bluuebunny/crossref_metadata_2025_split huggingface dataset:
Steroidal nonspecific esterase metabolism of N-hydroxy-2-acetylaminofluorene: evidence for selective activation by the cellular reductant NADPH
Authors: Lund-Pero Margaretha , Pero Ronald W , Miller Daniel G 
Published: January 2018

Abstract
The significance of the nonspecific esterases of human mononuclear leukocytes (HMLs) in arylamine carcinogenesis is suggested by data showing that the metabolically formed hydroxamic acid derivative of 2-acetylaminofluorene, N-hydroxy-2-acetylaminofluorene, is a substrate for this class of enzymes. A viable cell assay for the nonspecific esterases using α-naphthyl acetate as substrate is described, and data showing this activity to be sensitive to already known substrates for HML esterases as measured by three previously described assays are presented. All four assays of the same esterase activity are shown to be highly sensitive to up- and down-regulation by addition of NADPH or NADP to viable HML cultures. Selective activation of a purified rabbit nonspecific esterase by NADPH, but not by the other cellular reductants, NADH and glutathione, was demonstrated. Cytosols prepared from normal human tissue samples of liver, breast, colon, and brain were also activated by the presence of NADPH. These data do not indicate that steroidal nonspecific esterases are redox-modulated by the presence of mixed disulfides in their structure. Instead, they support the direct and specific influence of NADPH as a widespread activator of esterase activity by a mechanism not yet understood.
Ovine mononuclear phagocytes in situ: identification by monoclonal antibodies and involvement in experimental pyogranulomas
Authors: Pepin Michel , Cannella Dominique , Fontaine Jean-Jacques , Pittet Jean-Christophe , Le Pape Alain 
Published: January 2018

Abstract
In order to characterize in situ the macrophages present in experimental pyogranulomas induced in lambs with Corynebacterium pseudotuberculosis, a set of monoclonal antibodies (MAbs) was produced following immunization of BALB/c mice with alveolar macrophages from healthy sheep. Three MAbs were retained after two steps of screening using alveolar macrophages, peripheral blood lymphocytes, and polymorphonuclear leukocytes as target cells. Their reactivity was tested not only on macrophages in pyogranulomas but also on sections of various organs in steady-state conditions. One MAb, termed OM1, recognized the monocytes and the majority of cells of the mononuclear phagocyte system in lymphoid and nonlymphoid organs. The two other MAbs, OM2 and OM3, reacted with a subpopulation of alveolar macrophages and with other cell types in tissues, in particular with endothelial cells for the MAb OM2. On sections of experimental pyogranulomas that developed in lymph nodes draining the C. pseudotuberculosis-injected sites, MAb OM1 reacted with all the macrophages distributed in a palisade surrounding the necrotic center of the lesion from day 6 to day 28 postinoculation. The two other MAbs, OM2 and OM3, enabled two types of granulomas to be distinguished: one type was characterized by a large number of epithelioid cells stained by OM2; and the other was characterized by a few OM2-positive macrophages, whereas the OM3-positive cells were more numerous. These results show that macrophages are predominant cells in pyogranulomas and suggest two different histological patterns in the evolution of pyogranulomas induced by C. pseudotuberculosis, according to the immunological status of the host.
Effect of adenosine analogues and cAMP-raising agents on TNF-, GM-CSF–, and chemotactic peptide–induced degranulation in single adherent neutrophils
Authors: Richter Johan 
Published: January 2018

Abstract
Adenosine and adenosine analogues are potent inhibitors of the respiratory burst in neutrophils. Most investigators, however, have found little or no effect of these compounds on neutrophil degranulation from cytochalasin B–treated neutrophils in suspension. We have instead investigated the effect of adenosine and 2-chloroadenosine on degranulation in adherent neutrophils in the absence of cytochalasin B. Both adenosine and 2-chloroadenosine were effective inhibitors of lactoferrin secretion induced by the chemotactic peptide N-formyl-methionine-leucyl-phenylalanine (fMLP) [50% inhibitory concentration (IC50) of less than 10-6 M]. Secretion induced by tumor necrosis factor (TNF) or granulocyte-macrophage colony-stimulating factor (GM-CSF) was inhibited only at high concentrations (IC50 of approximately 10-4 M). In the presence of cytochalasin B no inhibitory effect of 2-chloroadenosine was seen. The effect of cAMP-raising agents on secretion from adherent neutrophils was also investigated. Dibutyryl cAMP at 0.2 mM reduced secretion in response to fMLP by 50% but did not inhibit TNF- and GM-CSF-induced degranulation. At a concentration of 2.0 mM dibutyryl cAMP also inhibited exocytosis in response to the two cytokines. The phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (IBMX) at 300 μM reduced fMLP-induced degranulation, whereas a concentration of 1 mM was required to inhibit TNF- and GM-CSF-mediated secretion. The adenylate cyclase activator forskolin (50 μM) alone did not inhibit secretion in response to TNF or fMLP. However, in combination with IBMX (300 μM), forskolin (50 μM) reduced both TNF- and fMLP-induced secretion to less than 10%. PMA-induced exocytosis was unaffected by all these agents. In conclusion, adenosine appears to be an effective inhibitor of neutrophil granule protein secretion induced by fMLP but only a weak inhibitor of exocytosis in response to TNF or GM-CSF. Secretion in response to fMLP was also found to be more susceptible to a rise in cAMP than degranulation induced by TNF and GM-CSF.
In vitro development of lymphocytes that function as progenitors for mucus-secreting lymphokine-activated killer (LAK) cells
Authors: Ginsburg Haim 
Published: January 2018

Abstract
Two different types of cultures developed when two different interleukin 2 (IL-2) preparations were introduced into cultures of lymph node cells of nulnu (nude) mice maintained on an embryonic fibroblast monolayer. In the first, human recombinant IL-2 (rIL-2) stimulated the generation of colonies of large cytotoxic cells identified as lymphokine-activated killer (LAK) cells that, when grown on mesenchyme fibroblastoid monolayers prepared from 16- to 18-day embryos, could be triggered to synthesize and secrete flowing mucoid material. In the second culture, crude supernatant from cultures of rat spleen cells stimulated by concanavalin A stimulated the appearance and multiplication of blast cells that, after 20 days, differentiated into lymphocytes. This population was homogeneously composed of “wandering” lymphocytes and could be kept in a stable resting form for at least 2 months without loss of viability. When exposed to rIL-2, this whole lymphocyte population underwent a transformation into blast cells that, on the fourth day, generated granules, became cytotoxic, and differentiated into granular mucus-secreting LAK cells. When low numbers of these transformed premitotic blast cells were plated on mitomycin C-treated embryonic fibroblast monolayers, one cell out of 15 to 20 generated a clone of LAK cells. The study demonstrates that both effector and “memory” arms of differentiation can be stimulated in vitro.
Detection and analysis of the 80-kd lipopolysaccharide receptor in macrophages derived from Lpsn and Lpsd mice
Authors: Perera Pin Yu , Chen Tai-Ying , Morrison David C , Vogel Stefanie N 
Published: January 2018

Abstract
An 80-kd lipopolysaccharide (LPS)-binding protein with specificity for the lipid A region has been identified on lymphocyte and macrophage membranes. In an attempt to gain insight into the hyporesponsiveness of C3H/HeJ (Lpsd) mice to LPS, an affinity-purified rabbit polyclonal IgG with specificity for this receptor was used to compare the expression and distribution of the 80-kd LPS receptor on thioglycollate-elicited peritoneal macrophages derived from normal (Lpsn) and (Lpsd) mice. By enzyme-linked immunosorbent assay, immunofluorescence microscopy, and flow cytometry, macrophages from Lpsn and Lpsd mice showed comparable expression of the 80-kd LPS receptor, although only a subpopulation of macrophages from both strains express it. Macrophages from both strains showed indistinguishable surface distribution of the 80-kd LPS receptor, as determined by confocal microscopy and analysis using an anchored cell analysis station. Treatment of macrophages with interferons, protein-rich LPS, or glucocorticoids, agents known to modulate a variety of macrophage cell surface markers and receptors, failed to alter expression of the 80-kd receptor. These findings support the hypothesis that the hyporesponsiveness of the Lpsd mouse strains to LPS is not due to an absence of receptors but rather is distal to binding of LPS and most likely attributable to a failure of these macrophages to transduce the signal derived at the cell surface to the interior of the cell.
Characterization and use of monoclonal and polyclonal antibodies against the mouse interferon-γ receptor
Authors: LeClaire Ross D , Basil Mitali , Pinson David M , Redick Mark L , Hunt Joan S , Zavodny Paul J , Pace Judith L , Russell Stephen W 
Published: January 2018

Abstract
To facilitate investigation of its physical and functional properties, 11 monoclonal antibodies (mAbs) and a goat polyclonal IgG specific for the mouse interferon- (IFN-γ) receptor were characterized and their potential uses studied. Eight of the mAbs interacted with epitopes on the extracellular domain of the receptor, two interacted with epitopes on the intracellular domain, and one interacted with an epitope that could not be localized definitively to either region. Of the 11 mAbs, the majority (8) were IgGs, 2 were IgMs, and 1 was an IgA. Relative avidities of the seven that could be determined ranged from 333 to 0.002 μM-1. Both the polyclonal goat IgG and mAb GR-20 (the latter specific for an epitope in the binding site for IFN-γ) blocked binding of the ligand and, as expected, prevented induction by IFN-γ of priming of macrophages for tumor cell killing. None of the other mAbs had an effect despite the fact that GR-22 partially (&gt; 50%) blocked binding of IFN-γ. Neither the polyclonal IgG nor any of the mAbs had an agonist effect. The relative usefulness of the antibodies for immunoprecipitation, immunoblotting, immunoassay, and cell staining with and without prior fixation is described. The results of immunocytochemical staining directly confirmed that the majority of immunologically reactive receptor protein expressed by cells is intracellular. To facilitate use by other investigators, the hybridomas that produce these mAbs will be offered to the American Type Culture Collection.
Culture of ovine bone marrow–derived macrophages and evidence for serum factors distinct from M-CSF contributing to their propagation in vitro
Authors: Francey T , Jungi TW , Rey O , Peterhans E 
Published: January 2018

Abstract
An in vitro system allowing the culture of ovine bone marrow–derived macrophages (BMMs) is described. Bone marrow (BM) cells from the sternum of 4-to 9-month-old sheep were cultured in liquid suspension in hydrophobic bags with medium containing 20% autologous serum and 20% fetal calf serum (FCS). Cells with macrophage characteristics were positively selected and increased four- to fivefold between day (d) 0 and d18. Granulocytes and cells of lymphoid appearance including progenitor cells were negatively selected and were diminished 50-fold during this 18-d culture. The addition of macrophage colony-stimulating factor (M-CSF)–containing supernatants to liquid cultures did not significantly improve the yield of BMM in 18-d cultures. In contrast, cell survival at d6 and macrophage cell yield at d18 depended on the concentration and source of serum in the culture medium. FCS and 1:1 mixtures of FCS and autologous serum were superior to autologous serum alone. Analysis of growth requirements of ovine BMMs suggested that they are under more complex growth control than their murine counterparts. In an [3H]thymidine incorporation assay with BM cells collected at different times of culture, d3 or d4 BM cells responded to human recombinant M-CSF, human recombinant granulocyte-macrophage colony-stimulating factor (GM-CSF), bovine GM-CSF, murine M-CSF or murine M-CSF-containing supernatants, and bovine interleukin 1β (IL-1β) in decreasing order of magnitude. Likewise, pure murine BMM populations harvested at d6 responded to homologous GM-CSF, IL-3, and human or murine M-CSF. FCS did not stimulate the proliferation of murine BMMs (d6) and of ovine BM cells (d3 or d4). In contrast, ovine BM cells harvested at d12 responded to FCS by proliferation in a dose-dependent manner but failed to proliferate in the presence of human or murine M-CSF or M-CSF-containing supernatants of mouse and sheep fibroblasts containing mouse macrophage growth-promoting activity. Likewise, various cytokine-containing supernatants and recombinant cytokines (murine IL-3, murine and human GM-CSF, murine and bovine IL-1β) did not promote proliferation of ovine d12 BM cells to an extent greater than that achieved with 15% FCS alone. Thus, ovine BMM proliferation is under the control of at least two factors acting in sequence, M-CSF and an unidentified factor contained in FCS. The ovine BMM culture system may provide a model for the analysis of myelomonocytopoiesis in vitro.
Ultrastructural identification of human mast cells resembling skin mast cells stimulated to develop in long-term human cord blood mononuclear cells cultured with 3T3 murine skin fibroblasts
Authors: Dvorak Ann M , Furitsu Takuma , Kissell-Rainville Susan , Lshizaka Teruko 
Published: January 2018

Abstract
Human mast cells developed in vitro when cord blood mononuclear cells were cocultured for 3 months with 3T3 embryonic mouse skin fibroblasts. The metachromatic cells that arose in these cultures contained histamine, a functional Fcε receptor and granule proteases (tryptase, chymase), and they were definitively identified by the ultrastructural demonstration of crystal granules. We present a detailed ultrastructural analysis of this newly available system for the reliable development of human mast cells in vitro and provide criteria for definitive identification of the mast cell and basophil lineages in humans.
Defective lipopolysaccharide-induced production of both interleukin 1α and interleukin 1β by A/J mouse macrophages is posttranscriptionally regulated
Authors: Brandwein Sydney R , Maenz Lynn 
Published: January 2018

Abstract
Interleukin 1 (IL-1) production by A/J (A) and C57BL/6J (B6) mouse peritoneal macrophages stimulated with lipopolysaccharide (LPS) was determined. Strain A macrophages produced low levels of soluble IL-1 bioactivity compared with B6 macrophages. This defect was not reversed by indomethacin, interferon-γ, phorbol myristate acetate, or calcium ionophore A23187. In contrast, cytosolic IL-1 bioactivity was similar in LPS-stimulated A and B6 macrophages. Western blotting revealed that A macrophage supernatants contained lower levels of both 17-kd IL-1α and 17-kd IL-1β but similar levels of tumor necrosis factor α compared with B6 macrophages. Cytosolic levels of 31-kd Pro-IL-1α and also 31-kd pro-IL-1β were similar in A and 6 macrophages. Oligonucleotide probing indicated that A and B6 macrophages contained similar levels of IL-1α and also IL-1β mRNA. These findings indicate that LPS-stimulated A macrophage culture supernatants contain low levels of both IL-1α and IL-1β compared with B6 macrophages and that these defects in IL-1 production are posttranscriptionally regulated.
Cytokine secretion by immune cells in space
Authors: Chapes Stephen K , Morrison Dennis R , Guikema James A , Lewis Marian L , Spooner Brian S 
Published: January 2018

Abstract
Cultured, bone marrow–derived macrophages, murine spleen and lymph node cells, and human lymphocytes were tested for their ability to secrete cytokines in space. Lipopolysaccharide-activated bone marrow macrophages were found to secrete significantly more interleukin-1 and tumor necrosis factor when stimulated in space than when stimulated on earth. Murine spleen cells stimulated with poly I:C in space released significantly more interferon-α at 1 and 14 hours after stimulation than cells stimulated on earth. Similarly, murine lymph node T cells and human peripheral blood lymphocytes, stimulated with concanavalin A in space, secreted significantly more interferon-γ than ground controls. These data suggest that space flight has a significant enhancing effect on immune cell release of cytokines in vitro.
Interleukin-8 induces changes in human neutrophil actin conformation and distribution: relationship to inhibition of adhesion to cytokine-activated endothelium
Authors: Westlin William F , Kiely Jeanne-Marie , Gimbrone Michael A 
Published: January 2018

Abstract
Interleukin-8 (IL-8) induces diverse biological responses in neutrophils, including inhibition of adhesion to cytokine-activated endothelium, which we have termed the leukocyte adhesion inhibition (LAI) effect. Pretreatment of neutrophils with cytochalasin B abolished the LAI effect of IL-8, suggesting a microfilament-dependent mechanism. Interleukin-8 induced a rapid increase (≤ 15 s) in the polymerization of actin filaments in human neutrophils that was blocked by pretreatment with cytochalasin B. F-actin depolymerization occurred gradually at a rate inversely proportional to IL-8 concentration. This temporal pattern of actin polymerization-depolymerization was similar to that induced by other chemotactic factors such as C5a and N-formylmethionyl-leucyl-phenylalanine, which also exhibit a marked LAI effect, but the lipid mediators, leu-kotriene B4 and platelet-activating factor, lack any significant LAI effect. Scanning confocal microscopy demonstrated that neutrophil actin microfilaments undergo a dramatic rearrangement prior to detachment of the neutrophil from a surface. We suggest that the ability of IL-8 and certain other leukocyte agonists to regulate the actin polymer network of neutrophils may play an important role in adhesive interactions with the vascular endothelium.
Low response of BALB/c macrophages to priming and activating signals
Authors: Oswald Isabelle P , Afroun Samia , Bray Dorothy , Petit Jean-François , Lemaire Genevieve 
Published: January 2018

Abstract
Trehalose dimycolate (TDM), a mycobacterial glycolipid, is a powerful macrophage-priming agent. However, its efficiency seems limited in the case of BALB/c mice. Peritoneal macrophages harvested from TDM-treated BALB/c mice did not control BCG growth in vitro as efficiently as similar macrophages from two other mouse strains, (B6 × D2)F1 and C57BL/6, which are respectively Bcgr and Bcgs. BALB/c macrophages elicited by TDM also exhibited a low capacity to produce hydrogen peroxide and, after activation by lipopolysaccharide (LPS), weak cytostatic activity against P815 mastocytoma cells. Finally, alkaline phosphodiesterase, a marker of resident and inflammatory macrophages, was still expressed at a high level in macrophages of BALB/c mice treated with TDM. Low responsiveness of BALB/c macrophages to stimuli was not observed with TDM only; activation for tumor cytotoxicity of thioglycolateelicited macrophages from BALB/c mice required also higher doses of interferon-γ, and LPS. l-Arginine–dependent production of nitric oxide was inducible in macrophages from BALB/c mice, but the conditions required for its induction were more stringent. Thus, the reduced antiproliferative effects of BALB/c macrophages may be due to uncomplete induction of NO synthase after suboptimal stimulation.
Activation of bovine neutrophils by Pasteurella haemolytica leukotoxin is calcium dependent
Authors: Ortiz-Carranza O , Czuprynski CJ 
Published: January 2018

Abstract
In this study, we used the fluorescent probe Fluo-3 to show that an increase in cytosolic free calcium, [Ca2+]i, occurred when suspensions of bovine neutrophils were incubated with sublethal concentrations of P. haemolytica leukotoxin. This increase in [Ca2+]i was dependent on the concentration of leukotoxin present in the medium and, at a given concentration of leukotoxin, dependent on the external calcium concentration. The calcium channel blocker verapamil and the β-adrenergic antagonist propranolol inhibited leukotoxin-stimulated Ca2+ gain, as did a neutralizing antileukotoxin monoclonal antibody. As reported previously, incubation of bovine neutrophils with partially purified leukotoxin stimulated a vigorous luminol-dependent chemiluminescence response (LDCL). The present study shows that LDCL stimulation was dependent on the presence of extracellular calcium and was inhibited by the addition of verapamil and propranolol. These data indicate that bovine neutrophils exhibit a considerable increase in cytoplasmic free calcium when they are incubated with P. haemolytica leukotoxin in the presence of external calcium. They also provide evidence that an increased [Ca2+]i is required for functional activation of the bovine neutrophil oxidative burst by P. haemolytica leukotoxin.
Cytokines and suppressor macrophages cause tumor-bearing host CD8+ T cells to suppress recognition of allogeneic and syngeneic MHC class II molecules
Authors: Walker Thomas M , Yurochko Andrew D , Burger Carol J , Elgert Klaus D 
Published: January 2018

Abstract
Quantitative and qualitative tumor-associated changes in T cell phenotype and function were identified in CD8+ T cells. Tumor growth changed splenic CD4+/ CD8+ T cell ratios and induced the appearance of more cells with the CD8+ phenotype. In comparison to equal concentrations of normal host (NH) counterparts, tumor- bearing host (TBH) CD8+ T cells were highly suppressive to allorecognition and autorecognition. Suppression was not due to quantitative reductions in CD4+ T cells, although minor qualitative differences were observed. Suppression appeared to be mediated partly by prostaglandin E2 (PGE2). Interferon-γ (IFN-γ) and interleukin-4 (IL-4) contributed to TBH CD8+ T cell-mediated suppression. Blocking studies using monoclonal antibodies (mAb) in conjunction with indomethacin suggested that cytokine networks involving IFN-7, IL-4, and PGE2 were disrupted during tumor growth and promoted TBH CD8′+' T cell suppression. Alloresponses and autoresponses were significantly suppressed when TBH CD8+ T cells mediated these reactions simultaneously with TBH la” macrophages. Inhibition of PGE2 production was unable to reverse the additive suppression caused by these two cell types. These results collectively suggest that tumor- induced changes in CD8+ T cells lead to suppressed allorecognition and autorecognition through both soluble mediator molecules and cellular interactions.