bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of interleukin-3 and granulocyte-macrophage colony-stimulating factor on thrombopoiesis in congenital amegakaryocytic thrombocytopenia
Authors: Guinan EC , Lee YS , Lopez KD , Kohler S , Oette DH , Bruno E , Kozakewich H , Nathan DG , Hoffman R 
Published: October 2019

Abstract
Amegakaryocytic thrombocytopenia (AMT) is a rare and often fatal disorder of infancy and childhood presenting with isolated thrombocytopenia that progresses to marrow failure. The defect in thrombopoiesis is not well understood nor is the etiology of the progressive marrow failure. No standard modality of treatment exists. Here, we evaluated the capacity of marrow cells isolated from five patients with AMT and progressive marrow failure to generate megakaryocyte progenitor cells (CFU-MK). These in vitro studies demonstrated assayable numbers of CFU-MK from all patient bone marrows that responded in vitro to the addition of interleukin-3 (IL-3), granulocyte-macrophage colony-stimulating factor (GM-CSF), or the combination of both. These findings suggest that the defect in AMT might be partially correctable by the administration of these cytokines. A Phase I/II trial of in vivo administration of these same hematopoietins in the identical patients was conducted in which no significant toxicity was observed. IL-3 but not GM-CSF administration resulted in improved platelet counts in two patients and decreased bleeding and transfusion requirement in the remaining three. No clinical benefit was observed when GM-CSF was administered after IL-3 pretreatment. Prolonged IL-3 administration has resulted in platelet increases in an additional two patients. In vitro responsiveness of CFU- MK to either cytokine did not predict the degree of clinical response. Although the optimal dose and schedule of IL-3 either alone or in combination remains to be established, this study suggests that IL-3 may contribute to the treatment of patients with AMT.
Randomized comparison of busulfan and hydroxyurea in chronic myelogenous leukemia: prolongation of survival by hydroxyurea. The German CML Study Group
Authors: Hehlmann R , Heimpel H , Hasford J , Kolb HJ , Pralle H , Hossfeld DK , Queisser W , Loffler H , Heinze B , Georgii A 
Published: October 2019

Abstract
In a randomized multicenter study the influence of hydroxyurea versus busulfan on the duration of the chronic phase and on survival of chronic myelogenous leukemia (CML) was determined. In addition cross resistance and adverse reactions of the drugs were analyzed. From July 1983 to January 1991, 441 CML patients were randomized to receive hydroxyurea or busulfan. Of these, 90.7% were Philadelphia positive; 25.7% were low, 38.2% intermediate, and 36.2% high risk patients according to Sokal's score. The median survival of the busulfan treated Philadelphia-positive patients is 45.4 months and of the hydroxyurea group 58.2 months (P = .008). The survival advantage for the hydroxyurea treated patients is recognized in all risk groups. Sixty four patients reached therapy resistance before blast crisis and were crossed over to the alternative drug. The 23 patients with primary hydroxyurea had a median survival of 5.6 years, the 41 patients with primary busulfan therapy a median survival of 2.7 years (P = .02). Adverse reactions were less frequent with hydroxyurea with no severe adverse effects (lung fibrosis, long lasting bone marrow aplasia). The analysis of white blood cell counts in the course of treatment showed lower counts in the hydroxyurea patients. We conclude that hydroxyurea is superior to busulfan in therapy of CML in chronic phase and should be used as first line therapy. Busulfan may have a role as secondary therapy after hydroxyurea resistance or intolerance.
Constitutive expression of steel factor gene by human stromal cells
Authors: Heinrich MC , Dooley DC , Freed AC , Band L , Hoatlin ME , Keeble WW , Peters ST , Silvey KV , Ey FS , Kabat D 
Published: October 2019

Abstract
Steel factor (SF), the ligand for c-kit, is an essential regulator of normal hematopoiesis, melanogenesis, gametogenesis, and mast-cell growth and development. Hematopoietic stromal cells are important sources of SF, because inactivation of SF in mice results in defects in the support function of hematopoietic stromal cells. To identify specific cells that produce, and factors that govern the expression of the different isoforms of SF in human hematopoiesis, we quantified levels of SF mRNA and membrane-bound protein in human stromal cells before and after exposure to recombinant human interleukin (IL)-1 alpha, a cytokine known to induce the expression of a variety of hematopoietic growth factors. In addition, because stromal cells in longterm bone marrow cultures (LTBMC) are supportive of hematopoietic progenitor cell survival in vitro, while umbilical vein endothelial cells (EC) and diploid fibroblasts (DF) are not, we also sought to test the hypothesis that SF gene expression would differ in cells from LTBMC when compared with EC or DF. Using reverse-transcription polymerase chain reaction amplification (RT-PCR), ribonuclease protection assays (RPA), and Northern blot analysis, SF was found to be constitutively transcribed in EC, DF, and LTBMC. IL-1 alpha neither induced accumulation of SF mRNA nor altered the ratio of exon 6+ to exon 6- transcripts in these stromal cells. By Northern blot analysis, the predominant SF mRNA species was shown to be 5.6 kb; a minor population of 3.6 kb was also found. Low levels of membrane-bound SF protein were found to be constitutively expressed by all three types of stromal cells, and were not regulated by IL-1 alpha. We conclude that the unique capacity of LTBMC to support in vitro hematopoiesis, when compared with EC or DF, cannot be explained on the basis of qualitative or quantitative differences in SF gene expression in these cells.
Efficient killing of chronic B-lymphocytic leukemia cells by superantigen-directed T cells
Authors: Wallgren A , Festin R , Gidlof C , Dohlsten M , Kalland T , Totterman TH 
Published: October 2019

Abstract
In vitro studies have indicated that chronic lymphocytic leukemia of B- cell origin (B-CLL) is resistant to cytotoxic effector lymphocytes such as natural killer and lymphokine activated killer (LAK) cells. We show here that B-cell cells are sensitive to Staphylococcal enterotoxin (SE) A-directed T-cell killing. Activation of the target cells by phorbol ester (tetradecanoyl phorbol acetate, [TPA]) greatly enhances their sensitivity to lysis. In SE-dependent cellular cytotoxicity (SDCC), members of the SE superantigen family form a bridge between T cells and target cells expressing major histocompatability complex class II molecules. Binding of SEA to the T-cell-receptor V beta region induces a strong cytotoxic capacity and cytokine production. Cells from 9 B-CLL patients were cultured in the presence or absence of TPA and used as targets in a 4-hour SDCC assay using an allogeneic T-cell line as effector. At an effector:target cell ratio 30:1, 70% to 80% of TPA- induced B-CLL cells were killed. Even at the effector:target ratio of 3:1, 47% +/- 6% of TPA-activated B-cell cells were lysed compared with 13% +/- 2% of resting cells (P < .001). A T-cell line established from a B-CLL patient killed autologous tumor cells as efficiently as allogeneic effectors. SEA-directed T cells were far more lytic to B-CLL cells compared with LAK cells or lectin (phytohemagglutinin-directed T cells. Mechanisms of SDCC lysis were investigated. Effector plus target cell supernatants contained high levels of tumor necrosis factor (TNF)- alpha and interferon-gamma, but these supernatants were not directly toxic to B-CLL cells in short term culture. High concentrations of recombinant TNF-alpha or TNF-beta had no lytic effect. Addition of neutralizing anti-TNF-alpha and anti-TNF-beta antibodies into the SDCC assay did not inhibit SEA-directed T-cell killing. TPA-activated B-CLL cells showed a 1.2- to 13-fold increased expression of the adhesion molecules intercellular adhesion molecule-1 (ICAM-1), lymphocyte function-associated antigen (LFA)-1, and LFA-3, whereas expression of HLA class II molecules increased up to 5 times. The expression of CD72, CD40, and BB-1/B7 increased 1.8 to 4.5 times. The role of these surface molecules in SDCC was analyzed in blocking experiments with monoclonal antibodies. Antibodies to ICAM-1, CD18, and HLA-DR abolished the cytotoxicity, and a substantial reduction was seen with antibody to CD72.(ABSTRACT TRUNCATED AT 400 WORDS)
Tyrosine phosphorylation of P160 BCR by P210 BCR-ABL
Authors: Lu D , Liu J , Campbell M , Guo JQ , Heisterkamp N , Groffen J , Canaani E , Arlinghaus R 
Published: October 2019

Abstract
It is well established that the chimeric BCR-ABL gene formed by joining parts of the BCR and ABL genes plays a key role in the pathogenesis of Philadelphia (Ph) chromosome-positive leukemias. We report that simultaneous expression of P210 BCR-ABL and P160 BCR in simian COS-1 cells yielded stable complexes of these two proteins, and induced phosphorylation of P160 BCR on tyrosine residues in vivo. Tyrosine phosphorylation of a deletion mutant encoding 553 amino acids of BCR N- terminal sequences was also detected when it was coexpressed with P210 BCR-ABL. We propose that tyrosine phosphorylation of P160 BCR by P210 BCR-ABL and their stable physical interaction may perturb normal BCR functions and that these alterations are directly involved in the pathologic processes found in Ph chromosome-associated leukemias.
A novel 37-Kd adhesive membrane protein from cloned murine bone marrow stromal cells and cloned murine hematopoietic progenitor cells
Authors: Shiota Y , Wilson JG , Harjes K , Zanjani ED , Tavassoli M 
Published: October 2019

Abstract
The adhesion of hematopoietic progenitor cells to bone marrow stromal cells is critical to hematopoiesis and involves multiple effector molecules. Stromal cell molecules that participate in this interaction were sought by analyzing the detergent-soluble membrane proteins of GBI/6 stromal cells that could be adsorbed by intact FDCP-1 progenitor cells. A single-chain protein from GBI/6 cells having an apparent molecular weight of 37 Kd was selectively adsorbed by FDCP-1 cells. This protein, designated p37, could be surface-radiolabeled and thus appeared to be exposed on the cell membrane. An apparently identical 37- Kd protein was expressed by three stromal cell lines, by Swiss 3T3 fibroblastic cells, and by FDCP-1 and FDCP-2 progenitor cells. p37 was selectively adsorbed from membrane lysates by a variety of murine hematopoietic cells, including erythrocytes, but not by human erythrocytes. Binding of p37 to cells was calcium-dependent, and was not affected by inhibitors of the hematopoietic homing receptor or the cell-binding or heparin-binding functions of fibronectin. It is proposed that p37 may be a novel adhesive molecule expressed on the surface of a variety of hematopoietic cells that could participate in both homotypic and heterotypic interactions of stromal and progenitor cells.
Chromosomal assignment of the human thrombin receptor gene: localization to region q13 of chromosome 5
Authors: Bahou WF , Nierman WC , Durkin AS , Potter CL , Demetrick DJ 
Published: October 2019

Abstract
A functional thrombin receptor (TR) structurally related to other members of the seven-transmembrane receptor family has been isolated from diverse cellular types intimately involved in the regulation of the thrombotic response. This receptor recapitulates many of the previously identified sequelae of thrombin-mediated cell activation phenomenon, and requires proteolytic cleavage for downstream effector- response coupling events. Using two complementary approaches, we have now completed the chromosomal assignment of the human thrombin receptor gene. Discordancy analysis of polymerase chain reaction products from a human-rodent hybrid cell mapping panel assigned the sequence to human chromosome 5 with no observed discordancies. Cytogenetic localization using fluorescence in situ hybridization on human metaphase chromosomes specifically localized the human TR gene to region q13 of chromosome 5, confirming its presence as a single-locus gene in the human genome. The chromosomal localization of the human TR gene is at or contiguous with the proximal breakpoint site identified in the majority of patients with the 5q- syndrome (dysmegakaryocytopoiesis and refractory anemia).
Detection of minimal residual disease in acute promyelocytic leukemia by a reverse transcription polymerase chain reaction assay for the PML/RAR-alpha fusion mRNA
Authors: Miller WH Jr , Levine K , DeBlasio A , Frankel SR , Dmitrovsky E , Warrell RP Jr 
Published: October 2019

Abstract
The characteristic reciprocal translocation t(15;17) of acute promyelocytic leukemia (APL) disrupts the PML gene on chromosome 15 and the retinoic acid receptor-alpha (RAR-alpha) gene on chromosome 17. PML/RAR-alpha fusion mRNAs are then transcribed and can be detected by a newly described reverse transcription polymerase chain reaction (RT- PCR) assay. Using RT followed by nested PCR amplification for PML/RAR- alpha, we serially evaluated bone marrow aspirates from patients with APL who were treated with all-trans retinoic acid (RA) for induction, followed by all-trans RA as maintenance or cytotoxic drugs as consolidation. At diagnosis, PML/RAR-alpha mRNA was detected in all patients. After initial therapy with all-trans RA, the RT-PCR assay remained positive after induction of complete remission in 31 of 32 evaluable patients. Maintenance treatment by all-trans RA alone was associated with persistent assay positivity and subsequent clinical relapse in 13 of 13 patients. By contrast, the test became negative in 19 of 20 newly diagnosed patients who received consolidation chemotherapy; the 1 patient who remained positive relapsed at 12 months. Three of the 19 assay-negative patients later converted to positive and subsequently relapsed; the remaining 16 patients have remained RT-PCR negative in sustained first remission, with a median follow-up duration that exceeds 24 months (range, 12+ to 34+ months). Despite induction of complete remission in a high proportion of patients, all-trans RA rarely eradicates molecular evidence of disease in patients with APL; however, subsequent treatment with cytotoxic chemotherapy frequently converts the RT-PCR assay for PML/RAR-alpha to negative. Serial negative tests are associated with prolonged disease- free survival, whereas persistence of a positive test after treatment is highly correlated with subsequent relapse. This test identifies patients in remission at high risk for relapse who may benefit from additional antileukemic therapy.
Neutralizing and nonneutralizing monoclonal antibodies to the human granulocyte-macrophage colony-stimulating factor receptor alpha-chain
Authors: Nicola NA , Wycherley K , Boyd AW , Layton JE , Cary D , Metcalf D 
Published: October 2019

Abstract
A panel of monoclonal antibodies was raised against the low-affinity human granulocyte-macrophage colony-stimulating factor (hGM-CSF) receptor alpha-chain expressed as recombinant protein on murine FDC-P1 cells. All the selected antibodies were of the IgG2A isotype and bound to protein A. They each recognized both native and recombinant receptors by indirect surface immunofluorescence and by immunoprecipitation. Several of the antibodies also recognized presumably denatured receptors as detected by immunoblotting of sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Three different epitopes on the extracellular domain of the GM-CSF receptor alpha-chain were defined by these antibodies, and two of the epitopes did not appear to be involved in binding hGM-CSF or in interactions with the beta-chain of the GM-CSF receptor that are required for high-affinity binding of GM-CSF. On the other hand, the epitope recognized by antibody 2B7–17-A appeared to be critically involved in the binding of GM-CSF because this antibody completely abrogated both high- and low- affinity binding of GM-CSF to native and recombinant receptors. Antibody 2B7–17-A had a relatively high affinity for the GM-CSF receptor alpha-chain (kd = 3 nmol/L) and slow dissociation kinetics (kd = 0.002 min-1). These properties made the 2B7–17-A antibody a potent inhibitor of hGM-CSF biologic action in several different bioassays, with a half-maximal inhibitory dose of about 6 nmol/L (1 microgram/mL). This antibody could prove useful in alleviating any pathologic states mediated by excess GM-CSF levels and in defining the domains of the GM- CSF receptor required for ligand binding.
A recombinant factor VIII A2 domain polypeptide quantitatively neutralizes human inhibitor antibodies that bind to A2
Authors: Scandella D , Mattingly M , Prescott R 
Published: October 2019

Abstract
Human antibodies that inactivate coagulation factor VIII (fVIII), known as inhibitors, have been shown by immunoblotting or immunoprecipitation assays to bind predominantly to epitopes within the A2 and/or C2 domains of the fVIII protein. Because these assays simply measure antibody binding, a soluble recombinant polypeptide containing the fVIII A2 domain was used to develop a quantitative inhibitor neutralization assay for antibodies that bound only to A2 by immunoblotting assay. Antibodies from six of eight inhibitor plasmas were fully neutralized by A2 (> or = 90%), whereas two were only partially neutralized. These results established the fVIII inhibitor properties of anti-A2 antibodies. In immunoprecipitation assays, five of the eight inhibitors also had significant levels of anti-light-chain antibody. In one case, this light-chain antibody was shown to have inhibitor activity. Because it did not bind to the C2 domain, this antibody appears to define a new inhibitor epitope within the fVIII light chain. Another inhibitor, which was partially neutralized by A2, was not neutralized by the light chain, even though it contained anti- light-chain antibodies by immunoprecipitation assay. Our results show additional complexities of the immune response to fVIII.
Lysis of malignant B cells from patients with B-chronic lymphocytic leukemia by autologous T cells activated with CD3 x CD19 bispecific antibodies in combination with bivalent CD28 antibodies
Authors: Bohlen H , Hopff T , Manzke O , Engert A , Kube D , Wickramanayake PD , Diehl V , Tesch H 
Published: October 2019

Abstract
Bispecific antibodies (bi-MABs) can be used to target T cells to autologous tumor cells. It has been shown that the activation of resting human T cells requires two independent signals, namely the cross-linking of the T-cell receptor (TCR)-CD3 complex together with the CD28 homodimer. In the present study, we demonstrate the activation of T cells from patients with chronic lymphocytic leukemia (CLL) using bi-MABs against the CD3 and CD19 antigens (CD3 x CD19) in combination with monospecific, bivalent antibodies against the CD28 antigen. Mononuclear cells from patients with CLL were cultured with the bi-MAB CD3 x CD19 and monospecific CD28 antibodies. The CD3 x CD19 bi-MABs were isolated by the hybridoma-hybridoma fusion technique and purified by hydrophobic interaction chromatography. T-Cell activation as demonstrated by increased proliferation, upregulation of T-cell activation markers (CD25, CD38), and cytotoxicity against autologous CLL cells and allogeneic B cells was shown in seven of eight CLL specimens. The stimulation with CD3 x CD19 bi-MABs with CD28 antibodies preferentially induced proliferation of CD4+ T cells. The effective dose of purified antibodies required for optimal T-cell activation was 100 ng/mL in vitro, which suggests that this antibody combination may be useful for immunotherapy of patients with B-CLL.
Establishment and characterization of a human mixed-lineage, T- lymphoid/myeloid cell line (USP-91)
Authors: Umiel T , Rettenmier CW , Siegel S , Ota S , Shimada H , Tran TW , Pattengale PK 
Published: October 2019

Abstract
We report the establishment of a novel cell line from a pediatric patient with recurrent non-Hodgkin's lymphoma. This cell line, termed USP-91, showed both T-lymphoid cell as well as myeloid (ie, nonlymphoid) cell characteristics using a comprehensive multiparameter approach. The initial growth of this cell line was dependent on the presence of the murine stromal cell line, 14F1.1. Subsequently, a phenotypically stable, stroma-independent cell line was established. Although the recurrent biopsy material and the derivative cell line, USP-91, were clonally-derived from T-lineage lymphoid cells, as evidenced by the same rearrangement of the T-cell receptor-beta locus, USP-91 coexpressed both the T-cell antigens CD7, CD3, and CD4, and the myeloid antigens CD13, CD33, CD11b, and CD34. The myeloid features of USP-91 were most consistent with monocytic differentiation as these cells expressed alpha-napthol acetate esterase, lysozyme, alpha-1- antitrypsin, alpha-1-antichymotrypsin, as well as the cell surface receptor for macrophage colony-stimulating factor. In addition, incubation in the presence of phorbol esters induced USP-91 to exhibit morphologic and functional properties of mature mononuclear phagocytes. The expression of this bilineage phenotype suggests that USP-91 represents the malignant transformation of a progenitor cell capable of either myelomonocytic or T-lymphoid differentiation.
Isolated follicular lymphoma cells are resistant to apoptosis and can be grown in vitro in the CD40/stromal cell system
Authors: Johnson PW , Watt SM , Betts DR , Davies D , Jordan S , Norton AJ , Lister TA 
Published: October 2019

Abstract
Low-grade follicular non-Hodgkin's lymphomas are characterized by the presence of a t(14;18) chromosomal translocation that results in deregulation of the B-cell lymphoma (Bcl-2) gene. Studies in cell lines and transgenic animal models have suggested that this results in the suppression of apoptotic cell death in germinal centers. B lymphocytes from normal germinal centers and lymph nodes infiltrated by follicular lymphoma were isolated by immunomagnetic depletion of cells bearing CD4, CD8, or slgD for study in vitro. Follicular lymphoma cells expressing Bcl-2 protein were shown to resist apoptosis after isolation, and could be induced to proliferate in a culture system previously described for the growth of normal B lymphocytes. By the use of a mouse fibroblast monolayer transfected with the CDw32 Fc receptor to present CD40 monoclonal antibody in the presence of interleukin-4, prolonged culture was possible. Karyotypic analysis of cultured lymphoma cells showed the t(14;18) translocation, with clonal identity confirmed by polymerase chain reaction amplification of the breakpoints and direct sequence analysis. These findings support the hypothesis that resistance to apoptosis is an influence on the initiation of follicular lymphoma, and provide a novel means of studying in vitro the intercellular reactions that may be important in progression of the disease.