Hematology Commons^™

Racial Differences In Human Platelet Par4 Reactivity Reflect Expression Of Pctp And Mir-376c., Leonard Edelstein, Lukas M Simon, Raúl Teruel Montoya, Michael Holinstat, Edward S Chen, Angela Bergeron, Xianguo Kong, Srikanth Nagalla, Narla Mohandas, David E Cohen, Jing-Fei Dong, Chad Shaw, Paul Bray

Cardeza Foundation for Hematologic Research

Racial differences in the pathophysiology of atherothrombosis are poorly understood. We explored the function and transcriptome of platelets in healthy black (n = 70) and white (n = 84) subjects. Platelet aggregation and calcium mobilization induced by the PAR4 thrombin receptor were significantly greater in black subjects. Numerous differentially expressed RNAs were associated with both race and PAR4 reactivity, including PCTP (encoding phosphatidylcholine transfer protein), and platelets from black subjects expressed higher levels of PC-TP protein. PC-TP inhibition or depletion blocked PAR4- but not PAR1-mediated activation of platelets and megakaryocytic cell lines. miR-376c levels were differentially expressed by race and …

Neuropathy, Neuropathic Pain, And Sickle Cell Disease., Samir K. Ballas, Deepika S Darbari

Cardeza Foundation for Hematologic Research

No abstract provided.

The Complex Transcriptional Landscape Of The Anucleate Human Platelet., Paul F. Bray, Steven E. Mckenzie, Leonard Edelstein, Srikanth Nagalla, Kathleen Delgrosso, Adam Ertel, Joan Kupper, Yi Jing, Eric R. Londin, Phillipe Loher, Huang-Wen Chen, Paolo Fortina, Isidore Rigoutsos

Cardeza Foundation for Hematologic Research

BACKGROUND: Human blood platelets are essential to maintaining normal hemostasis, and platelet dysfunction often causes bleeding or thrombosis. Estimates of genome-wide platelet RNA expression using microarrays have provided insights to the platelet transcriptome but were limited by the number of known transcripts. The goal of this effort was to deep-sequence RNA from leukocyte-depleted platelets to capture the complex profile of all expressed transcripts.

RESULTS: From each of four healthy individuals we generated long RNA (≥40 nucleotides) profiles from total and ribosomal-RNA depleted RNA preparations, as well as short RNA (<40 >nucleotides) profiles. Analysis of ~1 billion reads revealed that coding …

Drugs For Preventing Red Blood Cell Dehydration In People With Sickle Cell Disease., Srikanth Nagalla, Samir K Ballas

Department of Medicine Faculty Papers

BACKGROUND: Sickle cell disease is an inherited disorder of hemoglobin, resulting in abnormal red blood cells. These are rigid and may block blood vessels leading to acute painful crises and other complications. Recent research has focused on therapies to rehydrate the sickled cells by reducing the loss of water and ions from them. Little is known about the effectiveness and safety of such drugs.

OBJECTIVES: To assess the relative risks and benefits of drugs to rehydrate sickled red blood cells.

SEARCH METHODS: We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group's Haemoglobinopathies Trials Register.Last search of the Group's Trials …

Adjunct Primer For The Use Of National Comprehensive Cancer Network Guidelines For The Surgical Management Of Cutaneous Malignant Melanoma Patients., Edibaldo Silva

Journal Articles: Oncology and Hematology

Recently, a Surveillance Epidemiology and End Results (SEER) survey of melanoma patterns of care by the Mayo Clinic, Scottsdale showed remarkable deviations from best practice patterns throughout the country. The study, which analyzed the SEER records of 35,126 stage I to III cutaneous malignant melanoma patients treated from 2004 to 2006, showed that adherence to National Comprehensive Cancer Network (NCCN) therapeutic resection margins occurred in less than 36% of patients. Similarly, considerable variation in the quality of melanoma care in the United States when assessed using 26 quality indicators drawn by a panel of melanoma experts was independently reported. These …

Transfection Of Human Platelets With Short Interfering Rna., Wei Hong, Altaf A Kondkar, Srikanth Nagalla, Wolfgang Bergmeier, Ying Jin, Jay Herman, Paul Bray

Cardeza Foundation for Hematologic Research

Platelets contain mRNAs and are capable of translating mRNA into protein, and it has been previously demonstrated that platelets increase their levels of integrin β3 overtime while in blood bank storage conditions. We are unaware of prior attempts to introduce nucleic acids into platelets. Considering the potential clinical and research utility of manipulating platelet gene expression, we tested whether small interfering RNAs (siRNAs) could be transfected into normal human platelets. Multiple conditions were tested, including lipofectamine versus electroporation, different amounts of siRNA, the effect of different buffers and the presence of plasma during transfection, and the time for optimal siRNA …

Differences In Responses Of Platelets To Fluid Shear Stress In Patients With Peripheral Artery Disease (Pad) And Coronary Artery Disease (Cad)., Vijay Nambi, Kay T Kimball, Paul Bray, Angela L Bergeron, Shawna L Johnson, Joel D Morrisett, Changyi Chen, Peter H Lin, Alan B Lumsden, Christie M Ballantyne, Jing-Fei Dong

Cardeza Foundation for Hematologic Research

Information on differences in platelet function between patients with peripheral arterial disease (PAD) and patients with coronary artery disease (CAD) is limited. We sought to examine the differences in the platelets response to shear stress in patients with PAD compared to those with CAD. Men with symptomatic PAD (ankle brachial index [ABI] < 0.9; n = 29) were compared with similarly aged men with CAD (post coronary artery bypass grafting; n = 40) but without PAD. All participants were on aspirin, and none were on clopidogrel. We measured changes in shear-induced platelet aggregation (SIPA) and shear-induced P-selectin expression (SIPE) under fluid shear rates of 5000 and 10,000 s(-1)which are typically found in arterioles and stenosed arteries, respectively. Aggregation was also induced by a combined stimulation of collagen, fluid shear stress, and adenosine diphosphate (ADP) or epinephrine using a platelet function analyzer (PFA-100) as well as optical aggregometry (arachidonic acid, collagen and epinephrine). Analyses of covariance adjusted for age, aspirin dose, and statin use were used to estimate differences between the groups. Values of SIPA at fluid shear rates of 5000 and 10,000 s(-1) were significantly higher in the PAD group, while there were no differences between the PAD and CAD groups in SIPE at both fluid shear rates. However, baseline shear-induced P-selectin expression was higher in patients with PAD than CAD (mean fluorescence intensity [MFI] = 2.93 +/- 1.37 vs.1.94 +/- 0.67; p = 0.01), while the percentage increases in SIPA and SIPE at fluid shear rates of 5000 and 10,000 s(-1) were significantly higher in patients with CAD when compared to PAD (p < 0.001 for all comparisons). Although there were several similarities in platelet function between men with PAD and men with CAD, significant differences in platelet responses to shear stress were observed in men with PAD when compared to those with CAD. Although the mechanism for these observed differences are not clear, we hypothesize that in vivo platelet activation in PAD patients may contribute to the differences and will need to be further investigated.

Usefulness Of Baseline Lipids And C-Reactive Protein In Women Receiving Menopausal Hormone Therapy As Predictors Of Treatment-Related Coronary Events., Paul Bray, Joseph C Larson, Andrea Z Lacroix, Joann Manson, Marian C Limacher, Jacques E Rossouw, Norman L Lasser, William E Lawson, Marcia L Stefanick, Robert D Langer, Karen L Margolis

Cardeza Foundation for Hematologic Research

Blood lipids and high-sensitivity C-reactive protein (hs-CRP) are altered by hormone therapy. The goal of the present study was to determine whether lipids and hs-CRP have predictive value for hormone therapy benefit or risk for coronary heart disease events in postmenopausal women without previous cardiovascular disease. A nested case-control study was performed in the Women's Health Initiative hormone trials. Baseline lipids and hs-CRP were obtained from 271 incident patients with coronary heart disease (cases) and 707 controls. In a combined trial analysis, favorable lipid status at baseline tended to predict better coronary heart disease outcomes when using conjugated equine estrogen …

A New Model For Hemoglobin Ingestion And Transport By The Human Malaria Parasite Plasmodium Falciparum., Michelle D Lazarus, Timothy G Schneider, Theodore F Taraschi

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

The current model for hemoglobin ingestion and transport by intraerythrocytic Plasmodium falciparum malaria parasites shares similarities with endocytosis. However, the model is largely hypothetical, and the mechanisms responsible for the ingestion and transport of host cell hemoglobin to the lysosome-like food vacuole (FV) of the parasite are poorly understood. Because actin dynamics play key roles in vesicle formation and transport in endocytosis, we used the actin-perturbing agents jasplakinolide and cytochalasin D to investigate the role of parasite actin in hemoglobin ingestion and transport to the FV. In addition, we tested the current hemoglobin trafficking model through extensive analysis of serial …

Platelet Hyperreactivity: Predictive And Intrinsic Properties., Paul F. Bray

Cardeza Foundation for Hematologic Research

Platelet thrombi are central to the development of most vascular ischemic events. There is marked interindividual variation in platelet responsiveness, with some subjects displaying platelet hyperreactivity. An increasing number of reports indicate that there are laboratory measures of platelet function that predict clinical thrombotic events. Some, but not all, measures of platelet function are reproducible. Platelet hyperreactivity can be assessed with multiple stimuli in multiple assays and is more likely to be present in women and in subjects who have elevated fibrinogen levels.

Genome-Wide Analysis Of Neuroblastomas Using High-Density Single Nucleotide Polymorphism Arrays., Rani E George, Edward F Attiyeh, Shuli Li, Lisa A Moreau, Donna Neuberg, Cheng Li, Edward A Fox, Matthew Meyerson, Lisa Diller, Paolo Fortina, A Thomas Look, John M Maris

Cardeza Foundation for Hematologic Research

BACKGROUND: Neuroblastomas are characterized by chromosomal alterations with biological and clinical significance. We analyzed paired blood and primary tumor samples from 22 children with high-risk neuroblastoma for loss of heterozygosity (LOH) and DNA copy number change using the Affymetrix 10K single nucleotide polymorphism (SNP) array.

FINDINGS: Multiple areas of LOH and copy number gain were seen. The most commonly observed area of LOH was on chromosome arm 11q (15/22 samples; 68%). Chromosome 11q LOH was highly associated with occurrence of chromosome 3p LOH: 9 of the 15 samples with 11q LOH had concomitant 3p LOH (P = 0.016). Chromosome 1p …

Cdx4 Dysregulates Hox Gene Expression And Generates Acute Myeloid Leukemia Alone And In Cooperation With Meis1a In A Murine Model, Dimple Bansal, Claudia Scholl, Stefan Frohling, Elizabeth Mcdowell, Benjamin H. Lee, Konstanze Döhner, Patricia Ernst

Dartmouth Scholarship

HOX genes have emerged as critical effectors of leukemogenesis, but the mechanisms that regulate their expression in leukemia are not well understood. Recent data suggest that the caudal homeobox transcription factors CDX1, CDX2, and CDX4, developmental regulators of HOX gene expression, may contribute to HOX gene dysregulation in leukemia. We report here that CDX4 is expressed normally in early hematopoietic progenitors and is expressed aberrantly in approximately 25% of acute myeloid leukemia (AML) patient samples. Cdx4 regulates Hox gene expression in the adult murine hematopoietic system and dysregulates Hox genes that are implicated in leukemogenesis. Furthermore, bone marrow progenitors that …

Albumin Enhanced Morphometric Image Analysis In Cll., Matthew A. Lunning, Vincent E. Zenger, Ricardo Dreyfuss, Maryalice Stetler-Stevenson, Margaret E. Rick, Therese A. White, Wyndham H. Wilson, Gerald E. Marti

Journal Articles: Oncology and Hematology

BACKGROUND: The heterogeneity of lymphocytes from patients with chronic lymphocytic leukemia (CLL) and blood film artifacts make morphologic subclassification of this disease difficult.

METHODS: We reviewed paired blood films prepared from ethylene-diamine-tetraacetic acid (ETDA) samples with and without bovine serum albumin (BSA) from 82 CLL patients. Group 1 adhered to NCCLS specifications for the preparations of EDTA blood films. Group 2 consisted of blood films containing EDTA and a 1:12 dilution of 22% BSA. Eight patients were selected for digital photomicroscopy and statistical analysis. Approximately 100 lymphocytes from each slide were digitally captured.

RESULTS: The mean cell area +/- standard …

Induction Of Beta3-Integrin Gene Expression By Sustained Activation Of The Ras-Regulated Raf-Mek-Extracellular Signal-Regulated Kinase Signaling Pathway., Douglas Woods, Holly Cherwinski, Eleni Venetsanakos, Arun Bhat, Stephan Gysin, Martine Humbert, Paul F. Bray, Vicki L. Saylor, Martin Mcmahon

Cardeza Foundation for Hematologic Research

Alterations in the expression of integrin receptors for extracellular matrix (ECM) proteins are strongly associated with the acquisition of invasive and/or metastatic properties by human cancer cells. Despite this, comparatively little is known of the biochemical mechanisms that regulate the expression of integrin genes in cells. Here we demonstrate that the Ras-activated Raf-MEK-extracellular signal-regulated kinase (ERK) signaling pathway can specifically control the expression of individual integrin subunits in a variety of human and mouse cell lines. Pharmacological inhibition of MEK1 in a number of human melanoma and pancreatic carcinoma cell lines led to reduced cell surface expression of alpha6- and …

The Pl(A2) Polymorphism Of Integrin Beta(3) Enhances Outside-In Signaling And Adhesive Functions., K Vinod Vijayan, Pascal J. Goldschmidt-Clermont, Christine Roos, Paul F. Bray

Cardeza Foundation for Hematologic Research

Genetic factors are believed to influence the development of arterial thromboses. Because integrin alpha(IIb)beta(3) plays a crucial role in thrombus formation, we analyzed receptor adhesive properties using Chinese hamster ovary and human kidney embryonal 293 cells overexpressing the Pl(A1) or Pl(A2) polymorphic forms of alpha(IIb)beta(3). Soluble fibrinogen binding was no different between Pl(A1) and Pl(A2) cells, either in a resting state or when alpha(IIb)beta(3) was activated with anti-LIBS6. Pl(A1) and Pl(A2) cells bound equivalently to immobilized fibronectin. In contrast, significantly more Pl(A2) cells bound to immobilized fibrinogen in an alpha(IIb)beta(3)-dependent manner than did Pl(A1) cells. Disruption of the actin cytoskeleton …

Integrin-Dependent Control Of Translation: Engagement Of Integrin Alphaiibbeta3 Regulates Synthesis Of Proteins In Activated Human Platelets., Ravinder Pabla, Andrew S. Weyrich, Dan A. Dixon, Paul F. Bray, Thomas M. Mcintyre, Stephen M. Prescott, Guy A. Zimmerman

Cardeza Foundation for Hematologic Research

Integrins are widely expressed plasma membrane adhesion molecules that tether cells to matrix proteins and to one another in cell-cell interactions. Integrins also transmit outside-in signals that regulate functional responses of cells, and are known to influence gene expression by regulating transcription. In previous studies we found that platelets, which are naturally occurring anucleate cytoplasts, translate preformed mRNA transcripts when they are activated by outside-in signals. Using strategies that interrupt engagement of integrin alphaIIbbeta3 by fibrinogen and platelets deficient in this integrin, we found that alphaIIbbeta3 regulates the synthesis of B cell lymphoma 3 (Bcl-3) when platelet aggregation is induced …

Clinical Problem-Solving. Through Thick And Thin., David R. Yu, Redonda Miller, Paul F. Bray

Cardeza Foundation for Hematologic Research

No abstract provided.

Glanzmann Thrombasthenia. Cooperation Between Sequence Variants In Cis During Splice Site Selection., Ying Jin, Harry C. Dietz, Robert A. Montgomery, William R. Bell, Iain Mcintosh, Barry Coller, Paul F. Bray

Cardeza Foundation for Hematologic Research

Glanzmann thrombasthenia (GT), an autosomal recessive bleeding disorder, results from abnormalities in the platelet fibrinogen receptor, GP(IIb)-IIIa (integrin alpha(IIb)beta3). A patient with GT was identified as homozygous for a G-->A mutation 6 bp upstream of the GP(IIIa) exon 9 splice donor site. Patient platelet GP(IIIa) transcripts lacked exon 9 despite normal DNA sequence in all of the cis-acting sequences known to regulate splice site selection. In vitro analysis of transcripts generated from mini-gene constructs demonstrated that exon skipping occurred only when the G-->A mutation was cis to a polymorphism 116 bp upstream, providing precedence that two sequence variations …

A Polymorphism Of A Platelet Glycoprotein Receptor As An Inherited Risk Factor For Coronary Thrombosis., Ethan J. Weiss, Paul F. Bray, Matthew Tayback, Steven P. Schulman, Thomas S. Kickler, Lewis C. Becker, James L. Weiss, Gary Gerstenblith, Pascal J. Goldschmidt-Clermont

Cardeza Foundation for Hematologic Research

BACKGROUND: Platelet glycoprotein IIb/IIIa is a membrane receptor for fibrinogen and von Willebrand factor, and it has an important role in platelet aggregation. It is known to be involved in the pathogenesis of acute coronary syndromes. Previously, we found a high frequency of a particular polymorphism, PlA2, of the gene encoding glycoprotein IIIa in kindreds with a high prevalence of premature myocardial infarction.

METHODS: To investigate the relation between the PlA2 polymorphism and acute coronary syndromes, we conducted a case-control study of 71 case patients with myocardial infarction or unstable angina and 68 inpatient controls without known heart disease. The …

Antibodies Against Epstein-Barr Nuclear Antigen (Ebna) In Multiple Sclerosis Csf, And Two Pentapeptide Sequence Identities Between Ebna And Myelin Basic Protein., Patrick F. Bray, J Luka, Paul F. Bray, K W. Culp, J P. Schlight

Cardeza Foundation for Hematologic Research

The Epstein-Barr virus (EBV) causes infectious mononucleosis and is linked to several disparate malignancies. Prior studies on patients with multiple sclerosis (MS) showed that 100% are EBV-seropositive and that their blood contains higher antibody titers than those of controls to both transformation and lytic cycle antigens. We performed three different assays for antibodies in CSF to three major EBV antigens from patients with MS and controls. Among 93 patients with MS, 79 (85%) had CSF that reacted with a 70 kD protein, shown to be the nuclear antigen, EBNA-1, whereas only 11 (13%) of 81 EBV-seropositive controls reacted, p less …

Physical Linkage Of The Genes For Platelet Membrane Glycoproteins Iib And Iiia., Paul F. Bray, Greg Barsh, Jean-Philippe Rosa, Xue Ya Luo, Ellen Magenis, Marc A. Shuman

Cardeza Foundation for Hematologic Research

The fibrinogen receptor on human platelets is a prototypic member of the integrin family and is composed of subunit glycoproteins IIb (gpIIb) and IIIa (gpIIIa) in a 1:1 stoichiometric ratio. We have isolated cDNA clones for gpIIb and gpIIIa and localized both genes to chromosome 17. In the current study, several approaches were used to localize and map the genes for gpIIb and gpIIIa. A preliminary evaluation of subchromosomal localization was performed by using a panel of mouse-human somatic cell hybrids that contain different amounts of the long arm of human chromosome 17. Southern hybridization to the DNA of these …

Biogenesis Of The Platelet Receptor For Fibrinogen: Evidence For Separate Precursors For Glycoproteins Iib And Iiia., Paul F. Bray, Jean-Philippe Rosa, Vishwanath R. Lingappa, Yuet W. Kan, Rodger P. Mcever, Marc A. Shuman

Cardeza Foundation for Hematologic Research

Congenital absence of platelet glycoproteins IIb and IIIa (GPIIb and GPIIIa) results in a severe bleeding disorder characterized by defective platelet aggregation and failure of fibrinogen to bind to platelets. GPIIb is a two-chain protein containing disulfide-linked alpha and beta subunits. GPIIb and GPIIIa are present as a heterodimeric, noncovalent complex in the platelet plasma membrane and function as the fibrinogen receptor. To characterize synthesis of these two proteins, RNA isolated from a human leukemia cell line that contains GPIIb and GPIIIa was translated in a wheat germ cell-free system. Polyclonal antibodies specific for each protein immunoprecipitated distinct [35S]methionine-labeled precursors, …