bluuebunny/crossref_metadata_2025_split huggingface dataset:
In Vitro Deprivation of CD8+CD57+t Cells Promotes the Malignant Growth of Bone Marrow Stem/Progenitor Cells in Patients with Myelodysplastic Syndrome.
Authors: Zhang Qianqiao , Li Xiao , Zhang Zheng , Xu Feng , He Qi , Wu Lingyun , Chang Chunkang 
Published: October 2019

Abstract
Abstract 1764
Poster Board I-790

Objective
To investigate the effect of the activated CD8+T (CD8+CD57+) lymphocytes on colony formation (especially malignant colony formation) during myelodysplastic syndrome (MDS) in vitro.

Methods
Bone marrow mononuclear cells (BMNC) from a total of 54 MDS patients were subjected to magnetic-activated cell sorting (MACS) to separate CD8+CD57+T lymphocytes. BMNC were cultured without CD8+CD57+T cells or cocultured with 4 times of CD8+CD57+T cells to study the correlation between the stem/progenitor cell colony formation and the polarization of T cells towards Tc1 lymphocytes. G-band karyotyping was used to identify abnormal karyotypes in MDS patients. The fluorescence in situ hybridization (FISH) method was used to detect stem cells carrying abnormal karyotypes, and the proportions of abnormal cells among BMNC were calculated before and after T cell deprivation. The impact of effector CD8+T cells on the malignant growth of BMNC was especially investigated.

Results
(a) After deprivation of CD8+CD57+T cells, BMNC from 28 MDS patients formed colonies in the culture media. The average number of granulocyte and monocyte colony forming unit (CFU-GM) was 42.9/4×105 cells, and the average number of erythroid colony forming unit (CFU-E) was 11.36/4×105 cells, which were significantly lower than those in the normal control group after deprivation of CD8+CD57+T cells (CFU-GM 83.4/4×105 cells, CFU-E 32.8/4×105 cells; P=0.00). After add-back of CD8+CD57+T cells (4 times), none of the BMNC cultures from any of the 54 MDS patients formed colonies in vitro. (b) In 28 MDS patients whose BMNC formed colonies after T cell deprivation, the bone marrow Tc1/Tc2 ratio was positively correlated with the number of CFU-GM (r=0.463, P=0.01). (c) In 15 MDS patients who had abnormal karyotypes, deprivation of CD8+CD57+T cells significantly increased the proportion of abnormal cells from 43.79% to 56.26% in BMNC culture (P=0.00).

Conclusion
The effector CD8+T lymphocytes inhibit bone marrow hematopoiesis in MDS patients, and the target cells were mainly the cells with a malignant phenotype and abnormal karyotypes.

Disclosures
No relevant conflicts of interest to declare.
Yttrium 90 Plus High Dose BEAM Conditioning with Autologous Stem Cell Transplantation (ASCT); Effects of Prior Rituximab and Outcome of Poor Risk Non Hodgkin Lymphoma (NHL).
Authors: Krishnan Amrita , Raubitschek Andrew , Nademanee Auayporn P. , Kogut N. , Popplewell Leslie , Tsai Ni-Chun , Palmer Joycelynne , Simpson Jennifer , Federico Laura , Yamauchi Dave , Forman Stephen J. 
Published: October 2019

Abstract
Abstract 2323
Poster Board II-300

Introduction:
High dose chemotherapy with ASCT can increase overall survival (OS) in patients with poor risk or relapsed Non- Hodgkin lymphoma (NHL). Novel conditioning regimens combining radioimmunotherapy (RIT) with high dose chemotherapy have demonstrated favorable toxicity profiles and potentially improved response rates. Herein we report on 84 patients who underwent conditioning with Y90 Ibritumomab plus high dose BEAM (BCNU VP16 AraC Melphalan) and the effects of pretreatment rituximab levels on relapse. On day-23 and day-16 of conditioning pts had a blood draw for rituximab levels. If levels were &10ug/ml, pts received rituximab 250mg/m2. This was followed by pretherapy imaging with Indium 111 on day -21 and Y90 treatment on day -14. High dose BEAM chemotherapy started on day-7and all pts received rituximab 250mg/m2 at day+8.

Results:
The median age at ASCT was 58.5 years (range 19-78). Histologies included DLC n=36, Mantle Cell n=27, Follicular n=11, Transformed NHL n=10. Disease status at ASCT was 1st or 2nd CR n=35, 1stPR n=13, 1st or 2nd rel n=18, induction failure (IF) n=18. Median length of f/u for living pts was 34 months. All patients engrafted at a median of 11 days (anc>500) Transplant related mortality was 2.3 %. Two year OS/PFS for the entire cohort was 85.62% (77-91) and 66% (58-73). There was no significant difference in either DFS or OS based on histology (figure 1)Rituximab levels were available in a subset of 18 pts. and of note there was a trend towards higher relapse rates in patients with higher day-23 rituximab levels (35% vs. 0) (see figure 2).

Conclusions.
Y90 BEAM conditioning is well tolerated. Short term outcome is similar among different histologic types of NHL. The true effects of rituximab levels may not yet be fully appreciated due to small patient numbers. However, the trend towards higher relapse rates in the cohort with high circulating pre RIT rituximab levels suggests that titration of rituximab dosing pre RIT may be another strategy in which to improve transplant outcomes by optimizing targeting of the RIT.

Disclosures:
Off Label Use: yttrium 90 in combination with high dose BEAM chemotherapy.
In Vitro Activity of the Type II Anti-CD20 Antibody GA101 in Refractory, Genetic High-Risk CLL.
Authors: Zenz Thorsten , Volden Matthias , Mast Theresa , Sarno Antonio , Winkler Dirk , Schnaiter Andrea , Bühler Andreas , Klein Christian , Umana Pablo , Döhner Hartmut , Stilgenbauer Stephan 
Published: October 2019

Abstract
Abstract 2379
Poster Board II-356

Introduction:
Anti-CD20 (i.e. rituximab) based immuno-chemotherapies are now considered standard of care in CLL. However, addition of rituximab does not appear to decisively alter the dismal clinical outcome for 17p- / TP53 mutated CLL. Relatively little is known about activity of different anti-CD20 antibodies in genetic subgroups of CLL.

Methods:
In an effort to assess the activity of the next generation mAb GA101 in vitro, we studied B cell depletion / apoptosis in a set of CLL patients. CLL samples were genetically characterized with respect to genetics (genomic aberrations, TP53 mutation, IGHV mutation status), as well as clinical course and immunophenotype. To study the effect on CLL cells, we assessed GA101, Rituximab and Alemtuzumab by in vitro treatment after ficoll separation with FACS (7-AAD) for viability. In addition, in order to maintain ADCC and to mirror the in vivo situation, we studied the effect of GA101 in a whole blood culture (n=10).

Results:
With increasing concentrations (0.01-100mg/ml) of GA101 we observed significant cell death as measured by a B cell depletion assay (whole blood) after GA101 exposure (n=10). After 3 hours the maximum effect was observed at a concentration of 10mg/ml with a reduction of CLL cells to 43% of untreated cells.
The results after 8h were similar, again showing the profound effect in GA101 treated samples (mean B-cell depletion to 34.6% remaining cells). Interestingly, further increasing the dose to 100mg/ml did not increase the B-cell depletion by the antibody, but appeared to decrease the ability to deplete CLL cells (Fig. 1).
In contrast treatment with control antibodies (isotype control, rituximab, alemtuzumab) did not lead to similar B-cell depletion (101%, 69%, and 73% of control cells at 3h). We were particularly interested in any potential effect in cases with TP53 mutation. While the sample number is still low (TP53 mutation / 17p deletion n=3), currently we have no indication of differential response in different genetic subgroups.

Conclusion:
Compared to the currently most widely used mAb in CLL (Rituximab), GA101 appears more potent at equivalent concentration in depleting CLL cells. Further in vitro studies are currently ongoing to assess this antibody in particular in genetic high-risk, refractory CLL.

Disclosures:
Zenz: Roche: Honoraria. Klein:Roche: Employment, Equity Ownership, Patents & Royalties. Umana:Roche: Employment, Equity Ownership, Patents & Royalties. Döhner:Roche: Research Funding. Stilgenbauer:Roche, Bayer Schering Pharma: Honoraria, Research Funding.
Human Cytomegalovirus Inhibited Megakaryocytic Differentiation, Maturation and Induced Apoptosis in Vitro.
Authors: Chen Jian Liang , Chan Godfrey ChiFung , Ye Jie Yu , He Zheng Xian , Wang Qing Wen , Pan Si Nian , Li Xiao Feng , Deng Rui Xia , Yang Mo 
Published: October 2019

Abstract
Abstract 2413
Poster Board II-390
Human cytomegalovirus (HCMV) can cause life-threatening infection in immunocomprimised individuals, such as patients undergoing intensive chemotherapy or bone marrow transplantation. Thrombocytopenia is one of the manifestations in active HCMV infection, which may be a consequence of viral suppression on megakaryopoiesis. The exact underline mechanisms remain uncertain. Our previous studies suggested that HCMV directly infects megakaryocytic progenitors and inhibits their proliferation. Colony-formation of HCMV-infected CFU-MK decreased in a dose-dependent manner (Blood, 2003, abstract). In present study, we explored the mechanisms further by using a phorbol 12-myristate 13-acetate (PMA) stimulating polyploidization to mimic the late stage of megakaryocytic differentiation and maturation in vitro. After co-culture of a megakaryocytic cell line CHRF-288-11 with HCMV AD169 experimental strain from day 0 to day 3 (multiple of infection, MOI=1), the polyploidization of megakaryocyte was determined by DNA content analysis using flow cytometry. Compared with negative control, the proportion of polyploidy (ploidy N ≥ 8) megakaryocytes decreased by 52%, 32% and 16% in HCMV-infected cell at day 3, day 6 and day 9 respectively. As a specific receptor for megakaryopoietic differentiation, the c-Mpl protein (TPO receptor) was also examined in CHRF-288-11 cell line. The proportion of c-Mpl positive cells showed a 23% decrease in HCMV-infected group in compared to the mock infection control (using ultralviolet treated HCMV) at day 5. In addition, apoptotic signals from megakaryocytic surface, cytoplasma and mitochondria were detected in HCMV-infected cells by flow cytometry with Annexin V, Caspase-3 and JC-1 assay. Compared to mock infection control at day 5, annexin-V positive cells population increased by 57%; active caspase-3 signal increased by 125% in viable cell population; and cell population with damaged mitochondial membrane showed a 5-times increase. In conclusion, our data demonstrated that: (1) HCMV inhibited megakaryocytic differentiation and maturation at late stage; (2) HCMV reduced c-Mpl positive cell population; (3) HCMV induced megakaryocytic apoptosis through intrinsic apoptotic pathway as shown by the functional alteration of mitochodial membrane, activation of caspase-3 and structural damage of outer cellular membrane. HCMV-induced thrombocytopenia is the consequence of multiple processes involving inhibition of megakaryocytic proliferation, differentiation, maturation and also increased megakaryocytic apoptosis.

Disclosures:
No relevant conflicts of interest to declare.
The Population Based Incidence of Myelodysplastic Syndrome (MDS): Utility of Multiple Data Sources and Follow-up.
Authors: Kumar Rajat , Musuka Charles , Khair Humaira , Seftel Matthew D. , Szwajcer David , Clague Cheryl , Noonan Gail , Demers Alain 
Published: October 2019

Abstract
Abstract 245

Background:
The incidence of MDS in Canada is not known. Diagnosis of MDS is often challenging as dysplastic features on bone marrow may be non-specific, requiring exclusion of other disorders. The province of Manitoba, with a population of 1.2 million, has a cancer registry which has included patients with MDS since 2001. In this province, hematology diagnostic services are centralized at two teaching hospitals and the few bone marrows performed outside are reviewed centrally. This provided us with the opportunity to use registry data and bone marrow records to determine the incidence of MDS. We hypothesized that for an accurate estimate, a proportion of MDS cases would require follow-up data.

Methods:
Retrospective study to examine all cases of MDS, which included chronic myelomonocytic leukemia (CMML) diagnosed in Manitoba. All adult Manitobans diagnosed with MDS and CMML (excluding RAEB-T), from 01/2006 to 12/2007 were identified from the cancer registry using ICD-O-3 topography code C42.1 and morphology codes 9980/3, 9982/3, 9983/3, 9985/3, 9986/3, 9987/3, 9989/3 and 9945/3. Bone marrow records for the same period were reviewed to identify all cases that had features of MDS. The clinical charts of all these patients were reviewed centrally to exclude those whose clinical course or repeat investigations suggested an alternative diagnosis.

Results:
A total of 80 patients with newly diagnosed MDS were identified. The age adjusted incidence of MDS was 3.26/100,000. Incidence was higher in men (4.05/100,000) as against women (2.57/100,000). Incidence varied significantly with age at diagnosis: <49yr: 0.12; 50–59yr: 2.24; 60–69yr: 10.63; 70–79yr: 20.41 and >80yr: 21.93. Eleven cases (13.75%) were not known to the cancer registry but were detected on reviewing the bone marrow data. From the registry, nine cases (11.25%) were excluded as the chart review and follow-up revealed alternative diagnoses.

Conclusions:
The incidence of MDS for Manitoba is similar to published rates in Europe and the USA. This may be an underestimation of the actual incidence, as elderly patients may not undergo bone marrow examination if the therapeutic intervention is only supportive. Cancer registries that include MDS based on one-time bone marrow reports should include a review process of confirming or excluding the diagnosis of MDS based on follow up investigations and course of illness.

Disclosures:
No relevant conflicts of interest to declare.
Rapamycin-Induced Autophagy Generates Anti-Apoptotic Th1/Tc1 Cells That Mediate Increased Xenogeneic Gvhd.
Authors: Amarnath Shoba , Costanzo Carliann M , Foley Jason , Mariotti Jacopo , Konecki Daniel M , Gangopadhyay ANu , Eckhaus Michael , Wong Susan , Levine Bruce , June Carl H. , Fowler Daniel H. 
Published: October 2019

Abstract
Abstract 2456
Poster Board II-433
Murine T cells exposed to rapamycin maintain flexibility towards Th1/Tc1 differentiation; the degree to which rapamycin might inhibit human Th1/Tc1 differentiation has not been fully evaluated. In the presence of rapamycin, T cell co-stimulation and polarization with IL-12 or IFN-α permitted human CD4+ and CD8+ T cell differentiation towards a Th1/Tc1 phenotype: by intracellular flow, median percentage expression of Foxp3, IFN-γ, and T-bet was 4%, 20%, and 72%, respectively. Phospho-flow cytometry revealed that such Th1/Tc1 cells expressed activated STAT1 and STAT4 in spite of mTOR blockade; STAT activation was abrogated by PI3 kinase inhibition. Rapamycin-resistant human Th1/Tc1 cells (Th1/Tc1.R cells): (1) had increased expression of the autophagy-related gene LC3BII by gene array and protein analysis; (2) preferentially expressed anti-apoptotic bcl-2 family members (reduced Bax, Bak; increased phospho-Bad); (3) maintained mitochondrial membrane potentials; and (4) had reduced apoptosis relative to control Th1/Tc1 cells not generated in rapamycin (p=0.04). The anti-apoptotic phenotype of Th1/Tc1.R cells was abrogated by co-incubation with the autophagy inhibitor, 3-methyl adenine. The in vivo effect of the Th1/Tc1.R cells was evaluated using two xenogeneic GVHD (x-GVHD) models. First, in an LPS-induced x-GVHD model, Th1/Tc1.R cells resulted in lethality in 75% recipients; soluble TNF-α receptor therapy with etanercept reduced the frequency of lethality to 15%. Second, using a non-LPS natural history model of x-GVHD, recipients of Th1/Tc1.R cells (relative to recipients of control Th1/Tc1 cells) had increased human T cell engraftment (day 30 post-BMT, p=0.001), increased human T cell cytokine levels, increased human T cell expression of the cytotoxic degranulation molecule CD107 (p=0.05), and increased human T cell infiltration of skin, gut, and liver. In this model, lethality due to x-GVHD was also increased in Th1/Tc1.R cell recipients (lethality increased from 20% to 70%, p=0.04). We conclude that rapamycin therefore does not impair human T cell capacity for type I differentiation. Rather, by promoting autophagy rapamycin permits stable expression of T-bet and generates an anti-apoptotic Th1/Tc1 effector phenotype, thereby yielding increased x-GVHD.

Disclosures:
No relevant conflicts of interest to declare.
Cost-Utility Analysis of Von Willebrand Disease Screening in Adolescents with Menorrhagia.
Authors: Sidonio Robert F. , Smith Kenneth J , Ragni Margaret V. 
Published: October 2019

Abstract
Abstract 2476
Poster Board II-453

Introduction:
It is unknown whether it is cost effective to screen adolescents with menorrhagia for von Willebrand disease (VWD) prior to starting oral contraceptive pills (OCPs). Because OCPs can mask a diagnosis of VWD, a woman is at risk for potential future traumatic or surgical bleeding, once OCPs are stopped. We, therefore, designed a decision analysis model to evaluate the cost utility of VWD testing in adolescents with menorrhagia.

Methods:
A 20-year Markov decision analytic model was constructed to evaluate the cost-utility of two strategies: testing or not testing for VWD. The hypothetical patient is a 15-year-old female presenting with menorrhagia and a decision regarding VWD testing is made. The model includes probabilities of remaining well, suffering an acute menorrhagia bleeding event, surgical complications, OCP complications or dying. Probabilities, costs and utilities were estimated from published literature. The prevalence of type 1 VWD in adolescent females with menorrhagia was estimated to be 13%. We assumed all patients were treated with OCPs regardless of whether hemostatic testing was performed. All patients were assumed to have mild type I VWD, the most common subtype, and all were responsive to intravenous DDAVP. Probabilities of surgical complications in patients with and without VWD were based on adenotonsillectomy hemorrhage rates in children. The probability of acute menorrhagia bleeding necessitating hospitalization or red blood cell transfusion was estimated to be 1% in an adolescent with VWD and 0% in an adolescent with normal hemostatic testing. The sole complication from OCPs incorporated into this decision analytic model was acute deep vein thrombosis.

Results:
The cost of testing adolescents with menorrhagia for VWD was $1,638, vs. $1,251 for not testing for VWD. The effectiveness of not testing in quality-adjusted life-year (QALY) gained (14.237 QALY) was similar to the VWD testing strategy (14.246 QALY). Compared to not testing for VWD, screening for VWD had an incremental cost-effectiveness ratio (ICER) per QALY of $45,061/QALY, a value typically considered economically reasonable. In one-way sensitivity analysis, the outcome and ICER were most sensitive to the probabilities of an acute bleeding event, surgical complication, and the prevalence of VWD. Monte Carlo probabilistic sensitivity analysis, substituting input distributions rather than a single point estimate for the probabilities, costs and utilities, was also performed. Under this assumption, testing for VWD is a cost-effective strategy approximately 60% of the time when the cost-effectiveness threshold is $100,000/QALY.

Conclusions:
It is cost effective to perform VWD testing in adolescents presenting with menorrhagia prior to initiating OCPs. This is related to avoiding cost from postoperative and other bleeding when the diagnosis is masked by OCPs.

Disclosures:
No relevant conflicts of interest to declare.
Disparities of Common Hematological Malignancies in Asian Indian and Pakistani Population Living in the USA: A SEER Database Based Analysis From 1988 to 2006.
Authors: Hossain Akm , Rahman Rubayat , Abraham Jame 
Published: October 2019

Abstract
Abstract 2478
Poster Board II-455

Background:
It is estimated that Asian Indian and Pakistani (AIP) comprises about 1.5% of the total US population and is rapidly growing. Hematological malignancies account for about 15% of all the cancers diagnosed in this group. The aim of this study is to analyze epidemiologic and survival parameters of common hematological malignancies in AIP living in the USA and compare it to the US White (USW) population for the first time.

Methods:
The SEER (Surveillance Epidemiology and End results) database has been reporting cancer incidence since 1973. AIP with cancer diagnosis was reported separately under race and ethnicity in SEER database from 1988. Using SEER database 1988-2006, appropriate frequency and survival sessions (Kaplan-Meier survival method) were performed and epidemiologic characteristics for common hematological malignancies were compared between AIP and USW.

Results:

Conclusions:
Our analysis shows that AIP are diagnosed with common hematological malignancies at a younger age than USW. The distribution of these malignancies according to gender follows other major groups but there is no statistical difference in age at diagnosis, stages, tumor biology, treatment methodologies or survival between male and female AIP. Noticeable better 1-5 years survival could be attributed to difference in tumor biology, cytogenetics, emigrational factors, higher socioeconomic status, better access to health care, educational background with awareness and environmental factors. Future studies are warranted to examine the behavior and biology of tumor in this population.

Disclosures:
No relevant conflicts of interest to declare.