bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of An Automatic Washing Method for DMSO Cryopreserved Peripheral Blood Hematopoietic Progenitors Using the Sepax S-100.
Authors: Blanquer Miguel , Cabañas-Perianes Valentín , Majado Maria Juliana , Ibáñez Victoria Sánchez , Sánchez Pilar Menchón , Monserrat Jorge , Lázaro Alfonso Morales , Moraleda Jose Maria 
Published: October 2019

Abstract
Abstract 3219
Poster Board III-156

Introduction
Dimethylsulfoxide (DMSO) containing cryoprotective solutions are routinely used for the storage of hematopoietic progenitors (HP). At room temperature, DMSO is toxic for the cells and may produce severe adverse reactions during their infusion, especially in the pediatric patients. These problems can be avoided by washing the cells prior to the infusion. Our objective was to test if an automatic washing method (Sepax S-100, Biosafe) allowed us to preserve the CD34+ cell numbers with an adequate viability and engraftment potential.

Material and Methods
Forty five peripheral blood HP apheresis that have been cryopreserved using autologous plasma plus 9% DMSO were studied. After rapid thawing in a water bath at 37° C, an automatic wash with the Sepax S-100 (2 washes cycle) was performed. Nucleated cell levels determined by an hematology analyzer, flow cytometry CD34+ cell counts and Trypan Blue cell viability test were performed on aliquots collected prior to and after the washing technique. The paired Student's t-test and the Pearson's correlation coefficient were used for the statistical analysis.

Results
The mean total nucleated cell (TNC) and CD34+ cell recovery was 75,47% ± 3, and 94,66% ± 4,62 respectively. In spite of the TNC significant loss (p<0,001), there were no significant differences between the pre and post-washing CD34+ cell numbers (p=0,08) or viability (p=0,19). The TNC loss had no correlation with the pre or post-washing number of platelets (p=0,18 and p=0,16 respectively), neither with the loss of platelets during the procedure (p=0,31). In contrast with the 40% of untoward reactions recorded in our historical data of 226 DMSO containing cell infusions, we observed just one adverse effect (2,22%) with the washed cells. One patient reported a transient mild abdominal pain with nausea and one vomit. Median time to neutrophil engraftment (>500 cells /mL) and platelet engraftment (>50.000 cells/mL) were 11 ± 0,2 and 20 ± 1,4 days respectively.

Conclusions
The Sepax S-100 automatic wash protocol of DMSO containing peripheral blood progenitor cells determines a good CD34+ cell recovery and preserves their viability and engraftment potential. This method avoids the DMSO infusion related adverse events and it constitutes a closed and easy to do procedure.

Disclosures
No relevant conflicts of interest to declare.
Diagnosis of Invasive Fungal Infections by a Real-Time Panfungal PCR Assay in Pediatric Patients Undergoing Intensive Chemotherapy or Allogeneic Stem Cell Transplantion.
Authors: Landlinger Christine , Baskova Lenka , Preuner Sandra , Grotel Martine Van , Hartwig Nico G. , Heuvel Marry M. van den , Lion Thomas 
Published: October 2019

Abstract
Abstract 343
Invasive fungal infections are life threatening events in severely immunocompromised patients, and there is urgent need for reliable screening methods facilitating rapid and broad detection of pathogenic fungi. We have established a two-reaction real-time PCR assay permitting highly sensitive detection and quantitative monitoring of more than 80 fungal pathogens, covering a large spectrum of moulds, yeasts and Zygomycetes (European patent No. 06817468.9). To assess the clinical potential of the panfungal real-time PCR assay, more than 600 consecutive specimens from 126 pediatric patients carrying a high risk of invasive fungal infections were analyzed. The results revealed an excellent correlation between PCR positivity and the presence of proven, probable or possible fungal infection according to the criteria of the European Organization for Research and Treatment of Cancer (EORTC), indicating a sensitivity of the assay of 96% (95%CI: 81-99.3%). Hence, the negative predictive value of the panfungal PCR assay presented is very high, and our current data indicate that molecular screening of patients during febrile neutropenic episodes by the assay can help prevent unnecessary toxicity resulting from empirical antifungal treatment in individuals who may not be at risk of imminent fungal disease. The specificity of the assay in the test cohort of patients was in the range of 76% (95%CI:62-87%), and the observations indicate that rapid species identification may be required to assess the positive predictive value for impending fungus-related disease. The availabel data provide a basis for appropriately designed clinical studies addressing the full diagnostic potential of fungal screening by highly sensitive, broad- spectrum molecular assays in severely immunocompromised patients.

Disclosures:
No relevant conflicts of interest to declare.
Long-Acting Interleukin-11 Shows Improved Activity to Increase Platelet Numbers.
Authors: Jung Yuni , Ahn Haesook , Kim Dong-Sik , Hwang Yu Ri , Ho Seong-Hyun , Kim Sujeong , Kim Jong-Mook 
Published: October 2019

Abstract
Abstract 3512
Poster Board III-449
Often the clinical efficacy of a therapeutic protein relies on the structural stability, bioavailability, and clearance rate of the protein. The current work presents greatly improved efficacy of human interleukin-11 mutein conjugated with single polyethylene glycol polymer (PEG-mIL-11). The interleukin-11 mutein (mIL-11) is newly redesigned human interleukin-11 to endure chemical and proteolytic stresses while retaining all the biological activities, which reduces chance of causing side effects in clinics. The interleukin-11 mutein is currently under phase II clinical trial in China to evaluate ability to increase platelet counts after chemotherapy. Further, single methoxy-polyethylene glycol succinimidyl carbonate was attached onto mIL-11 via surface exposed amines to prolong the circulation time in vivo. Unlike often observed cases with other PEGylated proteins, the attached bulky PEG provided no hindrance to the receptor binding of IL-11, when in vitro cell proliferation activity was monitored on Ba/F3 cells expressing IL-11 receptors. Interestingly, single subcutaneous administration of PEG-mIL-11 showed higher efficacy to increase platelet counts than daily subcutaneous administration of unmodified mIL-11 of same dosage for 7 days in rats. The pharmacokinetic profile of PEG-mIL-11 was monitored after single subcutaneous injection in rats. The half-time (t1/2), time to reach the maximum level (Tmax), and bioavailability (area-under-curve) of PEG-mIL-11 increased 5-, 6- and 5-fold as compared to the values of unmodified mIL-11 of same dosage, respectively. Mono-PEGylated IL-11 mutein demonstrated not only the prolonged circulation time but also the retained biological activity, thereby the possibility for clinical applications such as the treatment or prevention of the chemotherapy-induced thrombocytopenia.

Disclosures:
No relevant conflicts of interest to declare.
The Role of Hematopoietic Cell Transplantation (HCT) for Burkitt Lymphoma: a Report From the Center for International Blood and Marrow Transplant Research (CIBMTR)
Authors: Gajewski James L. , Carreras Jeanette , Lazarus Hillard M. , Laport Ginna G. , Montoto Silvia , Maloney David G. , Hari Parameswaran 
Published: October 2019

Abstract
Abstract 2390
Burkitt lymphoma (BL) is an aggressive B cell lymphoma primarily affecting children and young adults and is characterized by the highest doubling time of any tumor. Cyclical intensive chemotherapy and rituximab confer high complete remission (CR) rates and 80% long term disease free survival in chemotherapy sensitive disease. The role of autologous (autoHCT) or allogeneic (alloHCT) transplant is not well described in BL. We report the outcomes of 241 recipients of HCT for BL between 1985 and 2007 reported to the CIBMTR. Five patients (pts) received syngeneic twin grafts in addition to autoHCT in 113 pts, HLA identical sibling alloHCT (SIB) in 80 pts and mismatched related or unrelated donor (UNR/MM) alloHCT in 48 pts. Baseline patient and disease related risk factors varied significantly between cohorts (table1). The autoHCT cohort had a higher proportion of pts with chemotherapy sensitive disease (86%), peripheral blood grafts (73%) and HCT in first CR (42%). In the UNR/MM cohort, 25% pts were chemotherapy resistant and only 6% were in CR1. The use of autoHCT has declined in recent years with the majority (81%) performed before 2001. Conditioning regimen for alloHCT was myeloablative in 88% (86% and 92% in SIB and UNR/MM respectively). Treatment related mortality (TRM) was higher in alloHCT recipients (table1). Cumulative incidence of relapse/progression at 5 yrs (95% CI) was 44 (35-53)% for autoHCT, 42(31-53)% for SIB and 48 (34-62)% for UNR/MM. For autoHCT, 5-yr progression free survival (PFS) was 48(39-58)%, 78% for those in first CR versus 27% for disease beyond CR1 (p<0.001). For alloHCT, 5-yr PFS was 50% for those in first CR versus 19% for disease beyond CR1 (p=0.001) (figure 1). 5-yr PFS was 30 (20-41)% for SIB and 22 (12-35)% for UNR/MM. Progressive BL was the commonest cause of death.

Conclusion:
While autoHCT and alloHCT are both feasible in patients with BL, the use of autoHCT appears to be declining in recent years concomitant with the advent of modern chemotherapy. AlloHCT was performed in those with considerably higher risk disease. Approximately one fifth of advanced BL pts receiving alloHCT beyond CR1 had long term disease free survival.

Disclosures:
No relevant conflicts of interest to declare.
Low-Dose Fludarabine and Cyclophosphamide Combined with Rituximab In the Treatment of Elderly/Comorbid Patients with chronic Lymphocytic Leukemia/Small Lymphocytic Lymphoma (CLL/SLL): Preliminary Results of Project Q-Lite by Czech CLL Study Group
Authors: Smolej Lukas , Spacek Martin , Brychtova Yvona , Belada David , Schwarz Jiri , Doubek Michael , Motyckova Monika , Cmunt Eduard , Rohon Peter , Klaskova Katerina , Kozak Tomas 
Published: October 2019

Abstract
Abstract 2466

Background:
Combination of fludarabine, cyclophosphamide and rituximab (FCR) is currently considered the treatment of choice in physically fit patients (pts) with chronic lymphocytic leukemia (CLL). However, many patients cannot tolerate this aggresive treatment because of advanced age and/or serious comorbid conditions. For these patients, chlorambucil has remained so far the standard of treatment. Low-dose fludarabine-based regimens have recently demonstrated promising results in small studies.

Aims:
to assess efficacy and safety of low-dose FC or FCR regimen used in elderly/comorbid patients with CLL.

Patients and Methods:
Between March 2009 and June 2010, we treated 74 pts with active disease (CLL, n=70, SLL, n=4, 57% males, median age, 70 years [range, 58–83], median Cumulative Illness Rating Score 4 [range, 0–10]) by low-dose FC/FCR at fourteen centers cooperating within Czech CLL Study Group. Dose reduction of chemotherapy was as follows: fludarabine to 50% (12 mg/m2 i.v. or 20 mg/m2 orally on Days 1–3), cyclophosphamide to 60% (150mg/m2 i.v./p.o. D1-3). The dose of rituximab was standard (375mg/m2 in 1st cycle, 500mg/m2 from 2nd cycle). The choice of regimen (FC vs FCR) was at the discretion of the attending physician. Treatment was repeated every 4 weeks. Antimicrobial prophylaxis with cotrimoxazole and aciclovir or equivalents was recommended. Fifty per cent of pts were treated in first line, the remaining half had relapsed/refractory CLL. Rai stage III/IV was present in 57% pts; 39% had bulky disease. IgVH genes were unmutated in 74%; according to hierarchical model, del 11q was present in 32% and del 17p in 8%.

Results:
FCR was used in 72 pts, FC in 2. Based on intention-to-treat principle, the overall response/complete response rate (including clinical CR and CR with incomplete blood count recovery) was 70/35%; 34 pts are still on treatment. No data on PFS/OS are available yet. Serious (CTC grade III/IV) neutropenia occurred in 51%, thrombocytopenia in 13% and anemia in 10% of pts. Serious infections were diagnosed in 13% of pts. Three pts (4%) died, all of them after failure of treatment (pneumonia, n=2, pulmonary embolism, n=1).

Conclusions:
Treatment of elderly/comorbid CLL patients with low-dose FC/FCR demonstrated very promising results. Toxicity was acceptable and manageable. Longer follow-up is needed for the assessment of PFS and OS. Supported by research project MZO 00179906 from Ministry of Health, Czech Republic.

Disclosures:
Smolej: Roche: Honoraria; Bayer-Schering: Honoraria; Genzyme: Honoraria. Off Label Use: Low-dose FCR in elderly/comorbid patients with CLL. Belada: Roche: Consultancy, Honoraria. Motyckova: Roche: Honoraria.
Recurrent Mutations Found In Acute Monocytic Leukemia by Exomes Sequencing
Authors: Yan Xiao-Jing , Xu Jie , Gu Zhao-Hui , Pan Chun-Ming , Lv Gang , Li Keqin Kathy , Mi Jian-Qing , Yang Shen , Song Huai-Dong , Chen Sai-Juan , Chen Zhu 
Published: October 2019

Abstract
Abstract 2490
Acute monocytic leukemia, the M5 subtype of acute myeloid leukemia (AML-M5), is a distinct group with characteristic clinical features and has been reported to have a poor prognosis. A subset of AML-M5 is associated with various chromosomal translocations involving the MLL locus at 11q23, while mutations are also reported in genes such as NPM1, FLT3, NRAS at different frequencies in this disease. However, these genetic changes occur only in a part of AML-M5 patients and some of them lack specificity due to the presence in other AML subtypes. To address the important genetic and molecular factors for the pathogenesis of M5 in a comprehensive manner, we sequenced exomes from nine AML-M5 initial bone marrow (BM) samples and matched control samples. We identified 64 somatic mutations within the coding sequences of 61 genes including 57 point mutations and 7 insertions or deletions (indels), among which 17 genes had at least 2 cases of mutations in 100 validated AML-M5 BM samples. We tested a part of these gene mutations in different subtypes of AML and found that some mutations are restricted to AML-M5 and AML-M4 (acute myelomonocytic leukemia) with more than 15% and 10% frequency, respectively. Thus, by systemic sequencing of exomes from a group of AML-M5 cases, we discovered recurring mutations that may play an essential role in the pathogenesis of AML with monocytic features.The prognostic significance of the mutations will be present in details.

Disclosures:
No relevant conflicts of interest to declare.
Macrothrombocytopenia and Hemolysis Associated with Phytosterolemia
Authors: Wang Gaifeng , Wang Zhaoyue , Cao Lijuan , Jiang Minghua , Bai Xia , Ruan Changgeng 
Published: October 2019

Abstract
Abstract 2515

Objective:
Phytosterolemia is a rare autosomal recessive sterol storage disease, characterized by increased serum concentrations of plant sterols (phytosterols). It is caused by gene mutations of ABCG5 and ABCG8. The patients suffer from xanthomas and premature atherosclerosis. In this study we demonstrate that macrothrombocytopenia and hemolysis are intrinsic features in four unrelated patients with phytosterolemia, and their clinical and pathogenesis are investigated.

Methods:
Erythrocyte and platelet morphology was examined under light microscope. Platelet aggregation was measured turbidometrically. Platelet glycoproteins were analyzed using flow cytometry. Biochemistry was analyzed by routine methods. The plasma sterol levels were measured by HPLC method. ABCG5 and ABCG8 genes were directly sequenced to identify mutations, Restriction endonuclease analysis was used to exclude the possibility of gene polymorphism.

Result:
All the four patients presented xanthomas, macrothrombocytopenia, hemolysis and splenomegaly. The blood smears showed large platelets, some as large as erythrocytes and abnormal erythrocyte shapes, such as stomatocytes. All the patients had bleeding tendency. There were mild defect in aggregation induced by ADP and ristocetin. The red cells showed an increased osmotic fragility. Plasma concentrations of phytosterols including sitosterol, stigmasterol and cholestanol were markedly elevated (30 fold) in the affected patients. Patient 1 was found to be homozygous for C→T mutation at nucleotide 64 in exon 1 of the ABCG5 gene, which results in the premature termination of the ABCG5 protein at amino acid 22 (Gln22X). Patient 2 was homozygous for C→T mutation at nucleotide 1336 in exon 10 of the ABCG5 gene, which results in the premature termination of the ABCG5 protein at amino acid 446 (Arg446X). Patient 3 was compound heterozygous for a large fragment deletion at nucleotide 1842 to 1883 in exon 12, and a complex mutation of del 1938C–1939G/ins1938T in exon 13 of ABCG8. Patient 4 was also compound heterozygous for C→T mutation at nucleotide 1336 in exon 10 and A→G mutation at classical cut locus in intron 9.

Conclusion:
In this study, we identified four patients with phytosterolemia who had macrothrombocytopenia and stomatocytic hemolysis in addition to common increased plasma plant sterols and xanthomas. Gene analysis confirmed the diagnosis. We suggest that the coexisting macrothrombocytopenia and stomatocytic hemolysis represent a new subtype of phytosterolemia, and plasma phytosterols should be measured in patients who have stomatocytic hemolysis and macrothrombocytopenia (so called“Mediteranean macrothrombocytopenia/ stomatocytosis”).

Disclosures:
No relevant conflicts of interest to declare.
Important Role for flt3 Ligand In the Generation of Early B and T Cell Precursors From Human Primitive Hematopoietic Progenitors, Revealed by Telomerized Human Stromal Cells.
Authors: Liu Bing , Ohishi Kohshi , Masuya Masahiro , Hamada Hirofumi , Katayama Naoyuki 
Published: October 2019

Abstract
Abstract 2582
The regulatory mechanism of human early T and B lymphopoiesis has not been well defined. It has been mostly studied, using mouse stromal cell lines, but either T or B lineage cells were developed. We first tested if human telomerase catalytic subunit (hTERT)-transfected telomerized human stromal cells, which have been shown to efficiently support myelopoiesis in serum-containing and serum-free cultures, are able to support the generation of T and B lineage cells from human primitive hematopoietic progenitors.
When we examined the relationship of the expression of lymphoid markers CD7, CD19, CD10, and cytoplasmic CD79a (cyCD79a) with CD38 on cord blood CD34+ cells, these antigens were mainly expressed on CD38high population. The CD19+ or CD10+ cell population mostly overlapped with the cyCD79a+ population. The CD19+ or CD10+ population was largely mutually exclusive with the CD7+ population. We therefore isolated CD34+CD38low/-CD7−CD19−CD10− cells to obtain immature hematopoietic progenitors and incubated the cells with the hTERT-stromal cells in the presence of 20%FCSaMEM. After three weeks, CD19−CD10−CD20−VpreB−cyCD79a+ early B, CD19+CD10+CD20+/−VpreB−cyCD79a+ proB, and CD7+CD56−CD2+/&minus;CD1a−cyCD3− proT stage of cells were detected, in addition to myeloid cells.
We then examined the effect of cytokines on the generation of the proB and proT cells. Addition of flt3 ligand (flt3L) to the culture led to an increase in the numbers of the early B, proB, and proT cells by 8-, 13- and 12-fold, respectively, while flt3L did not significantly affect their differentiation. On the other hand, SCF or TPO alone did not significantly affect the generation of early B, proB, and proT cells, but, in combination with flt3L, enhanced the generation of these cells. No effects were seen with IL-7. In serum-free cultures without cytokines, considerable number of CD7+ cells was detected, but few or no B lineage cells including cyCD79a+CD19− early B cells were not observed. Nevertheless, flt3L not only enhanced the generation of CD7+ cells but also induced the development of cyCD79a+CD19− early B cells.
Our data show the usefulness of telomerized human stromal cells to assess human lymphopoiesis in vitro and suggest an important role for flt3L in human early B and T lymphopoiesis in the human bone marrow environment.

Disclosures:
No relevant conflicts of interest to declare.
Neuropsychology and MRI Observational Study In An Adult Sickle Cell Disease Population In South East London
Authors: Rawle Heather , Holmes Paul , Thomas Veronica J , Cartwright Ronwyn , Howard Jo 
Published: October 2019

Abstract
Abstract 2642
We studied 36 patients attending the sickle cell clinic in our large adult population of over 600 patients. These patients presented to the sickle psychology service because they had a past history of a stroke, or presented with concerns about memory. An MRI brain scan and neuropsychological testing (including tests for IQ, processing speed, executive function and memory) were performed on each patient. The data were organised into four groups in terms of severity of MRI abnormalities: normal MRI n=13; silent cerebral infarcts (subcortical punctate small vessel cerebrovascular disease) n= 11; severe infarcts as an adult n=8; and severe infarcts as a child n=4. The majority of patients with a history of stroke had evidence of large vessel infarcts as well as features of deep watershed ischaemia seen in large vessel (distal internal carotid artery) disease. These groups did not differ significantly in terms of gender, phenotype, age and mood. Cognitive impairments were more prevalent in the severe infarct groups but were also found in patients with silent cerebral infarcts and normal MRIs. Executive functioning and processing speed deficits were evident in all groups but were more severe in the silent cerebral infarct and severe infarct groups. Chi-squared tests for trend showed that the following test scores tended to reduce as MRI abnormalities increased: Full-Scale IQ (p=0.016), Processing Speed Index (p=0.015), Trail Making Test A (p=0.014), Trail Making Test B (p=0.018), and FAS Verbal Fluency Test (p=0.006). This suggests that executive functioning, processing speed and full-scale IQ are particularly vulnerable to the effects of MRI abnormalities in this patient population. Although the cognitive impairments were more severe in the groups with abnormal MRIs, there was significant cognitive impairment in some patients with normal MRIs, suggesting that other factors are also causative of cognitive impairments. These factors may include physiological causes such as impaired perfusion, and psychosocial factors such as disruption to education. These results agree with a recent US study (Vichinsky et al, 2010, JAMA, 303, 1823–1831) showing cognitive impairment in patients with normal MRI scans which implies that MRI is not an adequate screening tool to identify patients with cognitive impairment. This study has important clinical implications in terms of how cognitive deficits can affect the effectiveness of patient – health care professional consultations, patients' ability to manage their SCD and adhere to medication and health care advice. It is important therefore to identify patients with SCD who have such cognitive impairments so appropriate support can be offered.

Disclosures:
No relevant conflicts of interest to declare.