bluuebunny/crossref_metadata_2025_split huggingface dataset:
First continuous propagation of B19 parvovirus in a cell line
Authors: Shimomura S , Komatsu N , Frickhofen N , Anderson S , Kajigaya S , Young NS 
Published: October 2019

Abstract
The pathogenic human parvovirus B19 has extreme tropism for human erythroid progenitor cells and has resisted cultivation in conventional cell lines. We report first propagation of this virus in an erythropoietin-dependent strain of a megakaryoblastic leukemia cell line called UT-7. Virus protein was present in about 5% of cells after 1 week of culture. Appropriate ratios of major and minor capsid proteins were determined by immunoblot, and newly synthesized capsid protein was detected by immunoprecipitation of radioactively labeled cell lysates. High molecular weight monomer and dimer intermediates were detected by Southern analysis, indicating active viral replication. Approximately 1,000 genome copies were present per infected cell, and at the optimal multiplicity of infection 20- to 50- fold more virus was produced than inoculated. Virus propagation only occurred in UT-7 cells that were adapted to growth in erythropoietin; virus signal was not detected in UT-7 cells adapted for growth in granulocyte-macrophage colony-stimulating factor or interleukin-3, even with exposure to erythropoietin for several days. Infectious virus was detected in cultures as long as 3 months after inoculation. Despite persistence, there was no evidence of viral integration on Southern analysis. This cell line may prove useful for the production of infectious virus and in the analysis of B19 parvovirus persistence, cytotoxicity, and permissivity.
Frequent incidence of somatic mutations in translocated BCL2 oncogenes of non-Hodgkin's lymphomas
Authors: Tanaka S , Louie DC , Kant JA , Reed JC 
Published: October 2019

Abstract
The majority of non-Hodgkin's B-cell lymphomas contain a t(14;18) translocation that places the bc12 gene into juxtaposition with the transcriptically active Ig heavy-chain locus, thus deregulating the expression of this proto-oncogene. The bc12 gene product is a membrane- associated mitochondrial protein that regulates cell survival through unknown mechanisms. Although overproduction of the normal protein appears sufficient for conferring a selective growth or survival advantage to B cells, point mutations that alter the coding region of translocated bc12 genes have been described previously by others in a lymphoma cell line. However, it is not known whether somatic mutations that alter BCL2 proteins occur in vivo or whether they result from chemotherapy or arise through other mechanisms. For these reasons, we obtained DNA from the t(14;18)-containing tumors of five patients who had not undergone treatment for their disease, and used a polymerase chain reaction (PCR)-mismatch technique for rapid identification of point mutations in a portion of the bc12 open reading frame (ORF) corresponding to the first 131 aminoacids (aa) of the 239 aa p26 BCL2 protein. DNAs from two t(14;18)-containing cell lines were also analyzed. Point mutations in this region of the bc12 gene ORF were detected in three of five patients' tumors and in both cell lines. PCR- mismatch analysis of bc12 in cell lines and non-Hodgkin's lymphoma cases that lacked the t(14;18) translocation was negative, thus establishing the specificity of these results. DNA sequencing determined that these mutations are predicted to produce aa substitutions in the BCL2 proteins of two of the primary tumors and one of the cell lines. Interestingly, two of the patients contained an identical C----T transition that resulted in a nonconservative aa substitution (proline----serine) at position 59 of the BCL2 protein. Further analysis excluded the possibility that these mutations represented hereditary polymorphisms or PCR artifacts. A cluster of four point mutations within the translocation + bc12 allele of one patient had hallmarks of the somatic hypermutation mechanism that is associated with Ig genes and that contributes to antibody diversity. Because of the region of the bcl2 gene analyzed in these t(14;18) translocations is located nearly 300 kbp from the Ig heavy-chain locus, our data suggest that the Ig gene somatic hypermutation mechanism can act over extreme distances of DNA. It remains to be established whether these somatic mutations that alter BCL2 proteins influence the pathobiology of nonHodgkin's lymphomas.
Human lymphokine activated killer (LAK) cells suppress generation of allospecific cytotoxic T cells: implications for use of LAK cells to prevent graft-versus-host disease in allogeneic bone marrow transplantation
Authors: Uberti J , Martilotti F , Chou TH , Kaplan J 
Published: October 2019

Abstract
We have found that murine lymphokine activated killer (LAK) cells have veto and natural suppressor activities in vitro, and prevent graft- versus-host disease (GVHD) in vivo. To determine whether human LAK cells mediate veto and natural suppression we measured their ability to inhibit generation of allospecific cytotoxic T cells (CTL) in mixed lymphocyte culture (MLC). When added to MLCs at low concentrations LAK cells caused veto-type inhibition: stimulator-type LAK cells inhibited generation of CTL but responder or third-party LAK cells did not. At higher concentrations LAK cells caused nonspecific inhibition: all three LAK cell types inhibited generation of CTL. LAK cell veto and natural suppressor activities were largely eliminated by irradiation with 30 Gy and by depletion of CD56+ cells, but increased after depletion of CD3+ cells. LAK cell veto activity is not likely an artifact of cold-target inhibition by the LAK cells themselves or by proliferation of T cells contaminating LAK cell preparations: (1) veto only occurred when LAK cells were added to MLC on days 0 through 2, but not when added on day 5; (2) addition of saturating numbers of labeled targets to fixed numbers of allo-CTL effectors failed to overcome the inhibitory effects of adding stimulator-type LAK cells at the onset of MLC; and (3) CD3-depleted LAK cells showed greater veto activity than threefold greater numbers of control LAK cells. In light of our previous findings in mice, the current results imply that adoptive immunotherapy with LAK cells may be useful in preventing GVHD in human bone marrow transplant recipients.
Glucocorticoids downregulate gene expression of GM-CSF, NAP-1/IL-8, and IL-6, but not of M-CSF in human fibroblasts
Authors: Tobler A , Meier R , Seitz M , Dewald B , Baggiolini M , Fey MF 
Published: October 2019

Abstract
Cytokines such as granulocyte-macrophage colony-stimulating factor (GM- CSF), macrophage-CSF (M-CSF), neutrophil-activating peptide- 1/interleukin-8 (NAP-1/IL-8), and interleukin-6 (IL-6) are pivotal in the regulation of hematopoiesis and immune responses. In mesenchymal cells, their expression is induced by tumor necrosis factor alpha (TNF) and other agents. We now show that, while induction of cytokine expression by TNF in human lung fibroblasts was parallel, glucocorticoid hormones differentially affected their production. Dexamethasone (1 mumol/L) concordantly repressed expression of GM-CSF, NAP-1/IL-8 and IL-6. RNA and protein levels were reduced to approximately 5%, 20%, and 30% of control cells, respectively, as determined by Northern blot analyses and immunoassays. A 50% reduction of RNA levels for all three cytokines occurred in the range of 1 hour. In contrast, dexamethasone (1 mumol/L) did not decrease M-CSF RNA levels and protein release. M-CSF RNA and protein levels were maintained even when dexamethasone (1 mumol/L) was present for the whole duration of a 48-hour TNF stimulation. Further experiments showed that dexamethasone downregulates expression of GM-CSF, NAP-1/IL-8, and IL-6 mainly by decreasing the mRNA stability of these cytokines, and that the dexamethasone-mediated repression of cytokine expression depends on ongoing protein and RNA syntheses. Our study suggests that glucocorticoid hormones repress expression of a set of cytokine genes important in conditions of stress. However, they seem not to affect M- CSF expression, which is likely to be more crucial in maintaining long- term functions of myeloid cells.
Migration of primed human eosinophils across cytokine-activated endothelial cell monolayers
Authors: Moser R , Fehr J , Olgiati L , Bruijnzeel PL 
Published: October 2019

Abstract
Eosinophils are known to adhere to cytokine-activated endothelium. Whereas transendothelial migration for neutrophils is an inevitable consequence of this endothelial-dependent adherence, this has not yet been shown for eosinophils. By means of human umbilical vein endothelial cells (HUVE) grown to confluence on microporous filters as an in vitro model of leukocytic migration across postcapillary venules, we have characterized the conditions leading to endothelium-driven transmigration of blood eosinophils from normals and from patients with allergic asthma. Freshly isolated eosinophils from nonallergic donors adhered to interleukin-1 (IL-1) and tumor necrosis factor-activated HUVE, but did not penetrate these monolayers. In contrast, eosinophils from allergic asthma patients showed an increased adherence and transmigration capacity. This increased functional competence was not caused by a difference in density phenotype, because the eosinophils from both groups showed a comparable density distribution over discontinuous Percoll gradients. Moreover, no difference existed within one group among eosinophils harvested from the Percoll density bands 1.080, 1.085, and 1.090 g/mL in terms of transendothelial migration. In vitro cultivation of freshly isolated eosinophils from nonallergic individuals in the presence of granulocyte-macrophage colony- stimulating factor (GM-CSF) and IL-3 induced a stepwise decrease of the density distribution over such gradients. In contrast, eosinophils from patients with allergic asthma directly shifted to a final density of 1.075 g/mL within 24 hours of culture. Notwithstanding the kinetics of density changes, eosinophils from nonallergic donors already expressed the capacity to transmigrate IL-1-activated HUVE monolayers 20 hours after cultivation with different combinations of GM-CSF, IL-3, and IL- 5. Inhibition studies with monoclonal antibodies showed that endothelium-driven transmigration of eosinophils predominantly implicates CD11/CD18 structures on the eosinophil surface, whereas no significant inhibition was found with the anti-VLA-4 monoclonal antibody HP2/1. From cytofluorometric studies, we conclude that spontaneous transmigration of eosinophils from allergic asthma patients is not accompanied by quantitative upregulation of these antigens. Taken together, these results allow the conclusion that blood eosinophils from allergic asthma patients have undergone in vivo priming, mimicked in vitro by cytokines such as GM-CSF, IL-3, and IL-5, leading to induction of the capacity to migrate across cytokine- activated HUVE monolayers.
Intensive combined therapy for previously untreated aggressive myeloma
Authors: Attal M , Huguet F , Schlaifer D , Payen C , Laroche M , Fournie B , Mazieres B , Pris J , Laurent G 
Published: October 2019

Abstract
A trial was initiated to determine the feasibility and efficacy of a three-phase treatment including: (1) induction chemotherapy (IC); (2) high-dose melphalan with total body irradiation supported by unpurged autologous bone marrow transplantation (ABMT); and (3) interferon (IFN) alpha maintenance treatment, in previously untreated aggressive myeloma. Thirty-five consecutive patients, ages under 65 years, were enrolled. Initial induction therapy was randomized between the VAD regimen (vincristine, doxorubicin, dexamethasone) or the VMCP regimen (vincristine, melphalan, cyclophosphamide, prednisone) that were found to give similar results as IC. Thirty-one of 35 (89%) patients, with good performance status and normal renal function after IC, received ABMT. IFN alpha was started soon after ABMT and was well tolerated. Fifteen of 35 (43%) patients achieved complete response (CR) and 14 of 35 (40%) achieved partial response (PR). Low pretreatment beta 2 microglobulin was the only predictive factor for accomplishing CR. The duration of response was significantly affected by the magnitude of response. The 33-month, post-ABMT probability of progression-free survival was 85% for patients in CR versus 24% for patients in PR. The 42-month, post-diagnosis probability of survival was 81%. This overall strategy may represent an advance in the management of multiple myeloma. Furthermore, the high rate and long duration of CR that we observed in patients with low beta 2 microglobulin suggest that such patients may preferentially benefit from this strategy.
Mobilization of peripheral blood progenitor cells by sequential administration of interleukin-3 and granulocyte-macrophage colony- stimulating factor following polychemotherapy with etoposide, ifosfamide, and cisplatin [see comments]
Authors: Brugger W , Bross K , Frisch J , Dern P , Weber B , Mertelsmann R , Kanz L 
Published: October 2019

Abstract
We report on the requirements that have to be met to combine a standard- dose chemotherapy regimen with broad antitumor activity with the mobilization of peripheral blood hematopoietic progenitor cells. Thirty- two cancer patients were given a 1-day course of chemotherapy consisting of etoposide (VP16), ifosfamide, and cisplatin (VIP; n = 46 cycles), followed by the combined sequential administration of recombinant human interleukin-3 (rhIL-3) and recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF). Control patients received GM-CSF alone or were treated without cytokines. Maximum numbers of peripheral blood progenitor cells (PBPC) were recruited on day 13 to 17 after chemotherapy, with a median of 418 CD34+ cells/microL blood (range, 106 to 1,841) in IL-3/GM-CSF-treated patients, 426 CD34+/microL (range, 191 to 1,380) in GM-CSF-treated patients, and 46 CD34+/microL (range, 15 to 148) in patients treated without cytokines. In parallel, there was an increase in myeloid (10,490 colony-forming unit-granulocyte-macrophage [CFU-GM]/mL blood; range, 1,000 to 23,400), as well as erythroid (10,660 burst-forming unit-erythroid [BFU-E]/mL blood; range, 3,870 to 24,300) and multipotential (840 CFU-granulocyte, erythrocyte, monocyte, megakaryocyte [GEMM]/mL blood; range, 160 to 2,070) progenitor cells in IL-3 plus GM-CSF-treated patients. In GM-CSF-treated patients, significantly less precursor cells of all lineages were mobilized, particularly multipotential progenitors (400 CFU-GEMM/mL blood; range, 200 to 2,150). Only small numbers of CD34+ cells and clonogenic progenitor cells could be recruited in intensively pretreated patients. Our data document that after standard-dose chemotherapy-induced bone marrow hypoplasia, IL-3 plus GM-CSF can be used to recruit PBPC, which might shorten the hematopoietic recovery after high-dose chemotherapy in chemosensitive lymphomas or solid tumors.
Antithrombin III Budapest: a single amino acid substitution (429Pro to Leu) in a region highly conserved in the serpin family
Authors: Olds RJ , Lane DA , Caso R , Panico M , Morris HR , Sas G , Dawes J , Thein SL 
Published: October 2019

Abstract
Antithrombin III (AT) is a major plasma serine protease inhibitor and a member of the serpin family of proteins. We have characterized the molecular and genetic basis of AT Budapest, an inherited variant of AT that is associated with thrombotic disease in affected family members. A single amino acid substitution, 429Pro to Leu, was identified, occurring in a region of the molecule that is highly conserved in members of the serpin family. Two forms of variant protein were present in approximately equal amounts in the plasma of the propositus, who is homozygous for the mutation. One form, which had apparently normal Mr, bound heparin strongly and retained some residual thrombin inhibitory activity. The other form had only weak heparin affinity and no antiproteinase activity, and had slightly decreased mobility on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) under nonreducing conditions; this normalized in the presence of a reducing agent, suggesting it was caused by a change in conformation. Additional support for a difference in conformation of the two forms of variant was provided by the finding that the fraction that bound heparin- Sepharose was recognized by a monoclonal antibody raised against normal AT, whereas the weak-affinity fraction was not.
Sustained human hematopoiesis in sheep transplanted in utero during early gestation with fractionated adult human bone marrow cells
Authors: Srour EF , Zanjani ED , Brandt JE , Leemhuis T , Briddell RA , Heerema NA , Hoffman R 
Published: October 2019

Abstract
Sheep were transplanted in utero during early gestation with subpopulations of adult human bone marrow (BM) cells enriched for human progenitor and hematopoietic stem cells (HSC). Chimerism was documented in three of seven transplanted fetuses using monoclonal antibodies against human-specific hematopoietic cell lineages and/or cytogenetic analysis of BM and peripheral blood cells of recipients. Only chimeric sheep BM cells expressing CD45 (6.0% of total BM cells) formed human hematopoietic colonies in response to human recombinant cytokines as determined by cytogenetic analysis. Sorted CD45+ BM cells developed human T-cell colonies containing CD3+, CD4+, and CD8+ cells. DNA from chimeric BM cells obtained 3 months after birth displayed a finger printing pattern identical to that of DNA from the human donor of the HSC graft. These studies indicate that first trimester sheep fetuses are tolerant of adult human HSC grafts, thus permitting the creation of xenogeneic chimera expressing human myeloid and lymphoid lineages. The present findings also suggest that HSC grafts from immunologically competent, HLA-mismatched adult donors may be useful for correcting human genetic diseases in utero during early gestation.
Absolute requirement of CD11/CD18 adhesion molecules, FcRII and the phosphatidylinositol-linked FcRIII for monoclonal antibody-mediated neutrophil antihuman tumor cytotoxicity
Authors: Kushner BH , Cheung NK 
Published: October 2019

Abstract
We have previously shown that 3F8, a murine IgG3, monoclonal antibody (MoAb) specific for the ganglioside GD2, mediates tumor cell kill in vitro and in vivo. We now describe receptor requirements of polymorphonuclear leukocytes (PMN) in 3F8-mediated cytotoxicity (ADCC) of human GD2 (+) melanoma and neuroblastoma cell lines. PMN from a child with leukocyte adhesion deficiency (LAD) were devoid of CD11/CD18 adhesion molecules and mounted no detectable ADCC. MoAb to CD11b, CD11c, and CD18 each efficiently blocked ADCC by normal PMN. In contrast, a panel of different MoAbs to CD11a had no significant inhibitory effect on ADCC, a finding consistent with the low-to-absent expression of the CD11a ligand, intercellular adhesion molecule-1, on the target cells. Granulocyte-macrophage colony-stimulating factor (GM- CSF) significantly increased the expression of CD11b, CD11c, and CD18 on normal PMN, decreased the expression of Fc receptors (FcR), and enhanced ADCC by normal but not by LAD PMN. MoAbs to FcRII and FcRIII each efficiently blocked ADCC; anti-FcRI MoAb had no effect. Flow cytometry using anti-FcRII MoAb versus anti-FcRIII MoAb did not show cross competition, suggesting that inhibition of ADCC was not a steric effect resulting from FcRII proximity to FcRIII. PMN deficient in FcRIII (obtained from patients with paroxysmal nocturnal hemoglobinuria) and PMN depleted of FcRIII by treatment with elastase or phosphatidylinositol (PI)-specific phospholipase C produced low ADCC, supporting a role for the PI-liked FcRIII. Thus, optimal ADCC using human PMN, human solid tumor cells, and a clinically active MoAb (conditions that contrast with the heterologous antibodies and nonhuman or nonneoplastic targets used in most models of PMN ADCC) required CD11b, CD11c, FcRII, and the PI-linked FcRIII. Furthermore, in this clinically relevant system, GM-CSF enhancement of antitumor PMN ADCC correlated with increased expression of CD11/CD18 molecules.
Posttranslational processing of defensins in immature human myeloid cells
Authors: Valore EV , Ganz T 
Published: October 2019

Abstract
Human neutrophil promyelocytes synthesize, process, and package several microbicidal proteins, including the highly abundant defensins, into their azurophil granules. As deduced from their cDNA sequences, defensins are initially synthesized as 94 amino acid (aa) precursors that must undergo extensive processing. We performed metabolic labeling studies of defensin synthesis in the human promyelocytic cell line HL- 60 and in chronic myeloid leukemia cells, and showed that preprodefensins are processed to mature 29 to 30 aa defensins over 4 to 24 hours via two major intermediates: a 75 aa prodefensin generated by the cleavage of the signal sequence, and a 56 aa prodefensin that results from a subsequent preaspartate proteolytic cleavage. Almost all of the 75 aa form was found in the cytoplasmic/microsomal fraction, whereas the 56 aa prodefensin and mature defensins predominated in the granule-enriched fraction. The 75 aa prodefensin was also selectively released into the culture supernatant. Treatment of HL-60 cells with monensin, chloroquine, or ammonium chloride, substances that neutralize acidic subcellular compartments, partially blocked conversion of the 75 aa prodefensin into 56 aa prodefensin, but did not increase the extracellular release of the 75 aa form. Further studies will be required to determine the role of this processing pathway in subcellular targeting to azurophil granules and avoidance of autocytotoxicity.
Molecular quantification of residual disease in chronic myelogenous leukemia after bone marrow transplantation
Authors: Thompson JD , Brodsky I , Yunis JJ 
Published: October 2019

Abstract
Residual disease remains a major problem in the treatment of human neoplasia. To effectively monitor minimal leukemic activity after bone marrow transplantation (BMT), we used a competitive polymerase chain reaction (PCR) amplification technique to quantify expression of the characteristic bcr-abl fusion message in patients with chronic myelogenous leukemia (CML). Quantitative results were obtained between the 0.001% and 0.1% level in control experiments. This represents a significant advantage over cytogenetic and Southern blotting techniques routinely used to diagnose CML, which may not be sensitive below the 1% level. To illustrate the potential clinical usefulness of the quantitative PCR strategy, we compared results of bcr-abl messenger RNA expression with those obtained using cytogenetic and Southern blotting techniques, in a study of consecutive BM and peripheral blood (PB) samples from two CML patients at high risk for relapse after BMT. One patient received a syngeneic transplant during the chronic phase of the disease and relapse was apparent at the molecular level 4.5 months after BMT, while the patient was in complete clinical remission. The second patient was treated with an allogeneic BMT during the accelerated phase of the disease. A slow, but progressive decrease in bcr-abl expression was observed during the first 12 months after BMT, and expression was undetectable thereafter. Our results indicate that the competitive PCR technique can be used to monitor disease activity in patients at high risk of relapse, while the patients are in complete clinical remission, which should facilitate the early detection of relapse or the identification of progressive disappearance of leukemic activity. The approach used may serve as a model for the study of residual disease in an increasing number of other hematologic malignancies that express cancer-specific RNAs.