bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Stapled BIM BH3 Helix Restores Apoptosis In Bim-Null Mantle Cell Lymphoma
Authors: Katz Samuel G , Labelle James L , Godes Marina , Fisher Jill , Bird Gregory H. , Walensky Loren D. 
Published: October 2019

Abstract
Abstract 437
Mantle cell lymphoma (MCL) is a highly aggressive B-cell lymphoma resistant to conventional chemotherapy. Although defined by the characteristic t(11;14) translocation, a variety of genetic aberrations have been indentified in MCL and may contribute to its pathogenesis and chemoresistance. Of particular interest is the frequent biallelic deletion of the pro-apoptotic BCL-2 family protein BIM. BIM exerts its pro-death function via its alpha-helical BH3 death domain that has the dual capacity to inhibit anti-apoptotic proteins such as BCL-2 and MCL-1 and directly trigger pro-apoptotic proteins such as the mitochondrial executioner BAX. In an effort to replace the deleted BH3 functionality in Bim−/− MCL, we generated stabilized alpha-helix of BCL-2 domains (SAHBs) modeled after the BIM BH3 alpha-helix. BIM SAHBs are helical, protease-resistant, and cell permeable peptides that recapitulate the pro-apoptotic activity of BIM. Indeed BIM SAHB, but not a negative control point mutant, dose-responsively activated caspase 3/7 and correspondingly inhibited the viability of a panel of MCL cell lines with IC50s in the single digit micromolar range. To extend these studies to an in vivo model of Bim−/− lymphoproliferative disease, we reconstituted Rag2-deficient mice with the bone marrow from Bim−/− mice and documented the development of splenomegaly and massive organ infiltration by B220-positive lymphocytes. Mice treated with intravenous BIM SAHB exhibited TUNEL positivity within the aberrant organ infiltrates, but not in the surrounding normal parenchyma. Importantly, vehicle and point mutant SAHB had no such effect, highlighting the specificity of BIM SAHB activity. Thus, therapeutic replacement of BIM's pro-apoptotic functionality using BIM SAHB has the potential to restore apoptosis in hematologic cancers that mount an apoptotic blockade by deleting Bim.

Disclosures:
Walensky: Aileron Therapeutics: Consultancy, Equity Ownership, Membership on an entity's Board of Directors or advisory committees.
Indications for Platelet Transfusions: How Well Do Physicians Comply with Professional Guidelines
Authors: Katz Elena , Klek Malgorzata , Levine Randy L. , Graham Robert E 
Published: October 2019

Abstract
Abstract 4402

Background:
Professional, evidence-based guidelines are developed to help physicians implement best practice care. Unfortunately, guidelines are not followed. Platelet transfusion guidelines have recently changed to a prophylactic transfusion threshold of 10, 000/μ L from the older threshold of 20,000/μ L. We conducted a retrospective analysis at a metropolitan teaching hospital to assess how well physicians comply with the new professional guidelines as well as the older, less stringent criteria to administer platelet transfusions.

Methods:
All patients admitted to the medical service who received platelet transfusions over a two month period in 2010 were reviewed. These patients represented the following services: ICU, general medicine, medical step down, interventional cardiology, CCU, and the cardiac step down unit. The indication selected in the computerized physician order entry (CPOE) system was compared to the clinical indication found in the patients’ medical record. The medical record clinical indication was then evaluated against the American Society of Hematology (ASH) 2007 “Evidence-Based Platelet Transfusion Guidelines” (Slichter SJ. Hematology 2007): bleeding and platelets ≤50, 000/μ L, pre-invasive procedure and platelets ≤50, 000/μ L, prophylactic transfusion for platelets ≤10, 000/μ L and WHO bleeding grade ≥ 2. We also assessed how the patients’ clinical indication met the older less stringent prophylactic threshold for platelet transfusion of ≤20, 000/μ L laid forth by the landmark study by Gaydos LA. et. al. (The quantitative relation between platelet count and hemorrhage in patients with acute leukemia. N Engl J Med 1962).

Results:
A total of 108 patients received platelet transfusions; 29 were medicine patients to tally 95 platelet transfusions. The most common patient clinical indication was “platelets ≤ 20, 000/μ L without bleeding” (27%), while the clinical indication was not specified in 16% of cases. The CPOE documented indication coincided with the patient's clinical indication from the medical record in 23% of cases. Sixty five percent of the time the patient's clinical indication failed to meet the currently accepted 2007 ASH guidelines and 36% of cases failed to meet the older less stringent guidelines.

Conclusions:
A majority of platelet transfusions did not meet the current professional guidelines for indication. Our pilot study suggests the need for more physician education regarding evidence-based guidelines for platelet transfusions, and in a larger context, initiatives to enhance compliance. We are currently developing an educational intervention and plan to reassess compliance with indications pre and post intervention.

Disclosures:
No relevant conflicts of interest to declare.
The Interaction of Soluble Phospholipids with Coagulation Factor VIIa
Authors: Sengupta Tanusree , Majumder Rinku , Lentz Barry R. 
Published: October 2019

Abstract
Abstract 4421
Factor VIIa (fVIIa) is one of the key proteins in the blood coagulation cascade. It activates factors IX and × on a negatively charged phospholipid surface in either a TF-dependent or TF-independent fashion (Silverberg et al, 1977; Bom et al, 1990). Monroe et al (1997) demonstrated that fVIIa binds to activated platelets independent of TF and partially restores thrombin generation in an in vitro model of hemophilia. Thus, it appears that interaction of fVIIa with platelet phospholipids plays an important role. We report that binding of 1,2-dihexanoyl-sn-glycero-3-phospholipids -L-serine (C6PS) and 1,2-dihexanoyl-sn-glycero-3-phosphoethanolamine (C6PE) to fVIIa causes changes in its activity as well as structure. Titration with C6PS led to changes in intrinsic fluorescence indicative of two or more binding sites for this lipid. Similar titrations with C6PE indicated that it probably binds to a single site on the protein. Experiments are underway to test this initial conclusion. Both lipids bind with comparable affinity (kd ~ 165 and 160 μ M) when data were analyzed using a single site model. We also examined the effect of the soluble lipids on the activity of fVIIa. Both C6PS and C6PE binding increased fVIIa proteolytic and amidolytic activity, with the effect of C6PS being more pronounced. Based on current data, it appears that both lipids bind to a single weak site, but that binding of either to this site promotes binding of C6PS to a second, tighter, and C6PS-specific site, which seems to be crucial in regulating activity. Further experiments are underway to test this hypothesis.

Disclosures:
No relevant conflicts of interest to declare.
A Novel Case of Hemophilia B Due to a Partial Duplication of the Factor 9 Gene
Authors: Wheeler Ruth , Alamelu Jayanthi , Cutler Jacqueline 
Published: October 2019

Abstract
Abstract 4423
Hemophilia B is an X-linked recessive coagulation disorder. The disease is caused by a deficiency of procoagulant Factor IX and is characterised by easy bruising and prolonged bleeding and oozing after injury or surgery. The severity of the disease and the frequency of bleeding events vary, depending on the FIX clotting activity, and in severe cases males suffer from spontaneous joint and muscle bleeds which significantly impact on their health and quality of life. Hemophilia B is less common than Hemophilia A, with a frequency of approximately 1 in 25000 males worldwide. The F9 gene is located on the long arm of the × chromosome at Xq27. The gene comprises 8 exons, spanning approximately 33.5 kb DNA. The molecular basis of Hemophilia B is heterogeneous and to date over a 1000 different mutations have been reported, including missense and nonsense mutations, splicing mutations and large deletions. Here we report the identification of a previously uncharacterised duplication spanning a large part of the F9 gene in a patient with severe Hemophilia B. The patient, a 6 year old male of mixed Iranian and UK origin, was referred to the centre with severe Hemophilia B. He had a FIX level of less than 1iu/dL. No family history of bleeding diathesis could be confirmed due to loss of maternal family members in an earthquake. Mutation analysis of all exons including immediate flanking regions to allow detection of splice site mutations, and the 5’ and 3’ untranslated regions was performed by direct sequencing but no changes from the normal sequence were identified. There have been several reports of Hemophilia B being associated with partial duplications of the F9 gene so we analysed gene copy number using multiplex ligation-dependant probe amplification (MLPA). A large duplication, involving exons 2 to 6 was identified in the affected male. Subsequent analyses of maternal samples were normal, indicating that the mutation arose de novo.

Disclosures:
No relevant conflicts of interest to declare.
Induction of Apoptosis In Imatinib-Resistant BCR-ABL1-Positive Leukemia Cell Lines by Bortezomib
Authors: Quentmeier Hilmar , Eberth Sonja , Romani Julia , Zaborski Margarete , Drexler Hans G. 
Published: October 2019

Abstract
Abstract 4469
The BCR-ABL1 translocation occurs in chronic myeloid leukemia (CML) and in 25% of cases with acute lymphoblastic leukemia (ALL). We screened a panel of BCR-ABL1 positive cell lines to find models for imatinib-resistance studies. Five of 19 BCR-ABL1 positive cell lines were resistant to imatinib-induced apoptosis (KCL-22, MHH-TALL1, NALM-1, SD-1, SUP-B15). None of the five resistant cell lines carried mutations in the kinase domain of BCR-ABL1 and – consequently – all also showed resistance to the second generation kinase inhibitors, nilotinib or dasatinib. All Philadelphia chromosome (Ph)-positive cell lines demonstrated constitutive phosphorylation of STAT5 and S6. Imatinib induced dephosphorylation of both BCR-ABL1 downstream effectors in responsive cell lines, but - remarkably – induced dephosphorylation of STAT5 in resistant cell lines as well. By administering well-described signalling pathway inhibitors we were able to show that activation of mTOR complex 1 was responsible for the constitutive S6 phosphorylation of imatinib-resistant cells. Neither BCR-ABL1 nor Src kinases or Ras/Rac-GTPases underlie tyrosine kinase inhibitor resistance in these cell lines. In conclusion, none of the five TKI-resistant cell lines showed aberrant activation of previously-described oncogenic pathways which would explain their resistance. These findings raise the question whether these cell lines might help to find a novel – alternative – explanation for TKI resistance. Interestingly, the proteasome inhibitor bortezomib induced apoptosis in TKI-resistant and –sensitive Ph+ cell lines. Bortezomib is being used for the treatment of multiple myeloma. Our findings support the notion that bortezomib might also be useful for the treatment of imatinib-resistant CML.

Disclosures:
No relevant conflicts of interest to declare.
A Cell Line SYRMO Derived From AML with EVI 1 Rearrangements Following Imatinib Mesylate Therapy for Chronic Myeloid Leukaemia
Authors: Kottaridis Panagiotis , Brazma Diana , Howard-Reeves Julie , Mazzullo Helen , Nacheva Elisabeth P 
Published: October 2019

Abstract
Abstract 4470
Chronic Myeloid Leukaemia (CML) is a malignant disorder of the haematopoeitic stem cell, usually characterised by the t(9;22) giving rise to the Philadelphia chromosome (Ph), and by the BCR-ABL gene rearrangement at the molecular level. Imatinib mesylate (IM), which targets the tyrosine kinase (TK) activity of BCR-ABL, has become the first line therapy for CML patients. Dasatinib or Nilotinib is now indicated as a second line therapy for patients who develop resistance or intolerance to IM.
Here we report the case of a 51 year old woman who was diagnosed in Cyprus (2007) with BCR/ABL1 positive CML. After failing to respond to IM therapy, she was treated with Dasatinib achieving complete cytogenetic remission (CCR), and subsequent complete molecular remission. In July 2009 the patient presented with 88% blasts in the bone marrow. Immunophenotyping showed the presence of CD34+, CD117+ myeloblasts, and a diagnosis of AML was confirmed. Analysis of G banded metaphases from cultured peripheral blood revealed a complex karyotype: 46,XX, t(2;3)(p21;q26),t(4;8)(q12;q22), del(6)(q13;q23)[1]/45,idem,der(6)ins(6;6)(q23;),-7[9]. FISH revealed EVI 1 rearrangement resulting from the t(2;3) in the absence of BCR/ABL1 fusion and confirmed the secondary monosomy 7. The patients failed to respond to treatment and passed away shortly afterwards. Whole genome screening by aCGH using a 244K platform (Agilent) confirmed the loss of chromosome 7 and the 6q22/23 region.
Clonal cytogenetic abnormalities (CCA) in Ph-negative metaphases are known to develop in some patients during IM therapy. The most frequent of these abnormalities are trisomy 8, -7, del(7q), and del(20q), which are also associated with MDS and AML. These abnormalities are usually transient and disappear after a short time, or have no clinical consequence (Deininger et al., Cancer 2007). However, reports of development of high risk MDS or AML in association with CCA in Ph-negative cells are rare, but patients with chromosome 7 abnormalities appear to be at greater risk. The t(2;3) is a non random abnormality in MDS and AML, including therapy-related leukaemias, frequently associated with -7 and a complex karyotype with a poor prognosis (Stevens-Kroef et al Leukemia 2004).
This is the first report of a CML patient on TKI treatment with t(2;3) and EVI1 gene rearrangements in Ph(-) cells. This cryptic translocation could easily be overlooked in the presence of a monosomy 7 with a dramatic effect on patient management.

Disclosures:
No relevant conflicts of interest to declare.
Incidence and Clinical Features of Idiopathic Pneumonia Syndrome and Diffuse Alveolar Hemorrhage After Unrelated Cord Blood Transplantation.
Authors: Nishida Aya , Wake Atsushi , Yamamoto Hisashi , Ishiwata Kazuya , Nakano Nobuaki , Tsuji Masanori , Asano-Mori Yuki , Uchida Naoyuki , Izutsu Koji , Masuoka Kazuhiro , Yoneyama Akiko , Makino Shigeyoshi , Taniguchi Shuichi 
Published: October 2019

Abstract
Abstract 4535
Incidence and clinical features of idiopathic pneumonia syndrome and diffuse alveolar hemorrhage after unrelated cord blood transplantation.
Aya Nishida 1, Atsushi Wake 1, Hisashi Yamamoto 1, Kazuya Ishiwata 1, Nobuaki Nakano 1, Masanori Tsuji 1, Yuki-Asano Mori 1, Naoyuki Uchida 1, Koji Izutsu 1, Kazuhiro Masuoka 1, Akiko Yoneyama 3, Shigeyoshi Makino 4, Shuichi Taniguchi 1.
1 Department of Hematology, Toranomon Hospital, Tokyo, Japan; 2 Department of Pathology, Toranomon Hospital, Tokyo, Japan; 3 Department of Infectious Diseases, Toranomon Hospital, Tokyo, Japan; 4 Department of Transfusion Medicine, Toranomon Hospital, Tokyo, Japan [Background] Idiopathic pneumonia syndrome (IPS) and diffuse alveolar hemorrhage (DAH) are non-infectious pulmonary complications of hematopoietic stem cell transplantation (HSCT) with unclear pathogenesis and treatment. [Objective and method] To investigate the incidence and clinical features of IPS/DAH after unrelated cord blood transplantation (uCBT), we retrospectively analyzed 370 patients underwent uCBT from January 2005 to June 2010 at Toranomon Hospital. Diagnosis of IPS/DAH was made by multilobar infiltrates on CXR or CT, clinical signs of pneumonia: cough, dyspnea, or rales, abnormal physiology: increased arterial-alveolar oxygen gradient, or the needfor supplemental oxygen support, and no evidence of respiratory tract infection. [Result:] Twenty five cases of IPS/DAH were identified, with incidence of 6.8%. The median-age was 59 years (range; 26–72). Nineteen patients underwent transplantation for leukemia, 4 for malignant lymphoma, and 2 for aplastic anemia. IPS/DAH was diagnosed at a median of 34 days (range; 8–93) after uCBT. All patients were administered mPSL therapy. Nine of 25 patients were administered etanercept combined with mPSL pulse therapy. Five of 9 had not responded, while 4 responders had worse their respiratory condition after discontinuation of etanercept therapy. Twenty four of 25 died of respiratory failure. [Conclusion] IPS/DAH after uCBT are fetal pulmonary complications. It is suggested that the incidence of IPS/DAH after uCBT appears similar to that observed after transplantation using other sources. But our results suggested that the existing treatment such as etanercept combined mPSL pulse have only limited efficacy as a therapy for IPS/DAH after uCBT. Further research is needed to characterize the condition of this syndrome and to investigate the optimal therapy and prophylaxis.

Disclosures:
No relevant conflicts of interest to declare.
HSCT PATIENTS with HHV6 Reactivation HAD LOW NUMBERS of CD4+ Effector Memory Lymphocytes IN BLOOD WHAT Associates with Rather POOR SURVIVAL.
Authors: Lange Janusz , Drabczak-Skrzypek Daria , Dlubek Dorota , Jaskula Emilia , Wolowiec Dariusz , Lange Andrzej 
Published: October 2019

Abstract
Abstract 4555
It is known that the pace of immunological recovery influences the outcome of HSCT and herpes viruses reactivation contributes significantly to the post transplant mortality.
The aim of this study was to investigate reconstitution of subpopulations of CD4+ lymphocytes in the context of β-herpes viruses reactivation shortly post HSCT. There were two observation points: (1) at the beginning of lymphocyte recovery (number of lymphocytes > 200 cells/ul) which was seen from 9 to 31 day post HSCT median 14 and (2) 3 weeks later (median day 35 range(31-53)). CD4+ T cell subsets were defined as follow: Naive cells (N) CD4+CCR7+CD45RA+, Central memory (CM) CD4+CCR7+CD45-, Effector memory(EM) CD4+CCR7-CD45+, Terminally differentiated memory cells (TEMRA) CD4+CCR7-CD45RA+ . CMV, EBV and HHV-6 DNA copies were detected in blood with the use of QT-PCR in one week intervals. The study included 44 patients (age 1 to 64 median 45yr., 21 ric/mac, 21/23, sib/mud 21/23 mud, BM/PBPC 4/40.
It was found;
1. Fifteen, 13 and 4 patients were positive for EBV, HHV-6 and CMV DNA copies during the observation period.
(i) CD4+lymphocyte count was lower in patients having CMV copies as compared to those having EBV and/or HHV6 copies (both lymphocytotropic viruses) at the beginning of lymphocytes recovery (45/ul vs 120/ul p=0,047 Mann-Whitney U test), similarly behaved EM cells. 22/ul vs 84/ul EM cells (p= 0,088 Mann-Whitney U test) were seen in pts having CMV reactivation and in those with EBV and/or HHV-6 reactivation, respectively.
(ii) The situation changed three weeks later, it appeared that patients having HHV6 reactivation any time during the observation period had lower CD4+ lymphocyte numbers as compared to patients lacking β-herpes viruses reactivations (CD4+ cells median 93/ul vs190/ul; p=0,096 Mann-Whitney U test) and to those with CMV and EBV reactivation. Again EM cells contributed greatly to these differences. EM CD4+ lymphocytes were 41/ul, 105/ul, 80/ul and 160/ul in patients having HHV-6, CMV or EBV and lacking beta-herpes viruses reactivation, respectively. EM CD4+ lymphocyte numbers for HHV6+ patients as compared to patients lacking β-herpes viruses reactivations was 41/ul vs155/ul.(p=0,012 Mann-Whitney U test).
Conclusions: It appears that HHV6 is the main player in shaping lymphocyte reconstitution post transplant affecting predominantly EM cells what influences the outcome of transplantation. In this group of patients probability of one year survival was 50% vs 65%, in patients having and lacking HHV6, respectively.

Disclosures:
No relevant conflicts of interest to declare.
DynaChip Anti-HLA Antibody Analysis In Sera of Patients Following Allo-HSCT From HLA-Mismatched Unrelated Donors.
Authors: Markiewicz Miroslaw , Siekiera Urszula , Kruzel Tomasz , Dzierzak-Mietla Monika , Zielinska Patrycja , Kyrcz-Krzemien Slawomira 
Published: October 2019

Abstract
Abstract 4575

Introduction:
Anti-HLA antibodies constitute potentially important factor that may influence outcomes of HLA-mismatched allogeneic hematopoietic stem cell transplantation (allo-HSCT). The rationale of this study was to detect presence of anti-HLA antibodies in recipients of allo-HSCT from HLA-mismatched unrelated donors.

Patients and Methods:
Anti-HLA-A,B,C,DR,DQ,DP antibodies were identified in sera collected from 46 recipients of allo-HSCT from HLA-mismatched unrelated donors. Sera were collected between 1 month and 5.5 years after allo-HSCT, and additionally before allo-HSCT in 17 pts. We have used microchips spotted with purified HLA class I and HLA class II antigens to allow binding of anti-HLA antibodies present in tested sera to the surface of the microchip, pre-optimised reagents and DynaChip Processor (Dynal Invitrogen Corporation) for assay processing, data acquisition and analysis.

Results:
Antibodies against HLA class I, II or I and II were detected in 15%, 11% and 35% of pts whereas no antibodies were detected in 39% of patients. Antibodies were directed against HLA-A, B, C, DR and DQ in 37%, 46%, 35%, 48% and 35% of pts, respectively. Pre-transplant anti-HLA antibodies have been detected in 7 pts (41%) out of 17 tested before allo-HSCT. In this group percent of Panel Reactive Antibodies (% PRA) increased following allo-HSCT in 3 pts and decreased in 4. In 5 out of 10 remaining pts without pre-transplant antibodies, %PRA increased post-transplant. DynaChip software allowed to define specificities of HLA-A,B,C,DR and DQ antibodies on low and high resolution levels. The specificity of antigens that masked results of antibody identification has been also defined in 2 pts. At this stage we did not define exactly whether detected anti-HLA antibodies were donor-specific. Cross-reactive groups (CREG's) analysis has been also used to compare antibodies’ reactivity. Anti-HLA-DP antibodies were not detected in the examined group of transplanted patients.

Conclusions:
Presented preliminary study results indicate, that anti-HLA antibodies can appear post-transplant in mismatched allo-HSCT recipients. Further analysis aiming to evaluate their influence on transplant outcomes is ongoing. We intend to extend the search for anti-HLA antibodies with use of Luminex LabScreen method.

Disclosures:
No relevant conflicts of interest to declare.