bluuebunny/crossref_metadata_2025_split huggingface dataset:
BTG1 Controls Glucocorticoid Sensitivity in Acute Lymphoblastic Leukemia by Regulating Nuclear Receptor-Mediated Transcription.
Authors: van Galen Joost C. , Kuiper Roland P. , van Emst Liesbeth , Levers Marloes R. , van Reijmersdal Simon V. , van Kessel Ad Geurts , Hoogerbrugge Peter M. , van Leeuwen Frank N. 
Published: April 2020

Abstract
Glucocorticoids (GCs) are global regulators of gene transcription that act by binding to the glucocorticoid receptor, a ligand-activated transcription factor belonging to the nuclear receptor family. As synthetic GCs such as prednisolone or dexamethasone specifically induce cell cycle arrest and apoptosis in lymphoid cells, these drugs are widely used in the treatment of (childhood) acute lymphoblastic leukemia (ALL). GC resistance is a strong independent predictor of poor prognosis in the treatment of childhood ALL, but the underlying mechanisms remain poorly understood. In a previous study (Kuiper et al. Leukemia 2007) we determined by array-based SNP analysis that microdeletions affecting the anti-proliferative gene B-cell translocation gene 1 (BTG1) occurred in 4 out of 33 pre-B ALL cases. In our current study we show that prednisolone causes a 3-fold induction of BTG1 mRNA expression both in pre-B ALL cell lines and primary ALL, implicating BTG1 in cellular responses to GCs. Moreover, RNA-interference-mediated knockdown of BTG1 renders RS4;11 pre-B leukemia cells refractory to prednisolone-induced apoptosis. We show by genome-wide mRNA profiling that loss of BTG1 completely abrogates prednisolone-induced gene expression by downregulation of the glucocorticoid receptor NR3C1. Moreover, we present evidence showing that BTG1 is part of a nuclear receptor complex that regulates expression of NR3C1 and consequently GC responsiveness in ALL. In conclusion, we have identified BTG1 as an important determinant of GC sensitivity in ALL.
Novel Pleiotropic Effects of Thrombin in Regulation of the Metastatic Potential of Human Rhabdomyosarcoma (RMS) Cells.
Authors: Wysoczynski Marcin , Ratajczak Mariusz Z 
Published: April 2020

Abstract
Rhabdomyosarcoma (RMS) is the most common soft-tissue sarcoma of adolescents and children that frequently infiltrates bone marrow (BM). We identified chemokines and growth factors [i.e., stromal derived factor (SDF)-1, hepatocyte growth factor (HGF)] that play important roles in RMS metastasis (Blood2002;100:2597, Cancer Res.2003;63:7926,Cancer Res.2007;67:2131). However, novel evidence indicates that the metastatic process for many tumors may be modulated by components of the coagulation cascade (e.g., thrombin, activated platelets). Thus, we became interested in the role of coagulation cascade in modulating metastasis of RMS cells. We learned that RMS cells express tissue factor (TF) and thus may activate coagulation by generating thrombin. Thrombin activated in the tumor microenvironment activates platelets that release microvesicles. These interact with RMS cells and/or directly stimulate PAR 1–4 receptors that are expressed on RMS cells. Focusing on these effects, 9 human RMS cells lines were employed for our studies. We learned that platelet-derived microvesicles (PMVs) transfer several platelet integrin receptors to RMS cells (e.g., a2b3) that are important for interaction with the endothelium, thus increasing their adhesive potential to endothelial cells, fibronectin, and fibrinogen. More importantly, RMS cells covered with PMVs showed higher metastatic potential after intravenous injection into severe combined immunodeficient (SCID) mice. This could be explained by enhanced adhesiveness of PMV-covered RMS cells to endothelial cells in small vessels. On the other hand, PMVs also directly chemoattracted RMS cells and activated MAPKp42/44 and AKT. Since we found that RMS cell lines express functional PAR 1–4 receptors, we become interested in the thromin-mediated responses of these cells. In RMS, we observed cells stimulated by thrombin phosphorylation of MAPKp42/44 and p38, but not AKT. However, we did not observe any effect from thrombin on proliferation and survival of RMS cells. To our surprise, thrombin decreased RMS chemotactic responses to SDF-1, HGF, and PMVs. Thrombin also decreased adhesion of RMS cells to fibronectin and laminin. In conclusion, we demonstrate for first time that RMS-expressed TF activates prothrombin and that thrombin is a novel, underappreciated, pro-metastatic factor for these cells. Activated in tumor proximity by thrombin, platelets release PMVs that chemoattract and transfer several platelet-derived receptors/adhesion molecules to RMS cells that are crucial for adhesion/interaction with the endothelium. Conversely, by decreasing the responsiveness of RMS cells to local chemoattractants and decreasing adhesiveness of RMS cells, thrombin promotes their release from the primary tumor into circulation. Consequently, RMS cells that are covered by PMVs release into circulation and respond to chemoattractants in distant organs for metastasis.
Monitoring of ADAMTS13 in Patients with Thrombotic Thrombocytopenic Purpura: Prediction of Response to Therapy, Risk of Relapse, and Long- Term Outcome.
Authors: Knoebl Paul , Koder Silvia , Schellongowski Peter , Distelmaier Peter , Quehenberger Peter , Pabinger Ingrid , Jilma Bernd 
Published: April 2020

Abstract
A severely reduced ADAMTS13 activity due to inhibitory autoantibodies is a key feature of acquired thrombotic thrombocytopenic purpura (TTP), leading to the persistence of ultralarge VWF multimers, platelet aggregation and disturbance of microcirculation.
We followed 39 patients (8 male, 31 female, mean age 38 years) with clinical signs of TTP over a period between 5 days to 16 years and observed a total of 53 episodes of TTP. ADAMTS13 was measured with a collagen-binding assay and the FRETS-VWF73 based Technozym ADAMTS-13 assay (activity and antigen, respectively). ADAMTS13 inhibitor was measured with a modified Bethesda method with both the above mentioned assays, and with the Technozym ADAMTS-13 INH ELISA.
Thirty-one patients had autoimmune TTP, and 47 episodes of TTP were analyzed in these patients. In all acute episodes, ADAMTS13 activity was below the detection limit (&lt;0.05 U/ml), but ADAMTS13:Ag levels were below 0.1 U/ml only in 55% of the episodes. Anti-ADAMTS13 antibodies were detected in all episodes. Treatment consisted of plasma exchange (89% of the episodes), immunoadsorption (6%), steroids (70%), rituximab (15%), splenectomy (11%), aspirin (74%). Median time to platelet count normalization was 20 days (range 4–91 days), not related to the ADAMTS13-inhibitor titer. Platelet counts, LDH levels, and reticulocyte counts were better predictors of treatment response. Plasma exchange did not directly influence ADAMTS13 levels or clear the inhibitors. Three patients died during the first episode (myocardial infarction), one in 2nd relapse. ADAMTS13 activity increased &gt;0.2 U/ml in 66% of the episodes (after median 160 days). In the remaining cases anti-ADAMTS13 antibodies persisted during remissions for up to 2 years. In 3 cases the antibody reoccurred after initial normalization of ADAMTS13 activity, and clinical relapses followed. In total, 21 relapses were observed after a median of 46 months (range 1– 87), all associated with low ADAMTS13 levels. Rituximab was given in 7 cases of relapsing TTP and resulted in complete, durable clearance of the antibodies in 100%.
Determination of ADAMTS13-related parameters is useful to distinguish between autoimmune, hereditary, and secondary forms of TTP and to choose an appropriate therapy. It is also useful to predict the risk of relapse in patients with TTP in remission.
In Vitro Efficacy of Recombinant ADAMTS13 in Acquired TTP Patients with Anti-ADAMTS13 Inhibitory Antibody.
Authors: Plaimauer Barbara , Juno Claudia , Scheiflinger Friedrich 
Published: April 2020

Abstract
Thrombotic thrombocytopenic purpura (TTP) is associated with a severe functional deficiency of the ADAMTS13 metalloprotease resulting in accumulation of highly adhesive ultra-large von Willebrand factor (ULVWF) multimers. ULVWF promote spontaneous platelet clumping eventually leading to life-threatening widespread microvascular thrombosis in multiple organs. Inhibitory and non-inhibitory anti-ADAMTS13 autoantibodies that result in functional deficiency and/or accelerated in vivo clearance of ADAMTS13 have been detected in patients suffering from acquired idiopathic TTP. Current treatment with plasma exchange therapy is considered to remove the autoantibodies and to replenish plasma with the deficient protease. While researching therapeutic recombinant ADAMST13 (rADAMTS13) as a possible treatment modality for TTP patients, we investigated the in vitro potency of rADAMTS13 to overwhelm and neutralize circulating anti-ADAMTS13 antibodies and concurrently to reinstate plasma ADAMTS13 to normal. Mixing and incubating patient plasma with normal reagent plasma and subsequent FRETSVWF73 activity analysis was used to calculate the individual anti-ADAMTS13 inhibitor titers in 36 untreated idiopathic TTP patient plasma samples with severe ADAMTS13 deficiency (&lt;10% of normal). The inhibitor titers (IU/ml) ranged from 1.5 to 85IU/ml (median of 3.75 IU/ml). To compare the performance of the different patient samples at equal inhibitor titers, we diluted each sample to predefined inhibitor titers (e.g. in patient samples with inhibitor titers &lt;10IU/ml we diluted to 1, 3, 6 and 9IU/ml). Then, incrementally increasing concentrations of purified rADAMTS13 derived from stably transfected CHO cells were added to each pre-set inhibitor titer done for each of the 36 patient samples. Complex formation of rADAMTS13 and anti-ADAMTS13 patient antibody was allowed and the remaining ADAMTS13 activity was analyzed. The input of rADAMTS13 required to saturate circulating inhibitors and to elevate the activity level up to 1U/ml in the plasma was calculated by regression analysis. Our data indicate a linear correlation between supplemented rADAMTS13 and anti-ADAMTS13 antibody titer (for titers &lt;10IU/ml) suggesting that rADAMTS13 should be further investigated as a possible treatment of acquired TTP.
Autologous Peripheral Blood Stem Cell Products from Patients with Hematologic Malignancies Have Increased Frequency of Regulatory T Cells (CD4+FoxP3+ Treg).
Authors: Kao Grace , Stevenson Kristen , Kim Elliot , Spanjaard Elena , Kim Haesook T , Ritz Jerome 
Published: April 2020

Abstract
Increased numbers of regulatory T cells (Treg) with immune suppressive function have been observed in patients with hematological malignancies. Many of these patients will undergo stem cell mobilization with high dose cyclophosphamide and G-CSF to prepare for autologous stem cell transplantation. Although infusion of low dose cyclophosphamide (Cy) seems to reduce the number of circulating Tregs, mobilization with high dose Cy and G-CSF was shown to increase the frequency of immunosuppresive Treg in stem cell autografts of myeloma patients. Treg populations have been defined by different phenotypic criteria, including CD4+FoxP3+ and CD4+CD25+ CD127lo. In this study, we compare the impact of donor types and stem cell mobilization regimens on CD4+FoxP3+ and CD4+CD25+ CD127lo Treg frequencies in 63 apheresis products.
Methods: Apheresis products from 23 healthy donors (17 donors received G-CSF and 6 had no stem cell mobilization) and 40 patients with hematological malignancies (1 AML, 2 HD, 25 NHL, 10 MM, 2 neuroblastoma) were evaluated. Patients with malignancies were mobilized with chemotherapy (5 RICE, 25 Cy, 1 Ara-c+Etoposide) + G-CSF (N=31), AMD3100 + G-CSF (N=5), or G-CSF alone (N=2). Samples from each product were incubated with fluorochrome-conjugated antibodies against cell surface makers, CD45, CD4, CD14, CD127, and CD25, followed by intracellular staining with anti-FoxP3 antibody. Six-color flow cytometry and sequential gating was performed for each sample to determine the frequency of CD4+Foxp3+ and CD4+CD25+CD127lo Treg population.
Results: A strong correlation was found between CD4+Foxp3+ and CD4+CD25+CD127lo Treg subsets (r=0.67, p&lt;0.001).The percentage of both Treg populations was not different between mobilized or non-mobilized products from healthy donors (p=0.94) or between NHL and MM patients (p=0.81). Higher CD4+FoxP3+ Treg frequency was observed in autologous grafts from patients compared to healthy donors (p&lt;0.001). The median CD4+FoxP3+ Treg frequency among mobilized products from patients and healthy donors were 8.5% (range, 1.8–38.9) and 4.3% (range, 1.8–15.0), respectively. Autografts from patients who received AMD3100+G-CSF compared to those who received chemotherapy + G-CSF also revealed higher CD4+FoxP3+ Treg content (median 11.3 vs. 7.5, p=0.04). Similar analysis using CD4+CD25+CD127lo Treg subset did not demonstrate any statistical significance.
Conclusions: Although correlation was observed between CD4+FoxP3+ and CD4+CD25+CD127lo subsets, CD4+FoxP3+ is a more sensitive marker for the Treg population in stem cell products. Higher CD4+FoxP3+ Treg frequency was observed in grafts from patients with hematological malignancies compared to healthy donors. The addition of a novel mobilization agent, AMD3100, to Cy mobilization may further increase the Treg content of autologous stem cell products.
Compared to Adult Peripheral Blood T Cells, Cord Blood T Cells Show Enhanced Immunological Recognition of Chronic Lymphocytic Leukemia Tumor Cells.
Authors: Ramsay Alan G. , Xing Dong-Xia , Decker William K. , Burks Jared K. , Wierda William G. , Gribben John G. , Shpall Elizabeth J. 
Published: April 2020

Abstract
Following allogeneic stem cell transplantation (SCT) and donor lymphocyte infusion (DLI) from adult peripheral blood (APB), chronic lymphocytic leukemia (CLL) cells are good targets of a graft-versus-leukemia effect. However, some patients eligible for this treatment do not have a suitable allogeneic donor and CLL B cells have been shown to be dysfunctional antigen-presenting cells (APCs) for allogeneic APB T cells. As a result, allogeneic APB T cells show suppressed immunological synapse formation with CLL cells. Umbilical cord blood (CB) is a promising source of hematopoietic cells for allogeneic transplantation and can be obtained from matched unrelated donors with greater tolerance for incompletely HLA-matched recipients. Moreover, we have successfully expanded CB T cells ex vivo (anti-CD3/CD28 beads and rIL-2) using a protocol that retains a naïve and diverse immune population including central memory cells. In this present study we used confocal microscopy to visualize F-actin polymerization to assess immunological synapse formation of CB T cells compared to APB T cells with CLL B cells with and without superantigen as APCs. Our results identify the ability of unexpanded and expanded CB CD4 and CD8 T cells to form F-actin immune synapses with CLL B cells and of note, CB was more effective than unexpanded or expanded APB T cells (p&lt;0.05). Of interest, the expansion protocol maintained immune synapse formation with a trend towards increased F-actin polymerization. As control, we examined the ability of unexpanded and expanded T cells to form F-actin synapses with allogeneic healthy B cells with or without superantigen as APCs and found no significant difference between CB and APB as a source of T cells. Our results demonstrate that CB T cells have an enhanced ability to recognize CLL B cells as allogeneic APCs compared to APB T cells and provide important and exciting pre-clinical data for the potential use of expanded CB T cells in the setting of CB transplantation in CLL.
In Vivo Development of Murine NK Cells Early after Congeneic BMT: Effects of MHC Molecules, and the Administration of hIL-15.
Authors: Barao-Silvestre Isabel , Redelman Doug , Ames Erik , Weiss Jonathan , Sun Kai , Welniak Lisbeth , Ortaldo John , Wiltrout Robert , Murphy William 
Published: April 2020

Abstract
Natural Killer (NK) cells are lymphocytes of the innate immune system that are able to kill a variety of tumors and pathogen-infected cells without prior sensitization. NK cells are the first lymphoid cells to repopulate following bone marrow transplantation (BMT). The present study shows that murine NK cells developing in vivo after BMT are phenotypically and functionally distinguishable from mature adult NK cells. Using a congeneic BMT mouse model (CD45.1/H-2b → C57BL/6, CD45.2/H-2b) we demonstrated here that donor derived BM-NK progenitors (CD122+NK1.1-CD3-)were present in the BM and periphery (spleen), at day 14 after BMT, and developed into NK cells expressing high levels of CD122, NKG2D, CD94, DX5 and CD43. However, surface expression of Ly49 inhibitory receptors was altered with Ly49C/I being under-expressed (9.8 %± 3.2 %), and Ly49G2 being highly expressed (62 %± 3.1 %) when compared to NK cells from non-transplanted adult mice (Ly49C/I, 43.1 %± 7.6 % and Ly49G2, 44.3 %± 13.5 %). At 28 days after BMT, there was a normalization with regard to Ly49 phenotype. The developing NK cells manifested functional deficits compared to non-transplanted adult NK, even when stimulated in vitro with Interleukin (IL)-2, as evidenced by decreased interferongamma (IFN-g) production and cytolytic activity. In order to examine the effects of major histocompatibility complex (MHC) molecules on NK development independently of allelic variation of Ly49s, we performed syngeneic BMT using B10D2 mice (H-2d). We observed the same pattern of Ly49s expression during NK development demonstrating that the acquisition of these receptors early after BMT is not determined by the MHC haplotype. Because IL-15 plays a crucial role in NK cell development, we administrated human (h) IL-15, via hydrodynamic injection of the respective gene, at day 11 after BMT, to accelerate NK maturation. This method resulted in a high but transient production of hIL-15 (736 ± 41 pg/ml) in the serum for up to 2 weeks. A subsequent but temporary increase in the numbers of donor derived NK cells (3 fold) occurred within 72 hours, in both BM and periphery, following hIL-15 gene delivery. Despite these augmenting effects, the developing NK cells still exhibited poor functionality compared to non-transplanted adult mice. These studies describe the possibility of NK development in the spleen, and indicate that normal surface expression of Ly49C/I and Ly49G2 early after BMT is time dependent, but MHC independent. Moreover, administration of hIL-15 is not sufficient to induce NK functional maturation early after BMT despite increased NK numbers.
Pharmacological Inhibition of EGFR Signaling Enhances G-CSF Induced Hematopoietic Stem Cell Mobilization.
Authors: Ryan Marnie A. , Xing Ellen , Schleimer David , Nattamai Kalpana , Daria Deidre , Liu Wei , Jansen Michael , Ratner Nancy , Le Cras Timothy , Van Zant Gary , Zheng Yi , Geiger Hartmut 
Published: April 2020

Abstract
Mobilization of hematopoietic stem and progenitor cells (HSPCs) from bone marrow into peripheral blood by the cytokine G-CSF has become the preferred source of HSPCs for clinical stem cell transplants. However, up to 10% of donors fail to mobilize sufficient numbers of stem cells impeding autologous transplants or significantly delaying transplant recovery time. Consequently, novel regimens are warranted to increase the number of stem cells in peripheral blood upon mobilization. Using a forward genetic approach in the mouse, we map the epidermal growth factor receptor (EGFR) to a genetic region on murine chromosome 11 modifying G-CSF-mediated HSPC mobilization. Expression levels of EGFR in HSPCs were inversely correlated with HSPC mobilization, implying a negative role for EGFR signaling in mobilization. Genetic reduction of EGFR activity (waved2 mice) or treatment with the EGFR inhibitor erlotinib increased stem cell mobilization up to 5-fold in combination with G-CSF. Increased mobilization due do alteration of EGFR activity correlated with reduced activity of Cdc42 and consequently, inhibition of Cdc42 activity in vivo by a specific Cdc42 inhibitor similarly enhanced mobilization. Our findings reveal a novel signaling pathway regulating stem cell mobilization and thus provide new rationale for targeted pharmacological approaches to further improve HSPC mobilization and thus transplantation outcomes.
Donor Bone Marrow Derived IL-17 Expressing Cells Exacerbate Chronic Graft-Versus-Host Disease in a Murine Bone Marrow Transplantation.
Authors: Kuroda Rie , Nishimura Ryosei , Sato Katsuaki , Maeba Hideaki , Naka Kazuhito , Niida Yo , Araki Raita , Iwakura Yoichiro , Koizumi Shoichi , Yachie Akihiro 
Published: April 2020

Abstract
Th17 is a newly identified T cell lineage that secretes the proinflamatory cytokine IL-17. Th17 cells have been shown to play a crucial role in mediating autoimmune diseases such as experimental autoimmune encephalomyelitis (EAE), arthritis, and colitis. However, recent study showed that donor Th17 cell ameliorated acute graft-versus-host disease (GVHD) due to the downregulation of Th1 differentiation in a murine BMT model. The role of IL-17 on developing chronic GVHD, which is pathologically similar to autoimmue diseases, remains unanswered. To this end, we compared the development of chronic GVHD between the lethally irradiated mice (Balb/c, H-2d) given IL-17 knockout(IL- 17KO, C57BL/6 background, H-2b) bone marrow (BM) cells and wild type BM cells with low dose WT splenocytes to induce sublethal acute GVHD and chronic GVHD subsequently. Up to day 60 after BMT no significant differences in clinical symptoms of GVHD including body weight changes were observed between the mice co-injected with IL-17 KO BM cells plus WT splenocytes and WT BM cells plus WT splenocytes. After day 60 the mice receiving WT BM cells plus WT splenocytes experienced weight loss accompanied by skin inflammatory changes, while mice receiving IL-17KO BM plus WT splenocytes showed minimal signs of GVHD as well as mice receiving IL-17 KO BM or WT BM alone. Recovery of body weight on day 160 after BMT was statistically different between two groups (p=0.035). Taken together, IL-17 was exacerbation factor of chronic GVHD, but not acute GVHD. Next we further evaluated the percentage of Th17 cells derived from BM cells (not from infused splenocytes) in the spleen on day 160 after BMT. Percentages of IL-17 expressing cells in the mice receiving WT BM plus WT splenocytes in spleen were significantly higher than those of WT BM alone receiving mice in CD4 (p=0.03) subpopulations. In conclusion, Th17 cells critically involved in the pathogenesis of chronic GVHD. Neutralizing IL-17 would be potent strategy for preventing chronic GVHD.
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