bluuebunny/crossref_metadata_2025_split huggingface dataset:
Regulatory Mutations in GATA2 Associated with Aplastic Anemia
Authors: Townsley Danielle M. , Hsu Amy , Dumitriu Bogdan , Holland Steven M. , Young Neal S. 
Published: October 2019

Abstract
Abstract 3488
Germline heterozygous mutations in GATA2 have been reported to cause familial myelodysplasia–acute myeloid leukemia (MDS/AML), monocytopenia and mycobacterial infection (monoMAC syndrome), dendritic cell, myeloid and NK cell lymphopenia (DCML), and Emberger syndrome (lymphedema and MDS). GATA2 is a zinc finger transcription factor that plays a crucial role in regulating growth of hematopoietic progenitors. In some pedigrees, patients or family members have manifestations of bone marrow failure. We hypothesized that patients with aplastic anemia (AA) may harbor mutations in GATA2. The coding regions and regulatory regions of GATA2 were sequenced in 99 patients with confirmed AA. Sequences from 100 normal individuals as well as published human genomes from unaffected individuals (dbSNP build 135 and 1000 Genomes Project) were used as controls. Genetic variants were confirmed in hematopoietic and somatic tissues.
We identified 4 heterozygous mutations in regulatory regions of GATA2 in 5 patients. In two patients, a mutation at nucleotide 59T>G in exon 1 of isoform 2 was identified; both had severe AA in early adulthood refractory to immunosuppressive therapy. We noted this 59T>G mutation in two unrelated individuals with severe disseminated mycobacterial disease. We identified a mutation at nucleotide 20G>A in exon 2 of isoform 1, in a 3 year-old male with hepatitis-associated severe AA whose disease was refractory to multiple rounds of immunosuppressive therapy. Another mutation was present in 38G>A in exon 2 of isoform 1 in a 32 year old male with moderate AA and paroxysmal nocturnal hemoglobinuria (PNH). We also identified the exon 2 38G>A mutation in a patient with disseminated mycobacterial disease where reduced transcription of the mutant 38G>A allele was noted on RT-PCR. Finally, an intron 5, c.512+573 G>A variant was identified in an 18 year old male with severe AA who progressed after immunosuppressive therapy to MDS/AML. This variant, which causes a disruption of the FLI1 binding site, has also been found to be pathogenic in monoMAC syndrome.
In summary, a subset of patients with AA were found to have mutations in GATA2 suggesting a role for the gene in the pathogenesis of bone marrow failure. It also may identify patients at higher risk of infectious complications, those who may have less advantageous responses to immune suppression, and command earlier bone marrow transplantation.

Disclosures:
No relevant conflicts of interest to declare.
APS From the Root of Angelica Sinesis Promotes Megakaryocytopoiesis and Thrombopoiesis Through PI3k/Akt Pathway
Authors: Yang Mo , Meng Fanyi , Ye Jie Yu , Xu Yue , Xiao Bin , Chong Beng , Liu Chang 
Published: October 2019

Abstract
Abstract 4648
We have demonstrated the thrombopoietic effects of Chinese Medicine Dang Gui Bu Xue Tong (DBT), a formula composed of Radix Angelicae Sinensis and Radix Astragali in a thrombocypenic mouse model (Yang M et al, J Ethnopharm 2009). In this study, we further test the effect of polysaccharide (APS) from the root of Radix Angelicae Sinensis (APS) in in-vivo thrombopoiesis and in in-vitro megakaryocytopoiesis. A myelosuppression and thrombocytopenia mouse model was treated with APS (10 mg/kg/day), thrombopoietin (TPO) and saline as control. Peripheral blood cells from APS, TPO and vehicle-treated samples were then counted in different time-points. Using the colony-forming unit (CFU) assays, we determined the effects of APS on the hematopoietic stem/progenitor cells and megakaryocytic lineages. Analyses of Annexin V, Caspase-3, and Mitochondrial Membrane Potential were also conducted in megakaryocytic cell line M-07e. Lastly, the effects of APS on cells treated with Ly294002, a Phosphatidylinositol 3-Kinse inhibitor and the effect of APS on the phosphorylation of AKT were further studied in megakaryocytic cells. Our results showed that APS significantly enhanced the platelets and other blood cells recovery and CFU formation in this model. Morphological examination of bone marrows showed that APS treatment significantly increased the recovery of the megakaryocytic series and other hematopoietic progenitor cells. We observed the antiapoptotic effects of APS on M-07e cells. Addition of Ly294002 alone increases the percentage of cells undergoing apoptosis. In contrast, additional of APS to Ly294002-treated cells reversed the percentage of cells undergoing apoptosis. Furthermore, addition of APS significantly increased the phosphorylation of AKT. Our studies demonstrate that APS promotes platelet recovery in the mouse model and has anti-apoptosis effect in megakaryocytic cells. This effect is likely to be mediated by the PI3K/AKT pathway.

Disclosures:
No relevant conflicts of interest to declare.
Effects of Small-Molecule Inhibitors of TNFR2 Signaling Pathways On TNF-Mediated Expansion of CD4+FoxP3+ Regulatory T Cells
Authors: Wu Xueqiang , Chen Yan , Han Chunsheng , Gong Yiwen , Bu Dingfang , Zhang Yin , Xia Junyan , Liu Qian , Chen Xue , Hu Yang , Zhu Ping 
Published: October 2019

Abstract
Abstract 4722
TNF is a pleiotropic cytokine with biphasic proinflammatory and immunosuppressive effects. Previous work clearly demonstrated that TNF has the capacity to preferentially activate and promote the proliferative expansion of CD4+FoxP3+ regulatory T cells (Tregs), which represent a basis for the paradoxical anti-inflammatory action of TNF. Our studies also indicate that TNFR2, one of the TNF receptor which is preferentially expressed by Tregs, mediates the Treg-activating effect of TNF. However, the molecular mechanism and signaling pathways mediated Treg-activating effect of TNF remain to be understood.
In this study, we first further verified that TNFR2 transduces the activating signal of TNF on Tregs, based on the evidence that 1) human TNF, known to only bind to mouse TNFR1, did not activate mouse Tregs; 2) a blocking anti mouse TNFR2 Ab, but not TNFR1 Ab, dose-dependently inhibited TNF-mediated proliferation of mouse Tregs at concentrations of 2.5–500 ng/ml. We next examined the signaling pathways of TNFR2 leading to the proliferation of Tregs, by using specific small-molecule inhibitors. It is well established that the activation of IKK-NFkB is a major consequence of activation of TNFR2. However, small molecule inhibitors of NFkB signaling pathway, namely BAY11–7082 and Sulfasalazine, did not block TNF-mediated proliferation of Tregs. In contrast, small molecule inhibitors of MAPK signaling pathway, SB203580 (P38 MAPK inhibitor), SP600125 (JNK inhibitor) and PD98059 (Erk1/2 inhibitor), potently suppressed TNF-induced replication of Tregs in a dose-dependent manner.
Our results indicate that TNF selectively stimulates the expansion of FoxP3+ Tregs through TNFR2. Activation of MAPK (ERK1/2,P38 and JNK), rather than NFkB, is responsible for this activity of TNF.

Disclosures:
No relevant conflicts of interest to declare.
Preclinical Data In Cynomolgus (cyn) Monkeys Of ASTX727, a Novel Oral Hypomethylating Agent (HMA) Composed Of Low-Dose Oral Decitabine Combined With a Novel Cytidine Deaminase Inhibitor (CDAi) E7727
Authors: Oganesian Aram , Redkar Sanjeev , Taverna Pietro , Joshi-Hangal Rajashree , Azab Mohammad 
Published: October 2019

Abstract

Background
Hypomethylating agents (HMAs) such as decitabine and azacitidine have been successfully used in the clinic to treat hematological malignancies by parenteral administration (IV or SC). Due to low oral bioavailability of these agents, relatively high doses are required to achieve therapeutic systemic exposures by the oral route. Higher oral doses can be associated with significant GI toxicities due to intestinal enterocytes being exposed to high concentrations of these agents in the lumen. One of the main factors contributing to low oral bioavailability of HMAs is the high first-pass effect due to cytidine deaminase in GI and liver.

Methods
In this study, E7727, a novel CDA inhibitor (CDAi) was combined with decitabine (3 mg/kg) for oral administration in cynomolgus (cyn) monkeys at E7727 doses of 0.1-10 mg/kg.

Results
Systemic AUC exposures for decitabine increased from 21.7 ng*hr/mL (without E7727) to as high as 1,494 ng*hr/mL at 10mg/kg E7727. At a dose combination of 1 mg/kg CDAi and 3 mg/kg decitabine (corresponding to a human equivalent dose of 36 mg/m2), AUC exposures were 301±94 ng*hr/mL, which are slightly higher than the published clinical therapeutic range after decitabine IV infusion of 20 mg/m2 (115-220 ng*hr/mL), suggesting that a combination approach for oral CDAi+decitabine is feasible to achieve required clinical exposures at a range of relatively low-dose(s). In addition, the concentration-time profile of decitabine when combined with CDAi resembled that achieved with IV decitabine over 1 hour infusion. The effect of drug-drug interaction between CDAi and decitabine was modeled based on a relationship between CDAi Ki (∼ 0.14 µM based on IC50) and Cmaxlevels and appeared to predict the observed fold-increases in decitabine AUC with high concordance. In addition, low dose oral decitabine+CDAi achieved decitabine exposures that produce potent hypomethylation as observed by LINE-1 assay.

Conclusion
Pronounced increase in oral decitabine exposures was achieved when combined with the novel CDA inhibitor E7727. Cyn monkeys appear to be a relevant model for human PK based on similar background of circulating serum cytidine levels reflective of similar CDA status between humans and cyn monkeys. These data support the initiation of clinical First in Human (FIH) study of ASTX727, a novel oral HMA combining oral decitabine with the CDAi E7727.

Disclosures:
Oganesian: Astex Pharmaceuticals: Employment. Redkar:Astex Pharmaceuticals: Employment. Taverna:Astex Pharmaceuticals Inc.: Employment. Joshi-Hangal:Astex Pharmaceuticals, Inc.: Employment. Azab:Astex Pharmaceuticals Inc.: Employment.
LY2928057, An Antibody Targeting Ferroportin, Is a Potent Inhibitor Of Hepcidin Activity and Increases Iron Mobilization In Normal Cynomolgus Monkeys
Authors: Witcher Derrick R , Leung Donmienne , Hill Karen A , De Rosa David C , Xu Jianghuai , Manetta Joseph , Wroblewski Victor J , Benschop Robert J 
Published: October 2019

Abstract
Hepcidin, a 25-amino acid peptide hormone which is primarily synthesized and secreted from the liver, is a key regulator of iron homeostasis. It regulates dietary iron absorption, plasma iron concentrations, and tissue iron distribution through interactions with ferroportin, the only known mammalian cellular iron exporter. Hepcidin induces the internalization and subsequent degradation of ferroportin. The reduction in iron release caused by the loss of ferroportin, combined with the continuing demand for iron by erythropoietic precursors, results in a decrease in circulating iron levels. Dysregulation of the hepcidin-ferroportin axis contributes to the pathogenesis of different anemias. Decreased synthesis of hepcidin may cause systemic iron overload in iron-loading anemias such as beta-thalassemia; whereas overproduction of hepcidin may contribute to the development of anemia in inflammatory disorders, malignancies, and chronic kidney disease. LY2928057 is a novel humanized IgG4 monoclonal antibody that binds to human ferroportin with a high affinity, blocks the binding of human hepcidin to ferroportin, and is a potent inhibitor of hepcidin activity in a recombinant ferroportin expressing HEK 293 cell-based assay. In addition, this antibody was able to significantly inhibit hepcidin-induced increase in ferritin levels using Caco-2 cells, a human enterocyte cell line that naturally expresses ferroportin. LY2928057 does not block the efflux of iron from ferroportin, nor does this antibody cause the internalization of this transporter in vitro. Administration of LY2928057 results in a dose dependent increase in serum iron and hepcidin in normal cynomolgus monkeys. LY2928057 may provide therapeutic benefit for patients with hepcidin-related anemia by stabilizing ferroportin located on the cell surface, thus restoring iron export and erythropoiesis. LY2928057 is currently in clinical evaluation.

Disclosures:
Witcher: Eli Lilly and Company: Employment, Equity Ownership. Leung:Eli Lilly and Company: Employment, Equity Ownership. Hill:Eli Lilly and Company: Employment, Equity Ownership. De Rosa:Eli Lilly and Company: Employment, Equity Ownership. Xu:Eli Lilly and Company: Employment, Equity Ownership. Manetta:Eli Lilly and Company: Employment, Equity Ownership. Wroblewski:Eli Lilly and Company: Employment, Equity Ownership. Benschop:Eli Lilly and Company: Employment, Equity Ownership.
Establishment Of a Reference Range For The Pbac-Score
Authors: Halimeh Susan , Rott Hannelore , Kappert Guenther , Siebert Manuela 
Published: October 2019

Introduction
Heavy menstrual bleeding (HMB) is defined as bleeding that lasts for more than seven days or as the loss of more than 80mL of blood per mentrual cycle (1)The menstrual blood loss can be quantified by the use of a pictorial bleeding assessment chart (PBAC).
The PBAC-Score was initially validated by Higham et al. (2) With the PBAC-Score the women can capture the number of pads or tampons and also state the intensity through the assessment of the drenching.
The aim of this study was to establish a reference range for the PBAC-Score.

Samples and Methods
We analysed samples of 310 women with menorrhagia and 108 controls by conducting the following tests: Blood count, VWF:RCo, VWF:Ag, VWF:CB, VWF:multimers, Fibrinogen (Clauss), activities of FII, FV, FVII, FVIII (clotting and chromogenic), FIX, FX, FXI, FXII, FXIII. In all women the menstrual blood loss was quantified usind the PBAC-Score and the results were compared.

Results
In 202 of 310 women (65.1%) a bleeding disorder could be detected. In those with a bleeding disorder, the distribution was as followed: 64% of these women had a von Willebrand disease, 7.2% FVII-deficiency, 7.7% FXIII-deficiency and the remaining 21.1% other mild factor dificiencies. The mean PBAC-Score in women with menorrhagia was 262 (range 31 – 4212) in our control group the mean PBAC-Score was 60 (range 8 – 97).

Discussion/Conclusion
Attemps to measure the quantity of menstrual blood loss can be useful in clinical practice.
In our opinion the best cut of for the PBAC-Score is 100 with a sensitifity of 90% and a specifity of 100%.
We found a high correlation of a PBAC >100 and an inherited bleeding disorder, especially von Willebrand diesease. In 65.1% of our patients an abnormal coagulation was found. In 4 (3.7%) women of the control group slightly abnormal von Willebrand parameters could been dectected.
We validated the reference range for the PBAC-Score as 0 - 100.

Disclosures:
Halimeh: Octapharma AG: Investigator Other, Research Funding.
Factor XIII Deficiency As Underlying Cause Of Unexplained Bleeding
Authors: Mercado Marta Ruiz , Cozzarelli Silvia Verdesoto , Calderón-Cabrera Cristina , Vázquez Ramiro Núñez , Bárcenas Reyes Jiménez , Garrido Rosario Pérez , Pérez-Simón Jose Antonio , Rodríguez Martorell Francisco Javier 
Published: October 2019

Introduction
Factor XIII deficiency (FXIII) is an uncommon coagulation disorder. Congenital FXIII deficiency, generally due to mutations in F13A1 gene, presents with early life- threating hemorrhages in homozygotes. Acquired deficiency, a more rare state, has been associated with certain drugs and inhibitors against FXIII.

Materials and methods
We retrospectively analyzed 47 patients (male:female 1:1.3). Study criteria were unexplained hemorrhage, mainly after surgery, or spontaneous intracranial bleeding at perinatal period and no relevant findings in conventional haemostasia assays, from 01/01/2010 to 15/07/2013. FXIII measure was performed by a functional method.

Results
20 out of 47 patients (42.5%) other abnormalities that might contribute to bleeding were detected: 13 had primary haemostasis disorders and 7 had low levels of a coagulation factor different from FXIII. In 10 patients, FXIII deficiency was observed: 4 congenital and 6 acquired. In all acquired deficiencies, the presence of an inhibitor was discarded. Patients with congenital FXIII deficiency, had mucocutaneous bleeding in 75% of cases and hemorrhage after surgery in 50%. However, there was no intracranial hemorrhage. In acquired deficiency (median FXIII 44.5 U/dl at first diagnostic work up), mucocutaneous bleeding appeared in 40% patients and postoperative and intracranial hemorrhage in 100%. In 8/ 10 patients FXIII concentrate was administered, achieving bleeding control in 7. In 3 cases of congenital deficiency, prophylactic substitutive therapy was started enabling a cessation of new bleeding episodes, except for a posttraumatic muscle hematoma; median FXIII levels reached 6.8 U/ dL. 2 patients with acquired deficiency died of non-hemorrhagic complications, 3 patients developed spontaneous remission of the deficiency in a median time of 2 months and 1 is still receiving substitutive therapy.

Conclusions
In congenital deficiency, maintenance of FXIII through levels in the range of 5-10% is enough to avoid bleeding manifestations. The acquired deficiencies have at least the same frequency as congenital, develop hemorrhage episodes at higher levels of factor and respond to therapy in a thrifty way. For those reasons, tests for FXIII are essential for diagnosis in high index clinical suspicious cases, such as unexplained bleeding.

Disclosures:
No relevant conflicts of interest to declare.
Molecular Analysis Of The Largest Group Of Patients With Factor XIII Deficiency In Southeast Of Iran
Authors: Naderi Majid , Dorgalaleh Akbar , Alizadeh Shaban , Tabibian Shadi , Bamedi Taregh , Karimi Mehran 
Published: October 2019

Background
Factor XIII deficiency is an extremely rare hemorrhagic disorder with estimated incidence of 1/3000000 million. Sistan and Baluchistan, southeast of Iran has the highest prevalence of disease worldwide. Thus the aim of this study was to assess molecular characteristics of this large group of patients with factor XIII deficiency.

Methods
This descriptive study was conducted on one hundred and nineteen patients from same number of unrelated families. Genotype analysis for factor XIII subunit A Val34Leu, Tyr204Phe, and Pro564Leu and Trp187Arg was performed for all patients.

Results
Molecular analysis of this large group of patients with severe factor XIII deficiency revealed that all studied patients were homozygous for TGG CGG mutation at codon 187, in exon 4 of FXIII-A1 gene. Val34Leu, Tyr204Phe, and Pro564Leu FXIII-A subunit gene polymorphisms were not observed in any of patients.
In the study population, umbilical cord bleeding, deep soft tissue and hematoma were the most common clinical manifestations and was observed in 82.5%, 53% and 31% respectively.

Conclusion
Trp187Arg is the most common mutation of FXIII-A subunit in southeast of Iran and probably due to the large number of patients in this area (352 patients), is the most common mutation of factor XIII worldwide.

Disclosures:
No relevant conflicts of interest to declare.
Engagement of interleukin-7 receptor stimulates tyrosine phosphorylation, phosphoinositide turnover, and clonal proliferation of human T-lineage acute lymphoblastic leukemia cells
Authors: Dibirdik I , Langlie MC , Ledbetter JA , Tuel-Ahlgren L , Obuz V , Waddick KG , Gajl-Peczalska K , Schieven GL , Uckun FM 
Published: October 2019

Abstract
The purposes of this study were to examine the biologic effects of the engagement of the interleukin-7 receptor (IL-7R) with recombinant human interleukin-7 (rhIL-7) in immunophenotypically distinct T-lineage acute lymphoblastic leukemia (ALL) blasts and to elucidate the biochemical nature of the IL-7R-linked transmembrane signal in rhIL-7-responsive T- lineage ALL blast populations. In the absence of costimulants, rhIL-7 stimulated the in vitro proliferation and colony formation of freshly isolated leukemic blasts from six to eight T-lineage ALL patients with a mean plating efficiency of 196 +/- 53 (background subtracted) colonies/10(5) blasts plated. Stimulation of T-lineage ALL blasts with rhIL-7 resulted in markedly enhanced tyrosine phosphorylation of six distinct phosphoproteins with molecular weights of 57, 72, 98, 123, 150, and 190 Kd, and induced a rapid increase in the production of inositol-1,4,5-trisphosphate (Ins-1,4,5-P3), which was inhibitable by the tyrosine-specific protein kinase inhibitor genistein, but not by the serine/threonine-specific protein kinase C inhibitor H7. Similarly, rhIL-7 stimulated Ins-1,4,5-P3 production in CEM-1.3 T-lineage ALL cells and this stimulation was inhibitable by the tyrosine-specific protein kinase inhibitors genistein and herbimycin A, but not by H-7. Thus, the transmembrane signal triggered by engagement of the IL-7R is intimately linked to a functional tyrosine-specific protein kinase pathway and stimulates the phosphoinositide (PI) turnover and proliferation of T-lineage ALL blasts. The presented data confirm and extend previous studies on the expression of functional IL-7R on T- lineage ALL blasts and support the hypothesis that IL-7 may play an important regulatory role in the biology of T-lineage ALL.
Autoantibody activity of immunoglobulins isolated from B-cell follicular lymphomas
Authors: Dighiero G , Hart S , Lim A , Borche L , Levy R , Miller RA 
Published: October 2019

Abstract
Previous work with monoclonal Igs (MIgs) has demonstrated that a high proportion of paraproteins bind to self-antigens such as the Fc fragment of IgG, Ii blood group antigens, cytoskeleton proteins, DNA, and myelin-associated glycoprotein (MAG). Recent work in CLL indicates that CD5+ B lymphocytes are frequently committed to production of autoantibodies. We have examined the antibody specificity of MIgs derived from the tumor cells of 31 different patients with CD5- B-cell lymphomas. Our results indicate that the tumor cells from 8 of these 31 patients (25.8%) express Igs with autoantibody activity. In two cases antibody activity was multispecific. In four cases, antibody activity was exclusively directed against the Fc fragment of IgG, whereas the two other cases bound to both Fc fragment of IgG and nuclear antigens. Most non-Hodgkin's lymphomas (NHL) are derived from CD5- B cells. These results indicate that like CLL, NHL also express Igs that frequently have autoantibody activity.