bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rhom-2 expression does not always correlate with abnormalities on chromosome 11 at band p13 in T-cell acute lymphoblastic leukemia
Authors: Fitzgerald TJ , Neale GA , Raimondi SC , Goorha RM 
Published: October 2019

Abstract
A frequent site for nonrandom recombination in T-cell acute lymphoblastic leukemia (T-ALL) is chromosome 11 at p13. The molecular characterization of a (7;11)(q35;p13) translocation showed that the translocation breakpoint was 2 kb 5′ to the T-ALLbcr locus resulting in the juxtaposition of the T-cell receptor (TCR) beta gene to the rhom-2 gene locus. Northern blot analysis did not detect expression of the rhom-2 gene in the leukemic blasts of the (7;11) translocation. However, using a sensitive polymerase chain reaction (PCR)-based assay, the (7;11) translocation showed a trace expression of rhom-2 at a level of 0.01% of TCR-beta message. Because rhom-2 is considered a proto- oncogene, the significance of the trace expression of rhom-2 in the (7;11) translocation was investigated by comparing the level of rhom-2 expression in 7 additional T-ALLs, normal thymocytes, and CEM (pre-T) and HPB (mature-T) cell lines using the PCR assay. The CEM cells, normal thymocytes, and one patient, whose blasts had no cytogenetic abnormality of chromosome 11, did not express rhom-2 indicating that rhom-2 is not normally expressed in T cells. The other six T-ALLs fell into three categories: (1) two T-ALLs overexpressed rhom-2 in the presence of a translocation; (2) two T-ALLs had trace expression in the presence of a translocation; and (3) two T-ALLs had trace expression with no observable abnormalities on chromosome 11 at p13. Therefore, the data indicate that not all translocations at the T-ALLbcr locus result in overexpression of rhom-2. To account for the sharp contrast in rhom-2 expression seen in these T-ALLs, a model is proposed with a negative regulatory element in the T-ALLbcr locus that is disrupted in some of the cases leading to overexpression of rhom-2.
T-cell subsets and suppressor cells in human bone marrow
Authors: Schmidt-Wolf IG , Dejbakhsh-Jones S , Ginzton N , Greenberg P , Strober S 
Published: October 2019

Abstract
To characterize immune suppressive and hematopoietic features of enriched subsets of human marrow cells, we separated these cells on Percoll density gradients. CD4+ and CD8+ T cells (CD3+) were enriched in the high-density marrow cell fractions and reduced in low-density fractions. CD4-CD8- (CD3+) T cells expressing the alpha beta T-cell antigen receptor were at least 10 times less numerous than the CD4+ and CD8+ T cells in all fractions. Purified populations of the CD4-CD8- alpha beta + T cells obtained by flow cytometry suppressed the mixed leukocyte reaction (MLR). Another population of suppressor cells that expressed neither T-cell (CD3) nor natural killer cell (CD16) surface markers was also identified. The latter cells had the phenotypic and functional characteristics of “natural suppressor” cells. Suppressor cell activity was enriched in the low-density fractions along with hematopoietic progenitors (colony-forming unit-granulocyte-macrophage and burst-forming unit-erythroid). The progenitor and suppressor cell activities were depleted in high-density fractions. The latter fractions made vigorous responses in the MLR. The low-density fractions, which accounted for less than 10% of the input marrow cells, suppressed the MLR and did not respond. Further evaluation of the low-density fractions may be of value in allogeneic bone marrow transplantation due to the reduction of CD4+ and CD8+ T cells and the enrichment of hematopoietic progenitors as well as immune suppressor cells that may inhibit graft-versus-host disease.
High levels of human glucocerebrosidase activity in macrophages of long- term reconstituted mice after retroviral infection of hematopoietic stem cells
Authors: Correll PH , Colilla S , Dave HP , Karlsson S 
Published: October 2019

Abstract
Gaucher disease is a leading candidate for somatic gene therapy using bone marrow (BM) cells as target tissue. Towards this end, we have constructed a retroviral vector (LG) in which the human glucocerebrosidase (GC) cDNA is driven by the Moloney murine leukemia virus (MoMLV) long terminal repeat (LTR). Day 12 to 14 colony-forming unit-spleen progenitor cells were infected by the LG virus with a 100% efficiency, and GC messenger RNA (mRNA) and protein were detected in the progeny of these cells. Tissues from long-term reconstituted mice analyzed 8 months posttransplantation with LG-infected BM contained the intact provirus at greater than 1 copy per cell, indicating effective infection of hematopoietic stem cells. Human GC mRNA generated by the viral LTR was detected in macrophages as well as other hematopoietic cells. Enzyme activity was increased fivefold and twofold in macrophages from BM and spleen, respectively, and could be precipitated with an antibody specific for human GC. Immunohistochemical analysis detected the human GC protein in 81% of the macrophages from five recipient mice. These data indicate that, after transduction of hematopoietic stem cells, the LG vector is capable of directing expression of human GC in the majority of macrophages from long-term reconstituted mice and producing enzyme levels comparable with endogenous mouse activity, suggesting that this virus may be useful in the treatment of Gaucher disease.
Large, chronic doses of erythropoietin cause thrombocytopenia in mice [see comments]
Authors: McDonald TP , Clift RE , Cottrell MB 
Published: October 2019

Abstract
Both large, acute doses of erythropoietin (EPO) and short-term hypoxia increase platelet counts in mice, but long-term hypoxia causes thrombocytopenia. Therefore, we tested the hypothesis that EPO injected in large, chronic doses (a total of 80 U of EPO over a 7-day period) might cause thrombocytopenia. EPO caused increased red blood cell (RBC) production, ie, increased hematocrits, RBC counts, mean cell volume (MCV), and reticulocyte counts (from P less than .05 to P less than .0005), and decreased thrombocytopoiesis, ie, decreased platelet counts, percent 35S incorporation into platelets, and total circulating platelet counts (TCPC) (P less than .0005). Femoral marrow megakaryocyte size was unchanged, but megakaryocyte number was significantly (P less than .005) reduced in mice treated with EPO. EPO- injected mice had increased spleen volumes (P less than .0005), but blood volumes (BV) were unchanged. In EPO-treated, splenectomized mice, RBC production was also increased (P less than .05 to P less than .0005) and platelet counts, TCPC, and percent 35S incorporation into platelets were decreased (P less than .05), but BV was not altered. Therefore, the decrease in platelet counts observed in EPO-treated mice was not due to increased BV or to an enlarged spleen. In other experiments, mice were rendered acutely thrombocytopenic to increase thrombocytopoiesis, and platelet and RBC production rates were determined. In mice with elevated thrombocytopoiesis, RBC counts, hematocrits, percent 59Fe RBC incorporation values, and MCV were decreased (P less than .05 to P less than .0005). Because 59Fe RBC incorporation and MCV were not elevated, the decrease in RBC counts and hematocrits does not appear to be due to bleeding. Therefore, we show that large, chronic doses of EPO increase erythropoiesis and decrease thrombocytopoiesis. Conversely, acute thrombocytopenia causes increased thrombocytopoiesis and decreased erythropoiesis. These findings support the hypothesis of competition between precursor cells of the erythrocytic and megakaryocytic cell lines (stem-cell competition) as the cause of thrombocytopenia in EPO-treated mice and the cause of anemia in mice whose platelet production rates were increased.
Human endothelial cells express integrin receptors on the luminal aspect of their membrane
Authors: Conforti G , Dominguez-Jimenez C , Zanetti A , Gimbrone MA Jr , Cremona O , Marchisio PC , Dejana E 
Published: October 2019

Abstract
Endothelial cells (EC) form a dynamic interface between blood and the rest of the body. EC surface properties promoting adhesion of reactive plasma proteins and/or circulating cells might be of pivotal importance for the homeostasis of blood and tissues. EC express multiple integrin receptors that promote their attachment to the subendothelial matrix proteins. Among these receptors, alpha v beta 3 is of particular relevance on EC, since it is abundantly expressed and can bind many different matrix and plasma proteins. It is still unknown whether integrin receptors are selectively located to the basal side of EC membrane or may also be exposed on the cell surface in contact with blood. This issue was addressed using different experimental approaches. First, selective surface radioiodination using lactoperoxidase (LPO)-latex beads and immunoprecipitation analysis were performed. We found that cultured EC, similarly to human skin fibroblasts (HSF), expose alpha v beta 3 on both their apical (free) and basal (substratum-attached) surfaces. This held also for other integrins such as alpha 2 beta 1, alpha 3 beta 1, alpha 5 beta 1, and alpha 6 beta 1. Immunoprecipitation data were verified by morphological techniques. Immunofluorescence and immunogold-staining of EC with alpha v beta 3, as well as with beta 1 subfamily antibodies, showed a diffuse and granular distribution of these integrins on EC surface. alpha v beta 3 and beta 1 integrins were also detected on the apical membrane of EC at higher magnification by scanning electron microscopy (SEM). Finally, data obtained on cultured EC were confirmed in vivo on immunogold-labeled ultrathin cryosections of human vessels by transmission electron microscopy (TEM). Data indicate, that in addition to their role in promoting EC attachment to extracellular matrix proteins, integrin receptors of EC can be exposed to blood-stream and eventually be available for binding of plasma proteins and circulating cells.
Apoptotic cell death of primed CD45RO+ T lymphocytes in Epstein-Barr virus-induced infectious mononucleosis
Authors: Uehara T , Miyawaki T , Ohta K , Tamaru Y , Yokoi T , Nakamura S , Taniguchi N 
Published: October 2019

Abstract
The expansion of activated T cells, characterized by the expression of CD45RO as well as HLA-DR antigens, is a central feature in acute infectious mononucleosis (IM) induced by primary infection of Epstein- Barr virus (EBV). However, the fate of these activated T cells in this disease is not clearly understood. We found that, on simple culture, a large proportion of T cells isolated from acute IM patients died rapidly, but only a few T cells from normal individuals did. Morphologic observations and DNA fragmentation analysis showed that the loss of viability of IM T cells after incubation was mediated by apoptosis. IM T cells undergoing apoptosis resided exclusively in the CD45RO+ populations of both CD4+ and CD8+ T cells, most of which were shown to coexpress apoptosis-related Fas antigen. Some cytokines such as interleukin-2 (IL-2), IL-5, and IL-6 could rescue IM T cells from apoptotic cell death. The results seemed to imply that most of primed (CD45RO+) T cells in acute IM might be subject to apoptotic cell death, possibly when leaving from the local sites actively producing certain soluble factors required for their survival. Our studies suggest the programmed cell death of peripheral mature T cells as a mechanism of antigen-driven selection.
Induction of CD11a/leukocyte function antigen-1 and CD54/intercellular adhesion molecule-1 on hairy cell leukemia cells is accompanied by enhanced susceptibility to T-cell but not lymphokine-activated killer- cell cytotoxicity [see comments]
Authors: Jansen JH , van der Harst D , Wientjens GJ , Kooy-Winkelaar YM , Brand A , Willemze R , Kluin-Nelemans HC 
Published: October 2019

Abstract
Some B-cell neoplasms, including hairy cell leukemia (HCL), lack expression of the adhesion molecule leukocyte function antigen-1 (LFA- 1/CD11a). Additionally, HCL cells express relatively low amounts of intercellular adhesion molecule-1 (ICAM-1/CD54) and may therefore be an inappropriate target for recognition by T cells or lymphokine-activated killer (LAK) cells. We tested whether these molecules were inducible on HCL cells and if induction would lead to enhanced susceptibility to lysis by LAK cells or cytolytic T cells. CD11a expression was induced by incubation with interferon-alpha (IFN-alpha) or interleukin-4. CD54 was induced by culturing the cells irrespectively of the addition of cytokines. Expression of CD11a and CD54 did not enhance susceptibility to either autologous or allogeneous LAK cells. However, induction of these adhesion molecules was accompanied by enhanced susceptibility to lysis by cytotoxic T lymphocyte clones. This lysis could be reversed by the addition of anti-CD11a and anti-CD54 antibodies. Finally, we monitored the expression of CD11a and CD54 on HCL cells from patients during IFN-alpha therapy. In one of four patients monitored, we observed rapid in vivo induction of CD11a and CD54 on the leukemic cells during IFN-alpha therapy. These studies provide a model for studying immunosurveillance in HCL.
Molecular monitoring of the myl/retinoic acid receptor-alpha fusion gene in acute promyelocytic leukemia by polymerase chain reaction
Authors: Biondi A , Rambaldi A , Pandolfi PP , Rossi V , Giudici G , Alcalay M , Lo Coco F , Diverio D , Pogliani EM , Lanzi EM 
Published: October 2019

Abstract
The acute promyelocytic leukemia (APL) t(15;17) translocation generates a myl/retinoic acid receptor-alpha (RAR-alpha) chimeric gene that is transcribed as a fusion myl/RAR-alpha messenger RNA. Using primer sets derived from RAR-alpha and myl cDNAs, we were able to amplify the breakpoint sites of the fusion transcripts of all 35 APL RNA samples by reverse polymerase chain reaction (PCR) and nested primer approach of two rounds of amplification. DNA fragments of different size were obtained according to the chromosome 15 breakpoints (intron 3-bcr 3; exon 6-bcr 2; and intron 6-bcr 1). bcr 1 and bcr 3 represent the regions of the myl locus most frequently involved among APL (48.5 and 34.2 of cases, respectively); bcr 3 constitutes 62.5% of cases among M3V as compared with 25.9% of M3 cases. The feasibility of monitoring the APL clone by PCR analysis in five APL patients who received different treatment (chemotherapy, all-trans-retinoic acid or bone marrow transplantation) was evaluated. In five of nine bone marrow samples of patients in complete remission, t(15;17)-positive cells could be detected by PCR analysis. We conclude that PCR amplification of the myl/RAR-alpha junctions represents the easiest and rapid method for diagnosis and monitoring of the APL clone.
Decreased pyrimidine nucleoside monophosphate kinase activity in sickle erythrocytes
Authors: Zerez CR , Lachant NA , Lent KM , Tanaka KR 
Published: October 2019

Abstract
We have previously shown that physiologic concentrations of hemin cause marked inhibition of several red blood cell (RBC) enzymes. Because endogenous heme content is elevated in sickle RBCs, we have examined the activity of hemin-sensitive enzymes in these RBCs. One of the hemin- sensitive enzymes, pyrimidine nucleoside monophosphate kinase (PNMK), was shown to have decreased activity in sickle RBCs relative to RBCs of equivalent cell age. The other hemin-sensitive enzymes, including adenylate kinase (AK), pyrimidine 5′-nucleotidase (P5N), 6- phosphogluconate dehydrogenase (6PGD), and aldolase, had activities that were appropriate for cell age. We have also examined the affinity of the hemin-sensitive enzymes to hemin. Using two different methods, PNMK was shown to have the highest binding affinity to hemin. The exquisite sensitivity of PNMK to inhibition by hemin, coupled with the enzyme's high affinity to hemin, may account for the decrease in PNMK activity and the lack of significant decrease in the other hemin- sensitive enzymes in sickle RBCs. These results suggest that the increased endogenous heme content in sickle RBCs may be responsible for the decrease in PNMK activity. Whether the increased endogenous heme content of sickle RBCs can cause hemolysis indirectly by inhibiting RBC enzymes remains to be determined.
Correlation of CD2 expression with PML gene breakpoints in patients with acute promyelocytic leukemia [see comments]
Authors: Claxton DF , Reading CL , Nagarajan L , Tsujimoto Y , Andersson BS , Estey E , Cork A , Huh YO , Trujillo J , Deisseroth AB 
Published: October 2019

Abstract
The chromosomal translocation t(15;17)(q22:21) of acute promyelocytic leukemia (APL) fuses PML, a novel gene, with RAR alpha, a retinoic acid receptor gene. PML-RAR hybrid transcripts were studied in 18 cases of APL using RNA-PCR. Two forms were noted: one designated 5′, producing a 439-bp chimeric fragment, and a 3′ form, producing a pair of fragments of 765 bp and 909 bp. 5′ forms were found in 7 of the 18 cases while the other 11 patients expressed the 3′ forms. The chromosome 15 specific probes K3 and K2 were used to study genomic breakpoints in 12 APL patients. Comparison of these results with RNA PCR in 11 patients for whom both were available yielded a rearrangement pattern predictive of whether the hybrid transcript was 5′ or 3′. In this way, an additional three patients in whom DNA but not RNA was available were identified as having 3′ (downstream) breakpoints and, therefore, 3′ hybrid forms. Thus, 21 cases categorized as having 5′ or 3′ PML-RAR transcripts were analyzed for various phenotypic differences. Surface phenotyping of leukemic promyelocytes demonstrated expression of the CD2 antigen in all cases with the 5′ splice variant. Only 1 of 11 cases with the 3′ form showed CD2 expression. This difference is significant at P = .001.
C-reactive protein and beta-2 microglobulin produce a simple and powerful myeloma staging system
Authors: Bataille R , Boccadoro M , Klein B , Durie B , Pileri A 
Published: October 2019

Abstract
Multiple myeloma (MM) staging procedures are still inadequate for detection of the optimal therapeutic procedure for an individual patient. The Durie & Salmon staging system and serum beta 2- microglobulin (beta 2M) are used worldwide because of their easy clinical application. Other prognostic parameters, such as myeloma cell proliferative activity, are of exceeding importance, but are not as simple as standard methods. Recently, interleukin-6 (IL-6) has been shown to be a major growth factor for MM. IL-6 is a pleiotropic cytokine acting on several cell lineages, and, at the hepatocyte level, stimulates the synthesis of acute phase proteins, such as the well known C-Reactive Protein (CRP). Serum CRP concentration actually reflects the IL-6 activity. A survival analysis carried out in 162 MM patients at diagnosis showed that serum CRP level is a highly significant prognostic factor. Moreover, serum CRP was independent of serum beta 2M. This feature allowed stratification of MM patients into 3 groups according to CRP and beta 2M serum levels: (1) low risk group, CRP and beta 2M less than 6 mg/L (50% of patients); (2) intermediate risk group, CRP or beta 2M greater than or equal to 6 mg/L (35% of patients); (3) high risk group, CRP and beta 2M greater than or equal to 6 mg/L (15% of patients). Survival was 54, 27, and 6 months, respectively (P less than .0001). We thus propose a new and powerful myeloma staging system based on simple and reliable laboratory evaluations.
Effect of mast cell growth factor (c-kit ligand) on clonogenic leukemic precursor cells
Authors: Goselink HM , Williams DE , Fibbe WE , Wessels HW , Beverstock GC , Willemze R , Falkenburg JH 
Published: October 2019

Abstract
Mast cell growth factor (MGF), the ligand for the c-kit receptor, has been shown to be a hematopoietic growth factor that preferentially stimulates the proliferation of immature hematopoietic progenitor cells (HPC). We studied the effect of MGF on the in vitro growth of clonogenic leukemic precursor cells in the presence or absence of interleukin-3 (IL-3), granulocyte-macrophage colony-stimulating factor (GM-CSF), and/or erythropoietin (EPO). Leukemic blood and bone marrow cells from patients with various types of acute myeloid leukemia (AML), chronic myeloid leukemia (CML) in chronic phase, as well as bone marrow samples from patients with myelodysplastic syndromes (MDS) were studied. MGF as a single factor did not induce significant colony formation by clonogenic leukemic precursor cells. In the presence of IL- 3 and/or GM-CSF, MGF weakly stimulated the colony formation by clonogenic precursor cells from patients with AML. In contrast, in the presence of IL-3 and/or GM-CSF, MGF strongly induced both size and number of leukemic colonies from patients with CML in chronic phase. Furthermore, in the presence of EPO, MGF strongly stimulated erythroid colony formation by CML precursor cells. Cytogenetic analysis of the colonies showed that all metaphases after 1 week of culture were derived from the leukemic clone. In patients with MDS, MGF strongly stimulated myeloid colony formation in the presence of IL-3 and/or GM- CSF (up to fourfold), and erythroid colony formation in the presence of EPO (up to eightfold). Not only the number, but also the size of the colonies increased. In the presence of MGF, the percentage of normal metaphases increased in three patients tested after 1 week of culture compared with the initial suspension, suggesting that the normal HPC were preferentially stimulated compared with the preleukemic precursor cells. In the absence of exogenous EPO and in the presence of 10% human AB serum, MGF in the presence of IL-3 and/or GM-CSF induced erythroid colony formation from normal bone marrow and patients with MDS or CML, illustrating that MGF greatly diminished the EPO requirement for erythroid differentiation. These results indicate that MGF may be a candidate as a hematopoietic growth factor to stimulate normal hematopoiesis in patients with acute myeloid leukemia, or with myelodysplastic syndromes.
Differentiation and functional activity of human eosinophilic cells from an eosinophil HL-60 subline: response to recombinant hematopoietic growth factors [published erratum appears in Blood 1992 Dec 1;80(11):2952]
Authors: Fabian I , Lass M , Kletter Y , Golde DW 
Published: October 2019

Abstract
We studied the effect of hematopoietic growth factors (granulocyte- macrophage colony-stimulating factor [GM-CSF], granulocyte [G]-CSF, interleukin (IL)-1, IL-3, IL-5, IL-6, and macrophage [M]-CSF) on differentiation and functional activity of human eosinophilic HL-60 cells (Eos-HL-60) and compared them with effects on parental HL-60 promyelocytic leukemia cells. Purified biosynthetic GM-CSF and IL-5 enhanced cell proliferation and induced eosinophilic differentiation in the eosinophilic subline in both liquid and agar cultures. IL-3 and IL- 6 stimulated cell proliferation but had no effect on cell differentiation, whereas IL-1 and G-CSF affected neither differentiation nor proliferation of Eos-HL-60 cells under the conditions tested. GM-CSF-, IL-3-, and IL-5-treated Eos-HL-60 cells showed increased O2- production in response to phorbol esters (PMA), enhanced phagocytosis of Candida albicans, and release of the enzymes arylsulfatase, beta-glucuronidase and eosinophil peroxidase (EPO). The degranulation of eosinophils induced by GM-CSF, IL-5, and IL-3 may have relevance to the potential clinical toxicity of these hematopoietins, which also stimulate eosinophilopoiesis. G-CSF had no effect on enzyme release, oxidative metabolism, or phagocytic capacity of Eos-HL-60 cells. IL-5 did not affect proliferation, differentiation, or enzyme release in promyelocytic HL-60 cells. These results indicate the specificity of IL-5 for the eosinophil lineage, confirm the effects of GM-CSF and IL-3 on eosinophilopoiesis and mature eosinophil function in a model system, and indicate the absence of G-CSF and IL-1 stimulation of eosinophils. The Eos-HL-60 line is a useful model for studying human eosinophil responses to cytokines.