bluuebunny/crossref_metadata_2025_split huggingface dataset:
Isolation in a single step of a highly enriched murine hematopoietic stem cell population with competitive long-term repopulating ability
Authors: Szilvassy SJ , Lansdorp PM , Humphries RK , Eaves AC , Eaves CJ 
Published: October 2019

Abstract
A simple procedure is described for the quantitation and enrichment of murine hematopoietic cells with the capacity for long-term repopulation of lymphoid and myeloid tissues in lethally irradiated mice. To ensure detection of the most primitive marrow cells with this potential, we used a competitive assay in which female recipients were injected with male “test” cells and 1 to 2 x 10(5) “compromised” female marrow cells with normal short-term repopulating ability, but whose long-term repopulating ability had been reduced by serial transplantation. Primitive hematopoietic cells were purified by flow cytometry and sorting based on their forward and orthogonal light-scattering properties, and Thy-1 and H-2K antigen expression. Enrichment profiles for normal marrow, and marrow of mice injected with 5-fluorouracil (5- FU) four days previously, were established for each of these parameters using an in vitro assay for high proliferative potential, pluripotent colony-forming cells. When all four parameters were gated simultaneously, these clonogenic cells were enriched 100-fold. Both day 9 and day 12 CFU-S were copurified; however, the purity (23%) and enrichment (75-fold) of day 12 CFU-S in the sorted population was greater with 5-FU-treated cells. Five hundred of the sorted 5-FU marrow cells consistently repopulated recipient lymphoid and myeloid tissues (greater than 50% male, 1 to 3 months post-transplant) when co-injected with 1 to 2 x 10(5) compromised female marrow cells, and approximately 100 were sufficient to achieve the same result in 50% of recipients under the same conditions. This relatively simple purification and assay strategy should facilitate further analysis of the heterogeneity and regulation of stem cells that maintain hematopoiesis in vivo.
Differences between binding of one-chain and two-chain tissue plasminogen activators to non-cross-linked and cross-linked fibrin clots
Authors: Husain SS , Hasan AA , Budzynski AZ 
Published: October 2019

Abstract
Interaction of tissue plasminogen activator (t-PA) with fibrin plays a key role in regulation of plasminogen activation and clot dissolution. Previous investigations of t-PA-fibrin interaction, using incorporation of t-PA into polymerizing fibrin clots, have suggested that no significant differences exist in the binding of one-chain or two-chain t-PA to non-cross-linked or cross-linked fibrin. In the present study, binding of 125I-labeled and affinity-purified one-chain and two-chain forms of t-PA to preformed non-cross-linked or cross-linked, sonicated suspension of fibrin was investigated. Interaction of one-chain t-PA with cross-linked fibrin involved a single type of binding site with dissociation constant (kd) of 0.58 mumol/L and a stoichiometry (n) of 1.5. Interaction of one-chain t-PA with non-cross-linked fibrin, however, involved two classes of binding sites with dissociation constants of 0.32 and 1.5 mumol/L and corresponding number of binding sites equal to 0.57 and 2.0, respectively. In contrast to the binding of one-chain t-PA to cross-linked fibrin by a limited number of sites, two-chain t-PA appeared to involve a considerably greater number of sites (minimum six) whose dissociation constant was 3.2 mumol/L. Interaction of two-chain t-PA with non-cross-linked fibrin also showed the presence of many binding sites (minimum seven) with approximate dissociation constant of 6.4 mumol/L, as well as a few (n = 0.012) high- affinity sites with a kd of 0.011 mumol/L epsilon-Aminocaproic acid did not completely reverse the binding of either one-chain t-PA or two- chain t-PA to fibrin. The present findings suggest that the fibrin- binding properties of t-PA undergo considerable changes on proteolytic conversion from one-chain to two-chain t-PA, catalyzed under physiologic conditions by plasmin. The cleavage of one-chain t-PA to two-chain t-PA allows to bind to a large number of low-affinity binding sites on fibrin. Cross-linking of fibrin by factor XIIIa results in masking of high-affinity binding sites that are present in non-cross- linked fibrin. We propose that both plasmin and factor XIIIa play an important regulatory role in dissolution of blood clots by modulating t- PA-fibrin interaction.
Dengue virus, a flavivirus, propagates in human bone marrow progenitors and hematopoietic cell lines [see comments]
Authors: Nakao S , Lai CJ , Young NS 
Published: October 2019

Abstract
Dengue and other arbovirus diseases are frequently associated with bone marrow failure. We show that dengue type 4 (DEN4) propagates in colonies derived from immature human bone marrow progenitors. DEN4 was propagated in BFU-E-derived colonies and replication was dependent on erythropoietin. DEN4 was not cytotoxic. In inoculated cultures, diffuse bursts with many clusters contained large amounts of DEN4 RNA. In contrast to dengue infection of macrophages, virus propagation in semisolid culture was sustained and not enhanced by subneutralizing amounts of antibody. DEN4 also was efficiently propagated in human hematopoietic cell lines, especially those with erythroid properties. In K562 cells, DEN4 infection persisted for months; greatly slowed cell growth, again without cytotoxicity; and resulted in cytopathic changes in cell appearance. Flaviviruses can infect human hematopoietic cells and alter their proliferative capacity.
In vivo induction of gamma interferon and tumor necrosis factor by interleukin-2 infusion following intensive chemotherapy or autologous marrow transplantation
Authors: Heslop HE , Gottlieb DJ , Bianchi AC , Meager A , Prentice HG , Mehta AB , Hoffbrand AV , Brenner MK 
Published: October 2019

Abstract
Interleukin-2 (IL-2) therapy may improve immune reconstitution and reduce the risk of leukemic relapse in the setting of minimal residual disease by augmenting cytotoxic effector mechanisms directed at residual malignant cells. In addition, IL-2 in vitro promotes the release of cytokines including gamma-interferon (gamma-IFN) and tumor necrosis factor (TNF), which also possess antileukemic activity and can enhance granulocyte function. To determine if IL-2 infusion induces release of gamma-IFN and TNF in vivo in sufficient quantity to mediate these effects, we have measured serum levels of these cytokines and secretion by lymphocytes obtained from patients receiving this cytokine in a phase 1 trial. Serum gamma-IFN was undetectable pre-IL-2 and increased to 1.5 to 17 U/mL during IL-2 infusion (P less than .05). Culture of patient lymphocytes for 48 hours produced 1.2 U gamma-IFN/2 x 10(6) cells/mL pre-IL-2 rising to 50 U/2 x 10(6) cells/mL when the lymphocytes were obtained during therapy (P less than .05). Lymphocyte subset analysis showed that both CD3+ and CD16+ cells secreted gamma- IFN in response to IL-2. TNF secretion by lymphocytes also rose during IL-2 infusion from a mean of 5 U/mL to 14.4 U/mL (P less than .01) although no rise was seen in serum levels. The material secreted by IL- 2-stimulated lymphocytes is bioactive as addition of supernatants from lymphocytes obtained during IL-2 therapy to cultures of myeloid blasts significantly inhibited clonogenic growth. IL-2-induced secretion of these cytokines mediated this inhibition as it could be partially blocked by either anti-gamma-IFN or anti-TNF antibodies. Preincubation of granulocytes with the same supernatants produced enhanced oxidative metabolism, measured by chemiluminescence in response to N-formyl- methionyl-leucyl-phenylalanine (FMLP). This effect also could be partially abrogated by anti-gamma-IFN and anti-TNF antibodies. Therefore, secondary cytokine secretion may boost granulocyte function and contribute to the antileukemic effects of IL-2 infusion in patients following bone marrow transplantation or chemotherapy.
Peripheral lymph node helper T-cell recovery after syngeneic bone marrow transplantation in mice prepared with either gamma-irradiation or busulfan
Authors: Samlowski WE , Araneo BA , Butler MO , Fung MC , Johnson HM 
Published: October 2019

Abstract
The optimum marrow ablative regimen for preparing recipients of bone marrow transplantation (BMT) has not been established. gamma- Irradiation, but not busulfan, produces a characteristic microvascular injury pattern which results in depressed capacity of normal lymphocytes to localize into the lymph nodes of syngeneic murine BMT recipients. Since peripheral lymph nodes are important sites for initiation and amplification of immune responses, the preparative regimen might delay recovery of regionally compartmentalized immune functions after BMT. We evaluated the effects of busulfan and gamma- irradiation on the phenotypic and functional reconstitution of helper T- cell function within the peripheral lymph nodes of BMT recipients. Both marrow ablative regimens caused a protracted delay in regeneration of peripheral lymph node CD4+ T cells. Specific helper T-cell functions, such as contact hypersensitivity and alloantigen responses, remained significantly depressed in the lymph nodes of irradiated mice for prolonged periods (up to 60 weeks). These responses recovered more rapidly in busulfan-treated BMT recipients. In contrast, the capacity of peripheral lymph node T cells to provide “help” for antigen-specific immunoglobulin production was only transiently depressed by either preparative regimen. Our experiments confirm the hypothesis that the marrow ablative regimen, particularly gamma-irradiation, may contribute to the period of immunodeficiency which follows BMT. The pattern of immune recovery observed suggests that preparative total body irradiation (TBI) may selectively depress the regional recovery of the TH1 [interleukin-2 (IL-2) and gamma-interferon (gamma-IFN) secreting] lymphocyte subset.
Suppressive effect of Sl/Sld mouse embryo-derived fibroblast cell lines on diffusible factor-dependent proliferation of mast cells
Authors: Onoue H , Ebi Y , Nakayama H , Ru XM , Kitamura Y , Fujita J 
Published: October 2019

Abstract
Two modes of mast cell growth are present, one dependent on diffusible growth factors (interleukins [IL] 3 and 4) and another dependent on contact with fibroblasts. The 3T3 fibroblast cell lines derived from WCB6F1-+/+ mouse embryos supported the proliferation of cultured mast cells (CMC), whereas the 3T3 fibroblast cell lines from WCB6F1-Sl/Sld mouse embryos did not. To investigate the relationship between growth factor-dependent and fibroblast-dependent growths of mast cells, we cocultured CMC and 3T3 fibroblasts in the presence of diffusible growth factors. WCB6F1-+/+ mouse embryo-derived 3T3 cells did not affect the growth factor-dependent proliferation of CMC, but WCB6F1-Sl/Sld mouse embryo-derived 3T3 cells significantly suppressed the proliferation. Close cell-to-cell contact was necessary for the suppression. The NWS1 fibroblast cell line was established from the spleen cells of an adult WBB6F1-+/+ mouse. Although the NWS1 cell line had no supporting effect on the proliferation of CMC in the absence of diffusible growth factors, it did not suppress the proliferation of CMC induced by the growth factors. The present result suggests that a product of mutant Sl genes may be involved in the suppressive activity of WCB6F1-Sl/Sld mouse embryo-derived 3T3 cells.
Bryostatin 1 induces differentiation of B-chronic lymphocytic leukemia cells
Authors: Drexler HG , Gignac SM , Jones RA , Scott CS , Pettit GR , Hoffbrand AV 
Published: October 2019

Abstract
Peripheral blood cells from nine patients with B-chronic lymphocytic leukemia (B-CLL) were treated in vitro with bryostatin 1 (a macrocyclic lactone derived from a marine invertebrate). Like the phorbol ester 12- 0-tetradecanoyl-phorbol 13-acetate (TPA), bryostatin 1 activates protein kinase C (PKC), which plays a central role in the phosphatidylinositol signal transduction pathway. The effects of bryostatin 1 alone and in combination with TPA or with the calcium mobilizing ionophore A23187 were assessed by morphological appearance, cell adherence and aggregation, RNA and DNA synthesis, and immunoglobulin (Ig) production. While eight of nine B-CLL cultures remained proliferatively inert, bryostatin 1 could effectively trigger activation and differentiation of B-CLL cells in all cases as inferred by the induction of morphological changes, RNA synthesis, and monotypic Ig production. Addition of calcium ionophore A23187 to bryostatin 1- exposed cells resulted in significantly increased values for RNA synthesis and Ig production and in the acquisition of plasmacytoid morphology. Bryostatin 1 and the dual signal of bryostatin 1 plus A23187 mimicked the stimulatory action of TPA and the combination of TPA plus A23187, respectively. Overall, bryostatin 1 was less active than equivalent concentrations of TPA. This lesser efficacy may, however, reflect a quantitative rather than qualitative difference. Bryostatin 1 partially antagonized TPA-mediated effects on B-CLL cells suggesting different modes of action by the two activators. These studies indicate that bryostatin 1 has effective differentiation- inducing properties on B-CLL cells that can differentiation-inducing properties on B-CLL cells that can be accentuated by a calcium ionophore.
Detection of minimal residual disease in acute lymphoblastic leukemia by in vitro amplification of rearranged T-cell receptor delta chain sequences
Authors: Hansen-Hagge TE , Yokota S , Bartram CR 
Published: October 2019

Abstract
Human T-cell receptor (TCR) delta-chain diversity mainly originates from high junctional variability, since only a limited number of germline elements is available. This extraordinary diversity at the V.J junction, due to the use of two D delta elements and extensive incorporation of N nucleotides, constitutes a specific clonal marker for cell populations exhibiting rearranged TCR delta genes. To this end we amplified in vitro by polymerase chain reaction (PCR) the TCR delta junctional region of five acute lymphoblastic leukemias (ALL), isolated respective DNA fragments, and used them directly as clonospecific probes. The combination of PCR technology and hybridization to clonospecific probes permitted the detection of leukemia DNA at dilution of 1:100,000 in all five cases. Moreover, we were able to investigate one of the ALL patients 11 months after achieving continuous complete remission. Conventional Southern blot analysis failed to detect rearranged TCR genes at this stage. However, residual leukemic cells could readily be detected by PCR technique. We conclude that the strategy proposed here is a very sensitive tool to detect minimal residual disease in a significant proportion of human lymphoid neoplasias.
Multipotent stem cell involvement in megakaryoblastic leukemia: cytologic and cytogenetic evidence in 15 patients
Authors: Cuneo A , Mecucci C , Kerim S , Vandenberghe E , Dal Cin P , Van Orshoven A , Rodhain J , Bosly A , Michaux JL , Martiat P 
Published: October 2019

Abstract
Cytologic and cytogenetic results obtained from patients fulfilling the FAB criteria for the diagnosis of acute nonlymphocytic leukemia (ANLL) of megakaryocytic lineage (ANLL-M7) are reported. Eleven cases were de novo ANLL-M7, of whom three presented with acute myelofibrosis. Four cases were megakaryoblastic transformations of chronic myelogenous leukemia (two cases), refractory anemia with excess of blasts (one case), and polycythemia vera (one case). Four patients showed a minority of granular blasts, with occasional Auer rods in one. Positive myeloperoxidase and/or sudan black-B stainings and CD13 positivity in these cases were consistent with the presence of a myeloid involvement. Morphologic evidence of associated myelodysplastic features was detected in all evaluable patients with de novo ANLL-M7. These cytologic findings indicate that ANLL-M7 may frequently represent a multilineage proliferation. Cytogenetic studies revealed -7/7q- and +8, alone or in combination with additional aberrations, in three cases each. Rearrangements involving bands 3q21 or 3q26 were seen in two patients and +21, as an additional aberration, in one. Other structural rearrangements all observed in a single patient were inv(16)(p13q22) at megakaryoblastic relapse with bone marrow eosinophilia, t(13;20)(q13 or 14;q11), del(20)(q11), and der(7)t(7;17)(p14;q22). Most breakpoints of these aberrations are located at bands frequently rearranged in malignant myeloid stem cell disorders. A review of 31 cases of the literature showed a frequent occurrence of -7/7q- and -5/5q- in ANLL- M7. Many of the chromosome aberrations so far described in ANLL-M7 appear to be shared by a spectrum of myeloid neoplasias and may be related to mechanisms conferring proliferative advantage to undifferentiated stem cells.
Acceleration of hemoglobin C crystallization by hemoglobin S
Authors: Lin MJ , Nagel RL , Hirsch RE 
Published: October 2019

Abstract
We previously reported that circulating hemoglobin (Hb) CC erythrocytes contain oxygenated HbC crystals with little or no HbF and that HbF inhibits in vitro crystallization of HbC. We now report that HbS accelerates in vitro crystallization of HbC. Crystals were formed in 1.8 mol/L potassium phosphate buffer, pH 7.4, at 30 degrees C and were counted in several time intervals with a hematocytometer. The hemoglobin composition of Millipore-isolated crystals and supernatant were also analyzed. Under the conditions selected, 100% HbS formed needle-shaped crystals only after two hours. Pure HbC does not form crystals within 15 minutes, whereas a ratio of 10% HbS:90% HbC forms 1,100 crystals/mm3, 20% HbS:80% HbC forms 370 crystals/mm3, and 30% HbS:70% HbC forms 5 crystals/mm3. Crystals formed in the presence of HbS are tetragonal, as are pure HbC crystals. As compared with 100% HbC, HbA or albumin mixed with HbC showed a decreased number of crystals as a result of dilution. Analysis of the Hb content of isolated crystals by citrate agar gel electrophoresis showed that HbS was rapidly incorporated into the crystal in the same ratio over time. These results demonstrate that HbS accelerates crystallization of HbC with respect to the rates of crystallization of any of these two Hbs separately, through a mechanism that involves cocrystallization. These results may be significant in understanding SC disease.
Inhibition of malarial parasite invasion by monoclonal antibodies against glycophorin A correlates with reduction in red cell membrane deformability
Authors: Pasvol G , Chasis JA , Mohandas N , Anstee DJ , Tanner MJ , Merry AH 
Published: October 2019

Abstract
The effect of well-characterized monoclonal antibodies to red cell surface molecules on the invasion of human red cells by the malarial parasites Plasmodium falciparum and Plasmodium knowlesi was examined. Antibodies to glycophorin A (GP alpha) inhibit invasion for both parasite species, and this is highly correlated with the degree to which they decrease red cell membrane deformability as measured by ektacytometry. This effect on rigidity and invasion was also seen with monovalent Fab fragments. The closer the antibody binding site was to the membrane bilayer, the greater was its effect on inducing membrane rigidity and decreasing parasite invasion. Antibodies to the Wright determinant in particular were the most inhibitory. This differential effect of the various antibodies was not correlated with their binding affinities or the number of sites bound per cell. Antibodies to surface molecules other than GP alpha were without effect. A novel mechanism is described whereby monoclonal antibodies and their Fab fragments directed at determinants on the external surface of red cells might act to inhibit invasion by malarial parasites by altering membrane material properties.
Effector function for RAS oncogene in interleukin-3-dependent myeloid cells involves diminished efficacy of prostaglandin E1-mediated inhibition of proliferation
Authors: Derigs HG , Klingberg D , Tricot GJ , Boswell HS 
Published: October 2019

Abstract
Leukemic cell growth in the marrow microenvironment may be modulated by stromal cell products, including stimulatory growth factors and the inhibitory regulator prostaglandin E. The production of both of these stromal cell products induced by cytokine mediators appears to be closely linked. Cyclic AMP (cAMP) is an intracellular second messenger that inhibits myeloid cell proliferation and is produced in myeloid leukemia cells on stimulation of adenylate cyclase enzyme by prostaglandin E1 (PGE1). Cells expressing the product of an RAS oncogene have been observed to display diminished hormone-stimulated adenylate cyclase of membranes. If this observation were applicable to myeloid cells, a potentially important mode for leukemia cells expressing p21 RAS to escape inhibitory regulation within the hematopoietic microenvironment would be identified. We studied an interleukin-3 (IL-3)-dependent myeloid cell line, NFS/N1.H7, and a derivative line transfected with H-RAS codon 12 (T24) oncogene, H7 Neo Ras.F3, for inhibition of proliferation by PGE1, 1 microM, alone or in combination with pertussis toxin, which inactivates Gi, an inhibitory regulatory guanosine triphosphate (GTP)-binding protein of adenylate cyclase. NFS/N1.H7 cells were inhibited in interleukin-3-dependent proliferation (dose range, IL-3 10 to 100 U/mL) by PGE1 79 +/- 11%, by pertussis toxin 51 +/- 9%, and by the combination 92 +/- 2%, whereas H7 Neo RAS.F3 was inhibited 51 +/- 7%, 6 +/- 2%, or 58 +/- 9% by PGE1, pertussis toxin, and the combination, respectively. These differences in capacity for inhibition by adenylate cyclase agonists between RAS- transfectant cells (lower inhibition) versus parent cells (greater inhibition) were all highly significant (P less than .0005). Intracellular cAMP formed on PGE1 stimulation of pertussis-intoxicated cells was 150% lower in RAS-transfectant cells than in parent cells. The adenylate cyclase activity of membranes from pertussis-intoxicated RAS-transfected cells was 1.5 to two times lower than that of pertussis- intoxicated parent-cell membranes on Mg2+-dependent activation by hormone and/or guanine nucleotide. However, very similar adenylate cyclase activity was observed in oncogenic p21 RAS-containing membranes compared with parental membranes under conditions of direct activation by 4 mM Mn2+ and forskolin, where inhibitory or stimulatory G-protein influences are minimal. These studies showed diminished adenylate cyclase activity in mutant RAS-bearing myeloid-cell membranes compared with parent-cell membranes independent of the pertussis toxin-sensitive G protein, Gi.(ABSTRACT TRUNCATED AT 400 WORDS).