bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Phase I/II Trial Evaluating The Use Of a Histone Deacetylase Inhibitor Panobinostat (LBH589) In Addition To Glucocorticoids In Patients With Acute Graft-Versus-Host Disease
Authors: Perez Lia , Fernandez Hugo F , Tomblyn Marcie , Locke Frederick L , Field Teresa , Pidala Joseph , Elmer Erika , Beato Francisca , Villagra Alejandro , Anasetti Claudio 
Published: October 2019

Abstract
Graft-versus-host disease (GVHD) remains the principal obstacle to achieve successful outcomes in allogeneic hematopoietic stem cell transplant (HCT). Glucocorticoids are the current standard initial treatment for acute GVHD with complete responses of 25% to 41%. New immunosuppressive strategies are required to improve management of acute GVHD and decrease toxicities of immunosuppressive agents. We conclude that more effective acute GVHD therapy might improve remission rates that will result in better survival after allogeneic HCT. Vorinostast, a histone deacetylase inhibitor (HDACi) have shown efficacy for acute GVHD prevention. This protocol was design to test the safety and potential efficacy of a novel HDACi, panobinostat (LBH589), administered to patients with acute GVHD within 72 hours of initiation of glucocorticoid therapy (methylprednisolone 0.8 mg/Kg/day IV or equivalent for at least 14 days) as first line therapy. Panobinostat is a potent inhibitor of deacetylases and HSP90 belonging to a structurally novel class of the cinnamic hydroxamic acid class of compounds and is one of most potent HDAC inhibitors. We have enrolled n=13 subjects, median age 52 (range, 39-63) years, male n=8/female n=5, median day of GVHD development day + 37 post HCT (26 -528 days) with overall grade GVHD II (n=8) or III (n=5). The first three patients were treated with 2.5MG/M2 intravenously (IV) weekly x 4 and subsequent subject was treated with 5MG/M2 IV weekly x 4 achieving all GVHD CR by day +15. Patients were treated with azole for fungal prophylaxis. Due to manufacturer discontinuation of IV formulation production we were obliged to amend the protocol to use PO Panobinostat. Using 10MG PO TIW 3 doses q week x 4 weeks, we treated 2 subjects which were both discontinued from study drug as evidence of GHVD progression within 7 days of Panobinostat. Due to safety concerns, the next group was treated with a reduce dose of 5 MG PO TIW q week x 4 (Level -1). So far we have accrued 7 subjects whom by day 15 achieved GVHD CR (n:4) and PR (n:3) majority being in CR (n:6/7) on day +28 and PR (n:1). Toxicities by CTCAE 4.0 criteria included reversible thrombocytopenia and neutropenia grade 1-2 possible related to study drug. We are encouraged with a GVHD CR rate of 57% on day +15 and 86% CR at study drug completion on day+36. These results suggest a role HDACi Panobinostat as a tool to improve success of glucocorticoids for GVHD treatment. Correlative studies are planned to address pharmacodynamics of Panobinostat on inflammatory cytokines, to correlate DAC enzymatic activity inhibition and clinical response and to proteins/histones acetylation in T-cell subsets.

Disclosures:
No relevant conflicts of interest to declare.
Prospective Evaluation Of Allo-HSCT From Haploidentical-Related Donors Compared With Matched Sibling Donors and Unrelated Donors For Patients With Hematological Malignancies: Results From An Open-Label Trial
Authors: Luo Yi , Xiao Haowen , Lai Xiaoyu , Shi Jimin , Tan Yamin , He Jingsong , Xie Wanzhuo , Zheng Weiyan , Zhu Yuanyuan , Ye Xiujin , Cai Zhen , Lin Maofang , Huang He 
Published: October 2019

Abstract

Introduction
The order of alternative donor selection for hematopoietic stem cell transplantation (HSCT) for patients with hematologic malignancies has not been addressed. We performed the first prospective trial to compare the effect of HSCT from matched sibling donors (MSDs), unrelated donors (URDs) and haploidentical- related donors (HRDs) in a contemporary protocol.

Methods
From 2008 to 2012, 234 patients with hematologic malignancies were enrolled. The treatment schedule was as follows: if a fully MSD was available, patients were assigned treatment with MSD-HSCT. If an MSD was unavailable, a suitably matched URD was used as the alternative, where a suitable match involved matching more than 8 of 10 HLA-A, -B, -C, -DRB1and DQ allele loci ( ¡Ý 8/10) and at least 5 of 6 matching HLA-A, -B, and -DRB1 antigen loci. If only URDs with > 2 mismatching allele loci were available, patients were allowed treatment with HRD-HSCT.

Results
(1) Sixty-eight patients underwent MSD-HSCT, 98 patients underwent URD-HSCT, and 68 patients underwent HRD-HSCT (Table 1). (2) Grades II¨CIV and severe aGVHD were all significantly more frequent in patients undergoing HRD-HSCT compared with those undergoing MSD-HSCT (II¨CIV: 42.6% vs 19.1%, P = 0.0015; severe aGVHD: 17.65% vs 5.88%, P = 0.03). However, the incidences of II¨CIV and severe aGVHD were comparable in patients receiving transplants from HRDs to those from URDs (II¨CIV: 42.6% vs 40.8%, P = 0.89; severe aGVHD: 17.65% vs 13.27%, P = 0.48). The incidence of cGVHD was not significantly affected by donor types. (3) The 4-year incidence of relapse was not significantly affected by donor types according to all patients (24.2% in the MSD cohort, 22.8% in the URD cohort, 11.9% in the HRD cohort, P > 0.05). However, after controlling for high-risk patients, a superior graft-versus-leukemia (GVL) effect was observed in patients undergoing HRD-HSCT compared to MSD-HSCT or URD-HSCT. In high-risk patients receiving MSD, 36.8% experienced relapse, as did 33.6% in the URD cohort, but the incidence decreased to11.1% in the HRD cohort (MSD vs HRD, P = 0.015; URD vs HRD, P = 0 .028). (4) HRD-HSCT yielded comparable rates of 4-year overall survival (OS) and disease-free survival (DFS) to MSD-HSCT ( OS: 66.4% vs 79.5%, P = 0.071; DFS: 66.4% vs 78.2 %, P = 0.109) or URD-HSCT (OS: 66.4% vs 59%, P = 0.952; DFS: 66.4% vs 58.1%, P = 0.864) (Figure 1).

Conclusion
Our data provide convincing clinical evidence to support the use of HRDs, as well as URDs, can be selected as first-line alternative donors, especially for high-risk patients.

Disclosures:
No relevant conflicts of interest to declare.
Regulatory Role Of Mitochondrial Aconitase and Isocitrate In Iron-Responsive, Erythropoietin Receptor Signaling During Anemia
Authors: Bullock Grant C , Schrott Valerie 
Published: October 2019

Abstract
Several clinical observations illustrate the link between iron and erythropoietin (Epo)-mediated signaling in early erythroid progenitor cells. In iron deficiency anemia (IDA) erythropoiesis is blocked at an early stage despite increased serum Epo concentrations. Intravenous iron improves the effectiveness of exogenous Epo in patients with Epo-refractory anemia of chronic disease. These clinical observations suggest that iron dominantly regulates Epo-receptor (EpoR) signaling. However, the mechanism of this iron-mediated signaling remains unclear. We recently demonstrated that 1) the aconitases, multifunctional iron-sulfur cluster proteins that convert citrate into isocitrate are essential in the iron- Epo-signaling pathway in early erythroid progenitors, and that 2) isocitrate, the downstream product of aconitase, can enhance the effectiveness of Epo during iron deficiency in vitro and in vivo in mice with IDA and in rats with the anemia of chronic inflammation. These observations suggest that isocitrate or derivatives of isocitrate that synergize with erythropoiesis stimulating agents have important therapeutic application in the treatment of anemia. New data from my lab also shows that cellular iron restriction regulates mitochondrial oxygen consumption rates differentially over time during red blood cell differentiation, suggesting a novel link between mitochondrial function and erythropoeisis. We also see an increase in mitochondrial superoxide anion production in iron deprived erythroid progenitors. Based on these data, we hypothesize that mitochondrial aconitase is an iron sensor that integrates mitochondrial redox signaling to EpoR signaling and subsequent red blood cell production. To test this hypothesis we are investigating the iron dependent mechanisms by which aconitase, isocitrate, reactive oxygen species and mitochondrial metabolic pathways alter EpoR signaling. The clinical relevance of this project lies in its potential for the development of new iron-free agonists and antagonists of red blood cell production. Agonists may benefit patients with anemia due to iron deficiency or chronic inflammation and antagonists may benefit patients with myeloproliferative neoplasms.

Disclosures:
No relevant conflicts of interest to declare.
Initial Change Of Iron Metabolic Flux Prior To Differentiation Of Erythroid Progenitors After Epoetin Beta Pegol (C.E.R.A.) Treatment
Authors: Sasaki Yusuke , Noguchi-Sasaki Mariko , Matsuo Yukari , Fukumura Junko , Sato-Inomata Fumi , Yorozu Keigo , Shimonaka Yasushi 
Published: October 2019

Abstract

Introduction
Erythropoiesis and iron metabolism are inextricably linked. Developing immature erythroblasts have an extremely high iron requirement, especially during hemoglobin synthesis. Hepcidin, which inhibits iron efflux by binding to iron exporter ferroportin, is suppressed to promote the supply of required iron. Suppression of hepcidin after erythropoiesis-stimulating agent (ESA) treatment is mainly in an indirect manner, especially via erythropoietic activity, but the nature of suppressive mechanism of hepcidin is still unknown. Epoetin beta pegol (C.E.R.A.) is a novel long-acting ESA, which potentially has intensive and continuous effects on reduction of hepcidin. In the present study, we investigated change of iron metabolic flux associated with enhanced erythropoiesis by C.E.R.A. to analyze the mechanism underlying suppression of hepcidin.

Methods
Initial change of iron metabolism was analyzed in C57BL/6N mice intravenously treated with 10 μg/kg of C.E.R.A. or vehicle. Hematological indices such as reticulocyte counts and iron indices including serum hepcidin and iron levels were measured. Reticulocyte hemoglobin equivalent (Ret-He) which reflects the iron status of reticulocyte was also determined. Ter119 and transferrin receptor (CD71) expression on bone marrow cells was evaluated by flow cytometry for analysis of the maturation status of bone marrow erythroblasts.

Results
C.E.R.A. suppressed serum hepcidin levels after 9 hours, while serum iron levels were significantly decreased at 9 hours followed by recovery to the control levels at 24 hours. Ter119(+)CD71(high) immature erythroblasts were decreased and CD71 expression levels on the same cells were increased at 9 hours after C.E.R.A. treatment. C.E.R.A. elevated reticulocyte counts and Ret-He levels at 48 hours.

Discussion and Conclusion
Transient decrease in serum iron levels and continuous suppression of serum hepcidin levels were observed in early phase after C.E.R.A. treatment, prior to increase in erythroblasts through proliferation and differentiation of erythroid progenitors. Furthermore, considering decrease in immature erythroblasts followed by increase in hemoglobin-rich reticulocytes, it is possible that initial change of iron metabolic flux occurred by the accelerated iron incorporation into immature erythroblasts through CD71 recycling after C.E.R.A. treatment. These results suggest that sensing initial change of iron metabolic flux leads to suppression of hepcidin after C.E.R.A. treatment, but further analysis is needed for the mechanism of increase in iron absorption into immature erythroblasts immediately after C.E.R.A. treatment independent of differentiation of erythroid progenitors.

Disclosures:
No relevant conflicts of interest to declare.
Early Detection Of Right Ventricular Diastolic Dysfunction By Pulsed Tissue Doppler Echocardiography In Iron Loaded Beta Thalassemia Patients
Authors: El-Beshlawy Amal , Agha Hala , Hamdy Mona Mohamed , Sobeih Alaa , Alzahraah Fatma , Abdelsattar Inas , Abdelmassih Antoine , Said Fadwa , Abdelaziz Osama , Eltagui Mona , Dudley Pennell 
Published: October 2019

Abstract

Introduction
Iron overload contributes to cardiac dysfunction in patients with beta thalassemia. Early heart iron overload can be quantified through cardiovascular magnetic resonance (CMR) T2*.

Objective
to clarify the value of tissue Doppler imaging (TDI) in early detection of global myocardial dysfunction in iron loaded thalassemia major patients diagnosed by CMR.

Patients and Methods
Two groups were included in the study; Group I: 69 asymptomatic thalassemia patients (28 females, 41 males), mean age 18.1±7.03 years (range 6 to 39 years), Group II (n=41) healthy normal controls matched for age and sex. Serum ferritin and CMR were performed to assess the degree of cardiac siderosis (T2*< 20 ms). Group I was subdivided into two subgroups; Group Ia (n=26) T2*<20ms and Group Ib (n=43) T2* >20ms. Conventional echocardiography and Doppler of LV, RV dimensions and functions and pulmonary artery pressure were evaluated. TDI measures included systolic and diastolic myocardial velocities (S', E', A' and E'/A') of the basal segments of septal, lateral LV and RV free walls.

Results
Right ventricular diastolic function assessed by tricuspid annular E'/A' was positively correlated with T2* value; the lower tricuspid E'/A' ratio the lower T2* value (r = +0.366, P=0.002). Tricuspid annular A' was significantly higher in group Ia compared to group Ib (16.7 ±5.2cm/s versus 12.1 ±4.0cm/s, P<0.001). Tricuspid E'/A'<1 was common in group Ia compared to group Ib (19/26 (73.0%) versus 3/43 (6.97%), P=0.000). Group Ia (T2*<20ms) had high serum ferritin level compared to group Ib (T2*>20ms) (6,357±2478 microgram/L versus 2,965±2289 microgram/L (P<0.0001). By multivariate logistic regression analysis, right ventricular diastolic dysfunction (tricuspid E'/A'< 1) was associated with serum ferritin and T2* level of the thalassemic patient.

Conclusion
Pulsed tissue Doppler imaging (TDI) is a promising tool for quantitative assessment of myocardial function and early detection of right ventricular diastolic dysfunction in iron loaded beta thalassemia major patients assessed by cardiovascular magnetic resonance.

Disclosures:
No relevant conflicts of interest to declare.
Features Associated With Pulmonary Hypertension In Splenectomized Patients With Hemoglobin E/β-Thalassemia Disease
Authors: Chuncharunee Suporn , Atichartakarn Vichai , Udomsubpayakul Umaporn , Archararit Napaporn 
Published: October 2019

Abstract

Introduction
Pulmonary hypertension (PHT) associated with thalassemia hemoglobinopathy is now an accepted clinical entity. Due to a high prevalence of thalassemia hemoglobinpathy worldwide, it is the most common entity of PHT. Despite the commonness, its pathogenesis is not yet completely understood. Although asplenia is a known risk factor, PHT does not develop in all splenectomized patients. The present study was therefore done to search for other associated features.

Patients and Methods
Sixty-one clinically stable splenectomized hemoglobin E/β-thalassemia disease (E/β-Thal) adult outpatients, on no medication aside from folic acid and who received no blood transfusion in the preceding 4 weeks, were prospectively studied. All gave written informed consent, and study protocol was approved by the institution ethics committee on studies in humans (#0774/2548). Transthoracic echocardiogram was used to evaluate cardiac function and to estimate pulmonary artery systolic pressure (PASP). PHT was defined as an estimated PASP ≥36 mmHg. Clinical features and laboratory data were dichotomized according to the presence (PHT+) or absence (PHT-) of PHT, and statistical analysis was done by STATA version 10 (Stata Corp, Texas), considering a P value<0.05 as statistically significant.

Results
Of the 61 patients, 32 (52.5%) were PHT+, 14 of whom were female. There was no gender difference between the 2 groups (p=0.246). All had normal left ventricular ejection fraction, and none had positive serology for human immunodeficiency virus. Results expressed in mean ± SD or median (range) of the various measured parameters and their statistically significant differences are shown in the following table.

Conclusions
PHT was found in 52.5% of the 61 splenectomized E/β-Thal patients with no gender preponderance. Although PHT was found mostly after the first decade of splenectomy, its prevalence did not correlate with time elapsed since the procedure. Features associated with PHT in splenectomized E/β-Thal patients were greater transfusion requirement, lower RBC counts, higher serum lactate dehydrogenase (LDH) and lower serum cholesterol levels, as a reflection of more severe disease and more severe ineffective erythropoiesis; together with a higher serum soluble vascular cell adhesion molecule-1 (VCAM-1) levels, likely from chronic hypoxemia.

Disclosures:
No relevant conflicts of interest to declare.
Binding Of Immune Serine Proteases To Nucleic Acids Enhances Their Nuclear Localization and Promotes Their Cleavage Of Nucleic Acid-Binding Protein Substrates
Authors: Whangbo Jennifer , Thomas Marshall , McCrossan Geoffrey , Deutsch Aaron , Martinod Kimberly , Walch Michael , Lieberman Judy 
Published: October 2019

Abstract
When released from cytotoxic T lymphocytes and natural killer cells, Granzyme (Gzm) serine proteases induce programmed cell death of pathogen-infected cells and tumor cells. The Gzms rapidly accumulate in the target cell nucleus by an unknown mechanism. Many of the known substrates of GzmA and GzmB, the most abundant killer cell proteases, bind to DNA or RNA. Gzm substrates predicted by unbiased proteomics studies are also highly enriched for nucleic acid binding proteins. Here we show by fluorescence polarization assays that Gzms bind DNA and RNA with nanomolar affinity. We hypothesized that Gzm binding to nucleic acids enhances nuclear accumulation in target cells and facilitates their cleavage of nucleic acid-binding substrates. In fact, RNase treatment of cell lysates reduced cleavage of RNA binding protein (RBP) targets by GzmA and GzmB. Moreover, adding RNA to recombinant RBP substrates greatly enhanced in vitro cleavage by GzmB, but adding RNA to non-nucleic acid binding proteins did not. For example, exogenous RNA enhanced GzmB cleavage of recombinant hnRNP C1 (an RBP) but not LMNB1 (a non-RBP). In addition, GzmB cleaved the RNA-binding HuR protein efficiently only when it was bound to an HuR-binding RNA oligonucleotide, but not in the presence of an equal amount of non-binding RNA. Thus, nucleic acids facilitate Gzm cleavage of nucleic acid binding substrates.
To evaluate whether nucleic acid binding influences Gzm trafficking in target cells, we incubated fixed target cells with RNase and then added Gzms. RNA degradation in target cells reduced Gzm cytosolic localization and increased nuclear accumulation. Similarly, pre-incubating Gzms with exogenous competitor DNA reduced Gzm nuclear localization. The Gzms form a monophyletic clade with other immune serine proteases including neutrophil elastase (NE) and cathepsin G (CATG). Upon neutrophil activation, NE translocates to the nucleus to drive the formation of neutrophil extracellular traps (NETs). NE and CATG, but not non-immune serine proteases such as trypsin and pancreatic elastase, also bind DNA with high affinity and localize to the nucleus of permeabilized cells. Consistent with this finding, competitor DNA also blocks the nuclear localization of NE. Moreover NE and CATG localization to NETs depends on DNA binding. Thus the antimicrobial activity of NETs may depend in part upon the affinity of these proteases for DNA. Our findings indicate that high affinity nucleic acid binding is a conserved and functionally important property of serine proteases involved in cell-mediated immunity.

Disclosures:
Lieberman: Alnylam Pharmaceuticals: Membership on an entity’s Board of Directors or advisory committees.
CD8+ Treg - From Mouse To Man
Authors: Holderried Tobias A.W. , Kim Hye-Jung , Lang Philipp A , Cantor Harvey 
Published: October 2019

Abstract
T cell-mediated regulation of the immune response to self and foreign antigens is essential to maintain immune homeostasis and prevent autoimmune tissue destruction. The majority of studies addressing this issue, both in mice and humans, have focused on the contribution of CD4+CD25+FOXP3+ regulatory T cells. The contribution of regulatory CD8+ T cells has not been appreciated until recently. Recent studies have identified a small subset of IL-15 dependent CD8+ regulatory T cells (Treg) that is essential for maintenance of self- tolerance and prevention of autoimmune disease in mice. Expression of a triad of cell surface markers – CD44+CD122+Ly49+ – has been used to distinguish and purify CD8+Treg (Kim et al., Nature 2010; Kim et al., PNAS 2011).
Here we have defined the human homologue of CD8+ Treg. The Ly49 receptor, identified as a stable surface marker on CD8+ Treg, is a member of a multigenic/multiallelic receptor family recognizing classical MHC class I molecules. The functional homologue of murine Ly49 is the killer cell immunoglobulin-like receptor (KIR). Our analysis has revealed that, while expression of KIR subtype combinations appears to be stochastic and co-expression of these KIR receptors is random, the inhibitory KIR2DL2/3 and KIR3DL1 subtypes are dominantly expressed by human CD3+CD8+ T cells. Similar to murine CD8+ Treg, CD8+ T cells that express KIR2DL2/3 or KIR3DL1 also express CD44 and CD122. Moreover, consistent with murine CD8+ Treg, incubation with IL-15 results in activation and proliferation of KIR+CD8+ T cells that maintain a stable surface phenotype. Gene array analyses in mice has indicated that Helios, a highly conserved zinc finger transcription factor and member of the Ikaros family of transcription factors, is expressed by CD44+CD122+Ly49+ CD8+ Treg. Helios is involved in T cell development and expressed by ∼70% of FoxP3+CD4+ Treg but not by mature B cells, dendritic cells or myeloid cells. Our analyses identified a Helios+ subset in the CD8+ Treg population, which (compared to the Helios- subset) embodies many of the functional characteristics of CD8+ Treg in mice. Co-expression of Helios is also apparent in some KIR+CD8+ T cells in human samples. In mice, we have shown that CD8+ Treg target CD4 TFH cells and thus maintain self-tolerance. In vitro suppression assays revealed that KIR+CD8+ cells but not KIR–CD8+ cells confer inhibitory activity on CD4+CXCR5+ TFHtarget cells in humans.
Taken together, our findings implicate KIR+CD8+ cells as the human homologue of murine CD8+ Treg, including expression of transcription factor Helios, responsiveness to IL-15 and suppression of CD4+ TFH cells. Understanding the genetic and biological features of this CD8+ T cell subset in humans opens the possibility of exploiting their regulatory activity for the development of immunotherapy in the context of autoimmune disease and cancer.

Disclosures:
No relevant conflicts of interest to declare.