bluuebunny/crossref_metadata_2025_split huggingface dataset:
Epstein-Barr Virus in Patients with Chronic Lymphocytic Leukemia.
Authors: Tsimberidou Apostolia-Maria , Keating Michael J. , Bueso-Ramos Carlos , Kurzrock Razelle 
Published: October 2019

Abstract
Purpose: The Epstein-Barr virus (EBV) is implicated in the development of Richter’s transformation in patients with chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma (SLL). The objective of this study was to assess the incidence and the clinical significance of EBV in patients with CLL/SLL.
Patients and Methods: Patients with CLL/SLL who presented at The University of Texas M. D. Anderson Cancer Center over a two-year period, and had available marrow paraffin blocks were studied for evidence of EBV infection using a highly specific in-situ hybridization assay for detection of EBV encoded RNA (EBERs). Results were analyzed in relation to other presenting characteristics and outcome.
Results: Thirty-two patients were examined. EBERs were detected in 12 of 32 (38%) CLL/SLL marrows versus 0 of 20 normal marrows (p = 0.002). EBERs were observed in sporadic granulocytes alone or in addition to its presence in lymphocytes in nine of the twelve EBV-positive patients. EBERs were detected less frequently in patients with Rai stage 0-1 disease (20%) compared with Rai stage 2–4 (66%; p=0.008); EBER-positive patients tended to have higher lactate dehydrogenase (LDH) levels (p=0.053). The 10-year survival rate was 22% versus 58% for patients with and without discernible EBERs (log-rank, p=0.08).
Figure Figure
Conclusions: Evidence of EBV infection was found in 38% of CLL/SLL patients assessed. Despite the small number of patients tested, discernable EBERs were significantly more common in individuals with more advanced Rai stage, and there was a trend toward shorter survival in patients in whom EBV EBERs were discerned. Larger studies are needed to determine the prognostic value and role of EBV infection in patients with CLL/SLL.
The C1542G and G505A Polymorphisms of Thrombin-Activatable Fibrinolysis Inhibitor (TAFI) in Patients with Thrombotic Microangiopathies.
Authors: Sucker Christoph , Farokhzad Firuseh , Dahhan Fieras , Schmitz Michael , Hetzel Gerd R. , Grabensee Bernd , Zotz Rainer B. , Scharf Rudiger E. 
Published: October 2019

Abstract
Background Thrombotic microangiopathies are characterized by vascular microthromboses, microangiopathic hemolytic anemia, and thrombocytopenia. Although recent research has elucidated the pathogenesis of these rare thrombotic disorders to some extent, the determinants contributing to the onset and modulating the severity are largely unknown. It is likely that risk factors of venous and arterial thrombosis also play a role in this clinical setting.
Patients and Methods In the present study, we used a case-control and a case-only design, enrolling 23 patients (mean age [± SD] 35 ± 11 years) with a history of thrombotic microangiopathy and 689 control subjects to assess the role of gene polymorphisms of the thrombin-activatable fibrinolysis inhibitor (TAFI).
Results The prevalence of the TAFI decreasing G/G genotype of the C1542G polymorphism was significantly higher in patients compared to controls (odds ratio 3.88; 95 % CI 1.07 – 11.47; p=0.02). In addition, in a case-only design the TAFI 1542 G allele was more prevalent in patients suffering from a severe course compared to those with a mild or moderate course (odds ratio 20; 95 % CI 1.85 – 216.17; p=0.009). By contrast, no such association was found for the TAFI G505A polymorphism.
Conclusions Our study shows an association of the TAFI decreasing 1542 G/G genotype with an increased risk for thrombotic microangiopathies and a more severe course. This finding might be explained by the role of TAFI as an inhibitor of local inflammatory processes.
Novel Evidence That Statin-Mediated Perturbation of Lipid Raft Formation Ameliorates Bleeding- Related Thrombocytosis.
Authors: Wysoczynski Marcin , Reca Ryan , Kucia Magda , Ratajczak Janina , Ratajczak Mariusz Z. 
Published: October 2019

Abstract
The a-chemokine stromal derived factor 1 (SDF-1) plays an important role in maturation/platelet formation of megakaryocytes (Megs), and we recently reported that the responsiveness of hematopoietic cells to SDF-1 is optimal when its corresponding CXCR4 receptor is included into membrane lipid rafts (Blood2005; 105:40). The formation of lipid rafts in vivo may be perturbed by cholesterol-lowering drugs, e.g., statins. Statins are effective in lowering LDL cholesterol and exert several pleiotropic effects on mature platelets, e.g., inhibit their activation. This latter effect is probably due to lowering of the cholesterol content in the membranes of mature platelets leading to the perturbation of membrane lipid raft formation which is required for proper platelet activation and signaling. However, under steady state conditions statins do not influence platelet production, no studies have been performed on their effects on platelet production in reactive thrombocytosis. In determining whether lipid raft formation plays a role in SDF-1- and stress-dependent thrombocytosis, we found that SDF-1 most efficiently stimulates in vitro platelet production when CXCR4 is included into membrane lipid rafts on Megs. At the molecular level, depletion of cholesterol from Megs membranes i) perturbed the responsiveness of megakaryocytic progenitors to an SDF-1 gradient, ii) inhibited SDF-1-mediated calcium flux and MAPKp42/44, AKT and STAT 1–6 phosphorylation in normal human Megs and (iii) inhibited F-actin polymerization, MMP-9 and VEGF secretion, and adhesion to endothelium and fibrinogen. More importantly we found that ex vivo-expanded human Megs, produced significantly fewer platelets during their transendothelial migration after preincubation with cholesterol-lowering MbCD. To evaluate whether cholesterol depletion from Megs affects platelet production we exposed C57Bl6 mice to statins (orally, 21 days, 750 mg/mouse) and observed that statins did not influence peripheral blood cell counts. However, when mice were acutely bled this treatment led to a significant amelioration of post-bleeding thrombocytosis as compared to untreated (control) mice. At the same time, recovery of erythrocyte and leukocyte counts was unaffected. Thus we demonstrated for the first time that statins affect CXCR4-mediated thrombopoiesis by perturbing lipid raft formation and should be considered as potential drugs to prevent post-trauma or post-operative thrombocytosis.
Inhibition of Immune Thrombocytopenic Purpura (ITP) by an Orally Bioavailable Inhibitor of Syk Kinase Activity.
Authors: Crow Andrew R. , Siragam Vinayakumar , Freedman John , Grossbard Elliott B. , Masuda Esteban S. , Pine Polly , Lazarus Alan H. 
Published: October 2019

Abstract
Immune Thrombocytopenic Purpura (ITP) is an autoimmune disease characterised by the destruction of platelets by pathogenic autoantibodies. Clearance of platelets by phagocytic cells such as macrophages occurs through activating receptors for the Fc portion of IgG (FcγR). A central tyrosine kinase in this activation pathway is Syk, which is required for FcγR-mediated phagocytosis; thus, we questioned whether inhibition of Syk would ameliorate ITP. R406 is an orally bioavailable Syk-kinase inhibitor which is well tolerated by human volunteers. Using a well-described murine model of ITP, we tested the ability of R788 (the prodrug of R406) to ameliorate thrombocytopenia. Mice injected with an antibody directed to integrin αIIβ were profoundly thrombocytopenic when platelets were enumerated 24 hr post injection. However, mice pre-treated with 25 or 40 mg/kg R788 were protected from thrombocytopenia. Mice pre-treated with the vehicle alone displayed no protection. It has been demonstrated that chimeric Syk deficient mice display a bleeding diathesis; it was therefore questioned whether treatment of mice would demonstrate prolonged tail vein bleeding time. In independent experiments, mice treated with the with the bioavailable inhibitor R406 had no significant difference in bleeding time compared to untreated mice or mice treated with vehicle alone. Syk is also involved in collagen-induced platelet secretion and aggregation. To further the potential use of this drug in humans, the ability of platelets derived from human volunteers treated with R788 to respond to in vitro collagen-induced aggregation was analysed. Platelets from volunteers treated with the drug displayed normal collagen (as well as ADP)-induced platelet aggregation compared to untreated volunteers or those treated with the vehicle alone. These data suggest that future investigation of Syk inhibition in autoimmune diseases such as ITP is warranted.
The Role of Fcγ Receptor Signaling, Tissue Factor Expression and Monocyte-Platelet Cross-Talk in the Initiation of Thrombosis by Immune Complexes.
Authors: Casasanto Peter , Reilly Michael P. , Liu Ming-Lin , Williams Kevin Jon , McKenzie Steven E. 
Published: October 2019

Abstract
Thrombus formation in response to physical disruption of the vascular endothelium is an essential response to vessel injury. In contrast, thrombus formation is pathologic when the endothelium is physically intact but blood and endothelial cells are activated by inflammation. Thrombosis secondary to immune complexes is a major cause of morbidity and mortality in hospitalized patients. We recently generated and characterized the first transgenic mouse model of heparin-induced thrombocytopenia/thrombosis (HIT/T) to recapitulate the salient features of the disease and confirmed that complexes of heparin and platelet factor 4, antibodies to the complex, and FcγRIIa-dependent platelet activation are both necessary and sufficient to model the disease in vivo. It is also likely that immune complex activation of monocytes and endothelial cells occurs in HIT/T. However, the interaction between activated blood and endothelial cells and tissue factor positive microparticles (TF+-MP) that may result in thrombin generation is not clear. Recent studies (del Conde et al., Blood 2005) showed that phosphatidylserine and PSGL-1 on the surface of monocyte-derived TF+-MP enables their fusion with activated platelets. Collagen-activated platelets incubated with TF+-MP were reported to cause increased TF-VIIa procoagulant activity (PCA) compared to non-activated platelets. We hypothesized that platelets activated by HIT/T immune complexes would also result in increased TF-PCA when incubated with monocyte-derived TF+-MP. To test this hypothesis we generated TF+-MP from THP-1 cells, a human monocytic cell line, stimulated with LPS (6 hr) and A23187 (subsequent 15 min). TF+-MPs were co-incubated with untreated or agonist-treated platelets. The HIT/T immune complex was prepared by incubating optimal ratios of heparin and recombinant human PF4 with KKO, a mouse monoclonal anti-heparin-PF4 antibody. Other agonists included anti-CD9 (producing a particulate immune complex) and collagen. Using a chromogenic assay of Xa generation we found that TF+-MPs were necessary to detect TF-PCA. PCA increased by 12–25% when TF+-MPs were incubated with platelets stimulated by collagen or anti-CD9 as compared to untreated platelets. When TF+-MPs were incubated with platelets stimulated by the HIT/T immune complex, there was a 2-fold increase in the PCA. The increase in TF-PCA was observed to be proportional to the concentration of microparticles added. The results suggest an important role in platelet-monocyte cross-talk in initiating and increasing TF procoagulant activity upon immune complex stimulation.
Gene Expression Profiling of Multiple Patients with Cyclic Thrombocytopenia Reveals Consistent Profile.
Authors: Sood Ruchira , Gourley Erin , Schrier Stanley L. , Go Ronald , Zehnder James L. 
Published: October 2019

Abstract
Cyclic thrombocytopenia (CTP) is a rare disorder characterized by periodic changes in platelet count. While some previous reports suggest an association with several cytokines, the etiology of this disorder remains poorly characterized. Using DNA microarrays, we examined the gene expression profile in peripheral whole blood at multiple time points encompassing a cycle of platelet counts from two CTP patients. We hypothesized that the variation in gene expression program in whole blood would reflect on the transcriptional changes associated with or perhaps even underlying this disease. Genome-wide cDNA microarray analysis was performed using amplified RNA obtained from 11 and 8 whole blood samples from each patient. The first patient is a 41-year old male with a 2-year history of CTP while the second patient is a 54-year old male with a 3-year history of CTP. The period of both patients’ cycles is roughly 3 weeks. No associated underlying disease has been found in both patients. With a focus on 1500 genes that change 3 fold within each group of samples we observed clusters of gene expression in whole blood that correlate with changing platelet numbers in both patients. Significant variation in expression of a cluster of interferon responsive genes during the platelet count cycle was particularly striking in both samples. Interferon (IFN) therapy is known to suppress platelet counts, and this observation suggests that aberrant IFN levels and signalling could be in part responsible for CTP. At high platelet counts, platelet transcripts were detected in whole blood RNA as inferred by high expression of previously described platelet genes including TBXAS1, TUBB1, OAZ1, SEPT5, several mitochondrial genes, NRGN and F13A1. In addition, gene clusters including known genes as well as previously uncharacterized genes were found to correlate with the peak, increasing or decreasing trends of platelet counts. Briefly, GATA2 and NFE2 expression coincided with the platelet count peak, while Tyk2 and SOCS5 expression was consistent with a rising trend of platelet counts and GATA3 and JAK2 coincided with decreasing trend of platelet counts. These results show gene expression changes associated with CTP in all cell types in whole blood and pave the way for new investigation into regulation of platelet number in a rare and fascinating disease.
Gene expression profile of whole blood of two CTP patients with platelet counts ranging from high to low and then increasing again from left to right of each panel Gene expression profile of whole blood of two CTP patients with platelet counts ranging from high to low and then increasing again from left to right of each panel
Analysis of Factors Influencing Natural Killer (NK) Cell Activity during the Early Phase after Allogeneic Stem Cell Transplantation (SCT).
Authors: Fischer Lars , Penack Olaf , Gentilini Chiara , Thiel Eckhard , Lutz Uharek 
Published: October 2019

Abstract
Background: After allogeneic SCT, NK cell mediated cytotoxicity is an important defense mechanism against residual tumor cells and viral infections. Using a novel flow cytometric assay, which detects the lytic granule membrane protein CD107a as a marker for NK cell degranulation, we investigated the effect of in vivo T cell depletion and the type of conditioning on NK cell function in the early phase after transplantation.
Methods: At day +30 and day +90 after allogeneic SCT with regular (n=14) and dose reduced conditioning (n=8), PBMCs were coincubated at 37°C for 3 h with the NK sensitive cell line HL60. 20μl of PE-Cy5 conjugated anti-CD107a monoclonal antibody (moAb) was added to each tube containing 400μl effector/target cell suspension (2x106 cells, E:T ratio 1:1) prior to incubation. After 1 hour, 10μl of monensin (2mM) was added. After incubation for 3 hours, the cells were stained with conjugated moAb (CD56, CD16, CD3) for flow cytometry. The percentage of CD107a expressing NK cells was assessed and the absolute number of degranulating NK cells /μl was calculated. Results were compared to values from 15 healthy controls.
Results: Twenty two patients (pts.) were investigated. Fourteen pts. received a conventional conditioning regimen and eight a reduced intensity conditioning. T cell depletion was applied in 15/22 pts. (ATG n=12, alemtuzumab n=2, 1 OKT-3 n=1). The type of donor included MRD (n=7) and MUD (n=15). At day +30, the proportion of NK cells with cytotoxic activity (indicated by the mean percentage of degranulating CD107a+/CD56+ cells) was significantly reduced as compared to normal donors (2.6% vs. 5.6%, p<0.001). At day +90 the percentage of degranulating NK cells was still decreased compared to normal (3.5%, p=0.007). The predominant proportion of degranulating cells was in the CD56dim/CD16− subpopulation (mean 9.8%). After conventional conditioning, the mean percentage of CD107a+ cells was 1,9% at day +30, compared to 4,0% in patients with reduced intensity conditioning (p=0.21). The absolute number of degranulating NK cells was significantly reduced after conventional conditioning (4.1/μl vs. 19.8/μl, p=0.011). Interestingly, we found no influence of in vivo T cell depletion with ATG on the mean value for CD107a+ cells at day +30 (2.5% vs. 2.9%, p=0.77).
Conclusion: Although the proportion of NK cells is increased after allogeneic SCT, our data suggest that the cytotoxic activity of these cells is considerably reduced. The absolute number of NK cells with cytotoxic activity is significantly higher after reduced intensity conditioning which may contribute to the effectiveness of these regimens. Antibody induced in vivo T cell depletion with ATG showed no impact on NK cell activity during the first two months post SCT.
Long-Term Dosing of AMG 531 Is Effective and Well Tolerated in Thrombocytopenic Patients with Immune Thrombocytopenic Purpura.
Authors: Bussel James B. , Kuter David J. , George James N. , Aledort Louis M. , Lichtin Alan E. , Lyons Roger M. , Nieva Jorge , Wasser Jeffrey S. , Bourgeois Emanuelle , Kappers-Klunne Mies , LeFrere Francois , Schipperus Martin R. , Kelly Reggie , Christal Jenny , Chen Chien-Feng , Nichol Janet L. 
Published: October 2019

Abstract
AMG 531 is a novel platelet-stimulating peptibody that targets the TPO receptor, resulting in increased production of platelets. This ongoing, open-label study assessed the safety and efficacy of long-term AMG 531 dosing in ITP patients. Eligible patients have completed a previous AMG 531 study in ITP, are ≥18 years of age, have a baseline platelet count ≤50 x 109/L, with no recent significant change in medical history. The AMG 531 starting dose is 1μg/kg by SC injection with dose adjustment to an original maximum of 30μg/kg, since reduced to 15μg/kg. Patients are treated weekly unless the platelet count is >400x109/L. Concurrent corticosteroids can be tapered when the platelet count is ≥50x109/L. Preliminary data are available for 26 patients treated for up to 24 weeks: 17 women and 9 men; mean age, 48.4±11.6 (SD) years; mean baseline platelet count, 18.5±12.3 (SD) x109/L. Twenty-one patients (80.8%) had undergone a splenectomy before study entry; 6 (23.1%) were receiving concurrent corticosteroids for ITP. Twenty-one of 26 patients (80.8%) had a protocol-defined platelet response to AMG 531 (doubling of the baseline platelet count and ≥50x109/L). The mean AMG 531 dose at the first response was 3.7±2.7 (SD) μg/kg (at median 5 weeks); the mean dose at week 24 was 7.2±4.2 (SD) μg/kg. Twelve of 26 patients (46.2%) had a durable platelet response (doubling of the baseline count and ≥50x109/L at 6 or more of weeks 17–24). Twenty patients (76.9%) had a platelet count ≥100x109/L at least once; 7 (26.9%) had a platelet count ≥400x109/L. Of 6 patients on concurrent corticosteroids, 3 discontinued treatment and 2 had a ≥25% dose reduction. At least 1 serious adverse event was reported in 4 patients: anal fistula (unrelated to treatment), adverse drug reaction (unrelated), multiple sclerosis relapse (unrelated), bone pain (related), and diffuse reticulin formation in the bone marrow reported as myelofibrosis (related). Reticulin formation is hypothesized as due to excessive accumulation of megakaryocytes in the bone marrow. AMG 531 was discontinued, and a bone marrow 3 months later showed improvement. One patient experienced adverse events (musculoskeletal pain and headache) resulting in withdrawal from the study. No neutralizing antibodies have been detected to date. In summary, repeated exposure to AMG 531 has been generally well tolerated in this ongoing study. A total 80.8% of patients achieved a platelet response, defined as doubling of the baseline count and ≥50x109/L. Individualized weekly doses of AMG 531 may provide a therapeutic option in ITP, potentially enabling patients to taper off long-term corticosteroid therapy.
Implications of RA-Induced CD38 Antigne in IFN gamma and IL-1 beta Induced Apoptosis of Endothelial Cells and Development of Retinoic Acid Syndrome.
Authors: Gao Yin , Mehta Kapil 
Published: October 2019

Abstract
Differentiation therapy of acute promyelocytic leukemia with all-trans retinoic acid (RA) represents a major advance in the treatment of myeloid leukemia. Despite high remission rates, treatment with RA is associated with the development of a unique constellation of syndromes collectively referred to as ’retinoic acid syndrome’ (RAS). RAS is characterized by fever, dyspnea, weight gain, pulmonary edema, pulmonary infiltrates, pleural and pericardial effusions, episodic hypotension, and acute renal failure, which often lead to a fatal outcome if left uncontrolled. The molecular mechanisms underlying the development of RAS, particularly the events that lead to apoptosis of endothelial cells during RAS development, remain elusive. Here, we report that RA could induce gene expressions of interferon (IFN) gamma and IL-1 beta in the peripheral blast cells of APL samples. By using human umbilical cord endothelial cells (HUVECs) and human lung microvascular endothelial cells (HLMVECs) in vitro, we observed that IFN gamma in combination with IL-1 beta exerted synergistic effect in inducing apoptosis of endothelial cells. In addition, RA treatment up-regulated the expression of CD38 antigen, an ectoenzyme involved in the metabolism of two calcium messengers, the cADPR and NAADP. RA-induced CD38 expression promoted intense attachment of maturing APL cells to the endothelial cells. Experimental data demonstrate that endothelial cells when treated with IFN gamma (10ng/ml) and IL-1 beta (10ng/ml) together undergo significant apoptosis with caspase 8 activation and CD38 expression. To our knowledge, this is the first report that demonstrates the regulation of IFN gamma gene expression in APL cells in response to RA treatment and the combined effect of cytokines and CD38 in driving endothelial cell into apoptosis. These events suggest a link between RA treatment and the development of retinoic acid syndrome and thus may offer novel approaches for controlling the development of RAS in APL patients.