bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ultrastructural morphology of immature mast cells in sequential suspension cultures of human cord blood cells supplemented with c-kit ligand; distinction from mature basophilic leukocytes undergoing secretion in the same cultures
Authors: Dvorak Ann M , Mitsui Hideki , Ishizaka Teruko 
Published: January 2018

Abstract
The ability to culture human mast cells and, thus, to determine their ontogeny and possible relationships to other lineages has been facilitated by new studies using cocultures of cord blood cells with mouse fibroblasts and recombinant human or murine c-kit ligand- supplemented suspension cultures of cord blood cells. In this study, we examined c-kit ligand-supplemented cord blood cell suspension cultures designed so that the effects of growth factor source, individual cord sample, and culture time (3-17 weeks) on the developing mast cell lineage could be individually evaluated. We found that human mast cells, basophils, neutrophils, eosinophils, macrophages, megakaryocytes, and endothelial cells were present in these cultures. The numbers of mast cells and their granules increased with culture time; mature basophils, present in quantity in 3-week cultures, decreased in number and released granule contents with increased culture times. The mast cell lineage developed similarly, regardless of which factor preparation was added to cultures, but considerable variability existed among individual donors from whom cord bloods were obtained. Unlike the mature, crystal-containing mast cells that regularly developed in fibroblast cord blood cocultures (Furitsu et al. [1989] Proc. Natl. Acad. Sci. USA 86, 10039-10043), human mast cells failed to attain full maturity in the suspension cultures examined here, regardless of individual cord sample, added growth factor, or culture time. Furthermore, unlike cells of the basophil lineage in which granule content release was regularly observed, morphologic evidence of secretion from human mast cells was absent. Instead, these cells were actively undergoing granule building as determined by the increasing numbers of granules and filling of these containers over culture time. Crystal granules never developed, even at the maximum culture time of 17 weeks. We conclude that fibroblasts are necessary and sufficient for the differentiation and maturation of human mast cells in vitro from their agranular precursors in cord blood but that soluble c-kit ligand is not.
Selective inhibition of antigen-specific T lymphocyte proliferation by acute ethanol exposure: the role of impaired monocyte antigen presentation capacity and mediator production
Authors: Szabo Gyongyi , Verma Bikash , Catalano Donna 
Published: January 2018

Abstract
Ethanol consumption is associated with impaired immunity. Our data demonstrate that even a single dose of a biologically relevant concentration (25-150 mM) of ethanol can down-regulate antigen-specific T lymphocyte proliferation. In contrast, ethanol augmented mitogen-induced T cell proliferation, suggesting that its inhibitory effect on antigen-specific T cell proliferation was due to its effects on monocytes (mφs) rather than on T cells. The immunodepressive effects of ethanol on mφ antigen-presenting cell (APC) capacity were manifested whether alcohol treatment was limited to the antigen uptake-processing period only or was present during the entire period of antigen presentation. These inhibitory effects of ethanol were also evident on both the high- antigen-presenting, FcγRI-negative (-31 ± 17%), and low-antigen-presenting, FcγRI-positive (-42 ± 15%) mφ subpopulations. Further analysis demonstrated that ethanol inhibits the production of interleukin-1 β (IL-lβ) and induces transforming growth factor β (TGF-β) and prostaglandin E2 (PGE2), monocyte-derived mediators that can affect T cell proliferation. Ethanol resulted in a dose-dependent down-regulation of secreted and cell- associated IL-lβ protein as well as IL-lβ mRNA levels induced by adherence or bacterial stimulation. The causal relationship between decreased mφ IL-lβ production, elevated TGF-β levels, and the decreased mφ APC capacity was further substantiated when exogenous IL-lβ protein or anti-TGF-β neutralizing antibody prevented the down-regulatory effect of ethanol on antigen-specific T cell proliferation. Utilizing a cyclooxygenase inhibitor, we also demonstrated that the ethanol-induced decrease in mφ APCs is not mediated by enhanced PGE2 production.
Complement and tumor necrosis factor-α contribute to Mac-1 (CD11b/CD18) up-regulation and systemic neutrophil activation during endotoxemia in vivo
Authors: Witthaut Rochus , Farhood Anwar , Smith C Wayne , Jaeschke Hartmut 
Published: January 2018

Abstract
The increased expression of Mac-1 (CD11b/CD18) adhesion glycoproteins on neutrophils was studied using flow cytometry in male Fischer 344 rats treated with 5 mg/kg Salmonella cnteritidis endotoxin. A rapid and sustained threefold increase of Mac-1 expression was observed after endotoxin injection. Inhibition of complement activation with the soluble complement receptor type 1 (sCRl) completely suppressed the initial up-regulation of Mac-1 (≤ 15 min) but did not prevent the activation during the later phase (30–90 min). During that time period, Mac-1 expression increased in parallel with the concentration of tumor necrosis factor α (TNF-α) in plasma and could be significantly attenuated with TNF antiserum. To verify the results, isolated human neutrophils were incubated with rat plasma obtained at various times after endotoxin injection. Using shape change as indicator of neutrophil activation, complement and TNF-α could be identified as responsible mediators for neutrophil activation during endotoxemia in vivo. In contrast, the massive neutrophil accumulation in the liver after endotoxin was only slightly reduced by sCRl and unaffected by TNF antiserum. It is concluded that Mac-1 up-regulation on neutrophils after endotoxin injection in vivo may have limited relevance for hepatic neutrophil infiltration but may be important for the pathogenesis of endotoxin-induced liver injury by facilitating adherence-dependent neutrophil cytotoxicity. J. Leukoc. Biol. 55: 105–111; 1994.
Inhibition of crystal-induced neutrophil activation by a protein tyrosine kinase inhibitor
Authors: Burt Helen M , Jackson John K , Salari Hassan 
Published: January 2018

Abstract
The objective of this work was to investigate the role of tyrosine kinase in monosodium urate monohydrate (MSUM) and calcium pyrophosphate dihydrate (CPPD) crystal-induced neutrophil activation using the tyrosine kinase inhibitor lavendustin C (LVC). Human neutrophils pretreated with LVC at concentrations between 10 and 150 μM or control neutrophils were stimulated by plasma-coated CPPD or uncoated MSUM, and chemiluminescence, superoxide generation, intracellular calcium concentration, and degranulation (myeloperoxidase and lysozyme release) were monitored with time. LVC strongly inhibited chemiluminescence, superoxide anion generation, myeloperoxidase and lysozyme release, and calcium mobilization. After 1-min crystal-neutrophil incubations, neutrophil cytosolic fractions showed extensive inhibition of tyrosine kinase activity by LVC. We conclude that the inhibition of neutrophil responses to crystal stimulation, by the protein tyrosine kinase inhibitor LVC, provides evidence that supports the involvement of tyrosine kinases in crystal-induced neutrophil activation. J. Leukoc. Biol. 55: 112–119; 1994.
gp120 HIV envelope glycoprotein increases the production of nitric oxide in human monocyte-derived macrophages
Authors: Pietraforte Donatella , Tritarelli Elena , Testa Ugo , Minetti Maurizio 
Published: January 2018

Abstract
The effect of recombinant gp120 HIV envelope glycoprotein on the generation of free radicals by monocyte-derived macrophages (MDM) was measured by EPR spin trapping with 5,5 -dimethyl-1-pyrroline-N-oxide (DMPO). After 1 day in culture, MDM produced a spin trap adduct of DMPO with hyperfine splitting constants superimposable on those of DMPO-OH. The addition of gp120 to MDM increased the production of DMPO-OH and after 1 h, the amount of DMPO-OH produced by 40 μg/ml gp120 was about 300% that of untreated MDM. The use of selective inhibitors suggested the participation of the nitric oxide/l-arginine oxidative pathway, but did not provide evidence for trapping of hydroxyl radical or other oxygen free radicals. The specificity of gp120 was proven by two different anti-gp120 antibodies that either in-hibited (polyclonal) or increased (monoclonal) the production of free radicals. Dexamethasone inhibited the effect of gp120, suggesting the possible involvement of an inducible nitric oxide (NO·) synthase. Moreover, treatment of MDM with gp120 for 15 h increased in a dose-dependent manner the production of NO2-, a stable end product of NO·. Soluble CD4 did not modify the intensity of the DMPO-OH adduct, whereas yeast mannan and Ca2+-chelators abolished the increase in the DMPO-OH signal induced by gp120. These data suggest the possible involvement of mannose-specific endocytotic lectin of MDM. The reaction of DMPO with sodium nitroprusside, an organic nitrate that releases NO·, also produced DMPO-OH. Our findings indicate that gpl20 increases free radical production from MDM as detected by spin-trapping methods, and that the spin trap adduct results from a reaction involving NO· or closely related oxidized derivatives. J. Leukoc. Biol. 55: 175–182; 1994.
Comparison of leukotriene B4 and D4 effects on human eosinophil and neutrophil motility in vitro
Authors: Spada C S , Nieves A L , Krauss A H-P , Woodward D F 
Published: January 2018

Abstract
The motility of isolated normal human peripheral blood eosinophils and neutrophils in response to exogenous leukotrienes B4 and D4 was examined by means of a modified under-agarose technique and a novel quantitative sampling strategy. Leukotriene D4 was a potent chemoattractant for eosinophils, with a significant threshold chemotactic effect evident at 10-10 M. The abolition of eosinophil chemotaxis by the potent and selective peptide-leukotriene-antagonist SK&F 104353 indicated the pharmacological specificity of the leukotriene D4-induced response. The chemokinetic response of eosinophils to leukotriene D4 generally did not differ significantly from spontaneous migratory activity of unstimulated cells. Leukotriene D4 did not, however, alter directed neutrophil motility until a very high concentration (10-5 M) was achieved, although significant neutrophil chemokinesis relative to unstimulated movement was observed over the tested concentration range. Directional emigration of both eosinophils and neutrophils was induced by leukotriene B4 at concentrations as low as 10-8 M. Analysis of leukocyte orientations provided evidence that chemokinetic responses were not being interpreted as indications of chemotactic behavior. These studies suggest that leukotriene D4 may behave as a potent and selective chemoattractant for human eosinophils at physiologically relevant concentrations. J. Leukoc. Biol. 55: 183–191; 1994.
Cytokine induction in mice by the immunomodulator imiquimod
Authors: Reiter Michael J , Tester man Traci L , Miller Richard L , Weeks Charles E , Tomai Mark A 
Published: January 2018

Abstract
Imiquimod has been identified as a potent antiviral and antitumor agent in animal models. The biological activity associated with imiquimod has been attributed to its induction of interferon (IFN)-α. The present studies evaluated imiquimod administered orally for its ability to stimulate production of IFN and other cytokines in mice. The cytokine profile induced by imiquimod was compared with other known immunomodulators. Imiquimod was found to stimulate increased serum IFN in mice. Daily dosing of imiquimod for five consecutive days led to diminished production of IFN in mice as measured after the final dose. Elevated levels of serum tumor necrosis factor (TNF)-α and interleukin (IL)-6· but not IL-1α were found in serum from mice treated with imiquimod. Imiquimod produced significantly higher levels of IFN but lower levels of TNF and IL-6 and IL-1α than lipopolysaccharide. Polyinosinic acid:polycytidylic acid induced significantly higher amounts of IFN but lower levels of TNF and IL-6 than imiquimod. Imiquimod stimulated significantly higher levels of IFN when compared with 2-amino-5-bromo-6-phenyl-4(3H)-pyrimidi-none (ABPP) and similar levels of IFN when compared with tilorone. Neither ABPP nor tilorone induced TNF or IL-6. Finally, imiquimod stimulated TNF, IFN, and IL-6 production in cultures of mouse spleen and bone marrow cells. These studies demonstrate that imiquimod induces not only IFN but other cytokines as well, all of which may contribute to its biological activity. J. Leukoc. Biol. 55: 234–240; 1994.
The monoclonal antibody MAC387 detects an epitope on the calcium-binding protein MRP14
Authors: Goebeler Matthias , Roth Johannes , Teigelkamp Stefan , Sorg Clemens 
Published: January 2018

Abstract
The present study was initiated to identify the antigen recognized by the monoclonal antibody (MAb) MAC387 which is widely used for phenotypical characterization of myelomonocytic cells in situ. MAC387 has been described to show a similar reaction pattern as antisera to a complex formed by the calcium-binding proteins MRP8 and MRP14. However, the exact nature of the molecule recognized by MAC387 has been controversial. Using Western blot analysis, MAC387 was found to detect a single protein band of 14 kDa in lysates of human monocytes and granulocytes. Transfection of embryonic lung fibroblasts L132 with either MRP8 or MRP14 cDNA revealed that MAC387 reacts with MRP14 but not MRP8. This finding was confirmed by dot blot analysis of recombinant MRP8 and MRP14. Our data thus provide unequivocal evidence that MAC387 is a monoclonal antibody directed against the calcium-binding protein MRP14. J. Leukoc. Biol. 55: 259–261; 1994.
The role of tyrosine kinases and phosphotyrosine-containing recognition motifs in regulation of the T cell-antigen receptor-mediated signal transduction pathway
Authors: Isakov Noah , Wange Ronald L , Samelson Lawrence E 
Published: January 2018

Abstract
T cell-mediated immune responses are initiated by interaction of antigen bound to a glycoprotein encoded by the major histocompatibility complex with the T cell antigen receptor (TCR). These recognition and binding steps are followed by multiple intracellular biochemical events. The earliest event detected is an increase in intracellular protein tyrosine phosphorylation that involves a complex interaction of tyrosine kinases and phosphatases. Subsequently, one observes an increase in protein serine/threonine phosphorylation, phospholipid hydrolysis, and changes in intracellular Ca2+ levels. These and other biochemical changes lead to cell proliferation, differentiation, and acquisition of effector functions. While binding of extracellular growth factors to receptors containing cytoplasmic protein tyrosine kinase (PTK) domains induces direct activation of their kinase activity, the multichain TCR lacks an intrinsic kinase domain and therefore represents a distinct type of receptor. It transduces signals via the interaction with, and activation of, non-receptor PTKs. Recent efforts directed at defining the TCR-linked signaling pathways have provided insight into the regulatory role of three PTKs, and the functional importance of some unique protein motifs in both TCR subunits and PTKs, which mediate critical protein-protein interactions in this pathway. J. Leukoc. Biol. 55: 265–271; 1994.
Inhibitory effect of a dendritic epidermal T cell line on K1735 melanoma cells in vivo and in vitro
Authors: Love-Schimenti Cheryl D , Kripke Margaret L 
Published: January 2018

Abstract
Murine epidermis contains a resident population of dendritic epidermal T cells (DETCs) with unknown function. We tested the ability of a cultured line of these cells to inhibit the growth of murine melanoma cells in vitro and in vivo. The interleukin-2 (IL-2)-dependent T cell line AU16, derived from the epidermis of C3H mice, was used as the source of DETCs. AU16 cells were cytotoxic to syngeneic K1735 and CM3205 C3H melanoma cell lines, as well as to a chemically induced cutaneous fibrosarcoma, in an in vitro 51Cr release assay. Mixing viable AU16 cells, but not splenic T cells, with K1735 melanoma cells immediately before intradermal injection into the flank of mice prevented or delayed the outgrowth of melanomas. AU16 cells killed by freezing and thawing and supernatants from cultures of AU16 cells did not inhibit melanoma growth in vivo or in vitro. Injection of viable AU16 cells intravenously or at a separate intradermal site had no effect on melanoma growth. These studies suggest that IL-2-activated DETCs have the potential to inhibit the growth of melanoma cells in vivo and that their cytotoxic activity may be responsible for this effect. J. Leukoc. Biol. 55: 379–384; 1994.
Histaminergic regulation of antibody-dependent cellular cytotoxicity of granulocytes, monocytes, and natural killer cells
Authors: Hellstrand Kristoffer , Asea Alexander , Hermodsson Svante 
Published: January 2018

Abstract
We investigated effects of the biogenic diamine histamine on antibody-dependent cellular cytotoxicity (ADCC) against autologous anti-D-coated red blood cells mediated by human granulocytes, monocytes, and natural killer (NK) cells. Effector cells were separated from peripheral blood by countercurrent centrifugal elutriation. ADCC of monocytes and neutrophilic granulocytes was suppressed by histamine. ADCC of enriched CD3-/56+ NK cells was unchanged by histamine. ADCC of NK cells was effectively inhibited by elutriated monocytes or neutrophils. Histamine completely reversed the inhibition of NK cell-mediated ADCC induced by monocytes and partly reversed the inhibition induced by neutrophils; thereby, histamine augmented ADCC of NK cells in the presence of monocytes or neutrophils. The indirect effect of histamine on ADCC of NK cells and the effect of histamine on ADCC of monocytes/neutrophils were completely antagonized by the specific H2 receptor (H2R) blocker ranitidine. We conclude that activation of H2R suppresses ADCC reactivity of monocytes/neutrophils and, concomitantly, promotes ADCC reactivity of NK cells by abrogating a phagocyte-derived, suppressive signal. J. Leukoc. Biol. 55: 392–397; 1994.
Selective regulation of human neutrophil functions by the cell activation inhibitor CI-959
Authors: Wright Clifford D , Stewart Sheila F , Kuipers Paul J , Hoffman Michael D , Devall Larry J , Kennedy John A , Ferin Mark A , Thueson David O , Conroy Mary Carol 
Published: January 2018

Abstract
The cell activation inhibitor CI-959 [5-methoxy-3-(1-methylethoxy)-N-1H-tetrazol-5-ylbenzo[b]thiophene-2-carboxamide, monosodium salt] was evaluated for its effects on human neutrophil functions. CI-959 inhibited spontaneous migration and chemotaxis toward N-formyl–methionyl-l-leucyl-l-phenylalanine (fMLP) with 50% inhibition (IC50) values of 3.6 and 3.1 μM, respectively. CI-959 also inhibited superoxide anion generation in response to C5a, fMLP, serum-opsonized zymosan (SOZ), concanavalin A (Con A), and calcium ionophore A23187 with IC50 values of 2.5, 4.7, 14.5, 5.4, and 14.8 μM, respectively. In comparison, CI-959 inhibited myeloperoxidase release in response to C5a, fMLP, SOZ, and Con A with IC50 values of 11.6, 16.1, 7.5, and &lt;1.0 μM, respectively, while inhibiting the response to A23187 by only 5.5% at 100 μM. At concentrations up to 100 μM, CI-959 had no effect on the respiratory burst or degranulation in response to L-α-1,2-dioctanoylglycerol (DiC8) or phorbol 12-myristate 13-acetate (PMA). In addition, the compound inhibited leukotriene B4 release stimulated by fMLP and SOZ (IC50 values 4.0 and 2.5 μM, respectively), while having less activity against the A23187-stimulated response (IC50&gt;100 μM). These results demonstrate that CI-959 inhibits cellular responses to stimuli that mobilize intracellular calcium. For cellular responses to ionophore-mediated calcium influx, only oxygen radical production was inhibited by CI-959. CI-959 was further evaluated for its effects on neutrophil stimulus-response coupling. At 100 μM, CI-959 had no effect on human neutrophil phospholipase C or protein kinase C. CI-959 inhibited fMLP-stimulated intracellular calcium mobilization and calcium influx with IC50 values of 16.7 and 3.1 μM, respectively, and exhibited less potent calmodulin antagonist activity (IC50 = 90.5 μM). These results indicate that CI-959 may exert its stimulus- and response-specific inhibitory effects on neutrophil functions, in part, through inhibition of calcium-regulated signalling mechanisms. J. Leukoc. Biol. 55: 443–451; 1994.
Serum components enhance bacterial lipopolysaccharide-induced tissue factor expression and tumor necrosis factor-α secretion by bovine alveolar macrophages in vitro
Authors: Yang Zhengang , Khemlani Lajwanti S , Dean David F , Carter Candace D , Slauson David O , Bochsler Philip N 
Published: January 2018

Abstract
We have compared the effect of bacterial lipopolysaccharide (LPS) in combination with normal adult bovine serum (NBS), fetal bovine serum (FBS), or a bovine serum fraction on tissue factor expression and tumor necrosis factor α (TNF-α) secretion by bovine alveolar macrophages. At a concentration of 1 ng/ml, bacterial LPS alone failed to induce measurable tissue factor expression by the macrophages, but the presence of FBS, NBS, or a fraction of normal pooled bovine serum isolated by ion-exchange chromatography (fraction 2) markedly potentiated the effect of LPS. A protein concentration of 64 μg/ml NBS, 192 μg/ml FBS, and only 640 ng/ml fraction 2 was required to induce maximal tissue factor expression on the macrophages in combination with 1 ng/ml LPS. Comparison of quantities of added serum protein required to induce maximal potentiating effects indicated that fraction 2 was 100 times more potent than1 whole NBS and 300 times more potent than whole FBS. We similarly found that TNF-α secretion by macrophages exposed to LPS was responsive to serum and was highly responsive to fraction 2. LPS alone (1 ng/ml) induced a relatively low level of TNF-α secretion by the macrophages, and the presence of FBS, NBS, or fraction 2 potentiated the effect of LPS. A concentration of 64.0 μg/ml NBS, 320.0 μg/ml FBS, and 3.2 μg/ml fraction 2 serum protein induced near-maximal TNF-α secretion by the macrophages. Comparison of the concentration of serum protein required to induce these potentiating effects indicated that fraction 2 was approximately 20 times more potent than whole NBS and 100 times more potent than whole FBS. The stimulatory effect of LPS plus fraction 2 serum proteins was dependent on the CD14 receptor, as monoclonal antibodies directed against CD14 (My4, 60bd; 10 μg/ml) inhibited tissue factor expression and TNF-α secretion by the macrophages. J. Leukoc. Biol. 55: 483–488; 1994.