bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analysis of the Fate and Function of Antigen-Specific CD8 T Cells during B Cell Lymphoma Progression.
Authors: Brayer Jason , Cheng Fengdong , Horna Pedro , Suarez Ildefonso , Wang Hongwei , Sotomayor Eduardo M. 
Published: October 2019

Abstract
There is now overwhelming evidence that tumor-induced antigen (Ag)-specific T cell tolerance represents a critical problem in tumor immunology. Early studies of CD8 T cell tolerance equated peripheral tolerance with either ignorance or clonal deletion, although more recent evidence has suggested that this may be only partly accurate. While murine modeling outwardly supports the contention that high-affinity tumor-specific CD8 T cell responses are centrally deleted, cognate CD8 T cells displaying an Ag-experienced phenotype can nonetheless be detected in regional draining lymph nodes (dLN) or in non-lymphoid sites where the Ag is present. However, these CD8 T cells are typically deficient in one or more effector functions, including cytokine production, cytotoxicity, or proliferative capacity. To better define the state of Ag-specific CD8 T cell responsiveness in the face of progressive tumor, we adoptively transferred hemagglutinin (HA) Ag-specific Clone 4 (CLN4) CD8 T cells into animals bearing a genetically modified B cell lymphoma expressing HA as a model tumor antigen (A20HA). Analysis of the fate and function of these transferred antigen-specific CD8 T cells revealed that they encountered antigen in vivo, were capable of mounting an initial response to A20HA but this response was not sustained. Indeed, while a prominent CTL activation was observed in the spleen and draining lymph nodes of tumor bearing mice within 14 days of T cell transfer, responses (HA-specific proliferation, IFN-γ production and cytotoxicity) began to wane by day 21 after T cell transfer, and in particular their ability to produce IFN-γ. A similar pattern of transient activation followed by loss of CD8 T cell function has been also observed in an in vivo model of high-dose peptide induced antigen-specific CD8 T cell tolerance. Given our recent demonstration that the disruption of Stat3 signaling in APCs overcomes CD4 T cell tolerance we determined next whether Stat3 deficient APCs may be inherently better at cross-presenting tumor-Ags and elicit therefore a more productive and sustained CD8 T cell response. In an in vitro system in which tumor cells expressing a model tumor antigen (EL4mOVA) were cultured with APCs genetically devoid of Stat3 signaling and anti-OVA CD8 T-cells (OT-I), we found that these T cells displayed an enhanced function relative to antigen-specific CD8 T-cells that encountered antigen on APCs with an intact Stat3 signaling. Currently, we are investigating whether CD8 T-cell tolerance to tumor antigens occurred -or not- in tumor bearing mice with a genetic disruption of Stat3 signaling in APCs. Furthermore, given the emerging role of other members of the STAT family in regulation of APC function, we are exploring whether targeted disruption of Stat1, 4 and 6 can alter the ability of the CD8 T-cell to sustain a protective response or, more importantly to recover function once tolerance is induced.
Enhanced Platelet Aggregation and Thrombogenic Tendency in Adiponectin-Deficient Mice.
Authors: Kato Hisashi , Kashiwagi Hirokazu , Shiraga Masamichi , Honda Shigenori , Miyata Shigeki , Yamamoto Junichiro , Kurata Yoshiyuki , Funahashi Tohru , Shimomura Iichiro , Tomiyama Yoshiaki , Kanakura Yuzuru 
Published: October 2019

Abstract
Adiponectin is a 30 kDa protein secreted specifically from adipocytes and structurally composed of two distinct domains, C-terminal collagen-like domain and N-terminal complement C1q-like globular domain. Adiponectin is abundantly present in plasma at high concentration ranging from 2 to 30 μg/ml. The plasma levels of adiponectin decreased in patients with obesity and diabetes. Recently it has been demonstrated that adiponectin has an anti-atherogenic activity. Hypoadiponectinemia is an independent risk factor for coronary artery disease in men. However, the role of adiponectin in hemostasis and thrombosis still remains obscure. In this study, we examined its role in hemostasis and thrombosis using adiponectin-deficient (APN-KO) mice (Nat. Med. 2002 Maeda et al.). APN-KO mice were fed by normal chaw and studied at 8–12 weeks old. There were no differences in platelet counts, PT, APTT and plasma fibrinogen levels between APN-KO and Wild-Type mice. Neither Wild-Type nor APN-KO mice showed detectable atherosclerotic lesion in carotid artery as well as whole aorta. We examined tail-bleeding times as a measure of primary hemostasis. The tail bleeding time was 96.9 ± 34.9 seconds in APN-KO mice, which was shorter than that in wild type mice (130.9 ± 52.1 seconds, n=30, p<0.05). We next studied thrombus formation in mice carotid artery using He-Ne laser induced in vivo thrombus formation model. Thrombus formation was induced by the interaction of irradiated He-Ne laser with evans blue dye injected into blood flow. The thrombus volumes formed during 10 minutes were significantly larger in APN-KO mice (6.74 ± 2.87 x 107 arbitrary units for wild-type v.s. 13.4 ± 4.25 x 107 arbitrary units for APN-KO mice, n=10, p<0.01). Adenovirus-mediated supplement of adiponectin compensated for the thrombotic tendency in APN-KO mice. In order to clarify the effects of adiponectin on platelet functon, we performed ex vivo experiments. In platelet aggregation studies under stirring conditions using platelet-rich plasma, platelet aggregation induced by low concentrations of agonists (ADP 2.5μM, collagen 2.5μg/ml, PAR4 peptide 75μM) was enhanced in APN-KO mice. Again the adenovirus-mediated supplement of adiponectin compensated for the enhancement of platelet aggregation. We next studied the thrombus formation on collagen coated surface under flow conditions. The thrombus formation was enhanced in APN-KO mice under shear rate at 250s−1. Our data provide a first evidence that adiponectin plays a role in hemostasis and thrombosis as a negative modulator of platelet function.
Multiple Hepatic Clearance Receptors Facilitate Elimination of Secretory Mucins that Can Enter the Bloodstream in Pathological States and Generate Platelet-Rich Microthrombi.
Authors: Wahrenbrock Mark G. , Varki Ajit 
Published: October 2019

Abstract
Epithelial cells that line hollow organs typically secrete mucins and their proteolytic fragments vectorially, into the lumen of the organ. Fragments of these large, heterogeneously O-glycosylated molecules can enter the blood stream during injury, inflammation or malignancy involving such organs. We have previously shown that intravenous injection of human carcinoma mucin fragments into mice triggered a “Trousseau”-like syndrome consisting of extensive formation of platelet- and leukocyte-rich microthrombi that were thrombin-independent, but L-and P-selectin-dependent and heparin-sensitive (Wahrenbrock et al., 2003, J Clin Invest, 112, 853–62). Thus, we hypothesized that mechanisms should exist to clear such mucin fragments when they enter the bloodstream in various pathological states. Indeed, intravenously injected radiolabeled mucin fragments had a circulating half-life of ~1 minute in mice, due to rapid and specific clearance by liver reticuloendothelial cells. Competition of uptake by inhibitors of known glycan-recognizing hepatic clearance receptors showed that several overlapping and non-overlapping systems work in concert to remove mucin fragments from the circulation. The systems involved include the hepatic asialoglycoprotein receptor, the macrophage Gal/GalNAc and Mannose receptors, and the endothelial S4GGnM and hyaluronan receptors. Studies of genetically deficient mice, and competition studies amongst various differently glycosylated mucins confirm this result. Thus, multiple hepatic clearance receptors collaborate to varying degrees to ensure elimination of the many polydisperse and differentially glycosylated forms of secretory mucins that might enter the blood circulation from various hollow organs, thus limiting their ability to cause pathology involving disseminated platelet and leukocyte aggregation. This process could also potentially modulate circulating levels of mucin epitopes that are sometimes used as diagnostic criteria in cancer (e.g., CA125, CA19-9 etc.). Furthermore, it can explain why mucin-type clustered O-glycosylation is very uncommon on circulating plasma proteins.
Sequential Treatment with Reduced Intensity Allogeneic Stem Cell Transplantation and Imatinib for Chronic Myelogenous Leukemia (CML.
Authors: Champlin Richard , Ghosh Shubhra , McCormick Gloria , Andersson Borje , de Lima Marcos , Anderlini Paolo , Qazilbash Muzaffar , Giralt Sergio , Cortes Jorge 
Published: October 2019

Abstract
Chronic myelogenous leukemia is uniquely sensitive to the graft-vs-malignancy effects. Donor lymphocyte infusion (DLI) can induce a high rate of durable remissions in patients relapsing after BMT. Imatinib mesylate may also induce remission in patients with recurrent disease post BMT. This suggests a strategy of sequential therapy using a reduced intensity allogeneic transplant to achieve initial cytoreduction with post transplant imatinib and DLI for recurrent disease as an approach to reduce the risks associated with allogeneic transplantation. We also assessed whether the addition of imatinib to the preparative regimen could be done without increased toxicity to take advantage of the synergistic effects of imatinib with cytotoxic chemotherapy. Patients received a reduced intensity regimen of imatinib (800 mg/d), busulfan ( 8 mg/m2 IV), fludarabine (160 mg/m2), Thymoglobulin (5 mg/kg) and allogeneic stem cell transplantation. Patients receive tacrolimus and mini-methotrexate for GVHD prophylaxis. Those who had molecular evidence of disease at 3 months receive imatinib and those with residual disease 3 months later receive DLI.
14 patients with Ph+ CML have been entered and have follow-up greater than 100 days. 8 had a matched sibling, 5 an unrelated donor and 1 a one antigen mismatched related donor. 4 received marrow and 10 blood progenitor cell transplants. All had received prior imatinib and all except 2 had failed to achieve a major cytogenetic response. 7 were in first chronic or accelerated phase and 7 were in > 2nd chronic phase after prior accelerated phase or blast crisis. All had hematologic control while receiving imatinib-based therapy. Median age was 48 (range 23–70) years.
All patients achieved engraftment and none have died from treatment related causes. 3 developed grade 1–2 acute GVHD and 4 have developed chronic GVHD. 13 patients achieved cytogenetic complete remission, one patient failed to respond and was taken off study. 3 had cytogenetic progression with one having fatal recurrence of lymphoid blast crisis. 9 patients who were pcr positive for bcr-abl rearrangement at 3 months received imatinib; 7 have had ongoing disease reduction by quantitative pcr, 1 currently has no response and 1 patient had progressive disease and was taken off study. None have received DLI. 13 patients remain alive with 11 in cytogenetic remission.
In summary, addition of imatinib to the preparative regimen was not associated with increased toxicity. This strategy allows for allogeneic transplantation using a reduced intensity regimen with capture of persistent or recurrent disease by post transplant imatinib and/or DLI. The low rate of severe morbidity and treatment related mortality makes this approach attractive for CML patients failing to have an optimal initial response to imatinib based therapy.
The Activation of Stat3 by the Stk Receptor Tyrosine Kinase Requires Src Kinases and Gab2, and Is Essential for Friend Virus Induced, Epo-Independent Growth of Primary Erythroid Cells.
Authors: Ni Shuang , Heal Hami , Xu Jie , Paulson Robert , Correll Pamela H. 
Published: October 2019

Abstract
Friend virus-induced erythroleukemia is a model for the study of the multi-stage nature of carcinogenesis. The early stage of the disease is characterized by a polyclonal expansion of infected erythroid precursor cells, and the later stage is marked by the emergence of fully transformed cells in the spleen, blood, bone marrow and liver, leading to the development of erythroleukemia. Previous findings have demonstrated that a naturally occurring, N-terminally truncated form of the stk receptor tyrosine kinase (Sf-stk) provides signals necessary for the polycolonal expansion of infected cells. Signal transducer and activator of transcription (Stat) proteins play an important role in normal and malignant hematopoiesis. Moreover it has been shown that growth factors can induce Stat3 in a Src family kinase (SFK)-dependent manner. Here we show that dominant negative Stat3 and c-Src significantly inhibit the BFU-e and CFU-e colony number induced by friend virus. In addition, the non-specific SFK inhibitor PP1 also abrogated Epo-independent colony formation. Moreover we found that the inhibition of SFKs by PP1 suppresses Stat3 tyrosine phosphorylation activated by Sf-stk. To elucidate the signaling mechanism by which Sf-stk activates Stat3, we mutated the docking site tyrosines to phenylalanine. Our results indicated that the mutation of Y436F eliminates Sf-stk-induced Stat3 tyrosine phosphorylation. Studies from our lab have further demonstrated that tyrosine 436 of Sf-stk is essential for the cytokine-independent growth of primary erythroblasts induced by Friend virus, by providing a docking site for Grb2, which recruits Gab2 to induce erythroleukemia. To further determine the relationship between Gab2 and Stat3, we generated fusion proteins, in which Sf-stk lacking the docking site tyrosines is fused to Gab2 or Gab1. The Sf-stk/Gab2, but not Sf-stk/Gab1, fusion protein supported Epo-independent colony formation and induced Stat3 tyrosine phosphorylation. In conclusion, these results suggest that SFKs, Gab2 and Stat3 are all important in Friend virus induced erythroleukemia mediated by Sf-stk, and that Gab2 and SFKs lie upstream of Stat3 in this signaling pathway.
Flt3 Internal Tandem Duplications Cooperate with Wnt Signaling in Leukemic Signal Transduction.
Authors: Tickenbrock Lara , Schwable Joachim , Wiedehage Markus , Steffen Bjoern , Choudhary Chunaram , Berdel Wolfgang E. , Muller-Tidow Carsten , Serve Hubert 
Published: October 2019

Abstract
Flt3 internal tandem duplications cooperate with Wnt signaling in leukemic signal transduction
Lara Tickenbrock, Joachim Schwable, Markus Wiedehage, Bjoern Steffen, Chunaram Choudhary, Wolfgang E. Berdel, Carsten Muller-Tidow and Hubert Serve
Department of Medicine, Hematology and Oncology, University of Muenster, D-48149 Muenster, Germany
The type III receptor tyrosine kinase (RTK) Flt3 plays an important role in survival and proliferation of hematopoietic progenitor cells. Somatic mutations of Flt3 consisting of internal tandem duplications (ITD) occur in 25% of patients with acute myeloid leukemia (AML), and are associated with a poor prognosis. They result in Flt3-ligand (FL) independent kinase activation of Flt3. The Wnt signal transduction pathway has recently been implicated to be an important regulator of early hematopoietic stem cell fate decisions. Also, we previously showed that activation of Wnt-dependent Tcf transcriptional activity is induced by the leukemia-associated fusion proteins PML-RAR? and AML1-ETO. Here, we show that Flt3-ITD mutations enhance basal and Wnt3a-stimulated Tcf activity in myeloid cells. Microarray experiments analyzing Flt3-ITD target genes in 32D cells revealed up to 8-fold induction of Frizzled-4, a cell surface receptor for Wnt proteins, by Flt3-ITD mutations. This could be verified by real-time RT-PCR and Western Blot analyses. In functional analyses, we explored the synergism of Flt3-ITD and the activation of Wnt signaling. Flt3-ITD mutations induced the accumulation of ?-Catenin and TCF-dependent transcriptional activity. Also, the presence of Flt3-ITD highly sensitized cells for ?-Catenin-induction by the Wnt3a. Wnt3a incubation enhanced 32D cell proliferation in the presence of activated Flt3 receptors. More importantly, Flt3-ITD-mediated clonogenic growth highly depended on the activity of Tcf transcription factors, since transient transfection of Flt3-ITD cells with dominant negative TCF4 almost abolished 32D cell colony growth. Our results indicate that Flt3-ITD mutations mediate their leukemogenic effects in part through the activation of Wnt-dependent signaling pathways, possibly defining this signal system as a converging point of leukemogenic events elicited by Flt3-mutations and leukemia-associated fusion proteins.
Impact of Cytogenetics on Outcome of Mismatched Unrelated Donor Hematopoietic Stem Cell Transplantation for Adults with AML.
Authors: Tallman Martin , Dewald Gordon , Lazarus Hillard , Gandham Sharavi , Nelson Gene , Logan Brent , Rowe Jacob , Litzow Mark , Keating Armand , Mehta Jayesh , Wetzler Meir , Warren Tanya , Weisdorf Daniel 
Published: October 2019

Abstract
Matched unrelated donor hematopoietic stem cell transplantation (MUD HSCT) is a potentially curative treatment for patients with acute myeloid leukemia (AML). The graft-versus-leukemia (GVL) effect may be potent enough to overcome the otherwise poor prognosis associated with AML though its efficacy for high risk cytogenetic subgroups is uncertain. To test this hypothesis, we analyzed outcomes by cytogenetic risk group in 324 patients in first complete remission (CR1), and 440 in CR2 undergoing NMDP-facilitated MUD HSCT between 1988–2002. Using the SWOG/ECOG classification of cytogenetic risk groups (Slovak et al. Blood, 2000) cytogenetics were classified as favorable in 14% of patients, intermediate in 71% and unfavorable in 16%. 56% of the patients were male and 42% were > 35 years at HSCT. 76% of patients and donors were matched at HLA-A, -B and -DRB1, 17% were mismatched at one or more loci and 7% were potentially matched (serologically matched at HLA-A and -B and potentially allele matched at -DR).
Disease Status N Kaplan-Meier Estimate for Survival at 5 years Kaplan-Meier Estimate for Disease-Free Survival at 5 years Cumulative Incidence for 100 Day Transplant-Related Mortality Cumulative Incidence for Relapse at 5 years * p-value indeterminate; ** p=0.01 CR1 324 32 ± 6% 32 ± 5% 32 ± 5% 18 ± 4%     Intermediate 227 33 ± 7% 32 ± 7% 31 ± 6% 16 ± 5%*     Unfavorable 85 31 ± 11% 31 ± 10% 29 ± 10% 23 ± 9%* CR2 440 36 ± 5% 35 ± 5% 25 ± 4% 16 ± 3%     Favorable 93 46 ± 10% 44 ± 10% 25 ± 9% 10 ± 6%**     Intermediate 313 33 ± 6% 32 ± 5% 27 ± 5% 16 ± 4%**     Unfavorable 34 37 ± 17% 38 ± 16% 15 ± 12% 32 ± 15%**
These data suggest that with the exception of the 5-year relapse rate, results of cytogenetics have little apparent influence on the outcome for patients undergoing MUD HSCT for AML in CR1. In CR2, results in patients with favorable cytogenetics appear to be better than those with intermediate or unfavorable cytogenetics, but are not statistically significantly different. Effective GVL and protection against relapse is observed, even in high risk cytogenetic subgroups. In this retrospective study, other prognostic factors may influence the outcome, but overall survival for patients with unfavorable cytogenetics appears at least as good as previously reported for matched sibling HSCT.
An In-Frame Deletion of Six Amino Acids and a Point Mutation in the Disintegrin Domain of ADAMTS-13 Associates with a Case of Congenital Thrombotic Thromocytopenic Purpura.
Authors: Tao Zhenyin , Nolasco Leticia , Aubrey Bernardo , Rice Lawrence , Moake Joel F. , Dong Jing-Fei 
Published: October 2019

Abstract
Thrombotic thrombocytopenic purpura (TTP) is characterized by severe thrombocytopenia, hemolytic anemia, and diffuse and non-focal neurological findings. Microthrombi found in these patients are predominantly composed of platelets and von Willebrand factor (VWF). Recent studies suggest that the systemic thrombosis in TTP is mostly due to the congenital or acquired deficiency of the VWF-cleaving metalloprotease ADAMTS-13, which cleaves the ultra-large and hyperreactive VWF to smaller and less active form found in plasma. Most congenital cases of TTP have so far been identified in children. Here, we report a 60-year-old Caucasian man with a history of chronic relapsing TTP over thirty years, requiring plasma transfusion every 24 days in recent years. Repeat assays showed no ADAMTS13 activity in patient’s plasma under both static and flow conditions without inhibitors being detected. We therefore examined the possible genetic defects in the ADAMTS-13 gene of this patient. Genomic DNA was extracted from patient’s white blood cells and exons of ADAMTS-13 gene were amplified by polymerase chain reaction. The amplified DNA fragments were then screened for mutations by direct DNA sequencing. We identified a deletion of 18 base pairs from G1095 to G1112 (GTGCTCCAAGGGTCGCTG) in the exon10 of ADAMTS-13 gene, resulting in a deletion of six amino acids (C366 to C371) in the disintegrin domain of the metalloprotease. A point mutation (W365C) occurred immediately before the deletion due to a nucleotide realignment. The patient is heterozygote for the deletion. This is the first report of a deletion mutant (without frame shift and truncations) in the disintegrin region that has previously been demonstrated as critical for the ADAMTS-13 function by in vitro mutagenesis, epitope mapping of autoantibody to the metalloprotease in patients with adult acquired TTP, and identification of natural occurring mutations in patients with congenital TTP. Our ongoing studies are to determine the impact of these two mutations on the synthesis, release, and cleavage of ADAMTS-13.
Low Dose Ara-C Versus Hydroxyurea with or without Retinoid in Older Patients Not Considered Fit for Intensive Chemotherapy: The UK NCRI AML14 Trial.
Authors: Burnett Alan K. , Milligan Donald , Prentice Archie G. , Goldstone Anthony H. , McMullin Mary F. , Wheatley Keith 
Published: October 2019

Abstract
There is no adequate treatment for older patients with AML who are not considered fit for intensive chemotherapy who comprise a significant proportion of the AML population. As part of the ongoing NCRI (formerly MRC) AML14 Trial in patients over 60 years patients were randomised to Low Dose Ara-C (20mg bd for 10 days every 4–6 weeks) versus Hydroxycarbamide (Hydroxyurea). Because of preclinical studies showing sensitization to Ara-C, patients were in addition randomised to receive All-transretinoic acid or not (45mgs/m2 for 60 days).
Two hundred and four patients entered; 129 had a WHO score of <2; 155 patients were >65 yrs; 108 had do novo, 53 secondary disease and 28 had high risk MDS (blasts >10%). One hundred and ninety-nine patients entered the HU vs LD-Ara-C randomisation and 204 entered the ATRA randomisation. The arms were balanced with respect to age; sex; disease type; WBC and performance score.
Complete remission was seen in 1 of 92 (1%) patients in the HU arm and 15 of 94 (17%) in the LD Ara-C arm (P=0003). Overall survival was considerably improved (hazard ratio 0.61, 95% Cl 0.45 to 0.82, p=0.001). This improvement in outcome was not obtained at the expense of less well tolerated treatment: toxicity and supportive care requirements were similar between the two groups. However, there were no significant differences in outcome between patients given ATRA or not overall or within the treatment arms, although numbers were too small to rule out moderate benefits or disbenefits of treatment (hazard ratio for OS 0.97, 95% Cl 0.73 to 1.28, p=0.8).
We conclude that LD-Ara-C in the schedule chosen could be adopted as a standard of care for older patients not fit for intensive chemotherapy but the outcome remains poor. Future strategies could combine Low Dose Ara-C with novel agents. This trial received a research grant from the UK Leukaemia Research Fund.