium of lung capillaries and sequester circulating particles and pathogens from the blood. Iron oxide (γFe203) 5 mg/kg, administered intravenously, specifically labeled PIMs in situ within the living sheep. Attempts to isolate γFe203-labeled PIMs using vascular perfusion (VP) procedures yielded few cells. To improve recovery of PIMs, a proteolytic lung digestion (PLD) procedure was developed. Following PLD, γFe203-containing PIMs were recovered by magnets and the amount of γFe203 present measured by fluxgate magnetometry. Proteolytic lung digestion recovered 34% of the total γFe203 in lung samples and yielded 2 105 PIMs/g lung with 95% viability. In contrast, VP recovered only 3% of the total γFe203 in the lung; furthermore, less than 2% of the recovered γFe203 was cell associated. Proteolytic lung digestion followed by magnetic separation is an effective way to recover viable sheep PIMs for in vitro study. J. Leukoc. Biol. 56: 692–701; 1994.
Human neutrophils are selectively activated by independent ligation of the subunits of the CD11b/CD18 integrin
Authors: Petersen Meryl M , Steadman Robert , Williams John D 
Published: January 2018

Abstract
The yeast cell wall preparation zymosan is a particulate stimulus for human neutrophils (PMNs). Unopsonised zymosan particles bind to the PMN CD11b/CD18 integrin and are phagocytosed, leading to activation of the 5-lipoxygenase pathway and release of the lipid chemotaxin leukotriene B4 (LTB4). Specific monoclonal antibodies (mAbs) to CD11b and to CD18 were used in the present study to evaluate the contribution of each chain to these processes. All four anti-CD18 mAbs but none of five anti-CD11b mAbs dose-dependently blocked PMN phagocytosis of zymosan. Nevertheless, all anti-CD11b mAbs and all anti-CD18 mAbs significantly inhibited zymosan-stimulated LTB4 release in a dose-dependent manner. In addition, there was a dose-dependent stimulation of LTB4 release resulting from the specific ligation and cross-linking of either chain of the integrin heterodimer. Thus zymosan-stimulated LTB4 release is initiated by signals from both chains of the CD11b/CD18 integrin, whereas only CD18 is essential for phagocytosis. J. Leukoc. Biol. 56: 708–713; 1994.
Activation of arachidonic acid metabolism in mouse macrophages by bacterial amphiphiles
Authors: Card George L , Jasuja Rahul R , Gustafson Gary L 
Published: January 2018

Abstract
The relative activities of lipoteichoic acid (LTA) from four Gram-positive bacteria were compared to different lipopolysaccharide (LPS) preparations for activation of arachidonic acid metabolism in mouse peritoneal macrophages. Total eicosanoid was determined in cultures labeled with [3H]-arachidonic acid. Prostaglandin E2 (PGE2) and leukotriene C4 (LTC4) were determined by EIA analysis. The relative potencies of the different preparations were: smooth LPS from Salmonella abortus ≥ Re-LPS from Salmonella minnesota (R-595) ≥ LTA from Streptococcus pyogenes Streptococcus faecalis Staphylococcus aureus ≥ monophosphoryl lipid A derived from the Re-LPS &gt; &gt; LTA from Bacillus subtilis. Activation of eicosanoid release was inhibited by staurosporin for all of the amphiphiles tested. Treatment of the macrophage cultures with LTA from S. pyogenes, S. faecalis, and S. aureus, either in the presence or absence of indomethacin, desensitized the cells to eicosanoid release on subsequent challenge with LPS. The desensitized cells remained responsive to the phorbol ester phorbol myristate acetate. LPS from Gram-negative bacteria has immunostimulatory and endotoxic activities which result, in part, from the release of eicosanoids and other mediators from activated macrophages. The similarities in the patterns of cell activation by LPS and LTA suggest that lipoteichoic acids might contribute to the pathogenicities of Gram-positive bacteria. J. Leukoc. Biol. 56: 723–728; 1994.
Human microglial cells have phenotypic and functional characteristics in common with both macrophages and dendritic antigen-presenting cells
Authors: Ulvestad Elling , Williams Kenneth , Bjerkvig Rolf , Tiekotter Kenneth , Antel Jack , Matre Roald 
Published: January 2018

Abstract
Resting microglia comprise up to 13% of the cells in human central nervous system (CNS) white matter. Their large number and dendritic morphology make them ideally suited to survey the CNS for noxious stimuli. Upon activation microglia gradually lose dendritic processes and transform into typical phagocytic macrophages. Microglia have been implicated as the main antigen presenting cell within the CNS, and appear to be of central importance as effectors and regulators of demyelination. To further characterize the capacity for immune reactivity within the human CNS, we have studied several characteristics of microglia, both in situ and in vitro. We find that human microglia have ultrastructural, phenotypic (CD11c, CD68, acid phosphatase), and functional (FcR and CR mediated phagocytosis) properties typical for cells of the monocyte lineage. Our data indicate that microglia also have properties in common with dendritic antigen-presenting cells. Electron microscopy studies show extended dendritic cell processes on cultured microglia, and microglia are, like dendritic cells, negative for the monocyte markers nonspecific esterase, endogenous peroxidase, CD14, and RFD7. Microglia constitutively express HLA-DR in situ, and express the dendritic cell marker RFD1 upon activation. Coculturing of microglia with CD4+ T cells results in clustering of T cells around microglia and initiation of a mixed lymphocyte reaction, both distinguishing features of dendritic cells. These functional properties of microglia may be of importance for the maintenance of an immunologic response in the CNS, an organ where dendritic cells, in contrast to other organs, have not previously been identified. J. Leukoc. Biol. 56: 732–740; 1994.
Modulation of the chemotactic responsiveness of guinea pig neutrophils to hrIL-8 and fMLP
Authors: Dai Yalei , Holgate Stephen T , Church Martin K , Shute Janis K 
Published: January 2018

Abstract
Neutrophils elicited in the peritoneal cavity of guinea pigs were purified on Percoll gradients and their chemotactic response to hrIL-8 and fMLP measured in vitro. hrIL-8 and fMLP were effective chemoattractants with optimal concentrations of 6 10-9 and 1 10-7 M, respectively. Scatchard analysis revealed approximately 205,000 IL-8 receptors/cell and 34,000 fMLP receptors/cell with K d values of 4.1 10-9 and 3.3 10-8 M, respectively. At suboptimal concentrations of chemoattractants the response was inhibited by dibutyryl cyclic AMP, histamine, and adenosine in the presence of a phosphodiesterase inhibitor. IL-8 and fMLP induced an increase in cellular cyclic AMP and the response to optimal concentrations of chemoattractants was inhibited by Calphostin C and Ro 31-8220, inhibitors of protein kinase C (PKC). Our results indicate that the chemoattractants activate the same PKC-dependent pathway that is down-regulated by cyclic AMP-dependent mechanisms. J. Leukoc. Biol. 56: 776–783; 1994.
Glycosylphosphatidylinositol-anchored NAD glycohydrolase is released from peritoneal macrophages activated by interferon-γ and lipopolysaccharide
Authors: Han Myung Kwan , Yim Chang-Yeol , An Nyeon-Hyoung , Kim Hyung-Rho , Kim Uh-Hyun 
Published: January 2018

Abstract
We have previously shown that an ectoenzyme, NAD glycohydrolase (NADase) could be solubilized by treatment with bacterial phosphatidylinositol phospholipase C (PIPLC). However, it is unknown whether endogenous PIPLC can cleave this ectoenzyme. In this study, we used mouse peritoneal exudate macrophages which have been known to have relatively high activity of NADase. The results show that release of ecto-NADase was markedly increased when mouse peritoneal macrophages were costimulated with interferon-γ (IFN-γ) and bacterial lipopolysaccharide (LPS), compared to unstimulated cells. This increase was preceded by markedly enhanced activity of endogenous glycosylphosphatidy-linositol phospholipase C (GPIPLC). The cross-reacting determinant (CRD) of the glycosylphosphatidylinositol anchor in released NADase from activated macrophages was detected by immunoblotting with anti-CRD antibody. Taken together, ecto-NADase is released from peritoneal exudate macrophages during IFN-γ/LPS-induced activation and endogenous GPIPLC is involved in the NADase release from the activated macrophages. J. Leukoc. Biol. 56: 792–796; 1994.
Ligation of CD23 activates soluble guanylate cyclase in human monocytes via an L-arginine–dependent mechanism
Authors: Paul-Eugène Nathalie , Kolb Jean-Pierre , Sarfati Marika , Arock Michel , Ouaaz Fateh , Debré Patrice , Mossalayi Djavad M , Dugas Bernard 
Published: January 2018

Abstract
Transduction through FcR2/CD23 was analyzed in normal human monocytes using immunoglobulin E (IgE)-anti-IgE immune complexes (IgE ICs) and monoclonal antibodies (mAbs) to CD23. Anti-CD23 mAb and IgE IC triggered a time-dependent increase in cGMP and cAMP in interleukin-4–preincubated (CD23+) but not in unstimulated (CD23-) monocytes. Maximal cGMP and cAMP accumulations were observed 10 and 20 min, respectively, after the onset of CD23 ligation. The increase in cGMP was inhibited with Nω-monomethyl-l-arginine (L-NMMA), which also partially affected cAMP accumulation. Addition of an anti-CD23 mAb Fab fragment inhibited the IgE IC– and the anti-CD23 mAb–induced cGMP and cAMP accumulation, confirming the engagement of CD23. In addition, IgE IC and anti-CD23 mAb induced, at least in some donors, a production of nitrite that was inhibited in the presence of L-NMMA. Taken together, these findings suggest a possible involvement of the nitric oxide synthase pathway in IgE IC–mediated activation of CD23+ monocytes. J. Leukoc. Biol. 57: 160–167; 1995.
Expression of both types of human interleukin-8 receptors on mature neutrophils, monocytes, and natural killer cells
Authors: Morohashi Hirohisa , Miyawaki Toshio , Nomura Hideki , Kuno Kouji , Murakami Seishi , Matsushima Kouji , Mukaida Naofumi 
Published: January 2018

Abstract
cDNA cloning revealed the presence of two related but distinct types of human interleukin-8 (IL-8) receptors, type I (type A) and type II (type B). By immunizing rabbits with glutathione-S-transferase fused with the NH2-terminal domain of each type of IL-8 receptor, we prepared polyclonal antibodies that specifically recognized the NH2-terminal domain of each type of IL-8 receptor. Immunofluorescence analysis of human peripheral blood leukocytes demonstrated that mature granulocytes except eosinophils express both types of IL-8 receptors. A majority of monocytes and CD16+ natural killer (NK) cells in peripheral blood were stained with both antibodies, whereas CD3+ T or CD20+ B lymphocytes in peripheral blood or CD34+ cells in cord blood were not stained with either antibody. These results suggest that both types of human IL-8 receptors were coordinately and selectively expressed in mature granulocytes, monocytes, and CD16+ NK cells. J. Leukoc. Biol. 57: 180–187; 1995.
Distinct granzyme expression in human CD3- CD56+ large granular- and CD3- CD56+ small high density-lymphocytes displaying non-MHC-restricted cytolytic activity
Authors: Smyth Mark J , Browne Kylie A , Kinnear Beverley F , Trapani Joseph A , Warren Hilary S 
Published: January 2018

Abstract
Cultured natural killer (NK) cells derived from CD3- CD56+ high-density small lymphocytes (HDLs) exhibit similar morphology and high levels of non-major histocompatibility complex-restricted (NK) cytotoxicity equivalent to those of cultured NK cells from CD3- CD56+ low-density large granular lymphocytes (LGLs). To examine the similarities and differences between NK cells from HDLs and NK cells from LGLs, we investigated the expression of three distinct members of the granule serine protease (granzyme) family within cultured CD3- CD56+ LGLs and HDLs. CD3- subpopulations of nonadherent peripheral blood mononuclear cells, LGLs (density &lt; 1.063 g/ml), and HDLs (density &gt;1.063 g/ml) were stimulated to proliferate in culture. The cultured cells from each population were entirely CD3- CD56+ and were indistinguishable in terms of their increased granularity and size once activated. All cultured CD3- CD56+ LGLs and HDLs displayed cytolytic activity against K562 and immunoglobulin-coated P815. Western analysis detected perforin in both cultured LGL and HDL populations. Cultured HDLs and LGLs both expressed BLT-esterase activity and human granzyme A mRNA. Granzyme B mRNA and protein and Asp-ase activity were detected in unstimulated and cultured LGLs and cultured HDLs. By contrast, unstimulated HDLs did not express significant levels of granzyme B. High levels of Hu-Met-1 granzyme mRNA and Met-ase activity were detected only in cultured LGLs. Thus, despite the development of large granular morphology during proliferation, interleukin-2 cultured CD3- CD56+ HDLs display a different pattern of granzyme expression from CD3- CD56+ LGLs. These data also further suggest an unusually restricted expression of the Hu-Met-1 granzyme in LGLs. J. Leukoc. Biol. 57: 88–93; 1995.
Temporal and spatial changes of quinolinic acid immunoreactivity in the immune system of lipopolysaccharide-stimulated mice
Authors: Espey Michael Graham , Moffett John Rodney , Namboodiri M A Aryan 
Published: January 2018

Abstract
Quinolinic acid (Quin), a metabolite of tryptophan, is a neurotoxin that has been implicated in a variety of neuropathologic disorders that have immune components. The goal of this study was to characterize the changes in the cellular localization of Quin immunoreactivity in a paradigm of immune stimulation with lipopolysaccharide (LPS) in vivo to provide a basis for further studies on the physiological role of Quin in the immune system. Intraperitoneal LPS injection significantly increased Quin immunoreactivity (IR) in lymphoid tissues within 24 h. Spatial changes in splenic Quin-IR demonstrated a shift from the periarterial lymphoid sheaths to the follicles before returning to control levels by 72 h post-LPS. The strongly Quin-IR cells were tentatively identified as interdigitating dendritic cells and macrophages. Only minimal Quin-IR was detected in liver and lung, even under conditions of LPS stimulation combined with tryptophan loading. These data emphasize the temporally and spatially specific nature of Quin-IR changes in lymphoid tissues under conditions of immune stimulation and raise the possibility that Quin may have an immunomodulatory function. J. Leukoc. Biol. 57: 199–206; 1995.
Effects of oxo and dihydro metabolites of 12-hydroxy-5,8,10,14-eicosatetraenoic acid on chemotaxis and cytosolic calcium levels in human neutrophils
Authors: Powell William S , Hashefi Mandana , Falck J R , Chauhan Kamlesh , Rokach Joshua , Wang Steven S , Mills Elaine , MacLeod R John 
Published: January 2018

Abstract
One of the pathways of metabolism of leukotriene B4 (LTB4) and 12-hydroxy-5,8,10,14-eicosatetraenoic acid (12-HETE) in leukocytes is oxidation of the 12-hydroxyl group, followed by reduction of the 10,11-double bond. In the case of 12R-HETE and 12S-HETE, this results in the formation of 12-oxo-ETE, 10,11-dihydro-12-oxo-ETE, and the 12R and 12S isomers of 10,11-dihydro-12-HETE (i.e., 12R-HETrE and 12S-HETrE). We investigated the effects of metabolites of 12-HETE formed by this pathway on cytosolic calcium levels and chemotaxis in human neutrophils. Of the above series of metabolites, 12S-HETrE (which has the same absolute stereochemistry at C-12 as 12R-HETE) was the most potent in stimulating both cytosolic calcium levels and chemotaxis. It was slightly less potent than 12R-HETE, consistent with the concept that reduction of the 10,11-double bond results in a loss of biological activity on neutrophils. The effect of 12S-HETrE on calcium levels was blocked by preincubation of these cells with LTB4, suggesting that it acted by stimulating the LTB4 receptor. 12R-HETrE was about 20 times less potent than its 12S isomer in stimulating cytosolic calcium in neutrophils and was also less active as a chemotactic agent. Oxidation of the 12-hydroxyl group to an oxo group resulted in a further loss of biological activity. 12-OxoETE, 8-trans-12-oxo-ETE, and 12-oxo-ETrE had only modest effects on cytosolic calcium levels at concentrations as high as 10 μM and did not display detectable chemotactic activity. However, 12-oxo-ETE and its 8-trans isomer inhibited calcium responses to LTB4 by about 40%. It is concluded that reduction of the 10,11-double bond of 12-HETE results in a slight loss of biological activity on neutrophils, whereas oxidation of the 12-hydroxyl group results in a considerably greater loss of activity. J. Leukoc. Biol. 57: 257–263; 1995.
Modulation of IL-8 receptor expression on purified human T lymphocytes is associated with changed chemotactic responses to IL-8
Authors: Xu Luoling , Kelvin David J , Ye George Q , Taub Dennis D , Ben-Baruch Adit , Oppenheim Joost J , Wang Ji Ming 
Published: January 2018

Abstract
Interleukin-8 is a member of the chemokine superfamily and is a major mediator of acute inflammation. Although IL-8 has been reported by some laboratories also to be a chemoattractant for T lymphocytes, this has been difficult to confirm and remains a controversial issue. By using freshly purified human T cells (90–95% CD3+), we could demonstrate consistent directional migration of T cells to recombinant human IL-8. IL-8 was as potent as RANTES, MIP1α, and M1P1β in inducing T cell chemotaxis. Highly purified T cells, however, incubated at 37° for more than 12 h or cultured over-night with anti-CD3 antibody cross-linked to plastic dishes, showed a markedly reduced capacity to migrate in response to IL-8. This was associated with a decrease in binding of radioiodinated IL-8 to T cells. Northern blot and polymerase chain reaction analyses showed that freshly purified T cells expressed mRNA for both IL-8 receptor type A and type B. Steady-state levels of mRNA for the IL-8RA and IL-8RB genes were also reduced by incubation of the cells with or without anti-CD3 for 12 h at 37°. These results indicate that T cells are indeed one of the target cell populations for IL-8. The regulation of IL-8 receptor expression on T lymphocytes may contribute to the pathophysiological role of IL-8 in inducing the homing and infiltration of T cells. J. Leukoc. Biol. 57: 335–342; 1995.