bluuebunny/crossref_metadata_2025_split huggingface dataset:
Human Herpesvirus 6 (HHV-6)–Positive Burkitt's Lymphoma: Establishment of a Novel Cell Line Infected With HHV-6
Authors: Bandobashi Kentaro , Daibata Masanori , Kamioka Mikio , Tanaka Yuji , Kubonishi Ichiro , Taguchi Hirokuni , Ohtsuki Yuji , Miyoshi Isao 
Published: October 2019

AbstractHuman herpesvirus 6 (HHV-6) DNA has been detected in several human lymphoproliferative disorders. We report a case of HHV-6–infected Burkitt's lymphoma, from which a cell line, designated Katata, has been established. Katata cells had an immature B-cell phenotype with an L3 morphology and carried a t(8; 14)(q24; q32) chromosomal abnormality. The HHV-6 DNA sequences were detected in both the patient's tumor cells and Katata cell line by polymerase chain reaction using three sets of primers that target different regions of HHV-6 DNA. The presence of HHV-6 DNA in Katata cells was also shown by Southern blot hybridization with the BamHI fragment of HHV-6. It is likely that the virus is in a latent state, since (1) virion-associated protein was not expressed in Katata cells, (2) transcriptional level of the immediate-early gene was very low, and (3) no viral particles were observed by electron microscopy. Katata cells were highly tumorigenic in nude mice and the tumor cells also contained HHV-6 DNA. We have successfully obtained several clonal lines by allowing the cells to form colonies in soft agarose and by the limiting dilution method. HHV-6 DNA was detectable in all 13 clones analyzed, suggesting that virtually all Katata cells are infected with HHV-6. This is the first report of a case of HHV-6+ Burkitt's lymphoma in the absence of Epstein-Barr virus. Furthermore, there has been no report of lymphoma cell lines that are persistently and nonproductively infected with HHV-6. The Katata Burkitt's lymphoma cell line, therefore, would provide a useful tool for studies of the mechanisms of HHV-6 latency and reactivation.
Disparate Affinities of Antifolates for Folylpolyglutamate Synthetase From Human Leukemia Cells
Authors: Longo Giuseppe S.A. , Gorlick Richard , Tong William P. , Ercikan Emine , Bertino Joseph R. 
Published: October 2019

AbstractPrevious work showed that acute myelocytic leukemia blasts accumulate less long chain polyglutamates of methotrexate (MTX) than acute lymphocytic leukemia blasts when incubated with this radiolabeled antifolate. This difference likely explains the increased sensitivity of lymphoid leukemias to short-term exposure of MTX as compared with myeloid leukemias. In this study, we examined the basis for differences between long chain MTX polyglutamate accumulation between different leukemia cell types using both leukemia cell lines and blasts freshly isolated from blood of leukemic patients. The major difference found between leukemia cells that accumulate long chain polyglutamates and those that do not were differences in Km values for the enzyme folylpolyglutamate synthetase. Km values did not change with partial purification of this enzyme, indicating that interfering substances in crude lysates were not responsible for this difference. We postulate that there may be differences in the properties of this enzyme related to tissue specific expression. In contrast to MTX, both Tomudex (Zeneca Pharmaceuticals, Wilmington, DE) and 1843U89, potent inhibitors of thymidylate synthetase, have low Kms for folylpolyglutamate synthetase, and polyglutamate forms of these inhibitors are accumulated to the same degree in both myeloid and lymphoid acute leukemia cells, paralleling the equivalent cytotoxicity found between myeloid and lymphoid leukemia cell lines. Based on these results, we believe a clinical trial of Tomudex in patients with acute myeloid leukemia is warranted.
Dietary Magnesium Supplementation Ameliorates Anemia in a Mouse Model of β-Thalassemia
Authors: De Franceschi Lucia , Brugnara Carlo , Beuzard Yves 
Published: October 2019

AbstractTo ascertain the quantitative effect on the disease β-thalassemia of a low-magnesium (Mg) diet compared with a high-Mg diet and a standard-Mg diet, we studied the effect these diets had over a 4-week period on β-thalassemic (β thal) mice compared with normal C57BL/6 mice used as controls. The low-Mg diet consisted of 6 ± 2 mg Mg/kg body weight/d, the high-Mg diet 1,000 ± 20 mg Mg/kg body weight/d, and the standard-Mg diet 400 ± 20 mg Mg/kg body weight/d. β thal mice that were fed the low-Mg diet became more anemic, had reduced serum and erythrocyte Mg, and had decreased erythrocyte K. Their K-Cl cotransport increased, followed by commensurate cell dehydration. The high-Mg group showed a significant improvement of the anemia, increased serum and erythrocyte Mg, increased erythrocyte Mg, increased erythrocyte K, reduced K-Cl cotransport, and diminished cell dehydration. C57BL/6 control mice that received the low-Mg diet experienced anemia with erythrocyte dehydration, whereas the high-Mg diet had little effect on the hematologic parameters. β thal and C57BL/6 control mice that were fed a standard diet showed no changes. These results indicate that dietary Mg supplementation corrects hypomagnesemia and improves anemia in murine β thal and should be assessed in human β-thalassemia.
Outbreak of Hepatitis C Virus Infection in Patients With Hematologic Disorders Treated With Intravenous Immunoglobulins: Different Prognosis According to the Immune Status
Authors: Rossi Giuseppe , Tucci Alessandra , Cariani Elisabetta , Ravaggi Antonella , Rossini Angelo , Radaeli Enrico 
Published: October 2019

Abstract
The influence of immunodeficiency on the course of hepatitis C virus (HCV) infection is still debated, although a worsening effect has been suggested. We compared the characteristics of hepatitis C in two groups of hematologic patients with different levels of immunocompetence who acquired the same virus strain after treatment with contaminated intravenous immunoglobulins (IVIG). Indications for IVIG therapy were idiopathic thrombocytopenic purpura (ITP) in six patients and hypogammaglobulinemia in 7 patients with various hematologic disorders, who were defined immunodeficient (ID). Infection rate was 100%. Five ID patients never developed HCV antibodies despite serum HCV-RNA positivity. The same HCV genotype was shown in 10 patients tested. Moreover, E1-E2 gene partial nucleotide sequencing, performed in four patients, showed identical or closely related amino acid sequences, thus strongly supporting the hypothesis of a common source of infection. Clinical acute infection did not differ significantly between the two groups, but subsequent liver failure developed in five of the seven ID patients and in none of the ITP patients (P = .04). Liver biopsy, performed in three cases, documented HCV as the only cause of liver damage. Six ID patients died, with liver disease being the primary cause of death in four cases and a contributory cause in two cases. Their median survival after IVIG was 12 months, significantly worse than that of ITP patients (P = .0028). We conclude that immunodeficiency markedly worsens the course of IVIG-acquired HCV infection in hematologic patients.
Upregulation of the Elongation Factor-1α Gene by p53 in Association With Death of an Erythroleukemic Cell Line
Authors: Kato Mitsuo V. , Sato Hiromi , Nagayoshi Mariko , Ikawa Yoji 
Published: October 2019

AbstractGenes upregulated by p53 were screened using an erythroleukemic cell line (1-2-3) that expresses only the temperature-sensitive p53 by the mRNA differential display method. One of the upregulated genes was identified as the elongation factor-1α (EF-1α) gene, an essential component of the eukaryotic translation apparatus. Three p53-responsive elements were found in the mouse EF-1α gene and in the corresponding human, rat, and frog genes. These elements conferred the capacity for induction by p53. EF-1α is also a microtubule-severing protein. Upon the temperature-shift, the cells developed the morphology and the localization of α-tubulin similar to those of the cells treated with vincristine, a drug that affects microtubules. The microtubule-severing associated with upregulation of EF-1α by p53 may be a cause of the cell death.
Aberrations of the B-Cell Receptor B29 (CD79b) Gene in Chronic Lymphocytic Leukemia
Authors: Thompson Alexis A. , Talley Jeaniene A. , Do Ha Nancy , Kagan H. Lee , Kunkel Lori , Berenson James , Cooper Max D. , Saxon Andrew , Wall Randolph 
Published: October 2019

AbstractLeukemic B cells in chronic lymphocytic leukemia (B-CLL) typically exhibit low or undetectable surface Ig. Because the B29 (CD79b and Igβ) and mb-1 (CD79a and Igα) gene products are required for surface Ig display in the B-cell receptor complex (BCR), we analyzed the expression of these genes in B-CLL cells. The majority (83%) of the randomly selected B-CLL patient samples analyzed exhibited low or undetectable surface BCR measured by μ heavy chain and B29 expression. Levels of mb-1 mRNA in these B-CLL samples with low surface BCR were similar to those in normal B cells. Among those with decreased surface expression, B29 mRNA was not detected in half of these B-CLL samples. The remaining B-CLL samples with diminished surface BCR contained normal levels of B29 mRNA. Further analysis of cDNA clones from the majority of these latter samples contained point mutations, insertions, or deletions that were largely located in the B29 transmembrane and cytoplasmic domains. These results indicate the occurrence of somatic mutations predicted to affect B29 expression and/or function in the majority of B-CLL and suggest that these aberrations underlie the diminished surface BCR display and loss of BCR signaling characteristic of this leukemia.
Hypermethylation of the p15INK4B Gene in Myelodysplastic Syndromes
Authors: Uchida Toshiki , Kinoshita Tomohiro , Nagai Hirokazu , Nakahara Yohsuke , Saito Hidehiko , Hotta Tomomitsu , Murate Takashi 
Published: October 2019

Abstract
Previous studies have shown that the cyclin-dependent kinase inhibitor (CDKI) genes p15INK4B and p16INK4A are frequently inactivated by genetic alterations in many malignant tumors and that they are candidate tumor-suppressor genes. Although genetic alterations in these genes may be limited to lymphoid malignancies, it has been reported that their inactivation by aberrant methylation of 5′ CpG islands may be involved in various hematologic malignancies. In this study, we investigated the p15INK4B and p16INK4A genes to clarify their roles in the pathogenesis of myelodysplastic syndrome (MDS). Southern blotting analysis showed no gross genetic alterations in either of these genes. However, hypermethylation of the 5′ CpG island of the p15INK4B gene occurred frequently in patients with MDS (16/32 [50%]). Interestingly, the p15INK4B gene was frequently methylated in patients with high-risk MDS (refractory anemia with excess blasts [RAEB], RAEB in transformation [RAEB-t], and overt leukemia evolved from MDS; 14/18 [78%]) compared with patients with low-risk MDS (refractory anemia [RA] and refractory anemia with ring sideroblast [RARS]; 1/12 [8%]). Furthermore, methylation status of the p15INK4B gene was progressed with the development of MDS in most patients examined. In contrast, none of the MDS patients showed apparent hypermethylation of the p16INK4A gene. These results suggest that hypermethylation of the p15INK4B gene is involved in the pathogenesis of MDS and is one of the important late events during the development of MDS.
Marrow Transplants From Unrelated Donors for Treatment of Philadelphia Chromosome-Positive Acute Lymphoblastic Leukemia
Authors: Sierra Jorge , Radich Jerry , Hansen John A. , Martin Paul J. , Petersdorf Effie W. , Bjerke Jeanie , Bryant Eileen , Nash Richard A. , Sanders Jean E. , Storb Rainer , Sullivan Keith M. , Appelbaum Frederick R. , Anasetti Claudio 
Published: October 2019

Abstract
Transplantation of marrow from unrelated donors was investigated in patients with Philadelphia chromosome-positive (Ph1+) acute lymphoblastic leukemia (ALL) who lacked a suitable family donor. Eighteen patients underwent transplantation at our center between 1988 and 1995. The median patient age was 25 years (range, 1.7 to 51 years). Seven patients were in first complete remission, 1 in second remission, 3 in first relapse, and the remaining 7 had more advanced or chemotherapy refractory leukemia at transplant. All patients were conditioned with cyclophosphamide and total body irradiation followed by marrow transplants from closely HLA-matched, unrelated volunteers. Posttransplant graft-versus-host disease (GVHD) prophylaxis included methotrexate with either cyclosporine or FK506. Graft failure was not observed. Severe (grades III-IV) GVHD appeared in 6 of 17 evaluable patients and chronic extensive GVHD in 7 of 13 patients at risk. Five patients had recurrent ALL after transplantation and another 4 died from causes other than leukemia. Six patients transplanted in first remission, 2 in first relapse, and 1 in second remission remain alive and leukemia-free at a median follow-up of 17 months (range, 9 to 73 months). The probability of leukemia-free survival at 2 years is 49% ± 12%. These data indicate that unrelated donor marrow transplantation is an effective treatment option for patients with early stage Ph1+ ALL without a family match and suggest that in such patients an unrelated donor search should be initiated as soon as possible after diagnosis.
Novel Interaction of Apolipoprotein(a) With β-2 Glycoprotein I Mediated by the Kringle IV Domain
Authors: Köchl Silvano , Fresser Friedrich , Lobentanz Eva , Baier Gottfried , Utermann Gerd 
Published: October 2019

AbstractLipoprotein(a) [Lp(a)], which has been shown to interact with fibrin(ogen) and other components of the blood clotting cascade, is a major independent risk factor for atherothrombotic disease in humans. The physiological function(s) of Lp(a), as well as the precise mechanism(s) by which high plasma levels of Lp(a) increase risk are unknown. Identification of further potential apo(a)-protein ligands may be crucial to illuminate apo(a)'s function(s) and pathophysiological properties. We used the repetitive apo(a) kringle IV type 2, which is variable in number in apo(a), to screen a human liver cDNA library by the yeast two-hybrid interaction trap system. Among 11 positive clones that emerged from the screen, eight clones were identified as β-2 glycoprotein I and one as fibronectin. Coimmunoprecipitation experiments confirmed that β-2 glycoprotein I and apo(a)/Lp(a) interact in human plasma and in cell culture supernatants of COS-1 cells, which ectopically expressed apo(a). The apo(a)-β2-glycoprotein I interaction indicates new potential roles for Lp(a) in fibrinolysis and autoimmunity.
Interleukin-6 Downregulates Factor XII Production by Human Hepatoma Cell Line (HepG2)
Authors: Citarella Franca , Felici Angelina , Brouwer Mieke , Wagstaff John , Fantoni Antonio , Hack C. Erik 
Published: October 2019

AbstractInvolvement of the contact system of coagulation in the pathogenesis of various inflammatory diseases is suggested by reduced plasma levels of factor XII (Hageman factor) and prekallikrein generally considered to result from activation of the contact system. However, in many of these diseases patients develop an acute-phase response and, therefore, an alternative explanation for the decreased levels of factor XII could be the downregulation of factor XII gene expression in the liver as described for negative acute-phase proteins. We report here that interleukin-6 (IL-6), the principal cytokine mediating the synthesis of most acute-phase proteins in the liver, downregulates the production of factor XII by the human hepatoma cell line HepG2 by up to 75%. The decrease in protein secretion correlated with an equivalent decrease of factor XII mRNA likely indicating a pretranslational control of factor XII gene expression by IL-6. Downregulation of factor XII production by IL-6 in vitro parallelled that of transthyretin, a known negative acute-phase protein. Moreover, we show that, in patients developing an acute-phase response after immunotherapy with IL-2, plasma levels of factor XII correlate (r = .76, P < .0001) with those of transthyretin. Taken together, these results suggest that factor XII behaves as a negative acute-phase protein.
A Role for T-Helper Type-1 and Type-2 Cytokines in the Regulation of Human Monocyte Apoptosis
Authors: Estaquier Jérôme , Ameisen Jean Claude 
Published: October 2019

AbstractT-helper type-1 (Th1) and type-2 (Th2) cytokines, respectively, favor T-cell–mediated immunity and defense against intracellular pathogens or antibody-mediated immunity and defense against extracellular pathogens. Here we report that type-1 and type-2 cytokines also exert a regulatory effect on human monocyte survival. Interleukin-12 (IL-12) enhanced survival in long-term (10 days) cultures of adherent monocytes, whereas IL-10 induced death by apoptosis. In short-term cultures (2 days), the Th2 cytokines, IL-10 and IL-4, enhanced apoptosis; however, the Th1 cytokines, IL-12 and IL-2 only showed a reducing effect on monocyte apoptosis in culture conditions that decreased monocyte adhesion leading to increased levels of spontaneous apoptosis; finally, the Th1 cytokine, interferon-γ (IFN-γ), acted in a dose-dependent fashion: At high concentrations, IFN-γ enhanced apoptosis, which is an effect related to IL-10 secretion and reduced by antibodies to IL-10. Th1 cytokines reduced monocyte apoptosis induced by several stimuli: IL-2 reduced apoptosis induced by either IL-10 or high concentrations of IFN-γ, IL-12 reduced apoptosis induced by either the ligation of the Fas (CD95) molecule or γ-irradiation, and IFN-γ (at low doses that did not trigger apoptosis) reduced apoptosis induced by γ-irradiation. These findings suggest that the regulatory role of type-1 and type-2 cytokines on the development of immune responses and inflammatory reactions also involves the regulation of monocyte death by apoptosis.
Immunohistochemical Detection of the Epstein-Barr Virus–Encoded Latent Membrane Protein 2A in Hodgkin's Disease and Infectious Mononucleosis
Authors: Niedobitek G. , Kremmer E. , Herbst H. , Whitehead L. , Dawson C.W. , Niedobitek E. , von Ostau C. , Rooney N. , Grässer F.A. , Young L.S. 
Published: October 2019

AbstractWe describe two new monoclonal antibodies specific for the Epstein-Barr virus (EBV)-encoded latent membrane protein 2A (LMP2A) that are suitable for the immunohistochemical analysis of routinely processed paraffin sections. These antibodies were applied to the immunohistochemical detection of LMP2A in Hodgkin's disease (HD). LMP2A-specific membrane staining was seen in the Hodgkin and Reed-Sternberg (HRS) cells of 22 of 42 (52%) EBV-positive HD cases, but not in 39 EBV-negative HD cases. In lymphoid tissues from patients with acute infectious mononucleosis (IM), interfollicular immunoblasts were shown to express LMP2A. This is the first demonstration of LMP2A protein expression at the single-cell level in EBV-associated lymphoproliferations in vivo. The detection of LMP2A protein expression in HD and IM is of importance in view of the proposed role of this protein for maintaining latent EBV infection and its possible contribution for EBV-associated transformation. Because LMP2A provides target epitopes for EBV-specific cytotoxic T cells, the expression of this protein in HRS cells has implications for the immunotherapeutic approaches to the treatment of HD.
CD44 Regulates Hematopoietic Progenitor Distribution, Granuloma Formation, and Tumorigenicity
Authors: Schmits Rudolf , Filmus Jorge , Gerwin Nicole , Senaldi Giorgio , Kiefer Friedemann , Kundig Thomas , Wakeham Andrew , Shahinian Arda , Catzavelos Charles , Rak Janusz , Furlonger Caren , Zakarian Arsen , Simard John J.L. , Ohashi Pamela S. , Paige Christopher J. , Gutierrez-Ramos Jose C. , Mak Tak W. 
Published: October 2019

AbstractCD44 is expressed in various isoforms on numerous cell types and tissues during embryogenesis and in the mature organism. CD44 may also be involved in tumor growth. To study the multiple roles of CD44, we abolished expression of all known isoforms of CD44 in mice by targeting exons encoding the invariant N-terminus region of the molecule. Surprisingly, mice were born in Mendelian ratio without any obvious developmental or neurological deficits. Hematological impairment was evidenced by altered tissue distribution of myeloid progenitors with increased levels of colony-forming unit–granulocyte-macrophage (CFU-GM) in bone marrow and reduced numbers of CFU-GM in spleen. Fetal liver colony-forming unit–spleen and granulocyte colony-stimulating factor mobilization assays, together with reduced CFU-GM in peripheral blood, suggested that progenitor egress from bone marrow was defective. In what was either a compensatory response to CD44 deficiency or an immunoregulatory defect, mice also developed exaggerated granuloma responses to Cryotosporidium parvum infection. Finally, tumor studies showed that SV40-transformed CD44-deficient fibroblasts were highly tumorigenic in nude mice, whereas reintroduction of CD44s expression into these fibroblasts resulted in a dramatic inhibition of tumor growth.
In Vitro Senescence and Apoptotic Cell Death of Human Megakaryocytes
Authors: Zauli Giorgio , Vitale Marco , Falcieri Elisabetta , Gibellini Davide , Bassini Alessandra , Celeghini Claudio , Columbaro Marta , Capitani Silvano 
Published: October 2019

AbstractTo investigate the fate of human megakaryocytes, CD34+ hematopoietic progenitor cells were purified from the peripheral blood or bone marrow of healthy donors and seeded in serum-free chemically defined suspension cultures. In the presence of thrombopoietin (TPO; 100 ng/mL), CD34-derived cells showed an eightfold numerical expansion and a progressive maturation along the megakaryocytic lineage. Megakaryocyte maturation was characterized ultrastructurally by the presence of a demarcation membrane system and phenotypically by a high surface expression of αIIbβ3 integrin. The number of mature megakaryocytes peaked at days 12 to 15 of culture. On the other hand, the number of platelets released in the culture supernatant by CD34-derived megakaryocytes peaked at days 18 to 21, when a high percentage of megakaryocytes showed the characteristic features of apoptosis, as evaluated by electron microscopy, terminal deoxynucleotidyl transferase (TdT)-mediated d-UTP-biotin nick end-labeling technique (TUNEL) and uptake of propidium iodide. In other experiments, primary αIIbβ3+ megakaryocytic cells were directly purified from the bone marrow aspirates of normal donors and seeded in serum-free suspension cultures. In the absence of cytokines, αIIbβ3+ megakaryocytes progressively underwent apoptotic cell death. The addition of TPO but not interleukin-3 or erythropoietin showed some protection of αIIbβ3+ cells from apoptosis at early culture times (days 2 to 4), but it did not show any significant effect at later time points. These findings suggest that the terminal phase of the megakaryocyte life span is characterized by the onset of apoptosis, which can be modulated only to a certain extent by TPO.