bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Glycoprotein Ib/IX Complex Regulates Cell Proliferation
Authors: Feng Shuju , Christodoulides Nicolaos , Kroll Michael H. 
Published: October 2019

AbstractThe glycoprotein (Gp) Ib/IX complex contains three transmembranous leucine-rich repeat polypeptides (GpIb, GpIbβ, and GpIX) that form the platelet von Willebrand factor (vWF) receptor. GpIb/IX functions to effect platelet adhesion, activation, and aggregation under conditions of high shear stress. GpIb/IX is expressed late in the ontogeny of megakaryocytes, the precursor cell that releases platelets when it reaches its terminal stage of differentiation. Because signal pathways can be reused at different stages of development by integration with different effector pathways and because cellular adhesion through other receptor families often modulates cell growth, the hypothesis that GpIb/IX regulates cell growth was investigated. The surface expression of recombinant GpIb decreases the proliferation of transduced CHO cells. GpIb causes growth arrest in the G1 phase of the cell cycle associated with the induction of the cyclin-dependent kinase inhibitor p21. G1 arrest induced by recombinant GpIb in heterologous cells requires signaling through the 14-3-3ζ binding domain of GpIb and is partially dependent on its engagement by the extracellular ligand vWF. Growth arrest induced by the expression of recombinant GpIb/IX is followed by apoptosis of the transduced cells. The endogenous expression of GpIb in human hematopoietic cells is associated with decreased proliferation. These results suggest that the expression of the GpIb/IX complex regulates megakaryocyte growth.
Hypermethylation of the DAP-Kinase CpG Island Is a Common Alteration in B-Cell Malignancies
Authors: Katzenellenbogen Rachel A. , Baylin Stephen B. , Herman James G. 
Published: October 2019

Abstract
Death-associated protein kinase (DAP-Kinase) is a novel serine/threonine kinase whose expression is required for γ interferon-induced apoptosis. A previous study suggested that DAP-Kinase expression may be lost epigenetically in cancer cell lines, because treatment of several nonexpressing cell lines with 5-aza-2′-deoxycytidine resulted in the expression of DAP-Kinase. Using methylation-specific polymerase chain reaction (MSP), we examined the DAP-Kinase CpG island for hypermethylation in cancer. Normal lymphocytes and lymphoblastoid cell lines are unmethylated in the 5′ CpG island of DAP-Kinase. However, in primary tumor samples, all Burkitt’s lymphomas and 84% of the B-cell non-Hodgkin’s lymphomas were hypermethylated in the DAP-Kinase CpG island. In contrast, none of the T-cell non-Hodgkin’s lymphoma samples and 15% or less of leukemia samples examined had hypermethylated DAP-Kinase alleles. U937, an unmethylated, DAP-Kinase–expressing leukemia cell line, was treated with γ interferon and underwent apoptosis; however, Raji, a fully methylated, DAP-Kinase nonexpressing Burkitt’s lymphoma cell line, only did so when treated with 5-aza-2′-deoxycytidine followed by γ interferon. Our findings in cell lines and primary tumors suggest that hypermethylation of the DAP-Kinase gene and loss of γ interferon-mediated apoptosis may be important in the development of B-cell malignancies and may provide a promising biomarker for B-cell–lineage lymphomas.
Lineage-Specific Modulation of Calcium Pump Expression During Myeloid Differentiation
Authors: Launay Sophie , Giannı̀ Maurizio , Kovàcs Tünde , Bredoux Raymonde , Bruel Arlette , Gélébart Pascal , Zassadowski Fabien , Chomienne Christine , Enouf Jocelyne , Papp Béla 
Published: October 2019

AbstractCalcium is accumulated from the cytosol into the endoplasmic reticulum by sarco-endoplasmic reticulum calcium transport ATPase (SERCA) enzymes. Because calcium stored in the endoplasmic reticulum is essential for cell growth, differentiation, calcium signaling, and apoptosis and because different SERCA enzymes possess distinct functional characteristics, in the present report we explored SERCA expression during in vitro differentiation of the human myeloid/promyelocytic cell lines HL-60 and NB4 and of freshly isolated acute promyelocytic leukemia cells. Two SERCA species have been found to be coexpressed in these cells: SERCA 2b and another isoform, SERCAPLIM, which is recognized by the PLIM430 monoclonal antibody. Induction of differentiation along the neutrophil granulocytic lineage by all-trans retinoic acid or cyclic AMP analogs led to an increased expression of SERCAPLIM, whereas the expression of the SERCA 2b isoform was decreased. The modulation of SERCA expression was manifest also on the mRNA level. Experiments with retinoic acid receptor isoform-specific retinoids indicated that SERCA expression is modulated by retinoic acid receptor -dependent signaling. SERCA expression of retinoic acid-resistant cell variants was refractory to treatment. Differentiation along the monocyte/macrophage lineage by phorbol ester resulted in an increased expression of both SERCA isoforms. In addition, when cells were treated by phorbol ester in the presence of the glucocorticoid dexamethasone, a known inhibitor of monocyte differentiation, a selective blockage of the induction of SERCAPLIM was observed. Altered SERCA expression modified the functional characteristics of calcium transport into the endoplasmic reticulum. These observations show for the first time that the modulation of calcium pump expression is an integral component of the differentiation program of myeloid precursors and indicate that a lineage-specific remodelling of the endoplasmic reticulum occurs during cell maturation. In addition, these data show that SERCA isoforms may serve as useful markers for the study of myeloid differentiation.
The Expression of Human Blood Group Antigens During Erythropoiesis in a Cell Culture System
Authors: Southcott Mark J.G. , Tanner Michael J.A. , Anstee David J. 
Published: October 2019

AbstractPhenotypic analysis of hematopoietic stem and progenitor cells has been an invaluable tool in defining the biology of stem cell populations. We use here flow cytometry to examine the expression of human erythroid-specific surface markers during the maturation of early committed erythroid cells derived from cord blood in vitro. The temporal order of the expression of erythroid specific markers was as follows: Kell glycoprotein (gp), Rh gp, Landsteiner Wiener (LW) gp, glycophorin A (GPA), Band 3, Lutheran (Lu) gp, and Duffy (Fy) gp. The time at which some of these markers appeared suggests possible roles for some of these erythroid-specific polypeptides during the differentiation of these committed progenitors. The early appearance of Kell gp raises the possibility that it may have an important role in the early stages of hematopoiesis or cell lineage determination. Kell gp may also be a useful marker for the diagnosis of erythroleukemia. The late expression of Lu gp suggests it may be involved in the migration of erythroid precursors from the marrow. Fy gp is also expressed late consistent with a role as a scavenger receptor for cytokines in the bone marrow and circulation. Rh c antigen appeared before Rh D antigen, and it is suggested that this may reflect a reorganization of the developing erythroid cell membrane involving the Rh polypeptides and other components, including GPA and Band 3.
Defective Internalization and Sustained Activation of Truncated Granulocyte Colony-Stimulating Factor Receptor Found in Severe Congenital Neutropenia/Acute Myeloid Leukemia
Authors: Ward Alister C. , van Aesch Yvette M. , Schelen Anita M. , Touw Ivo P. 
Published: October 2019

AbstractAcquired mutations truncating the C-terminal domain of the granulocyte colony-stimulating factor receptor (G-CSF-R) are found in about 20% of severe congenital neutropenia (SCN) patients, with this cohort of patients predisposed to acute myeloid leukemia (AML). In myeloid cells, such mutations act in a dominant-negative manner leading to hyperproliferation and lack of differentiation in response to G-CSF. However, why these truncated receptors are dominant in function over wild-type receptors has remained unclear. We report that ligand-induced internalization of truncated G-CSF-R is severely impaired compared with the wild-type receptor, which results in sustained activation of STAT proteins. Strikingly, in cells coexpressing both truncated and wild-type forms, the truncated receptors acted dominantly with regard to both internalization and sustained activation. Site-directed mutagenesis of the C-terminus showed that receptor tyrosines in this region were dispensable for internalization, whereas a di-leucine–containing motif in Box B3 played some role. However, loss of the di-leucine motif was not the critical determinant of the sustained activation status of truncated receptors. These data suggest that defective internalization, leading to extended receptor activation, is a major cause of the dominant hyperproliferative effect of truncated G-CSF receptors, which is only partially due to the loss of a di-leucine motif present in the Box B3 region of the full-length receptor.
Comparison of Immune Reconstitution After Unrelated and Related T-Cell–Depleted Bone Marrow Transplantation: Effect of Patient Age and Donor Leukocyte Infusions
Authors: Small T.N. , Papadopoulos E.B. , Boulad F. , Black P. , Castro-Malaspina H. , Childs B.H. , Collins N. , Gillio A. , George D. , Jakubowski A. , Heller G. , Fazzari M. , Kernan N. , MacKinnon S. , Szabolcs P. , Young J.W. , O’Reilly R.J. 
Published: October 2019

Abstract
Unrelated bone marrow transplantation (BMT) is often complicated by fatal opportunistic infections. To evaluate features unique to immune reconstitution after unrelated BMT, the lymphoid phenotype, in vitro function, and life-threatening opportunistic infections after unrelated and related T-cell–depleted (TCD) BMT were analyzed longitudinally and compared. The effects of posttransplant donor leukocyte infusions to treat or prevent cytomegalovirus (CMV) or Epstein-Barr virus (EBV) infections on immune reconstitution were also analyzed. This study demonstrates that adult recipients of TCD unrelated BMTs experience prolonged and profound deficiencies of CD3+, CD4+, and CD8+ T-cell populations when compared with pediatric recipients of unrelated BMT and adults after related BMT (P &lt; .01), that these adults have a significantly increased risk of life-threatening opportunistic infections, and that the rate of recovery of CD4 T cells correlates with the risk of developing these infections. Recovery of normal numbers of CD3+, CD8+, and CD4+ T-cell populations is similar in children after related or unrelated BMT. This study also demonstrates that adoptive immunotherapy with small numbers of unirradiated donor leukocytes can be associated with rapid restoration of CD3+, CD4+, and CD8+T-cell numbers, antigen-specific T-cell responses, and resolution of CMV- and EBV-associated disease after unrelated TCD BMT.
Selective Requirements for Leukocyte Adhesion Molecules in Models of Acute and Chronic Cutaneous Inflammation: Participation of E- and P- But Not L-Selectin
Authors: Catalina Michelle D. , Estess Pila , Siegelman Mark H. 
Published: October 2019

AbstractAdhesion molecules borne by both endothelial cells and circulating leukocytes are in large measure responsible for guiding the process of extravasation. The selectin family has been primarily associated with the early stages of adhesion involving initial contact and rolling. A significant body of evidence has accumulated indicating a fundamental role for the endothelial members of this family, E- and P-selectin, in a variety of inflammatory states and models. Although originally identified as the lymph node-specific lymphocyte homing receptor, L-selectin has also been suggested to play an important role in leukocyte recruitment to sites of inflammation. We have recently demonstrated, using L-selectin–deficient mice, that defects in contact hypersensitivity (CHS) responses are in essence due to the inability of T cells to home to and be sensitized within peripheral lymph nodes, whereas nonspecific effector cells are fully capable of entry into sites of cutaneous inflammation (Catalina et al, J Exp Med184:2341, 1996). In the present study, we perform an analysis of adhesion molecule usage in two models of skin inflammation and show in both L-selectin–deficient as well as wild-type mice that a combination of P- and E-selectin is crucial for the development of both acute (croton oil) and chronic (contact hypersensitivity) inflammation at sites of the skin, whereas L-selectin does not appear to play a significant role. Moreover, 4 integrins are shown to be integral to a CHS but not an acute irritant response, whereas CD44 does not significantly contribute to either. These results provide a systematic examination in one study of major adhesion molecules that are critical in acute and chronic skin inflammation. They reinforce the essential role of the collaboration of E- and P-selectin in both specific and nonspecific skin inflammatory responses and the importance of 4 in the specific response only. In addition, they substantiate only a limited role, if any, for L-selectin in these cutaneous effector mechanisms and demonstrate the essential equivalence in this analysis of L-selectin–deficient mice compared with normal mice treated with blocking antibodies.
Detection of Normal and Chimeric Nucleophosmin in Human Cells
Authors: Cordell Jacqueline L. , Pulford Karen A.F. , Bigerna Barbara , Roncador Giovanna , Banham Alison , Colombo Emanuela , Pelicci Pier-Giuseppe , Mason David Y. , Falini Brunangelo 
Published: October 2019

AbstractIn anaplastic large-cell lymphoma (ALCL), the (2;5) chromosomal translocation creates a fusion gene encoding the 80-kD NPM-ALK hybrid protein. This report describes three new monoclonal antibodies, two of which recognize, by Western blotting, the N-terminal portion of NPM present in the NPM-ALK fusion protein and also in two other NPM fusion proteins (NPM-RAR and NPM-MLF1). The third antibody recognizes the C-terminal portion (deleted in NPM-ALK) and reacts only with wild-type NPM. The three antibodies immunostain wild-type NPM (in paraffin-embedded normal tissue samples) in cell nuclei and in the cytoplasm of mitotic cells. Cerebral neurones, exceptionally, show diffuse cytoplasmic labeling. In contrast to normal tissues, the two antibodies against the N-terminal portion of NPM labeled the cytoplasm of neoplastic cells, in four ALK-positive ALCL, reflecting their reactivity with NPM-ALK fusion protein, whereas the antibody to the C-terminal NPM epitope labeled only cell nuclei. Immunocytochemical labeling with these antibodies can therefore confirm that an ALK-positive lymphoma expresses NPM-ALK (rather than a variant ALK-fusion protein) and may also provide evidence for chromosomal anomalies involving the NPM gene other than the classical (2;5) translocation.
Eradication of Pre-Established Lymphoma Using Herpes Simplex Virus Amplicon Vectors
Authors: Kutubuddin Mahmood , Federoff Howard J. , Challita-Eid Pia M. , Halterman Marc , Day Brian , Atkinson Meredith , Planelles Vicente , Rosenblatt Joseph D. 
Published: October 2019

AbstractHerpes simplex virus amplicon vectors expressing RANTES (HSVrantes) and the T-cell costimulatory ligand B7.1 (HSVB7.1) were studied for their ability to elicit a tumor-specific T-cell response in a murine lymphoma model. HSVB7.1- and HSVrantes-transduced EL4 cells expressed high levels of B7.1 and RANTES as analyzed by flow cytometry and enzyme-linked immunosorbent assay, respectively. Inoculation of ex vivo HSVB7.1 transduced cells in syngeneic mice resulted in regression of both transduced cells and nontransduced cells inoculated contralaterally. Direct intratumoral injection of HSVB7.1 and/or HSVrantes alone or in combination into established EL4 tumors led to complete tumor regression in injected tumors as well as in nontransduced contralaterally implanted tumor, whereas control tumors or tumors injected with HSVlac expressing β-galactosidase did not regress. Maximal protection was achieved with combined injection of HSVB7.1 and HSVrantes; mice showing tumor regression were resistant to rechallenge with parental EL4 cells, and tumor cell-specific cytolytic T-cell activity was observed in mice demonstrating regression. HSV amplicon-mediated delivery of immune effector molecules may represent a useful strategy for immunotherapy in the setting of pre-existing tumor.
The Biologic Role of Interleukin-8: Functional Analysis and Expression of CXCR1 and CXCR2 on Human Eosinophils
Authors: Petering Holger , Götze Otto , Kimmig Daniela , Smolarski Regina , Kapp Alexander , Elsner Jörn 
Published: October 2019

AbstractChemokines play an important role in attracting granulocytes into sites of inflammation. Two chemokine subfamilies differ in their biologic activity for different granulocyte subsets. Whereas CXC chemokines such as interleukin-8 (IL-8) activate predominantly neutrophils, CC chemokines such as RANTES and eotaxin activate predominantly eosinophils. However, controversial results have been published in the past regarding the biologic role of IL-8 in eosinophil activation, particularly in allergic diseases. In this study, we investigated the functional evidence and expression of both IL-8 receptors, CXCR1 and CXCR2, on highly purified human eosinophils. In the first set of experiments, a chemotaxis assay was performed showing that IL-8 did not induce chemotaxis of eosinophils. In addition, and in contrast to neutrophils and lymphocytes, IL-8 did not induce a rapid and transient release of cytosolic free Ca2+([Ca2+]i) in eosinophils, even after preincubation with TH1- and TH2-like cytokines. To investigate whether neutrophil contamination might be responsible for the reported IL-8 effects on eosinophils, neutrophils were added to highly purified eosinophils from the same donor in different concentrations. Interestingly, as little as 5% of neutrophil contamination was sufficient to induce an increase of [Ca2+]iafter stimulation with IL-8. Flow cytometry experiments with monoclonal antibodies against both IL-8 receptors demonstrated no expression of CXCR1 and CXCR2 on eosinophils before or after cytokine activation. Reverse transcriptase-polymerase chain reaction experiments showed that eosinophils, in contrast to neutrophils and lymphocytes, did not express mRNA for CXCR1 and CXCR2. In summary, this study clearly demonstrates that CXCR1 and CXCR2 are not expressed on human eosinophils, even after priming with different bioactive cytokines. Because the CXC chemokine IL-8 did not induce in vitro effects on human eosinophils, IL-8 may also not contribute in vivo to the influx of eosinophil granulocytes into sites of allergic inflammation. Our results suggest that CC chemokines such as eotaxin, eotaxin-2, and MCP-4 are predominant for the activation of eosinophils.
Extreme Leukoreduction of Major Histocompatibility Complex Class II Positive B Cells Enhances Allogeneic Platelet Immunity
Authors: Semple John W. , Speck Edwin R. , Cosgrave Donna , Lazarus Alan H. , Blanchette Victor S. , Freedman John 
Published: October 2019

AbstractIn a murine model of platelet alloimmunization, we examined the definitive role that mononuclear cells (MC) have in modulating platelet immunity by using platelets from severe combined immunodeficient (SCID) mice. CB.17 (H-2d) SCID or BALB/c (H-2d) mouse platelets were transfused weekly into fully allogeneic CBA (H-2k) mice and antidonor antibodies measured by flow cytometry. MC levels in BALB/c platelets were 1.1 ± 0.6/μL and SCID mouse platelets could be prepared to have significantly lower (&lt;0.05/μL) MC numbers. Transfusions with 108 BALB/c platelets (containing ≈100 MC/transfusion) stimulated IgG antidonor antibodies in 100% of the recipients by the fifth transfusion, whereas 108 SCID mouse platelets (containing ≈5 MC/transfusion) stimulated higher-titered IgG alloantibodies by the second transfusion. When titrations of BALB/c peripheral blood MC were added to the SCID mouse platelets, levels approaching 1 MC/μL reduced SCID platelet immunity to levels similar to BALB/c platelets. Characterization of the alloantibodies showed that the low levels of MC significantly influenced the isotype of the antidonor IgG; the presence of 1 MC/μL was associated with induction of noncomplement fixing IgG1 antidonor antibodies, whereas platelet transfusions, devoid of MC (&lt;0.05/μL), were responsible for complement-fixing IgG2a production. When magnetically sorted defined subpopulations of MC were added to the SCID platelets, major histocompatability complex (MHC) class II positive populations, particularly B cells, were found to be primarily responsible for the reduced SCID mouse platelet immunity. The presence of low numbers of MC within the platelets was also associated with an age-dependent reduction in platelet immunogenicity; this relationship however, was not observed with SCID mouse platelets devoid of MC. The results suggest that a residual number of MHC class II positive B cells within allogeneic platelets are required for maximally reducing alloimmunization.
Marrow Ablative and Immunosuppressive Effects of131I-Anti-CD45 Antibody in Congenic and H2-Mismatched Murine Transplant Models
Authors: Matthews Dana C. , Martin Paul J. , Nourigat Cynthia , Appelbaum Frederick R. , Fisher Darrell R. , Bernstein Irwin D. 
Published: October 2019

AbstractTargeted hematopoietic irradiation delivered by131I-anti-CD45 antibody has been combined with conventional marrow transplant preparative regimens in an effort to decrease relapse. Before increasing the proportion of therapy delivered by radiolabeled antibody, the myeloablative and immunosuppressive effects of such low dose rate irradiation must be quantitated. We have examined the ability of 131I-anti-CD45 antibody to facilitate engraftment in Ly5-congenic and H2-mismatched murine marrow transplant models. Recipient B6-Ly5a mice were treated with 30F11 antibody labeled with 0.1 to 1.5 mCi 131I and/or total body irradiation (TBI), followed by T-cell–depleted marrow from Ly5b-congenic (C57BL/6) or H2-mismatched (BALB/c) donors. Engraftment was achieved readily in the Ly5-congenic setting, with greater than 80% donor granulocytes and T cells after 0.5 mCi 131I (estimated 17 Gy to marrow) or 8 Gy TBI. A higher TBI dose (14 Gy) was required to achieve engraftment of H2-mismatched marrow, and engraftment occurred in only 3 of 11 mice receiving 1.5 mCi131I delivered by anti-CD45 antibody. Engraftment of H2-mismatched marrow was achieved in 22 of 23 animals receiving 0.75 mCi 131I delivered by anti-CD45 antibody combined with 8 Gy TBI. Thus, targeted radiation delivered via131I-anti-CD45 antibody can enable engraftment of congenic marrow and can partially replace TBI when transplanting T-cell–depleted H2-mismatched marrow.