bluuebunny/crossref_metadata_2025_split huggingface dataset:
Molecular Characterization of 11q Deletions Points to a Pathogenic Role of the ATM Gene in Mantle Cell Lymphoma
Authors: Stilgenbauer Stephan , Winkler Dirk , Ott German , Schaffner Claudia , Leupolt Elke , Bentz Martin , Möller Peter , Müller-Hermelink Hans K. , James Michael R. , Lichter Peter , Döhner Hartmut 
Published: October 2019

Abstract
Deletions involving the long arm of chromosome 11 (11q) have been recently found as recurrent chromosome aberrations in mantle cell lymphoma (MCL). In the current study, the incidence and molecular extent of 11q deletions were analyzed in a series of 81 MCL by fluorescence in situ hybridization with probes from a contiguous set of yeast artificial chromosomes (YACs). Loss of chromosome 11 material was observed in 37 of 81 cases (46%). The minimally deleted segment comprised YAC 801e11 containing the ATM gene. To further narrow the minimal region of loss, P1-derived artificial chromosomes mapping to the critical region were isolated and used as probes in cases without aberrations detectable with YACs. This allowed the identification of an ATM deletion that was beyond the resolution of YAC probes. The identification of a minimally deleted segment affecting ATM suggests a pathogenic role of ATMas a tumor suppressor gene in MCL.
Expansion of human cord blood CD34+CD38−cells in ex vivo culture during retroviral transduction without a corresponding increase in SCID repopulating cell (SRC) frequency: dissociation of SRC phenotype and function
Authors: Dorrell Craig , Gan Olga I. , Pereira Daniel S. , Hawley Robert G. , Dick John E. 
Published: October 2019

AbstractCurrent procedures for the genetic manipulation of hematopoietic stem cells are relatively inefficient due, in part, to a poor understanding of the conditions for ex vivo maintenance or expansion of stem cells. We report improvements in the retroviral transduction of human stem cells based on the SCID-repopulating cell (SRC) assay and analysis of Lin− CD34+CD38−cells as a surrogate measure of stem cell function. Based on our earlier study of the conditions required for ex vivo expansion of Lin−CD34+ CD38− cells and SRC, CD34+–enriched lineage–depleted umbilical cord blood cells were cultured for 2 to 6 days on fibronectin fragment in MGIN (MSCV-EGFP-Neo) retroviral supernatant (containing 1.5% fetal bovine serum) and IL-6, SCF, Flt-3 ligand, and G-CSF. Both CD34+CD38− cells (20.8%) and CFC (26.3%) were efficiently marked. When the bone marrow of engrafted NOD/SCID mice was examined, 75% (12/16) contained multilineage (myeloid and B lymphoid) EGFP+ human cells composing as much as 59% of the graft. Half of these mice received a limiting dose of SRC, suggesting that the marked cells were derived from a single transduced SRC. Surprisingly, these culture conditions produced a large expansion (166-fold) of cells with the CD34+CD38− phenotype (n = 20). However, there was no increase in SRC numbers, indicating dissociation between the CD34+CD38− phenotype and SRC function. The underlying mechanism involved apparent downregulation of CD38 expression within a population of cultured CD34+CD38+ cells that no longer contained any SRC function. These results suggest that the relationship between stem cell function and cell surface phenotype may not be reliable for cultured cells. (Blood. 2000;95:102-110)
Novel murine myeloid cell lines that exhibit a differentiation switch in response to IL-3 or GM-CSF, or to different constitutively active mutants of the GM-CSF receptor β subunit
Authors: McCormack Matthew P. , Gonda Thomas J. 
Published: October 2019

AbstractSeveral activating mutations have recently been described in the common β subunit for the human interleukin(IL)-3, IL-5, and granulocyte-macrophage colony-stimulating factor (GM-CSF) receptors (hβc). Two of these, FIΔ and I374N, result, respectively, in a 37–amino acid duplication and an isoleucine-to-asparagine substitution in the extracellular domain. A third, V449E, leads to valine-to–glutamic acid substitution in the transmembrane domain. Previous studies have shown that when expressed in murine hemopoietic cells in vitro, the extracellular mutants can confer factor independence on only the granulocyte-macrophage lineage while the transmembrane mutant can do so to all cell types of the myeloid and erythroid compartments. To further study the signaling properties of the constitutively active hβc mutants, we have used novel murine hemopoietic cell lines, which we describe in this report. These lines, FDB1 and FDB2, proliferate in murine IL-3 and undergo granulocyte-macrophage differentiation in response to murine GM-CSF. We find that while the transmembrane mutant, V449E, confers factor-independent proliferation on these cell lines, the extracellular hβc mutants promote differentiation. Hence, in addition to their ability to confer factor independence on distinct cell types, transmembrane and extracellular activated hβc mutants deliver distinct signals to the same cell type. Thus, the FDB cell lines, in combination with activated hβc mutants, constitute a powerful new system to distinguish between signals that determine hemopoietic proliferation or differentiation. (Blood. 2000;95:120-127)
Hypoxia response element of the human vascular endothelial growth factor gene mediates transcriptional regulation by nitric oxide: control of hypoxia-inducible factor-1 activity by nitric oxide
Authors: Kimura Hideo , Weisz Alessandro , Kurashima Yukiko , Hashimoto Kouichi , Ogura Tsutomu , D'Acquisto Fulvio , Addeo Raffaelo , Makuuchi Masatoshi , Esumi Hiroyasu 
Published: October 2019

AbstractNitric oxide (NO) regulates production of vascular endothelial growth factor (VEGF) by normal and transformed cells. We demonstrate that NO donors may up-regulate the activity of the human VEGF promoter in normoxic human glioblastoma and hepatoma cells independent of a cyclic guanosine monophosphate–mediated pathway. Deletion and mutation analysis of the VEGF promoter indicates that the NO-responsive cis-elements are the hypoxia-inducible factor-1 (HIF-1) binding site and an adjacent ancillary sequence that is located immediately downstream within the hypoxia-response element (HRE). This work demonstrates that the HRE of this promoter is the primary target of NO. In addition, VEGF gene regulation by NO, as well as by hypoxia, is potentiated by the AP-1 element of the gene. Our study also reveals that NO and hypoxia induce an increase in HIF-1 binding activity and HIF-1 protein levels, both in the nucleus and the whole cell. These results suggest that there are common features of the NO and hypoxic pathways of VEGF induction, while in part, NO mediates gene transcription by a mechanism distinct from hypoxia. This is demonstrated by a difference in sensitivity to guanylate cyclase inhibitors and a different pattern of HIF-1 binding. These results show that there is a primary role for NO in the control of VEGF synthesis and in cell adaptations to hypoxia. (Blood. 2000;95:189-197)
A splice variant of human ephrin-A4 encodes a soluble molecule that is secreted by activated human B lymphocytes
Authors: Aasheim Hans-Christian , Munthe Else , Funderud Steinar , Smeland Erlend B. , Beiske Klaus , Logtenberg Ton 
Published: October 2019

AbstractEphrin-A4 is a ligand for the erythropoietin-producing hepatocellular (Eph) receptor family of tyrosine kinases. We have identified a secreted form of ephrin-A4, denoted ephrin-A4 (s), which is encoded by an alternatively spliced mRNA and is produced by in vivo activated B cells in tonsils. Blood B cells secrete ephrin-A4 (s) upon stimulation via the B-cell antigen receptor. A subpopulation of tonsil cells in the crypts with a dendritic cell phenotype was shown to express EphA2, an Eph receptor tyrosine kinase that was found to be capable of binding an ephrin-A4 immunoglobulin chimeric protein. We conclude that ephrin-A4 (s) may play a role in the interaction between activated B lymphocytes and dendritic cells in human tonsils. (Blood. 2000;95:221-230)
Application of the ELISPOT assay to the characterization of CD8+ responses to Epstein-Barr virus antigens
Authors: Yang Jie , Lemas Victor M. , Flinn Ian W. , Krone Chris , Ambinder Richard F. 
Published: October 2019

AbstractCD8+ cells have an important role in controlling Epstein-Barr virus (EBV) infection. We adapted the interferon-γ ELISPOT assay to the quantitative analysis of EBV-specific CD8+ cells. Using peripheral blood mononuclear cells (PBMCs) from healthy donors, we measured both the aggregate response to the virus, using EBV-transformed lymphoblastoid cell lines (LCLs) as stimulators, and the specific responses to 2 A2-restricted peptide epitopes: the subdominant latency membrane protein-2 (LMP2) peptide CLGGLLTMV and the early lytic BMLF1 peptide GLCTLVAML. LCL-responsive CD8+ cells were detected in all EBV-seropositive donors (range 954 to 37 830 spots/106CD8+ cells). LMP2 peptide-responsive CD8+cells were detected in 10 of 11 healthy seropositive A2 donors (range 11 to 83 spots/106 PBMC). BMLF1 peptide-responsive CD8+ cells were detected in all seropositive A2 donors examined (range 13 to 943 spots/106 PBMC). Cytotoxic T-lymphocyte (CTL) lines generated with weekly stimulation of LCLs for therapeutic purposes were also studied. Relative to PBMCs, these CTL lines showed a marked increase in the level of LCL-responsive and LMP2 peptide-responsive CD8+ cells and a lesser degree of expansion of BMLF1 peptide-responsive CD8+ cells. Finally, we applied the ELISPOT assay to monitor adoptive infusion of EBV CTL lines. In 2 patients examined, a transient increase in LCL-responsive CD8+ cells could be detected after infusion. Thus, the ELISPOT assay can be applied to the analysis of CD8+responses to EBV antigens in PBMCs, in ex vivo expanded CTL lines, and in PBMCs from patients treated with ex vivo expanded CTL lines. (Blood. 2000;95:241-248)
T-cell division in human immunodeficiency virus (HIV)-1 infection is mainly due to immune activation: a longitudinal analysis in patients before and during highly active antiretroviral therapy (HAART)
Authors: Hazenberg Mette D. , Stuart James W. T. Cohen , Otto Sigrid A. , Borleffs Jan C. C. , Boucher Charles A. B. , de Boer Rob J. , Miedema Frank , Hamann Dörte 
Published: October 2019

AbstractIn human immunodeficiency virus (HIV)-1 infection, highly increased T-cell turnover was proposed to cause exhaustion of lymphocyte production and consequently development of AIDS. Here, we investigated cell proliferation, as measured by expression of the Ki-67 nuclear antigen, in peripheral blood CD4+ and CD8+ lymphocyte subpopulations before and during highly active antiretroviral therapy (HAART). In untreated HIV-1 infection, both the percentage and number of Ki-67+CD4+ and CD8+ lymphocytes were significantly increased, compared with values obtained from healthy individuals. A more than 10-fold increase in the percentage of dividing naive CD4+ T cells in the blood was found when the number of these cells were below 100 per μL.. HAART induced an immediate decline in Ki-67 antigen expression, despite often very low CD4+ T-cell numbers, arguing against increased proliferation being a homeostatic response. After approximately 24 weeks of HAART treatment, a transient increase in the number of proliferating cells was seen, but only in the CD4+CD27+ memory pool. In the CD8+ T-cell compartment, the number of dividing cells was elevated 20- to 25-fold. This increase was most notable in the CD27+ CD 45RO+ and CD27−CD45RO+ memory CD8+ T-cell pool, corresponding with the degree of expansion of these subsets. Reduction of plasma HIV-RNA load by HAART was accompanied by a decrease in numbers and percentages of dividing cells in all CD8+T-cell subsets. Taken together, our results indicate that peripheral T-cell proliferation is a consequence of generalized immune activation. (Blood. 2000;95:249-255)
Nuclear factor-κB activation by the photochemotherapeutic agent verteporfin
Authors: Granville D. J. , Carthy C. M. , Jiang H. , Levy J. G. , McManus B. M. , Matroule J.-Y. , Piette J. , Hunt D. W. C. 
Published: October 2019

AbstractThe nuclear factor-kappa B (NF-κB) gene transactivator serves in the formation of immune, inflammatory, and stress responses. In quiescent cells, NF-κB principally resides within the cytoplasm in association with inhibitory κ (IκB) proteins. The status of IκB and NF-κB proteins was evaluated for promyelocytic leukemia HL-60 cells treated at different intensities of photodynamic therapy (PDT). The action of the potent photosensitizer, benzoporphyrin derivative monoacid ring A (verteporfin), and visible light irradiation were assessed. At a verteporfin concentration that produced the death of a high proportion of cells after light irradiation, evidence of caspase-3 and caspase-9 processing and of poly(ADP-ribose) polymerase cleavage was present within whole cell lysates. The general caspase inhibitor Z-Val-Ala-Asp-fluoromethylketone (ZVAD.fmk) effectively blocked these apoptosis-related changes. Recent studies indicate that IκB proteins may be caspase substrates during apoptosis. However, the level of IκBβ was unchanged for HL-60 cells undergoing PDT-induced apoptosis. IκB levels decreased during PDT-induced apoptosis, though ZVAD.fmk did not affect this change. At a less intensive level of photosensitization, cellular IκB levels were transiently depressed after PDT. At these times, p50 and RelA NF-κB species were increased within nuclear extracts, as revealed by electrophoretic mobility supershift assays. HL-60 cells transiently transfected with a κB-luciferase reporter construct exhibited elevated luciferase activity after PDT or treatment with tumor necrosis factor-, a well-characterized NF-κB activator. Productive NF-κB activation and associated gene transcription may influence the phenotype and behavior of cells exposed to less intensive PDT regimens. However, IκB is not subject to caspase-mediated degradation as a component of PDT-induced apoptosis. (Blood. 2000;95:256-262)
Human monocytes express functional receptors for granulocyte colony– stimulating factor that mediate suppression of monokines and interferon-γ
Authors: Boneberg Eva-Maria , Hareng Lars , Gantner Florian , Wendel Albrecht , Hartung Thomas 
Published: October 2019

AbstractIn a double-blind, placebo-controlled, randomized study, 10 healthy men received either a single dose of 480 μg granulocyte colony-stimulating factor (G-CSF) or saline. Blood taken from the volunteers was stimulated with 10 μg/mL endotoxin and released cytokines were measured by enzyme-linked immunosorbent assay. Expression of G-CSF receptors on leukocytes was examined by flow cytometry and reverse transcriptase-polymerase chain reaction. Functional activity of these receptors was tested by challenging isolated leukocyte populations to release cytokines with endotoxin in the presence of G-CSF. The G-CSF treatment attenuated the release of the proinflammatory cytokines tumor necrosis factor (TNF)-, interleukin (IL)-12, IL-1β, and interferon (IFN)-γ in ex vivo lipopolysaccharide (LPS)-stimulated whole blood. In blood from untreated volunteers the presence of G-CSF in vitro also attenuated the LPS-stimulated release of these cytokines. G-CSF in vitro also attenuated TNF- release from elutriation-purified monocytes. In the presence of 10 ng/mL recombinant TNF-, the attenuation of LPS-inducible IFN-γ release by G-CSF was blunted in whole blood. However, G-CSF had no such effect on IFN-γ release from isolated lymphocytes stimulated with anti-CD3 or a combination of TNF- and IL-12. G-CSF receptor expression was detected in human neutrophils and monocytes but not in lymphocytes by means of RT-PCR as well as flow cytometry. These results indicate that G-CSF receptors expressed on monocytes are functional in modulating monokine release. We conclude that the attenuation of IFN-γ release from lymphocytes is not a direct effect of G-CSF on these cells but is rather due to the inhibition of monocytic IL-12 and TNF- release by G-CSF. (Blood. 2000;95:270-276)
Differential expression of Rel/NF-κB and octamer factors is a hallmark of the generation and maturation of dendritic cells
Authors: Neumann M. , Fries H.-W. , Scheicher C. , Keikavoussi P. , Kolb-Mäurer A. , Bröcker E.-B. , Serfling E. , Kämpgen E. 
Published: October 2019

AbstractA key feature of maturation of dendritic cells is the down-regulation of antigen-processing and up-regulation of immunostimulatory capacities. To study the differential expression of transcription factors in this process, we investigated the nuclear translocation and DNA binding of Rel/NF-κB and octamer factors during in vitro generation and maturation of dendritic cells compared with macrophage development. RelB was the only factor strongly up-regulated during the generation of both immature dendritic cells and macrophages. Cytokine-induced maturation of dendritic cells resulted in an increase in nuclear RelB, p50, p52, and especially c-Rel, whereas cytokine-treated macrophages responded poorly. This up-regulation of NF-κB factors did not correlate with lower levels of cytosolic NF-κB inhibitors, the IκBs. One IκB, Bcl-3, was strongly expressed only in mature dendritic cells. Furthermore, generation and maturation of dendritic cells led to a continuous down-regulation of the octamer factor Oct-2, whereas monocytes and macrophages displayed high Oct-2 levels. A similar pattern of maturation-induced changes in transcription factor levels was found in cultured murine epidermal Langerhans cells, suggesting a general physiological significance of these findings. Finally, this pattern of differential activation of Rel and octamer factors appears to be suitable in determining the maturation stage of dendritic cells generated by treatment with different cytokine combinations in vitro. (Blood. 2000;95:277-285)
Evidence of increased angiogenesis in patients with acute myeloid leukemia
Authors: Hussong Jerry W. , Rodgers George M. , Shami Paul J. 
Published: October 2019

Abstract
Angiogenesis plays a key role in solid tumor growth. The purpose of this work was to study angiogenesis in acute myeloid leukemia (AML). We stained bone marrow samples from 20 adult patients with untreated AML and 20 normal controls using endothelial cell markers (ULEX-E and von Willebrand factor [vWF]). The number of vessels per millimeter length of bone marrow core biopsy specimen was scored by light microscopy. Using ULEX-E staining, AML marrows had (average ± SEM) 8.3 ± 3.6 vessels/mm (range, 3.7-19.3), whereas normal marrows had 4.3 ± 1.8 vessels/mm (range, 1.6-7.9). A similar difference was noted using vWF staining (8.6 ± 3.0 vessels/mm vs 4.9 ± 2.2 vessels/mm in AML vs normal bone marrows, respectively). The differences between the numbers of vessels/mm in AML and normal marrows were highly significant (P &lt; .0001 for both ULEX-E and vWF staining). When analyzed by FAB category, there was no difference in the average number of vessels/mm among the different subgroups of AML. Using reverse transcriptase polymerase chain reaction, we observed that the HL-60 and U937 human AML cell lines and 4 of 4 freshly isolated AML cells from untreated patients expressed mRNA for vascular endothelial growth factor (VEGF). Both cell lines as well as all fresh AML isolates tested expressed VEGF protein. Basic fibroblast growth factor was expressed only in HL-60 cells and in only 3 of 4 fresh AML samples. These observations suggest that angiogenesis may play a role in the pathogenesis of AML. Inhibition of angiogenesis could constitute a novel strategy for the treatment of AML. (Blood. 2000;95:309-313).
Genetic influences on F cells and other hematologic variables: a twin heritability study
Authors: Garner C. , Tatu T. , Reittie J. E. , Littlewood T. , Darley J. , Cervino S. , Farrall M. , Kelly P. , Spector T. D. , Thein S. L. 
Published: October 2019

Abstract
To assess the relative contribution of genetic factors in the variation of F cells (FC) and other hematologic variables, we conducted a classical twin study in unselected twins. The sample included 264 identical (monozygotic [MZ]) twin pairs and 511 nonidentical (dizygotic [DZ]) same-sex twin pairs (aged 20 to 80 years) from the St. Thomas' UK Adult Twin Register. The FC values were distributed continuously and positively skewed, with values ranging from 0.6% to 22%. FC values were higher in women than in men and decreased with age, with the variables accounting for 2% of the total FC variance. The intraclass correlations of FC values were higher in MZ (rMZ = 0.89) than in DZ (rDZ = 0.49) twins. The XmnI-Gγ polymorphism in the β-globin gene cluster had a significant effect on FC levels, accounting for approximately 13% of the total FC variance. Variance components analysis showed that the FC values were accounted for predominantly by additive genetic and nonshared environmental influences, with an estimate of heritability of 0.89. Hemoglobin levels and red blood cell, white blood cell, and platelet numbers were also substantially heritable, with heritability estimates of 0.37, 0.42, 0.62, and 0.57, respectively.
Previously, studies of sib pairs with sickle cell disease and isolated family studies showed that high levels of Hb F and FC tend to be inherited. Here, our classical twin study demonstrated that the variance of FC levels in healthy adults is largely genetically determined. (Blood. 2000;95:342-346)
Modulation of bcl-2 and p27 in human primitive proliferating hematopoietic progenitors by autocrine TGF-β1 is a cell cycle–independent effect and influences their hematopoietic potential
Authors: Pierelli Luca , Marone Maria , Bonanno Giuseppina , Mozzetti Simona , Rutella Sergio , Morosetti Roberta , Rumi Carlo , Mancuso Salvatore , Leone Giuseppe , Scambia Giovanni 
Published: October 2019

AbstractPrimitive, proliferating hematopoietic progenitors (defined as cytokine low-responding primitive progenitors; CLRPP), isolated from human CD34+ cells, expressed endoglin (CD105) and produced transforming growth factor-β1 (TGF-β1). Culture of CLRPP in serum-free conditions with anti-TGF-β1 monoclonal antibody produced a substantial decrease in bcl-2 protein/RNA levels and a significant reduction of cloning and long-term culture-initiating cell (LTC-IC) activities. GATA-1 and PU.1 RNA levels were significantly up-regulated in anti-TGF-β1–treated CLRPP, which generated an increased number of cells expressing CD15/CD11b/glycophorin-A. The described effects of TGF-β1 neutralization were observed in the absence of any relevant effect on cell cycle; number of cell divisions; p53, c-myc, and p21 RNA levels; bcl-xL and bax protein levels; and c-myc/p16/p21/p107/Rb cell cycle–related protein levels. A relevant increase in p27 protein levels was observed in anti-TGF-β1–treated CLRPP, suggesting a role for p27 in the regulation of the hematopoietic potential. The present study on human progenitors and previously reported data on TGF-β1 knockout mice suggest that, at the autocrine level, the cell cycle inhibitor TGF-β1 plays an important role in regulating the survival and differentiation of primitive proliferating hematopoietic progenitors by cell cycle–independent mechanisms.