bluuebunny/crossref_metadata_2025_split huggingface dataset:
Granulocyte-macrophage colony-stimulating factor, interleukin-3 (IL-3), and IL-5 greatly enhance the interaction of human eosinophils with opsonized particles by changing the affinity of complement receptor type 3
Authors: Blom M , Tool AT , Kok PT , Koenderman L , Roos D , Verhoeven AJ 
Published: October 2019

Abstract
Eosinophil functions can be modulated by several cytokines such as granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin- 3 (IL-3), and IL-5. We have investigated the modulatory role of these cytokines on the interaction of human eosinophils with opsonized particles (serum-treated zymosan [STZ]). Addition of STZ to eosinophils isolated from the peripheral blood of normal human donors resulted in an interaction of the STZ particles with only 15% to 25% of the cells. Treatment of the eosinophils with GM-CSF, IL-3, or IL-5 strongly enhanced both the rate of particle binding and the percentage of eosinophils binding STZ. The effect of the cytokines is most likely mediated by a change in affinity of the complement receptor type 3 (CR3) on the eosinophils for the complement fragment iC3b on the STZ particles. This is indicated by the observation that (1) the effect of the cytokines on STZ binding was prevented by a monoclonal antibody against the iC3b-binding site on CR3 and (2) the enhanced binding was already apparent before upregulation of CR3 on the cell surface was observed. In a previous study, similar results were obtained with platelet-activating factor (PAF)-primed eosinophils. Because we found that the cytokines strongly enhanced the STZ-induced PAF synthesis, we investigated the role of both released PAF and cell-associated PAF in the priming phenomenon by the cytokines. Cytokine priming appeared to be largely independent of the synthesis of PAF.
Regulation by interleukin-2 (IL-2) and interferon gamma of IL-2 receptor gamma chain gene expression in human monocytes
Authors: Bosco MC , Espinoza-Delgado I , Schwabe M , Gusella GL , Longo DL , Sugamura K , Varesio L 
Published: October 2019

Abstract
The interleukin-2 receptor gamma chain (IL-2R gamma) gene codes for a subunit of the IL-2R and is expressed in human lymphoid cells. The present study was undertaken to determine whether human monocytes expressed the IL-2R gamma gene constitutively or after activation by IL- 2 or interferon gamma (IFN gamma). Fresh human monocytes constitutively expressed low but significant levels of IL-2R gamma mRNA, and nuclear run-on experiments showed that IL-2R gamma gene was transcriptionally active. Stimulation with IL-2 or IFN gamma induced a major increase of IL-2R gamma mRNA in a time- and a dose-dependent manner. However, neither cytokine increased the transcriptional activity of the gene. The enhancement of IL-2R gamma mRNA expression by either IL-2 or IFN gamma was concomitant with the stabilization of the mRNA, suggesting a postranscriptional level of control. Finally, the augmented expression of IL-2R gamma in IL-2- and IFN gamma-treated monocytes was associated with an increased IL-2-binding activity, compared with that of unstimulated cells. These results provide the first evidence of the expression of the IL-2R gamma gene in nonlymphoid cells and of its modulation by IL-2 and IFN gamma through posttranscriptional mechanisms.
Persistence of host-type hematopoiesis after allogeneic bone marrow transplantation for leukemia is significantly related to the recipient's age and/or the conditioning regimen, but it is not associated with an increased risk of relapse
Authors: van Leeuwen JE , van Tol MJ , Joosten AM , Wijnen JT , Verweij PJ , Khan PM , Vossen JM 
Published: October 2019

Abstract
We investigated the chimerism pattern within flow-sorted peripheral blood- or bone marrow-derived cell populations after allogeneic bone marrow transplantation (BMT) for the treatment of leukemia in children. This study was performed to define the identity of persistent host-type cells, to identify prognostic variables for the persistence of host- type hematopoiesis, and to determine the prognostic significance of the chimerism pattern on the duration of the leukemia-free interval, the overall survival, and the leukemia-free survival. The patients received either HLA-identical non-T-cell-depleted (n = 46) or HLA nonidentical T- cell-depleted (n = 7) BMT. In the peripheral blood, the children showed either stable mixed chimerism (SMC; ie, persistent host-type hematopoiesis; n = 14), (transient) mixed T-lymphoid chimerism (MTLC; n = 9), or complete chimerism (CC; n = 30). In the bone marrow, only donor-type cells were found in children with either CC (n = 8) or MTLC (n = 2), and a mixture of donor- and recipient-type cells was found in children with SMC (n = 7). The persistence of host-type hematopoiesis (SMC) was significantly related to a lower age of the recipient, the type of conditioning regimen, a lower total body irradiation dose, T- cell depletion of the bone marrow graft, and the use of cyclosporine A for acute graft-versus-host disease prophylaxis. No significant differences were found between patients with (SMC) or without (CC/MTLC) persistent host-type hematopoiesis with respect to the duration of the leukemia-free interval, the overall survival, or the leukemia-free survival. We conclude that ablation of host-type hematopoiesis is not compulsory for long-term leukemia-free survival after allogeneic BMT for various hematologic malignancies.
Unrelated donor or autologous marrow transplantation for treatment of acute leukemia
Authors: Busca A , Anasetti C , Anderson G , Appelbaum FR , Buckner CD , Doney K , Martin PJ , Petersdorf E , Sanders JE , Hansen JA 
Published: October 2019

Abstract
High-dose chemoradiotherapy followed by marrow transplantation from an HLA-matched sibling donor is curative for patients with acute leukemia. Autologous marrow transplantation has been used with success for some patients without such a sibling. Alternatively, the option of performing a transplant from an HLA-matched unrelated donor has been made possible by the recent development of large registries of HLA- typed volunteers. The purpose of this study was to compare the outcomes for patients with advanced leukemia treated by unrelated or autologous marrow transplantation. Forty-three patients with acute myeloid or lymphoid leukemia were transplanted from a closely HLA-matched unrelated donor. Results were compared with those of a disease-, disease-stage-, and age-matched cohort of 77 patients treated with autologous marrow transplantation at the same institution during the same period. Myeloid reconstitution with peripheral granulocyte counts greater than 10(9)/L was achieved in 93% of unrelated recipients and 70% of autologous recipients at a median of 24 and 36 days after transplantation, respectively (P = .0001). The cumulative proportions of patients discharged alive (79% v 77%) and times from transplant to first hospital discharge (35 v 34 days) were not different between unrelated and autologous recipients (P = .65). For patients transplanted in complete remission, relapse occurred after transplantation in 27% of the unrelated and in 55% of the autologous recipients (P = .08). For patients transplanted in relapse, the corresponding posttransplant relapse rates were 48% and 63%, respectively (P = .72). Forty percent of unrelated recipients and 28% of autologous recipients died in remission. Leukemia-free survivals were 33% for unrelated and 25% for autologous recipients transplanted in remission (P = .45), and 12% for unrelated and 5% for autologous recipients transplanted in relapse (P = .75). Unrelated donor transplants appear no less effective than autologous transplants to achieve long-term survival and may be more effective in eradicating leukemia in patients who have failed conventional chemotherapy. Further studies are warranted to assess the relative effectiveness of unrelated and autologous transplantation performed earlier in the course of the disease.
Primitive Human Hematopoietic Cells Are Enriched in Cord Blood Compared With Adult Bone Marrow or Mobilized Peripheral Blood as Measured by the Quantitative In Vivo SCID-Repopulating Cell Assay
Authors: Wang Jean C.Y. , Doedens Monica , Dick John E. 
Published: October 2019

AbstractWe have previously reported the development of in vivo functional assays for primitive human hematopoietic cells based on their ability to repopulate the bone marrow (BM) of severe combined immunodeficient (SCID) and nonobese diabetic/SCID (NOD/SCID) mice following intravenous transplantation. Accumulated data from gene marking and cell purification experiments indicate that the engrafting cells (defined as SCID-repopulating cells or SRC) are biologically distinct from and more primitive than most cells that can be assayed in vitro. Here we demonstrate through limiting dilution analysis that the NOD/SCID xenotransplant model provides a quantitative assay for SRC. Using this assay, the frequency of SRC in cord blood (CB) was found to be 1 in 9.3 × 105 cells. This was significantly higher than the frequency of 1 SRC in 3.0 × 106 adult BM cells or 1 in 6.0 × 106 mobilized peripheral blood (PB) cells from normal donors. Mice transplanted with limiting numbers of SRC were engrafted with both lymphoid and multilineage myeloid human cells. This functional assay is currently the only available method for quantitative analysis of human hematopoietic cells with repopulating capacity. Both CB and mobilized PB are increasingly being used as alternative sources of hematopoietic stem cells in allogeneic transplantation. Thus, the findings reported here will have important clinical as well as biologic implications.
Cytokine Treatment of Endothelial Cells Increases Glycoprotein Ibα-Dependent Adhesion to von Willebrand Factor
Authors: Beacham Dorothy A. , Tran Linh-Phuong , Shapiro Sandor S. 
Published: October 2019

AbstractEndothelial cells (EC) possess at least two membrane receptors for von Willebrand factor (vWF ), the vitronectin receptor (VNR, αvβ3 ), which recognizes an Arg-Gly-Asp (RGD) sequence in the C-terminus of vWF, and glycoprotein Ibα (GP Ibα), which interacts with a region in the N-terminal A1 domain of vWF. In the absence of added cytokines, EC attachment to a vWF substratum is mediated largely through the αvβ3 , with a smaller contribution by GP Ibα. In the present study, we have examined the effect of cytokines on the receptor specificity of EC attachment to wild-type vWF (WT-vWF ) and to vWF, which had been mutated in the C-terminal RGDS sequence (RADS-vWF ). Exposure of human umbilical vein EC (HUVEC) to tumor necrosis factor-α (TNF-α) or to TNF-α in combination with interferon-γ (IFN-γ), but not to interleukin-1β (IL-1), increased attachment to RADS-vWF by about twofold. The TNF-α–induced increase in EC attachment was accompanied by an increase in cell surface GP Ibα expression; GP Ibα surface expression was not increased by IL-1. Attachment of untreated HUVEC to WT-vWF could be inhibited 60% to 70% by a monoclonal antibody (MoAb) (LM609) to the VNR and 30% to 40% by the A1 fragment of vWF (containing the GP Ibα binding domain). The pattern of inhibition of attachment to WT-vWF was largely unchanged after TNF-α treatment of HUVEC. In contrast, the attachment to WT-vWF of HUVEC, treated with TNF-α +IFN-γ was completely inhibited by vWF-A1 and inhibited only 35% by the anti-VNR antibody LM609. Two MoAbs to GP Ibα produced similar, but incomplete, inhibition. Pretreatment of HUVEC with the combination of TNF-α +IFN-γ produced a dramatic decrease in VNR expression, confirming previous findings of Defilippi et al. These results suggest that in the presence of the inflammatory cytokines TNF-α +IFN-γ, the endothelial GP Ib complex is a major determinant of HUVEC adhesion to surface-bound vWF.
Control of Cell Cycle Progression in Human Natural Killer Cells Through Redox Regulation of Expression and Phosphorylation of Retinoblastoma Gene Product Protein
Authors: Yamauchi Akira , Bloom Eda T. 
Published: October 2019

AbstractUsing thiol deprivation, we have previously shown that the response of natural killer (NK) cells to interleukin-2 (IL-2) is subject to redox regulation downstream of IL-2 binding and internalization. We have now used the IL-2–dependent cell line, NK3.3 to study redox regulation of NK cells further, and found that NK3.3 cells neither incorporated [3H]-thymidine nor completed the G1-S phase transition in medium lacking the thiol-related compounds, L-cystine, and glutathione, despite the presence of sufficient IL-2. Thiol deprivation did not alter the induction of DNA interferon-γ activated sequence (GAS)-binding activity in response to IL-2. However, the retinoblastoma gene product (RB), a cyclin-dependent kinase (CDK) substrate, was phosphorylated within 24 hours after IL-2 stimulation in standard medium, but its expression and phosphorylation were reduced in thiol-depleted medium in both NK3.3 cells and freshly isolated NK cells. These reductions were not associated with an increased level of p27Kip1, an inhibitor of CDKs CDK6/2 in association with G1 cyclins. Reducing agents, N-acetylcysteine, reduced glutathione or 2-ME restored both RB phosphorylation and DNA synthesis in thiol-deprived NK3.3 cells. The in vitro kinase activities of CDK6 and CDK2 were prematurely increased by thiol deprivation. This enhancement was associated with CDK hyperphosphorylation and prolonged phosphorylation, and could be observed before and beyond IL-2 stimulation. The data suggest the possibility that the premature and prolonged enhancement of CDK activity in thiol-deprived NK cells is associated with, and therefore may contribute to, the reduced expression and phosphorylation of RB, and the associated cell cycle arrest.
Augmented Intracellular Glutathione Inhibits Fas-Triggered Apoptosis of Activated Human Neutrophils
Authors: Watson R. William G. , Rotstein Ori D. , Jimenez Maria , Parodo Jean , Marshall John C. 
Published: October 2019

AbstractAgonist signals delivered through cell surface Fas induce apoptosis. However, the apoptotic program can be modulated by signals from the environment, and in particular, by signals delivered through adhesion molecules. Because neutrophil functional activity in inflammation is contingent on cell survival, and because circulating neutrophils normally die rapidly through a constitutively expressed apoptotic program, we evaluated Fas-mediated apoptosis in resting and inflammatory human neutrophils. We show that normal neutrophils respond to Fas engagement with accelerated rates of apoptosis, but cross-linking of β2 integrins or priming with bacterial lipopolysaccharide (LPS) prevents this increase. Adhesion molecule cross-linking results in increased intracellular glutathione (GSH). Augmentation of intracellular GSH with exogenous GSH or N-acetylcysteine is sufficient to reduce the Fas-triggered increase in apoptotic rates. Prevention of the activation induced GSH increase by buthionine sulfoximine, a cell permeable inhibitor of GSH biosynthesis, restored Fas responsiveness in activated neutrophils, an effect that could be blocked with exogenous GSH. Taken together, these data show that Fas-induced signaling for neutrophil apoptosis is blocked in a redox sensitive manner by costimulatory signals delivered through β2 integrins or activation by LPS, and provide a biologic explanation for sustained neutrophil survival in the inflammatory environment.
Fibronectin Enhances In Vitro Lipopolysaccharide Priming of Polymorphonuclear Leukocytes
Authors: Bortolussi Robert , Rajaraman Kausalya , Qing Gefei , Rajaraman Rengaswami 
Published: October 2019

AbstractWe investigated the role of humoral factors in lipopolysaccharide (LPS) priming of polymorphonuclear leukocytes (PMN) using cells isolated from adults and from neonates. Plasma from newborn infants had decreased priming activity of adult plasma when mixed with LPS in studies measuring oxidative radical production of PMN after stimulation with a formyl bacterial oligopeptide (fMLP). This marked difference was not caused by LPS binding protein (LBP) because the LBP concentration in newborn and adult plasma were similar (138.4 ± 12.9 U for adults, and 126.9 ± 12.1 U for neonates, P = .53). Therefore, we attempted to identify other plasma factors that may contribute to LPS priming of PMN. We identified an LPS priming factor for PMN that is present in plasma, heat stable (56°C for 30 minutes), enhanced by heparin, and concentrated in cold precipitates of plasma. Because these properties resemble those of plasma fibronectin, we assessed the role of fibronectin in LPS priming of PMN. Although fibronectin in phosphate-buffered saline (PBS) had little effect on LPS priming of PMN, fibronectin in combination with other plasma factors appeared to play a role in LPS priming of PMN because (1) removing fibronectin from adult plasma dramatically decreased LPS priming activity from plasma (P < .005), (2) addition of fibronectin to fibronectin-depleted plasma restored its LPS plasma priming activity (P < .05), and (3) neutralizing fibronectin with antibody decreased the LPS priming activity of plasma (60.3 ± 1.3 v 30.2 ± 2.2, P < .01). Thus, plasma fibronectin plays a role in LPS priming of PMN in the presence of other factors in plasma.
A Retinoid-Resistant Acute Promyelocytic Leukemia Subclone Expresses a Dominant Negative PML-RARα Mutation
Authors: Shao Wenlin , Benedetti Laura , Lamph William W. , Nervi Clara , Miller Wilson H. 
Published: October 2019

Abstract
The unique t(15; 17) of acute promyelocytic leukemia (APL) fuses the PML gene with the retinoic acid receptor α (RARα) gene. Although retinoic acid (RA) inhibits cell growth and induces differentiation in human APL cells, resistance to RA develops both in vitro and in patients. We have developed RA-resistant subclones of the human APL cell line, NB4, whose nuclear extracts display altered RA binding. In the RA-resistant subclone, R4, we find an absence of ligand binding of PML-RARα associated with a point mutation changing a leucine to proline in the ligand-binding domain of the fusion PML-RARα protein. In contrast to mutations in RARα found in retinoid-resistant HL60 cells, in this NB4 subclone, the coexpressed RARα remains wild-type. In vitro expression of a cloned PML-RARα with the observed mutation in R4 confirms that this amino acid change causes the loss of ligand binding, but the mutant PML-RARα protein retains the ability to heterodimerize with RXRα and thus to bind to retinoid response elements (RAREs). This leads to a dominant negative block of transcription from RAREs that is dose-dependent and not relieved by RA. An unrearranged RARα engineered with this mutation also lost ligand binding and inhibited transcription in a dominant negative manner. We then found that the mutant PML-RARα selectively alters regulation of gene expression in the R4 cell line. R4 cells have lost retinoid-regulation of RXRα and RARβ and the RA-induced loss of PML-RARα protein seen in NB4 cells, but retain retinoid-induction of CD18 and CD38. Thus, the R4 cell line provides data supporting the presence of an RARα-mediated pathway that is independent from gene expression induced or repressed by PML-RARα. The high level of retinoid resistance in vitro and in vivo of cells from some relapsed APL patients suggests similar molecular changes may occur clinically.
Defensin Stimulates the Binding of Lipoprotein (a) to Human Vascular Endothelial and Smooth Muscle Cells
Authors: Higazi Abd Al-Roof , Lavi Ehud , Bdeir Khalil , Ulrich Anthony M. , Jamieson Dara G. , Rader Daniel J. , Usher David C. , Kane William , Ganz Tomas , Cines Douglas B. 
Published: October 2019

AbstractThere is evidence to suggest that elevated plasma levels of lipoprotein (a) [Lp(a)] represent a risk factor for the development of atherosclerotic vascular disease, but the mechanism by which this lipoprotein localizes to involved vessels is only partially understood. In view of studies suggesting a link between inflammation and atherosclerosis and our previous finding that leukocyte defensin modulates the interaction of plasminogen and tissue-type plasminogen activator with cultured human endothelial cells, we examined the effect of this peptide on the binding of Lp(a) to cultured vascular endothelium and vascular smooth muscle cells. Defensin increased the binding of Lp(a) to endothelial cells approximately fourfold and to smooth muscle cells approximately sixfold. Defensin caused a comparable increase in the amount of Lp(a) internalized by each cell type, but Lp(a) internalized as a consequence of defensin being present was not degraded, resulting in a marked increase in the total amount of cell-associated lipoprotein. Abundant defensin was found in endothelium and in intimal smooth muscle cells of atherosclerotic human cerebral arteries, regions also invested with Lp(a). These studies suggest that defensin released from activated or senescent neutrophils may contribute to the localization and persistence of Lp(a) in human vessels and thereby predispose to the development of atherosclerosis.
Kinetic Evidence of the Regeneration of Multilineage Hematopoiesis From Primitive Cells in Normal Human Bone Marrow Transplanted Into Immunodeficient Mice
Authors: Cashman Johanne D. , Lapidot Tsvee , Wang Jean C.Y. , Doedens Monica , Shultz Leonard D. , Lansdorp Peter , Dick John E. , Eaves Connie J. 
Published: October 2019

AbstractBased on initial observations of human CD34+ Thy-1+ cells and long-term culture-initiating cells (LTC-IC) in the bone marrow of some sublethally irradiated severe combined immunodeficient (SCID) mice transplanted intravenously with normal human marrow cells, and the subsequent finding that the NOD/LtSz-scid/scid (NOD/SCID) mouse supports higher levels of human cell engraftment, we undertook a series of time course experiments to examine posttransplant changes in the number, tissue distribution, cycling activity, and in vivo differentiation pattern of various human hematopoietic progenitor cell populations in this latter mouse model. These studies showed typical rapid posttransplant recovery curves for human CD34− CD19+ (B-lineage) cells, CD34+ granulopoietic, erythroid, and multilineage colony-forming cells (CFC), LTC-IC, and CD34+ Thy-1+ cells from a small initial population representing <0.1% of the original transplant. The most primitive human cell populations reached maximum values at 5 weeks posttransplant, after which they declined. More mature cell types peaked after another 5 weeks and then declined. A 2-week course of thrice weekly injections of human Steel factor, interleukin (IL)-3, granulocyte-macrophage colony-stimulating factor (GM-CSF), and erythropoietin (administered just before the mice were killed for analysis) did not alter the pace of regeneration of either primitive or mature human hematopoietic cells, or their predominantly granulopoietic and B-lymphoid pattern of differentiation, although a significant enhancing effect on the level of human cell engraftment sustained after 3 months was noted. Cycling studies showed the human CFC present at 4 to 5 weeks posttransplant to be rapidly proliferating even in mice not given human growth factors. However, by 10 weeks and thereafter, only quiescent human CFC were detected; interestingly, even in mice that were given the 2-week course of growth factor injections. These studies indicate the use of this model for future analysis of the properties and in vivo regulation of primitive human hematopoietic cells that possess in vivo repopulating ability.