bluuebunny/crossref_metadata_2025_split huggingface dataset:
Apolipoprotein AIV (ApoA-IV) Is a Novel Ligand of Platelet β3 Integrin That Negatively Regulates Platelet Adhesion, Aggregation, and Thrombosis.
Authors: Spring Christopher M. , Jin Wuxun , Yang Hong , Reheman Adili , Zhu Guangheng , She Yimin , Cyr Terry , Tso Patrick , Davidson Sean , Freedman John , Ni Heyu 
Published: October 2019

Abstract
Abstract 156
Platelet adhesion and aggregation at sites of vascular injury are key events required for haemostasis and thrombosis. It has been documented that von Willebrand factor (VWF) and fibrinogen (Fg) are required for platelet adhesion and aggregation. However, we previously showed that occlusive thrombi still form in mice deficient for both Fg and VWF (Fg/VWF−/−) via a β3 integrin-dependent pathway. Here, we have investigated novel, non-classical ligands of β3 integrin that may regulate platelet adhesion and aggregation. To identify potential ligand(s) of β3 integrin, latex beads were coated with purified human platelet β3 integrin and incubated with human plasma. Protein(s) specifically associated with β3 integrin were electrophoresed and apolipoprotein AIV (ApoA-IV) was identified by mass spectrometry. We found that ApoA-IV binds to the surface of stimulated platelets, but not to quiescent platelets or β3−/− platelets, and ApoA-IV/platelet association was blocked by the addition of a specific anti-β3 integrin monoclonal antibody. It appears that ApoA-IV binds to, but is not internalized by platelet β3 integrins. ApoA-IV-deficient (ApoA-IV−/−) mice exhibited enhanced platelet aggregation induced by ADP, Collagen, and TRAP in plasma (but not PIPES buffer) compared to wild type (WT) littermates. This enhancement was diminished when ApoA-IV−/− plasma was replaced by WT plasma, indicating that the reduction was due to plasma ApoA-IV and not an unrelated platelet effect. When platelets were incubated with FITC-Fg, ApoA-IV was able to reduce platelet/Fg association, indicating that ApoA-IV may act to displace pro-thrombotic β3 integrin ligand(s). In support of this, ApoA-IV reduced the number of adherent platelets on immobilized Fg in perfusion chamber assays and enhanced thrombus formation was observed when ApoA-IV−/− mouse blood was perfused over collagen. We found that addition of recombinant ApoA-IV inhibited platelet aggregation and thrombus formation in vitro, while the control apolipoprotein ApoA-I did not. Using intravital microscopy, we further demonstrated that early platelet deposition was increased, and the time for thrombus formation and vessel occlusion were shorter in ApoA-IV−/− mice, which can be corrected by recombinant ApoA-IV transfusion. Furthermore, recombinant ApoA-IV inhibited WT platelet aggregation, thrombus formation and enhanced thrombus dissolution both in vitro and in vivo. Our data demonstrate for the first time that ApoA-IV is a novel ligand of platelet β3 integrin that negatively regulates thrombosis. These new data are consistent with the reported association between ApoA-IV and reduced cardiovascular diseases, and establish the first link between ApoA-IV and thrombosis.

Disclosures:
No relevant conflicts of interest to declare.
Low-Level FLT3-ITD Mutations Do Not Predict for Higher Relapse Rate in AML with Standard Risk Karyotpye.
Authors: Ward Richard , Kamel-Reid Suzanne , Xu Wei , Minden Mark D. , Schimmer Aaron D. , Yee Karen WL , Schuh Andre , Gupta Vikas , Brandwein Joseph 
Published: October 2019

Abstract
Abstract 1591
Poster Board I-617
High-level FLT3-ITD mutations predict for a higher relapse rate and inferior survival among patients with standard risk karyotype AML. The influence of low-level FLT3-ITD mutations is less clear, although the MRC group (Gale et al, 2008) reported that low-level mutations are associated with an inferior prognosis as compared to an unmutated group. In the absence of FLT3-ITD, NPM1 mutations predict for a lower relapse rate. We analyzed outcomes of intensive chemotherapy in patients with standard risk karyotype AML (n=131) between 2004-2008. Patients received uniform induction chemotherapy consisting of cytarabine plus daunorubicin (7+3), followed by 2 consolidations consisting of high-dose cytarabine plus daunorubicin for pts under age 60 (n=96) or 7+3 followed by NOVE for pts age 60+ (n=35). Patients were divided into 3 groups based on the ratio of FLT3-ITD:FLT3-wt: There were 73 patients with negative FLT3-ITD (defined as FLT3-ITD:wt ratio < 0.01), 30 patients with low-level ITD (ratio > 0.01 – 0.37), and 28 patients with high-level ITD (ratio > 0.37). The mean presenting WBC was 32.2 ×109/L in the group with negative ITD, 49.4 ×109/L in the group with low-level ITD and 97.2 ×109/L in the group with high-level ITD (p < 0.0001). At a median follow-up of 19 months (range 2-95 months), the median OS of the entire group was 21.3 months. Patients with high-level ITD had a significantly inferior RFS (p = 0.0009) and OS (p = 0.003) as compared to the low-level and negative groups. Comparing the negative ITD and low-level ITD groups, there was no significant difference in RFS (p = 0.65) or OS (p = 0.18). The frequency of NPM1 mutations was not significantly different between these two groups (42% vs. 35%). These data were re-analyzed using a different cutoff according to % FLT-ITD positivity: negative < 1% (n=73), low-level 1 – 50% (n=42), high level > 50% (n=16). Using these ranges, the low-level FLT3-ITD group had a significantly lower CR rate (74% vs. 93%, p = 0.004) and OS (36% vs. 61%, p = 0.01) as compared to the group with negative FLT3-ITD, but there was no significant difference between these two groups with respect to RFS (2 year RFS 48% in low-level ITD group vs. 40% in negative ITD group). The high-level ITD group demonstrated significantly inferior RFS (p = 0.02) and OS (p = 0.01) as compared to the other two groups. These findings confirm the poor prognosis associated with high-level FLT3-ITD mutations due to high relapse rates. However, in contrast to previously reported data, we did not find that low level FLT3 –ITD mutations were associated with inferior RFS, although we did find, unexpectedly, that this low-level group had a lower CR rate.

Disclosures
No relevant conflicts of interest to declare.
Chemokines in Leukemic Infiltration of the Central Nervous System in Childhood Acute Lymphoblastic Leukemia.
Authors: Ramirez Manuel , Gomez Ana M , Martinez Carolina , Lassaletta Alvaro , Fuster Jose L , Esquembre Carlos , Guibelalde Mercedes , Pedro Gomez , Calvo Carlota , Molina Javier , Vivanco Jose L , de Toledo Jose Sanchez , Bureo Encarna , Madero Luis 
Published: October 2019

Abstract
Abstract 1627
Poster Board I-653

Background
Leukemic blasts from B-cell acute lymphoblastic leukemia (B-ALL) and T-ALL circulate through the blood stream and may infiltrate different organs. Extramedullary organs may act as sanctuaries for lymphoblasts, preventing the exposure to adequate levels of chemotherapeutic drugs. Typical extramedullary relapses are seen in testes and in central nervous system (CNS). We aimed at determining whether chemokines may play a role in the infiltration of the CNS by leukemic blasts in childhood ALL. We studied the expression of chemokine receptors in ALL blasts in marrow, as well as the levels of chemokine ligands in the cerebrospinal fluid (CSF) of children with B- or T-ALL. If chemokines had a role in CNS leukemic infiltration, the following should be confirmed: leukemic blasts should express high levels of the chemokine receptor/s for which high levels of its corresponding ligand/s were detected at the CNS.

Methods
This prospective study was approved by the local ethical committees for clinical research. Samples from 80 children in 10 Spanish pediatric oncology units were obtained. We detected the presence of leukemic blasts in CFS by flow cytometry. We defined leukemic infiltration of CFS samples as the presence of cells with the same immunophenotype as the leukemia in the marrow aspirates. We detected the expression levels of 9 CCR and 6 CXCR molecules in ALL blasts by flow cytometry in marrow aspirates. Levels of chemokine ligands were quantitated by Cytometric Bead Array or by commercial ELISA kits in CSF samples.

Results
We found that chemokine receptors expression and levels of chemokine ligands varied depending upon the lineage (T versus B), the maturation state (pre-T versus T; pro-B versus pre-B versus common-B) and the risk-status (high versus non-high) of the leukemia. T-ALL patients with high levels of CNS leukemic infiltration expressed significantly higher levels of CXCL10 compared to the same parameters of T-ALL patients with low/absent levels of CNS disease (p=0,049). Common B-ALL patients with high levels of CNS leukemic infiltration expressed higher levels of CCL22 compared to that of common B-ALL patients with low/absent levels of CNS disease (p=0,059). Among the 4 patients with a CNS relapse, we detected higher levels of CXCR3 (p=0,0038) and of its ligand, CXCL10 (p=0,0169), compared to patients who did not relapse.

Conclusions
Our study suggests that the CXCR3/CXCL10 axis may be involved in the CNS relapse of high-risk ALL in children: high expression of CXCR3 on marrow blasts plus high levels of CXCL10 in the CNS was associated with leukemic CNS relapse.

Disclosures
No relevant conflicts of interest to declare.
Heightened Susceptibility to Influenza Mortality in Immunodeficient Mice Caused by a T-Cell Specific Defect in SOD2.
Authors: Case Adam John , Mcgill Jodi L. , Sangster Stephen C. , Madsen Joshua M. , Tygrett Lorraine T. , Johns Anna G. , Takahashi Takamune , Shirasawa Takuji , Spitz Douglas R. , Meyerholz David K. , Waldschmidt Thomas J , Legge Kevin L , Domann Frederick E. 
Published: October 2019

Abstract
Abstract 1655
Poster Board I-681
The role of SOD2 in development and function of the immune system remains unknown. Due to the early lethality of constitutive SOD2 knock-out mice, we recently reported the creation of T-cell specific SOD2 conditional knock-out mice to identify an immunological role, if any, for MnSOD in a viable organism. Knock-out mice displayed decreases in T-cell numbers (∼2-5 fold) within all lymphoid organs assayed (i.e. thymus, spleen, lymph nodes, and peripheral blood). Quantitative morphometry on transmission electron micrographs of SOD2 knock-out thymocytes indicated defects in mitochondrial morphology compared to controls. Further analysis of T-cell subpopulations by flow cytometry revealed that áβ T-cells had the largest decrease in number (CD4-,CD8+ affected more than CD4+,CD8-), while the γd T-cell population appeared unaffected or increased. The SOD2 knock-out T-cells demonstrated a more sizable activated population (CD44+, CD62L-) than the controls (∼2 fold for both CD4-,CD8+ and CD4+,CD8-), and mRNA expression microarray analysis showed up-regulation of numerous genes involved in T-cell activation. To query immune system function in the mice with SOD2-/- T-cells, we challenged the knock-out mice with influenza A virus (IAV). Upon infection, the knockout animals suffered from increased morbidity (i.e. weight loss) and 100% succumbed to infection within 11 days, whereas all control animals made a full recovery despite initial morbidity. Characterization of T-cell response to IAV in the knock-outs revealed limited T-cell migration to the lungs (∼2-fold fewer), smaller IAV-specific tetramer-positive populations, and attenuation of interferon gamma (INFγ) production. Taken together, these results indicate that MnSOD is critical for proper immune system development and function. Future studies will examine the mechanism of the decrease in T-cell numbers as well testing pharmaceutical SOD mimetics that may demonstrate a rescue of the observed phenotype. This work was supported by NIH grants CA73612 and CA115438.

Disclosures
No relevant conflicts of interest to declare.
Targeting Bcl-2 Family Proteins in Adult T-Cell Leukemia/Lymphoma: In Vitro and In Vivo Effects of a Novel Bcl-2 Family Inhibitor ABT-737.
Authors: Ishitsuka Kenji , Ishikawa Chie , Yotsumoto Fusanori , Katsuya Hiroo , Kunami Naoko , Sawada Shigeki , Tanji Hiroe , Takeshita Morishige , Miyamoto Shingo , Mori Naoki , Tamura Kazuo 
Published: October 2019

Abstract
Abstract 1685
Poster Board I-711
Adult T-cell lymphoma/leukemia (ATLL) is a T-cell malignancy caused by human T-lymphotrophic virus type I (HTLV-I), and its therapeutic outcome is still remains very poor. Therefore, novel therapeutic strategies are needed to improve patient outcome. In this study, we elucidated the therapeutic potential to target anti-apoptotic Bcl-2 family proteins for the treatment of ATLL by using ABT-737 (Abbott Laboratories, Abbott Park, IL, USA), a small molecule inhibitor of Bcl-2, Bcl-XL and Bcl-w. We first validated the rationale of this study by assessing the expression of Bcl-2 family proteins among 25 lymph-node specimens derived from ATLL patients by using immunohistochemistory. Both or either of Bcl-2 and Bcl-XL proteins was highly expressed in 80% of specimens. We next examined the cytotoxicity of ABT-737 against ATLL cell lines. ABT-737 significantly inhibited growth of MT-1, MT-2 and HuT 102 cells with a concentration of 50 percent inhibition (IC50) at 72 h of 2.4, 0.23 and 0.008μM, respectively. We then elucidated the mechanism of growth inhibition induced by ABT-737 using MT-1 and MT-2 cells. ABT-737 induced apoptosis in MT-1, MT-2 cells with cleavage of caspase 9, 3 and PARP. ABT-737 also induced apoptosis in fresh tumor cells derived from patients with ATLL. We next elucidated the potential of ABT-737 to enhance the cytotoxicity induced by conventional chemotherapeutic agents. The interaction between them was evaluated using the Chou-Talalay method by determining the combination index. ABT-737 synergistically enhanced the cytotoxicity and apoptosis induced by either of doxorubicin, vincristine or etoposide, which is a current key drug to treat ATLL. Most importantly, ABT-737 significantly inhibited tumor growth of in vivo ATLL model using SCID mice inoculated by HuT 102 cells subcutaneously. The mean tumor volume, weight and serum level of soluble interleukin-2 receptor á of ABT-737 (100mg/kg/day)-treated mice were significantly lower than those of vehicle-treated mice after treatment for 21 days. Moreover, massive induction of apoptosis in tumors treated by ABT-737 was observed by immunofluorescent TUNEL assay. These results suggest that ABT-737 used either alone or in combination with conventional cytotoxic drugs, represents a promising novel targeted approach to overcome drug resistance and improve patient outcome in ATLL.

Disclosures
No relevant conflicts of interest to declare.
Adoptive Therapy for Lymphoma with CD4 Memory T Cells Depleted of CD137-Expressing Tregs.
Authors: Goldstein Matthew J , Houot Roch , Kohrt Holbrook E , Brody Joshua , Levy Ronald 
Published: October 2019

Abstract
Abstract 1693
Poster Board I-719
A central goal of cancer immunotherapy is an adaptive immune response against tumors. The memory T cell is a critical mediator of this response as it can give rise to effector cells as well as self-renew. Regulatory T cells (Tregs) present a barrier to effective cancer immunotherapy. Indeed, cancer patients have increased numbers of CD4+CD25+ Tregs and cancer vaccination strategies in some cases expand this cell population. Here, we demonstrate that (1) CD4+CD44hi memory T cells are effective in mediating anti-tumor immunity and (2) that expression of CD137 can be used to exclude tumor-reactive Tregs from the CD4+CD44hi population.
We have established a model for adoptive therapy of mantle cell lymphoma in which CD4 T cells mediate anti-tumor immunity. Specifically, we use a whole tumor-cell vaccine to induce anti-tumor immune cells in vivo. These cells are isolated and adoptively transferred into lethally irradiated, syngeneic, recipient mice. We show that CD4 but not CD8 T cells from vaccinated donor mice can prevent tumor growth when adoptively transferred into irradiated recipient mice.
We observed that a majority of anti-tumor T cells display a memory phenotype. 10 days after transfer, T cells from recipient mice were co-cultured with irradiated lymphoma cells for 24 hours. Only CD4 T cells produced IFN-γ in response to co-culture and greater than 95% of IFN-γ+ CD4 T cells expressed the memory marker CD44. Finally, we observed that transferred CD4+CD44hi T cells persisted for over 100 days suggesting that this CD4 subset is important for lasting anti-tumor immunity.
Contaminating Tregs may limit the effectiveness of our CD4 T cell adoptive therapy. In order to functionally deplete these Tregs from the CD4 population, we sought to identify a surface marker that could uniquely distinguish tumor-reactive Tregs from other CD4 T cells. T cells from vaccinated donor mice were co-cultured with irradiated lymphoma cells for 24 hours. We evaluated a panel of activation markers and observed that CD137 expression defined a distinct population of Tregs. Based on these results, we used flow cytometry to isolate a sub-population of CD4+CD44hiCD137- T cells from vaccinated donor mice. Adoptive transfer of less than 100,000 CD44hiCD137- but not other sub-populations of CD4 T cells provided significant protection from tumor challenge. These results suggest that CD137 defines a novel population of tumor-reactive Tregs. This marker can facilitate the enrichment of anti-tumor CD4 memory T cells within the CD44hiCD137- population.
In conclusion, these findings highlight the potential use of CD4 T cells in adoptive therapy for mantle cell lymphoma.

Disclosures
No relevant conflicts of interest to declare.
The CXCR4 Antagonist AMD3100 Has Dual Effects, Initially Enhancing and Later Inhibiting Survival and Proliferation, in Myeloid Leukemia Cells in Vitro.
Authors: Kim Ha-Yon , Hwang Ji-Young , Kim Seong-Woo , Yun Gak-Won , Yang Young-Joon , Lee Hyo-Jin , Jo Deog-Yeon 
Published: October 2019

Abstract
Abstract 1721
Poster Board I-747
AMD3100, a small bicyclam antagonist for chemokine receptor CXCR4, induces the peripheral mobilization of hematopoietic stem cells. It also induces the segregation of leukemia cells in the bone marrow microenvironment, which should enhance the chemosensitivity of the cells. Based on these observations, AMD3100 is being considered for clinical use. However, AMD3100 activates G-protein coupled with CXCR4 and acts as a partial CXCR4 agonist. In this study, we explored whether AMD3100 affects the proliferation and survival of myeloid leukemia cells. As demonstrated previously, both AMD3100 and T140, another CXCR4 antagonist, markedly inhibited stromal cell-derived factor-1 (SDF-1)-induced chemotaxis and induced the internalization of CXCR4 in myeloid leukemia cell lines (U937, HL-60, MO7e, KG1a, and K562 cells) and CD34+ primary human acute myeloid leukemia (AML) cells. SDF-1 alone did not stimulate the proliferation of these leukemia cells, nor did it rescue the cells from apoptosis induced by serum deprivation. By contrast, AMD3100, but not T140, stimulated the proliferation of all five leukemia cell lines and primary AML cells in a dose-dependent manner in serum-free conditions for up to 5 days (∼ 2-fold increases at a concentration of 10-5M), which was abrogated by pretreating the cells with pertussis toxin. AMD3100 binds to CXCR7, another SDF-1 receptor, and all of the cells examined in this study expressed CXCR4 on the cell surface to some extent. The proliferation-enhancing effects of AMD3100 were not changed by knocking-down CXCR7 using the siRNA technique, whereas knocking-down CXCR4 significantly delayed the enhanced proliferation induced by AMD3100. Neither AMD3100 nor T140 induced the phosphorylation of Akt, Stat3, MAPK p44/p42, or MAPK p38, which are involved in SDF-1 signaling. In extended cultures of these cells for up to 14 days, AMD3100, but not T140, induced a marked decrease in the number of cells, compared to the control, after incubation for 5-7 days. Adding SDF-1 at the beginning and middle of the incubation did not affect the early increase or later decrease in the number of cells. AMD3100 reduced the apoptosis of these cells to a modest degree over the first 5-7 days and then markedly increased it. Consistent with the proliferation assay, AMD3100 increased the number of leukemia cell colonies during the early period of the assay, while it markedly decreased the number and size of the colonies in the later period of the assay. In conclusion, AMD3100 exerts dual effects, initially enhancing and subsequently inhibiting the survival and proliferation, in myeloid leukemia cells in vitro.

Disclosures
No relevant conflicts of interest to declare.
The Influence of Polymorphisms of Interleukin-17F Genes On the Susceptibility and Clinical Outcome of Multiple Myeloma.
Authors: Saitoh Takayuki , Kasamatsu Tetsuhiro , Yokohama Akihiko , Handa Hiroshi , Tsukamoto Norifumi , Karasawa Masamitsu , Ogawara Hatsue , Nojima Yoshihisa , Murakami Hirokazu 
Published: October 2019

Abstract
Abstract 1784
Poster Board I-810

Introduction
Recent several cytokine studies have shown dysfunctional T cell responses in multiple myeloma (MM) patients. Regulatory T (Treg) cells, is essential for dominant immunologic tolerance. This decreased number and function of Treg cells in MM has been reported, leading to dysfunctional T cell responses. Interleukin-17 F(IL-17F) is a relatively new cytokine that regulates the adaptive and innate immune systems. In vivo studies in murine disease indicate that the Th17 lineage plays a pathogenic role in autoimmune disease. IL-17 polymorphism has been implicated in autoimmunity, including ulcerative colitis and asthma. Polymorphisms were studied, including the coding-region sequence variant single nucleotide polymorphism rs763780 (7488T/C), which causes a His-to-Arg substitution at amino acid 161 (H161R). We examined the single nucleotide polymorphisms (SNPs) in the promoter regions of the IL-17 genes in patients with MM, and analyzed the relationship between IL-17 SNPs and clinical features.

Methods
Eighty one patients with MM [age range, 40-83 years; stage I (n=9), stage II (n=21), stage III (n=51); IgA(n=13), IgG(n=48), IgD(n=1), non-secretary (n=3), Bence Jones(n=16)] and 100 healthy controls were included. Genomic DNA was isolated from peripheral blood using the DNA Kit (QIAGEN, Hilden, Germany). Genotyping in IL-17F was determined by PCR based technique. Genotype and allele frequencies were compared between the study groups using χ2-test. The characteristics and laboratory features of the MM patients with each IL-10 promoter polymorphism were compared using χ2-tests and student t-tests. Probability values <0.05 were considered statistically significant.

Results
The frequencies of the genotypes in MM patinets were as follows: TT (76%), TC (18%), and CC (6%). Patients with MM had a higher frequency of The IL-17F CC genotype compared with healthy controls (P<0.05). No significant difference in the clinical presentation at diagnosis was indicated according to IL-17 polymorphism considering sex, Ig type, Durie-Salmon staging system, and international staging system.

Conclusion
Homozygosity of the H161R variant was associated with susceptibility of MM. These observations suggest that IL-17 may affect dysfunctional T cell responses in MM.

Disclosures
No relevant conflicts of interest to declare.