bluuebunny/crossref_metadata_2025_split huggingface dataset:
Persistence of Antibody to Human Parvovirus B19 After Allogeneic Bone Marrow Transplantation: Role of Prior Recipient Immunity
Authors: Ang H.A. , Apperley J.F. , Ward K.N. 
Published: October 2019

AbstractHuman parvovirus B19 (B19) IgG was studied retrospectively in 66 allogeneic bone marrow transplantation (BMT) patients using an enzyme-linked immunosorbent assay. Recipient and donor sera had been stored pre-BMT together with sequential sera thereafter. Approximately half of donors and recipients had anti-B19 IgG pre-BMT and thus the relative contributions of donor and recipient immunity to antibody production after transplantation could be assessed. For each patient, a serum taken 2 to 3 years after BMT was also tested and the results show that persistence of B19 antibody depends on prior recipient (P = .0003) but not on donor immunity (P = .8). The findings were similar in both sibling and (VUD) BMT volunteer unrelated donor patients. Analysis of sequential post-BMT sera from 41 of the patients, for whom appropriately timed samples were available, showed primary B19 infection in 3 seronegative individuals, whereas 5 others who were seropositive before BMT underwent recurrent infection. Sequential results from the remaining 33 patients without recent B19 infection showed no evidence for donor antibody transfer and confirmed that antibody persistence depends on prior recipient immunity. B19 IgG levels decreased variably with time and some patients eventually became seronegative. It is concluded that this long-term persistence of B19 antibody post-BMT is most probably due to the existence of long-lived recipient plasma cells.
Tumor Necrosis Factor-α– and Interleukin-6–Triggered Mast Cell Development From Mouse Spleen Cells
Authors: Hu Zhi-Qing , Kobayashi Kazuo , Zenda Naoko , Shimamura Tadakatsu 
Published: October 2019

AbstractWe previously showed that interleukin-3 (IL-3) alone is not sufficient, although it is essential for murine mucosal-type mast cell development and that prostaglandin E (PGE) and interferon-γ (IFN-γ) are critical for survival or differentiation of mast cell precursors. We also confirmed that IL-4 is a key inhibitor for mast cell precursors despite being a growth factor of mast cells. In the present work, mouse spleen cells were cultured with recombinant (r) IL-1β, rIL-5, rIL-6, rIL-9, granulocyte-macrophage colony-stimulating factor (GM-CSF ), stem cell factor (SCF ), tumor transforming growth factor-β (TGF-β), or tumor necrosis factor-α (TNF-α) in the presence of endogenous IL-3. After 12 days of culture, mast cell development was induced by rIL-6 and rTNF-α. rIL-1β, rIL-5, rGM-CSF, rTGF-β and even the mast cell growth factors, rIL-9 and rSCF, failed to induce mast cell development. However, unlike IL-9 and SCF, IL-6 and TNF-α did not promote the growth of mast cells already developed. Macrophage may be one of the responsive cells of IL-6 and TNF-α in the cultures, because removal of macrophages greatly reduced the mast cell development induced by the cytokines. The actions of TNF-α and IL-6 were inhibited by indomethacin, an inhibitor for prostaglandin synthesis, and by neutralizing anti–IFN-γ and anti–IL-3 antibodies. rIL-4, when added at the start of the culture, also inhibited mast cell development induced by rIL-6 and rTNF-α. Nevertheless, neutralizing anti–IL-6 and anti–TNF-α antibodies did not suppress mast cell development induced by PGE and IFN-γ. TNF-α and IL-6 enhanced IFN-γ production, but suppressed IL-4 production in the cultures. Mast cell numbers induced were inversely and directly proportional to IL-4 and IFN-γ levels, respectively. These results indicate that inflammatory mediators as triggers are important for mast cell development, although they are not the mast cell growth factors.
Differential Susceptibility to HIV-GP120–Sensitized Apoptosis in CD4+ T-Cell Clones With Different T-Helper Phenotypes: Role of CD95/CD95L Interactions
Authors: Accornero Paola , Radrizzani Marina , Delia Domenico , Gerosa Franca , Kurrle Roland , Colombo Mario P. 
Published: October 2019

AbstractThe susceptibility of Th1 and Th2 cell clones to apoptosis following HIV-gp120/CD4 cross-linking and TCR activation was investigated. We show that only Th1 clones are susceptible to HIV-gp120-sensitized apoptosis, although both types of clones express similar levels of CD4 and bind similar amounts of recombinant gp120. Both types of clones, however, undergo apoptosis induced by CD95 cross-linking with agonistic monoclonal antibody (MoAb). Apoptosis induced by gp120 in the Th1 clones is inhibited by either an antiCD95 neutralizing MoAb or an anti-CD95L neutralizing MoAb as well as by a specific interleukin-1β converting enzyme (ICE) inhibitor. When triggered to apoptosis by gp120, Th1 but not Th2 clones express both cell-associated and soluble CD95L. The CD95L produced by Th1 clones induces cell death, inhibitable by anti-CD95 neutralizing MoAb, of CD95 positive Jurkat cells. These data suggest that, like activation-induced apoptosis, HIV-gp120 sensitized apoptosis in Th1 clones occurs via CD95/CD95L interaction and that lack or insufficient production of CD95L is responsible, at least in part, for the resistance of Th2 clones to such apoptosis.
Interleukin-12 (IL-12) Production in Whole Blood Cultures From Human Immunodeficiency Virus-Infected Individuals Studied in Relation to IL-10 and Prostaglandin E2 Production
Authors: Meyaard Linde , Hovenkamp Egbert , Pakker Nadine , van der Pouw Kraan Tineke C.T.M. , Miedema Frank 
Published: October 2019

AbstractThe role of interleukin-12 (IL-12) in Th1 cell differentiation is well established. The heterodimer p70, composed of a p40 and a p35 chain, is the biologically active form. IL-12 production by human monocytes is enhanced by interferon-γ (IFN-γ) and inhibited by IL-10 and prostaglandin E2 (PGE2 ). Peripheral blood mononuclear cells from human immunodeficiency virus (HIV)-infected individuals reportedly have impaired IL-12 p40 and p70 production on stimulation with Staphylococcus aureus Cowan I (SAC) in vitro. Both PGE2 and IL-10 previously were proposed to be instrumental in this defect in IL-12 production. Here, we studied IL-12 p40 and p70 production in relation to IL-10 and PGE2 production in whole blood cultures from HIV-infected individuals. On stimulation with lipopolysaccharide, IL-12 production was normal. However, on stimulation with SAC, IL-12 p40 and p70 production was decreased in HIV-infected individuals and correlated significantly with decreased peripheral blood CD4+ T-cell number and T-cell reactivity to CD3 monoclonal antibody in vitro. However, IL-10 and PGE2 production in cultures from HIV-infected individuals was normal and did not relate to IL-12 production. In conclusion, IL-12 production by cells from HIV-infected individuals is impaired under certain conditions in vitro and this decrease is independent of IL-10 or PGE2 production.
Minimally Differentiated Acute Myeloid Leukemia (AML-M0): Comparison of 25 Cases With Other French-American-British Subtypes
Authors: Venditti Adriano , Del Poeta Giovanni , Buccisano Francesco , Tamburini Anna , Cox M. Christina , Stasi Roberto , Bruno Antonio , Aronica Germano , Maffei Laura , Suppo Giovanna , Simone Maria Domenica , Forte Laura , Cordero Valeria , Postorino Massimiliano , Tufilli Vincenza , Isacchi Giancarlo , Masi Mario , Papa Giuseppe , Amadori Sergio 
Published: October 2019

Abstract
We compared the immunophenotypic and karyotypic features of 25 cases of minimally differentiated acute myeloid leukemia (AML-M0) with those of 247 cases comprising all AML French-American-British (FAB) classification. Myeloperoxidase (MPO) was detectable with a specific monoclonal antibody in all cases of AML-M0, whereas CD13 and CD33 were both negative in 4 of the 25 cases. Thus, anti-MPO reliably detects minimal myeloid differentiation in AML-M0. CD34 and terminal deoxynucleotidyl transferase (TdT) were more frequently expressed in AML-M0 (96% and 68% of the cases, respectively) than in the other FAB subsets (P &lt; . 001 for both). By contrast, GP-170 and CD7 were less frequently expressed in AML-M0 than in FAB classes such as M1, M4, and M5 (P = .02 and .003, respectively). A total of 80% of AML-M0 cases carried lymphoid markers (including TdT), and 48% showed a coordinate positivity for two or more of them. CD2, CD5, CD10, and CD19 were expressed in a similar fashion among the different FAB groups, whereas CD4 expression was significantly more frequent in AML-M0, AML-M4, and AML-M5 (P = .014). AML-M0 was characterized by a more frequent occurrence of complex karyotypes. In addition, approximately 20% of cases had TdT positivity, complex karyotypes, and anomalies of chromosome 5 and/or 7, a pattern not observed in the other FAB subsets. Finally, 80% of anomalies of chromosome 5 and/or 7 in AML-M0 were comprised within complex karyotypes, whereas only 13% of the remaining FAB cases carried this feature. In summary, AML-M0 frequently expresses immunophenotypic and karyotypic aspects that are likely to identify a “stem cell” pattern.
Regulation of Cellular Iron Metabolism by Erythropoietin: Activation of Iron-Regulatory Protein and Upregulation of Transferrin Receptor Expression in Erythroid Cells
Authors: Weiss Günter , Houston Tracey , Kastner Stefan , Jöhrer Karin , Grünewald Kurt , Brock Jeremy H. 
Published: October 2019

AbstractErythropoietin (Epo) is the central regulator of red blood cell production and acts primarily by inducing proliferation and differentiation of erythroid progenitor cells. Because a sufficient supply of iron is a prerequisite for erythroid proliferation and hemoglobin synthesis, we have investigated whether Epo can regulate cellular iron metabolism. We present here a novel biologic function of Epo, namely as a potential modulator of cellular iron homeostasis. We show that, in human (K562) and murine erythroleukemic cells (MEL), Epo enhances the binding affinity of iron-regulatory protein (IRP)-1, the central regulator of cellular iron metabolism, to specific RNA stem-loop structures, known as iron-responsive elements (IREs). Activation of IRP-1 by Epo is associated with a marked increase in transferrin receptor (trf-rec) mRNA levels in K562 and MEL, enhanced cell surface expression of trf-recs, and increased uptake of iron into cells. These findings are in agreement with the well-established mechanism whereby high-affinity binding of IRPs to IREs stabilizes trf-rec mRNA by protecting it from degradation by a specific RNase. The effects of Epo on IRE-binding of IRPs were not observed in human myelomonocytic cells (THP-1), which indicates that this response to Epo is not a general mechanism observed in all cells but is likely to be erythroid-specific. Our results provide evidence for a direct functional connection between Epo biology and iron metabolism by which Epo increases iron uptake into erythroid progenitor cells via posttranscriptional induction of trf-rec expression. Our data suggest that sequential administration of Epo and iron might improve the response to Epo therapy in some anemias.
Characterization of Adult α- and β-Globin Genes in the Zebrafish
Authors: Chan Fung-Yee , Robinson Judith , Brownlie Alison , Shivdasani Ramesh A. , Donovan Adriana , Brugnara Carlos , Kim John , Lau Bing-Chuen , Witkowska H. Ewa , Zon Leonard I. 
Published: October 2019

AbstractDevelopmental switching of hemoglobins (Hbs) occurs in most vertebrates, yet the cellular and molecular basis for this process remains elusive. The zebrafish is a new genetic and developmental system that can be used to study embryogenesis, and mutants with a variety of defects in hematopoiesis have recently been derived. To initiate our studies on Hb switching in this organism, we have characterized the globins expressed in the adult. Reversed-phase high performance liquid chromatography and mass spectrometric analyses of adult peripheral blood hemolysates showed that there are three major α globins and two β globins in circulating erythroid cells. In addition, we have isolated and characterized zebrafish adult α- and β-globin cDNA clones that encode some of these globins. High levels of α- and β-globin gene expression were detected in adult erythroid cells, whereas embryonic erythroid cells expressed little, if any, of these RNAs. We have also shown that the α- and β-globin genes are tightly linked on the same chromosome and are arrayed in a 3′-5′ to 5′-3′ configuration, respectively. The characterization of these genes and regulatory elements in this globin locus will provide insight into the process of globin gene transcription. With these reagents, future studies of Hb switching in zebrafish mutants with defective hematopoiesis will be possible.
Detection of Duffy Antigen in the Plasma Membranes and Caveolae of Vascular Endothelial and Epithelial Cells of Nonerythroid Organs
Authors: Chaudhuri Asok , Nielsen Søren , Elkjaer Marie-Louise , Zbrzezna Valerie , Fang Fang , Pogo A. Oscar 
Published: October 2019

AbstractThe nonerythroid expression of the Duffy blood group protein (gp-Fy) was confined to certain cell types. Immunocytochemistry studies of the kidney showed gp-Fy in the endothelium of glomeruli, peritubular capillaries, vasa recta, and the principal cells (epithelial) of collecting ducts. Gp-Fy was also produced in the endothelial cells of large venules and epithelial cells (type-I) of pulmonary alveoli. In the thyroid, only the endothelial cells of capillaries produced gp-Fy. In the spleen, the endothelial cells of capillaries, high endothelial venule, and sinusoids produced abundant gp-Fy. Ultrastructural studies showed that apical and basolateral plasma membrane domains, including caveolae, had gp-Fy. Immunoblot analysis showed substantially less gp-Fy in nonerythroid cells than in erythrocytes. Moreover, the analyzed nonerythroid organs of Duffy-negative individuals did not produce more gp-Fy to compensate for the lack of this protein in their erythrocytes. The nucleotide sequence and the size of kidney mRNA from a Duffy-positive individual were the same as that of bone marrow. It is assumed, therefore, that nonerythroid Duffy protein is the product of the same gene as that of bone marrow. This notion is reinforced by the fact that nonerythroid and erythroid gp-Fy have the same antigenic domains.
Stat1 Is Induced and Activated by All-Trans Retinoic Acid in Acute Promyelocytic Leukemia Cells
Authors: Gianni Maurizio , Terao Mineko , Fortino Ida , LiCalzi Marco , Viggiano Vincenzo , Barbui Tiziano , Rambaldi Alessandro , Garattini Enrico 
Published: October 2019

Abstract
Treatment of freshly isolated acute promyelocytic leukemia (APL) cells and the myelogenous leukemia cell lines, NB4, HL-60, and U937, with all-trans retinoic acid (ATRA) results in a remarkable elevation in the amounts of Stat1α and Stat2 proteins. Stat1α protein levels are augmented by ATRA as a consequence of elevated amounts of the corresponding transcripts. The retinoid increases the levels of nuclear complexes that are capable of binding to interferon (IFN)-regulated consensus sequences and contain Stat1 and/or Stat2 proteins, and causes a rapid and long-lasting elevation in Stat1α tyrosine phosphorylation. Transient transfection experiments show that ATRA enhances the transactivating properties of Stat1α observed on an appropriate reporter gene, in the presence of the RARα retinoic acid receptor, but not in the presence of the PML-RAR protein. Treatment of NB4 cells with ATRA is associated with a remarkable upregulation of the two IFN-responsive genes IFN-responsive factor 1 and 2′-5′ oligoadenylate synthetase, as well as with an augmentation in the levels of IFNα secretion. Our data show that ATRA is capable of modulating the amounts and the state of activation of some of the components of the IFN intracellular signaling pathways. They also suggest that the retinoid can bypass IFN/IFN-receptor interactions and induce the expression of IFN-regulated genes.
The Primate Erythrocyte Complement Receptor (CR1) as a Privileged Site: Binding of Immunoglobulin G to Erythrocyte CR1 Does Not Target Erythrocytes for Phagocytosis
Authors: Reinagel Michele L. , Gezen Murat , Ferguson Polly J. , Kuhn Susan , Martin Edward N. , Taylor Ronald P. 
Published: October 2019

AbstractThe primate erythrocyte (E) complement receptor, CR1, is a transmembrane glycoprotein located in clusters on the surface of E. In vivo studies have demonstrated that during processing and clearance of complement-opsonized immune complexes, large amounts of immunoglobulin G (IgG) can be bound to primate E via CR1 with no E loss or lysis. However, when comparable amounts of IgG are bound to other sites on E, in many cases the E are cleared from the circulation by the mononuclear phagocytic system. Therefore, due to its role in immune complex processing, CR1 may represent a privileged site on the primate E. To delineate further this property of E CR1, we performed in vitro phagocytosis assays in the absence of complement and examined the ingestion of E, opsonized at various sites with IgG, by peripheral blood monocytes. When either human or rhesus monkey E were opsonized at sites other than CR1, with between 1,000 and 15,000 IgG per E, substantial phagocytosis of E was evident. However, when comparable amounts of IgG were bound exclusively via CR1, little, if any, phagocytosis was observed. The key to the low phagocytic level of E opsonized via CR1 may be related to the requirements of a “zipper mechanism” for phagocytosis first annunciated by Griffin et al. Based on their findings, we suggest that due to the presence of preexisting clusters of CR1 on the E membrane, large amounts of IgG can be bound to E under conditions that preclude circumferential engagement (and phagocytosis) of the entire E by Fc receptors on the monocyte.
Population Size and Radiosensitivity of Murine Hematopoietic Endogenous Long-Term Repopulating Cells
Authors: McCarthy Kenneth F. 
Published: October 2019

Abstract
A new assay is described that measures the numbers (n) of endogenous long-term repopulating cells (eLTRC) surviving sublethal irradiation. The assay is based on analysis of variances of Pgk-1a phenotypes within groups of sublethally irradiated Pgk-1a/b mice. When ln n is plotted as a function of dose, the radiosensitivity (D0) is the negative reciprocal of the slope and the y-intercept is N or total numbers of eLTRC per mouse. The assay is unique in that N is an absolute value not requiring correction for seeding efficiency, or f. From two independent estimates, total numbers of eLTRC were determined to be 8,700 or 11,900 cells per mouse and D0 was found to be 0.82 or 0.83 Gy. If eLTRC are, in fact, the long-term repopulating cells (LTRC) defined by classical transfer assay, then LTRC can home to the marrow with nearly unit efficiency, only one to two LTRC are required for a mouse to survive a radiation LD50/30, and LTRC possess nearly unlimited self-renewal potential.
Maintenance of Human Germinal Center B Cells In Vitro
Authors: Pound John D. , Gordon John 
Published: October 2019

AbstractThe ability to maintain germinal center (GC) B cells in culture should facilitate studies on the molecular and cellular events which accompany affinity maturation and the generation of memory in T-dependent responses. We have investigated the ability of cytokines to maintain human tonsillar GC B cells (IgD−/CD39−/CD38+/CD77+) in the “CD40 culture system.” In the absence of added cytokines, CD40 monoclonal antibody held on CD32-transfected L cells effectively sustained DNA synthesis in GC B cells for a maximum 3 to 4 days. Of the following cytokines (interleukin-1β [IL-1β], IL-2, IL-3, IL-4, IL-6, IL-7, IL-10, and stem cell factor), only IL-2 and IL-4 provided a significant enhancement to DNA synthesis in the CD40 culture system; this was modest and shortterm. Following a study on the cooperative activity between pairs of cytokines, triple combinations were identified that could maintain high levels of GC B-cell stimulation for at least 10 days. IL-10 was a common component of these synergistic cytokine cocktails, which were IL-10 + IL-4 + IL-7; IL-10 + IL-3 + IL-7; IL-10 + IL-1β + IL-2; IL-10 + IL-1β + IL-3, and IL-10 + IL-3 + IL-6. Culture of GC B cells with these cytokine combinations resulted in a net increase in viable cell numbers of 50% to 100% whereas total cell numbers increased up to fourfold. Cells recovered from these cultures retained a GC B-cell phenotype with a significant proportion being CD38+/CD44−, features characteristic of centroblasts. Studies with metabolically inactive CD32-L cells supported a role for stromal cell-derived soluble factors in maintaining GC B cells in vitro.
Expression of Interleukin-7 Receptor by Lineage-Negative Human Bone Marrow Progenitors With Enhanced Lymphoid Proliferative Potential and B-Lineage Differentiation Capacity
Authors: Ryan Daniel H. , Nuccie Bonnie L. , Ritterman Ion , Liesveld Jane L. , Abboud Camille N. , Insel Richard A. 
Published: October 2019

AbstractRelatively little is known about the relationship of lymphoid-associated gene expression to the proliferation and differentiation potential of early human bone marrow lymphoid progenitors. Surface expression of interleukin-7 (IL-7) receptor-α (IL-7Rα), a component of the high-affinity receptor for the lymphoid precursor growth factor IL-7, defined a CD34+ progenitor subset lacking the CD19+ pro-B phenotype but demonstrating markedly enhanced lymphoid clonogenic capacity and the ability to differentiate into pro-B cells in short-term culture. These progenitors expressed mRNA for the lymphoid-associated genes Igβ, RAG-1, and PAX-5, and were uniformly TdT-positive (TdT+). In contrast, IL-7Rα−/CD19−/CD34+ progenitors had a 50-fold reduced lymphoid clonogenic capacity and did not differentiate into pro-B cells in short-term culture. Expression of TdT and the lymphoid-associated genes Igβ and RAG-1, but not PAX-5, was detected in this fraction, although at lower levels than in the IL-7Rα+ progenitors. In contrast to IL-7Rα, loss of the stem cell factor receptor c-kit was associated with enhanced lymphoid clonogenic potential and increased B-lineage differentiation potential. These results indicate that IL-7Rα expression defines entry into a developmental stage characterized by upregulation of multiple lymphoid-associated genes and enhanced fitness for B-lymphoid differentiation. The onset of IL-7Rα and PAX-5 expression immediately before acquisition of CD19 is consistent with evidence suggesting upregulation of CD19 through pathways involving PAX-5 and IL-7.