bluuebunny/crossref_metadata_2025_split huggingface dataset:
Autologous (Auto) Peripheral Blood Stem Cell (SCT) As a Consolidation Therapy for Patients with Acute Myeloid Leukemia (AML) in 1st Complete Remission (CR): A Single Institution Experience
Authors: Buttar Amanpreet , Jagadeesh Deepa , Cerny Jan , Ramanathan Muthalagu , Zhou Zheng , Petrillo-Deluca Laura , Tarrasky Natasha , Bednarik Jayde , Desai Zankar , Walsh William V , Nath Rajneesh 
Published: October 2019

Abstract
Abstract 4505

Introduction:
Patients with AML in 1st CR are frequently consolidated with an auto SCT but the role of this modality in the management of AML is still not fully defined.

Methods:
Retrospective analysis was performed on all patients who underwent an auto SCT for AML in 1st CR at UMass Memorial Medical Center from January 2000 to December 2010. Data was analyzed as of August 2011. The study was approved by UMass Memorial Medical Center IRB.

Results:
25 Patients were identified from the database. There were 13 males and 12 females. The median age was 46 years range (19–72). Cytogenetics was good risk in 6 patients, intermediate risk in 14, poor risk in 3 and unknown in 2 patients. Induction chemotherapy was standard dose Ara-C based in 13 patients and high dose Ara-C based regimen in 12 patients. Median time from diagnosis to transplant was 133 days range (107–362). Stem cell mobilization regimen consisted of Ara-C/Etoposide (E) in 21 (80%), Cyclophosphamide (Cy) in 3 (12%) and Mitoxantrone/Ara-C/E in 1 (4%). Preparative regimen included Busulfan (Bu) 4/ E in 17 (68%), Bu4/Cy in 5 (20%) and high dose Melphalan in 3 (12%). A median of 4.56 ×106 range (1.05 × 106 – 9.67 × 106 ) CD34 cells/kg were infused. 3 patients failed to engraft. Median time to neutrophil recovery was 11 days range (9 to 16) and platelet recovery was 20 days range (9 to 116). 100 day mortality was 12% (3/25). Median follow of the entire cohort is 6.5 years range (0.6 – 10.7). Total of 9 patients died. The cause of death included disease in 7, sepsis in 1 and unknown in 1 patient. Kaplan Meier estimate for progression free survival (PFS) and overall survival (OS) was 72% and 80% at 6 months and 62% and 61% at 3 years.

Conclusion:
ASCT is an effective and safe intensive consolidation therapy for patients with AML in 1st CR.

Disclosures:
No relevant conflicts of interest to declare.
Granulocytes Infiltrate The Intestine In a Zebrafish Model Of Inflammatory Bowel Disease
Authors: Geiger Brenda , Zhen Aileen W. , Kokkotou Efi , Fraenkel Paula G. 
Published: October 2019

Abstract
Inflammatory bowel disease (IBD) is a condition in which lymphocytes and neutrophils infiltrate the intestine, stimulate the production of various inflammatory cytokines, and injure the intestinal mucosa. Because of the conserved aspects of hematopoiesis in the zebrafish, we hypothesized that a zebrafish model of IBD would reproduce human features of the disease, while retaining desirable aspects of zebrafish disease models including small size, low cost, and ease of chemical and genetic screening. We used adult transgenic zebrafish expressing eGFP under control of a myeloperoxidase promoter (Tg(mpx:eGFP) to trace the activity of granulocytes following intrarectal injection with trinitrobenzene sulfonic acid (TNBS), 1.6 mmole/gram body weight, or an equivalent volume of vehicle alone (30% ethanol). The zebrafish were sacrificed 6 hours’ post-treatment for assessment of changes in intestinal architecture, intestinal infiltration by myeloperoxidase-positive leukocytes, and cytokine transcript levels using histology, flow cytometry, and quantitative realtime RT-PCR, respectively. At 6 hours post-treatment, we detected a mononuclear infiltrate in the intestinal mucosa and a 10-fold increase in the number of myeloperoxidase-positive leukocytes in the intestines of TNBS-treated fish vs controls (0.614%±0.202% vs. 0.052%±0.014%, p=0.0269; n=6-7 fish per group). We also observed a significant increase in the transcript levels of interleukin-1beta (6,935±2,454 AU vs 100±28 AU, p=0.0179), interleukin-8 (246 ± 63 AU vs 100 ± 21 AU, p=0.05) and interleukin-10 (385 ± 84 AU vs 100± 8 AU p=0.0055) in the intestines of fish injected with TNBS vs vehicle alone (n=9-10 fish per group). These findings resemble those seen in patients and mammalian chemical injury models of IBD. They will provide the basis for further study of the mechanisms controlling intestinal inflammation in IBD.

Disclosures:
No relevant conflicts of interest to declare.
Interleukin-4 Regulates Eomesodermin In CD8+ T Cell Development and Differentiation
Authors: Carty Shannon A. , Jordan Martha S 
Published: October 2019

Abstract
Cytokines regulate T cell development and function. Interleukin (IL)-4 is a cytokine classically associated with CD4+ T helper (TH) differentiation, specifically TH2 differentiation. However, IL-4 has recently been shown to drive the development of CD8+ innate-like lymphocytes (ILLs). CD8+ ILLs are non-conventional thymocytes that develop with characteristics typically associated with innate and/or memory immune cells, including surface expression of the activation/memory markers CD44 and CD122, expression of the T-box transcription factor Eomesodermin (Eomes) and the rapid production of interferon (IFN)-γ after ex vivo stimulation. Here we show that IL-4 is sufficient to promote Eomes expression in CD8 single-positive (SP) thymocytes in short-term in vitro culture and direct CD8+ ILL development in fetal thymic organ culture. Using genetic deficiency and pharmacologic inhibitors, we demonstrate that IL-4 up-regulation of Eomes in CD8SP thymocytes requires STAT6 and Akt signaling pathways. Next, we investigated the possibility that in addition to directing the fate of developing thymocytes, IL-4 might impact the function of mature CD8+ cells undergoing activation. We found that that in naïve peripheral CD8+ T the combination of IL-4 and low dose T cell receptor (TCR) stimulation is a potent inducer of Eomes. Futhermore, when combined, these stimuli promote the persistence of CD8+ T cells in an adoptive transfer model. Understanding how IL-4 directs CD8+ T cell differentiation may provide a novel way to enhance CD8+ T cell function in adoptive T cell therapies.

Disclosures:
No relevant conflicts of interest to declare.
Structural Studies Of The Factor VIII C2 Domain In a Ternary Complex With Two Inhibitory Antibodies Reveals Classical and Non-Classical Epitopes
Authors: Walter Justin D , Werther Rachel A , Brison Caileen M , Healey John F. , Meeks Shannon L. , Lollar John (Pete) S. , Clint Spiegel P. 
Published: October 2019

Abstract
The factor VIII C2 domain is a highly immunogenic domain, whereby inhibitory antibodies develop following factor VIII replacement therapy for congenital hemophilia A patients. Inhibitory antibodies also arise spontaneously in cases of acquired hemophilia A. The structural basis for molecular recognition by two classes of anti-C2 inhibitory antibodies that bind to factor VIII simultaneously has been investigated by small angle X-ray scattering and X-ray crystallography. The C2 domain/3E6 FAB/G99 FAB stable ternary complex, both in solution and in its crystalline state, illustrates that each antibody epitope resides on opposing faces of the factor VIII C2 domain. The 3E6 epitope is a classical antibody that forms direct contacts to the C2 domain at two loops consisting of Glu2181-Ala2188 and Thr2202-Arg2215, which inhibits the binding of the C2 domain to von Willebrand Factor and phospholipid surfaces. The G99 is a non-classical antibody that prevents proteolytic activation of factor VIII, and its epitope centers on Lys2227 and also makes direct contacts with loops Gln2222-Trp2229, Leu2261-Ser2263, His2269-Val2282 and Arg2307-Gln2311. Each binding interface is highly electrostatic, with positive charges present on both C2 epitopes and complementary negative charges on each antibody. A new model of phospholipid membrane association is also presented, where the 3E6 epitope faces the negatively charged membrane surface and Arg2320 is poised at the center of the binding interface. Furthermore, a 1.7 Å X-ray crystal structure of the porcine factor VIII C2 domain has also been determined, which supports the presented model for phospholipid binding. These results illustrate the complex nature of the polyclonal immune response against the factor VIII C2 domain, and further define the epitopes for both classical and non-classical inhibitory antibodies.

Disclosures:
No relevant conflicts of interest to declare.
Species-Specific Functions For Long Noncoding RNAs During Erythropoeisis
Authors: Paralkar Vikram R , Mishra Tejaswini , Luan Jing , Yao Yu , Kossenkov Andrew , Konuthula Neeraja , An Xiuli , Narla Mohandas , Bodine David M. , Hardison Ross C , Weiss Mitchell J. 
Published: October 2019

Abstract
Mammalian genomes encode thousands of long noncoding (lnc) RNAs, although the extent to which lncRNAs regulate biological functions is not known. Indeed, most lncRNAs show low levels of conservation among mammals, which could suggest limited or species-restricted functions. We used RNA-seq to identify 683 and 1189 lncRNAs expressed during mouse and human erythropoiesis respectively, of which ∼25% are erythroid-specific. Primary cell chromatin immunoprecipitation (ChIP) studies indicate that most mouse erythroid lncRNAs arise from classical promoters, and their genomic loci are bound by the hematopoietic transcription factors GATA1 and SCL/TAL1. Using the G1E-ER4 cell line, which has an inducible form of GATA1, we found that lncRNAs whose genomic loci are bound by GATA1 in primary cells are upregulated on GATA1 induction in the cell line, similar to coding genes.
We compared RNA-Seq transcriptomes of erythroblasts from 8 different mice strains and showed that lncRNA expression is highly conserved within strains of the same species. A comparison of the human and mouse lncRNA transcriptomes showed that only 15% of mouse erythroblast lncRNAs have detectable syntenic transcripts in human erythroblasts, and that most lncRNAs are not detectable in humans.
To identify functional lncRNAs, we used RNA interference in primary erythroblasts to analyze the functions of 21 abundantly expressed murine erythroid lncRNAs, 15 of which are mouse specific and 6 of which have orthologous transcripts in humans. Suppression of seven different lncRNAs inhibited various aspects of erythroid maturation including loss of cell volume, down-regulation of the surface marker CD44, and enucleation. The suppression of enucleation ranged from 25% reduction to 75% reduction of enucleation demonstrated with at least 2 separate shRNAs for each of the 7 lncRNAs (p<0.0005) (Figure 1). Of the seven lncRNAs that have a demonstrable function in murine erythropoiesis, none are expressed in human erythroblasts, indicating that lack of conservation between different species does not necessarily predict a lack of function. These results reflect marked evolutionary differences between protein-coding genes and lncRNAs, and indicate that the latter exert tissue- and species-specific roles in mammalian development.Figure 1Figure 1.

Disclosures:
No relevant conflicts of interest to declare.
A Modified Dose Intensive R- CODOX-M/IVAC For HIV-Associated Burkitt and Atypical Burkitt Lymphoma(BL) Demonstrates High Cure Rates and Low Toxicity: Prospective Multicenter Phase II Trial Of The AIDS Malignancy Consortium (AMC 048)
Authors: Noy Ariela , Kaplan Lawrence , Lee Jeannette Y 
Published: October 2019

Abstract

Background
Concerns about the potential toxicity of the dose-intensive regimens typically used as treatment for BL in HIV seronegative patients prompted us to modify the CODOX-M/IVAC regimen with the goal of preserving efficacy while improving tolerability. The primary objective was to improve the 1 year overall survival (OS) from 65% based on historical reports to 85%. The early stopping rule for excessive treatment related mortality was not met.

Methods
Major modifications of the original US NCI regimen include the addition of rituximab, reduction in cyclophosphamide to 800 mg/m2 x 2 days, vincristine 2 mg cap, methotrexate 3000 mg/m2 on day 15, reduction of lumbar punctures using combination chemotherapy and continuous infusion of the IVAC portion for the high risk patients. Antibiotic prophylaxis and growth factor support were required. HAART therapy was continued at the discretion of the local investigator.

Results
Thirteen AMC centers entered 34 patients. Baseline characteristics included: Classical BL/unclassifiable between DLBCL and BL/other 71/21/9%; High Risk, 94% with stage III/IV 2 (6%)/25 (74%); Median age (range) 42 (19 – 55); CD4 count 195 (0 – 721), CD4 <100, 5 ( 27%); HIV viral load 1819 (Undetectable – 1,187,968). 12 patients had a viral load <100 and only 1 had undetectable plasma HIV RNA level. Only 14 patients were on HAART at study entry. Three/14 were on their second or greater antiretroviral regimen.
Treatment status
Patients with gr 3-5 treatment related toxicity: any 27; hematologic 20; infection 14 including febrile neutropenia 8; 6 metabolic including 1 tumor lysis syndrome; 4 neurologic; 2 thrombotic; and 1 each coagulation, GI or pain. Notably, only 2 patients had gr 1/2 stomatitis/mucositis and none had gr 3/4. Deaths: Seven patients died. There were three treatment-related deaths including encephalopathy with hepatic failure, hepatitis B and pneumonia (1); fungal infection (1) and complications of HIV (1). There were 2 deaths due to progressive lymphoma. Despite the 5 early treatment terminations, the 1 year overall survival was 83.1% (95% CI 63.9%, 92.6%) and the one year progression free survival was 74.1% (55.5%, 86.4%).

Conclusions
Modifications of the CODOX-M/IVAC regimen resulted in a gr 3/4 toxicity rate significantly lower than the 100% seen in the parent regimen, and no grade 3/4 mucositis was observed. Despite a protocol completion rate of only 68%, the 1-year survival rate was 83% which compares favorably with 2 reported studies that excluded HIV + pts. (Magrath et al, 1995; Mead et al, 2008) Correlative studies to improve our understanding of HIV-BL will be presented at the meeting.

Disclosures:
No relevant conflicts of interest to declare.
CD4+ Invariant Natural Killer T Cells Require NKG2D To Protect From Lethal Acute Graft-Versus-Host Disease
Authors: Schneidawind Dominik , Pierini Antonio , Alvarez Maite , Pan Yuqiong , Baker Jeanette , Meyer Everett , Negrin Robert 
Published: October 2019

Abstract
Invariant Natural Killer T (iNKT) cells are a rare cell population in humans (TCRα Vα24-Jα18) and mice (TCRα Vα14-Jα18) that are characterized by a rapid release of immunoregulatory cytokines upon stimulation. The tolerogenic impact of host iNKT cells on graft-versus-host disease (GVHD) after conditioning with total lymphoid irradiation and anti-thymocyte globulin (TLI/ATG) has been shown previously (Lan et al., BBMT 2003). Moreover, we recently described a subset of CD49b+ NKT cells overlapping with iNKT cells and providing protection from acute GVHD mainly via an IL-4-dependent mechanism (Leveson-Gower et al., Blood 2011). Here, we investigated the role of highly purified adoptively transferred donor-derived CD4+ iNKT cells. Balb/c recipient mice were transplanted with T cell-depleted bone marrow together with 1x106 CD4/CD8 T lymphocytes (Tcon) from C57Bl/6 donor mice after irradiation with 8 Gy. Mice co-injected with as low as 5x104 freshly isolated and highly purified (>99%) CD4+ iNKT cells showed a significant survival benefit compared to mice receiving Tcon alone (p=.0015). Consistently, weight and GVHD score improved in mice that received CD4+ iNKT cells. Signal intensity derived from expanding luciferase expressing alloreactive Tcon was significantly lower in animals treated with CD4+ iNKT cells demonstrating inhibition of proliferation of alloreactive Tcon through CD4+ iNKT cells (p<.0001). In vivo CFSE proliferation assay confirmed decreased Tcon proliferation in peripheral lymph nodes (p<.0001), mesenteric lymph nodes (p=.0277) and spleen (p=.0005). CD4+ iNKT cells showed a Th2-biased cytokine profile with high levels of IL-4 and IL-13 in the presence of alloreactive Tcon challenged with irradiated allogeneic stimulators. Co-injection of CD4+ iNKT cells that were expanded 5-fold in vitro with α-GalCer and IL-2 had the same protective effect from lethal acute GVHD compared to freshly isolated CD4+ iNKT cells (p=.7987). Interestingly, CD4+ iNKT cells derived from NKG2D-/- animals were significantly less effective in preventing acute GVHD lethality (WT vs. NKG2D-/-p=.0027). In conclusion, low numbers of highly purified freshly isolated and cultured CD4+ iNKT cells protect from lethal acute GVHD in mice and require NKG2D. Despite the fact that iNKT cells are a rare cell population, the feasibility of in vitro expansion with retained functionality of CD4+ iNKT cells provide the basis for clinical translation.
EM and RN contributed equally.

Disclosures:
No relevant conflicts of interest to declare.
Chimerism and Tolerance Without Gvhd In Mismatched Recipients Of Combined Hematopoietic Stem Cell/Kidney Transplants: Donor-Specific Hyporeactivity Is Not a Reliable Biomarker For Tolerance
Authors: Leventhal Joseph , Abecassis Michael , Miller Joshua , Gallon Lorenzo , Tollerud David J. , Elliott Mary Jane , Ildstad Suzanne T. 
Published: October 2019

Abstract
We recently reported that low-intensity conditioning combined with facilitating cell (FC)-enriched hematopoietic stem cell transplantation (FCRx) can safely achieve high levels of durable chimerism in unrelated and related mismatched kidney transplant (KTx) recipients. This is associated with stable renal function, complete absence of GHVD, and successful withdrawal of immunosuppression (IS). We herein present interim follow-up of now 19 subjects and present data to demonstrate that donor specific hypoactivity does not correlate with tolerance to the renal allograft if chimerism is not present.
HLA-mismatched related (n = 12) and unrelated (n = 8) living donor KTx recipients were conditioned with fludarabine (days -5,-4,-3), cyclophosphamide (50 mg/kg day -3, +3), 200 cGy TBI, (day -1), KTx (day 0), followed by infusion of cryopreserved G-CSF mobilized FCRx (day +1). Multilineage chimerism was assessed prospectively by STR analysis. Mixed lymphocyte reaction (MLR) and cell mediated lympholysis (CML) assays were performed to assess donor-specific hyporeactivity.
Subjects ranged in age from 18-65 years. 18 of 19 patients demonstrated peripheral blood macrochimerism at 1 month post-transplant (6% - 100%). The one patient who failed to engraft was highly sensitized (Class I PRA > 40%). No subjects developed acute or chronic GVHD or “engraftment syndrome.” Chimerism was transient in 4 subjects, each of which received either a suboptimal cell dose or had PRA > 20%. Durable whole blood and T cell chimerism was achieved in 14 subjects. All patients demonstrated in vitro donor-specific hyporesponsiveness (DSH) by MLR +/- CML post-transplant regardless of chimerism status. However, DSH in patients who lost chimerism was not predictive of successful IS weaning, as 3 of 4 transiently chimeric patients with DSH had subclinical Banff 1A rejection on protocol biopsy and while on tacrolimus monotherapy. Recurrence of underlying autoimmune disease has only occurred in subjects who were transiently chimeric. Protocol biopsies in chimeric subjects have exhibited normal histology for up to 3 years. Nine chimeric subjects are completely off IS from 1-34 months. The remainder are in the process of weaning.
The presence of durable, high level whole blood and T cell chimerism in combined kidney + FCRx recipients is a robust biomarker of tolerance. DSH alone without donor chimerism in the first post-transplant year does not predict successful IS withdrawal or tolerance.

Disclosures:
Tollerud: Regenerex, LLC: Equity Ownership. Ildstad:Regenerex, LLC: Equity Ownership.
A Randomized Phase II Study of Tosedostat in Combination with Either Cytarabine or Decitabine in Newly Diagnosed Older Patients with Acute Myeloid Leukemia or High-Risk Myelodysplastic Syndrome
Authors: Mawad Raya , Becker Pamela S. , Hendrie Paul C. , Scott Bart L , Wood Brent L. , Dean Carol , Sandhu Vicky , Deeg H. Joachim , Walter Roland B. , Wang Lixia , Singer Jack , Estey Elihu H. , Pagel John 
Published: October 2019

Abstract
Background: Tosedostat is an oral aminopeptidase inhibitor that has anti-neoplastic activity in a variety of malignancies. Pre-clinical assays have demonstrated synergy between tosedostat and both cytarabine and hypomethylating agents. We performed a randomized, open-label Phase II trial to determine the rates of complete remission (CR) and 4 month overall survival using tosedostat in combination with intermediate-dose cytarabine or decitabine in patients with untreated AML or high-risk MDS.
Methods: Patients ≥60 years old were randomized in a 1:1 fashion to receive tosedostat 120 mg daily by mouth days 1-21 with either 5 days of intravenous cytarabine 1 g/m2/day or decitabine 20 mg/m2/day delivered every 35 days for up to three cycles. Eight patients received 180 mg tosedostat daily continuously. Patients who obtained a CR or CR with incomplete blood count recovery (CRi) after 3 cycles of therapy were eligible to receive up to 2 additional cycles (maximum of 5).
Results: Thirty-four patients with a median age of 70 (range, 60-83) years were treated, with 17 each receiving either tosedostat/cytarabine or tosedostat/decitabine. Twenty-nine patients (85%) had AML and 5 (15%) had MDS RAEB-2. Nineteen patients (56%) had cytogenetics with intermediate-risk, 14 (41%) adverse-risk, and 1 (3%) favorable-risk by European Leukemia Net criteria. Seven patients had FLT3/ITD mutations with normal cytogenetics. Fifteen patients (44%) had secondary AML/MDS or antecedent hematologic disorder. The median duration of treatment was 3 months. The overall CR/CRi rate was 53% (9 in each arm), with 14 patients (41%) achieving a CR and 4 patients (12%) a CRi. CR/CRi was attained in 6 patients with adverse cytogenetics and 4 additional patients with FLT3 mutations. Fourteen patients (41%) were taken off study after a median of 2 cycles due to lack of response or disease progression. With a median follow-up of 11.2 months (range, 0.5-22.3 months), the median overall survival was 11.5 months (95% CI, 5.2-16.7). Twenty-three patients (67.6%) were treated as outpatients and 10 of these patients (44%) required hospitalization during treatment for febrile neutropenia. There were no Grade 3-4 non-hematologic toxicities requiring withdrawal from the study.
Conclusions: Tosedostat in combination with cytarabine or decitabine likely provides a CR/CRi rate of >50% with acceptable toxicity in older patients with untreated AML/ MDS. This approach delivered predominantly as outpatient therapy suggests that further study in a larger, controlled trial may be warranted.

Disclosures
Off Label Use: Pravastatin is not FDA approved for treatment of AML. Wang:CTI Biopharma: Employment. Singer:CTI BioPharma, Corp: Employment, Equity Ownership.