bluuebunny/crossref_metadata_2025_split huggingface dataset:
Human Herpesvirus Type 8 Interleukin-6 Homologue Is Functionally Active on Human Myeloma Cells
Authors: Burger Renate , Neipel Frank , Fleckenstein Bernhard , Savino Rocco , Ciliberto Gennaro , Kalden Joachim R. , Gramatzki Martin 
Published: October 2019

AbstractSeroepidemiology and polymerase chain reaction studies have strongly suggested that human herpesvirus type 8 (HHV-8) is associated with Kaposi's sarcoma, Castleman's disease, and body cavity-based lymphoma. The genome of HHV-8 harbors a viral analogue of the interleukin-6 (IL-6) gene. The amino acid sequence of the viral IL-6 (vIL-6) protein is 24.7% identical to human IL-6 (hIL-6). IL-6 as a B-cell growth and differentiation factor is known to play an essential role in the pathophysiology of B-cell tumors. Thus, it seems possible that virus-encoded IL-6 contributes to malignant growth of HHV-8–positive B-cell lymphatic tumors. We have tested a preparation of HHV-8–derived IL-6 for the ability to promote the proliferation of the human myeloma cell line INA-6, which is strictly dependent on exogenous IL-6 for growth and survival. Viral IL-6 significantly induced DNA synthesis of INA-6 cells, but required much more protein on a weight basis when compared with hIL-6 for maximal proliferation. The proliferative effect of vIL-6 was almost completely inhibited by a combination of anti–IL-6 receptor (IL-6R) and anti-gp130 antibodies or IL-6R superantagonist Sant7 and anti-gp130 antibodies. This report demonstrates that vIL-6 has proliferative activity on human cells and that the IL-6R and gp130 are involved in vIL-6 signaling in the myeloma cell line INA-6.
Molecular Modeling of Ligand and Mutation Sites of the Type A Domains of Human von Willebrand Factor and Their Relevance to von Willebrand's Disease
Authors: Jenkins P. Vincent , Pasi K. John , Perkins Stephen J. 
Published: October 2019

Abstractvon Willebrand factor (vWF) is a large multimeric, multidomain glycoprotein found in platelets, endothelial cells and plasma. The A1, A2, and A3 domains in vWF mediate binding to glycoprotein Ib, ristocetin, botrocetin, collagen, sulphatides, and heparin and provide a protease cleavage site. Mutations causing types 2B, 2M, and 2A von Willebrand's disease (vWD) are located in the A1 and A2 domains. Homology modeling was performed to provide a molecular interpretation of vWF function and mutation sites. This was based on our previous alignment of 75 vWF-A sequences, the doubly wound α/β fold seen in recent vWF-A crystal structures from complement receptor type 3 and lymphocyte function-associated antigen-1, and our new alignment of 28 vWF A1 and A2 sequences from different species. The active site in doubly-wound α/β folds forms a crevice that is located at the switch point between the two halves of the central β-sheet, and usually contains two metal-binding Asp residues in the vWF-A superfamily. Although one of these Asp residues is absent from the A1, A2, and A3 domains, this crevice is shown to correspond to the ristocetin binding site in the A1 domain and the protease cleavage site in the A2 domain. The residues R571-K572-R578-R579-K585 are found to be conserved in 28 A1 sequences and are predicted to constitute the heparin binding site in the A1 domain. Inspection of the type 2M vWD mutation sites that are involved in downregulation of glycoprotein Ib (GpIb) binding to vWF shows that these are spatially clustered at the carboxyl-edge of the β-sheet and above it in the A1 domain and may directly perturb GpIb binding. In contrast, the type 2B vWD mutation sites that are involved in upregulation of GpIb binding to vWF are spatially clustered at the amino edge of this β-sheet and below it and are located on the opposite side of the A1 domain from the type 2M mutation sites. The type 2B mutations are located between the heparin and GpIb binding sites. Because heparin binding inhibits the interaction with GpIb, this provides an explanation of vWF upregulation. The type 2A vWD mutation sites in the A2 domain correspond to buried residues that are otherwise 100% conserved across all 28 species, and are likely to be important for the correct folding of the A2 domain and its physiologically important protease site.
A Syndrome of Peripheral Blood T-Cell Infection With Epstein-Barr Virus (EBV) Followed by EBV–Positive T-Cell Lymphoma
Authors: Kanegane Hirokazu , Bhatia Kishor , Gutierrez Marina , Kaneda Hisashi , Wada Taizo , Yachie Akihiro , Seki Hidetoshi , Arai Takashi , Kagimoto Sei-ichi , Okazaki Minoru , Oh-ishi Tsutomu , Moghaddam Amir , Wang Fred , Tosato Giovanna 
Published: October 2019

AbstractThe role of Epstein-Barr virus (EBV) in the pathogenesis of severe, chronic active EBV infection and its complications is unclear. We investigated two Japanese patients diagnosed with severe, chronic active EBV infection who subsequently developed EBV–positive T-cell lymphoma. The patients displayed abnormally high antibody titers to EBV antigens, and had evidence of peripheral blood CD4+T-cell infection with EBV, 19 months and 3 months, respectively, before the diagnosis of EBV–positive T-cell lymphoma. The lymphomas were infected with monoclonal EBV and expressed the EBV latency genes EBNA-1, LMP-1, and LMP-2. Genetic studies showed that the virus detected in the T-cell lymphoma was indistinguishable, with respect to type and previously defined LMP-1 and EBNA-1 gene variations, from virus detected in the peripheral blood T cells 19 months earlier. These studies support an important pathogenetic role of T-cell infection with EBV in chronic active EBV infection and in the EBV–positive T-cell lymphoma that followed.
Impaired Ca2+-Induced Tyrosine Phosphorylation and Defective Lipid Scrambling in Erythrocytes From a Patient With Scott Syndrome: A Study Using an Inhibitor for Scramblase That Mimics the Defect in Scott Syndrome
Authors: Dekkers David W.C. , Comfurius Paul , Vuist Wim M.J. , Billheimer Jeffrey T. , Dicker Ira , Weiss Harvey J. , Zwaal Robert F. A. , Bevers Edouard M. 
Published: October 2019

AbstractScott syndrome is an hereditary bleeding disorder characterized by a deficiency in platelet procoagulant activity. Unlike normal blood cells, Scott platelets, as well as erythrocytes and lymphocytes, are strongly impaired in their ability to scramble their membrane phospholipids when challenged with Ca2+. In normal cells this collapse of membrane asymmetry leads to surface exposure of phosphatidylserine. Here we report that Scott erythrocytes show an apparent defect in tyrosine phosphorylation on treatment with Ca2+-ionophore. Diminished tyrosine phosphorylation was also apparent in activated Scott platelets, but much less pronounced than observed in red blood cells. On the other hand, tyrosine phosphorylation profiles observed in Scott red blood cell ghosts after sealing in the presence of adenosine triphosphate (ATP) were indistinguishable from those obtained from normal ghosts. Several observations argue in favor of a mechanism in which tyrosine phosphorylation in red blood cells is facilitated by, rather than required for scrambling of membrane lipids. Staurosporin blocks tyrosine phosphorylation in normal red blood cells, but does not inhibit the lipid scrambling process. White ghosts from normal erythrocytes, resealed in the absence of ATP, exhibit Ca2+-induced lipid scrambling without tyrosine phosphorylation. A selective inhibitor of Ca2+-induced lipid scrambling also showed an apparent inhibition of tyrosine phosphorylation in ionophore-treated normal red blood cells, similar to that observed in Scott erythrocytes. While this inhibitor also suppressed Ca2+-induced lipid scrambling in ghosts that were sealed in the presence of ATP, it did not inhibit tyrosine kinase activity. We conclude that the apparent deficiency in tyrosine phosphorylation in Scott cells is an epiphenomenon, possibly associated with a defect in phospholipid scrambling, but not causal to this defect.
Eotaxin Induces a Rapid Release of Eosinophils and Their Progenitors From the Bone Marrow
Authors: Palframan Roger T. , Collins Paul D. , Williams Timothy J. , Rankin Sara M. 
Published: October 2019

AbstractThe CC-chemokine eotaxin is a potent eosinophil chemoattractant that stimulates recruitment of eosinophils from the blood to sites of allergic inflammation. Mobilization from the bone marrow is an important early step in eosinophil trafficking during the allergic inflammatory response. In this paper we examine the potential of eotaxin to mobilize eosinophils and their progenitors from bone marrow. Eotaxin stimulated selective, dose-dependent chemotaxis of guinea pig bone marrow eosinophils in vitro. Intravenous injection of eotaxin (1 nmol/kg) into guinea pigs in vivo stimulated a rapid blood eosinophilia (from 3.9 ± 1.2 to 28 ± 9.9 × 104eosinophils/mL at 30 minutes) and a corresponding decrease in the number of eosinophils retained in the femoral marrow (from 9.0 ± 0.8 to 4.8 ± 0.8 × 106 eosinophils per femur). To show a direct release of eosinophils from the bone marrow an in situ perfusion system of the guinea pig femoral bone marrow was developed. Infusion of eotaxin into the arterial supply of the perfused femoral marrow stimulated a rapid and selective release of eosinophils into the draining vein. In addition, eotaxin stimulated the release of colony-forming progenitor cells. The cytokine interleukin-5 was chemokinetic for bone marrow eosinophils and exhibited a marked synergism with eotaxin with respect to mobilization of mature eosinophils from the femoral marrow. Thus, eotaxin may be involved in both the mobilization of eosinophils and their progenitors from the bone marrow into the blood and in their subsequent recruitment into sites of allergic inflammation.
Rat Neutrophils Express α4 and β1 Integrins and Bind to Vascular Cell Adhesion Molecule-1 (VCAM-1) and Mucosal Addressin Cell Adhesion Molecule-1 (MAdCAM-1)
Authors: Davenpeck Kelly L. , Sterbinsky Sherry A. , Bochner Bruce S. 
Published: October 2019

AbstractThe α4 integrins, which are constitutively expressed on all human leukocyte subtypes except neutrophils, interact with vascular cell adhesion molecule-1 (VCAM-1) and mucosal addressin cell adhesion molecule (MAdCAM-1) on endothelium to mediate selective recruitment of leukocyte subpopulations, other than neutrophils, to sites of inflammation. However, here we report that a different paradigm of leukocyte recruitment may exist in the rat. Flow cytometric analysis of rat neutrophils using a panel of monoclonal antibodies which recognize rat α4 and β1 integrins showed consistent, low levels of expression. Although α4 was expressed at lower levels on neutrophils than all other rat leukocytes, this level of expression was sufficient to mediate significant levels of α4- and β1-dependent neutrophil adhesion to rat and human VCAM-1, and α4-dependent, but β1-independent, adhesion to human MAdCAM-1. These data suggest that rat neutrophils, unlike other species, may use α4 integrins to traffic to sites of inflammation in vivo.
Somatic Hypermutation, Clonal Diversity, and Preferential Expression of the VH 51p1/VL kv325 Immunoglobulin Gene Combination in Hepatitis C Virus–Associated Immunocytomas
Authors: Ivanovski Martin , Silvestri Federico , Pozzato Gabriele , Anand Shubha , Mazzaro Cesare , Burrone Oscar R. , Efremov Dimitar G. 
Published: October 2019

AbstractA high prevalence of chronic hepatitis C virus (HCV) infection has recently been shown in a subset of B-cell non-Hodgkin's lymphomas, most of which belong to the lymphoplasmacytoid lymphoma/immunocytoma subtype and are characterized by the production of a monoclonal IgM cryoglobulin with rheumatoid factor activity. To better define the stage of differentiation of the malignant B cell and to investigate the role of chronic antigen stimulation in the pathogenesis of the HCV-associated immunocytomas, we analyzed the variable (V) region gene repertoire in 16 cases with this type of tumor. The lymphoma-derived V gene sequences were successfully determined in 8 cases; 5 of them expressed the 51p1 VH gene in combination with the kv325 VL gene. Moreover, a monoclonal 51p1-expressing B-cell population was detected in 4 of the remaining immunocytomas by an allele-specific Ig gene fingerprinting assay, indicating that HCV-associated immunocytomas represent clonal proliferations of a highly selected B-cell population. Somatic mutations and intraclonal diversity were observed in all of the lymphoma V genes, and clonally related IgM and IgG VH transcripts indicative of isotype switching were present in one case. These findings are consistent with an antigen-driven process and support a role for chronic antigen stimulation in the growth and clonal evolution of HCV-associated immunocytomas.
Mechanisms of Growth Control of Kaposi's Sarcoma–Associated Herpes Virus–Associated Primary Effusion Lymphoma Cells
Authors: Asou Hiroya , Said Jonathan W. , Yang Rong , Munker Reinhold , Park Dorothy J. , Kamada Nanao , Koeffler H. Phillip 
Published: October 2019

AbstractPrimary effusion lymphoma (PEL) is a distinct clinicopathologic entity associated with Kaposi's sarcoma-associated herpes virus (KSHV). Several cytokines, including interleukin-6 (IL-6), basic fibroblast growth factor (bFGF), and platelet-derived growth factor (PDGF) may be important for survival of KS cells. However, little is known about the interaction of cytokines with KSHV-infected lymphocytes from PEL. Therefore, we investigated what cytokines were produced by KSHV-infected PEL cell lines (KS-1, BC-1, BC-2), what cytokine receptors were expressed by these cells, what response these cells had to selected cytokines, and what was the effect of IL-6 antisense phosphorothioated oligonucleotides. Reverse transcriptase-polymerase chain reaction (RT-PCR) and protein studies showed that these three cell lines produced IL-10, IL-6, and the receptors for IL-6. The granulocyte macrophage colony-stimulating factor (GM-CSF), IL-1β, IL-8, IL-12, bFGF, PDGF, and c-kit transcripts were not detected in the cell lines. High levels (0.7 to 5 ng/mL/106cells/48 hours) of IL-6 protein were consistently detected in supernatants of the cell lines by enzyme-linked immunosorbent assay (ELISA) tests. In clonogenic assays, interferon-α (IFN-α) and IFN-γ suppressed the clonal growth of the PEL cells, but GM-CSF, IL-4, IL-6, IL-8, IL-10, and oncostatin M did not change it. We examined for several autocrine loops that have been suggested to occur in KS. Experiments using antisense oligonucleotides showed that the clonal growth of KS-1 and BC-1 was nearly 100% inhibited by IL-6 antisense oligonucleotides (10 μmol/L), but not at all by either oligonucleotides (≤10 μmol/L) to IL-6 sense, IL-6 scrambled, viral IL-6 (vIL-6) antisense, or IL-10 antisense. Furthermore, the IL-6 antisense oligonucleotides had no effect on two B-cell lymphoma cell lines, which were not infected with KSHV. Addition of IL-6 antibody did not inhibit clonal growth of any of the cell lines. Taken together, we have defined the cytokines and their receptors expressed on PEL cells and have found that these cells synthesized IL-6 and IL-6 receptors; interruption of this pathway by IL-6 antisense oligonucleotides specifically prevented the growth of these cells. These findings will offer potential new therapeutic strategies for PEL.
Isolation and Characterization of the cDNA for Mouse Neutrophil Collagenase: Demonstration of Shared Negative Regulatory Pathways for Neutrophil Secondary Granule Protein Gene Expression
Authors: Lawson Nathan D. , Khanna-Gupta Arati , Berliner Nancy 
Published: October 2019

AbstractA characteristic of normal neutrophil maturation is the induction of secondary granule protein (SGP) mRNA expression. Several leukemic human cell lines mimic normal morphologic neutrophil differentiation but fail to express SGPs, such as lactoferrin (LF) and neutrophil gelatinase (NG). In contrast, two murine cell lines (32D C13 and MPRO) are able to differentiate into neutrophils and induce expression of LF and NG. Therefore, to study the normal regulation and function of these genes, the corresponding murine homologs must be isolated. Using cDNA representational difference analysis (RDA) to compare a committed myeloid progenitor cell line (EPRO) with the multipotent stem cell line from which it was derived (EML), we isolated a fragment bearing homology to human neutrophil collagenase (hNC). Here, we describe the cloning and characterization of a full-length (∼2 kb) clone that exhibits nearly 65% nucleotide and 73% amino acid identity to hNC. Ribonuclease protection analysis (RPA) of the tissues and cell lines shows that mouse NC (mNC) is expressed only in cell lines exhibiting neutrophilic characteristics, further confirming its identity as the mouse homolog of hNC. Furthermore, we have demonstrated a shared negative regulatory pathway for this and other SGP genes. We have previously shown that CCAAT displacement protein (CDP/cut) binds to a specific region of the LF promoter, and overexpression of CDP blocks G-CSF–induced upregulation of LF gene expression in 32D C13 cells. We show here that in these cells, upregulation of both NC and NG is also blocked. CDP is thus the first identified transcription factor that is a candidate for mediating the shared regulation of neutrophil SGP protein genes.
gp130, The Cytokine Common Signal-Transducer of Interleukin-6 Cytokine Family, Is Downregulated in T Cells In Vivo by Interleukin-6
Authors: Wang Xue-Jie , Taga Tetsuya , Yoshida Kanji , Saito Mikiyoshi , Kishimoto Tadamitsu , Kikutani Hitoshi 
Published: October 2019

Abstractgp130 is a common signal-transducing receptor component for the interleukin-6 (IL-6) family of cytokines. To investigate the expression of gp130 in T-cell subsets and its regulation, anti-murine gp130 monoclonal antibody (MoAb) was used for flow cytometric analysis. In normal mice, gp130 was differentially expressed in thymocyte and splenic T-cell subpopulations defined by CD4/CD8 expression. In aged MRL/lpr mice, although gp130 expression was detectable in splenic CD4+ or CD8+ T cells, gp130 expression was significantly downregulated. Because serum levels of IL-6 and soluble IL-6 receptor (sIL-6R) are elevated in these mice, we examined the possibility that the downregulation of gp130 expression on splenic T cells might be produced in response to continuous activation of gp130 by high levels of serum IL-6. In transgenic mice overexpressing IL-6, gp130 expression in the splenic T cells was significantly decreased. After stimulation with IL-6 in vitro, the level of gp130 on CD4+ or CD8+ splenic T cells from normal mice was significantly decreased. These results suggest that the expression of gp130 in splenic T cells could be downregulated by the IL-6 stimulation under physiological or pathological circumstances.
Highly Sensitive Fluorescence In Situ Hybridization Method to Detect Double BCR/ABL Fusion and Monitor Response to Therapy in Chronic Myeloid Leukemia
Authors: Dewald Gordon W. , Wyatt William A. , Juneau Amy L. , Carlson Richard O. , Zinsmeister Alan R. , Jalal Syed M. , Spurbeck Jack L. , Silver Richard T. 
Published: October 2019

Abstract
We investigated a new method using fluorescence in situ hybridization and DNA probes that span the common breakpoints of t(9;22)(q34;q11.2) and that detect double BCR/ABL fusion (D-FISH) in bone marrow cells with this translocation, one on the abnormal chromosome 9 and one on the Philadelphia chromosome (Ph chromosome). D-FISH patterns were abnormal in 30 of 30 specimens with classic, simple, complex, and masked Ph chromosomes. Based on 200 nuclei from each of 30 normal specimens, the mean percentage of false-positive cells was 0.25 ± 0.39. Thirty-seven specimens from 10 patients were studied before treatment and two or more times at 4-month intervals after treatment with interferon-α2b (IFN-α2b) with or without ara-C. Based on 200 nuclei, the results of D-FISH in these specimens correlated closely with quantitative cytogenetics and accurately quantified disease within a few percent. We studied 6,000 nuclei for each of six specimens, three normal and three from patients with chronic myeloid leukemia (CML) in cytogenetic remission. The normal cutoff for 6,000 nuclei was 0.079% and patients in cytogenetic remission had residual disease ranging from 7 (0.117%) to 53 (0.883%) Ph-positive nuclei. We conclude that D-FISH can detect the Ph chromosome and its variant translocations and accurately quantify disease in CML at diagnosis and at all times after treatment, including cytogenetic remission.
Inhibition of BCR-ABL Expression With Antisense Oligodeoxynucleotides Restores β1 Integrin-Mediated Adhesion and Proliferation Inhibition in Chronic Myelogenous Leukemia Hematopoietic Progenitors
Authors: Bhatia Ravi , Verfaillie Catherine M. 
Published: October 2019

AbstractChronic myelogenous leukemia (CML) is characterized by the continuous proliferation and abnormal circulation of malignant hematopoietic progenitors. This may be related to the unresponsiveness of CML progenitors to β1 integrin adhesion receptor-mediated inhibition of progenitor proliferation by the marrow microenvironment. In hematopoietic cell lines, the BCR-ABL oncogene product, p210BCR-ABL, interacts with a variety of cytoskeletal elements important for normal integrin signaling. We studied the role of p210BCR-ABL in abnormal integrin function in CML by evaluating the effect of inhibition of BCR-ABL expression with antisense oligodeoxynucleotides (AS-ODNs) on integrin-mediated adhesion and proliferation inhibition of malignant primary progenitors from CML marrow. Preincubation of CML CD34+HLA-DR+(DR+) cells with breakpoint-specific AS-ODNs significantly increased adhesion of CML progenitors to stroma and fibronectin (FN). Pretreatment with breakpoint-specific ODNs also resulted in significant inhibition of CML progenitor proliferation after ligand or antibody-mediated β1 integrin engagement. Breakpoint-specific ODNs were significantly more effective in restoring CML progenitor adhesion and proliferation inhibition than control ODNs. BCR-ABL mRNA and p210BCR-ABL levels in CML CD34+ cells were significantly reduced after incubation with breakpoint-specific AS-ODN. These studies indicate a role for BCR-ABL in abnormal circulation and defective integrin-dependent microenvironmental regulation of proliferation of CML hematopoietic progenitors.
Mouse Hypoxia-Inducible Factor-1α Is Encoded by Two Different mRNA Isoforms: Expression From a Tissue-Specific and a Housekeeping-Type Promoter
Authors: Wenger Roland H. , Rolfs Andreas , Spielmann Patrick , Zimmermann Dieter R. , Gassmann Max 
Published: October 2019

Abstract
Hypoxic induction of erythropoietin (Epo) and other oxygen-dependent genes is mediated by the hypoxia-inducible factor-1 (HIF-1), a heterodimeric transactivator consisting of an α and a β subunit. We previously found that the mouse gene encoding HIF-1α harbors two alternative first exons (I.1 and I.2), giving rise to two different HIF-1α mRNA isoforms. Here, we show by RNase protection analysis that the exon I.1-derived mRNA isoform is differentially expressed in mouse tissues, being highest in kidney, tongue, stomach, and testis, but undetectable in liver, whereas the exon I.2 mRNA isoform is ubiquitously expressed. Sequence and methylation analysis showed that, in contrast to exon I.1, exon I.2 resides within a region showing typical features of a CpG island, known to be associated with the 5′ end of housekeeping genes. We identified a 232-bp minimal exon I.2 promoter that strongly induced reporter gene expression in mouse L929 fibroblasts and Hepa1 hepatoma cells. In contrast to L929 cells, the exon I.1 promoter was inactive in Hepa1 cells and hypoxic exposure (1% O2) markedly reduced exon I.2 promoter activity in Hepa1 cells. Prolonged exposure of mice to hypoxia (7.5% O2 for up to 72 hours) also caused a decrease in liver HIF-1α mRNA, whereas aldolase mRNA levels increased. These findings might be related to the relatively low Epo levels in the adult liver.