bluuebunny/crossref_metadata_2025_split huggingface dataset:
Erythroblastic Synartesis: An Auto-immune Dyserythropoiesis
Authors: Cramer Elisabeth M. , Garcia Isabel , Massé Jean-Marc , Zini Jean-Marc , Lambin Patrick , Oksenhendler Eric , Souni Fadila , Smith Mark , Flandrin Georges , Breton-Gorius Janine , Tobelem Gérard , Casadevall Nicole 
Published: October 2019

AbstractErythroblastic synartesis is a rare form of acquired dyserythropoiesis, first described by Breton-Gorius et al in 1973. This syndrome is characterized by the presence of septate-like membrane junctions and “glove finger” invaginations between erythroblasts, which are very tightly linked together. This phenomenon, responsible for ineffective erythropoiesis, leads to an isolated severe anemia with reticulocytopenia. In the following report, we describe 3 new cases of erythroblastic synartesis associated with dysimmunity and monoclonal gammapathy. In all cases, the diagnosis was suggested by characteristic morphological appearance of bone marrow smears, and further confirmed by electron microscopy. Ultrastructural examination of abnormal erythroblast clusters showed that these cells were closely approximated with characteristic intercellular membrane junctions. The pathogenesis of the dyserythropoiesis was modeled in vitro using crossed erythroblast cultures and immunoelectron microscopy: when cultured in the presence of autologous serum, the erythroblasts from the patients displayed synartesis, whereas these disappeared when cultured in normal serum. Moreover, synartesis of normal erythroblasts were induced by the patient IgG fraction. Immunogold labeling showed that the monoclonal IgG were detected in, and restricted to, the synartesis. A discrete monoclonal plasmacytosis was also found in the patient bone marrow. The adhesion receptor CD36 appeared to be concentrated in the junctions, suggesting that it might be involved in the synartesis. These experiments indicated that a monoclonal serum immunoglobulin (IgG in the present cases) directed at erythroblast membrane antigen was responsible for the erythroblast abnormalities. Specific therapy of the underlying lymphoproliferation was followed by complete remission of the anemia in these cases.
A Randomized, Double-Blind, Placebo-Controlled Study With Pegylated Recombinant Human Megakaryocyte Growth and Development Factor (PEG-rHuMGDF) as an Adjunct to Chemotherapy for Adults With De Novo Acute Myeloid Leukemia
Authors: Archimbaud Eric , Ottmann Oliver G. , Yin John A. Liu , Lechner Klaus , Dombret Herve , Sanz Miguel A. , Heil Gerhard , Fenaux Pierre , Brugger Wolfram , Barge Alan , O’Brien-Ewen Caroline , Matcham James , Hoelzer Dieter 
Published: October 2019

Abstract
To determine the safety, biologic, and clinical benefits of pegylated recombinant human megakaryocyte growth and development factor (PEG-rHuMGDF; Amgen, Thousand Oaks, CA) after myelosuppressive chemotherapy in acute myeloid leukemia (AML), 108 adult patients with de novo AML were randomized to receive either PEG-rHuMGDF (2.5 μg/kg/d or 5 μg/kg/d) for up to 21 doses (group A), a single dose of 2.5 μg/kg PEG-rHuMGDF, 7 daily doses of 2.5 μg/kg PEG-rHuMGDF (group B), or placebo. The greatest biologic activity was seen in group A with a median peak platelet count of 1,084 × 109/L, occurring at a median 9 days after the last dose of study drug, compared with 517 × 109/L and 390 × 109/L in group B and placebo group, respectively. Thrombocytosis (platelets &gt;1,000 × 109/L) was seen at rates of 52%, 8%, and 9% in groups A, B, and placebo, respectively, but were not associated with any adverse event. There was no effect on median time to transfusion independent platelet recovery (≥20 × 109/L). The median time to neutrophil recovery (≥500/μL) and red blood cell transfusion requirements were similar in all groups, and there was no apparent stimulation of leukemia. PEG-rHuMGDF was biologically active and well tolerated. Further investigation of dose and scheduling is required, specifically earlier dosing before and during chemotherapy.
Cellular Vascular Endothelial Growth Factor Is a Predictor of Outcome in Patients With Acute Myeloid Leukemia
Authors: Aguayo Alvaro , Estey Elihu , Kantarjian Hagop , Mansouri Taghi , Gidel Cristi , Keating Michael , Giles Francis , Estrov Zeev , Barlogie Bart , Albitar Maher 
Published: October 2019

AbstractVascular endothelial growth factor (VEGF) is a potent mitogen for vascular endothelial cells. It has been associated with angiogenesis, growth, dissemination, metastasis, and poor outcome in solid tumors. To assess cellular VEGF levels and their prognostic significance in newly diagnosed acute myeloid leukemia (AML), we used a radioimmunoassay (RIA) to quantify VEGF levels in stored samples obtained before treatment from 99 patients with newly diagnosed AML treated at the MD Anderson Cancer Center from 1996 to 1998. Outcome in the 99 patients was representative of that observed in all patients seen at this institution with this diagnosis during these years, but the 99 patients had higher white blood cell (WBC) and blast counts than the other patients. Results of the RIA were confirmed by Western blot. There was a relationship between increasing VEGF levels and shorter survival (P = .01), as well as shorter disease-free survival, both from start of treatment and from complete response (CR) date. In contrast, there was no relationship between VEGF level and WBC or blast count, or between VEGF level and such established prognostic factors as age, cytogenetics, performance status, or presence of an antecedent hematologic disorder, and multivariate analysis indicated that VEGF was still prognostic for the above outcomes after accounting for these factors, as well as treatment. Our results suggest that at least in AML patients with higher WBC and blast counts, cellular VEGF level is an independent predictor of outcome.
Changes in Chromatin Organization at the Neutrophil Elastase Locus Associated With Myeloid Cell Differentiation
Authors: Wong Edmond T.L. , Jenne Dieter E. , Zimmer Michael , Porter Susan D. , Gilks C. Blake 
Published: October 2019

AbstractNeutrophil elastase, proteinase-3, and azurocidin are primary components of neutrophil azurophilic granules and are encoded by closely linked genes (gene symbols ELA2, PRTN3, and AZU1, respectively) in a region of approximately 50 kb. These genes are coordinately expressed in a granulocyte-specific fashion, but the mechanisms defining this pattern of expression are unknown. To understand the role of chromatin organization in governing the expression of ELA2, PRTN3, and AZU1, we mapped this region of chromosome 19 and identified the adipsin (complement factor D) gene in proximity to the 3′ end of ELA2. We then examined the changes in chromatin structure at the locus which accompany myeloid cell differentiation and identified 17 DNase I hypersensitive sites (DHS 1 to 17) in U-937 cells, an early myelomonocytic cell line expressing high levels of neutrophil elastase. Chemically induced differentiation and concomitant downregulation of AZU1, PRTN3, and ELA2 transcription in U-937 cells is not accompanied by changes in the DHS-pattern. Mature neutrophils, however, do not carry any of these hypersensitive sites, indicating a large degree of chromatin remodeling at this locus accompanying terminal granulocytic differentiation. Sixteen of the 17 DHS identified in U-937 cells are also present in the HL-60 myelomonocytic cell line. Hematopoietic cell lines representing the early erythroid and lymphocyte lineages, and a nonhematopoietic cell line display a subset of the hypersensitive sites. The altered chromatin structure specific to cells that actively transcribe the AZU1-PRTN3-ELA2 genes suggests that chromatin reorganization is an important mechanism regulating the myeloid-specific transcription of this gene cluster.
SCL Expression in the Mouse Embryo Detected With a Targeted lacZ Reporter Gene Demonstrates Its Localization to Hematopoietic, Vascular, and Neural Tissues
Authors: Elefanty Andrew G. , Begley C. Glenn , Hartley Lynne , Papaevangeliou Bette , Robb Lorraine 
Published: October 2019

AbstractThe helix-loop-helix transcription factor SCL (TAL1) is indispensable for blood cell formation in the mouse embryo. We have explored the localization and developmental potential of cells fated to express SCL during murine development using SCL-lacZmutant mice in which the Escherichia coli lacZreporter gene was ‘knocked in’ to the SCL locus. In addition to the hematopoietic defect associated with SCL deficiency, the yolk sac blood vessels in SCLlacZ/lacZ embryos formed an abnormal primary vascular plexus, which failed to undergo subsequent remodeling and formation of large branching vessels. Intraembryonic vasculogenesis in precirculationSCLlacZ/lacZ embryos appeared normal but, in embryos older than embryonic day (E) 8.5 to E9, absolute anemia leading to severe hypoxia precluded an accurate assessment of further vascular development. In heterozygous SCLlacZ/w embryos, lacZ was expressed in the central nervous system, vascular endothelia, and primitive and definitive hematopoietic cells in the blood, aortic wall, and fetal liver. Culture of fetal liver cells sorted for high and low levels of β galactosidase activity fromSCLlacZ/w heterozygous embryos indicated that there was a correlation between the level of SCL expression and the frequency of hematopoietic progenitor cells.
Immunophenotypic Analysis of Peripheral Blood and Bone Marrow in the Staging of B-Cell Malignant Lymphoma
Authors: Hanson Curtis A. , Kurtin Paul J. , Katzmann Jerry A. , Hoyer James D. , Li Chin-Yang , Hodnefield Janice M. , Meyers Cecelia H. , Habermann Thomas M. , Witzig Thomas E. 
Published: October 2019

Abstract
This study evaluated the contributing roles of flow cytometric immunophenotyping of blood and bone marrow and immunohistochemical paraffin section staining of bone marrow biopsies in the staging of B-cell malignant lymphoma. Flow immunophenotyping was performed on a marrow specimen in 175 cases; a corresponding blood specimen was also immunophenotyped in 135 of these cases. Morphologic marrow involvement by lymphoma was found in 59 cases; flow immunophenotyping identified 54 cases with a monoclonal B-cell process: morphology-positive/flow-positive (n = 49), morphology-positive/flow-negative (n = 10), morphology-negative/flow-positive (n = 5), and morphology-negative/flow-negative (n = 111). The 10 morphology-positive/flow-negative cases included 5 follicular and 5 large-cell lymphomas with minimal marrow involvement. All 5 morphology-negative/flow-positive cases were from patients with large-cell lymphomas and bulky clinical disease. Because the blood contained the same B-cell clone in 2 of 2 morphology-negative/flow-positive cases studied, blood contamination of marrow may account for these findings. Blood flow cytometric immunophenotyping studies were positive in 32 cases; 30 had marrow involvement by morphology and were from patients with follicular, mantle cell, lymphoplasmacytic, small lymphocytic, or marginal zone lymphomas. From our results, we conclude that (1) bone marrow flow cytometric immunophenotyping is not a cost-effective replacement for good morphologic evaluation in lymphoma staging and that (2) a positive peripheral blood flow cytometric immunophenotyping study when performed in low-grade lymphomas correlates with marrow involvement.
Solvent/Detergent-Treated Plasma Has Decreased Antitrypsin Activity and Absent Antiplasmin Activity
Authors: Mast Alan E. , Stadanlick Jason E. , Lockett J. Marcus , Dietzen Dennis J. 
Published: October 2019

AbstractSolvent/detergent (S/D)-treated plasma is currently marketed by the American Red Cross as a virally inactivated alternative to fresh-frozen plasma (FFP). The serpin-type serine proteinase inhibitors have a flexible reactive site loop (RSL) that can convert from the active conformation to the inactive latent or polymerized conformations when exposed to heat and/or detergents. We have compared the conformational stability and inhibitory activity of 3 plasma serpins—antithrombin, antitrypsin, and antiplasmin—in S/D plasma and FFP. In S/D plasma, virtually 100% of the antiplasmin and approximately 50% of the antitrypsin are in either the latent or polymerized conformation and lack inhibitory activity, while in FFP only the active conformation is present. Interestingly, antithrombin is not affected by S/D treatment and remains fully active. These data demonstrate that S/D plasma is not simply a virally inactivated equivalent of FFP. The lack of antiplasmin activity and decreased antitrypsin activity in S/D plasma suggest that it may not be as effective as FFP for the treatment of bleeding in patients with systemic activation of proteolytic cascades, such as disseminated intravascular coagulation and sepsis, acquired fibrinolytic states, and large-volume transfusion. Although there has been extensive use of S/D plasma in several European countries with no reports of adverse effects, clinical studies directly comparing the efficacy of these 2 plasma products are needed to directly evaluate the relative therapeutic efficacy of FFP and S/D plasma for the treatment of these diseases.
Adenovirus-Mediated Expression of Human Coagulation Factor IX in the Rhesus Macaque Is Associated With Dose-Limiting Toxicity
Authors: Lozier Jay N. , Metzger Mark E. , Donahue Robert E. , Morgan Richard A. 
Published: October 2019

AbstractWe used a first-generation adenovirus vector (AVC3FIX5) to assess whether human factor IX could be expressed and detected in the rhesus macaque, which we have shown does not make high-titer antibodies to human factor IX protein. Three animals received 1 × 1010to 1 × 1011 plaque-forming units per kilogram by intravenous injection. Human factor IX was present within 24 hours of vector administration and peaked 4 days later at 4,000 ng/mL in the high-dose recipient, and lower levels were seen in the intermediate-dose recipient. No human factor IX was detected in the low-dose recipient's plasma. Serum cytokine analysis and early hypoferremia suggested a dose-dependent acute-phase response to the vector. Human factor IX was detectable in rhesus plasma for 2 to 3 weeks for the high- and intermediate-dose recipients, but disappeared concomitant with high-titer antihuman factor IX antibody development. There was substantial, dose-dependent, dose-limiting liver toxicity that was manifest as elevated serum transaminase levels, hyperbilirubinemia, hypoalbuminemia, and prolongation of clotting times. Of particular interest was prolongation of the thrombin clotting time, an indicator of decreased fibrinogen or fibrinogen dysfunction. All evidence of liver toxicity resolved except for persistent hypofibrinogenemia in the high-dose recipient, indicating possible permanent liver damage. Our data suggest a narrow therapeutic window for first-generation adenovirus-mediated gene transfer. The development of antihuman factor IX antibodies and abnormalities of fibrinogen in the rhesus macaque is of concern for application of adenovirus (or other viral) vectors to hemophilia gene therapy.
Stromal Derived Factor-1–Induced Chemokinesis of Cord Blood CD34+ Cells (Long-Term Culture-Initiating Cells) Through Endothelial Cells Is Mediated by E-Selectin
Authors: Naiyer Afzal J. , Jo Deog-Yeon , Ahn Jongcheol , Mohle Robert , Peichev Mario , Lam George , Silverstein Roy L. , Moore Malcolm A.S. , Rafii Shahin 
Published: October 2019

AbstractHoming of hematopoietic stem cells to the bone marrow (BM) involves sequential interaction with adhesion molecules expressed on BM endothelium (BMEC) and chemokine stromal derived factor-1 (SDF-1). However, the mechanism whereby adhesion molecules regulate the SDF-1–induced transendothelial migration process is not known. E-selectin is an endothelial-specific selectin that is constitutively expressed by the BMEC in vivo. Hence, we hypothesized that E-selectin may mediate SDF-1–induced transendothelial migration of CD34+ cells. We show that CD34+ cells express both E-selectin ligand and fucosyltransferase-VII (FucT-VII). Soluble E-selectin–IgG chimera binds avidly to 75% ± 10% of CD34+ cells composed mostly of progenitors and cells with long-term culture-initiating cell (LTC-IC) potential. To assess the functional capacity of E-selectin to mediate CD34+ cell migration in a transendothelial migration system, CD34+ cells were placed on transwell plates coated with interleukin-1β–activated BMEC. In the absence of SDF-1, there was spontaneous migration of 7.0% ± 1.4% of CD34+ cells and 14.1% ± 2.2% of LTC-IC. SDF-1 induced migration of an additional 23.0% ± 4.4% of CD34+cells and 17.6% ± 3.6% of LTC-IC. Blocking MoAb to E-selectin inhibited SDF-1–induced migration of CD34+ cells by 42.0% ± 2.5% and LTC-IC by 90.9% ± 16.6%. To define the mechanism of constitutive expression of E-selectin by the BMEC in vivo, we have found that vascular endothelial growth factor (VEGF165) induces E-selectin expression by cultured endothelial cells. VEGF-stimulated endothelial cells support transendothelial migration of CD34+ cells that could be blocked by MoAb to E-selectin. These results suggest that trafficking of subsets of CD34+ cells with LTC-IC potential is determined in part by sequential interactions with E-selectin and SDF-1.
Normal Neutrophil Function in Cathepsin G-Deficient Mice
Authors: MacIvor Debra M. , Shapiro Steven D. , Pham Christine T.N. , Belaaouaj Abderazzaq , Abraham Soman N. , Ley Timothy J. 
Published: October 2019

AbstractCathepsin G is a neutral serine protease that is highly expressed at the promyelocyte stage of myeloid development. We have developed a homologous recombination strategy to create a loss-of-function mutation for murine cathepsin G. Bone marrow derived from mice homozygous for this mutation had no detectable cathepsin G protein or activity, indicating that no other protease in bone marrow cells has the same specificity. Hematopoiesis in cathepsin G−/− mice is normal, and the mice have no overt abnormalities in blood clotting. Neutrophils derived from cathepsin G−/− mice have normal morphology and azurophil granule composition; these neutrophils also display normal phagocytosis and superoxide production and have normal chemotactic responses to C5a, fMLP, and interleukin-8. Although cathepsin G has previously shown to have broad spectrum antibiotic properties, challenges of mice with Staphylococcus aureus, Klebsiella pneumoniae, or Escherichia coli yielded survivals that were not different from those of wild-type animals. In sum, cathepsin G−/− neutrophils have no obvious defects in function; either cathepsin G is not required for any of these normal neutrophil functions or related azurophil granule proteases with different specificities (ie, neutrophil elastase, proteinase 3, azurocidin, and/or others) can substitute for it in vivo.
DAR, a New RhD Variant Involving Exons 4, 5, and 7, Often in Linkage With ceAR, a New Rhce Variant Frequently Found in African Blacks
Authors: Hemker M.B. , Ligthart P.C. , Berger L. , van Rhenen D.J. , van der Schoot C.E. , Wijk P.A. Maaskant-van 
Published: October 2019

AbstractThe highly polymorphic Rh system is encoded by 2 homologous genesRHD and RHCE. Gene rearrangements, deletions, or point mutations may cause partial D and CE antigens. In this study, a newRHD variant, DAR, and a new RHCE variant, ceAR, are described in 4 Dutch African Blacks. Serologically, DAR showed weaker reactions with a monoclonal antibody and polyclonal antiserum against D. The DAR phenotype was characterized by complete loss of at least 9 of 37 Rh D epitopes. Erythrocytes expressing ceAR were all typed as VS−, V+. DNA analysis showed a partial D allele with only 3 mutations: C602G (exon 4), T667G (exon 5), and T1025C (exon 7). The ceAR allele carried G48C (exon 1), a hybrid exon 5 (A712G, C733G, A787G, and T800A), and A916G (exon 6). To study the frequency of these variants, 326 South-African Blacks was screened genomically. Of the 326 donors, 16 (4.9%) carried the DAR allele, 20 (6.1%) the ceAR allele, and 14 (4.3%) both mutated alleles. Five of these donors (1.5%) had the DAR phenotype, indicating that they carried the DAR allele homozygously or next to a D-negative allele. Immunogenicity of the D antigen for individuals with the DAR phenotype was proven, because 1 of the 4 Dutch individuals produced allo-antibodies against D after multiple transfusions with D-positive blood. In a multiethnic society, the prevalence of this D phenotype will increase and is therefore relevant in transfusion practice and in prevention of hemolytic disease of the newborn.
Correction of Uroporphyrinogen Decarboxylase Deficiency (Hepatoerythropoietic Porphyria) in Epstein-Barr Virus-Transformed B-Cell Lines by Retrovirus-Mediated Gene Transfer: Fluorescence-Based Selection of Transduced Cells
Authors: Fontanellas Antonio , Mazurier Frédéric , Moreau-Gaudry François , Belloc Francis , Ged Cécile , de Verneuil Hubert 
Published: October 2019

AbstractHepatoerythropoietic porphyria (HEP) is an inherited metabolic disorder characterized by the accumulation of porphyrins resulting from a deficiency in uroporphyrinogen decarboxylase (UROD). This autosomal recessive disorder is severe, starting early in infancy with no specific treatment. Gene therapy would represent a great therapeutic improvement. Because hematopoietic cells are the target for somatic gene therapy in this porphyria, Epstein-Barr virus-transformed B-cell lines from patients with HEP provide a model system for the disease. Thus, retrovirus-mediated expression of UROD was used to restore enzymatic activity in B-cell lines from 3 HEP patients. The potential of gene therapy for the metabolic correction of the disease was demonstrated by a reduction of porphyrin accumulation to the normal level in deficient transduced cells. Mixed culture experiments demonstrated that there is no metabolic cross-correction of deficient cells by normal cells. However, the observation of cellular expansion in vitro and in vivo in immunodeficient mice suggested that genetically corrected cells have a competitive advantage. Finally, to facilitate future human gene therapy trials, we have developed a selection system based on the expression of the therapeutic gene. Genetically corrected cells are easily separated from deficient ones by the absence of fluorescence when illuminated under UV light.