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  • American Society of Hematology  (7)
  • 1
    In: Blood, American Society of Hematology, Vol. 84, No. 1 ( 1994-07-01), p. 53-58
    Abstract: Chronic granulomatous disease (CGD) can result from any of four single gene defects involving components of the superoxide (O2-.)-generating phagocyte NADPH oxidase (phox). The phox transmembrane flavocytochrome b558 is composed of two peptides, gp91phox and p22phox. Mutations of gp91phox cause X-linked CGD, whereas mutations of p22phox cause one of the three autosomal recessive forms of CGD. We used the Maloney leukemia virus-based MFG retrovirus vector to produce replication defective retroviruses encoding gp91phox or p22phox. To maximize viral titer MFG retroviruses do not contain internal promoter or resistance elements. Epstein-Barr virus transformed B-lymphocyte cell lines (EBV- B) derived from normal individuals contain phox components and produce O2-., whereas those derived from CGD patients show the CGD defect. Transduction of gp91phox or p22phox-deficient CGD EBV-B lines resulted in correction of O2-. production from a barely detectable baseline to an average 7.2% and 13.8% of normal control, respectively, without any selective regimen to enrich for transduced cells. CD34+ hematopoietic progenitor cells, the therapeutic target for gene therapy of CGD, were isolated from peripheral blood of CGD patients, transduced with MFG- phox retroviruses, and differentiated in culture to mature phagocytes. Transduction of progenitors corrected the gp91phox (seven patients) and p22phox (two patients) CGD phagocyte oxidase defect to 2.5% and 4.9% of normal O2-. production, respectively, representing an 87-fold and 161- fold increase. These studies show correction of flavocytochrome b558- deficient CGD in primary hematopoietic progenitors, providing a basis for development of gene therapy for the X-linked gp91phox and autosomal p22phox-deficient forms of CGD.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
    RVK:
    RVK:
    Language: English
    Publisher: American Society of Hematology
    Publication Date: 1994
    detail.hit.zdb_id: 1468538-3
    detail.hit.zdb_id: 80069-7
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  • 2
    In: Blood, American Society of Hematology, Vol. 84, No. 1 ( 1994-07-01), p. 53-58
    Abstract: Chronic granulomatous disease (CGD) can result from any of four single gene defects involving components of the superoxide (O2-.)-generating phagocyte NADPH oxidase (phox). The phox transmembrane flavocytochrome b558 is composed of two peptides, gp91phox and p22phox. Mutations of gp91phox cause X-linked CGD, whereas mutations of p22phox cause one of the three autosomal recessive forms of CGD. We used the Maloney leukemia virus-based MFG retrovirus vector to produce replication defective retroviruses encoding gp91phox or p22phox. To maximize viral titer MFG retroviruses do not contain internal promoter or resistance elements. Epstein-Barr virus transformed B-lymphocyte cell lines (EBV- B) derived from normal individuals contain phox components and produce O2-., whereas those derived from CGD patients show the CGD defect. Transduction of gp91phox or p22phox-deficient CGD EBV-B lines resulted in correction of O2-. production from a barely detectable baseline to an average 7.2% and 13.8% of normal control, respectively, without any selective regimen to enrich for transduced cells. CD34+ hematopoietic progenitor cells, the therapeutic target for gene therapy of CGD, were isolated from peripheral blood of CGD patients, transduced with MFG- phox retroviruses, and differentiated in culture to mature phagocytes. Transduction of progenitors corrected the gp91phox (seven patients) and p22phox (two patients) CGD phagocyte oxidase defect to 2.5% and 4.9% of normal O2-. production, respectively, representing an 87-fold and 161- fold increase. These studies show correction of flavocytochrome b558- deficient CGD in primary hematopoietic progenitors, providing a basis for development of gene therapy for the X-linked gp91phox and autosomal p22phox-deficient forms of CGD.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
    RVK:
    RVK:
    Language: English
    Publisher: American Society of Hematology
    Publication Date: 1994
    detail.hit.zdb_id: 1468538-3
    detail.hit.zdb_id: 80069-7
    Library Location Call Number Volume/Issue/Year Availability
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  • 3
    In: Blood, American Society of Hematology, Vol. 87, No. 1 ( 1996-01-01), p. 42-50
    Abstract: Chronic granulomatous disease (CGD) is an inherited hematologic disorder involving failure of phagocytic cell oxidase to produce superoxide (O2-.), resulting in recurrent infections. The success of retrovirus gene therapy for hematopoietic diseases will be limited both by the efficiency of ex vivo transduction of target cells and by the ability of corrected cells to replace uncorrected cells in vivo. Using MFG-based retrovirus vectors containing oxidase genes, we have previously demonstrated in vitro correction of CGD, but transduction rates were low. In the present study we explore a strategy for providing a selective growth advantage to transduced cells, while retaining the single promoter feature of MFG responsible for high virus titer and enhanced protein production. We constructed a bicistronic retrovirus producing a single mRNA encoding both the therapeutic gene for the X-linked form of CGD (X-CGD), gp91phox, and the selectable human multidrug resistance gene, MDR1 linked together by the encephalomyocarditis virus internal ribosome entry site (IRES). As a control we constructed a bicistronic vector with the polio virus IRES element and using the bacterial neomycin resistance gene (neor) as the selective element. In Epstein-Barr virus transformed B (EBV-B) cells from an X-CGD patient, a tissue culture model of CGD, we show correction of the CGD defect and complete normalization of the cell population using either of these vectors and appropriate selection (vincristine for MDR1 and G418 for neor). Using a chemiluminescence assay of O2-. production, populations of cells transduced with either vector demonstrated initial correction levels of from less than 0.1% up to 2.7% of normal EBV-B cell oxidase activity. With either construct, cell growth under appropriate selection enriched the population of transduced cells, resulting in correction of X-CGD EBV-B cells to a level of O2-. production equalling or exceeding that of normal EBV-B cells. These studies show that a therapeutic gene can be linked to a resistance gene by an IRES element, allowing for selective enrichment of cells expressing the therapeutic gene. Furthermore, the use of MDR1 as a selective element in our studies validates an important approach to gene therapy that could allow in vivo selection and is generalizable to a number of therapeutic settings.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
    RVK:
    RVK:
    Language: English
    Publisher: American Society of Hematology
    Publication Date: 1996
    detail.hit.zdb_id: 1468538-3
    detail.hit.zdb_id: 80069-7
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  • 4
    In: Blood, American Society of Hematology, Vol. 110, No. 1 ( 2007-07-01), p. 67-73
    Abstract: Retroviral gene therapy can restore immunity to infants with X-linked severe combined immunodeficiency (XSCID) caused by mutations in the IL2RG gene encoding the common gamma chain (γc) of receptors for interleukins 2 (IL-2), −4, −7, −9, −15, and −21. We investigated the safety and efficacy of gene therapy as salvage treatment for older XSCID children with inadequate immune reconstitution despite prior bone marrow transplant from a parent. Subjects received retrovirus-transduced autologous peripherally mobilized CD34+ hematopoietic cells. T-cell function significantly improved in the youngest subject (age 10 years), and multilineage retroviral marking occurred in all 3 children.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
    RVK:
    RVK:
    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2007
    detail.hit.zdb_id: 1468538-3
    detail.hit.zdb_id: 80069-7
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  • 5
    In: Blood, American Society of Hematology, Vol. 136, No. Supplement 1 ( 2020-11-5), p. 1-2
    Abstract: Introduction Plasmablastic lymphoma (PBL) is a rare, aggressive large cell lymphoma, first described in 1997. PBL is strongly associated with immunodeficient states, such as HIV infection and solid organ transplantation, but up to one third of cases are reported to occur in immunocompetent patients. The pathogenesis of PBL is incompletely understood, though the oncogenic impact of EBV, in particular in the context of dysregulated immune surveillance, together with acquired abnormalities in the MYC pathway appear to play key roles in many cases. Plasma cell markers such as CD138 and CD38 are typically positive, as well as CD30 in a significant subset. Classical B cell markers such as CD20, CD19 and PAX5 are typically absent. The literature on clinical outcomes in PBL is generally limited to small, single-centre case series. Reports describe an aggressive disease of poor prognosis, with median survival of 8 to 15 months, with one series reporting a longer median survival of 32 months. Methods We retrospectively identified patients diagnosed with PBL between 1999 and 2019 from 16 sites across Australia, the United Kingdom and Canada. Patients aged ≥18 years with confirmed tissue diagnosis of PBL at their local treating centre were included. Factors associated with overall survival (OS) were analysed using Cox regression, stratified by site to account for heterogeneity across sites. Risk time for mortality began on the date of diagnosis and ended on the date of death. Patients who were alive, lost to follow-up or transferred to another centre for care, were censored on the date of last follow-up. Risk factors analysed included age, year of diagnosis, HIV status, MYC rearrangement status, CD30 status, lactate dehydrogenase level, disease stage by Lugano consensus criteria, and bone marrow involvement. Results We identified 197 patients with PBL (Table 1). The median age at diagnosis was 55 years (range 18-95) and there was a male predominance (69%). 37% of patients were HIV positive, 56% were HIV negative and 7% were either not tested or had missing results. Other immunosuppressive risk factors included solid organ transplant, allogeneic stem cell transplant (SCT), and immunosuppressive medication. No immunodeficient state was detected in 44%. Fifty per cent of patients were stage IV at diagnosis. Fifty-four per cent were staged using PET/CT. The median follow-up time from diagnosis was 1.36 years, with the longest follow up out to 18.4 years. There were 87 deaths (44%). For patients receiving first-line treatment with curative intent, the rate of complete remission was 57% (103 of 181 patients). Most patients (53%) received CHOP (cyclophosphamide, doxorubicin, vincristine, prednisolone)-based chemotherapy as first line, and 27% treatment of higher intensity than CHOP. Rituximab was administered to 20% and 10% were exposed to proteasome inhibitors as part of first line therapy. Five percent of patients underwent autologous SCT in first remission, and a further 5% after first relapse or later. The median survival time was 4.8 years, with a 5-year OS of 49% and 10-year OS of 45% (figure 1). In multivariate analysis the only adverse factors associated with OS were bone marrow involvement and stage IV disease. Patients without bone marrow involvement at diagnosis had improved OS, compared to those who did (hazard ratio (HR) 0.36, 95%CI 0.18-0.72, p=0.004) (figure 2). There was an increasing trend for mortality with higher disease stages (p-trend=0.002). The median survival was 14.1 years for stage I, 10.7 years for stage II, 5.1 years for stage III and 1.2 years for stage IV. However, only stage IV disease was independently associated with inferior OS in multivariate analysis (HR 2.93, 95%CI 1.43-6.00, p=0.003) (figure 3). OS did not change depending upon year of diagnosis. Conclusion We report a multinational retrospective cohort of patients diagnosed with PBL and to our knowledge the largest single series of PBL to date. OS was longer than previously published data, particularly in patients with early-stage disease. However, patients with stage IV disease and baseline bone marrow involvement had inferior OS. HIV infection did not affect outcome. These findings suggest that baseline bone marrow biopsy and PET staging are useful prognostic tools. There is also an ongoing need for the evaluation of the predictive value of PET imaging and novel agents in PBL, especially in higher-risk disease. Disclosures Di Ciaccio: Jansen: Honoraria, Other: travel and accomodation grant. Cwynarski:Takeda: Consultancy, Other: Conference/travel support; Roche: Consultancy, Other: Conference/travel support. Burton:Celgene: Honoraria; Leeds Teaching Hospitals NHS Trust: Current Employment; Takeda: Honoraria, Other: Travel Support; BMS: Honoraria; Roche: Honoraria, Other: Travel Support. Kuruvilla:Antengene: Honoraria; Janssen: Honoraria, Research Funding; Roche: Consultancy, Honoraria, Research Funding; Seattle Genetics: Consultancy, Honoraria; Karyopharm: Consultancy, Honoraria; Gilead: Consultancy, Honoraria; AbbVie: Consultancy; AstraZeneca Pharmaceuticals LP: Honoraria, Research Funding; Merck: Consultancy, Honoraria; Celgene Corporation: Honoraria; Amgen: Honoraria; TG Therapeutics: Honoraria; Pfizer: Honoraria; Novartis: Honoraria; Bristol-Myers Squibb Company: Consultancy. McKay:Greater Glasgow and Clyde Health Board: Current Employment; Roche, Gilead, Takeda, Janssen: Other: For lectures etc; Roche: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees; Gilead: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; BeiGene: Membership on an entity's Board of Directors or advisory committees; Janssen: Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company), Speakers Bureau; TAKEDA: Membership on an entity's Board of Directors or advisory committees, Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company), Speakers Bureau. Linton:BeiGene: Consultancy, Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other: Conference/travel support; Roche: Consultancy, Speakers Bureau; Gilead: Membership on an entity's Board of Directors or advisory committees; Karyopharm: Membership on an entity's Board of Directors or advisory committees; Takeda: Consultancy, Honoraria, Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company), Patents & Royalties; Janssen: Consultancy, Honoraria, Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company); Hartley-Taylor: Honoraria; The Christie NHS Foundation Trust and The University of Manchester: Current Employment. Manos:Bristol-Myers Squibb: Other: Conference sponsorship. Hamad:Abbvie: Honoraria; Novartis: Honoraria.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
    RVK:
    RVK:
    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2020
    detail.hit.zdb_id: 1468538-3
    detail.hit.zdb_id: 80069-7
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  • 6
    In: Blood, American Society of Hematology, Vol. 94, No. 7 ( 1999-10-01), p. 2271-2286
    Abstract: Optimization of mobilization, harvest, and transduction of hematopoietic stem cells is critical to successful stem cell gene therapy. We evaluated the utility of a novel protocol involving Flt3-ligand (Flt3-L) and granulocyte colony-stimulating factor (G-CSF) mobilization of peripheral blood stem cells and retrovirus transduction using hematopoietic growth factors to introduce a reporter gene, murine CD24 (mCD24), into hematopoietic stem cells in nonhuman primates. Rhesus macaques were treated with Flt3-L (200 μg/kg) and G-CSF (20 μg/kg) for 7 days and autologous CD34+ peripheral blood stem cells harvested by leukapheresis. CD34+ cells were transduced with an MFGS-based retrovirus vector encoding mCD24 using 4 daily transductions with centrifugations in the presence of Flt3-L (100 ng/mL), human stem cell factor (50 ng/mL), and PIXY321 (50 ng/mL) in serum-free medium. An important and novel feature of this study is that enhanced in vivo engraftment of transduced stem cells was achieved by conditioning the animals with a low-morbidity regimen of sublethal irradiation (320 to 400 cGy) on the day of transplantation. Engraftment was monitored sequentially in the bone marrow and blood using both multiparameter flow cytometry and semi-quantitative DNA polymerase chain reaction (PCR). Our data show successful and persistent engraftment of transduced primitive progenitors capable of giving rise to marked cells of multiple hematopoietic lineages, including granulocytes, monocytes, and B and T lymphocytes. At 4 to 6 weeks posttransplantation, 47% ± 32% (n = 4) of granulocytes expressed mCD24 antigen at the cell surface. Peak in vivo levels of genetically modified peripheral blood lymphocytes approached 35% ± 22% (n = 4) as assessed both by flow cytometry and PCR 6 to 10 weeks posttransplantation. In addition, naı̈ve (CD45RA+and CD62L+) CD4+ and CD8+cells were the predominant phenotype of the marked CD3+ T cells detected at early time points. A high level of marking persisted at between 10% and 15% of peripheral blood leukocytes for 4 months and at lower levels past 6 months in some animals. A cytotoxic T-lymphocyte response against mCD24 was detected in only 1 animal. This degree of persistent long-lived, high-level gene marking of multiple hematopoietic lineages, including naı̈ve T cells, using a nonablative marrow conditioning regimen represents an important step toward the ultimate goal of high-level permanent transduced gene expression in stem cells.
    Type of Medium: Online Resource
    ISSN: 1528-0020 , 0006-4971
    RVK:
    RVK:
    Language: English
    Publisher: American Society of Hematology
    Publication Date: 1999
    detail.hit.zdb_id: 1468538-3
    detail.hit.zdb_id: 80069-7
    Library Location Call Number Volume/Issue/Year Availability
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  • 7
    In: Blood, American Society of Hematology, Vol. 87, No. 1 ( 1996-01-01), p. 42-50
    Abstract: Chronic granulomatous disease (CGD) is an inherited hematologic disorder involving failure of phagocytic cell oxidase to produce superoxide (O2-.), resulting in recurrent infections. The success of retrovirus gene therapy for hematopoietic diseases will be limited both by the efficiency of ex vivo transduction of target cells and by the ability of corrected cells to replace uncorrected cells in vivo. Using MFG-based retrovirus vectors containing oxidase genes, we have previously demonstrated in vitro correction of CGD, but transduction rates were low. In the present study we explore a strategy for providing a selective growth advantage to transduced cells, while retaining the single promoter feature of MFG responsible for high virus titer and enhanced protein production. We constructed a bicistronic retrovirus producing a single mRNA encoding both the therapeutic gene for the X-linked form of CGD (X-CGD), gp91phox, and the selectable human multidrug resistance gene, MDR1 linked together by the encephalomyocarditis virus internal ribosome entry site (IRES). As a control we constructed a bicistronic vector with the polio virus IRES element and using the bacterial neomycin resistance gene (neor) as the selective element. In Epstein-Barr virus transformed B (EBV-B) cells from an X-CGD patient, a tissue culture model of CGD, we show correction of the CGD defect and complete normalization of the cell population using either of these vectors and appropriate selection (vincristine for MDR1 and G418 for neor). Using a chemiluminescence assay of O2-. production, populations of cells transduced with either vector demonstrated initial correction levels of from less than 0.1% up to 2.7% of normal EBV-B cell oxidase activity. With either construct, cell growth under appropriate selection enriched the population of transduced cells, resulting in correction of X-CGD EBV-B cells to a level of O2-. production equalling or exceeding that of normal EBV-B cells. These studies show that a therapeutic gene can be linked to a resistance gene by an IRES element, allowing for selective enrichment of cells expressing the therapeutic gene. Furthermore, the use of MDR1 as a selective element in our studies validates an important approach to gene therapy that could allow in vivo selection and is generalizable to a number of therapeutic settings.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
    RVK:
    RVK:
    Language: English
    Publisher: American Society of Hematology
    Publication Date: 1996
    detail.hit.zdb_id: 1468538-3
    detail.hit.zdb_id: 80069-7
    Library Location Call Number Volume/Issue/Year Availability
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