bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Metastatic Characteristics of Murine Lymphoma Cell Lines In Vivo Are Manifested After Target Organ Invasion
Authors: Aoudjit Fawzi , Potworowski Edouard F. , St-Pierre Yves 
Published: October 2019

AbstractThe ability of a tumor cell to survive is critical for successful dissemination to sites distant from the primary tumor. Tumor cells must enter blood circulation, resist hemodynamic shear stress of the blood circulation, successfully extravasate, and then migrate through dense tissue stroma to a site favorable for tumor growth. Some tumor cells must therefore be endowed with peculiar abilities to successfully metastasize, whereas others, although capable of forming tumor in specific organs, cannot metastasize. This property has often been associated with the homing ability of a given tumor cell, likely through the expression of organ-specific homing receptors that are critical for the extravasation process. The present work was aimed at establishing the point at which metastatic and nonmetastatic lymphoma cells diverge. Although 164T2 and 267T2 lymphoma cell lines can successfully form thymic lymphoma when injected intrathymically, only the 164T2 clone can efficiently form tumor in kidneys, spleen, and liver after intravenous inoculation. Using the Indium-labeling technique to monitor the homing kinetic of both cell lines, we showed that the critical step for the successful metastasis of the lymphoma cell was determined in the final steps of the disseminating process, namely after homing. These results indicate that, whereas binding of tumor cells to vascular endothelium through specific adhesion mechanisms is a prerequisite for dissemination of tumor cells, the resistance of a tumor cell to the antagonist action of the host and/or its ability to grow tumor occurs only after homing to the target organ.
Functional Characterization of L-Selectin Ligands on Human Neutrophils and Leukemia Cell Lines: Evidence for Mucinlike Ligand Activity Distinct From P-Selectin Glycoprotein Ligand-1
Authors: Ramos Carroll L. , Smith McRae J. , Snapp Karen R. , Kansas Geoffrey S. , Stickney George W. , Ley Klaus , Lawrence Michael B. 
Published: October 2019

AbstractRecent reports have shown that leukocyte-leukocyte adhesion is dependent on L-selectin and that leukocyte recognition of L-selectin may be mediated by P-selectin glycoprotein ligand-1 (PSGL-1). We show that the specific attachment and rolling of human neutrophils and the leukemia cell lines HL-60 and U937 on immobilized, purified L-selectin under continuous shear stress is only partially inhibited by treatment with the PSGL-1 monoclonal antibody (MoAb), KPL1 (41% to 53% inhibition), suggesting that L-selectin ligand activity in addition to PSGL-1 may mediate myeloid cell rolling on L-selectin. K562 cells cotransfected with cDNAs encoding α(1,3)fucosyltransferase-VII (FucT-VII) and PSGL-1 rolled on L-selectin. Adhesion of FucT-VII-PSGL-1 transfectants to L-selectin was completely blocked by MoAb KPL1, indicating that both L-selectin and P-selectin bind similar sites on PSGL-1. In support of existence of a non–PSGL-1 L-selectin ligand activity on leukocytes, an HL-60 membrane preparation immunodepleted of PSGL-1 supported rolling of L-selectin, but not P-selectin transfectants. Treatment of HL-60 cells with O-sialoglycoprotein endopeptidase inhibited attachment and rolling on L-selectin and P-selectin. However, neuraminidase treatment completely blocked HL-60 rolling on L-selectin, but not P-selectin, suggesting L-selectin and P-selectin ligand activities have different contributions of sialic acid. These findings indicate that myeloid cells express sialylated, O-linked glycoprotein ligand activity independent of PSGL-1 that supports L-selectin–mediated rolling.
Human Factor IX Corrects the Bleeding Diathesis of Mice With Hemophilia B
Authors: Kung Szu-Hao , Nathan Hagstrom J. , Cass Darrell , Jen Tai Shing , Lin Hui-Feng , Stafford Darrel W. , High Katherine A. 
Published: October 2019

AbstractMice with hemophilia B have been engineered using gene targeting techniques. These animals exhibit severe factor IX deficiency and a clinical phenotype that mirrors the human disease. We have bred the founder animals onto two different strains of mice, C57B1/6 and CD-1, and have sought to determine whether adenoviral vectors expressing human factor IX could correct the bleeding diathesis of mice with hemophilia B. Initial experiments showed that purified plasma-derived human factor IX added to murine factor IX–deficient plasma resulted in complete correction of the activated partial thromboplastin time (aPTT), and that injection of 1011 particles of an adenoviral vector expressing human factor IX resulted in normalization of a modified aPTT in mouse plasma. As an additional method of assessing the function of human factor IX in the murine coagulation system, bleeding times were performed in normal, hemophilic, and adenoviral-treated hemophilic mice. By two different bleeding-time techniques, the treated hemophilic mice gave values identical to normal littermate controls, whereas the untreated hemophilic mice exhibited heavy blood loss and prolonged bleeding. There was a marked difference in antibody formation in the two strains of mice; 100% of the hemophilic CD-1 mice formed antibodies to human factor IX, but none of the C57B1/6 mice did. These data suggest that the C57B1/6 hemophilic mice will be more useful for gene transfer studies, while the CD-1 hemophilic mice may be of greater utility in studying the development of inhibitors.
β-Chemokine Receptor CCR5 Signals Via the Novel Tyrosine Kinase RAFTK
Authors: Ganju Ramesh K. , Dutt Parmesh , Wu Lijun , Newman Walter , Avraham Hava , Avraham Shalom , Groopman Jerome E. 
Published: October 2019

AbstractChemokine receptors are coupled to G-proteins and their activation results in prominent changes in cell migration and growth. The downstream signaling pathways that mediate these effects of chemokines are largely uncharacterized. Macrophage inflammatory protein 1β (MIP 1β) binding to its cognate receptor CCR5 resulted in activation of the related adhesion focal tyrosine kinase (RAFTK), with subsequent activation of the cytoskeletal protein paxillin and the downstream transcriptional activators, c-Jun N-terminal kinase (JNK)/stress-activated protein kinase (SAPK) and p38 mitogen-activated protein (MAP) kinase. Inhibition of RAFTK by a dominant-negative kinase mutant markedly attenuated JNK/SAPK activity. Thus, RAFTK appears to provide a functional “bridge” for the transmission of CCR5 receptor signaling to the cytoskeleton and nucleus, primary sites of chemotaxis and growth regulation.
Essential Roles for Granulocyte-Macrophage Colony-Stimulating Factor (GM-CSF) and G-CSF in the Sustained Hematopoietic Response ofListeria monocytogenes–Infected Mice
Authors: Zhan Yifan , Lieschke Graham J. , Grail Dianne , Dunn Ashley R. , Cheers Christina 
Published: October 2019

AbstractThe in vivo roles of granulocyte-macrophage colony-stimulating factor (GM-CSF) and granulocyte (G)-CSF were studied in factor-deficient gene-targeted knockout mice infected with the facultative intracellular bacterium Listeria monocytogenes.Previous results showed that G-CSF−/− mice had an underlying selective deficiency in granulopoiesis, but GM-CSF−/− mice had little disturbance in resting hematopoiesis. Nevertheless, in this study it is revealed that 3 days after intraperitoneal infection with 2 × 105Listeria, GM-CSF−/− mice harbored 50-fold more organisms in their spleen and liver than similarly infected wild-type mice. This was accompanied by a severe depletion of bone marrow hematopoietic cells and a deficient inflammatory response in their peritoneal cavity. Thus, GM-CSF is essential for emergency, but not resting, hematopoiesis. In contrast, G-CSF−/− mice were markedly susceptible to low doses (2 × 104) ofListeria intraperitoneally. After infection, the acute (1 day) granulocyte infiltration to the peritoneal cavity was normal compared with wild type, but the more prolonged monocyte response was deficient, reflecting a continued decrease in bone marrow cellularity and hematopoiesis over 3 days, which was not observed in infected wild-type mice. It is thus apparent that G-CSF deficiency affects monocytopoiesis as well as granulopoiesis during infection.
Apoptosis of Malignant Human B Cells by Ligation of CD20 With Monoclonal Antibodies
Authors: Shan Daming , Ledbetter Jeffrey A. , Press Oliver W. 
Published: October 2019

AbstractCD20 is a nonglycosylated 33 to 37 kD phosphoprotein involved in B-cell signaling that subserves important functions in the regulation of B-cell proliferation and differentiation. In addition, this B-cell surface antigen has been shown recently to be an effective target for immunotherapy of B-cell malignancies using chimeric (mouse/human) or radiolabeled murine monoclonal anti-CD20 antibodies. In this report we show that extensive crosslinking of CD20 with murine anti-CD20 monoclonal antibodies (MoAbs) in the presence of either goat anti-mouse IgG or Fc receptor (FcR)-expressing cells directly inhibits B-cell proliferation, induces nuclear DNA fragmentation, and leads to cell death by apoptosis. The apoptotic effects of these MoAbs can be inhibited by chelation of extracellular or intracellular Ca2+ by EGTA or Bapta AM, indicating that anti-CD20–mediated apoptosis may be related to changes in Ca2+ concentration. These findings suggest that ligation of CD20 in vivo by anti-CD20 antibodies in the presence of FcR-expressing cells may initiate signal transduction events that induce elevation of [Ca2+]i and lead to apoptosis of malignant B cells, thereby contributing to the impressive tumor regressions observed in mouse models and clinical trials using anti-CD20 MoAbs.
Natural Killer Cell–Mediated Eradication of Neuroblastoma Metastases to Bone Marrow by Targeted Interleukin-2 Therapy
Authors: Lode Holger N. , Xiang Rong , Dreier Torsten , Varki Nissi M. , Gillies Stephen D. , Reisfeld Ralph A. 
Published: October 2019

AbstractTargeted interleukin-2 (IL-2) therapy with a genetically engineered antidisialoganglioside GD2 antibody–IL-2 fusion protein induced a cell-mediated antitumor response that effectively eradicated established bone marrow and liver metastases in a syngeneic model of neuroblastoma. The mechanism involved is exclusively natural killer (NK) cell–dependent, because NK-cell deficiency abrogated the antitumor effect. In contrast, the fusion protein remained completely effective in the T-cell–deficient mice or immunocompetent mice depleted of CD8+ T cells in vivo. A strong stimulation of NK-cell activity was also shown in vitro. Immunohistology of the leukocytic infiltrate of livers from treated mice revealed a strong staining for NK cells but not for CD8+ T cells. The therapeutic effect of the fusion protein was increased when combined with NK-cell–stimulating agents, such as poly I:C or recombinant mouse interferon-γ. In conclusion, these data show that targeted delivery of cytokines to the tumor microenvironment offers a new strategy to elicit an effective cellular immune response mediated by NK cells against metastatic neuroblastoma. This therapeutic effect may have general clinical implications for the treatment of patients with minimal residual disease who suffer from T-cell suppression after high-dose chemotherapy but are not deficient in NK cells.
Origin of the Hodgkin/Reed-Sternberg Cells in Chronic Lymphocytic Leukemia With “Hodgkin's Transformation”
Authors: Ohno Toshiyuki , Smir Bassam N. , Weisenburger Dennis D. , Gascoyne Randy D. , Hinrichs Steven D. , Chan Wing C. 
Published: October 2019

Abstract
A lymphoma with the characteristic features of Hodgkin's disease (HD) occasionally develops in patients with B-cell chronic lymphocytic leukemia (CLL), and has been called Richter's syndrome with HD features. In such cases, large tumor cells have the morphological and immunophenotypic features of classical Hodgkin and Reed-Sternberg (H-RS) cells. However, it is not known whether the H-RS cells arise from transformation of the underlying CLL cells or from a different pathological process. We report herein a study of the clonal relationship between the CLL cells and the H-RS cells in three cases of Richter's syndrome with HD features by using a single cell assay. We isolated single CLL cells and H-RS cells from immunostained tissue sections by micromanipulation. The immunoglobulin heavy chain gene (IgH) complementarity determining region (CDR) III of each cell was amplified by the polymerase chain reaction (PCR). The products were then compared by gel electrophoresis and nucleotide sequencing. The IgH CDRIII sequences from the H-RS cells were identical to those from the CLL cells in two cases. In one case, the clonal relationship between the two types of cells could not be determined because PCR products could not be obtained from any of the H-RS cells. This study shows that the H-RS cells and the CLL cells belong to the same clonal population in some cases of Richter's syndrome with HD features. Furthermore, our findings indicate that mature B cells can undergo transformation to cells with the features of H-RS cells, in association with a cellular background typical of HD. This study also supports recent findings suggesting that the H-RS cells in classical HD are derived from transformed B cells.
Inverse Targeting of Retroviral Vectors: Selective Gene Transfer in a Mixed Population of Hematopoietic and Nonhematopoietic Cells
Authors: Fielding Adele K. , Maurice Marielle , Morling Frances J. , Cosset François-Löic , Russell Stephen J. 
Published: October 2019

AbstractWe previously reported that retroviral vectors displaying epidermal growth factor (EGF) as part of a chimeric envelope glycoprotein are sequestered upon binding to EGF receptor (EGFR)-positive target cells, leading to loss of infectivity. In the current study, we have displayed stem cell factor (SCF) on β-galactosidase-transducing ecotropic and amphotropic retroviral vector particles as a factor Xa protease-cleavable N-terminal extension of the envelope glycoprotein. Viral incorporation of the SCF chimeric envelopes was demonstrated by immunoblotting of pelleted virions and their specific attachment to Kit receptors was demonstrated by flow cytometry. Gene transfer studies showed that when SCF was displayed on an amphotropic envelope, the infectivity of the SCF-displaying vectors was selectively inhibited on Kit-expressing cells, but could be restored by adding soluble SCF to block the Kit receptors or by cleaving the displayed SCF domain from the vector particles with factor Xa protease. The host range properties of EGF-displaying and SCF-displaying vectors were then compared in cell mixing experiments. When EGFR-positive cancer cells and Kit-positive hematopoietic cells were mixed and exposed to the different engineered vector particles, the cancer cells were selectively transduced by the SCF-displaying vector and the hematopoietic cells were selectively transduced by the EGF-displaying vector. Retroviral display of polypeptide growth factors can therefore provide the basis for a novel inverse targeting strategy with potential use for selective transduction of hematopoietic or nonhematopoietic cells (eg, cancer cells) in a mixed cell population.
Effect of Disease Stage on Clinical Outcome After Syngeneic Bone Marrow Transplantation for Relapsing Experimental Autoimmune Encephalomyelitis
Authors: Burt Richard K. , Padilla Josette , Begolka Wendy Smith , Canto Mauro C. Dal , Miller Stephen D. 
Published: October 2019

AbstractRelapsing experimental autoimmune encephalomyelitis (R-EAE) is an immune-mediated demyelinating central nervous system (CNS) disease. Myeloablation and syngeneic bone marrow transplantation (SBMT), when performed at the peak of acute disease (day 14), prevented glial scarring and ameliorated the disease severity. In contrast, when syngeneic BMT was performed late in chronic phase (day 78), significant glial scarring remained and the clinical severity did not differ significantly from that of the controls. After SBMT in either the acute or chronic phase of disease, the posttransplant immune system remained responsive to myelin epitopes as determined by in vitro proliferation and interferon-γ (IFN-γ) production. However, in mice undergoing SBMT, in vivo delayed-type hypersensitivity (DTH) responses were significantly decreased while IFN-γ RNA levels and inflammatory infiltrates within the CNS were slightly improved. We conclude that failure of SBMT to improve the clinical disease when performed in chronic phase may be due to preexisting glial scarring. We also conclude that in the absence of glial scarring and irreversible neuronal injury, in vivo DTH responses and histology are better predictors of clinical improvement than in vitro proliferation or IFN-γ cytokine production.
BCR-ABL Antisense Oligodeoxynucleotide In Vitro Purging and Autologous Bone Marrow Transplantation for Patients With Chronic Myelogenous Leukemia in Advanced Phase
Authors: de Fabritiis Paolo , Petti Maria Concetta , Montefusco Enrico , De Propris Maria Stefania , Sala Roberta , Bellucci Roberto , Mancini Marco , Lisci Alessandro , Bonetto Francesco , Geiser Tim , Calabretta Bruno , Mandelli Franco 
Published: October 2019

Abstract
BCR-ABL antisense oligodeoxynucleotides (ODN) have provided evidence of antileukemia effect when tested in vitro against Philadelphia-positive (Ph-pos) cells and in vivo when injected into leukemic mice. On the basis of the results obtained in vitro at diagnosis, eight patients with chronic myelogenous leukemia (CML) were selected and submitted to autologous bone marrow transplantation (ABMT) with bone marrow (BM) cells purged in vitro with junction-specific (J-sp) BCR-ABL antisense ODN at the time of transformation in accelerated phase or during second chronic phase. Mononuclear BM cells were treated in vitro for 24 or 72 hours with 150 μg/mL of antisense ODN yielding a median recovery of 47.6% mononuclear cells, 48.8% CD34+ cells, and 20.3% clonogenic cells. After a conditioning regimen including busulphan and etoposide, the reinfused treated cells allowed engraftment and hematologic reconstitution in all patients. Evaluation of the antileukemic effect by standard cytogenetic analysis and fluorescence in situ hybridization showed a complete karyotypic response in two cases and a minimal or no response in the other six. The patient autografted in second chronic phase died in blast crisis 7 months after ABMT; of the seven patients autografted in transformation, three developed blast crisis 21 to 39 months after reinfusion, one died from unrelated BMT complications 30 months after ABMT, and three are in persistent second chronic phase 14 to 26 months after autograft. The low toxicity of the protocol and the hemopoietic reconstitution observed in all patients make this approach feasible; the marked karyotypic response observed in some patients and the duration of the second chronic phase show that ODN-mediated BM purging and autograft is a promising treatment for this high-risk group of CML.
Regulation of the Erythroid Transcription Factor NF-E2 by Cyclic Adenosine Monophosphate–Dependent Protein Kinase
Authors: Casteel Darren , Suhasini Modem , Gudi Tanima , Naima Reza , Pilz Renate B. 
Published: October 2019

AbstractActivation of cyclic adenosine monophosphate (cAMP)-dependent protein kinase (A-kinase) promotes hemoglobin synthesis in several erythropoietin-dependent cell lines, whereas A-kinase–deficient murine erythroleukemia (MEL) cells show impaired hemoglobin production; A-kinase may regulate the erythroid transcription factor NF-E2 by directly phosphorylating its p45 subunit or by changing p45 interactions with other proteins. We have mapped the major A-kinase phosphorylation site of p45 to Ser169; Ala substitution for Ser169 resulted in a protein that was no longer phosphorylated by A-kinase in vitro or in vivo. The mutant protein formed NF-E2 complexes that bound to DNA with the same affinity as wild-type p45 and functioned normally to restore β-globin gene expression in a p45-deficient MEL cell line. Transactivation properties of the (Ser169 → Ala) mutant p45 were also indistinguishable from wild-type p45 when Gal4-p45 fusion constructs were tested with a Gal4-dependent reporter gene. Transactivation of the reporter by both mutant and wild-type p45 was significantly enhanced when A-kinase was activated by membrane-permeable cAMP analogs or when cells were cotransfected with the catalytic subunit of A-kinase. Stimulation of p45 transactivation by A-kinase required only the N-terminal transactivation domain of p45, suggesting that A-kinase regulates the interaction of p45 with downstream effectors.
Generation of a Primitive Erythroid Cell Line and Promotion of Its Growth by Basic Fibroblast Growth Factor
Authors: Yuen David , Mittal Leena , Deng Chu-Xia , Choi Kyunghee 
Published: October 2019

AbstractAn immortalized cell line representing the primitive erythroid (EryP) lineage was established from in vitro–differentiated progeny (embryoid bodies [EBs]) of embryonic stem (ES) cells using a retroviral insertional mutation, and has been termed EB-PE for embryoid body–derived primitive erythroid. Even though EB-PE cells are immortalized, they show characteristics of normal EryP cells, such as gene expression and growth factor dependency. In addition, EB-PE cells can differentiate further in culture. Investigation of growth factor requirements of EB-PE cells showed that basic fibroblast growth factor (bFGF) and erythropoietin (Epo) play unique roles in EB-PE proliferation and differentiation. While bFGF was a strong mitogen, Epo was required for both proliferation and differentiation. The unique proliferative response to bFGF coincided with upregulation of its receptor, fibroblast growth factor receptor (fgfr-1), and downregulation of erythropoietin receptor (EpoR) gene expression. Studies of primary EryP cells derived from early EBs, when tested in a colony-formation assay, also provided evidence for the mitogenic role of bFGF in concert with Epo.
Telomerase Activity in Candidate Stem Cells From Fetal Liver and Adult Bone Marrow
Authors: Yui Jane , Chiu Choy-Pik , Lansdorp Peter M. 
Published: October 2019

AbstractTelomerase is a ribonucleoprotein polymerase that synthesizes telomeric repeats onto the 3′ ends of eukaryotic chromosomes. Activation of telomerase may prevent telomeric shortening and correlates with cell immortality in the germline and certain tumor cells. Candidate hematopoietic stem cells (HSC) from adult bone marrow express low levels of telomerase, which is upregulated with proliferation and/or differentiation. To address this issue, we stimulated purified candidate HSC from human adult bone marrow with stem cell factor (SCF), interleukin-3 (IL-3), and Flt3-ligand (FL). After 5 days in culture, activity was detected in total cell extracts from IL-3–, SCF + FL–, SCF + IL-3–, FL + IL-3–, and SCF + IL-3 + FL–stimulated cultures, but not from cells cultured in SCF or FL alone. Within the CD34+fraction of the cultured cells, significant activity was found in the CD34+CD71+ fraction. In addition, PKH26 staining confirmed that detectable telomerase activity was present in dividing PKH26lo cells, whereas nondividing PKH26hi cells were telomerase negative. Because in these experiments no distinction could be made between cycling “candidate” stem cells that had retained or had lost self-renewal properties, fetal liver cells with a CD34+CD38− phenotype, highly enriched for cycling stem cells, were also examined and found to express readily detectable levels of telomerase activity. Given the replication-dependent loss of telomeric DNA in hematopoietic cells, these observations suggest that the observed telomerase activity in candidate stem cells is either expressed in a minor subset of stem cells or, more likely, is not sufficient to prevent telomere shortening.