bluuebunny/crossref_metadata_2025_split huggingface dataset:
BMP Signaling Is Crucial for Regulation Vascular Progenitor Development in Human Embryonic Stem Cells.
Authors: Wang Zack Z. , Bai Hao , Gao YongXing , Arzigian Melanie , Wojchowski Don M. , Wu Wen-shu 
Published: October 2019

Abstract
Abstract 3037
Poster Board II-1013
The generation of vascular cells from pluripotent stem cells, including human embryonic stem cells (hESCs) and induced pluripotent stem (iPS) cells, may facilitate tissue transplantation, reperfusion of ischemic tissues, and treatment of pathologies in which endothelial cell dysfunction exists. The signals that direct pluripotent stem cell differentiation into lineage-specific cells remain largely unknown. To identify vascular progenitor cells during hESC differentiation, we characterized various subpopulations that may differentiate into endothelial cells (ECs) and smooth muscle cells (SMCs). In our newly established serum-free medium, hESCs sequentially differentiated into CD34+CD31-, CD34+CD31+, and then CD34-CD31+ cells. Real-time PCR analysis indicated that EC- and SMC-specific genes, including VEGFR2, Tie2, VE-Cad, vWF, SMA, SM22-alpha, calponin, and caldesmon, were expressed significantly high in CD34+CD31+ cells. Furthermore, the CD34+CD31+ cells that were cultured in EC or SMC growth medium had high differentiation potential to become ECs and SMCs. These data suggested that CD34+CD31+ cells contain vascular progenitor cells. By treating hESCs with various factors at different time points, we found that BMP4 was critical to initiate hESC differentiation into CD34+CD31+ progenitor cells, whereas VEGF and FGF2 facilitated CD34+CD31+ cell development in the later stage. Conversely, TGFbeta promoted CD34+CD31- cells that were unable to give rise to ECs and SMCs. In addition, TGFbeta blocked the development of CD34+CD31+ cells induced by BMP4, suggesting that TGFbeta signaling negatively regulates the development of CD34+CD31+ cells during hESC differentiation. DNA microarray analysis indicated that a number of mesodermal genes were increased in BMP4-induced CD34+ cells, and a number of ectodermal genes were increased in TGFbeta-induced CD34+ cells. Therefore, the roles of BMP and TGFbeta signals in lineage differentiation may be inversely reflected in mesoderm and ectoderm. In addition, several pluripotent genes were expressed in TGFbeta-induced CD34+ cells, suggesting that TGFbeta signaling affects maintenance of stem cell pluripotency. The BMP-Smad inhibitor, dorsomorphin, inhibited phosphorylation of Smad1/5/8, and blocked hESC differentiation to CD34+CD31+ progenitor cells, suggesting that BMP Smad-dependent signaling is critical for CD34+CD31+ vascular progenitor development. Our findings provide new insight into how pluripotent hESCs differentiate to generate vascular cells.

Disclosures
No relevant conflicts of interest to declare.
High Concentrations of Thrombospondin-1 Suppress Shear Stress Induced Cleavage of Von Willebrand Factor by ADAMTS13.
Authors: Zhou Wenhua , Tsai Han-Mou 
Published: October 2019

Abstract
Abstract 3063
Poster Board II-1039
ADAMTS13 is a circulating metalloprotease that cleaves and down regulates the activity of von Willebrand factor (VWF) in the circulation. Deficiency of ADAMTS13 causes thrombotic thrombocytopenic purpura (TTP). VWF is critical for supporting platelet adhesion and aggregation at sites of microvascular injury. Nevertheless, the factors that protect VWF from cleavage by ADAMTS13 remain unknown. Thrombospondin-1 (Thbs-1), an adhesive protein that exhibit binding to multiple proteins such as collagen, fibronectin and fibrin, promotes thrombus adherence in animal models of vascular injury. To investigate the role of Thbs-1 in the regulation of VWF cleavage by ADAMTS13, we analyzed the cleavage of VWF flowing through a capillary tube. In the presence of physiological concentrations of ADAMTS13, VWF fragments were generated in a shear stress dependent manner. The cleavage of VWF in the capillary tube device was inhibited by Thbs-1 in a concentration dependent manner. At physiological concentrations (30 ng/mL) of Thbs-1, the cleavage of VWF was decreased insignificantly to 85% of control. The cleavage was decreased to 50% at 100 ng/mL Thbs-1, and to less than 10% at 1000 ng/mL Thbs-1 (P<0.0001). The suppressive effect of Thbs-1 was also observed with a truncated variant of ADAMTS13 that lacks the distal six thrombospondin type 1 repeats and the CUB domains, suggesting that the C-terminal part of ADAMTS13 is not necessary for the suppressive effect of Thbs-1. Furthermore, the presence of platelets did not negate the suppressive effect of Thbs-1 on VWF cleavage. Thbs-1 did not suppress the cleavage of FRET-VWF73 or guanidine hydrochloride treated VWF. It also did not affect the cleavage of VWF multimers induced by vortexing in the presence of ADAMTS13 and platelets. In summary, the suppressive effect of Thbs-1 on VWF cleavage is shear stress dependent. Thbs-1 is not expected to play a major role in regulating the size of circulating VWF multimers. Nevertheless, high concentrations of Thbs-1 released from platelets may protect sheared VWF from cleavage by ADAMTS13. This protective effect of Thbs-1 on VWF proteolysis may help stabilize the hemostatic plugs at sites of microvascular injury.

Disclosures
No relevant conflicts of interest to declare.
Aberrant Expression of Mir-29b, Mir-181a and Mir-181b in T-Cell Acute Lymphoblastic Leukemia.
Authors: Gimenes-Teixeira Hamilton L. , Zanette Dalila L. , dos Santos Guilherme Augusto S. , Scheucher Priscila S. , Dalmazzo Leandro F. , Araújo Amélia G. , Falcao Roberto P. , Júnior Wilson A. Silva , Rego Eduardo M 
Published: October 2019

Abstract
Abstract 3065
Poster Board III-2
Deregulations of miRNA expression and function in B-cell acute lymphoblastic leukemia (B-ALL) have been associated with specific recurrent citogenetic abnormalities and clinical outcomes. In contrast, there is few data about miRNAs in T-cell acute lymphoblastic leukemia (T-ALL). We have determined the miRNA expression profile of 48 T-ALL patients' blasts and compared with normal mature T cells. We used the Taqman MicroRNA Assay Human Panel to screen 164 known mature miRNA sequences. Normal CD3+ cells were isolated from peripheral blood of four healthy subjects by immunomagnetic labeling. Total RNA was pooled and reverse transcribed with specific looped RT primers, and expression was evaluated by quantitative real-time PCR (RQ-PCR). Reactions were performed in duplicates and samples with a coefficient of variation greater than 5% were excluded. Furthermore, we considered as differentially expressed those miRNAs with fold change values higher than 10 or lower than 0.1. With this strategy we identified four miRNAs that were hyper-expressed (miR-181a, miR-181b, miR-213 and miR-29b) and three hypo-expressed (miR-150, miR-95, miR-338) in the leukemic pool. In order to confirm our findings, we then performed the analysis of miR-181a, miR-181b and miR-29b expression on 52 individual samples (48 T-ALL and 4 normal T cell samples) using RQ-PCR. Forty-five (93.7%) and 46 (95.8%) of the T-ALL samples presented expression levels of miR-29b and of miRs 181a/181b higher than the maximum detected in the normal samples. The analysis of the predicted targets for these three miRNAs was performed using miRNApath. MAPK signaling was the pathway with the highest number of target genes with 60 genes, of which MAP4K4, FOS, RAP1B, AKT3 and NLK were commonly targeted by all three miRNAs. As deregulation of the MAPK pathway in T-ALL has been previously described, we hypothesized that the hyper-expression of miR-29b, miR-181a and miR181b may be associated with this aberrant MAPK signaling.

Disclosures
No relevant conflicts of interest to declare.
Trends in Incidence and Survival of Myeloid Malignancies Since 1980, in the Côte D'or Department, Burgundy, France.
Authors: Maynadié Marc , Manivet Ines , Mounier Morgane , Mugneret Francine , Bailly François , Caillot Denis , Petrella Tony , Flesch Michel , Carli Paule Marie , Girodon François 
Published: October 2019

Abstract
Abstract 3122
Poster Board III-59

Objective
The Registry of Haematological Malignancies (HM) has been established on January 1st, 1980 in the department of Côte d'Or (pop 500 000 inhabitants). It was the first specialized registry in haematology in the world. During the course of 25 years (1980-2004), 5026 cases of HM were recorded including 1553 Myeloid malignancies (MM) in which entities not initially considered as malignant were taken in account such as Myelodysplastic syndrome (MDS) and some Myeloproliferative neoplasms (MPN). This allow us to present trends in incidence and survival of myeloid malignancies by entities since 1980.

Method
MM diagnosed in the population between 01/01/1980 and 31/12/2004 were registered. They were coded according to ICD-O-3 and following the principles of the 2001 WHO classification i.e. new threshold of definition of acute myeloid leukaemia (AML). World population standardized incidence rate were calculated by sex, age, by urban /rural repartition and by period of time. Five-year, 10-y, 15-y and 20-y relative survival was calculated using Estève's method and based on vital status updated at the end of 2007.

Results
Incidence rate for whole MM were 3.73/100 000/y in men and 2.74 in women. They were 2.82 for AML, 3.73 in MPN and 2.83 in MDS. Sex ratio was 1.5/1 as a whole and urban/ratio was always close to 2, data being statistically significant for numerous entities. Incidence rates increase with age until 75y-o for AML and 80y-o for MPN and then decreased except for MDS in which incidence continue to increase. Along the period, only incidence of MDS increases significantly with an annual medium rate of 3% (2.7 in men and 3.3 in women). In MPN, a significant increase was observed only for women (2%). Within AML, surprisingly a significant increase was found for AML with recurrent cytogenetic abnormality in men (8.03%). 15-years relative survival was the best for MPN (46%), being significantly better in women (59% vs 31%), in which Essential Thrombocythemia was the best (74%). On the contrary, the worst 15-y survival was for was for MDS (9%). Within AML, the best survival was found for AML recurrent cytogenetic abnormalities (15-y: 54%) compare to other categories (4-8%). Survival has not increased along the period, has increased significantly in MPN. In AML, 10-y survival has increased until 1999 to reach 39% but has decreased for the 2000-2004 period (8-y: 11%).

Conclusion
Analysis of the largest epidemiologic database on HM allow to produce information such as a significant increase of incidence of MDS in which survival remained very poor in both sex, a good survival of MPN compared to other categories and a worrying decreased of survival of AML in the more recent period.

Disclosures
No relevant conflicts of interest to declare.
Parvovirus B19 Is Inactivated by Pasteurization, a Dedicated Virus Inactivation Step in the Manufacturing Process of Plasma-Derived Products.
Authors: Groener Albrecht , Nowak Thomas , Schäfer Wolfram 
Published: October 2019

Abstract
Abstract 3152
Poster Board III-89
Human parvovirus B19 (B19V), a small non-enveloped virus, is the causative agent of the childhood disease erythema infectiosum (fifth disease) but causes, especially when the disease occurs during adulthood, a number of clinical symptoms as arthralgia, arthritis, (transient) aplastic crisis, anaemia, and hydrops fetalis (during pregnancy). B19V is normally spread via the respiratory route, however, parenteral transmission can occur through blood or blood components and plasma-derived products. In order to demonstrate the safety of plasma-derived products regarding B19V, virus validation studies are performed, using usually animal parvoviruses as models for B19V which indicate that this virus is highly resistant to commonly used inactivation methods as heat. Employing a cell culture infectivity assay for B19V, established at CSL Behring's virology laboratory, a considerable higher sensitivity of B19V to pasteurization (heat treatment in aqueous solution at 60°C for 10 hours) could be demonstrated for B19V in contrast to the animal parvovirus CPV (canine parvovirus). B19V was not only very sensitive to heat in unstabilised product intermediates but also heat sensitive when studying intermediates of various plasma products containing high concentrations of the stabilizers sucrose and glycine. Although these protein stabilizers had also a stabilizing effect on B19V this virus was nevertheless considerably more sensitive to pasteurization than CPV. As shown below, pasteurization results in an effective inactivation of B19V in a wide range of plasma-derived products.
Product Mean Virus Reduction Factor [log10] due to Pasteurization B19V CPV VWF / FVIII (Humate-P) ≥3.9 1.1 FVIII (Beriate P) a ≥3.8 0.7 Fibrinogen (RiaSTAP) b ≥4.5 1.6 PCC (Beriplex P/N) a 3.5 0.5 C1-INH (Berinert P) a 3.9 1.4 Human Thrombin a 3.5 0.5 FXIII (Fibrogammin P) a ≥4.0 1.0 scIG (Vivaglobin) ≥5.0c 2.3 Human albumin (different products) ≥4.3 1.6 a product not licensed in USA b Pasteurization time 20 hours c studied in a porcine immunoglobulin intermediate to avoid neutralization by human IgG
Based on these experimental data on inactivation of B19V by pasteurization and a plasma pool for fractionation not exceeding 104 IU B19V DNA/ml, the virus safety of plasma-derived products regarding B19V can be assessed more correctly demonstrating an appropriate margin of safety.

Disclosures
Groener: CSL Behring: Employment. Nowak:CSL Behring: Employment. Schäfer:CSL Behring: Employment.
Viability and Engraftment of Hematopoietic Progenitor Cells (HPC) After Long Term Cryopreservation: Effect of Diagnosis and % Dimethylsulfoxide (DMSO) Concentration.
Authors: Veeraputhiran Muthu Kumaran , Theus John , Pesek Gina , Barlogie Bart , Cottler-Fox Michele H. 
Published: October 2019

Abstract
Abstract 3161
Poster Board III-98

Introduction
There are few reports of HPC viability after more than 9 y of storage. It has been suggested that HPC from myeloma patients (pts) may survive storage less well than those from other diseases. The appropriate concentration of DMSO for long term storage is unclear. Our program has collected and stored HPC since November 1989, changing from 5% DMSO to 10% DMSO in August 2000. We present a retrospective analysis of viability by diagnosis and DMSO concentration in pts who underwent autologous transplant using HPC after long-term storage (up to 17.8 y).

Materials and Methods
HPC were harvested and preserved using a controlled rate freezer and 5% or 10% DMSO, then stored in liquid nitrogen. Viability was tested by flow cytometry using unwashed samples and looking at propidium iodide or 7-AAD uptake within the CD34+ population. Data from 242 samples were analyzed (224 myeloma pts and 18 other diagnoses): 100 consecutively thawed samples with storage time <1 y (all 10% DMSO), 100 consecutive samples stored from 5-9 y ( 7 samples, 10% and 93 samples, 5% DMSO), and all samples stored and used for transplant after >9y (42 samples, 5% DMSO). No statistically significant difference was seen in viability between <1y and 5-9y, so these groups were combined and compared to >9y. White blood cell (WBC) and platelet engraftment were compared for the 2 groups using an unpaired t test.

Results
Mean viability for the 0-9y and >9 y groups were 91.62% and 92.79% respectively, with no statistically significant difference in viability between groups (p=0.28). Using a 2-tailed t test, no difference was seen in viability based on diagnosis (p=0.19) or between 5% and 10% DMSO (p= 0.12). No difference was seen in WBC engraftment (p=0.28) or platelet engraftment between groups (p=0.57).

Discussion
HPC collections remained viable after 17.8 years, the longest time reported for use after storage to date. No difference in viability was seen with 5% or 10% DMSO, or between myeloma and other diseases. Storage time did not affect engraftment.

Disclosures
No relevant conflicts of interest to declare.
Herpes Simplex Virus Initiates the Intrinsic Pathway of Coagulation.
Authors: Gershom Edwin S , Sutherland Michael R , Lollar Pete , Pryzdial Ed L. 
Published: October 2019

Abstract
Abstract 3173
Poster Board III-113
A hemostatic response to vascular injury is initiated by the extrinsic pathway of coagulation and amplified by the intrinsic pathway. We previously reported that purified herpes simplex virus type-1 (HSV1) has constitutive extrinsic pathway tissue factor (TF) and anionic phospholipid on its surface derived from the host cell, and can consequently bypass strict cellular control of coagulation. The current work addresses the hypothesis that HSV1-induced plasma coagulation also involves intrinsic pathway, factor VIII (FVIII), and upstream contact activation pathway, factor XII (FXII). HSV1-initiated clotting was accelerated when purified FVIII was added to FVIII-deficient plasma. The involvement of FVIII was confirmed by an inhibitory anti-FVIII antibody (Ab), which attenuated HSV1-initiated clotting of normal plasma. High HSV1 concentrations predictably reduced the effect of FVIII due to the availability of excess viral TF. To further define clotting mechanisms initiated by HSV1, the extrinsic pathway was disabled using factor VII-deficient plasma. The intrinsic pathway may be triggered by contact activation of FXII by kallikrein when bound to a suitable surface. Here we found that an inhibitor of activated FXII, corn trypsin inhibitor, and anti-FXII Ab attenuated HSV1-initiated clotting. Direct activation of purified FXII by the virus was not observed. Supporting the involvement of kallikrein in FXII activation due to HSV1, anti-kallikrein Ab was also inhibitory. The current work shows that HSV1 can trigger and amplify coagulation through the intrinsic and contact activation pathways, and suggests an additional mechanism that may explain prior reports linking virus infection to vascular pathology.

Disclosures
No relevant conflicts of interest to declare.
Immunogenicity of FVIII: a Role for Thrombin.
Authors: Skupsky Jonathan , Zhang Ai-Hong Allan , Scott David W. 
Published: October 2019

Abstract
Abstract 3175
Poster Board III-115
Administration of human Factor VIII to hemophilia A (FVIII-/-) mice is a useful small animal model to study the immune response in patients given therapeutic FVIII. These mice manifest a robust, T-cell dependent, antibody response to exogenous FVIII treatment even when encountered through traditionally tolerogenic routes, whereas a different foreign protein like ovalbumin (OVA) is much less immunogenic by these routes. Interestingly, administration of FVIII with OVA led to an immune response to both proteins, suggesting that the function of FVIII in the clotting cascade led to additional “danger” signals to co-administered proteins. Thus, we propose that FVIII is particularly immunogenic because of its function in the coagulation cascade that leads to thrombin formation. We showed that native FVIII is poorly immunogenic when it cannot activate downstream coagulation factors. Thus, heat-inactivated FVIII is poorly immunogenic despite containing normal T-cell epitopes. Importantly, native FVIII is less immunogenic in mice treated with warfarin (which blocks vitamin K-dependent enzymes) or with the direct thrombin-inhibitor, hirudin. Based on the hypothesis that thrombin generation is necessary for the immunogenicity and formation of inhibitors to FVIII, we wished to uncouple this immune response from the disease. When hemostatically normal BALB/c mice were injected directly with thrombin and OVA, they formed increased immune responses to OVA compared to mice given OVA alone. Thus, a likely mechanism is that FVIII treatment initiates a thrombin burst, which we propose is an immunogenic “danger” signal, leading indirectly to dendritic cell activation and promotion of an immune response. (Supported by NIH RO1 HL061883, NIH T32 HL007698, and AHA Fellowship 0815219E)

Disclosures
No relevant conflicts of interest to declare.
Children with NCI Standard Risk Acute Lymphoblastic Leukemia (ALL) and TEL-AML1 or Favorable Chromosome Trisomies Are Almost Certain to Be Cured with Graduated Intensity Therapy: Results of the CCG - 1991 Study.
Authors: Matloub Yousif , Bostrom Bruce C. , Angiolillo Anne L , Devidas Meenakshi , Heerema Nyla A. , Gastier-Foster Julie M. , Hunger Stephen P , Sather Harland , Linda Stephen , Carroll William L. , Nachman James B , Gaynon Paul S. 
Published: October 2019

Abstract
Abstract 320

Three thousand fifty four children with NCI standard-risk (SR) ALL were enrolled on CCG-1991; 2075 non-T ALL eligible patients were randomized and began treatment with IT cytarabine, vincristine, dexamethasone, and pegylated asparaginase. Bone marrow status was assessed at Day 7, 14, and 28 of Induction. Slow early responders (Day 7/14 M3-M3 and M3-M2; or M2 at Day 28 Induction) and patients with unfavorable cytogenetics were non-randomly assigned to a COG augmented BFM therapy regimen (N Engl J Med 1998; 338:1663).Thirteen hundred and thirty patients were analyzed for the presence of trisomy 4 and trisomy 10 (DT); and 1041 patients were evaluated for the presence of TEL/AML1 (ETV6/RUNX1) (TEL) fusion transcript. Twenty four percent of patients were positive for DT, and 41% were positive for TEL. Among the randomized subset, 23.8% had DT, and 40.8% had TEL. Six year event-free survival (EFS) and overall survival (OS) rates are given in the tables below for all patients and also separately for the randomized patients, by DT and TEL status. There was a significant different in EFS and OS between patients that were DT+ vs. DT- and also between patients that were TEL+ vs. TEL-.The overall 6-year EFS and OS for all patients with B-lineage ALL are 88.1±1.1% and 94.7±0.8%; and for the randomized patients they are 89.4±2.4% and 95.9±0.8%. We conclude that COG risk-adapted therapy is curative for patients with NCI-SR criteria and DT and/or TEL.

Disclosures:
No relevant conflicts of interest to declare.