bluuebunny/crossref_metadata_2025_split huggingface dataset:
Eicosanoid regulation of angiogenesis: role of endothelial arachidonate 12-lipoxygenase
Authors: Nie Daotai , Tang Keqin , Diglio Clement , Honn Kenneth V. 
Published: October 2019

AbstractAngiogenesis, the formation of new capillaries from preexisting blood vessels, is a multistep, highly orchestrated process involving vessel sprouting, endothelial cell migration, proliferation, tube differentiation, and survival. Eicosanoids, arachidonic acid (AA)-derived metabolites, have potent biologic activities on vascular endothelial cells. Endothelial cells can synthesize various eicosanoids, including the 12-lipoxygenase (LOX) product 12(S)-hydroxyeicosatetraenoic acid (HETE). Here we demonstrate that endogenous 12-LOX is involved in endothelial cell angiogenic responses. First, the 12-LOX inhibitor, N-benzyl-N-hydroxy-5-phenylpentanamide (BHPP), reduced endothelial cell proliferation stimulated either by basic fibroblast growth factor (bFGF) or by vascular endothelial growth factor (VEGF). Second, 12-LOX inhibitors blocked VEGF-induced endothelial cell migration, and this blockage could be partially reversed by the addition of 12(S)-HETE. Third, pretreatment of an angiogenic endothelial cell line, RV-ECT, with BHPP significantly inhibited the formation of tubelike/cordlike structures within Matrigel. Fourth, overexpression of 12-LOX in the CD4 endothelial cell line significantly stimulated cell migration and tube differentiation. In agreement with the critical role of 12-LOX in endothelial cell angiogenic responses in vitro, the 12-LOX inhibitor BHPP significantly reduced bFGF-induced angiogenesis in vivo using a Matrigel implantation bioassay. These findings demonstrate that AA metabolism in endothelial cells, especially the 12-LOX pathway, plays a critical role in angiogenesis.
Granulocyte-colony stimulating factor mobilizes T helper 2-inducing dendritic cells
Authors: Arpinati Mario , Green Cherie L. , Heimfeld Shelly , Heuser Jill E. , Anasetti Claudio 
Published: October 2019

AbstractPeripheral blood stem cells (PBSC) obtained from granulocyte-colony stimulating factor (G-CSF)-mobilized donors are increasingly used for allogeneic transplantation. Despite a 10-fold higher dose of transplanted T cells, acute graft-versus-host disease (GVHD) does not develop in higher proportion in recipients of PBSC than in recipients of marrow. T cells from G-CSF-treated experimental animals preferentially produce IL-4 and IL-10, cytokines characteristic of Th2 responses, which are associated with diminished GVHD-inducing ability. We hypothesized that G-CSF-mobilized PBSC contain antigen-presenting cells, which prime T-lymphocytes to produce Th2 cytokines. Two distinct lineages of dendritic cells (DC) have been described in humans, DC1 and DC2, according to their ability to induce naive T-cell differentiation to Th1 and Th2 effector cells, respectively. We have used multicolor microfluorometry to enumerate DC1 and DC2 in the peripheral blood of normal donors. G-CSF treatment with 10 to 16 μg/kg per day for 5 days increased peripheral blood DC2 counts from a median of 4.9 × 106/L to 24.8 × 106/L (P = .0009), whereas DC1 counts did not change. Purified DC1, from either untreated or G-CSF treated donors, induced the proliferation of allogeneic naive T cells, but fresh DC2 were poor stimulators. Tumor necrosis factor- (TNF-)-activated DC1 induced allogeneic naive T cells to produce IFN-γ, which is typical of Th1 responses, whereas TNF--activated DC2 induced allogeneic naive T cells to produce IL-4 and IL-10, which are typical of Th2 responses. PBSC transplants contained higher doses of DC2 than marrow transplants (median, 2.4 × 106/kg versus 0.5 × 106/kg) (P = .006), whereas the dose of DC1 was comparable. Thus, it is conceivable that transplantation of G-CSF-stimulated PBSC does not result in overwhelming acute GVHD because the graft contains predominantly Th2-inducing DC. Adoptive transfer of purified DC2 may be exploited to induce immune deviation after transplantation of hematopoietic stem cells or organ allografts.
Acute onset hemoglobinemia and/or hemoglobinuria and sequelae following Rho(D) immune globulin intravenous administration in immune thrombocytopenic purpura patients
Authors: Gaines Ann Reed 
Published: October 2019

AbstractRho(D) immune globulin intravenous (anti-D IGIV) was licensed by the United States Food and Drug Administration (FDA) in March 1995 to treat patients with immune thrombocytopenic purpura (ITP). Anti-D IGIV induces extravascular hemolysis, an expected adverse reaction that is consistent with the presumed mechanism of action. Between licensure and April 1999, the FDA received 15 reports of hemoglobinemia and/or hemoglobinuria following anti-D IGIV administration that met the case definition for this review. The mechanism responsible for hemoglobinemia and/or hemoglobinuria is unexplained. Review of these reports was prompted by the seriousness and the unexpectedness of treatment-associated sequelae experienced by 11 patients. Of these patients, 7 developed sufficient onset or exacerbation of anemia that orders were written for packed red blood cell transfusions, although only 6 patients were transfused. Eight patients experienced the onset or exacerbation of renal insufficiency, and 2 patients underwent dialysis. One patient died due to complications of exacerbated anemia. Six patients experienced 2 to 3 sequelae. Absent validated incidence data, a 1.5% estimated incidence rate from published clinical trial data and a 0.1% estimated reporting rate from FDA and drug utilization data were calculated for reported cases of hemoglobinemia and/or hemoglobinuria. This review presents the first case series of anti-D-IGIV–associated hemoglobinemia and/or hemoglobinuria and provides pretreatment and posttreatment clinical and laboratory findings of the case series patients. The primary purpose of this review is to increase awareness of this potentially serious occurrence among physicians and health care professionals who manage ITP patients treated with anti-D IGIV, thereby enabling prompt recognition and treatment of sequelae.
GATA-1 interacts with the myeloid PU.1 transcription factor and represses PU.1-dependent transcription
Authors: Nerlov Claus , Querfurth Erich , Kulessa Holger , Graf Thomas 
Published: October 2019

AbstractThe GATA-1 transcription factor is capable of suppressing the myeloid gene expression program when ectopically expressed in myeloid cells. We examined the ability of GATA-1 to repress the expression and function of the PU.1 transcription factor, a central regulator of myeloid differentiation. We found that GATA-1 is capable of suppressing the myeloid phenotype without interfering with PU.1 gene expression, but instead was capable of inhibiting the activity of the PU.1 protein in a dose-dependent manner. This inhibition was independent of the ability of GATA-1 to bind DNA, suggesting that it is mediated by protein-protein interaction. We examined the ability of PU.1 to interact with GATA-1 and found a direct interaction between the PU.1 ETS domain and the C-terminal finger region of GATA-1. Replacing the PU.1 ETS domain with the GAL4 DNA-binding domain removed the ability of GATA-1 to inhibit PU.1 activity, indicating that the PU.1 DNA-binding domain, rather than the transactivation domain, is the target for GATA-1–mediated repression. We therefore propose that GATA-1 represses myeloid gene expression, at least in part, through its ability to directly interact with the PU.1 ETS domain and thereby interfere with PU.1 function.
Molecular analysis of lineage-specific chimerism and minimal residual disease by RT-PCR of p210BCR-ABL and p190BCR-ABL after allogeneic bone marrow transplantation for chronic myeloid leukemia: increasing mixed myeloid chimerism and p190BCR-ABL detection precede cytogenetic relapse
Authors: Serrano Josefina , Roman Jose , Sanchez Joaquin , Jimenez Antonio , Castillejo Juan A. , Herrera Concepcion , Gonzalez Maria Gracia , Reina Luisa , Rodriguez Maria del Carmen , Alvarez Miguel A. , Maldonado Juan , Torres Antonio 
Published: October 2019

AbstractWe studied lineage-specific chimerism and minimal residual disease (MRD) in sequential posttransplant samples from 55 patients who underwent unmanipulated (n = 44) or partially T-cell–depleted (n = 11) allogeneic bone marrow transplantation (BMT) for chronic myeloid leukemia (CML). Chimerism was assessed by polymerase chain reaction (VNTR [variable number of tandem repeats]-PCR) analysis in highly purified CD19+, CD3+, CD15+, and CD56+ cell fractions, whereas MRD was investigated in whole blood by reverse transcriptase–PCR (RT-PCR) of both p210BCR-ABL and p190BCR-ABL hybrid transcripts. Of 55 patients, 14 (including 6 T-cell–depleted patients) had cytogenetic relapse at 5-80 months and progressed to hematologic relapse, while 41 patients remained in prolonged cytogenetic remission 12-107 months post-BMT. Before leukemia recurrence, patients in the relapse group showed a consistent evolution pattern sequentially featured by persistent p210BCR-ABL positivity, increasing mixed chimerism (MC) in myeloid cells, p190BCR-ABL positivity, and, finally, cytogenetic relapse. Myeloid MC preceded cytogenetic relapse by 2-12 months, whereas p190BCR/ABL was detected 1-6 months prior to cytogenetic relapse in 11 patients and concomitant with cytogenetic relapse in 3 patients. In the remission group, all patients invariably tested negative for p190BCR-ABL; 10 patients tested positive for p210BCR-ABL at variable time-points but showed persistent full donor chimerism (DC), whereas 31 patients tested p210BCR-ABL negative and displayed full DC or transient MC due to the persistence of recipient T cells. Two patients in the relapse group were successfully reinduced into molecular remission with donor lymphocyte infusion. Sequential molecular analysis after such treatment showed the inverse pattern to that observed prior to relapse, ie, progressive disappearance of p190BCR-ABL transcripts, conversion of myeloid chimerism to donor type, and, finally, p210BCR-ABL negativity. We conclude that lineage-specific chimerism and p190BCR-ABL messenger RNA (mRNA) analyses contribute a better characterization of CML evolution after BMT and enable early identification of patients at the highest risk of relapse.
MUC1 is activated in a B-cell lymphoma by the t(1;14)(q21;q32) translocation and is rearranged and amplified in B-cell lymphoma subsets
Authors: Dyomin Vadim G. , Palanisamy Nallasivam , Lloyd Kenneth O. , Dyomina Katerina , Jhanwar Suresh C. , Houldsworth Jane , Chaganti R. S. K. 
Published: October 2019

AbstractThe band 1q21 is among the most common sites affected by chromosomal translocations in lymphoid, myeloid, epithelial, and sarcomatous lesions. In non-Hodgkin's lymphoma (NHL), translocations and duplications affecting this chromosomal site are frequently, but not exclusively, seen in association with primary abnormalities such as the t(14;18)(q32;q21) and t(8;14)(q24;q32) translocations, suggesting a role for 1q21 rearrangements in tumor progression. We report here the characterization and cloning of breakpoints in a case of extranodal ascitic B-cell lymphoma with a t(1;14)(q21;q32) translocation. The breakpoints on the der(1) and der(14) chromosomes were mapped by fluorescence in situ hybridization and Southern blot analysis and cloned using an IGHG (Cγ) probe. The translocation linked theIGHG4 switch (Sγ4) sequences of the productively rearranged allele to chromosome 1 sequences downstream of MUC1, leaving the MUC1 transcriptional unit intact. MUC1 was markedly overexpressed in the tumor at the mRNA and protein levels relative to lymphoma cell lines lacking a 1q21 rearrangement. Presumably,MUC1 transcription is aberrantly regulated by the IGHA(C) 3′ enhancer element retained on the same chromosome. Screening of a panel of B-cell lymphomas by Southern blot analysis identified a subset with a 3′ MUC1 breakpoint and another with low-level amplification of MUC1. MUC-1 mucin has previously been shown to be frequently overexpressed in human epithelial cancers and to be associated with tumor progression and poor clinical outcome. Thus, MUC1 activation by chromosomal translocation, rearrangement, and amplification, identified here for the first time in NHL, is consistent with its suggested role in tumorigenesis.
The t(5;17) acute promyelocytic leukemia fusion protein NPM-RAR interacts with co-repressor and co-activator proteins and exhibits both positive and negative transcriptional properties
Authors: Redner Robert L. , Chen J. Don , Rush Elizabeth A. , Li Hui , Pollock Sheri L. 
Published: October 2019

AbstractThe t(5;17) variant of acute promyelocytic leukemia (APL) fuses the genes for nucleophosmin (NPM) and the retinoic acid receptor alpha (RAR). Two NPM-RAR molecules are expressed as a result of alternative RNA splicing. Both contain RAR sequences that encode the DNA binding, heterodimerization, and ligand activation domains of RAR. This study was designed to test the ability of these fusion proteins to act as transcriptional activators of retinoic acid responsive promoters. The NPM-RAR fusion proteins bind to retinoic acid response element sequences as either homodimers or as heterodimers with RXR. Transcription of retinoic acid–inducible promoters is activated by the fusion proteins in the presence of retinoic acid. The level of transactivation induced by the NPM-RAR fusions differs from the level of transactivation induced by wild-type RAR in both a promoter and cell specific fashion, and more closely parallels the pattern of activation of the PML-RAR fusion than wild-type RAR. In addition, NPM-RAR decreases basal transcription from some promoters and acts in a dominant-negative fashion when co-transfected with wild-type RAR. Both NPM-RAR and PML-RAR interact with the co-repressor protein SMRTe in a manner that is less sensitive than RAR to dissociation by retinoic acid. Retinoic acid induces binding of the co-activator protein RAC3. These data indicate that the NPM-RAR fusion proteins can modulate expression of retinoid-responsive genes in a positive or negative manner, depending on context of the promoter, and lend support to the hypothesis that aberrant transcriptional activation underlies the APL phenotype.
Infection of CD34+ hematopoietic progenitor cells by human herpesvirus 7 (HHV-7)
Authors: Mirandola Prisco , Secchiero Paola , Pierpaoli Sabina , Visani Giuseppe , Zamai Loris , Vitale Marco , Capitani Silvano , Zauli Giorgio 
Published: October 2019

AbstractTo investigate the tropism of the T-lymphotropic human herpesvirus 7 (HHV-7) for hematopoietic progenitors, cord blood CD34+ cells were inoculated in vitro with HHV-7 and then induced to differentiate along the granulocytic and erythroid lineages by the addition of appropriate cytokine cocktails. In semisolid assays, HHV-7 modestly affected the growth of committed (granulocytic/macrophagic and erythroid) progenitors, whereas it significantly decreased the number of pluripotent (granulocytic/erythroid/ monocytic/megakaryocytic) progenitors. Such inhibitory effect was completely abrogated by incubating HHV-7 inoculum with anti–HHV-7 neutralizing serum. In liquid cultures, HHV-7 hastened maturation along the myeloid but not the erythroid lineage, as demonstrated by the up-regulation of CD33 early myeloid antigen at day 7 of culture, and of CD15 and CD14 antigens at day 15. Moreover, HHV-7 messenger RNA was detected by reverse transcriptase–polymerase chain reaction (RT-PCR) in cells maturating along both the myeloid and the erythroid lineages. To evaluate the relevance of these in vitro findings, the presence of HHV-7 was investigated in bone marrow (BM) unfractionated mononuclear cells (MCs) as well as in purified CD34+ and CD34− cell subsets, obtained from 14 normal adult donors. HHV-7 DNA was detected by DNA-PCR in 4 of 7 BMMC samples, and it was found to be associated with both the CD34− (2 of 7) and the CD34+ (1 of 7) fractions. These data indicate that HHV-7 infects BM cells in vivo and shows the ability to affect the survival/differentiation of CD34+ hematopoietic progenitors in vitro by inhibiting more ancestral progenitors and perturbing the maturation of myeloid cells.
Sphingosine-1-phosphate and lysophosphatidic acid trigger invasion of primitive hematopoietic cells into stromal cell layers
Authors: Yanai Nobuaki , Matsui Naoko , Furusawa Tadashi , Okubo Tadashi , Obinata Masuo 
Published: October 2019

AbstractA new primitive hematopoietic cell line (THS119), exhibiting Lin−/Sca-1+/c-Kit+ a surface phenotype, grew and survived underneath stromal cells (TBR59). The ability of the THS119 cells to invade these stromal cell layers was dependent on the inclusion of serum in the culture medium. This was apparently due to a requirement for lipids contained in serum. Their invasion of the stromal cell layers in serum-free cultures could be triggered by addition of sphingosine-1-phosphate (S1P) or lysophosphatidic acid (LPA) and was dependent on both Rho- and Ras-signaling pathways. Between the 2 possible receptors of S1P and LPA, edg-1 and edg-2, expression of edg-2 only was found to be correlated with immaturity and/or invasive activity of the primitive hematopoietic cells. These results suggest the importance of specific lipids and their specific receptors on the invasive activity of primitive hematopoietic cells in the hematopoietic microenvironment.
Bactericidal/permeability-increasing protein (BPI) inhibits angiogenesis via induction of apoptosis in vascular endothelial cells
Authors: van der Schaft Daisy W. J. , Toebes Elly A. H. , Haseman Judith R. , Mayo Kevin H. , Griffioen Arjan W. 
Published: October 2019

AbstractBactericidal/permeability-increasing protein (BPI) has been known for some time to function in killing bacteria and in neutralizing the effects of bacterial endotoxin lipopolysaccharide. In the present study, BPI is found to be a novel endogenous inhibitor of angiogenesis. Within the sub-μM range, BPI shows a concentration-dependent inhibition of endothelial cell (EC) proliferation that is mediated by cell detachment and subsequent induction of apoptosis. As measured by flow cytometric analysis of the percentage of subdiploid cells, apoptosis induction was half-maximal at about 250 nmol/L BPI. Apoptosis was confirmed by quantification of cells with nuclear fragmentation. Apoptosis was found to be EC specific. In an in vitro collagen gel-based angiogenesis assay, BPI at 1.8 μmol/L inhibited tube formation by 81% after only 24 hours. Evidence for in vivo inhibition of angiogenesis was obtained, using the chorioallantoic membrane assay in which BPI was seen to be significantly effective at concentrations as low as 180 nmol/L. This newly discovered function of BPI might provide a possible therapeutic modality for the treatment of various pathologic disorders that depend on angiogenesis.
Morphological analysis of microparticle generation in heparin-induced thrombocytopenia
Authors: Hughes Mary , Hayward Catherine P. M. , Warkentin Theodore E. , Horsewood Peter , Chorneyko Katherine A. , Kelton John G. 
Published: October 2019

AbstractHeparin-induced thrombocytopenia (HIT) with thrombosis is a serious complication of heparin use. HIT sera can generate platelet-derived microparticles, which are produced in a heparin-dependent manner and are hypothesized to be important initial pathological participants because they promote vascular occlusion. To date, microparticles have been studied using flow cytometric techniques. However, it is uncertain whether the small-sized material seen in flow cytometric studies represents true platelet microparticles shed from activated platelets or whether they are platelets that have contracted after releasing their internal components. This report describes a morphological investigation of platelet-derived microparticles in HIT using, among other techniques, confocal, scanning electron, and transmission electron microscopy. Following incubation with HIT sera, the existence of small membrane-bound vesicles in the milieu of activated platelets was demonstrated. A population of microparticles, expressing platelet-specific glycoproteins, was separated from platelets by centrifugation over a sucrose layer. These microparticles had identical flow cytometric profiles, size heterogeneity, and GPIband GPIIb/IIIa staining intensity as the microparticle population in unfractionated samples. When microparticles were generated in situ and fixed onto grids, they were demonstrated to be distinct membrane-bound vesicles that originated near the platelet body and terminal ends of pseudopods on activated platelets. These microparticles appeared to be generated by localized swelling, budding, and release. Collectively, these morphological studies document the existence of true microparticles in platelets activated by HIT sera. The microparticles may play an important role in the pathogenesis of HIT.
Bcl-XL is up-regulated by HTLV-I and HTLV-II in vitro and in ex vivo ATLL samples
Authors: Nicot Christophe , Mahieux Renaud , Takemoto Shigeki , Franchini Genoveffa 
Published: October 2019

Abstract
Human T lymphotropic virus type I (HTLV-I) is the etiological agent of adult T-cell lymphocytic leukemia (ATLL), whereas HTLV-II has not been associated with hematopoietic malignancies. The control of apoptotic pathways has emerged as a critical step in the development of many cancer types. As a result, the underlying mechanism of long-term survival of HTLV-I and HTLV-II was studied in infected T cells in vitro and in ex vivo ATLL samples. Results indicate that HTLV-I– and HTLV-II–infected T cells in vitro express high levels of the antiapoptotic protein Bcl compared with other human leukemic T cell lines or uninfected peripheral blood mononuclear cells. The levels of proapoptotic proteins Bax, BAD, and Bak were not significantly altered. HTLV-I and HTLV-II viral transactivators, Tax1 and Tax2, are known to increase expression of cellular genes. These proteins were tested for increased transcription from the human Bcl2 and Bcl-XL promoters. Whereas no effect was observed on the Bcl2 promoter, both Tax1 and Tax2 increased transcription of the Bcl-XL promoter in T cells, although Tax1 appeared to be more efficient than Tax2. The biological significance of these observations was validated by the finding of an increased expression of Bcl-XL in ex vivo ATLL cells, especially from patients unresponsive to various chemotherapy regimens. Altogether, these data suggest that overexpression of Bcl-XL in vivomay be in part responsible for the resistance of ATLL cells to chemotherapy. In addition, inefficient activation of the Bcl-XL promoter by Tax2 may result in a shorter survival time of HTLV-II–infected cells in vivo and a diminished risk of leukemia development.
Novel in vitro assay for the detection of pharmacologic inducers of fetal hemoglobin
Authors: Skarpidi Evangelia , Vassilopoulos George , Li Qiliang , Stamatoyannopoulos George 
Published: October 2019

Abstract
Current techniques for identifying fetal hemoglobin (HbF) inducers are complex and time consuming. We developed a rapid and efficient method for detecting HbF inducers. Our system uses a recombinant DNA construct in which the coding sequences of 2 different luciferase reporter genes, firefly and renilla, are substituted for those of human γ and β globin genes, respectively. The activity of these genes can be distinguished by a simple, highly sensitive enzymatic assay in cell lysates. GM979 cells stably transfected with the construct are cultured in the presence of compounds, and their effects are determined by measuring the changes in activity of the 2 luciferase genes. Specific γ globin gene inducers are recognized by their ability to increase γ-firefly luciferase (γF) gene activity significantly more than β-renilla luciferase (βR) gene activity, identified by an increased ratio of γ-firefly luciferase activity over total luciferase activity. These results suggest that the use of the 2 luciferase reporter genes provides a simple, highly sensitive, and reproducible system for the detection of compounds that increase γ-globin gene expression. It can therefore be used for the screening of chemical agents that may have γ-globin gene inducibility.