bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thrombopoietin enhances neutrophil production by bone marrow hematopoietic progenitors with the aid of stem cell factor in congenital neutropenia
Authors: Sawai Nobukuni , Koike Kenichi , Mwamtemi Hadija Hemed , Ito Susumu , Kurokawa Yumi , Sakashita Kazuo , Kinoshita Tatsuya , Higuchi Tsukasa , Takeuchi Kouichi , Shiohara Masaaki , Kamijo Takehiko , Higuchi Yumiko , Miyazaki Hiroshi , Kato Takashi , Kobayashi Masao , Miyake Munenori , Yasui Kozo , Komiyama Atsushi 
Published: September 2022

Abstract
We examined the effects of granulocyte colony-stimulating factor (G-CSF), stem cell factor (SCF), and thrombopoietin (TPO), alone or in combination, on the generation of neutrophils by bone marrow (BM) cells from three patients with severe congenital neutropenia (SCN) through the use of a serum-deprived liquid culture system. Synergistic effects of G-CSF and SCF on the neutrophil production by BM CD34+CD38+c-kit+ cells were observed in SCN patients as well as in normal controls. The addition of TPO to the culture containing G-CSF and SCF further augmented the growth of neutrophils in the two groups. Single-cell culture experiments revealed that the three-factor combination caused increases in both the number and size of neutrophil colonies compared with G-CSF + SCF in normal BM cells, whereas only a significant increment in the colony size was observed in SCN patients. Even in the presence of SCF or SCF + TPO, the concentrations of G-CSF necessary for the substantial production of neutrophils by CD34+CD38+c-kit+ cells were higher in two patients compared with the levels obtained by normal control cells. In addition, TPO did not accelerate the maturation of neutrophilic cells supported by G-CSF + SCF. When BM CD34+CD38−c-kit+ cells were targeted, the addition of TPO to the culture containing G-CSF and SCF was required for significant neutrophil colony growth in the two groups. These results suggest that TPO enhances the G-CSF-dependent neutrophil production with the aid of SCF in this disorder.
HIV-1 replication in CD4+ T cell lines: the effects of adaptation on co-receptor use, tropism, and accessory gene function
Authors: Dejucq Nathalie 
Published: September 2022

Abstract
We studied the replication of HIV-1 macrophage-tropic CCR5-using strains (R5) in CD4+ T cell lines to better understand the switch in co-receptor use of such strains during disease progression and to assess resulting changes in cell tropism. We found that the majority of R5 strains cannot replicate in CD4+ T cell lines without adaptation by serial passage. A small minority of primary R5 isolates, however, were able to infect two T cell lines, Molt4 and SupT1. This expanded tropism was due to the use of undetectable levels of CCR5 rather than CXCR4 or alternative receptors. In contrast, HIV-1SF162 adaptation for replication in the C8166 T cell line was due to the emergence of variant strains that could use CXCR4. Of two variants, one was dual-tropic and one T-tropic, although both could use CCR5 as well as CXCR4. A single mutation in the start codon of the accessory gene vpu accounted for the T-tropic phenotype of the second variant, indicating that a non-functional vpu impairs macrophage tropism. Thus, in vitro and in the absence of an immune response, R5 strains naturally adapt to infect CXCR4+ T cell lines. Such adaptation resembles the rare R5 to X4 switch that occurs in vivo. Mutations in accessory genes (e.g., vpu) not required for replication in rapidly dividing cell lines may also occur in vitro, abrogating replication in primary cell types such as macrophages. Such mutations, however, are normally selected against in vivo.
Proinflammatory response and IL-12 expression in HIV-1 infection
Authors: Ma Xiaojing , Montaner Luis J 
Published: September 2022

AbstractHIV-1 infection elicits a broad range of host responses, many of which interfere with the regulatory pathways of gene expression of interleukin-12 (IL-12), a heterodimeric cytokine essential for cell-mediated immunity against microbial infection. The inhibition of IL-12 production by accessory cells after HIV-1 infection has been identified as a potential factor responsible for impaired innate and Th1 cell-mediated responses observed in AIDS patients. The mechanism by which HIV-1 infection suppresses IL-12 gene expression is largely uncharacterized. Here we review all pathways identified that could potentially mediate HIV-induced impairment of IL-12 gene expression, such as IL-10, transforming growth factor β, interferon-α/β, tumor necrosis factor α, Fc receptors, complement regulatory proteins, and receptors. Also discussed is the decreased CD40 ligand induction in CD4 T cells during HIV infection, which may have a strong impact on T cell-dependent IL-12 production that is critical for the establishment and maintenance of a Th1 response.
Sequential migration of neutrophils across monolayers of endothelial and epithelial cells
Authors: Mul Frederik P J , Zuurbier Astrid E M , Janssen Hans , Calafat Jero , van Wetering Sandra , Hiemstra Pieter S , Roos Dirk , Hordijk Peter L 
Published: September 2022

AbstractIn the course of granulocyte-dominated lung inflammation, granulocytes migrate across the endothelium and epithelium of the lung and cause severe tissue damage. To study this process in more detail, we developed a bilayer transmigration model composed of primary human endothelial and lung epithelial cells, simultaneously cultured on opposite sides of Transwell filters. Electron microscopical analysis showed that the morphology of the cells and the expression of junctional proteins remained unaltered and that matrix components were deposited onto the filter. Intriguingly, neutrophil migration was more efficient across the bilayers than across single epithelial monolayers and did not differ from migration across single endothelial monolayers. Coculture experiments showed that endothelial cells stimulated epithelial cells to release IL-6 and that epithelial cells enhanced release of IL-8 from endothelial cells. Together these data reveal bidirectional signaling and enhanced neutrophil migration in a transmigration model of primary human epithelial and endothelial cells.
Clustering on the forward surfaces of migrating neutrophils of a novel GPI-anchored protein that may regulate neutrophil adherence and migration
Authors: Nakamura-Sato Yukiko , Sasaki Katsunori , Watanabe Hiroshi , Araki Yoshihiko , Sendo Fujiro 
Published: September 2022

Abstract
We previously reported a novel glycosylphosphatidylinositol (GPI)-anchored glycoprotein (tentatively designated GPI-80) on human leukocytes that may be involved in the regulation of neutrophil adherence and migration. In this study, we examined by immuno- and scanning electron microscopy, the distribution of GPI-80 on neutrophil surfaces. GPI-80 was diffusely distributed on the surface of resting neutrophils and on the peripheral areas of adherent cells after stimulation with N-formyl-methionyl-leucyl-phenylalanine. After longer stimulation (60 min), GPI-80 decreased in number and was again diffusely distributed on the surfaces of round neutrophils. Few GPI-80 were detected on the ventral surfaces of adherent neutrophils. Clusters of GPI-80 were detected on the forward surfaces of neutrophils transmigrating through pores of nitrocellulose membranes. These results may give a morphological background of possible role of GPI-80 for neutrophil extravasation.
Adenoviral transduction of human E-selectin into isolated, perfused, rat aortic segments: anex vivomodel for studying leukocyte-endothelial interactions
Authors: Ishii Hideto , Yoshida Masayuki , Rosenzweig Anthony , Gimbrone Michael A , Yasukochi Yukio , Numano Fujio 
Published: September 2022

AbstractE-selectin, a member of the selectin family of adhesion molecules, is thought to play an important role in leukocyte-endothelial (EC) interactions during inflammation and atherosclerosis. To critically examine the role of E-selectin in leukocyte-EC interactions in the vascular system, we created a recombinant adenoviral vector containing a human E-selectin cDNA (AdRSVE-sel) and examined the effect of AdRSVE-sel in an ex vivo vascular model of a rat aortic segment. A segment of abdominal aorta was isolated from a male Sprague-Dawley rat transduced with AdRSVE-sel ex vivo. After 72 h, surface expression of transduced E-selectin in the segment was confirmed by Western blotting and immunohistochemistry using anti-E-selectin mAb. Aortic segments were connected to a perfusion system and the adhesion of human polymorphonuclear neutrophils (PMN), and a human monocytic cell line (THP-1) to the EC surface was studied in the presence of a physiological level of flow (0.85 ml/min, approximate luminal surface shear stress=1.76 dyn/cm2). Adhesion of PMN was assessed by scanning electron microscopy and quantified using fluorescently labeled PMN. AdRSVE-sel transduced aortic segments mediated significantly more PMN and THP-1 adhesion than control segments transduced with AdRSVLacZ. Pretreatment of AdRSVE-sel transduced aortic segments with anti-E-selectin mAb inhibited PMN adhesion significantly, as well as THP-1. These data indicate that human E-selectin expressed in rat aortic segments can support the adhesion of human PMN as well as THP-1 under physiological flow conditions. This genetically modified, excised, vascular-segment model provides a useful tool for the study of leukocyte recruitment in the vascular system.
α-Melanocyte-stimulating hormone peptides inhibit HIV-1 expression in chronically infected promonocytic U1 cells and in acutely infected monocytes
Authors: Barcellini Wilma , Colombo Gualtiero , La Maestra Letteria , Clerici Giuliana , Garofalo Letizia , Brini Anna T , Lipton James M , Catania Anna 
Published: September 2022

Abstract
The purpose of the present research was to determine if α-melanocyte-stimulating hormone (α-MSH) and its C-terminal tripeptide [α-MSH (11–13), KPV] alter HIV expression in infected cells. The results indicate that chronically HIV-1-infected promonocytic U1 cells produce α-MSH and that immunoneutralization of the endogenous peptide enhances HIV expression. Because U1 cells express the α-MSH receptor 1 (MC1R), an autocrine-inhibitory circuit based on the peptide and its receptor likely occurs in these cells. To determine effects of pharmacological concentrations of α-MSH peptides on HIV expression, we measured p24 antigen release by TNF-α-stimulated U1 cells exposed to a wide range of concentrations of synthetic α-MSH and KPV. Viral expression was reduced by both peptides. KPV also effectively reduced HIV replication in acutely infected monocyte-derived macrophages (MDM). The basis of the peptide influence on viral replication is at the transcriptional level; KPV inhibited activation of NF-κB that is known to enhance viral expression. Endogenous α-MSH likely contributes to natural defense against HIV. However, greater concentrations of synthetic peptide are much more effective in reducing HIV expression in infected cells.
Identification of mature and immature human thymic dendritic cells that differentially express HLA-DR and interleukin-3 receptor in vivo
Authors: Schmitt Christian , Fohrer Hélène , Beaudet Sylvie , Palmer Pierre , Alpha Marie-José , Canque Bruno , Gluckman Jean Claude , Dalloul Ali H 
Published: September 2022

Abstract
We have previously shown that thymic CD34+ cells have a very limited myeloid differentiation capacity and differentiatein vitro mostly into CD1a+-derived but not CD14+-derived dendritic cells (DC). Herein we characterized the human neonatal thymic DC extracted from the organ in relationship with the DC generated from CD34+ cells in situ. We show that in vivo thymic DC express E cadherin, CLA, CD4, CD38, CD40, CD44, and granulocyte-macrophage colony-stimulating factor-R (GM-CSF-R; CD116) but no CD1a. According to their morphology, functions, and surface staining they could be separated into two distinct subpopulations: mature HLA-DRhi, mostly interleukin-3-R (CD123)-negative cells, associated with thymocytes, some apoptotic, and expressed myeloid and activation markers but no lymphoid markers. In contrast, immature HLA-DR+ CD123hi CD36+ cells with monocytoid morphology lacked activation and myeloid antigens but expressed lymphoid antigens. The latter express pTα mRNA, which is also found in CD34+ thymocytes and in blood CD123hi DC further linking this subset to lymphoid DC. However, the DC generated from CD34+ thymic progenitors under standard conditions were pTα-negative. Thymic lymphoid DC showed similar phenotype and cytokine production profile as blood/tonsillar lymphoid DC but responded to GM-CSF, and at variance with them produced no or little type I interferon upon infection with viruses and did not induce a strict polarization of naive T cells into TH2 cells. Their function in the thymus remains therefore to be elucidated.
Heterogeneity of human peripheral blood monocyte subsets
Authors: Grage-Griebenow E , Flad H-D , Ernst M 
Published: September 2022

AbstractIn recent years the number of reports describing phenotypically and functionally distinct subsets of human blood leukocytes, and in particular of subtypes of antigen-presenting cells has continuously increased. A great diversity was described not only for dendritic cells (DC), but also for human blood monocytes (Mo) and macrophages (Mac). Similar to DC, the different types of Mo subsets could be defined by distinct phenotypes and immunoregulatory functions. The characterization of blood Mo subpopulations revealed that some of them exhibit common features with myeloid or lymphoid DC and tissue Mac, but also demonstrate the existence of novel unique cell populations. The generation of lymphoid and myeloid DC and their heterogeneity has been the subject of recent reviews. Here we focus on Mo from human peripheral blood and summarize the data (including our own) dealing with their phenotypic and functional, in particular immunoregulatory properties.
Requirement for STAT1 in LPS-induced gene expression in macrophages
Authors: Ohmori Yoshihiro , Hamilton Thomas A 
Published: September 2022

AbstractThis study examines the role of the signal transducer and activator of transcription 1 (STAT1) in induction of lipopolysaccharide (LPS)-stimulated gene expression both in vitro and in vivo. LPS-induced expression of an interferon (IFN)-inducible 10-kDa protein (IP-10), IFN regulatory factor-1 (IRF-1), and inducible nitric oxide synthase (iNOS) mRNAs was severely impaired in macrophages prepared fromStat1−/− mice, whereas levels of tumor necrosis factor α and KC (a C-X-C chemokine) mRNA in LPS-treated cell cultures were unaffected. A similar deficiency in LPS-induced gene expression was observed in livers and spleens from Stat1−/− mice. The reduced LPS-stimulated gene expression seen in Stat1−/− macrophages was not the result of reduced activation of nuclear factor κB. LPS stimulated the delayed activation of both IFN-stimulated response element and IFN-γ-activated sequence binding activity in macrophages from wild-type mice. Activation of these STAT1-containing transcription factors was mediated by the intermediate induction of type I IFNs, since the LPS-induced IP-10, IRF-1, and iNOS mRNA expression was markedly reduced in macrophages fromIFN-α/βR−/− mice and blocked by cotreatment with antibodies against type I IFN. These results indicate that indirect activation of STAT1 by LPS-induced type I IFN participates in promoting optimal expression of LPS-inducible genes, and they suggest that STAT1 may play a critical role in innate immunity against gram-negative bacterial infection.
Adenoviral gene delivery can inactivate Kupffer cells: role of oxidants in NF-κB activation and cytokine production
Authors: Wheeler Michael D , Yamashina Shunhei , Froh Matthias , Rusyn Ivan , Thurman Ronald G 
Published: September 2022

AbstractKupffer cells play a significant role in the pathogenesis of several liver diseases; therefore, a potential therapeutic strategy would be to inactivate the Kupffer cell with a gene-delivery system. Although recombinant adenovirus provides robust, transgene expression in parenchymal cells, whether adenovirus transduces Kupffer cells is unclear. Thus, the purpose of this study was to evaluate this possibility. In animals infected with adenovirus, Kupffer cells were identified positively to express adenoviral transgenes by immunohistochemical techniques and Western blot analysis, indicating that Kupffer cells are transduced in vivo. Indeed, isolated Kupffer cells were transduced in vitro with recombinant adenovirus in a dose-dependent manner. Moreover, adenoviral transduction of Kupffer cells was blocked by inhibitors of αVβ5 integrin, the co-receptor for adenovirus binding, supporting the hypothesis that adenovirus transduces Kupffer cells via an αVβ5 integrin-dependent mechanism. Indeed, it is shown here that Kupffer cells express αVβ5 integrins. In a functional assay, infection of isolated Kupffer cells with adenovirus containing superoxide dismutase or IκBα super-repressor blunted LPS-induced nuclear transcription factor kappa B (NF-κB) activation and tumor necrosis factor α (TNF-α) production but not IL-10 production. Moreover, superoxide production was blocked by expression of superoxide dismutase. These data support the hypothesis that LPS-induced NF-κB activation and TNF-α production in Kupffer cells are oxidant-dependent. These findings suggest that Kupffer cell-targeted approaches may be a potential therapeutic strategy against many inflammatory diseases including early alcohol-induced liver injury.
Polymorphonuclear granulocytes induce myocardial dysfunction during ischemia and in later reperfusion of hearts exposed to low-flow ischemia
Authors: Seligmann Christian , Bock Andreas , Leitsch Tobias , Schimmer Mike , Simsek Yusuf , Schultheiss Heinz-Peter 
Published: September 2022

AbstractPolymorphonuclear granulocytes (PMNs) are known to contribute to reperfusion injury of the heart. However, whether PMNs compromise myocardial function of hearts exposed to a low-flow ischemia has not been determined. Moreover, not much is known about deleterious effects of PMNs at different times during ischemia and reperfusion. Isolated, working guinea pig hearts were subjected to 30 min of low-flow ischemia and reperfusion. Homologous PMNs were applied as 1-min boluses in the presence of thrombin during either ischemia or the first or fifth minute of reperfusion, and postischemic recovery of external heart work (REHW) and intracoronary PMN retention (PMNR) were quantified. In further experiments, the radical scavenger superoxide dismutase (SOD) was added. Compared with controls without PMNs (REHW, 92.4%), application of PMNs led to a significant loss of myocardial function, which was detected at all three examination times. Moreover, intracoronary PMNR increased significantly in comparison with that of controls with hearts not exposed to ischemia or reperfusion. On the other hand, addition of SOD significantly increased REHW. Intracoronary PMNR was not significantly changed by coapplication of SOD. We conclude that thrombin-stimulated PMNs applied at different times during ischemia and reperfusion significantly impaired cardiac function in hearts exposed to a low-flow ischemia.
Nerve growth factor regulates TNF-α production in mouse macrophages via MAP kinase activation
Authors: Barouch Rina , Kazimirsky Gila , Appel Elena , Brodie Chaya 
Published: September 2022

AbstractIn this study, we examined the expression of nerve growth factor (NGF) and its receptors in mouse macrophages and the mechanisms involved in the effect of NGF on tumor necrosis factor (TNF)-α production. Macrophages expressed NGF and the NGF receptors TrkA and p75. Treatment of J744 cells or peritoneal macrophages with NGF induced a large increase in the production of TNF-α. In addition, NGF induced the secretion of nitric oxide in interferon-γ-treated J774 cells or lipopolysaccharide-treated peritoneal macrophages. The induction of TNF-α production by NGF was blocked by K252a, an inhibitor of the TrkA receptor. NGF induced phosphorylation and activation of extracellular signal-regulated kinase, Erk1/Erk2 and c-Jun amino-terminal kinase, whereas it did not induce phosphorylation of p38 mitogen-activated protein kinase. Inhibition of the MAP kinase-Erk kinase pathway with PD 098059 decreased the secretion of TNF-α by NGF. Our results suggest that NGF has an important role in the activation of macrophages during inflammatory responses via activation of mitogen-activated protein kinases.
Cloning and expression analysis of a novel G-protein-coupled receptor selectively expressed on granulocytes
Authors: Yousefi Shida , Cooper Paul R , Potter Suzanne L , Mueck Beatrice , Jarai Gabor 
Published: September 2022

AbstractThe migration of neutrophils into sites of acute and chronicinflammation is mediated by chemokines. We used degenerate-primerreverse transcriptase-polymerase chain reaction (RT-PCR) to analyzechemokine receptor expression in neutrophils and identify novelreceptors. RNA was isolated from human peripheral blood neutrophils andfrom neutrophils that had been stimulated for 5 h withgranulocyte-macrophage colony-stimulating factor or by coculturing withprimary human bronchial epithelial cells. Amplification products werecloned, and clone redundancy was determined. Seven knownG-protein-coupled receptors were identified among 38 clones—CCR1,CCR4, CXCR1, CXCR2, CXCR4, HM63, and FPR1—as well as a novel gene,EX33. The full-length EX33 clone was obtained, and an insilico approach was used to identify the putative murine homologue. TheEX33 gene encodes a 396-amino-acid protein with limitedsequence identity to known receptors. Expression studies of severalknown chemokine receptors and EX33 revealed that resting neutrophilsexpressed higher levels of CXCRs and EX33 compared with activatedneutrophils. Northern blot experiments revealed that EX33 is expressedmainly in bone marrow, lung, and peripheral blood leukocytes. UsingRT-PCR analysis, we showed more abundant expression of EX33 inneutrophils and eosinophils, in comparison with that in T- or B-lymphocytes, indicating cell-specific expression amongleukocytes.
Phosphatidylcholine-specific phospholipase C regulates activation of RAW264.7 macrophage-like cells by lipopeptide JBT3002
Authors: Zhang Fahao , Zhao Guiling , Dong Zhongyun 
Published: September 2022

AbstractPhospholipase activities are thought to be involved in the activation of macrophages by lipopolysaccharide (LPS). Because our previous studies showed that the synthetic lipopeptide JBT3002 might activate macrophages via signaling pathways similar to those used by LPS, we investigated whether phospholipase activities are required for activation of macrophages by JBT3002. Treatment of RAW264.7 murine macrophage-like cells with JBT3002 stimulated expression of both inducible nitric oxide synthase (iNOS) and tumor necrosis factor-α (TNF-α) in a dose-dependent manner. The JBT3002-induced production of nitric oxide and TNF-α was significantly inhibited by tricyclodecan-9-yl xanthogenate (D609), a selective inhibitor of phosphatidylcholine (PC)-specific phospholipase C (PC-PLC). JBT3002-induced expression of steady-state mRNA for both iNOS and TNF-α was inhibited by D609. Cells treated with JBT3002 had greater production of diacylglycerol (DAG) in 2 min, which lasted for at least 30 min and could be blocked by D609. Activation of RAW264.7 cells was not affected by butanol, a PC-specific phospholipase D inhibitor, and treatment with JBT3002 did not affect phosphatidic acid formation. RAW264.7 cells treated with DAG analogue 1-oleoyl-2-acetyl-sn-glycerol, in the presence of interferon-γ, produced TNF-α. These results suggested that activation of RAW264.7 cells by JBT3002 requires PC-PLC activity.