bluuebunny/crossref_metadata_2025_split huggingface dataset:
Interleukin-3–Induced Activation of the JAK/STAT Pathway Is Prolonged by Proteasome Inhibitors
Authors: Callus Bernard A. , Mathey-Prevot Bernard 
Published: October 2019

AbstractOne facet of cytokine receptor signaling involves the activation of signal transducers and activators of transcription (STATs). STATs are rapidly activated via tyrosine phosphorylation by Janus kinase (JAK) family members and subsequently inactivated within a short period. We investigated the effect of proteasome inhibition on interleukin-3 (IL-3) activation of the JAK/STAT pathway following stimulation of Ba/F3 cells. Treatment of Ba/F3 cells with the proteasome inhibitor,N-acetyl-l-leucinyl-l-leucinyl-norleucinal (LLnL), led to stable tyrosine phosphorylation of the IL-3 receptor, beta common (βc), and STAT5 following stimulation. The effects of LLnL were not restricted to the JAK/STAT pathway, as Shc and mitogen-activated protein kinase (MAPK) phosphorylation were also prolonged in LLnL-treated cells. Further investigation showed these stable phosphorylation events were the result of prolonged activation of JAK2 and JAK1. These observations were confirmed using pharmacologic inhibitors. In the presence of LLnL, stable phosphorylation of STAT5 and βc was abrogated if the tyrosine kinase inhibitor, staurosporine, was added. The effect of staurosporine on STAT5 phosphorylation could be overcome if the phosphatase inhibitor, vanadate, was also added, suggesting phosphorylated STAT5 could be stabilized by phosphatase, but not by proteasome inhibition per se. These observations are consistent with the hypothesis that proteasome-mediated protein degradation can modulate the activity of the JAK/STAT pathway by regulating the deactivation of JAK.
Growth-Supporting Activities of Fibronectin on Hematopoietic Stem/Progenitor Cells In Vitro and In Vivo: Structural Requirement for Fibronectin Activities of CS1 and Cell-Binding Domains
Authors: Yokota Takafumi , Oritani Kenji , Mitsui Hideki , Aoyama Keisuke , Ishikawa Jun , Sugahara Hiroyuki , Matsumura Itaru , Tsai Schickwann , Tomiyama Yoshiaki , Kanakura Yuzuru , Matsuzawa Yuji 
Published: October 2019

AbstractFibronectin (FN) is supposed to play important roles in various aspects of hematopoiesis through binding to very late antigen 4 (VLA4) and VLA5. However, effects of FN on hematopoietic stem cells are largely unknown. In an effort to determine if FN had a growth-supporting activity on hematopoietic stem cells, human CD34+/VLA4bright/VLA5dullhematopoietic stem cells and a murine stem cell factor (SCF)-dependent multipotent cell line, EML-C1, were treated with or without FN in a serum and growth-factor–deprived medium, and then subjected to clonogenic assay in the presence of hematopoietic growth factors. The pretreatment of the CD34+ cells with FN gave rise to significantly increased numbers of granulocyte-macrophage colony-forming units (CFU-GM), erythroid burst colony-forming units, and mixed erythroid-myeloid colony-forming units. In addition, the numbers of blast colony-forming units and CFU-GM that developed after culture of EML-C1 cells with SCF and the combination of SCF and interleukin-3, respectively, were augmented by the pretreatment with FN. The augmented colony formation by FN was completely abrogated by the addition of CS1 fragment, but not of GRGDSP peptide, suggesting an essential role of FN-VLA4 interaction in the FN effects. Furthermore, the effects of various FN fragments consisting of RGDS-containing cell-binding domain (CBD), heparin-binding domain (HBD), and/or CS1 portion were tested on clonogenic growth of CD34+ cells. Increased colony formation was induced by CBD-CS1 and CBD-HBD-CS1 fragments, but not with other fragments lacking CBD or CS1 domains, suggesting that both CS1 and CBD of FN were required for the augmentation of clonogenic growth of hematopoietic stem/progenitor cells in vitro. In addition to the in vitro effects, the in vivo administration of CBD-CS1 fragment into mice was found to increase the numbers of hematopoietic progenitor cells in bone marrow and spleen in a dose-dependent manner. Thus, FN may function on hematopoietic stem/progenitor cells as a growth-supporting factor in vitro and in vivo.
Factor XIIIa Cross-Linking of the Marburg Fibrin: Formation of αm·γn-Heteromultimers and the α-Chain–Linked Albumin·γ Complex, and Disturbed Protofibril Assembly Resulting in Acquisition of Plasmin Resistance Relevant to Thrombophila
Authors: Sugo Teruko , Nakamikawa Chizuko , Takebe Mikihiro , Kohno Isao , Egbring Rudorf , Matsuda Michio 
Published: October 2019

AbstractThe truncated Aα-chain of fibrinogen Marburg is partly linked with albumin by a disulfide bond. Based on the recovery of the first six amino acid residues assigned to the subunit polypeptides of fibrinogen (the Aα-and γ-chains) and albumin, 0.33 mol of albumin was estimated to be linked to 1 mol of the Marburg fibrinogen. When the Marburg fibrinogen was clotted with thrombin-factor XIIIa-Ca2+, various αmγnheteromultimers were produced, and part of the albumin was cross-linked to the γ-chain. Acid-solubilized Marburg fibrin monomer failed to form large aggregates that could be detected by monitoring turbidity at A350, but it was able to enhance tissue-type plasminogen-activator–catalyzed plasmin generation, though not as avidly as the normal control, indicating that the double-stranded protofibrils had, to some extent, been constructed. This idea seems to be supported by normal factor XIIIa–catalyzed cross-linking of the fibrin γ-chains. However, the cross-linked Marburg fibrin, being apparently fragile and translucent, was highly resistant against plasmin, and its subunit components were considerably retained for 48 hours as noted by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Although the exact mechanisms are still unclear, the albumin-incorporated factor XIIIa–cross-linked Marburg fibrin seems to have undergone a critical structural alteration(s) to acquire resistance against plasmin. This aquisition of plasmin resistance may be contributed to the postoperative pelvic vein thrombosis and recurrent pulmonary embolisms in the patient after caesarian section for her first delivery at the age of 20 years.
High CD30 Ligand Expression by Epithelial Cells and Hassal's Corpuscles in the Medulla of Human Thymus
Authors: Romagnani Paola , Annunziato Francesco , Manetti Roberto , Mavilia Carmelo , Lasagni Laura , Manuelli Cinzia , Vannelli Gabriella B. , Vanini Vittorio , Maggi Enrico , Pupilli Cinzia , Romagnani Sergio 
Published: October 2019

AbstractCD30 is a member of tumor necrosis factor (TNF) receptor superfamily that is expressed by activated T cells in the presence of interleukin-4 (IL-4). Although CD30 can mediate a variety of signals, CD30-deficient mice have impaired negative selection of T cells, suggesting that at least in the context of murine thymus, CD30 is a cell death–mediating molecule. The ligand for CD30 (CD30L) is a membrane-associated glycoprotein related to TNF, which is known to be expressed mainly by activated T cells and other leukocytes. However, the nature of CD30L-expressing cells involved in the interaction with CD30+ thymocytes is unclear. We report here that in postnatal human thymus the great majority of CD30+ cells are double positive (CD4+CD8+), activated, IL-4 receptor–expressing T cells which selectively localize in the medullary areas. Moreover, many medullary epithelial cells and Hassal's corpuscles in the same thymus specimens showed unusually high expression of CD30L in comparison with other lymphoid or nonlymphoid tissues. These findings provide additional information on the nature and localization of CD30+ thymocytes and show that epithelial cells are the major holder of CD30L in the thymic medulla.
A Strong Expression of CD44-6v Correlates With Shorter Survival of Patients With Acute Myeloid Leukemia
Authors: Legras S. , Günthert U. , Stauder R. , Curt F. , Oliferenko S. , Kluin-Nelemans H.C. , Marie J.P. , Proctor S. , Jasmin C. , Smadja-Joffe F. 
Published: October 2019

AbstractCD44 is a ubiquitous cell-surface glycoprotein that displays many variant isoforms (CD44v) generated by alternative splicing of exons 2v to 10v. The expression of variant isoforms is highly restricted and correlated with specific processes, such as leukocyte activation and malignant transformation. We have herein studied CD44v expression in acute myeloid leukemia (AML) and, for comparison, in normal myelopoiesis. Protein expression of total CD44 and of CD44-3v, -6v, and -9v isoforms has been measured using specific monoclonal antibodies and flow cytometry. The composition of variant exon transcripts has been analyzed by semi-quantitative reverse transcriptase-polymerase chain reaction followed by Southern hybridization with exon-specific probes. Our data show that (1) CD44-6v isoforms are expressed on 12.0% ± 2.5% of normal CD34+ cells; this expression is sharply upregulated through monopoiesis and, inversely, downregulated during granulopoiesis. Also, CD44-3v and CD44-9v isoforms are detected on 10% and 14% of normal monocytes, respectively. (2) Sixty-nine from a total of 95 AML patients display a variable proportion (range, 5% to 80%) of CD44-6v+ leukemic cells. (3) A shorter overall survival characterizes the group of AML patients displaying more than 20% of CD44-6v+ leukemic cells (8 months v 18 months, P < .02). These data suggest, for the first time, that the protein expression of CD44-6v containing isoforms may serve as a new prognostic factor in AML.
Raised Neutrophil Phospholipase A2 Activity and Defective Priming of NADPH Oxidase and Phospholipase A2 in Sickle Cell Disease
Authors: Mollapour Elahe , Porter John B. , Kaczmarski Richard , Linch David C. , Roberts Pamela J. 
Published: October 2019

AbstractIntermittent painful crises due to vasoocclusion are the major clinical manifestation of sickle cell disease (SCD), but subclinical episodes may also occur. There is sparse evidence for the involvement of neutrophils in the pathophysiology of SCD, but production of cytokines by the damaged endothelium might influence neutrophil function and modulate responses to subsequent cytokine exposure. In addition, the activation of neutrophils in the microcirculation could itself exacerbate vasoocclusion. To test whether neutrophil inflammatory responses were altered in SCD, neutrophil phospholipase A2 and NADPH oxidase activity in response to in vitro priming by granulocyte-macrophage colony-stimulating factor (GM-CSF) and tumor necrosis factor-α (TNF-α) were measured both during and between painful crises. Resting levels of neutrophil phospholipase A2 activity in steady-state SCD (4.0% ± 0.5% of total cell radioactivity) were raised relative to control values (2.0% ± 0.2%, n = 10, P = .008). There was no defect of agonist-stimulated phospholipase A2 or NADPH oxidase activity in steady-state SCD; however, the ability of phospholipase A2 to respond to priming with GM-CSF was attenuated to 63% ± 17% of control values (n = 10,P = .04). Similarly, neutrophil NADPH oxidase activity after priming with GM-CSF and TNF-α was, respectively, 65% ± 11% (n = 7, P = .03) and 57% ± 7% of control (n = 10, P = .007) in steady-state disease, and was further reduced during painful vasoocclusive crises to 34% ± 9% and 25% ± 3% of control for GM-CSF and TNF-α, respectively. These data were not explained by poor splenic function or any racial factor, as normal cytokine responses were seen in splenectomized patients in remission from Hodgkin's disease and in healthy Afro-Caribbean subjects. Abnormal neutrophil cytokine priming responses were not observed in either patients with rheumatoid arthritis or iron-deficiency anemia. Our findings are indicative of an ongoing inflammatory state in SCD between painful crises involving neutrophil activation and an abnormality of cytokine-regulated neutrophil function, which may compromise the host defenses against certain microorganisms.
Galectin-3 Activates the NADPH-Oxidase in Exudated but not Peripheral Blood Neutrophils
Authors: Karlsson Anna , Follin Per , Leffler Hakon , Dahlgren Claes 
Published: October 2019

AbstractGalectin-3, a lactose-binding mammalian lectin that is secreted from activated macrophages, basophils, and mast cells, was investigated with respect to its ability to activate the human neutrophil NADPH-oxidase. The galectin-3–induced activity was determined with in vivo exudated cells (obtained from a skin chamber) and compared with that of peripheral blood neutrophils. Galectin-3 was found to be a potent activator of the NADPH-oxidase only in exudated neutrophils and the binding of galectin-3 to the surface of these cells was increased compared with peripheral blood cells. Different in vitro priming protocols resulting in degranulation were used to mimic the exudation process in terms of increasing the receptor exposure on the cell surface. Galectin-3 could induce an oxidative response similar to that in exudated cells only after a significant amount of the intracellular organelles had been mobilized. This increase in oxidative response was paralleled by an increased binding of galectin-3 to the surface of the cells. The major conclusion of the study is that galectin-3 is a potent stimulus of the neutrophil respiratory burst, provided that the cells have first experienced an extravasation process. The results also imply that the neutrophil response to galectin-3 could be mediated through receptors mobilized from intracellular granules, and we report the presence of galectin-3–binding proteins in such organelles.
Reduced Ex Vivo Interleukin-8 Production by Neutrophils in Septic and Nonseptic Systemic Inflammatory Response Syndrome
Authors: Marie Christelle , Muret Jane , Fitting Catherine , Losser Marie-Reine , Payen Didier , Cavaillon Jean-Marc 
Published: October 2019

AbstractEx vivo cytokine production by circulating lymphocytes and monocytes is reduced in patients with infectious or noninfectious systemic inflammatory response syndrome. Very few studies have addressed the reactivity of polymorphonuclear cells (PMN). To analyze further the relative contribution of systemic inflammatory response syndrome alone or in combination with infection we studied the interleukin-8 (IL-8) production by PMN isolated from patients who had undergone cardiac surgery with cardiopulmonary bypass (CPB) and patients with sepsis. Cells were activated with either lipopolysaccharide (LPS) or heat-killed streptococci. Compared with healthy controls, the release of IL-8 by PMN in both groups of patients was significantly reduced whether activated by LPS, independently of its concentration and origin, or by heat-killed streptococci. These observations suggest that stressful conditions related to inflammation, independently of infection, rapidly dampened the reactivity of circulating PMN. We investigated whether the observed diminished reactivity of PMN might reflect an endotoxin tolerance phenomenon. Our in vitro experiments with PMN from healthy controls indicated that PMN could not be rendered tolerant stricto sensu. However, our data suggested that LPS-induced mediators such as IL-10 may be responsible for the observed anergy in patients.
Mechanisms of Transcription in Eosinophils: GATA-1, but not GATA-2, Transactivates the Promoter of the Eosinophil Granule Major Basic Protein Gene
Authors: Yamaguchi Yuji , Ackerman Steven J. , Minegishi Naoko , Takiguchi Masaki , Yamamoto Masayuki , Suda Toshio 
Published: October 2019

AbstractGranule major basic protein (MBP) is expressed exclusively in eosinophils, basophils, and placental trophoblasts. To identify thecis-elements and transcription factors involved in regulating MBP expression, we subcloned 3.2 kb of sequence upstream of the exon 9 transcriptional start site (P2 promoter) and serial 5′ deletions into the pXP2 luciferase reporter vector. An 80% decrement in promoter activity was obtained when MBP sequences between bp −117 to −67 were deleted. To identify transcription factors that bind to and transactivate through the bp −117 to −67 region, we first compared the upstream genomic sequences of human and murine MBP; a potential GATA binding consensus site was conserved in the 50-bp region between the two genes. To determine which GATA proteins bind this consensus site, we performed electrophoretic mobility shift assays (EMSAs), which showed that both GATA-1 and GATA-2 can bind to this consensus site. To determine the functionality of this site, we tested whether GATA-1 and GATA-2, either individually or in combination, can transactivate the MBP promoter in the Jurkat T cell line. Cotransfection with a GATA-1 expression vector produced 20-fold augmentation of MBP promoter activity, whereas GATA-2 had no activity. In contrast, combined cotransfection of GATA-1 and GATA-2 decreased the ability of GATA-1 to transactivate the MBP promoter by approximately 50%. Our results provide the first evidence for a GATA-1 target gene in eosinophils, a negative regulatory role for GATA-2 in MBP expression, and possibly eosinophil gene transcription in general during myelopoiesis.
Low Transplant Mortality in Allogeneic Bone Marrow Transplantation for Acute Myeloid Leukemia: A Randomized Study of Low-Dose Cyclosporin Versus Low-Dose Cyclosporin and Low-Dose Methotrexate
Authors: Zikos P. , Van Lint M.T. , Frassoni F. , Lamparelli T. , Gualandi F. , Occhini D. , Mordini N. , Berisso G. , Bregante S. , De Stefano F. , Soracco M. , Vitale V. , Bacigalupo A. 
Published: October 2019

AbstractSixty patients undergoing allogeneic bone marrow transplant for acute myeloid leukemia (AML) in first remission (CR1; n = 49) or more advanced phase (n = 11) were entered in a prospective trial of graft-versus-host disease (GvHD) prophylaxis: low-dose cyclosporin A (IdCSA; 1 mg/kg/d from day −1 to +20 day; n = 28) or IdCSA plus low-dose methotrexate (IdMTX; 10 mg/m2 for day +1, 8 mg/m2 for days +3, +6, and +11; n = 32). Primary end points were acute GvHD (aGvHD) and transplant-related mortality (TRM); secondary end points were relapse and survival. The conditioning regimen consisted of cyclophosphamide (120 mg/kg) and fractionated total body irradiation (3.3 Gy/d for 3 consecutive days). The actuarial risk of developing aGvHD grade II-III was 61% for IdCSA alone and 34% for IdCSA + IdMTX (P = .02). The actuarial risk of TRM at 1 year was 11% versus 13%, respectively, and older patients (≧29 years) had higher TRM than younger patients (22% v 5%,P = .01). The age effect was significant in the IdCSA group (P = .04) but not in the IdCSA + IdMTX group (P = .1). The median follow-up is 4.4 years, with an overall actuarial survival of 78% for CR1 patients and 36% for patients with advanced disease. For patients in CR1 the outcome of the two regimens was as follows: survival 77% versus 80% (P = .6), relapse 20% versus 9% (P = .1), and TRM 13% versus 17% (P = .6). This study suggests that TRM can be reduced in AML patients undergoing allogeneic marrow transplants with a mild conditioning regimen and low-dose immunosuppression, and this translates in a 78% 5-year survival for CR1 patients. Beyond CR1 the major obstacle remains leukemia relapse, which is not prevented by low-dose in vivo immunosuppression.
Oligoclonal Protein Bands and Ig Isotype Switching in Multiple Myeloma Treated With High-Dose Therapy and Hematopoietic Cell Transplantation
Authors: Zent C.S. , Wilson C.S. , Tricot G. , Jagannath S. , Siegel D. , Desikan K.R. , Munshi N. , Bracy D. , Barlogie B. , Butch A.W. 
Published: October 2019

Abstract
Multiple myeloma (MM) is usually characterized by production of a single serum monoclonal protein of constant isotype and light-chain restriction. Multiple Ig isotypes and isotype switches, which are rare in untreated patients, are reported to be more common in patients undergoing myeloablative therapy. These additional protein bands, detected by immunofixation electrophoresis (IFE), could be due to altered paraprotein production by the malignant plasma cell clone or oligoclonal Ig production during recovery of B-cell function after myeloablative therapy. We analyzed abnormal protein bands (APB), distinct from the presenting paraprotein, in 550 patients receiving high-dose therapy with autologous hematopoietic cell transplantation at a single institution. Fifty-five patients (10%) had APB, 48 had oligoclonal bands (OB), and 23 had an apparent isotype switch (IS) on IFE (16 had both OB and IS). Morphologic and flow cytometric examination of bone marrow in 17 patients with IS showed no evidence of a clonal plasma cell isotype switch. Patients with APB had significantly higher complete response to therapy (67% v 37%,P = .001). To assess the independent prognostic relevance of APB, a multivariate analysis was performed among 471 patients surviving at least 12 months from first transplant (all patients developing APB had done so by 12 months from first transplant). APB (in 50 patients) was a favorable feature for both event-free (rank 3, P = .004) and overall survival (rank 3, P = .0005). We propose that OB and IS are likely to be due to recovery of Ig production rather than alterations in the biology of the malignant plasma cell clone.
Kinetics of the Graft-Versus-Leukemia Response After Donor Leukocyte Infusions for Relapsed Chronic Myeloid Leukemia After Allogeneic Bone Marrow Transplantation
Authors: Baurmann Herrad , Nagel Stefan , Binder Thomas , Neubauer Andreas , Siegert Wolfgang , Huhn Dieter 
Published: October 2019

Abstract
Little is known about the mechanisms and the kinetics of the so-called graft-versus-leukemia (GVL) response induced by donor lymphocyte infusions (DLI) in patients with leukemic relapse after allogeneic bone marrow transplantation (BMT). We sought to elucidate this problem by sequentially studying three patients with relapsed chronic myeloid leukemia after sex-mismatched BMT from time before donor leukocyte infusion until achievement of complete molecular remission. Lineage-specific chimerism was assessed longitudinally by a combined fluorescent immunophenotyping and sex chromosome-specific in situ hybridization approach. Results were related to quantitative detection of bcr-abl transcripts by competitive differential reverse transcriptase-polymerase chain reaction (RT-PCR), qualitative bcr-abl RT-PCR, and multiplex PCR-based DNA donor/recipient chimerism. All patients had predominant donor lymphopoiesis at the time of DLI, suggesting a state of tolerance to recipient leukemic and/or normal cells. In contrast, granulopoiesis and erythropoiesis were mainly recipient derived in both patients with hematologic relapse and partly recipient derived in the patient with molecular relapse. Eighty percent, 90%, and 8% of CD34+cells, respectively, were found to be of recipient origin at relapse, and few donor stem cells predicted for cytopenia post-DLI. Responses were seen after a time lag of 5 to 13 weeks after DLI and resulted in reversal to full donor chimerism within a critical switch period of 4 to 5 weeks. A sudden decrease in recipient cells was paralleled by a sharp decrease in bcr-abl transcript numbers detectable several weeks before achievement of molecular remission and onset of clinical graft-versus-host disease (GVHD). This response pattern was confirmed by retrospective RT-PCR analysis in an additional five patients. Prospective monitoring of stem cell chimerism and response may enable us to individually tailor adoptive immunotherapy in the future.