bluuebunny/crossref_metadata_2025 huggingface dataset:
Development of human megakaryocytes: I. Hematopoietic progenitors (CD34+ bone marrow cells) are enriched with megakaryocytes expressing CD4
Authors: Dolzhanskiy A , Basch RS , Karpatkin S
Published: October 2019

CD34 is expressed by essentially all human hematopoietic progenitors including cells of the megakaryocyte (MK) lineage. We have previously reported CD4 expression by some human MK (Blood 81:2,664, 1993). To study the role of maturation on CD4 expression by MK, we examined CD34+ bone marrow cells for their expression of CD41 (GPIIb-GPIIIa) and CD4 with specific monoclonal antibody (MoAb)-fluorochrome conjugates and for DNA polyploidization with propidium iodide or 7-aminoactinomycin D (7-AAD). Surprisingly, MK were at least 20-fold more common in the CD34+ progenitor pool (approximately 10%) than in the more mature CD34+ population (approximately 0.5%) of low density bone marrow cells. CD4 expression correlated with markers of immaturity in that CD4 was enriched among CD34+ cells, and the proportion of CD4+ MK declined with increasing ploidy. Almost all CD34+ polyploid ( > or = 8N) cells were CD4+. Despite these correlations with immaturity, CD34+CD4+ MK precursors were unable to produce MK colony-forming units (CFU-MK) when cultured under conditions that supported the growth of CFU-MK from CD34+CD4- MK lineage cells. MK became polyploid before the loss of either CD34 or CD4 expression. The presence of CD4 on these cells correlates with the onset of endomitotic reduplication and is associated with the loss of the ability of these cells to undergo normal mitotic division. The role of CD4 on immature MK as a differentiation antigen and/or receptor for the human immunodeficiency virus (HIV)-1 virus remains to be determined.
Biological effects of recombinant human granulocyte colony-stimulating factor in patients with untreated acute myeloid leukemia
Authors: Baer MR , Bernstein SH , Brunetto VL , Heinonen K , Mrozek K , Swann VL , Minderman H , Block AW , Pixley LA , Christiansen NP , Fay JW , Barcos M , Rustum Y , Herzig GP , Bloomfield CD
Published: October 2019

Hematopoietic growth factors are being administered to patients with acute myeloid leukemia (AML) both to shorten the duration of chemotherapy-induced neutropenia and in an attempt to increase cytotoxicity of cell cycle-specific agents. However, limited information is available concerning the effects of growth factors in AML patients. To examine the in vivo effects of recombinant human granulocyte colony-stimulating factor (G-CSF) on AML cells, laboratory studies were performed before and after a 72-hour intravenous infusion of G-CSF (10 micrograms/kg/d) administered to 28 untreated AML patients. Twenty-seven patients (96%) showed increases in at least one of the following parameters after G-CSF: blood blasts, bone marrow (BM) blasts, leukemia cells in S phase or interphase cells with leukemia- specific markers shown by fluorescence in situ hybridization. The median paired change in absolute blast count was +2.7 x 10(9)/L (P = .0001) after G-CSF, as compared with 0.0 during the 72 hours before initiation of G-CSF. The median percentage of BM leukemia cells in S phase increased from 6.0% to 10.7% after G-CSF (median change, %5.9%; P = .009). Interphase BM cells with trisomy 8 or monosomy 7 increased in 6 of 6 patients with these abnormalities (P = .02) with a median percent increase of 47%. Blood neutrophil counts also increased during G-CSF (median paired change, +2.8 x 10(9)/L; P < .0001). Trisomy 8 or monosomy 7 was shown by fluorescence in situ hybridization in post-G- CSF blood neutrophils from 4 of 6 patients but was also present in neutrophils before G-CSF. We conclude that the percentage of leukemia cells in S phase increases and that leukemia cell populations undergo expansion during short-term administration of G-CSF in almost all AML patients.
Primary mediastinal (thymic) B-cell lymphoma is characterized by gains of chromosomal material including 9p and amplification of the REL gene
Authors: Joos S , Otano-Joos MI , Ziegler S , Bruderlein S , du Manoir S , Bentz M , Moller P , Lichter P
Published: October 2019

Primary mediastinal (thymic) B-cell lymphoma is a high-grade non- Hodgkin's lymphoma with unique features. By using comparative genomic hybridization and interphase cytogenetics, 26 tumors were analyzed to identify genomic imbalances. Gains of chromosomal material were much more frequent than losses (110 v 10) and involved chromosomes 9p, 12q, and Xq (31% to 50%). Interestingly, gain of Xq coincided with gain of 9p. Distinct high-level amplifications were found in four subregions. In 2 cases, amplifications of proto-oncogene REL were shown by filter hybridization, indicating a possible pathogenic role of this gene. The characteristic pattern of chromosomal imbalances distinct from other B- cell lymphomas suggests a specific pathway of genetic changes associated with this lymphoma.
Evidence for progenitors of chronic lymphocytic leukemia B cells that undergo intraclonal differentiation and diversification
Authors: Dono M , Hashimoto S , Fais F , Trejo V , Allen SL , Lichtman SM , Schulman P , Vinciguerra VP , Sellars B , Gregersen PK , Ferrarini M , Chiorazzi N
Published: October 2019

Peripheral blood mononuclear cells from five patients with IgG+ B-type chronic lymphocytic leukemia (B-CLL) were analyzed for the presence of clone-specific Ig H chain variable region gene mRNA transcripts linked to C mu and/or C alpha. This was assessed by (1) comparing the lengths of portions of the VHDJH of the IgG+ CLL clones with those of the mu and alpha isotype-expressing B cells, (2) performing clone-specific endonuclease digestion studies, and (3) determining the DNA sequences of the mu and alpha isotype-expressing cDNA. Thus, when B-cell mRNA from these five patients were reverse transcribed with C gamma-specific primers and then amplified by polymerase chain reaction, dominant cDNA were found with lengths corresponding to those of the IgG+ CLL B cell. In addition, in four cases, cDNA of lengths identical to those of the CLL B cell were detected when mRNA was reverse transcribed and amplified using c mu- and/or C alpha-specific primers, strongly suggesting clonal relatedness. These CLL-related mu- and alpha- expressing cDNA were present in greater amounts that unrelated (non- CLL) mu- and alpha-expressing cDNA from normal B cells that used genes of the same VH family. When the sequences of these CLL-related C mu- and C alpha-expressing cDNA were compared with those of the IgG+ CLL clones, it was clear that they were derived from the same ancestral gene as the IgG-expressing CLL B cell, thus documenting their common origin. Finally, nucleotide point mutations were observed in the mu- and alpha-expressing cDNA of certain patients, indicating divergence with the CLL. These data suggest that IgM+ B cells, which are precursors of the leukemic B cells, exist in increased numbers in the blood of most patients with IgG+ B-CELL and that these cells may differentiate, accumulate V genes mutations, and undergo isotype switching in vivo. In addition, the data are consistent with a sequential-hit model for the evolution of CLL.
Mutations in the Wilms' tumor gene WT1 in leukemias
Authors: King-Underwood L , Renshaw J , Pritchard-Jones K
Published: October 2019

The tissue-specific Wilms' tumor gene WT1 is expressed in a range of acute leukemias and hematopoietic cell lines. Using single-strand conformational polymorphism analysis, we have found mutations in the WT1 gene in 4 of 36 acute leukemias. WT1 mutations are found in 15% of cases of acute myeloid leukemia, in which they are associated with a poor response to chemotherapy. The mutations comprise small insertions in exons 1 and 7 and a nonsense mutation in exon 9. All are predicted to produce a truncated WT1 protein with absence or disruption of the zinc finger region. These are the first mutations in the WT1 gene to be described in sporadic leukemia.
A hematopoietic organ-specific 49-kD nuclear antigen: predominance in immature normal and tumor granulocytes and detection in hematopoietic precursor cells
Authors: Lee BC , Shav-Tal Y , Peled A , Gothelf Y , Jiang W , Toledo J , Ploemacher RE , Haran-Ghera N , Zipori D
Published: October 2019

A 49-kD protein was specifically detected in hematopoietic organs by Western blotting with a novel mouse monoclonal antibody (B92) raised against stromal cells. The protein was found in the immunizing cells using a sensitive method. However, its detection in the bone marrow by the B92 antibody seemed to stem from the abundance of p49 in immature cells of the myeloid lineage. Study of the bone marrow following in vivo irradiation or 5-fluorouracil (5-FU) treatment, in vitro culture with differentiation-inducing factors and long-term culture, and cell sorting all pointed in the same direction: the protein was found in early myeloid cells and in hematopoietic precursor cells. These results were in accordance with the specific presence of p49 in primary radiation-induced myeloid leukemia and its absence in spontaneous B lymphoma. Immunofluorescent staining using B92 antibody detected a nuclear antigen forming a dotted pattern in early myeloid cells and day 12 colony-forming units-spleen (CFU-S). Nuclear localization of p49 was further demonstrated by subcellular fractionation followed by Western blotting. We thus identified a nuclear protein that within the hematopoietic population is detected in hematopoietic precursor cells, predominates in early myeloid cells, and is reduced following differentiation. These properties imply that p49 might be involved in the regulation of hematopoietic cell growth or differentiation.
Initiation of the tissue factor pathway of coagulation in the presence of heparin: control by antithrombin III and tissue factor pathway inhibitor
Authors: Jesty J , Lorenz A , Rodriguez J , Wun TC
Published: October 2019

Activation of factor X by both the unactivated tissue factor:factor VII complex (TF:VII) and the activated tissue factor:factor VIIa complex (TF:VIIa) has been studied in the presence of tissue factor pathway inhibitor (TFPI), antithrombin III (ATIII), and heparin. At near-plasma concentrations of TFPI, ATIII, and factor X, factor X activation that occurs in response to TF:VII is essentially abolished in the presence of heparin (0.5 micromol/L). This effect requires both inhibitors, acting on different targets: (1) ATIII, which in the presence of heparin blocks the activation of TF:VII, and (2) TFPI, which inhibits the TF:VIIa that is generated. In the absence of ATIII, TFPI alone with heparin reduces but does not abolish factor X activation. Conversely, in the absence of TFPI, ATIII + heparin reduces but does not abolish TF:VIIa generation and allows continuing activation of factor X. These results indicated that when the unactivated TF:VII complex is the initiating stimulus, heparin-dependent reduction in the rate and extent of factor X activation requires both ATIII and TFPI. In contrast, if TF:VIIa is used to initiate activation, only TFPI is involved in its regulation.
A critical role of VLA-4 in erythropoiesis in vivo
Authors: Hamamura K , Matsuda H , Takeuchi Y , Habu S , Yagita H , Okumura K
Published: October 2019

Hematopoiesis requires specific interactions with the microenvironments, and VLA-4 has been implicated in these interactions based on in vitro studies. To study the role of VLA-4 in hematopoiesis in vivo, we performed in utero treatment of mice with an anti-VLA-4 monoclonal antibody. Although all hematopoietic cells in fetal liver expressed VLA-4, the treatment specifically induced anemia. It had no effect on the development of nonerythroid lineage cells, including lymphoids and myeloids. In the treated liver almost no erythroblast was detected, whereas the erythroid progenitors, which give rise to erythroid colonies in vitro, were present. These results indicate that VLA-4 plays a critical role in erythropoiesis, while it is not critical in lymphopoiesis in vivo.
Role of interleukin-15 in the development of human CD56+ natural killer cells from CD34+ hematopoietic progenitor cells
Authors: Mrozek E , Anderson P , Caligiuri MA
Published: October 2019

Human natural killer (NK) cells are bone marrow (BM)-derived CD2+CD16+CD56+ large granular lymphocytes (LGL) that lack CD3 yet contain the T-cell receptor zeta-chain (zeta-TCR). NK cells provide requisite interferon-gamma (IFN-gamma) during the early stages of infection in several experimental animal models. A number of studies have shown that human CD3-CD56+ NK cells can be obtained from BM- derived CD34+ hematopoietic progenitor cells (HPCs) cultured in the presence of interleukin-2 (IL-2) and an allogeneic feeder cell layer, or IL-2 and other hematopoietic growth factors such as the c-kit ligand (KL). The failure to detect the IL-2 gene product within the BM stroma and the presence of NK cells in IL-2-deficient mice suggested that cytokines other than IL-2 may participate in NK cell differentiation from HPCs in vivo. IL-15 is a cytokine which, while lacking any sequence homology in IL-2, can activate cells via the IL-2 receptor. Here we show that human BM stromal cells express the IL-15 transcript, and supernatants from long-term BM stromal cell cultures contain IL-15 protein. In vitro, CD3-CD56+ NK cells can be obtained from 21-day cultures of CD34+ HPCs supplemented with IL-15 in the absence of IL-2, stromal cells, or other cytokines. The addition of the KL to these cultures had no effect on the differentiation of the CD3-CD56+ cytotoxic effector cells, but greatly enhanced their expansion. The majority of these cells lack CD2 and CD16, but do express zeta-TCR. Similar to NK cells found in peripheral blood, the CD2-CD16-CD56+ NK cells grown in the presence of IL-15 were found to be potent producers of IFN-gamma in response to monocyte-derived cytokines. Thus IL-15, like KL, appears to be produced by BM stromal cells. IL-15 can induce CD34+ HPCs to differentiate into CD3-CD56+ NK cells, and KL can amplify this. Therefore, IL-15 may be a physiologically relevant ligand for NK cell differentiation in vivo.
Fine-structure epitope mapping of antierythropoietin monoclonal antibodies reveals a model of recombinant human erythropoietin structure
Authors: Elliott S , Lorenzini T , Chang D , Barzilay J , Delorme E , Giffin J , Hesterberg L
Published: October 2019

We have isolated and mapped the rHuEPO epitopes for three noncompeting anti-EPO monoclonal antibodies (MoAbs). The MoAb 9G8A recognizes a linear epitope that includes amino acids 13, 16, and 17. MoAb F12 recognizes a conformational epitope that includes amino acids 31 through 33, 86 through 91, and 138. MoAb D11 recognizes a conformational epitope that includes amino acids 64 through 78 and 99 through 110. MoAb D11 neutralizes rHuEPO activity which suggests that its epitope may contain the receptor binding domain. Analysis of the effect of mutations on folding allowed the identification of buried residues, alpha-helical, and non alpha-helical regions. This data along with epitope mapping data of anti rHuEPO monoclonals was used to model rHuEPO protein structure. A model consistent with the data is a 4-helix bundle with short and long interconnecting loops.
Gene transfer of multidrug resistance into a factor-dependent human hematopoietic progenitor cell line: in vivo model for genetically transferred chemoprotection
Authors: Schwarzenberger P , Spence S , Lohrey N , Kmiecik T , Longo DL , Murphy WJ , Ruscetti FW , Keller JR
Published: October 2019

To develop a rapid preclinical in vivo model to study gene transfer into human hematopoietic progenitor cells, MO-7e cells (CD-34+, c-kit+) were infected with multidrug resistance (MDR1)-containing retroviruses and then transplanted into nonobese diabetic severe combined immunodeficient mice (NOD SCID). MO-7e cells infected with a retrovirus encoding the human MDR1 cDNA showed integration, transcription, and expression of the transfered MDR1 gene. This resulted in a 20-fold increase in the resistance of MO-7e cells to paclitaxel in vitro. The expression of the MDR1 gene product was stable over a 6-month period in vitro without selection in colchicine. MO-7e and MDR1-infected MO-7e cells were transplanted into NOD SCID mice to determine whether MDR1 could confer drug resistance in vivo. A sensitive polymerase chain reaction method specific for human sequences was developed to quantitate the level of human cell engraftment in NOD SCID bone marrow (BM) cells. The percentage of human DNA in BM cells from MO-7e- transplanted mice was 10.9% and decreased to 0.7% in mice treated with paclitaxel. The percentage of human DNA in infected-MO-7e transplanted mice was 7.6% and that level was unchanged in mice treated with paclitaxel. These results show that expression of the MDR1 gene in human hematopoietic progenitor cells can confer functional drug resistance in an in vivo model.
CD30 (Ki-1)-positive malignant lymphomas: clinical, immunophenotypic, histologic, and genetic characteristics and differences with Hodgkin's disease
Authors: Filippa DA , Ladanyi M , Wollner N , Straus DJ , O'Brien JP , Portlock C , Gangi M , Sun M
Published: October 2019

This study compares the histologic and immunophenotypic features of 71 cases of primary CD30+ diffuse large-cell lymphomas (DLCL) and 128 cases of Hodgkin's disease (HD) and discusses the clinical features of 52 patients with CD30+ DLCL. It includes analysis of sites of involvement, staging, response to treatment, sites and treatment of recurrences, and disease-free and overall survival. Diagnostic immunophenotypic differences were found between CD30+ DLCL and HD. All cases of CD30+ DLCL were positive for one or more common or lineage- specific lymphocyte antigens or for EMA. In contrast, 96.9% of HD cases were negative for CD45, CD45-RO, CD43, and CD20. The four exceptions are discussed. All cases of HD were negative for EMA. In patients with CD30+ DLCL, a T-cell phenotype was found in 60%, a null-cell type in 22%, and a B-cell type in 18% of the cases. The median age of patients with T- and null-cell phenotype was 22 years (range, 4 to 72). Fifty- two percent of them had high-stage (III and IV) disease and 61% had extranodal involvement at presentation, including 25% with skin lesions. Lymph nodes draining the skin lesions became involved in seven of 11 patients. No patient had initial bone marrow involvement. Most patients were treated with chemotherapy, and 83% had a complete remission. Fifty-four percent remain free of disease with a median follow-up of 47 months. Thirteen patients (29%) had one or more recurrences and five of them remain free of disease after salvage therapy, with a median follow-up period of 79 months. The clinical stage did not affect survival, probably as a result of different therapy. The t(2;5) translocation was found in five of 15 patients who had cytogenetic abnormalities. Of the other 10 cases, the translocation was detected by reverse transcriptase-polymerase chain reaction (RT- PCR) in four of five cases studied. All nine cases were of T- or null- cell phenotype. The cases of B-cell CD30+ DLCL had a characteristic immunophenotype. All were negative for EMA. These patients were older and had frequent bone marrow involvement but no skin infiltration by lymphoma. All three patients who were human immunodeficiency virus- positive (HIV+) had lymphomas of B-cell lineage. Detection of the t(2;5) translocation by molecular genetics is a useful and highly specific marker in the differential diagnosis between HD and CD30+ DLCL.
Cure of disseminated xenografted human Hodgkin's tumors by bispecific monoclonal antibodies and human T cells: the role of human T-cell subsets in a preclinical model
Authors: Renner C , Bauer S , Sahin U , Jung W , van Lier R , Jacobs G , Held G , Pfreundschuh M
Published: October 2019

Cure of a single established human Hodgkin's tumor growing subcutaneously in severe combined immunodeficient (SCID) mice can be achieved with a complex protocol using two bispecific monoclonal antibodies (Bi-MoAb) directed against the Hodgkin's associated CD30 antigen and the T-cell triggering molecules CD3 and CD28, respectively, together with human T cells prestimulated in vitro with Bi-MoAbs in the presence of CD30+ cells. To adapt this model to the clinical situation, disseminated tumors were established in SCID mice by intravenous injection of 2 x 10(7) cells of the Hodgkin's derived cell line L540CY. Treatment of SCID mice bearing disseminated CD30+ Hodgkin's tumors with the combination of CD3/CD30 and CD28/CD30 Bi-MoAbs and naive (ie, not in vitro prestimulated) human T cells resulted in the cure of all appropriately treated animals. T lymphocytes obtained from patients with advanced stage untreated Hodgkin's disease were as effective as lymphocytes from healthy controls. Treatment was effective even when delayed until 2 weeks after tumor inoculation, and application of Bi- MoAbs into SCID mice with circulating human T cells was as effective as injecting the Bi-MoAbs before the lymphocytes. Treatment results with isolated CD4+ and CD8+ human T cells suggest that both subsets are necessary for the Bi-MoAb mediated cure of xenografted human tumors in vivo. The efficacy and practicability of this preclinical immunotherapy protocol support and form the basis for the clinical evaluation of this approach in patients with Hodgkin's disease resistant to standard therapy.
Irradiated B7-1 transduced primary acute myelogenous leukemia (AML) cells can be used as therapeutic vaccines in murine AML
Authors: Dunussi-Joannopoulos K , Weinstein HJ , Nickerson PW , Strom TB , Burakoff SJ , Croop JM , Arceci RJ
Published: October 2019

Recent studies have shown that tumor cells genetically modified by transduction of B7–1, a natural ligand for the T-cell costimulatory molecules CD28 and CTLA-4, are rejected in syngeneic hosts. In these reports, transformed cell lines and drug-selected cells have been used for vaccinations. To determine the effectiveness of B7–1-transduced primary acute myelogenous leukemia (AML) cells on the induction of antitumor immunity, we have studied a murine AML model in which primary AML cells were retrovirally transduced with the murine B7–1 cDNA. A defective retroviral producer clone expressing B7–1 and secreting a high titer of virus was used for infection of AML cells. Unselected transduced AML cells, expressing a high level of B7–1, were used for in vivo vaccinations. Our results show that one intravenous (IV) injection of irradiated B7–1-positive (B7–1+) AML cells can provide long-lasting (5 to 6 months) systemic immunity against subsequent challenge with wild-type AML cells. Furthermore, one exposure to irradiated B7–1+ AML cells results in rejection of leukemia by leukemic mice when the vaccination occurs in the early stages of the disease. The antileukemia immunity is CD8+ T-cell-dependent and B7/CD28-mediated, since in vivo treatment of mice with anti-CD8 monoclonal antibody or CTLA-4 Ig leads to abrogation of the specific antileukemia immune response. These results emphasize that B7–1 vaccines may have therapeutic usefulness for patients with AML.
Characterization of the gene encoding the human LW blood group protein in LW+ and LW- phenotypes
Authors: Hermand P , Le Pennec PY , Rouger P , Cartron JP , Bailly P
Published: October 2019

The LW blood group is carried by a 42-kD glycoprotein that belongs to the family of intercellular adhesion molecules. The LW gene is organized into three exons spanning an HindIII fragment of approximately 2.65 kb. The exon/intron architecture correlates to the structural domains of the protein and resembles that of other Ig superfamily members except that the signal peptide and the first Ig- like domain are encoded by the first exon. The 5′UT region (nucleotides -289 to +9) includes potential binding sites for various transcription factors (Ets, CACC, SP1, GATA-1, AP2) and exhibited a significant transcriptional activity after transfection in the erythroleukemic K562 cells. No obvious abnormality of the LW gene, including the 5′UT region, has been detected by sequencing polymerase chain reaction- amplified genomic DNA from RhD+ or RhD- donors and from an Rhnull variant that lacks the Rh and LW proteins on red blood cells. However, a deletion of 10 bp in exon 1 of the LW gene was identified in the genome of an LW (a- b-) individual (Big) deficient for LW antigens but carrying a normal Rh phenotype. The 10-bp deletion generates a premature stop codon and encodes a truncated protein without transmembrane and cytoplasmic domain. No detectable abnormality of the LW gene or transcript could be detected in another LW(a- b-) individual (Nic), suggesting the heterogeneity of these phenotypes.
Interleukin-13 (IL-13) induces IL-1 receptor antagonist gene expression and protein synthesis in peripheral blood mononuclear cells: inhibition by an IL-4 mutant protein
Authors: Vannier E , de Waal Malefyt R , Salazar-Montes A , de Vries JE , Dinarello CA
Published: October 2019

Interleukin-13 (IL-13) belongs to the IL-4 gene family. Like IL-4, IL- 13 induces IL-1 receptor antagonist (IL-1Ra) synthesis with no effect on IL-1beta synthesis. We investigated whether IL-13 induces IL-1Ra synthesis via a pathway similar to IL-4. In human peripheral blood mononuclear cells, IL-13 (1 to 100 ng/mL alone induced IL-1Ra synthesis in a dose-dependent manner. A single amino acid mutant form of IL-4 (hIL4.Yl24D) induced IL-1Ra synthesis, acting as a partial agonist. However, hIL-4.Yl24D inhibited IL-1Ra synthesis induced by either IL-4 or IL-13. IL-13 alone induced accumulation of IL-1Ra mRNA. Furthermore, IL-13 reduced steady- state levels for IL-1beta mRNA but enhanced those for IL-1Ra mRNA in cells stimulated with lipopolysaccharide (LPS) or IL- 1alpha. Accordingly, IL-13 suppressed IL-1beta synthesis but enhanced IL-1Ra synthesis in these cells. IL-13 reduced the stability of IL- 1beta mRNA (2.9 v 1.7 hours) but failed to modify the stability of IL- 1Ra mRNA (2.7 v 2.5 hours). Moreover, IL-13 induced transcriptional activation of the IL-1Ra gene, but reduced IL-1beta gene transcription. Our results suggest that the commonality between IL-13 and IL-4 in inducing IL-1Ra synthesis results from the engagement of a subunit common to both receptors.
Interleukin-15 promotes the growth of leukemic cells of patients with B- cell chronic lymphoproliferative disorders
Authors: Trentin L , Cerutti A , Zambello R , Sancretta R , Tassinari C , Facco M , Adami F , Rodeghiero F , Agostini C , Semenzato G
Published: October 2019

The recently discovered cytokine, interleukin-15 (IL-15), has been demonstrated to share several biologic properties with IL-2 in different cell systems, including T-cell and natural killer (NK) cell compartments. As for B lymphocytes, IL-15 has been shown to provide stimulatory activities in normal preactivated B cells that are mainly transduced through IL- 2 receptor (IL-2R) complex components. Since leukemic B cells from patients with chronic lymphoproliferative disorders (CLD) bear IL-2R and grow in response to IL-2, we investigated whether IL-15 triggers the proliferation of malignant B cells obtained from 12 patients with B-cell chronic lymphocytic leukemia (B-CLL) and five patients with hairy cell leukemia (HCL). Enriched B cells recovered from five healthy subjects were also studied as controls. IL-15 stimulated the proliferation of freshly isolated leukemic B cells, but not resting normal B lymphocytes, the latter being able to grow in the presence of IL-15 only after in vitro preactivation with phorbol myristate acetate. The proliferation elicited by IL-2 on leukemic cells was comparable to that determined by IL-15. Following addition of graded concentrations of IL-15 to low/intermediate-dose IL-2, resting leukemic B cells showed a higher stimulatory rate than that observed using the two cytokines separately. In normal resting B lymphocytes, this cumulative effect was not observed. The role of different IL-2R subunits in IL-15-driven growth of malignant B cells was investigated both by their expression on leukemic cells and by the block of different IL-2R subunits (p55, p75, and p64) with specific monoclonal antibodies (MoAbs). Using flow cytometry and reverse transcriptase-polymerase chain reaction (RT-PCR) analyses we demonstrated that both B-CLL and HCL leukemic B cells express the beta and gamma chains of the IL-2R system. The stimulatory activity achieved by IL-15 decreased significantly, blocking the beta and gamma chains of the IL-2R. Taken together, these findings demonstrate that IL-15 triggers the growth of leukemic B cells through IL-2R system subunits, pointing to the role of this novel cytokine in regulating the neoplastic proliferation in CLD.
Transactivation of the interleukin-1alpha promoter by human T-cell leukemia virus type I and type II Tax proteins
Authors: Mori N , Prager D
Published: October 2019

Human T-cell leukemia virus type I (HTLV-I)-infected T-cell lines constitutively produce high levels of interleukin-1alpha (IL-1alpha). To analyze the mechanisms that lead to the expression of IL-1alpha in HTLV-I-infected cell lines, we studied regulatory regions of the human IL-1alpha promoter involved in activation of the IL-1alpha gene. IL- 1alpha promoter constructs drive transcription of the chloramphenicol acetyltransferase (CAT) reporter gene in HTLV-I-positive MT-2 cells, which constitutively produce IL-1alpha. In a cotransfection assay, the Tax protein of both HTLV-I and HTLV-II specifically activated transcription from the IL-1alpha promoter in an uninfected Jurkat cell line. A mutant Tax protein deficient in transactivation of genes by the nuclear factor (NF)-kappaB pathway was unable to induce transcriptional activity of IL-1alpha promoter-CAT constructs, but was rescued by exogenous provision of p65/p50 NF-kappaB. We found that two IL-1alpha kappaB-like sites (positions -1,065 to -1,056 and +646 to +655) specifically formed a complex with NF-kappaB-containing nuclear extract from MT-2 cells and that NF-kappaB bound with higher affinity to the 3′ NF-kappaB binding site than to the 5′ NF-kappaB site. Moreover, deletion of either 5′ or 3′ NF-kappaB sites reduced IL-1alpha promoter activity in MT-2 cells and transactivation of the IL-1alpha promoter by exogenous NF-kappaB and Tax in Jurkat cells. These data suggest a general role for Tax induction of IL-1alpha gene transcription by the NF-kappaB pathway. Expression of IL-1alpha by HTLV-I productively infected cells may be important in the hypercalcemia, osteolytic bone lesions, neutrophilia, elevation of C-reactive protein, and fever frequently seen in patients with HTLV-I-induced adult T-cell leukemia/lymphoma.
The diadenosine polyphosphates Ap3A and Ap4A and adenosine triphosphate interact with granulocyte-macrophage colony-stimulating factor to delay neutrophil apoptosis: implications for neutrophil: platelet interactions during inflammation
Authors: Gasmi L , McLennan AG , Edwards SW
Published: October 2019

Incubation of neutrophils with cytokines such as granulocyte macrophage colony-stimulating factor (GM-CSF) delays their loss of function and changes in cellular morphology that are characteristic of apoptosis. Adenosine triphosphate (ATP) and the diadenosine polyphosphates Ap4A and AP3A were almost as effective as GM-CSF in delaying neutrophil apoptosis. The nucleotides could thus preserve cellular morphology, protect against chromatin fragmentation, and preserve functions such as NADPH oxidase activity and expression of CD16. Moreover, addition of ATP, AP3A and AP4A together with GM-CSF resulted in more pronounced protection from apoptosis than was observed during incubation with either the cytokine or the nucleotides alone. Because ATP, Ap3A, and AP4A may be secreted from activated platelets, these observations suggest that platelet-derived products, perhaps acting in combination with endothelial-derived or immune cell-derived cytokines, can regulate neutrophil function during certain types of inflammation.
Reduced invasion and growth of Plasmodium falciparum into elliptocytic red blood cells with a combined deficiency of protein 4.1, glycophorin C, and p55
Authors: Chishti AH , Palek J , Fisher D , Maalouf GJ , Liu SC
Published: October 2019

In this investigation, we have measured the invasion and growth of the malaria parasite Plasmodium falciparum into elliptocytic red blood cells (RBCs) obtained from subjects with homozygous hereditary elliptocytosis. These elliptocytic RBCs have been previously characterized to possess molecular defects in protein 4.1 and glycophorin C. Our results show that the invasion of Plasmodium falciparum into these protein 4.1 (-) RBCs is significantly reduced. Glycophorin C (-) Leach RBCs were similarly resistant to parasite invasion in vitro. The intracellular development of parasites that invaded protein 4.1 (-) RBCs was also dramatically reduced. In contrast, no such reduction of intracellular parasite growth was observed in the glycophorin C (-) Leach RBCs. In conjunction with our recent finding that a third protein termed p55 is also deficient in protein 4.1 (-) and glycophorin C (-) RBCs, the present data underscore the importance of the membrane-associated ternary complex between protein 4.1, glycophorin C, and p55 during the invasion and growth of malaria parasites into human RBCs.
The repopulation potential of fetal liver hematopoietic stem cells in mice exceeds that of their liver adult bone marrow counterparts
Authors: Rebel VI , Miller CL , Eaves CJ , Lansdorp PM
Published: October 2019

Varying, limiting numbers of unseparated or purified cells (Ly-5.1), either from 14.5-day-old fetal liver (FL) or from adult bone marrow (BM) were coinjected with 10(5) unseparated BM cells (Ly-5.2) into lethally irradiated adult C57B1/6 recipients (Ly-5.2). The kinetics of donor cell repopulation of the lymphoid and myeloid compartments by Ly- 5.1+ donor hematopoietic stem cells (ie, competitive repopulation units [CRU]) were monitored at various time points after the transplantation by Ly-5 analysis of the peripheral white blood cells (WBC). Recipients that had received on average less than 2 adult BM or FL CRU did not show a significant difference in the level of donor-reconstitution when analyzed 4 weeks after the transplantation, However, at 8 and 16 weeks, the FL recipients showed a significantly higher percentage of donor- derived nucleated peripheral blood cells than did the recipients of adult BM cells. Analysis of individual mice showed that approximately 80% of the recipients of FL CRU showed an increase in mature WBC output between 4 and 8 weeks after transplantation, whereas this occurred in less than 40% in the recipients of adult BM cells. In addition to this effect on mature cell output, the cellularity of the reconstituted BM was significantly higher in recipients of FL CRU than in recipients of adult BM CRU, even at 7 to 9 months after transplantation, which is consistent with an increased clonal expansion of FL CRU. When marrow cells from primary recipients of FL CRU were injected into secondary recipients, a significantly higher percentage of these mice showed donor-reconstitution of their lymphoid and myeloid compartments (P < .01) and to a greater extent (P < .008) as compared with mice that had received marrow cells from primary recipients of similar numbers of adult BM CRU. Taken together, these results show that individual FL CRU exhibit a greater proliferative activity in vivo than similar cells from adult BM that is accompanied by a greater production of daughter CRU.
The role of MAP kinase kinase in interleukin-3 stimulation of proliferation
Authors: Perkins GR , Marshall CJ , Collins MK
Published: October 2019

Expression of a dominant interfering mutant of MAP kinase kinase (MAPKK) inhibits interleukin-3 (IL-3) activation of MAP kinase in the murine bone marrow-derived cell line BAF3. This results in an increase in the level of IL-3 required to stimulate cell proliferation and suppress apoptosis. When apoptosis is constitutively inhibited by coexpression of bcl-2, the dominant interfering MAPKK inhibits IL-3 driven cell cycle progression. Thus, MAPKK function is necessary for optimal IL-3 inhibition of apoptosis and optimal IL-3 stimulation of entry into S phase. Expression of a constitutively activated mutant of MAPKK does not replace IL-3, but renders cells able to proliferate in a density-dependent manner. Cell contact is required to allow cell proliferation; such contact can be supplied by cells without activated MAPKK.
Adjacent, cooperative elements form a strong, constitutive enhancer in the human granulocyte-macrophage colony-stimulating factor gene [published erratum appears in Blood 1996 Oct 1;88(7):2818]
Authors: Nimer SD , Zhang W , Kwan K , Whang Y , Zhang J , Wang Y [corrected to Whang Y]
Published: October 2019

Both copies of a repeated sequence CATT(A/T), located between bp -53 and -39 in the upstream region of the human GM-CSF gene, are required for mitogen-inducible promoter activity in T lymphocytes. However, the proteins that recognize this region of the granulocyte-macrophage colony-stimulating factor (GM-CSF) promoter, and are responsible for its transcriptional regulatory activity, have not been clearly identified. Using transient transfection assays, we demonstrate that a 19-bp oligonucleotide containing the CATT(A/T) repeats has strong constitutive enhancer activity in both T cell and non-T-cell lines, even though GM-CSF is not normally constitutively expressed by these cells. A 12-bp oligonucleotide, containing only the sequence CATTAATCATTT, lacks enhancer activity indicating that the nucleotides surrounding these sequences are critical for this enhancer activity. The sequence TTTCCT, which can bind members of the ets family of transcription factors, is located just 3′ of these CATT(A/T) repeats, and mutagenesis of the CCT sequence abolishes (1) the constitutive (and mitogen inducible) enhancer activity of the 19-bp GM-CSF sequences, (2) the responsiveness to transactivation by ets-1, and (3) the ability to specifically bind ets-1 and elf-1 in electrophoretic mobility shift assays (EMSA). We demonstrate that although T cells contain nuclear proteins capable of independently recognizing the ets binding site and the CATT(A/T) repeats in EMSAs, both of these regulatory elements are required for enhancer function. The strong constitutive activity of this 19-bp region suggests that negative regulation of the GM-CSF promoter is critical for the restricted expression pattern of GM-CSF mRNA.
Constitutive expression of GATA-1 interferes with the cell-cycle regulation
Authors: Dubart A , Romeo PH , Vainchenker W , Dumenil D
Published: October 2019

GATA-1, mainly expressed during erythroid differentiation, has been shown to regulate the genes specifically expressed in the late stages of erythropoiesis and to protect erythroid cells from apoptosis, suggesting that it might interfere with the cell cycle. By expressing the retrovirally transduced human GATA-1 cDNA in NIH3T3 fibroblasts, we have shown that GATA-1 alone was unable to transactivate its erythroid- specific target genes in these nonerythroid cells. However, GATA-1 expression had a dramatic effect on the proliferation of these fibroblasts. The cloning efficiency of the GATA-1-expressing fibroblasts was maintained but their S phase was greatly elongated and their G1 and G2/M phases were reduced, impairing substantially their proliferation. When cultured at low serum concentrations for 48 hours, GATA-1-expressing fibroblasts failed to accumulate in the G0/G1 phases but did not become serum independent. GATA-1-expressing fibroblasts expressed D1, A, and B1 cyclin mRNAs under conditions of serum starvation or at confluence, whereas these cyclin mRNAs were downregulated in the parental NIH3T3 cells cultured under the same conditions. Moreover, these effects of GATA-1 expression on proliferation were not limited to NIH3T3 cells, since different clones of hGATA-1 virus-infected FDCP-1 cells, a murine interleukin-3- dependent hematopoietic cell line, had a slower growth rate than control cells. Based on these data, we hypothesize that GATA-1 plays a role in the regulation of the cell cycle during terminal erythroid differentiation.
Efficient retroviral transduction of human bone marrow progenitor and long-term culture-initiating cells: partial reconstitution of cells from patients with X-linked chronic granulomatous disease by gp91-phox expression
Authors: Porter CD , Parkar MH , Collins MK , Levinsky RJ , Kinnon C
Published: October 2019

The primary immunodeficiencies are attractive candidates for the development of gene therapy approaches based on the transduction of hematopoietic cells. We have constructed a high-titer recombinant retrovirus for expression of gp91-phox, deficiencies of which cause the X-linked form of chronic granulomatous disease (X-CGD). We have used this vector to transduce human bone marrow, using either unfractionated mononuclear cells or purified CD34+ cells as targets and evaluated several infection protocols. Efficient gene transfer to progenitors and long-term culture-initiating cells (LTC-IC) was obtained for each target population. Importantly for potential clinical application, this could be achieved without the use of exogenous cytokines or polybrene. Progenitors representing each of the lineages detectable in vitro were transduced at equal efficiencies. The vector was shown partially to restore gp91-phox deficiency and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity in transduced cells derived from X- CGD patients. These data demonstrate that it is possible to transduce primitive human hematopoietic cells efficiently and reconstitute NADPH oxidase.
Persistent clonal excess and skewed T-cell repertoire in T cells from patients with hairy cell leukemia
Authors: Kluin-Nelemans JC , Kester MG , Melenhorst JJ , Landegent JE , van de Corput L , Willemze R , Falkenburg JH
Published: October 2019

Hairy cell leukemia (HCL) is characterized by a severe T-cell-mediated immune deficiency. At the same time, spontaneous T-cell activation is noted when splenic T cells are studied in vivo and in vitro. Therefore, we searched for oligoclonal T-cell populations in the blood and spleens of 25 patients with HCL using a T-cell receptor gamma-polymerase chain reaction (TCR gamma-PCR). Subsequently, in 6 patients, the CDR3 length and conformation from 22 different TCRBV subfamilies were analyzed after PCR amplification of cDNA using TCRBV subfamily-specific primers. T cells from 15 of 25 HCL patients showed clonal excess by the TCR gamma-PCR. In fluorescence-activated cell sorted T-cell subsets, more clonal bands were observed than in the unseparated T cells, with most of these in CD8+ subsets, but also in CD4+, CD3+ gamma/delta+, and a double-negative CD3+ alpha/beta+ subset. In other B-cell malignancies, 6 of 16 samples showed oligoclonal T cells, whereas only 2 of 18 normal spleen and blood samples showed abnormal bands. Analysis of the TCRBV subfamilies disclosed in all 6 HCL patients a markedly abnormal pattern, with many clonal bands in 5 to 15 subfamilies, and absent or abnormal weak patterns in another 1 to 8 subfamilies. In comparison, 6 normal samples (2 spleens and 4 blood samples) showed in only 1 blood donor 1 clonal band. Two patients with active HCL but without infections or treatment were tested several times during the course of the disease and showed a complete identical skewed T-cell repertoire with the same oligoclonal T-cell populations. In conclusion, T cells in the blood and spleen of HCL patients show impressive abnormalities with many oligoclonal T-cell populations and a very restricted and skewed TCRBV repertoire.
Occurrence of the t(2;5)(p23;q35) in non-Hodgkin's lymphoma
Authors: Weisenburger DD , Gordon BG , Vose JM , Bast MA , Chan WC , Greiner TC , Anderson JR , Sanger WG
Published: October 2019

Primary CD30(Ki-1)-positive anaplastic large-cell lymphoma (ALCL) is considered by some to be a distinct clinicopathologic entity associated with the t(2;5) (p23;q35). However, the specificity of t(2;5) for ALCL has not been carefully studied. Therefore, we performed a detailed analysis of all cases of ALCL with abnormal cytogenetics results in the Nebraska Lymphoma Study Group registry, as well as all other cases of non-Hodgkin's lymphoma with t(2;5) in the registry. We found the t(2;5) in only five of 10 cases of ALCL, four of whom were young patients. However, we also found the t(2;5) in 11 other cases of nonanaplastic lymphoma, including eight children with typical peripheral T-cell lymphomas of various types. The t(2;5) was also found in three older adults with B-cell lymphomas of various types. Thus, the t(2;5) was not specific for CD30+ ALCL. However, t(2;5) may define a clinicopathologic entity in children and young adults characterized by variable morphologies with a T-cell or indeterminate phenotype, CD30-positivity, nodal disease with frequent extranodal involvement, advanced stage, and an excellent response to therapy, including bone marrow transplantation for relapsed disease. The clinical relevance of the t(2;5) in older patients requires further study.
Routine bone marrow exam during first remission of acute myeloid leukemia
Authors: Estey E , Pierce S
Published: October 2019

To detect relapse acute myeloid leukemia (AML) treatment protocols have called for bone marrow exams every 2 to 4 months in remission. To investigate the effect of replacing this policy with one calling for marrows only when blood count is abnormal (platelets < 100,000, neutrophils < 1,000, circulating blasts > 0%, unrelated to prior chemotherapy), we reviewed the records of all 444 patients with AML whose disease recurred ( > or = 5% marrow blasts unrelated to prior chemotherapy) for the first time between 1980 and 1995. The 375 patients with adequate follow-up were classified as (1) simultaneous-- blood count abnormal when relapse noted without a normal marrow intervening between first abnormal count and relapse, 289 patients (77% of 375), (2) marrow first--blood count normal when relapse noted, 60 patients (16%), or (3) blood first--a normal marrow intervened between first abnormal blood count and relapse, 26 patients (7%). Interval between marrow exams and blood counts did not differ in the three groups (a 25-patient sample of the 289 patient simultaneous group was analyzed as representative of this group) with marrows done at a median of once monthly and blood counts at a median of once weekly from complete remission (CR) date to relapse date. The three groups also had similar first CR duration, and pretreatment cytogenetics. CR rates following salvage chemotherapy were 32% to 33% in the simultaneous and marrow first groups and 17% in the blood first group. We conclude that routine marrow exams for morphology are not needed in the great majority of AML patients in first CR.