Direct evaluation of radiation damage in human hematopoietic progenitor cells in vivo

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Kyoizumi, Seishi; McCune, J.M.; Namikawa, Reiko

1994-01-01

We have developed techniques by which normal functional elements of human bone marrow can be implanted into immunodeficient C.B-17 scid/scid (SCID) mice. Afterward, long-term multilineage human hematopoiesis is sustained in vivo. We evaluated the effect of irradiation on the function of human bone marrow with this in vivo model. After whole-body X irradiation of the engrafted animals, it was determined that the D 0 value of human committed progenitor cells within the human marrow was 1.00 ± 0.09 (SEM) Gy for granulocyte-macrophage colony-forming units (CFU-GM) and 0.74 ± 0.12 Gy for erythroidburst-forming units (BFU-E). The effects of irradiation on the hematopoietic elements were reduced when the radioprotective agent WR-2721 was administered prior to irradiation. After low-dose irradiation, recovery of human granulocyte colony-stimulating factor (G-CSF). This small animal model may prove amenable for the analysis of the risk of the exposure of humans to irradiation as well as for the development of new modalities for the prevention and treatment of radiation-induced hematopoietic damage. 41 refs., 5 figs., 1 tab

Long-term expression of human adenosine deaminase in mice transplanted with retrovirus-infected hematopoietic stem cells

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Lim, B.; Apperley, J.F.; Orkin, S.H.; Williams, D.A.

1989-01-01

Long-term stable expression of foreign genetic sequences transferred into hematopoietic stem cells by using retroviral vectors constitutes a relevant model for somatic gene therapy. Such stability of expression may depend on vector design, including the presence or absence of specific sequences within the vector, in combination with the nature and efficiency of infection of the hematopoietic target cells. The authors have previously reported successful transfer of human DNA encoding adenosine deaminase (ADA) into CFU-S (colony-forming unit-spleen) stem cells using simplified recombinant retroviral vectors. Human ADA was expressed in CFU-S-derived spleen colonies at levels near to endogenous enzyme. However, because of the lack of an efficient dominant selectable marker and low recombinant viral titers, stability of long-term expression of human ADA was not examined. They report here the development of an efficient method of infection of hematopoietic stem cells (HSC) without reliance on in vitro selection. Peripheral blood samples of 100% of mice transplanted with HSC infected by this protocol exhibit expression of human ADA 30 days after transplantation. Some mice (6 of 13) continue to express human ADA in all lineages after complete hematopoietic reconstitution (4 months). The use of recombinant retroviral vectors that efficiently transfer human ADA cDNA into HSC leading to stable expression of functional ADA in reconstituted mice, provides an experimental framework for future development of approaches to somatic gene therapy

Hematopoietic defects in response to reduced Arhgap21

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Juliana Xavier-Ferrucio

2018-01-01

Full Text Available Arhgap21 is a member of the Rho GTPase activating protein (RhoGAP family, which function as negative regulators of Rho GTPases. Arhgap21 has been implicated in adhesion and migration of cancer cells. However, the role of Arhgap21 has never been investigated in hematopoietic cells. Herein, we evaluated functional aspects of hematopoietic stem and progenitor cells (HSPC using a haploinsufficient (Arhgap21+/− mouse. Our results show that Arhgap21+/− mice have an increased frequency of phenotypic HSC, impaired ability to form progenitor colonies in vitro and decreased hematopoietic engraftment in vivo, along with a decrease in LSK cell frequency during serial bone marrow transplantation. Arhgap21+/− hematopoietic progenitor cells have impaired adhesion and enhanced mobilization of immature LSK and myeloid progenitors. Arhgap21+/− mice also exhibit reduced erythroid commitment and differentiation, which was recapitulated in human primary cells, in which knockdown of ARHGAP21 in CMP and MEP resulted in decreased erythroid commitment. Finally, we observed enhanced RhoC activity in the bone marrow cells of Arhgap21+/− mice, indicating that Arhgap21 functions in hematopoiesis may be at least partially mediated by RhoC inactivation. Keywords: Arhgap21, Hematopoiesis, Erythroid cells, Hematopoietic stem and progenitor cells, Fate decision

Knockdown of Fanconi anemia genes in human embryonic stem cells reveals early developmental defects in the hematopoietic lineage.

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Tulpule, Asmin; Lensch, M William; Miller, Justine D; Austin, Karyn; D'Andrea, Alan; Schlaeger, Thorsten M; Shimamura, Akiko; Daley, George Q

2010-04-29

Fanconi anemia (FA) is a genetically heterogeneous, autosomal recessive disorder characterized by pediatric bone marrow failure and congenital anomalies. The effect of FA gene deficiency on hematopoietic development in utero remains poorly described as mouse models of FA do not develop hematopoietic failure and such studies cannot be performed on patients. We have created a human-specific in vitro system to study early hematopoietic development in FA using a lentiviral RNA interference (RNAi) strategy in human embryonic stem cells (hESCs). We show that knockdown of FANCA and FANCD2 in hESCs leads to a reduction in hematopoietic fates and progenitor numbers that can be rescued by FA gene complementation. Our data indicate that hematopoiesis is impaired in FA from the earliest stages of development, suggesting that deficiencies in embryonic hematopoiesis may underlie the progression to bone marrow failure in FA. This work illustrates how hESCs can provide unique insights into human development and further our understanding of genetic disease.

Increasing Hematopoietic Stem Cell Yield to Develop Mice with Human Immune Systems

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Juan-Carlos Biancotti

2013-01-01

Full Text Available Hematopoietic stem cells (HSCs are unique in their capacity to give rise to all mature cells of the immune system. For years, HSC transplantation has been used for treatment of genetic and neoplastic diseases of the hematopoietic and immune systems. The sourcing of HSCs from human umbilical cord blood has salient advantages over isolation from mobilized peripheral blood. However, poor sample yield has prompted development of methodologies to expand HSCs ex vivo. Cytokines, trophic factors, and small molecules have been variously used to promote survival and proliferation of HSCs in culture, whilst strategies to lower the concentration of inhibitors in the culture media have recently been applied to promote HSC expansion. In this paper, we outline strategies to expand HSCs in vitro, and to improve engraftment and reconstitution of human immune systems in immunocompromised mice. To the extent that these “humanized” mice are representative of the endogenous human immune system, they will be invaluable tools for both basic science and translational medicine.

A novel serum-free monolayer culture for orderly hematopoietic differentiation of human pluripotent cells via mesodermal progenitors.

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Akira Niwa

Full Text Available Elucidating the in vitro differentiation of human embryonic stem (ES and induced pluripotent stem (iPS cells is important for understanding both normal and pathological hematopoietic development in vivo. For this purpose, a robust and simple hematopoietic differentiation system that can faithfully trace in vivo hematopoiesis is necessary. In this study, we established a novel serum-free monolayer culture that can trace the in vivo hematopoietic pathway from ES/iPS cells to functional definitive blood cells via mesodermal progenitors. Stepwise tuning of exogenous cytokine cocktails induced the hematopoietic mesodermal progenitors via primitive streak cells. These progenitors were then differentiated into various cell lineages depending on the hematopoietic cytokines present. Moreover, single cell deposition assay revealed that common bipotential hemoangiogenic progenitors were induced in our culture. Our system provides a new, robust, and simple method for investigating the mechanisms of mesodermal and hematopoietic differentiation.

Tfe3 expression is closely associated to macrophage terminal differentiation of human hematopoietic myeloid precursors

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Zanocco-Marani, Tommaso; Vignudelli, Tatiana; Gemelli, Claudia; Pirondi, Sara; Testa, Anna; Montanari, Monica; Parenti, Sandra; Tenedini, Elena; Grande, Alexis; Ferrari, Sergio

2006-01-01

The MItf-Tfe family of basic helix-loop-helix leucine zipper (bHLH-Zip) transcription factors encodes four family members: MItf, Tfe3, TfeB and TfeC. In vitro, each protein of the family binds DNA in a homo- or heterodimeric form with other family members. Tfe3 is involved in chromosomal translocations recurrent in different tumors and it has been demonstrated, by in vivo studies, that it plays, redundantly with MItf, an important role in the process of osteoclast formation, in particular during the transition from mono-nucleated to multi-nucleated osteoclasts. Since mono-nucleated osteoclasts derive from macrophages we investigated whether Tfe3 might play a role upstream during hematopoietic differentiation. Here we show that Tfe3 is able to induce mono-macrophagic differentiation of U937 cells, in association with a decrease of cell proliferation and an increase of apoptosis. We also show that Tfe3 does not act physiologically during commitment of CD34+ hematopoietic stem cells (HSCs), since it is not able to direct HSCs toward a specific lineage as observed by clonogenic assay, but is a strong actor of terminal differentiation since it allows human primary myeloblasts' maturation toward the macrophage lineage

Allogeneic hematopoietic stem cell transplantation in children with primary immunodeficiencies: Hospital Israelita Albert Einstein experience

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Juliana Folloni Fernandes

2011-06-01

Full Text Available Objective: To report the experience of a tertiary care hospital withallogeneic hematopoietic stem cell transplantation in children withprimary immunodeficiencies. Methods: Seven patients with primaryimmunodeficiencies (severe combined immunodeficiency: n = 2;combined immunodeficiency: n = 1; chronic granulomatous disease:n = 1; hyper-IgM syndrome: n = 2; and IPEX syndrome: n = 1who underwent eight hematopoietic stem cell transplants (HSCTin a single center, from 2007 to 2010, were studied. Results: Twopatients received transplants from HLA-identical siblings; the othersix transplants were done with unrelated donors (bone marrow: n= 1; cord blood: n = 5. All patients had pre-existing infectionsbefore hematopoietic stem cell transplants. One patient receivedonly anti-thymocyte globulin prior to transplant, three transplantswere done with reduced intensity conditioning regimens and fourtransplants were done after myeloablative therapy. Two patientswere not evaluable for engraftment due to early death. Three patientsengrafted, two had primary graft failure and one received a secondtransplant with posterior engraftment. Two patients died of regimenrelated toxicity (hepatic sinusoidal obstruction syndrome; one patient died of progressive respiratory failure due to Parainfluenza infection diagnosed prior to transplant. Four patients are alive and well from 60 days to 14 months after transplant. Conclusion: Patients’ status prior to transplant is the most important risk factor on the outcome of hematopoietic stem cell transplants in the treatment of these diseases. Early diagnosis and the possibility of a faster referral of these patients for treatment in reference centers may substantially improve their survival and quality of life.

Generating autologous hematopoietic cells from human-induced pluripotent stem cells through ectopic expression of transcription factors.

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Hwang, Yongsung; Broxmeyer, Hal E; Lee, Man Ryul

2017-07-01

Hematopoietic cell transplantation (HCT) is a successful treatment modality for patients with malignant and nonmalignant disorders, usually when no other treatment option is available. The cells supporting long-term reconstitution after HCT are the hematopoietic stem cells (HSCs), which can be limited in numbers. Moreover, finding an appropriate human leukocyte antigen-matched donor can be problematic. If HSCs can be stably produced in large numbers from autologous or allogeneic cell sources, it would benefit HCT. Induced pluripotent stem cells (iPSCs) established from patients' own somatic cells can be differentiated into hematopoietic cells in vitro. This review will highlight recent methods for regulating human (h) iPSC production of HSCs and more mature blood cells. Advancements in transcription factor-mediated regulation of the developmental stages of in-vivo hematopoietic lineage commitment have begun to provide an understanding of the molecular mechanism of hematopoiesis. Such studies involve not only directed differentiation in which transcription factors, specifically expressed in hematopoietic lineage-specific cells, are overexpressed in iPSCs, but also direct conversion in which transcription factors are introduced into patient-derived somatic cells which are dedifferentiated to hematopoietic cells. As iPSCs derived from patients suffering from genetically mutated diseases would express the same mutated genetic information, CRISPR-Cas9 gene editing has been utilized to differentiate genetically corrected iPSCs into normal hematopoietic cells. IPSCs provide a model for molecular understanding of disease, and also may function as a cell population for therapy. Efficient differentiation of patient-specific iPSCs into HSCs and progenitor cells is a potential means to overcome limitations of such cells for HCT, as well as for providing in-vitro drug screening templates as tissue-on-a-chip models.

Different Motile Behaviors of Human Hematopoietic Stem versus Progenitor Cells at the Osteoblastic Niche

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Katie Foster

2015-11-01

Full Text Available Despite advances in our understanding of interactions between mouse hematopoietic stem cells (HSCs and their niche, little is known about communication between human HSCs and the microenvironment. Using a xenotransplantation model and intravital imaging, we demonstrate that human HSCs display distinct motile behaviors to their hematopoietic progenitor cell (HPC counterparts, and the same pattern can be found between mouse HSCs and HPCs. HSCs become significantly less motile after transplantation, while progenitor cells remain motile. We show that human HSCs take longer to find their niche than previously expected and suggest that the niche be defined as the position where HSCs stop moving. Intravital imaging is the only technique to determine where in the bone marrow stem cells stop moving, and future analyses should focus on the environment surrounding the HSC at this point.

Induced Pluripotent Stem Cells: A novel frontier in the study of human primary immunodeficiencies

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Pessach, Itai M.; Ordovas-Montanes, Jose; Zhang, Shen-Ying; Casanova, Jean-Laurent; Giliani, Silvia; Gennery, Andrew R.; Al-Herz, Waleed; Manos, Philip D.; Schlaeger, Thorsten M.; Park, In-Hyun; Rucci, Francesca; Agarwal, Suneet; Mostoslavsky, Gustavo; Daley, George Q.; Notarangelo, Luigi D.

2010-01-01

Background The novel ability to epigenetically reprogram somatic cells into induced pluripotent stem cells through the exogenous expression of transcription promises to revolutionize the study of human diseases. Objective Here we report on the generation of 25 induced pluripotent stem cell lines from 6 patients with various forms of Primary Immunodeficiencies, affecting adaptive and/or innate immunity. Methods Patients’ dermal fibroblasts were reprogrammed by expression of four transcription factors, OCT4, SOX2, KLF4, and c-MYC using a single excisable polycistronic lentiviral vector. Results Induced pluripotent stem cells derived from patients with primary immunodeficiencies show a stemness profile that is comparable to that observed in human embryonic stem cells. Following in vitro differentiation into embryoid bodies, pluripotency of the patient-derived indiced pluripotent stem cells lines was demonstrated by expression of genes characteristic of each of the three embryonic layers. We have confirmed the patient-specific origin of the induced pluripotent stem cell lines, and ascertained maintenance of karyotypic integrity. Conclusion By providing a limitless source of diseased stem cells that can be differentiated into various cell types in vitro, the repository of induced pluripotent stem cell lines from patients with primary immunodeficiencies represents a unique resource to investigate the pathophysiology of hematopoietic and extra-hematopoietic manifestations of these diseases, and may assist in the development of novel therapeutic approaches based on gene correction. PMID:21185069

The human ankyrin 1 promoter insulator sustains gene expression in a β-globin lentiviral vector in hematopoietic stem cells

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Zulema Romero

Full Text Available Lentiviral vectors designed for the treatment of the hemoglobinopathies require the inclusion of regulatory and strong enhancer elements to achieve sufficient expression of the β-globin transgene. Despite the inclusion of these elements, the efficacy of these vectors may be limited by transgene silencing due to the genomic environment surrounding the integration site. Barrier insulators can be used to give more consistent expression and resist silencing even with lower vector copies. Here, the barrier activity of an insulator element from the human ankyrin-1 gene was analyzed in a lentiviral vector carrying an antisickling human β-globin gene. Inclusion of a single copy of the Ankyrin insulator did not affect viral titer, and improved the consistency of expression from the vector in murine erythroleukemia cells. The presence of the Ankyrin insulator element did not change transgene expression in human hematopoietic cells in short-term erythroid culture or in vivo in primary murine transplants. However, analysis in secondary recipients showed that the lentiviral vector with the Ankyrin element preserved transgene expression, whereas expression from the vector lacking the Ankyrin insulator decreased in secondary recipients. These studies demonstrate that the Ankyrin insulator may improve long-term β-globin expression in hematopoietic stem cells for gene therapy of hemoglobinopathies.

The thrombopoietin receptor, c-Mpl, is a selective surface marker for human hematopoietic stem cells

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Kerr William G

2006-02-01

Full Text Available Abstract Background Thrombopoietin (TPO, the primary cytokine regulating megakaryocyte proliferation and differentiation, exerts significant influence on other hematopoietic lineages as well, including erythroid, granulocytic and lymphoid lineages. We previously demonstrated that the receptor for TPO, c-mpl, is expressed by a subset of human adult bone marrow hematopoietic stem/progenitor cells (HSC/PC that are enriched for long-term multilineage repopulating ability in the SCID-hu Bone in vivo model of human hematopoiesis. Methods Here, we employ flow cytometry and an anti-c-mpl monoclonal antibody to comprehensively define the surface expression pattern of c-mpl in four differentiation stages of human CD34+ HSC/PC (I: CD34+38--, II: CD34+38dim, III: CD34+38+, IV: CD34dim38+ for the major sources of human HSC: fetal liver (FL, umbilical cord blood (UCB, adult bone marrow (ABM, and cytokine-mobilized peripheral blood stem cells (mPBSC. We use a surrogate in vivo model of human thymopoiesis, SCID-hu Thy/Liv, to compare the capacity of c-mpl+ vs. c-mpl-- CD34+38--/dim HSC/PC for thymocyte reconstitution. Results For all tissue sources, the percentage of c-mpl+ cells was significantly highest in stage I HSC/PC (FL 72 ± 10%, UCB 67 ± 19%, ABM 82 ± 16%, mPBSC 71 ± 15%, and decreased significantly through stages II, III, and IV ((FL 3 ± 3%, UCB 8 ± 13%, ABM 0.6 ± 0.6%, mPBSC 0.2 ± 0.1% [ANOVA: P I, decreasing through stage IV [ANOVA: P + cells [P = 0.89] or intensity of c-mpl expression [P = 0.21]. Primary Thy/Liv grafts injected with CD34+38--/dimc-mpl+ cells showed slightly higher levels of donor HLA+ thymocyte reconstitution vs. CD34+38--/dimc-mpl---injected grafts and non-injected controls (c-mpl+ vs. c-mpl--: CD2+ 6.8 ± 4.5% vs. 2.8 ± 3.3%, CD4+8-- 54 ± 35% vs. 31 ± 29%, CD4--8+ 29 ± 19% vs. 18 ± 14%. Conclusion These findings support the hypothesis that the TPO receptor, c-mpl, participates in the regulation of primitive human HSC

Therapeutic gene editing in CD34+ hematopoietic progenitors from Fanconi anemia patients.

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Diez, Begoña; Genovese, Pietro; Roman-Rodriguez, Francisco J; Alvarez, Lara; Schiroli, Giulia; Ugalde, Laura; Rodriguez-Perales, Sandra; Sevilla, Julian; Diaz de Heredia, Cristina; Holmes, Michael C; Lombardo, Angelo; Naldini, Luigi; Bueren, Juan Antonio; Rio, Paula

2017-11-01

Gene targeting constitutes a new step in the development of gene therapy for inherited diseases. Although previous studies have shown the feasibility of editing fibroblasts from Fanconi anemia (FA) patients, here we aimed at conducting therapeutic gene editing in clinically relevant cells, such as hematopoietic stem cells (HSCs). In our first experiments, we showed that zinc finger nuclease (ZFN)-mediated insertion of a non-therapeutic EGFP-reporter donor in the AAVS1 "safe harbor" locus of FA-A lymphoblastic cell lines (LCLs), indicating that FANCA is not essential for the editing of human cells. When the same approach was conducted with therapeutic FANCA donors, an efficient phenotypic correction of FA-A LCLs was obtained. Using primary cord blood CD34 + cells from healthy donors, gene targeting was confirmed not only in in vitro cultured cells, but also in hematopoietic precursors responsible for the repopulation of primary and secondary immunodeficient mice. Moreover, when similar experiments were conducted with mobilized peripheral blood CD34 + cells from FA-A patients, we could demonstrate for the first time that gene targeting in primary hematopoietic precursors from FA patients is feasible and compatible with the phenotypic correction of these clinically relevant cells. © 2017 The Authors. Published under the terms of the CC BY 4.0 license.

Role of reactive oxygen species in the radiation response of human hematopoietic stem/progenitor cells.

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Masaru Yamaguchi

Full Text Available Hematopoietic stem/progenitor cells (HSPCs, which are present in small numbers in hematopoietic tissues, can differentiate into all hematopoietic lineages and self-renew to maintain their undifferentiated phenotype. HSPCs are extremely sensitive to oxidative stressors such as anti-cancer agents, radiation, and the extensive accumulation of reactive oxygen species (ROS. The quiescence and stemness of HSPCs are maintained by the regulation of mitochondrial biogenesis, ROS, and energy homeostasis in a special microenvironment called the stem cell niche. The present study evaluated the relationship between the production of intracellular ROS and mitochondrial function during the proliferation and differentiation of X-irradiated CD34(+ cells prepared from human placental/umbilical cord blood HSPCs. Highly purified CD34(+ HSPCs exposed to X-rays were cultured in liquid and semi-solid medium supplemented with hematopoietic cytokines. X-irradiated CD34(+ HSPCs treated with hematopoietic cytokines, which promote their proliferation and differentiation, exhibited dramatically suppressed cell growth and clonogenic potential. The amount of intracellular ROS in X-irradiated CD34(+ HSPCs was significantly higher than that in non-irradiated cells during the culture period. However, neither the intracellular mitochondrial content nor the mitochondrial superoxide production was elevated in X-irradiated CD34(+ HSPCs compared with non-irradiated cells. Radiation-induced gamma-H2AX expression was observed immediately following exposure to 4 Gy of X-rays and gradually decreased during the culture period. This study reveals that X-irradiation can increase persistent intracellular ROS in human CD34(+ HSPCs, which may not result from mitochondrial ROS due to mitochondrial dysfunction, and indicates that substantial DNA double-strand breakage can critically reduce the stem cell function.

Zinc finger protein 521 antagonizes early B-cell factor 1 and modulates the B-lymphoid differentiation of primary hematopoietic progenitors.

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Mega, Tiziana; Lupia, Michela; Amodio, Nicola; Horton, Sarah J; Mesuraca, Maria; Pelaggi, Daniela; Agosti, Valter; Grieco, Michele; Chiarella, Emanuela; Spina, Raffaella; Moore, Malcolm A S; Schuringa, Jan Jacob; Bond, Heather M; Morrone, Giovanni

2011-07-01

Zinc finger protein 521 (EHZF/ZNF521) is a multi-functional transcription co-factor containing 30 zinc fingers and an amino-terminal motif that binds to the nucleosome remodelling and histone deacetylase (NuRD) complex. ZNF521 is believed to be a relevant player in the regulation of the homeostasis of the hematopoietic stem/progenitor cell compartment, however the underlying molecular mechanisms are still largely unknown. Here, we show that this protein plays an important role in the control of B-cell development by inhibiting the activity of early B-cell factor-1 (EBF1), a master factor in B-lineage specification. In particular, our data demonstrate that: (1) ZNF521 binds to EBF1 via its carboxyl-terminal portion and this interaction is required for EBF1 inhibition; (2) NuRD complex recruitment by ZNF521 is not essential for the inhibition of transactivation of EBF1-dependent promoters; (3) ZNF521 represses EBF1 target genes in a human B-lymphoid molecular context; and (4) RNAi-mediated silencing of ZNF521/Zfp521 in primary human and murine hematopoietic progenitors strongly enhances the generation of B-lymphocytes in vitro. Taken together, our data indicate that ZNF521 can antagonize B-cell development and lend support to the notion that it may contribute to conserve the multipotency of primitive lympho-myeloid progenitors by preventing or delaying their EBF1-driven commitment toward the B-cell lineage.

UMG Lenti: novel lentiviral vectors for efficient transgene- and reporter gene expression in human early hematopoietic progenitors.

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Emanuela Chiarella

Full Text Available Lentiviral vectors are widely used to investigate the biological properties of regulatory proteins and/or of leukaemia-associated oncogenes by stably enforcing their expression in hematopoietic stem and progenitor cells. In these studies it is critical to be able to monitor and/or sort the infected cells, typically via fluorescent proteins encoded by the modified viral genome. The most popular strategy to ensure co-expression of transgene and reporter gene is to insert between these cDNAs an IRES element, thus generating bi-cistronic mRNAs whose transcription is driven by a single promoter. However, while the product of the gene located upstream of the IRES is generally abundantly expressed, the translation of the downstream cDNA (typically encoding the reporter protein is often inconsistent, which hinders the detection and the isolation of transduced cells. To overcome these limitations, we developed novel lentiviral dual-promoter vectors (named UMG-LV5 and -LV6 where transgene expression is driven by the potent UBC promoter and that of the reporter protein, EGFP, by the minimal regulatory element of the WASP gene. These vectors, harboring two distinct transgenes, were tested in a variety of human haematopoietic cell lines as well as in primary human CD34+ cells in comparison with the FUIGW vector that contains the expression cassette UBC-transgene-IRES-EGFP. In these experiments both UMG-LV5 and UMG-LV6 yielded moderately lower transgene expression than FUIGW, but dramatically higher levels of EGFP, thereby allowing the easy distinction between transduced and non-transduced cells. An additional construct was produced, in which the cDNA encoding the reporter protein is upstream, and the transgene downstream of the IRES sequence. This vector, named UMG-LV11, proved able to promote abundant expression of both transgene product and EGFP in all cells tested. The UMG-LVs represent therefore useful vectors for gene transfer-based studies in

UMG Lenti: novel lentiviral vectors for efficient transgene- and reporter gene expression in human early hematopoietic progenitors.

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Chiarella, Emanuela; Carrà, Giovanna; Scicchitano, Stefania; Codispoti, Bruna; Mega, Tiziana; Lupia, Michela; Pelaggi, Daniela; Marafioti, Maria G; Aloisio, Annamaria; Giordano, Marco; Nappo, Giovanna; Spoleti, Cristina B; Grillone, Teresa; Giovannone, Emilia D; Spina, Raffaella; Bernaudo, Francesca; Moore, Malcolm A S; Bond, Heather M; Mesuraca, Maria; Morrone, Giovanni

2014-01-01

Lentiviral vectors are widely used to investigate the biological properties of regulatory proteins and/or of leukaemia-associated oncogenes by stably enforcing their expression in hematopoietic stem and progenitor cells. In these studies it is critical to be able to monitor and/or sort the infected cells, typically via fluorescent proteins encoded by the modified viral genome. The most popular strategy to ensure co-expression of transgene and reporter gene is to insert between these cDNAs an IRES element, thus generating bi-cistronic mRNAs whose transcription is driven by a single promoter. However, while the product of the gene located upstream of the IRES is generally abundantly expressed, the translation of the downstream cDNA (typically encoding the reporter protein) is often inconsistent, which hinders the detection and the isolation of transduced cells. To overcome these limitations, we developed novel lentiviral dual-promoter vectors (named UMG-LV5 and -LV6) where transgene expression is driven by the potent UBC promoter and that of the reporter protein, EGFP, by the minimal regulatory element of the WASP gene. These vectors, harboring two distinct transgenes, were tested in a variety of human haematopoietic cell lines as well as in primary human CD34+ cells in comparison with the FUIGW vector that contains the expression cassette UBC-transgene-IRES-EGFP. In these experiments both UMG-LV5 and UMG-LV6 yielded moderately lower transgene expression than FUIGW, but dramatically higher levels of EGFP, thereby allowing the easy distinction between transduced and non-transduced cells. An additional construct was produced, in which the cDNA encoding the reporter protein is upstream, and the transgene downstream of the IRES sequence. This vector, named UMG-LV11, proved able to promote abundant expression of both transgene product and EGFP in all cells tested. The UMG-LVs represent therefore useful vectors for gene transfer-based studies in hematopoietic stem and

Comprehensive evaluation of leukocyte lineage derived from human hematopoietic cells in humanized mice.

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Takahashi, Masayuki; Tsujimura, Noriyuki; Otsuka, Kensuke; Yoshino, Tomoko; Mori, Tetsushi; Matsunaga, Tadashi; Nakasono, Satoshi

2012-04-01

Recently, humanized animals whereby a part of the animal is biologically engineered using human genes or cells have been utilized to overcome interspecific differences. Herein, we analyzed the detail of the differentiation states of various human leukocyte subpopulations in humanized mouse and evaluated comprehensively the similarity of the leukocyte lineage between humanized mice and humans. Humanized mice were established by transplanting human CD34(+) cord blood cells into irradiated severely immunodeficient NOD/Shi-scid/IL2Rγ(null) (NOG) mice, and the phenotypes of human cells contained in bone marrow, thymus, spleen and peripheral blood from the mice were analyzed at monthly intervals until 4 months after cell transplantation. The analysis revealed that transplanted human hematopoietic stem cells via the caudal vein homed and engrafted themselves successfully at the mouse bone marrow. Subsequently, the differentiated leukocytes migrated to the various tissues. Almost all of the leukocytes within the thymus were human cells. Furthermore, analysis of the differentiation states of human leukocytes in various tissues and organs indicated that it is highly likely that the human-like leukocyte lineage can be developed in mice. Copyright © 2011 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Expansion on stromal cells preserves the undifferentiated state of human hematopoietic stem cells despite compromised reconstitution ability.

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Magnusson, Mattias; Sierra, Maria I; Sasidharan, Rajkumar; Prashad, Sacha L; Romero, Melissa; Saarikoski, Pamela; Van Handel, Ben; Huang, Andy; Li, Xinmin; Mikkola, Hanna K A

2013-01-01

Lack of HLA-matched hematopoietic stem cells (HSC) limits the number of patients with life-threatening blood disorders that can be treated by HSC transplantation. So far, insufficient understanding of the regulatory mechanisms governing human HSC has precluded the development of effective protocols for culturing HSC for therapeutic use and molecular studies. We defined a culture system using OP9M2 mesenchymal stem cell (MSC) stroma that protects human hematopoietic stem/progenitor cells (HSPC) from differentiation and apoptosis. In addition, it facilitates a dramatic expansion of multipotent progenitors that retain the immunophenotype (CD34+CD38-CD90+) characteristic of human HSPC and proliferative potential over several weeks in culture. In contrast, transplantable HSC could be maintained, but not significantly expanded, during 2-week culture. Temporal analysis of the transcriptome of the ex vivo expanded CD34+CD38-CD90+ cells documented remarkable stability of most transcriptional regulators known to govern the undifferentiated HSC state. Nevertheless, it revealed dynamic fluctuations in transcriptional programs that associate with HSC behavior and may compromise HSC function, such as dysregulation of PBX1 regulated genetic networks. This culture system serves now as a platform for modeling human multilineage hematopoietic stem/progenitor cell hierarchy and studying the complex regulation of HSC identity and function required for successful ex vivo expansion of transplantable HSC.

Expansion on stromal cells preserves the undifferentiated state of human hematopoietic stem cells despite compromised reconstitution ability.

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Mattias Magnusson

Full Text Available Lack of HLA-matched hematopoietic stem cells (HSC limits the number of patients with life-threatening blood disorders that can be treated by HSC transplantation. So far, insufficient understanding of the regulatory mechanisms governing human HSC has precluded the development of effective protocols for culturing HSC for therapeutic use and molecular studies. We defined a culture system using OP9M2 mesenchymal stem cell (MSC stroma that protects human hematopoietic stem/progenitor cells (HSPC from differentiation and apoptosis. In addition, it facilitates a dramatic expansion of multipotent progenitors that retain the immunophenotype (CD34+CD38-CD90+ characteristic of human HSPC and proliferative potential over several weeks in culture. In contrast, transplantable HSC could be maintained, but not significantly expanded, during 2-week culture. Temporal analysis of the transcriptome of the ex vivo expanded CD34+CD38-CD90+ cells documented remarkable stability of most transcriptional regulators known to govern the undifferentiated HSC state. Nevertheless, it revealed dynamic fluctuations in transcriptional programs that associate with HSC behavior and may compromise HSC function, such as dysregulation of PBX1 regulated genetic networks. This culture system serves now as a platform for modeling human multilineage hematopoietic stem/progenitor cell hierarchy and studying the complex regulation of HSC identity and function required for successful ex vivo expansion of transplantable HSC.

Reconstruction of hematopoietic inductive microenvironment after transplantation of VCAM-1-modified human umbilical cord blood stromal cells.

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Yao Liu

Full Text Available The hematopoietic inductive microenvironment (HIM is where hematopoietic stem/progenitor cells grow and develop. Hematopoietic stromal cells were the key components of the HIM. In our previous study, we had successfully cultured and isolated human cord blood-derived stromal cells (HUCBSCs and demonstrated that they could secret hemopoietic growth factors such as GM-CSF, TPO, and SCF. However, it is still controversial whether HUCBSCs can be used for reconstruction of HIM. In this study, we first established a co-culture system of HUCBSCs and cord blood CD34(+ cells and then determined that using HUCBSCs as the adherent layer had significantly more newly formed colonies of each hematopoietic lineage than the control group, indicating that HUCBSCs had the ability to promote the proliferation of hematopoietic stem cells/progenitor cells. Furthermore, the number of colonies was significantly higher in vascular cell adhesion molecule-1 (VCAM-1-modified HUCBSCs, suggesting that the ability of HUCBSCs in promoting the proliferation of hematopoietic stem cells/progenitor cells was further enhanced after having been modified with VCAM-1. Next, HUCBSCs were infused into a radiation-damaged animal model, in which the recovery of hematopoiesis was observed. The results demonstrate that the transplanted HUCBSCs were "homed in" to bone marrow and played roles in promoting the recovery of irradiation-induced hematopoietic damage and repairing HIM. Compared with the control group, the HUCBSC group had significantly superior effectiveness in terms of the recovery time for hemogram and myelogram, CFU-F, CFU-GM, BFU-E, and CFU-Meg. Such differences were even more significant in VCAM-1-modified HUCBSCs group. We suggest that HUCBSCs are able to restore the functions of HIM and promote the recovery of radiation-induced hematopoietic damage. VCAM-1 plays an important role in supporting the repair of HIM damage.

A human monoclonal antibody drug and target discovery platform for B-cell chronic lymphocytic leukemia based on allogeneic hematopoietic stem cell transplantation and phage display

OpenAIRE

Baskar, Sivasubramanian; Suschak, Jessica M.; Samija, Ivan; Srinivasan, Ramaprasad; Childs, Richard W.; Pavletic, Steven Z.; Bishop, Michael R.; Rader, Christoph

2009-01-01

Allogeneic hematopoietic stem cell transplantation (alloHSCT) is the only potentially curative treatment available for patients with B-cell chronic lymphocytic leukemia (B-CLL). Here, we show that post-alloHSCT antibody repertoires can be mined for the discovery of fully human monoclonal antibodies to B-CLL cell-surface antigens. Sera collected from B-CLL patients at defined times after alloHSCT showed selective binding to primary B-CLL cells. Pre-alloHSCT sera, donor sera, and control sera w...

Recombinant adeno-associated virus mediates a high level of gene transfer but less efficient integration in the K562 human hematopoietic cell line.

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Malik, P; McQuiston, S A; Yu, X J; Pepper, K A; Krall, W J; Podsakoff, G M; Kurtzman, G J; Kohn, D B

1997-03-01

We tested the ability of a recombinant adeno-associated virus (rAAV) vector to express and integrate exogenous DNA into human hematopoietic cells in the absence of selection. We developed an rAAV vector, AAV-tNGFR, carrying a truncated rat nerve growth factor receptor (tNGFR) cDNA as a cell surface reporter under the control of the Moloney murine leukemia virus (MoMuLV) long terminal repeat. An analogous MoMuLV-based retroviral vector (L-tNGFR) was used in parallel, and gene transfer and expression in human hematopoietic cells were assessed by flow cytometry and DNA analyses. Following gene transfer into K562 cells with AAV-tNGFR at a multiplicity of infection (MOI) of 13 infectious units (IU), 26 to 38% of cells expressed tNGFR on the surface early after transduction, but the proportion of tNGFR expressing cells steadily declined to 3.0 to 3.5% over 1 month of culture. At an MOI of 130 IU, nearly all cells expressed tNGFR immediately posttransduction, but the proportion of cells expressing tNGFR declined to 62% over 2 months of culture. The decline in the proportion of AAV-tNGFR-expressing cells was associated with ongoing losses of vector genomes. In contrast, K562 cells transduced with the retroviral vector L-tNGFR expressed tNGFR in a constant fraction. Integration analyses on clones showed that integration occurred at different sites. Integration frequencies were estimated at about 49% at an MOI of 130 and 2% at an MOI of 1.3. Transduction of primary human CD34+ progenitor cells by AAV-tNGFR was less efficient than with K562 cells and showed a declining percentage of cells expressing tNGFR over 2 weeks of culture. Thus, purified rAAV caused very high gene transfer and expression in human hematopoietic cells early after transduction, which steadily declined during cell passage in the absence of selection. Although the efficiency of integration was low, overall integration was markedly improved at a high MOI. While prolonged episomal persistence may be adequate

Long-term leukocyte reconstitution in NSG mice transplanted with human cord blood hematopoietic stem and progenitor cells.

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Audigé, Annette; Rochat, Mary-Aude; Li, Duo; Ivic, Sandra; Fahrny, Audrey; Muller, Christina K S; Gers-Huber, Gustavo; Myburgh, Renier; Bredl, Simon; Schlaepfer, Erika; Scherrer, Alexandra U; Kuster, Stefan P; Speck, Roberto F

2017-05-30

Humanized mice (hu mice) are based on the transplantation of hematopoietic stem and progenitor cells into immunodeficient mice and have become important pre-clinical models for biomedical research. However, data about their hematopoiesis over time are scarce. We therefore characterized leukocyte reconstitution in NSG mice, which were sublethally irradiated and transplanted with human cord blood-derived CD34+ cells at newborn age, longitudinally in peripheral blood and, for more detailed analyses, cross-sectionally in peripheral blood, spleen and bone marrow at different time points. Human cell chimerism and absolute human cell count decreased between week 16 and 24 in the peripheral blood of hu mice, but were stable thereafter as assessed up to 32 weeks. Human cell chimerism in spleen and bone marrow was maintained over time. Notably, human cell chimerism in peripheral blood and spleen as well as bone marrow positively correlated with each other. Percentage of B cells decreased between week 16 and 24, whereas percentage of T cells increased; subsequently, they levelled off with T cells clearly predominating at week 32. Natural killer cells, monocytes and plasmacytoid dendritic cells (DCs) as well as CD1c + and CD141+ myeloid DCs were all present in hu mice. Proliferative responses of splenic T cells to stimulation were preserved over time. Importantly, the percentage of more primitive hematopoietic stem cells (HSCs) in bone marrow was maintained over time. Overall, leukocyte reconstitution was maintained up to 32 weeks post-transplantation in our hu NSG model, possibly explained by the maintenance of HSCs in the bone marrow. Notably, we observed great variation in multi-lineage hematopoietic reconstitution in hu mice that needs to be taken into account for the experimental design with hu mice.

PDGFRα and CD51 mark human nestin+ sphere-forming mesenchymal stem cells capable of hematopoietic progenitor cell expansion.

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Pinho, Sandra; Lacombe, Julie; Hanoun, Maher; Mizoguchi, Toshihide; Bruns, Ingmar; Kunisaki, Yuya; Frenette, Paul S

2013-07-01

The intermediate filament protein Nestin labels populations of stem/progenitor cells, including self-renewing mesenchymal stem cells (MSCs), a major constituent of the hematopoietic stem cell (HSC) niche. However, the intracellular location of Nestin prevents its use for prospective live cell isolation. Hence it is important to find surface markers specific for Nestin⁺ cells. In this study, we show that the expression of PDGFRα and CD51 among CD45⁻ Ter119⁻ CD31⁻ mouse bone marrow (BM) stromal cells characterizes a large fraction of Nestin⁺ cells, containing most fibroblastic CFUs, mesenspheres, and self-renewal capacity after transplantation. The PDGFRα⁺ CD51 ⁺subset of Nestin⁺ cells is also enriched in major HSC maintenance genes, supporting the notion that niche activity co-segregates with MSC activity. Furthermore, we show that PDGFRα⁺ CD51⁺ cells in the human fetal BM represent a small subset of CD146⁺ cells expressing Nestin and enriched for MSC and HSC niche activities. Importantly, cultured human PDGFRα⁺ CD51⁺ nonadherent mesenspheres can significantly expand multipotent hematopoietic progenitors able to engraft immunodeficient mice. These results thus indicate that the HSC niche is conserved between the murine and human species and suggest that highly purified nonadherent cultures of niche cells may represent a useful novel technology to culture human hematopoietic stem and progenitor cells.

Individual differences in the radiosensitivity of hematopoietic progenitor cells detected in steady-state human peripheral blood

International Nuclear Information System (INIS)

Oriya, Asami; Takahashi, Kenji; Kashiwakura, Ikuo; Inanami, Osamu; Kuwabara, Mikinori; Miura, Toshiaki; Abe, Yoshinao

2008-01-01

The aim of this study is to evaluate the individual differences in radiosensitivity of lineage-committed myeloid hematopoietic progenitors, colony-forming cells (CFC), detected in steady-state human peripheral blood (PB). Mononuclear cells were prepared from the buffy-coat of 30 individuals PB, and were assayed for CFC by semi-solid culture supplemented with cytokines. X irradiation was performed in the range of 0.5-4 Gy at a dose rate of about 80 cGy/min. The mean number of hematopoietic progenitor cells is 5866±3408 in 1 ml of buffy-coat, suggesting that the erythroid progenitor cells are the major population. The total CFC radiosensitivity parameter D 0 and n value are 1.18±0.24 and 1.89±0.98, respectively. Using a linear regression analysis, a statistically significant correlation is observed between the D 0 value and the surviving fraction at 4 Gy (r=0.611 p 0 parameter and the level of antioxidants, plasma uric acid, plasma bilirubin, and intracellular glutathione. The present study demonstrates that there are large individual differences in the radiosensitivity of hematopoietic progenitor cells as detected in steady-state human PB. These differences demonstrate almost no correlation with plasma or intracellular antioxidants. The prediction of individual differences in radiosensitivity of CFC can only be measured by 4 Gy irradiation. (author)

Site-Specific Gene Editing of Human Hematopoietic Stem Cells for X-Linked Hyper-IgM Syndrome

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Caroline Y. Kuo

2018-05-01

Full Text Available X-linked hyper-immunoglobulin M (hyper-IgM syndrome (XHIM is a primary immunodeficiency due to mutations in CD40 ligand that affect immunoglobulin class-switch recombination and somatic hypermutation. The disease is amenable to gene therapy using retroviral vectors, but dysregulated gene expression results in abnormal lymphoproliferation in mouse models, highlighting the need for alternative strategies. Here, we demonstrate the ability of both the transcription activator-like effector nuclease (TALEN and clustered regularly interspaced short palindromic repeats-associated protein 9 (CRISPR/Cas9 platforms to efficiently drive integration of a normal copy of the CD40L cDNA delivered by Adeno-Associated Virus. Site-specific insertion of the donor sequence downstream of the endogenous CD40L promoter maintained physiologic expression of CD40L while overriding all reported downstream mutations. High levels of gene modification were achieved in primary human hematopoietic stem cells (HSCs, as well as in cell lines and XHIM-patient-derived T cells. Notably, gene-corrected HSCs engrafted in immunodeficient mice at clinically relevant frequencies. These studies provide the foundation for a permanent curative therapy in XHIM.

Formation and hematopoietic differentiation of human embryoid bodies by suspension and hanging drop cultures.

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Cerdan, Chantal; Hong, Seok Ho; Bhatia, Mickie

2007-10-01

The in vitro aggregation of human embryonic stem cells (hESCs) into clusters termed embryoid bodies (EBs) allows for the spontaneous differentiation of cells representing endoderm, mesoderm, and ectoderm lineages. This stochastic process results however, in the generation of low numbers of differentiated cells, and can be enhanced to some extent by the addition of exogenous growth factors or overexpression of regulatory genes. In the authors' laboratory, the use of hematopoietic cytokines in combination with the mesoderm inducer bone morphogenetic protein-4 (BMP-4) was able to generate up to 90% of CD45(+) hematopoietic cells with colony-forming unit (CFU) activity. This unit describes two protocols that have been successfully applied in the authors' laboratory for the generation of EBs in (1) suspension and (2) hanging drop (HD) cultures from enzymatically digested clumps of undifferentiated hESC colonies.

PLAG1 and USF2 Co-regulate Expression of Musashi-2 in Human Hematopoietic Stem and Progenitor Cells

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Muluken S. Belew

2018-04-01

Full Text Available Summary: MSI2, which is expressed predominantly in hematopoietic stem and progenitor cells (HSPCs, enforces HSPC expansion when overexpressed and is upregulated in myeloid leukemias, indicating its regulated transcription is critical to balanced self-renewal and leukemia restraint. Despite this, little is understood of the factors that enforce appropriate physiological levels of MSI2 in the blood system. Here, we define a promoter region that reports on endogenous expression of MSI2 and identify USF2 and PLAG1 as transcription factors whose promoter binding drives reporter activity. We show that these factors co-regulate, and are required for, efficient transactivation of endogenous MSI2. Coincident overexpression of USF2 and PLAG1 in primitive cord blood cells enhanced MSI2 transcription and yielded cellular phenotypes, including expansion of CD34+ cells in vitro, consistent with that achieved by direct MSI2 overexpression. Global chromatin immunoprecipitation sequencing analyses confirm a preferential co-binding of PLAG1 and USF2 at the promoter of MSI2, as well as regulatory regions corresponding to genes with roles in HSPC homeostasis. PLAG1 and USF2 cooperation is thus an important contributor to stem cell-specific expression of MSI2 and HSPC-specific transcriptional circuitry. : MSI2 is an essential human hematopoietic stem and progenitor cell (HSPC regulator, but knowledge of the mechanisms ensuring its appropriate expression in this context are lacking. Here, Hope and colleagues map the MSI2 promoter functional in hematopoietic cells and identify USF2 and PLAG1 as essential, cooperative enforcers of endogenous MSI2 expression and stemness traits in human HSPCs. Keywords: human hematopoietic stem cells, self-renewal, promoter, transcriptional regulation, transcription factors, Musashi-2, genome-wide DNA binding site mapping, PLAG1, USF2

Dissociation of Survival, Proliferation, and State Control in Human Hematopoietic Stem Cells.

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Knapp, David J H F; Hammond, Colin A; Miller, Paul H; Rabu, Gabrielle M; Beer, Philip A; Ricicova, Marketa; Lecault, Véronique; Da Costa, Daniel; VanInsberghe, Michael; Cheung, Alice M; Pellacani, Davide; Piret, James; Hansen, Carl; Eaves, Connie J

2017-01-10

The role of growth factors (GFs) in controlling the biology of human hematopoietic stem cells (HSCs) remains limited by a lack of information concerning the individual and combined effects of GFs directly on the survival, Mitogenesis, and regenerative activity of highly purified human HSCs. We show that the initial input HSC activity of such a purified starting population of human cord blood cells can be fully maintained over a 21-day period in serum-free medium containing five GFs alone. HSC survival was partially supported by any one of these GFs, but none were essential, and different combinations of GFs variably stimulated HSC proliferation. However, serial transplantability was not detectably compromised by many conditions that reduced human HSC proliferation and/or survival. These results demonstrate the dissociated control of these three human HSC bio-responses, and set the stage for future improvements in strategies to modify and expand human HSCs ex vivo. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

Correction of glucocerebrosidase deficiency after retroviral-mediated gene transfer into hematopoietic progenitor cells from patients with Gaucher disease

International Nuclear Information System (INIS)

Fink, J.K.; Correll, P.H.; Perry, L.K.; Brady, R.O.; Karlsson, S.

1990-01-01

Retroviral gene transfer has been used successfully to correct the glucocerebrosidase (GCase) deficiency in primary hematopoietic cells from patients with Gaucher disease. For this model of somatic gene therapy, the authors developed a high-titer, amphotropic retroviral vector designated NTG in which the human GCase gene was driven by the mutant polyoma virus enhancer/herpesvirus thymidine kinase gene (tk) promoter (Py + /Htk). NTG normalized GCase activity in transduced Gaucher fibroblasts and efficiently infected human monocytic and erythroleukemic cell lines. RNA blot-hybridization (Northern blot) analysis of these hemaptopoietic cell lines showed unexpectedly high-level expression from the Moloney murine leukemia virus long terminal repeat (Mo-MLV LTR) and levels of Py + /Htk enhancer/promoter-initiated human GCase RNA that approximated endogenous GCase RNA levels. Furthermore, NTG efficiently infected human hematopoietic progenitor cells. Detection of the provirus in approximately one-third of NTG-infected progenitor colonies that had not been selected in G418-containing medium indicates that relative resistance to G418 underestimated the actual gene transfer efficiency. Northern blot analysis of NTG-infected, progenitor-derived cells showed expression from both the Mo-MLV LTR and the Py + /Htk enhancer/promoter. NTG-transduced hematopoietic progenitor cells from patients with Gaucher disease generated progeny in which GCase activity has been normalized

Correction of glucocerebrosidase deficiency after retroviral-mediated gene transfer into hematopoietic progenitor cells from patients with Gaucher disease

Energy Technology Data Exchange (ETDEWEB)

Fink, J.K.; Correll, P.H.; Perry, L.K.; Brady, R.O.; Karlsson, S. (National Institutes of Health, Bethesda, MD (USA))

1990-03-01

Retroviral gene transfer has been used successfully to correct the glucocerebrosidase (GCase) deficiency in primary hematopoietic cells from patients with Gaucher disease. For this model of somatic gene therapy, the authors developed a high-titer, amphotropic retroviral vector designated NTG in which the human GCase gene was driven by the mutant polyoma virus enhancer/herpesvirus thymidine kinase gene (tk) promoter (Py{sup +}/Htk). NTG normalized GCase activity in transduced Gaucher fibroblasts and efficiently infected human monocytic and erythroleukemic cell lines. RNA blot-hybridization (Northern blot) analysis of these hemaptopoietic cell lines showed unexpectedly high-level expression from the Moloney murine leukemia virus long terminal repeat (Mo-MLV LTR) and levels of Py{sup +}/Htk enhancer/promoter-initiated human GCase RNA that approximated endogenous GCase RNA levels. Furthermore, NTG efficiently infected human hematopoietic progenitor cells. Detection of the provirus in approximately one-third of NTG-infected progenitor colonies that had not been selected in G418-containing medium indicates that relative resistance to G418 underestimated the actual gene transfer efficiency. Northern blot analysis of NTG-infected, progenitor-derived cells showed expression from both the Mo-MLV LTR and the Py{sup +}/Htk enhancer/promoter. NTG-transduced hematopoietic progenitor cells from patients with Gaucher disease generated progeny in which GCase activity has been normalized.

A stable murine-based RD114 retroviral packaging line efficiently transduces human hematopoietic cells.

Science.gov (United States)

Ward, Maureen; Sattler, Rose; Grossman, I Robert; Bell, Anthony J; Skerrett, Donna; Baxi, Laxmi; Bank, Arthur

2003-11-01

Several barriers exist to high-efficiency transfer of therapeutic genes into human hematopoietic stem cells (HSCs) using complex oncoretroviral vectors. Human clinical trials to date have used Moloney leukemia virus-based amphotropic and gibbon ape leukemia virus-based envelopes in stable retroviral packaging lines. However, retroviruses pseudotyped with these envelopes have low titers due to the inability to concentrate viral supernatants efficiently by centrifugation without damaging the virus and low transduction efficiencies because of low-level expression of viral target receptors on human HSC. The RD114 envelope from the feline endogenous virus has been shown to transduce human CD34+ cells using transient packaging systems and to be concentrated to high titers by centrifugation. Stable packaging systems have potential advantages over transient systems because greater and more reproducible viral productions can be attained. We have, therefore, constructed and tested a stable RD114-expressing packaging line capable of high-level transduction of human CD34+ cells. Viral particles from this cell line were concentrated up to 100-fold (up to 10(7) viral particles/ml) by ultracentrifugation. Human hematopoietic progenitors from cord blood and sickle cell CD34+ cells were efficiently transduced with a Neo(R)-containing vector after a single exposure to concentrated RD114-pseudotyped virus produced from this cell line. Up to 78% of progenitors from transduced cord blood CD34+ cells and 51% of progenitors from sickle cell CD34+ cells expressed the NeoR gene. We also show transfer of a human beta-globin gene into progenitor cells from CD34+ cells from sickle cell patients with this new RD114 stable packaging system. The results indicate that this packaging line may eventually be useful in human clinical trials of globin gene therapy.

Knockdown of HSPA9 induces TP53-dependent apoptosis in human hematopoietic progenitor cells.

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Tuoen Liu

Full Text Available Myelodysplastic syndromes (MDS are the most common adult myeloid blood cancers in the US. Patients have increased apoptosis in their bone marrow cells leading to low peripheral blood counts. The full complement of gene mutations that contribute to increased apoptosis in MDS remains unknown. Up to 25% of MDS patients harbor and acquired interstitial deletion on the long arm of chromosome 5 [del(5q], creating haploinsufficiency for a large set of genes including HSPA9. Knockdown of HSPA9 in primary human CD34+ hematopoietic progenitor cells significantly inhibits growth and increases apoptosis. We show here that HSPA9 knockdown is associated with increased TP53 expression and activity, resulting in increased expression of target genes BAX and p21. HSPA9 protein interacts with TP53 in CD34+ cells and knockdown of HSPA9 increases nuclear TP53 levels, providing a possible mechanism for regulation of TP53 by HSPA9 haploinsufficiency in hematopoietic cells. Concurrent knockdown of TP53 and HSPA9 rescued the increased apoptosis observed in CD34+ cells following knockdown of HSPA9. Reduction of HSPA9 below 50% results in severe inhibition of cell growth, suggesting that del(5q cells may be preferentially sensitive to further reductions of HSPA9 below 50%, thus providing a genetic vulnerability to del(5q cells. Treatment of bone marrow cells with MKT-077, an HSPA9 inhibitor, induced apoptosis in a higher percentage of cells from MDS patients with del(5q compared to non-del(5q MDS patients and normal donor cells. Collectively, these findings indicate that reduced levels of HSPA9 may contribute to TP53 activation and increased apoptosis observed in del(5q-associated MDS.

The Polycomb Group Protein L3MBTL1 Represses a SMAD5-Mediated Hematopoietic Transcriptional Program in Human Pluripotent Stem Cells

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Fabiana Perna

2015-04-01

Full Text Available Epigenetic regulation of key transcriptional programs is a critical mechanism that controls hematopoietic development, and, thus, aberrant expression patterns or mutations in epigenetic regulators occur frequently in hematologic malignancies. We demonstrate that the Polycomb protein L3MBTL1, which is monoallelically deleted in 20q- myeloid malignancies, represses the ability of stem cells to drive hematopoietic-specific transcriptional programs by regulating the expression of SMAD5 and impairing its recruitment to target regulatory regions. Indeed, knockdown of L3MBTL1 promotes the development of hematopoiesis and impairs neural cell fate in human pluripotent stem cells. We also found a role for L3MBTL1 in regulating SMAD5 target gene expression in mature hematopoietic cell populations, thereby affecting erythroid differentiation. Taken together, we have identified epigenetic priming of hematopoietic-specific transcriptional networks, which may assist in the development of therapeutic approaches for patients with anemia.

A curated transcriptome dataset collection to investigate the functional programming of human hematopoietic cells in early life.

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Rahman, Mahbuba; Boughorbel, Sabri; Presnell, Scott; Quinn, Charlie; Cugno, Chiara; Chaussabel, Damien; Marr, Nico

2016-01-01

Compendia of large-scale datasets made available in public repositories provide an opportunity to identify and fill gaps in biomedical knowledge. But first, these data need to be made readily accessible to research investigators for interpretation. Here we make available a collection of transcriptome datasets to investigate the functional programming of human hematopoietic cells in early life. Thirty two datasets were retrieved from the NCBI Gene Expression Omnibus (GEO) and loaded in a custom web application called the Gene Expression Browser (GXB), which was designed for interactive query and visualization of integrated large-scale data. Quality control checks were performed. Multiple sample groupings and gene rank lists were created allowing users to reveal age-related differences in transcriptome profiles, changes in the gene expression of neonatal hematopoietic cells to a variety of immune stimulators and modulators, as well as during cell differentiation. Available demographic, clinical, and cell phenotypic information can be overlaid with the gene expression data and used to sort samples. Web links to customized graphical views can be generated and subsequently inserted in manuscripts to report novel findings. GXB also enables browsing of a single gene across projects, thereby providing new perspectives on age- and developmental stage-specific expression of a given gene across the human hematopoietic system. This dataset collection is available at: http://developmentalimmunology.gxbsidra.org/dm3/geneBrowser/list.

Nonirradiated NOD,B6.SCID Il2rγ−/− KitW41/W41 (NBSGW Mice Support Multilineage Engraftment of Human Hematopoietic Cells

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Brian E. McIntosh

2015-02-01

Full Text Available In this study, we demonstrate a newly derived mouse model that supports engraftment of human hematopoietic stem cells (HSCs in the absence of irradiation. We cross the NOD.Cg-PrkdcscidIl2rgtm1Wjl/SzJ (NSG strain with the C57BL/6J-KitW-41J/J (C57BL/6.KitW41 strain and engraft, without irradiation, the resulting NBSGW strain with human cord blood CD34+ cells. At 12-weeks postengraftment in NBSGW mice, we observe human cell chimerism in marrow (97% ± 0.4%, peripheral blood (61% ± 2%, and spleen (94% ± 2% at levels observed with irradiation in NSG mice. We also detected a significant number of glycophorin-A-positive expressing cells in the developing NBSGW marrow. Further, the observed levels of human hematopoietic chimerism mimic those reported for both irradiated NSG and NSG-transgenic strains. This mouse model permits HSC engraftment while avoiding the complicating hematopoietic, gastrointestinal, and neurological side effects associated with irradiation and allows investigators without access to radiation to pursue engraftment studies with human HSCs.

Identification of the homing molecules that escort pluripotent stem cells-derived hematopoietic stem cells to their niches and human activated T-cells to inflammatory sites.

KAUST Repository

Ali, Amal

2017-12-01

Hematopoietic cells exploit the multistep paradigm of cell migration to ultimately enable them to perform their function. This process is dictated by the ability of adhesion molecules on the circulating hematopoietic cells to find their counter-receptors on endothelial cells. Of those molecules, the selectin family and their respective ligands induce the initial transient interactions between circulating cells and the opposing endothelium. In this thesis, I focused on studying E-selectin mediated cellular migration in two hematopoietic cell types, namely human hematopoietic stem and progenitor cells (HSPCs) and human T-lymphocytes. HSPCs derived from pluripotent sources theoretically offers a novel, unlimited source for hematopoietic stem cell transplantation therapy. In vitro pluripotent stem cell derived- hematopoietic stem/progenitor cells (ES/iPS-HSPCs) behave much like somatic HSPCs in that they exhibit clonal expansion and multilineage hematopoietic capacity. However, unlike somatic sources, ES/iPS-HSPCs do not give rise to effective hematopoietic repopulation, which may be due to insufficient HSPCs homing to the bone marrow. HSPCs exploit E- and P-selectin to home and engraft into bone marrow niches. Thus, one of my objectives in this thesis was to study the expression of E-selectin ligands associated with ES/iPS-HSPCs. I showed that ES/iPS-HSPCs lack functional E-selectin ligand(s). In an effort to enhance the interaction between Eselectin and ES/iPS-HSPCs, we decorated the cell surface with sialyl-Lewis x (sLex) using the ex-vivo glycan engineering technology. However, this decoration did not improve the engraftment capacity of ES/iPS-HSPCs, in vivo. Induction of E-selectin expression during inflammation is key to recruitment of immune cells and therefore I also focused on analyzing the expression of E-selectin ligands on activated human T-cells. I identified several novel glycoproteins that may function as E-selectin ligands. Specifically, I compared the

In vitro and in vivo assessment of direct effects of simulated solar and galactic cosmic radiation on human hematopoietic stem/progenitor cells.

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Rodman, C; Almeida-Porada, G; George, S K; Moon, J; Soker, S; Pardee, T; Beaty, M; Guida, P; Sajuthi, S P; Langefeld, C D; Walker, S J; Wilson, P F; Porada, C D

2017-06-01

Future deep space missions to Mars and near-Earth asteroids will expose astronauts to chronic solar energetic particles (SEP) and galactic cosmic ray (GCR) radiation, and likely one or more solar particle events (SPEs). Given the inherent radiosensitivity of hematopoietic cells and short latency period of leukemias, space radiation-induced hematopoietic damage poses a particular threat to astronauts on extended missions. We show that exposing human hematopoietic stem/progenitor cells (HSC) to extended mission-relevant doses of accelerated high-energy protons and iron ions leads to the following: (1) introduces mutations that are frequently located within genes involved in hematopoiesis and are distinct from those induced by γ-radiation; (2) markedly reduces in vitro colony formation; (3) markedly alters engraftment and lineage commitment in vivo; and (4) leads to the development, in vivo, of what appears to be T-ALL. Sequential exposure to protons and iron ions (as typically occurs in deep space) proved far more deleterious to HSC genome integrity and function than either particle species alone. Our results represent a critical step for more accurately estimating risks to the human hematopoietic system from space radiation, identifying and better defining molecular mechanisms by which space radiation impairs hematopoiesis and induces leukemogenesis, as well as for developing appropriately targeted countermeasures.

CRISPR/Cas9 system and its applications in human hematopoietic cells.

Science.gov (United States)

Hu, Xiaotang

2016-11-01

Since 2012, the CRISPR-Cas9 system has been quickly and successfully tested in a broad range of organisms and cells including hematopoietic cells. The application of CRISPR-Cas9 in human hematopoietic cells mainly involves the genes responsible for HIV infection, β-thalassemia and sickle cell disease (SCD). The successful disruption of CCR5 and CXCR4 genes in T cells by CRISPR-Cas9 promotes the prospect of the technology in the functional cure of HIV. More recently, eliminating CCR5 and CXCR4 in induced pluripotent stem cells (iPSCs) derived from patients and targeting the HIV genome have been successfully carried out in several laboratories. The outcome from these approaches bring us closer to the goal of eradicating HIV infection. For hemoglobinopathies the ability to produce iPSC-derived from patients with the correction of hemoglobin (HBB) mutations by CRISPR-Cas9 has been tested in a number of laboratories. These corrected iPSCs also show the potential to differentiate into mature erythrocytes expressing high-level and normal HBB. In light of the initial success of CRESPR-Cas9 in target mutated gene(s) in the iPSCs, a combination of genomic editing and autogenetic stem cell transplantation would be the best strategy for root treatment of the diseases, which could replace traditional allogeneic stem cell transplantation. Copyright © 2016 Elsevier Inc. All rights reserved.

Novel anti-c-Mpl monoclonal antibodies identified multiple differentially glycosylated human c-Mpl proteins in megakaryocytic cells but not in human solid tumors.

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Zhan, Jinghui; Felder, Barbara; Ellison, Aaron R; Winters, Aaron; Salimi-Moosavi, Hossein; Scully, Sheila; Turk, James R; Wei, Ping

2013-06-01

Thrombopoietin and its cognate receptor, c-Mpl, are the primary molecular regulators of megakaryocytopoiesis and platelet production. To date the pattern of c-Mpl expression in human solid tumors and the distribution and biochemical properties of c-Mpl proteins in hematopoietic tissues are largely unknown. We have recently developed highly specific mouse monoclonal antibodies (MAb) against human c-Mpl. In this study we used these antibodies to demonstrate the presence of full-length and truncated human c-Mpl proteins in various megakaryocytic cell types, and their absence in over 100 solid tumor cell lines and in the 12 most common primary human tumor types. Quantitative assays showed a cell context-dependent distribution of full-length and truncated c-Mpl proteins. All forms of human c-Mpl protein were found to be modified with extensive N-linked glycosylation but different degrees of sialylation and O-linked glycosylation. Of note, different variants of full-length c-Mpl protein exhibiting differential glycosylation were expressed in erythromegakaryocytic leukemic cell lines and in platelets from healthy human donors. This work provides a comprehensive analysis of human c-Mpl mRNA and protein expression on normal and malignant hematopoietic and non-hematopoietic cells and demonstrates the multiple applications of several novel anti-c-Mpl antibodies.

Growth regulation on human acute myeloid leukemia effects of five recombinant hematopoietic factors in a serum-free culture system

NARCIS (Netherlands)

Delwel, E.; Salem, M.; Pellens, C.; Dorssers, L.; Wagemaker, G.; Clark, S.; Loewenberg, B

1988-01-01

The response of human acute myeloid leukemia (AML) cells to the distinct hematopoietic growth factors (HGFs), ie, recombinant interleukin-3 (IL-3), granulocyte-macrophage-CSF (GM-CSF), granulocyte-CSF (G-CSF), macrophage-CSF (M-CSF), and erythropoietin (Epo) was investigated under well-defined

Differentiation of embryonic stem cells towards hematopoietic cells: progress and pitfalls.

Science.gov (United States)

Tian, Xinghui; Kaufman, Dan S

2008-07-01

Hematopoietic development from embryonic stem cells has been one of the most productive areas of stem cell biology. Recent studies have progressed from work with mouse to human embryonic stem cells. Strategies to produce defined blood cell populations can be used to better understand normal and abnormal hematopoiesis, as well as potentially improve the generation of hematopoietic cells with therapeutic potential. Molecular profiling, phenotypic and functional analyses have all been utilized to demonstrate that hematopoietic cells derived from embryonic stem cells most closely represent a stage of hematopoiesis that occurs at embryonic/fetal developmental stages. Generation of hematopoietic stem/progenitor cells comparable to hematopoietic stem cells found in the adult sources, such as bone marrow and cord blood, still remains challenging. However, genetic manipulation of intrinsic factors during hematopoietic differentiation has proven a suitable approach to induce adult definitive hematopoiesis from embryonic stem cells. Concrete evidence has shown that embryonic stem cells provide a powerful approach to study the early stage of hematopoiesis. Multiple hematopoietic lineages can be generated from embryonic stem cells, although most of the evidence suggests that hematopoietic development from embryonic stem cells mimics an embryonic/fetal stage of hematopoiesis.

A human monoclonal antibody drug and target discovery platform for B-cell chronic lymphocytic leukemia based on allogeneic hematopoietic stem cell transplantation and phage display.

Science.gov (United States)

Baskar, Sivasubramanian; Suschak, Jessica M; Samija, Ivan; Srinivasan, Ramaprasad; Childs, Richard W; Pavletic, Steven Z; Bishop, Michael R; Rader, Christoph

2009-11-12

Allogeneic hematopoietic stem cell transplantation (alloHSCT) is the only potentially curative treatment available for patients with B-cell chronic lymphocytic leukemia (B-CLL). Here, we show that post-alloHSCT antibody repertoires can be mined for the discovery of fully human monoclonal antibodies to B-CLL cell-surface antigens. Sera collected from B-CLL patients at defined times after alloHSCT showed selective binding to primary B-CLL cells. Pre-alloHSCT sera, donor sera, and control sera were negative. To identify post-alloHSCT serum antibodies and subsequently B-CLL cell-surface antigens they recognize, we generated a human antibody-binding fragment (Fab) library from post-alloHSCT peripheral blood mononuclear cells and selected it on primary B-CLL cells by phage display. A panel of Fab with B-CLL cell-surface reactivity was strongly enriched. Selection was dominated by highly homologous Fab predicted to bind the same antigen. One Fab was converted to immunoglobulin G1 and analyzed for reactivity with peripheral blood mononuclear cells from B-CLL patients and healthy volunteers. Cell-surface antigen expression was restricted to primary B cells and up-regulated in primary B-CLL cells. Mining post-alloHSCT antibody repertoires offers a novel route to discover fully human monoclonal antibodies and identify antigens of potential therapeutic relevance to B-CLL and possibly other cancers. Trials described herein were registered at www.clinicaltrials.gov as nos. NCT00055744 and NCT00003838.

The New Self-Inactivating Lentiviral Vector for Thalassemia Gene Therapy Combining Two HPFH Activating Elements Corrects Human Thalassemic Hematopoietic Stem Cells

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Papanikolaou, Eleni; Georgomanoli, Maria; Stamateris, Evangelos; Panetsos, Fottes; Karagiorga, Markisia; Tsaftaridis, Panagiotis; Graphakos, Stelios

2012-01-01

Abstract To address how low titer, variable expression, and gene silencing affect gene therapy vectors for hemoglobinopathies, in a previous study we successfully used the HPFH (hereditary persistence of fetal hemoglobin)-2 enhancer in a series of oncoretroviral vectors. On the basis of these data, we generated a novel insulated self-inactivating (SIN) lentiviral vector, termed GGHI, carrying the Aγ-globin gene with the −117 HPFH point mutation and the HPFH-2 enhancer and exhibiting a pancellular pattern of Aγ-globin gene expression in MEL-585 clones. To assess the eventual clinical feasibility of this vector, GGHI was tested on CD34+ hematopoietic stem cells from nonmobilized peripheral blood or bone marrow from 20 patients with β-thalassemia. Our results show that GGHI increased the production of γ-globin by 32.9% as measured by high-performance liquid chromatography (p=0.001), with a mean vector copy number per cell of 1.1 and a mean transduction efficiency of 40.3%. Transduced populations also exhibited a lower rate of apoptosis and resulted in improvement of erythropoiesis with a higher percentage of orthochromatic erythroblasts. This is the first report of a locus control region (LCR)-free SIN insulated lentiviral vector that can be used to efficiently produce the anticipated therapeutic levels of γ-globin protein in the erythroid progeny of primary human thalassemic hematopoietic stem cells in vitro. PMID:21875313

Autophagy as an ultrastructural marker of heavy metal toxicity in human cord blood hematopoietic stem cells

International Nuclear Information System (INIS)

Di Gioacchino, Mario; Petrarca, Claudia; Perrone, Angela; Farina, Massimo; Sabbioni, Enrico; Hartung, Thomas; Martino, Simone; Esposito, Diana L.; Lotti, Lavinia Vittoria; Mariani-Costantini, Renato

2008-01-01

Stem cells are a key target of environmental toxicants, but little is known about their toxicological responses. We aimed at developing an in-vitro model based on adult human stem cells to identify biomarkers of heavy metal exposure. To this end we investigated the responses of human CD34+ hematopoietic progenitor cells to hexavalent chromium (Cr[VI]) and cadmium (Cd). Parallel cultures of CD34+ cells isolated from umbilical cord blood were exposed for 48 h to 0.1 μM and 10 μM Cr(VI) or Cd. Cultures treated with 10 μM Cr(VI) or Cd showed marked cell loss. Ultrastructural analysis of surviving cells revealed prominent autophagosomes/autophagolysosomes, which is diagnostic of autophagy, associated with mitochondrial damage and replication, dilatation of the rough endoplasmic reticulum and Golgi complex, cytoplasmic lipid droplets and chromatin condensation. Treated cells did not show the morphologic hallmarks of apoptosis. Treatment with 0.1 μM Cr(VI) or Cd did not result in cell loss, but at the ultrastructural level cells showed dilated endoplasmic reticulum and evidence of mitochondrial damage. We conclude that autophagy is implicated in the response of human hematopoietic stem cells to toxic concentrations of Cr(VI) and Cd. Autophagy, which mediates cell survival and death under stress, deserves further evaluation to be established as biomarker of metal exposure

Autophagy as an ultrastructural marker of heavy metal toxicity in human cord blood hematopoietic stem cells

Energy Technology Data Exchange (ETDEWEB)

Di Gioacchino, Mario [Aging Research Center, ' G. d' Annunzio' University Foundation, Via Colle dell' Ara, 66100 Chieti (Italy); Medicine and Science of Ageing University of Chieti-Pescara, Via dei Vestini 1, 66100 Chieti (Italy)], E-mail: m.digioacchino@unich.it; Petrarca, Claudia; Perrone, Angela [Aging Research Center, ' G. d' Annunzio' University Foundation, Via Colle dell' Ara, 66100 Chieti (Italy); Medicine and Science of Ageing University of Chieti-Pescara, Via dei Vestini 1, 66100 Chieti (Italy); Farina, Massimo; Sabbioni, Enrico; Hartung, Thomas [Oncology and Neurosciences University of Chieti-Pescara, Via dei Vestini 1, 66100 Chieti (Italy); Martino, Simone [Department of Experimental Medicine, University La Sapienza, Viale Regina Elena 324, 00161 Rome (Italy); Esposito, Diana L. [Aging Research Center, ' G. d' Annunzio' University Foundation, Via Colle dell' Ara, 66100 Chieti (Italy); Oncology and Neurosciences University of Chieti-Pescara, Via dei Vestini 1, 66100 Chieti (Italy); Lotti, Lavinia Vittoria [Department of Experimental Medicine, University La Sapienza, Viale Regina Elena 324, 00161 Rome (Italy); Mariani-Costantini, Renato [Aging Research Center, ' G. d' Annunzio' University Foundation, Via Colle dell' Ara, 66100 Chieti (Italy); Oncology and Neurosciences University of Chieti-Pescara, Via dei Vestini 1, 66100 Chieti (Italy)

2008-03-15

Stem cells are a key target of environmental toxicants, but little is known about their toxicological responses. We aimed at developing an in-vitro model based on adult human stem cells to identify biomarkers of heavy metal exposure. To this end we investigated the responses of human CD34+ hematopoietic progenitor cells to hexavalent chromium (Cr[VI]) and cadmium (Cd). Parallel cultures of CD34+ cells isolated from umbilical cord blood were exposed for 48 h to 0.1 {mu}M and 10 {mu}M Cr(VI) or Cd. Cultures treated with 10 {mu}M Cr(VI) or Cd showed marked cell loss. Ultrastructural analysis of surviving cells revealed prominent autophagosomes/autophagolysosomes, which is diagnostic of autophagy, associated with mitochondrial damage and replication, dilatation of the rough endoplasmic reticulum and Golgi complex, cytoplasmic lipid droplets and chromatin condensation. Treated cells did not show the morphologic hallmarks of apoptosis. Treatment with 0.1 {mu}M Cr(VI) or Cd did not result in cell loss, but at the ultrastructural level cells showed dilated endoplasmic reticulum and evidence of mitochondrial damage. We conclude that autophagy is implicated in the response of human hematopoietic stem cells to toxic concentrations of Cr(VI) and Cd. Autophagy, which mediates cell survival and death under stress, deserves further evaluation to be established as biomarker of metal exposure.

Transgene expression, but not gene delivery, is improved by adhesion-assisted lipofection of hematopoietic cells.

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Keller, H; Yunxu, C; Marit, G; Pla, M; Reiffers, J; Thèze, J; Froussard, P

1999-05-01

In contrast to adherent cells, cells growing in suspension and particularly hematopoietic cells, are notoriously difficult to transfect in vitro using nonviral approaches. In the present study, the effect of cell adhesion on gene transfer efficacy was investigated by allowing hematopoietic cells to bind to an adherent cell monolayer (ACM) before being subjected to cationic liposome-mediated DNA transfer. Human CD34 and T CD4 cell lines were cultivated on an ACM constituted of murine fibroblast NIH3T3 cells and transfected with a plasmid carrying the beta-galactosidase gene. X-gal staining showed that up to 27% of the cells expressed the transgene. In contrast, less than 0.1% of these cells were positively transfected in suspension. This adhesion-assisted lipofection (AAL) procedure was also successfully tested on blood lymphocytes, since it resulted in up to 30% of transfected human primary T lymphocytes. Flow cytometry analysis performed on T lymphocyte subsets revealed that 8 and 9%, respectively, of CD4 and CD8 cells could be transfected with a plasmid carrying the green fluorescent protein gene. Other adherent cells, such as MS5 murine stromal cells or HeLa epithelial cells, were also a compatible matrix for AAL. Moreover, the pCMV beta plasmid was present in similar amounts in the nuclei of TF1 cells transfected in suspension or with the AAL procedure. These data raise the possibility that cell matrix/hematopoietic cell interactions might govern expression of the transgene in hematopoietic cells growing usually in suspension, but not endocytosis of liposome/DNA particles and plasmid migration ot the cell nucleus.

Aging impairs long-term hematopoietic regeneration after autologous stem cell transplantation

NARCIS (Netherlands)

Woolthuis, Carolien M; Mariani, Niccoló; Verkaik-Schakel, Rikst Nynke; Brouwers-Vos, Annet Z.; Schuringa, Jan Jacob; Vellenga, Edo; de Wolf, Joost T M; Huls, Gerwin

Most of our knowledge of the effects of aging on the hematopoietic system comes from studies in animal models. In this study, to explore potential effects of aging on human hematopoietic stem and progenitor cells (HSPCs), we evaluated CD34(+) cells derived from young (<35 years) and old (>60 years)

Lipofectamine and related cationic lipids strongly improve adenoviral infection efficiency of primitive human hematopoietic cells.

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Byk, T; Haddada, H; Vainchenker, W; Louache, F

1998-11-20

Adenoviral vectors have the potential to infect a large number of cell types including quiescent cells. Their use in hematopoietic cells is limited by the episomal form of their DNA, leading to transgene loss in the progeny cells. However, the use of this vector may be interesting for short-term in vitro modifications of primitive human hematopoietic cells. Therefore, we have investigated the ability of adenovirus to transduce cord blood CD34+ cells. Several promoters were tested using the lacZ reporter gene. The PGK and CMV promoters induced transgene expression in 18-25% of the cells, whereas the HTLV-I and especially the RSV promoter were almost inactive. To improve infection efficiency, adenovirus was complexed with cationic lipids. Lipofectamine, Cellfectin, and RPR120535b, but not Lipofectin, Lipofectace, or DOTAP, markedly improved transgene expression in CD34+ cells (from 19 to 35%). Lipofectamine strongly enhanced infection efficiency of the poorly infectable primitive CD34+CD38low cells (from 11 to 28%) whereas the more mature CD34+CD38+ cells were only slightly affected (from 24 to 31%). Lipofectamine tripled the infection of CFU-GMs and LTC-ICs derived from the CD34+CD38low cell fraction (from 4 to 12% and from 5 to 16%, respectively) and doubled that of BFU-Es (from 13 to 26%). We conclude that cationic lipids can markedly increase the efficiency of adenovirus-mediated gene transfer into primitive hematopoietic cells.

Integration of adeno-associated virus vectors in CD34+ human hematopoietic progenitor cells after transduction.

Science.gov (United States)

Fisher-Adams, G; Wong, K K; Podsakoff, G; Forman, S J; Chatterjee, S

1996-07-15

Gene transfer vectors based on adeno-associated virus (AAV) appear promising because of their high transduction frequencies regardless of cell cycle status and ability to integrate into chromosomal DNA. We tested AAV-mediated gene transfer into a panel of human bone marrow or umbilical cord-derived CD34+ hematopoietic progenitor cells, using vectors encoding several transgenes under the control of viral and cellular promoters. Gene transfer was evaluated by (1) chromosomal integration of vector sequences and (2) analysis of transgene expression. Southern hybridization and fluorescence in situ hybridization analysis of transduced CD34 genomic DNA showed the presence of integrated vector sequences in chromosomal DNA in a portion of transduced cells and showed that integrated vector sequences were replicated along with cellular DNA during mitosis. Transgene expression in transduced CD34 cells in suspension cultures and in myeloid colonies differentiating in vitro from transduced CD34 cells approximated that predicted by the multiplicity of transduction. This was true in CD34 cells from different donors, regardless of the transgene or selective pressure. Comparisons of CD34 cell transduction either before or after cytokine stimulation showed similar gene transfer frequencies. Our findings suggest that AAV transduction of CD34+ hematopoietic progenitor cells is efficient, can lead to stable integration in a population of transduced cells, and may therefore provide the basis for safe and efficient ex vivo gene therapy of the hematopoietic system.

bantam miRNA is important for Drosophila blood cell homeostasis and a regulator of proliferation in the hematopoietic progenitor niche

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Lam, Victoria; Tokusumi, Tsuyoshi; Tokusumi, Yumiko; Schulz, Robert A., E-mail: rschulz@nd.edu

2014-10-24

Highlights: • bantam miRNA is endogenously expressed in the hematopoietic progenitor niche. • bantam is necessary and sufficient to induce cellular proliferation in the PSC. • bantam is upstream of the Insulin Receptor signaling pathway. • A model for positive regulation of hematopoietic niche growth is proposed. - Abstract: The Drosophila hematopoietic system is utilized in this study to gain novel insights into the process of growth control of the hematopoietic progenitor niche in blood development. The niche microenvironment is an essential component controlling the balance between progenitor populations and differentiated, mature blood cells and has been shown to lead to hematopoietic malignancies in humans when misregulated. MicroRNAs are one class of regulators associated with blood malignancies; however, there remains a relative paucity of information about the role of miRNAs in the niche. Here we demonstrate that bantam miRNA is endogenously active in the Drosophila hematopoietic progenitor niche, the posterior signaling center (PSC), and functions in the primary hematopoietic organ, the lymph gland, as a positive regulator of growth. Loss of bantam leads to a significant reduction in the PSC and overall lymph gland size, as well as a loss of the progenitor population and correlative premature differentiation of mature hemocytes. Interestingly, in addition to being essential for proper lymph gland development, we have determined bantam to be a novel upstream component of the insulin signaling cascade in the PSC and have unveiled dMyc as one factor central to bantam activity. These important findings identify bantam as a new hematopoietic regulator, place it in an evolutionarily conserved signaling pathway, present one way in which it is regulated, and provide a mechanism through which it facilitates cellular proliferation in the hematopoietic niche.

bantam miRNA is important for Drosophila blood cell homeostasis and a regulator of proliferation in the hematopoietic progenitor niche

International Nuclear Information System (INIS)

Lam, Victoria; Tokusumi, Tsuyoshi; Tokusumi, Yumiko; Schulz, Robert A.

2014-01-01

Highlights: • bantam miRNA is endogenously expressed in the hematopoietic progenitor niche. • bantam is necessary and sufficient to induce cellular proliferation in the PSC. • bantam is upstream of the Insulin Receptor signaling pathway. • A model for positive regulation of hematopoietic niche growth is proposed. - Abstract: The Drosophila hematopoietic system is utilized in this study to gain novel insights into the process of growth control of the hematopoietic progenitor niche in blood development. The niche microenvironment is an essential component controlling the balance between progenitor populations and differentiated, mature blood cells and has been shown to lead to hematopoietic malignancies in humans when misregulated. MicroRNAs are one class of regulators associated with blood malignancies; however, there remains a relative paucity of information about the role of miRNAs in the niche. Here we demonstrate that bantam miRNA is endogenously active in the Drosophila hematopoietic progenitor niche, the posterior signaling center (PSC), and functions in the primary hematopoietic organ, the lymph gland, as a positive regulator of growth. Loss of bantam leads to a significant reduction in the PSC and overall lymph gland size, as well as a loss of the progenitor population and correlative premature differentiation of mature hemocytes. Interestingly, in addition to being essential for proper lymph gland development, we have determined bantam to be a novel upstream component of the insulin signaling cascade in the PSC and have unveiled dMyc as one factor central to bantam activity. These important findings identify bantam as a new hematopoietic regulator, place it in an evolutionarily conserved signaling pathway, present one way in which it is regulated, and provide a mechanism through which it facilitates cellular proliferation in the hematopoietic niche

Using Proteomics to 1) Identify the Bone Marrow Homing Receptors Expressed on Human Hematopoietic Stem Cells and 2) Elucidate Critical Signaling Pathways Responsible for the Blockage of Hematopoietic Differentiation in Leukemia

KAUST Repository

Chin, Chee J.

2011-05-22

Successful hematopoiesis requires the trafficking of hematopoietic stem/progenitor cells (HSPCs) to their bone marrow (BM) niche, where they can differentiate to produce all blood lineages. Leukemia arises when there is a blockage of differentiation and uncontrolled proliferation in the hematopoietic cells during their development. To refine therapies for leukemia, this study sought to improve the homing of healthy donor HSPCs for better transplantation and to find new candidates for differentiating and blocking proliferation in leukemic cells. Characterizing the molecular effectors mediating cell migration forms the basis for improving clinical transplantation of HSPCs. E-selectin/ligand interactions play a critical role in the homing of HSPCs to the BM, however, the identity of E-selectin ligands remains elusive. We aimed to use mass spectrometry (MS) to fully analyze the E-selectin ligands expressed on HSPCs. Immunoprecipitation studies coupled with MS confirmed the expression of three known E-selectin ligands, the hematopoietic cell E-/L-selectin ligand (HCELL), P-selectin glycoprotein ligand-1 (PSGL-1) and CD43, and revealed the presence of many interesting candidates on HSPCs-like cell line and on primary human BM CD34+ cells. The MS dataset represents a rich resource for further characterization of E-selectin ligands, which will lead to improvement of HSPCs transplantation. 4 Understanding the critical pathways underlying the initiation and maintenance of leukemia plays a key role in treating acute myeloid leukemia (AML). Ligation of the glycoprotein, CD44, using monoclonal antibodies or its natural ligand, hyaluronic acid, drives the differentiation of immature leukemic cells towards mature terminally differentiated cells, inhibits their proliferation and in some case induces their apoptosis. The aim of this study is to characterize the phosphoproteome of AML cells in response to CD44-induced differentiation. This will afford novel insights into the

Human CD8 T cells generated in vitro from hematopoietic stem cells are functionally mature

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Zúñiga-Pflücker Juan

2011-03-01

Full Text Available Abstract Background T cell development occurs within the highly specialized thymus. Cytotoxic CD8 T cells are critical in adaptive immunity by targeting virally infected or tumor cells. In this study, we addressed whether functional CD8 T cells can be generated fully in vitro using human umbilical cord blood (UCB hematopoietic stem cells (HSCs in coculture with OP9-DL1 cells. Results HSC/OP9-DL1 cocultures supported the differentiation of CD8 T cells, which were TCR/CD3hi CD27hi CD1aneg and thus phenotypically resembled mature functional CD8 single positive thymocytes. These in vitro-generated T cells also appeared to be conventional CD8 cells, as they expressed high levels of Eomes and low levels of Plzf, albeit not identical to ex vivo UCB CD8 T cells. Consistent with the phenotypic and molecular characterization, upon TCR-stimulation, in vitro-generated CD8 T cells proliferated, expressed activation markers (MHC-II, CD25, CD38, secreted IFN-γ and expressed Granzyme B, a cytotoxic T-cell effector molecule. Conclusion Taken together, the ability to direct human hematopoietic stem cell or T-progenitor cells towards a mature functional phenotype raises the possibility of establishing cell-based treatments for T-immunodeficiencies by rapidly restoring CD8 effector function, thereby mitigating the risks associated with opportunistic infections.

CD34 Antigen and the MPL Receptor Expression Defines a Novel Class of Human Cord Blood-Derived Primitive Hematopoietic Stem Cells.

Science.gov (United States)

Matsuoka, Yoshikazu; Takahashi, Masaya; Sumide, Keisuke; Kawamura, Hiroshi; Nakatsuka, Ryusuke; Fujioka, Tatsuya; Sonoda, Yoshiaki

2017-06-09

In the murine hematopoietic stem cell (HSC) compartment, thrombopoietin (THPO)/MPL (THPO receptor) signaling plays an important role in the maintenance of adult quiescent HSCs. However, the role of THPO/MPL signaling in the human primitive HSC compartment has not yet been elucidated. We have identified very primitive human cord blood (CB)-derived CD34- severe combined immunodeficiency (SCID)-repopulating cells (SRCs) using the intra-bone marrow injection method. In this study, we investigated the roles of the MPL expression in the human primitive HSC compartment. The SRC activities of the highly purified CB-derived 18Lin-CD34+/-MPL+/- cells were analyzed using NOG mice. In the primary recipient mice, nearly all mice that received CD34+/-MPL+/- cells were repopulated with human CD45+ cells. Nearly all of these mice that received CD34+MPL+/- and CD34-MPL- cells showed a secondary repopulation. Interestingly, the secondary recipient mice that received CD34+/-MPL- cells showed a distinct tertiary repopulation. These results clearly indicate that the CD34+/- SRCs not expressing MPL sustain a long-term (LT) (>1 year) human cell repopulation in NOG mice. Moreover, CD34- SRCs generate CD34+CD38-CD90+ SRCs in vitro and in vivo. These findings provide a new concept that CD34-MPL- SRCs reside at the apex of the human HSC hierarchy.

Correction of mutant Fanconi anemia gene by homologous recombination in human hematopoietic cells using adeno-associated virus vector.

Science.gov (United States)

Paiboonsukwong, Kittiphong; Ohbayashi, Fumi; Shiiba, Haruka; Aizawa, Emi; Yamashita, Takayuki; Mitani, Kohnosuke

2009-11-01

Adeno-associated virus (AAV) vectors have been shown to correct a variety of mutations in human cells by homologous recombination (HR) at high rates, which can overcome insertional mutagenesis and transgene silencing, two of the major hurdles in conventional gene addition therapy of inherited diseases. We examined an ability of AAV vectors to repair a mutation in human hematopoietic cells by HR. We infected a human B-lymphoblastoid cell line (BCL) derived from a normal subject with an AAV, which disrupts the hypoxanthine phosphoribosyl transferase1 (HPRT1) locus, to measure the frequency of AAV-mediated HR in BCL cells. We subsequently constructed an AAV vector encoding the normal sequences from the Fanconi anemia group A (FANCA) locus to correct a mutation in the gene in BCL derived from a FANCA patient. Under optimal conditions, approximately 50% of BCL cells were transduced with an AAV serotype 2 (AAV-2) vector. In FANCA BCL cells, up to 0.016% of infected cells were gene-corrected by HR. AAV-mediated restoration of normal genotypic and phenotypic characteristics in FANCA-mutant cells was confirmed at the DNA, protein and functional levels. The results obtained in the present study indicate that AAV vectors may be applicable for gene correction therapy of inherited hematopoietic disorders.

Hematopoietic stem cells transplant in patients with common variable immunodeficiency. Is a therapeutic option?

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Julio César Cambray-Gutiérrez

2017-02-01

Full Text Available Background: Patients with common variable immunodeficiency show higher incidence of sinopulmonary and gastrointestinal infections, as well as lymphoproliferative and autoimmune diseases. The treatment of choice is replacement therapy with human gamma-globulin. Hematopoietic stem cell transplantation is a non-conventional therapeutic modality. Clinical case: Twenty-six-year old woman with no family or hereditary history of primary immune deficiencies or consanguinity, with repeated episodes of otitis, sinusitis, gastroenteritis and bronchitis since childhood. At adolescence, she was diagnosed with common variable immunodeficiency; she was prescribed intravenous gamma-globulin, broad-spectrum antimicrobials and macrolides. At 22 years of age, she underwent hematopoietic stem cell transplantation owing to continued severe infections. At 4 months, post-transplantation she was diagnosed with hypothyroidism and ovarian insufficiency. During the following 3 years, she had no infections, but at 25 years of age she had immune thrombocytopenic purpura diagnosed, which persists together with Raynaud’s disease and upper respiratory tract persistent infections. At the moment of this report she is being treated with intravenous gamma-globulin and receiving prophylaxis with clarithromycin, without steroids or danazol. Conclusions: Given the high rate of morbidity and mortality associated and immune reconstitution failure, hematopoietic stem cell transplantation should be carefully evaluated in patients with treatment-unresponsive infections or lymphoproliferative disorders.

Generation of hematopoietic stem cells from human embryonic stem cells using a defined, stepwise, serum-free, and serum replacement-free monolayer culture method.

Science.gov (United States)

Kim, So-Jung; Jung, Ji-Won; Ha, Hye-Yeong; Koo, Soo Kyung; Kim, Eung-Gook; Kim, Jung-Hyun

2017-03-01

Embryonic stem cells (ESCs) can be expanded infinitely in vitro and have the potential to differentiate into hematopoietic stem cells (HSCs); thus, they are considered a useful source of cells for HSC production. Although several technical in vitro methods for engineering HSCs from pluripotent stem cells have been developed, clinical application of HSCs engineered from pluripotent stem cells is restricted because of the possibility of xenogeneic contamination resulting from the use of murine materials. Human ESCs (CHA-hES15) were cultured on growth factor-reduced Matrigel-coated dishes in the mTeSR1 serum-free medium. When the cells were 70% confluent, we initiated HSC differentiation by three methods involving (1) knockout serum replacement (KSR), cytokines, TGFb1, EPO, and FLT3L; (2) KSR, cytokines, and bFGF; or (3) cytokines and bFGF. Among the three differentiation methods, the minimal number of cytokines without KSR resulted in the greatest production of HSCs. The optimized method resulted in a higher proportion of CD34 + CD43 + hematopoietic progenitor cells (HPCs) and CD34 + CD45 + HPCs compared to the other methods. In addition, the HSCs showed the potential to differentiate into multiple lineages of hematopoietic cells in vitro . In this study, we optimized a two-step, serum-free, animal protein-free, KSR-free, feeder-free, chemically defined monolayer culture method for generation of HSCs and hematopoietic stem and progenitor cells (HSPCs) from human ESCs.

A stable and reproducible human blood-brain barrier model derived from hematopoietic stem cells.

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Romeo Cecchelli

Full Text Available The human blood brain barrier (BBB is a selective barrier formed by human brain endothelial cells (hBECs, which is important to ensure adequate neuronal function and protect the central nervous system (CNS from disease. The development of human in vitro BBB models is thus of utmost importance for drug discovery programs related to CNS diseases. Here, we describe a method to generate a human BBB model using cord blood-derived hematopoietic stem cells. The cells were initially differentiated into ECs followed by the induction of BBB properties by co-culture with pericytes. The brain-like endothelial cells (BLECs express tight junctions and transporters typically observed in brain endothelium and maintain expression of most in vivo BBB properties for at least 20 days. The model is very reproducible since it can be generated from stem cells isolated from different donors and in different laboratories, and could be used to predict CNS distribution of compounds in human. Finally, we provide evidence that Wnt/β-catenin signaling pathway mediates in part the BBB inductive properties of pericytes.

Plerixafor (a CXCR4 antagonist following myeloablative allogeneic hematopoietic stem cell transplantation enhances hematopoietic recovery

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Michael M. B. Green

2016-08-01

Full Text Available Abstract Background The binding of CXCR4 with its ligand (stromal-derived factor-1 maintains hematopoietic stem/progenitor cells (HSPCs in a quiescent state. We hypothesized that blocking CXCR4/SDF-1 interaction after hematopoietic stem cell transplantation (HSCT promotes hematopoiesis by inducing HSC proliferation. Methods We conducted a phase I/II trial of plerixafor on hematopoietic cell recovery following myeloablative allogeneic HSCT. Patients with hematologic malignancies receiving myeloablative conditioning were enrolled. Plerixafor 240 μg/kg was administered subcutaneously every other day beginning day +2 until day +21 or until neutrophil recovery. The primary efficacy endpoints of the study were time to absolute neutrophil count >500/μl and platelet count >20,000/μl. The cumulative incidence of neutrophil and platelet engraftment of the study cohort was compared to that of a cohort of 95 allogeneic peripheral blood stem cell transplant recipients treated during the same period of time and who received similar conditioning and graft-versus-host disease prophylaxis. Results Thirty patients received plerixafor following peripheral blood stem cell (n = 28 (PBSC or bone marrow (n = 2 transplantation. Adverse events attributable to plerixafor were mild and indistinguishable from effects of conditioning. The kinetics of neutrophil and platelet engraftment, as demonstrated by cumulative incidence, from the 28 study subjects receiving PBSC showed faster neutrophil (p = 0.04 and platelet recovery >20 K (p = 0.04 compared to the controls. Conclusions Our study demonstrated that plerixafor can be given safely following myeloablative HSCT. It provides proof of principle that blocking CXCR4 after HSCT enhances hematopoietic recovery. Larger, confirmatory studies in other settings are warranted. Trial registration ClinicalTrials.gov NCT01280955

In Vitro Large Scale Production of Human Mature Red Blood Cells from Hematopoietic Stem Cells by Coculturing with Human Fetal Liver Stromal Cells

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Jiafei Xi

2013-01-01

Full Text Available In vitro models of human erythropoiesis are useful in studying the mechanisms of erythroid differentiation in normal and pathological conditions. Here we describe an erythroid liquid culture system starting from cord blood derived hematopoietic stem cells (HSCs. HSCs were cultured for more than 50 days in erythroid differentiation conditions and resulted in a more than 109-fold expansion within 50 days under optimal conditions. Homogeneous erythroid cells were characterized by cell morphology, flow cytometry, and hematopoietic colony assays. Furthermore, terminal erythroid maturation was improved by cosculturing with human fetal liver stromal cells. Cocultured erythroid cells underwent multiple maturation events, including decrease in size, increase in glycophorin A expression, and nuclear condensation. This process resulted in extrusion of the pycnotic nuclei in up to 80% of the cells. Importantly, they possessed the capacity to express the adult definitive β-globin chain upon further maturation. We also show that the oxygen equilibrium curves of the cord blood-differentiated red blood cells (RBCs are comparable to normal RBCs. The large number and purity of erythroid cells and RBCs produced from cord blood make this method useful for fundamental research in erythroid development, and they also provide a basis for future production of available RBCs for transfusion.

Differential Reponses of Hematopoietic Stem and Progenitor Cells to mTOR Inhibition

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Aimin Yang

2015-01-01

Full Text Available Abnormal activation of the mammalian target of rapamycin (mTOR signaling pathway has been observed in a variety of human cancers. Therefore, targeting of the mTOR pathway is an attractive strategy for cancer treatment and several mTOR inhibitors, including AZD8055 (AZD, a novel dual mTORC1/2 inhibitor, are currently in clinical trials. Although bone marrow (BM suppression is one of the primary side effects of anticancer drugs, it is not known if pharmacological inhibition of dual mTORC1/2 affects BM hematopoietic stem and progenitor cells (HSPCs function and plasticity. Here we report that dual inhibition of mTORC1/2 by AZD or its analogue (KU-63794 depletes mouse BM Lin−Sca-1+c-Kit+ cells in cultures via the induction of apoptotic cell death. Subsequent colony-forming unit (CFU assays revealed that inhibition of mTORC1/2 suppresses the clonogenic function of hematopoietic progenitor cells (HPCs in a dose-dependent manner. Surprisingly, we found that dual inhibition of mTORC1/2 markedly inhibits the growth of day-14 cobblestone area-forming cells (CAFCs but enhances the generation of day-35 CAFCs. Given the fact that day-14 and day-35 CAFCs are functional surrogates of HPCs and hematopoietic stem cells (HSCs, respectively, these results suggest that dual inhibition of mTORC1/2 may have distinct effects on HPCs versus HSCs.

Not just a marker: CD34 on human hematopoietic stem/progenitor cells dominates vascular selectin binding along with CD44

KAUST Repository

Abu Samra, Dina Bashir Kamil; Aleisa, Fajr A; Al-Amoodi, Asma S.; Jalal Ahmed, Heba M.; Chin, Chee Jia; AbuElela, Ayman; Bergam, Ptissam; Sougrat, Rachid; Merzaban, Jasmeen

2017-01-01

CD34 is routinely used to identify and isolate human hematopoietic stem/progenitor cells (HSPCs) for use clinically in bone marrow transplantation, but its function on these cells remains elusive. Glycoprotein ligands on HSPCs help guide their migration to specialized microvascular beds in the bone marrow that express vascular selectins (E- and P-selectin). Here, we show that HSPC-enriched fractions from human hematopoietic tissue expressing CD34 (CD34pos) bound selectins, whereas those lacking CD34 (CD34neg) did not. An unbiased proteomics screen identified potential glycoprotein ligands on CD34pos cells revealing CD34 itself as a major vascular selectin ligand. Biochemical and CD34 knockdown analyses highlight a key role for CD34 in the first prerequisite step of cell migration, suggesting that it is not just a marker on these cells. Our results also entice future potential strategies to investigate the glycoforms of CD34 that discriminate normal HSPCs from leukemic cells and to manipulate CD34neg HSPC-enriched bone marrow or cord blood populations as a source of stem cells for clinical use.

Not just a marker: CD34 on human hematopoietic stem/progenitor cells dominates vascular selectin binding along with CD44

KAUST Repository

Abu Samra, Dina Bashir Kamil

2017-12-27

CD34 is routinely used to identify and isolate human hematopoietic stem/progenitor cells (HSPCs) for use clinically in bone marrow transplantation, but its function on these cells remains elusive. Glycoprotein ligands on HSPCs help guide their migration to specialized microvascular beds in the bone marrow that express vascular selectins (E- and P-selectin). Here, we show that HSPC-enriched fractions from human hematopoietic tissue expressing CD34 (CD34pos) bound selectins, whereas those lacking CD34 (CD34neg) did not. An unbiased proteomics screen identified potential glycoprotein ligands on CD34pos cells revealing CD34 itself as a major vascular selectin ligand. Biochemical and CD34 knockdown analyses highlight a key role for CD34 in the first prerequisite step of cell migration, suggesting that it is not just a marker on these cells. Our results also entice future potential strategies to investigate the glycoforms of CD34 that discriminate normal HSPCs from leukemic cells and to manipulate CD34neg HSPC-enriched bone marrow or cord blood populations as a source of stem cells for clinical use.

Mechanism of recombinant human bone morphogenetic protein-2 in repairing hematopoietic injury in mice exposed to γ-rays

International Nuclear Information System (INIS)

Liu Shuibing; Hu Peizhen; Hou Ying; Li Xubo; Tian Qiong; Shi Mei

2009-01-01

Objective: To investigate the mechanism of recombinant human bone morphogenetic protein-2 (rhBMP-2) in repairing hematopoietic injury in mice irradiated with γ-ray. To prepare SRY gene probe and study the effect of rhBMP-2 in repairing hematopoietic injury in mice by in situ hybridization. Methods: Twenty-two BALB/c female mice were randomly divided into the irradiated group and BMP treated group, respectively. Bone marrow cells of normal male mice were transplanted into 22 female mice post-irradiation to 8.5 Gy of 60 Co γ rays. The left femurs of the survived female mice were re-irradiated with 9 Gy 14 days later. Mice in BMP treated group were given rhBMP-2 20 mg/kg while those in control group were treated with 0.9% saline by intraperitoneal injection every day for 6 days. These mice were killed 14 days later and paraffin sections of femurs were made. The SRY gene was detected with in situ hybridization. Results: There were more positive blots in the left femurs of the mice in irradiated group than those in BMP treated group (T=155.0, P 0.05). The number of positive blots in the left femurs of the mice in BMPtreated group was significantly less than those in the right femurs of the mice in two groups (T=155.0, 55.0, P<0.05). Conclusions: No donor cell of male mice was detected in the left femurs of BMP treated group, suggesting that rhBMP-2 promoted the restoration of residuary bone marrow cells. Thus, rhBMP-2 promotes the proliferation or differentiation of residuary mesenchymal stem cells, improves hematopoietic microenvironment and accelerates the hematopoietic restoration. (authors)

Symptoms after hospital discharge following hematopoietic stem cell transplantation

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Gamze Oguz

2014-01-01

Full Text Available Aims: The purposes of this study were to assess the symptoms of hematopoietic stem cell transplant patients after hospital discharge, and to determine the needs of transplant patients for symptom management. Materials and Methods: The study adopted a descriptive design. The study sample comprised of 66 hematopoietic stem cell transplant patients. The study was conducted in Istanbul. Data were collected using Patient Information Form and Memorial Symptom Assessment Scale (MSAS. Results: The frequency of psychological symptoms in hematopoietic stem cell transplant patients after discharge period (PSYCH subscale score 2.11 (standard deviation (SD = 0.69, range: 0.93-3.80 was higher in hematopoietic stem cell transplant patients than frequency of physical symptoms (PHYS subscale score: 1.59 (SD = 0.49, range: 1.00-3.38. Symptom distress caused by psychological and physical symptoms were at moderate level (Mean = 1.91, SD = 0.60, range: 0.95-3.63 and most distressing symptoms were problems with sexual interest or activity, difficulty sleeping, and diarrhea. Patients who did not have an additional chronic disease obtained higher MSAS scores. University graduates obtained higher Global Distress Index (GDI subscale and total MSAS scores with comparison to primary school graduates. Total MSAS, MSAS-PHYS subscale, and MSAS-PSYCH subscale scores were higher in patients with low level of income (P < 0.05. The patients (98.5% reported to receive education about symptom management after hospital discharge. Conclusions: Hematopoietic stem cell transplant patients continue to experience many distressing physical or psychological symptoms after discharge and need to be supported and educated for the symptom management.

Deletion of the LTR enhancer/promoter has no impact on the integration profile of MLV vectors in human hematopoietic progenitors.

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Arianna Moiani

Full Text Available Moloney murine leukemia virus (MLV-derived gamma-retroviral vectors integrate preferentially near transcriptional regulatory regions in the human genome, and are associated with a significant risk of insertional gene deregulation. Self-inactivating (SIN vectors carry a deletion of the U3 enhancer and promoter in the long terminal repeat (LTR, and show reduced genotoxicity in pre-clinical assays. We report a high-definition analysis of the integration preferences of a SIN MLV vector compared to a wild-type-LTR MLV vector in the genome of CD34(+ human hematopoietic stem/progenitor cells (HSPCs. We sequenced 13,011 unique SIN-MLV integration sites and compared them to 32,574 previously generated MLV sites in human HSPCs. The SIN-MLV vector recapitulates the integration pattern observed for MLV, with the characteristic clustering of integrations around enhancer and promoter regions associated to H3K4me3 and H3K4me1 histone modifications, specialized chromatin configurations (presence of the H2A.Z histone variant and binding of RNA Pol II. SIN-MLV and MLV integration clusters and hot spots overlap in most cases and are generated at a comparable frequency, indicating that the reduced genotoxicity of SIN-MLV vectors in hematopoietic cells is not due to a modified integration profile.

Radioresistant canine hematopoietic cells

International Nuclear Information System (INIS)

Kawakami, T.G.; Shimizu, J.; Rosenblatt, L.S.; Goldman, M.

1987-01-01

Survival of dogs that are continuously exposed to a moderate dose-rate of gamma radiation (10 cGy/day) is dependent on the age of the dog at the time of exposure. Most dogs exposed postpartum to gamma radiation suffered from suppressed hematopoiesis and died of aplasia. On the other hand, none of the in utero-exposed dogs suffered from suppressed hematopoiesis and most became long-term survivors, tolerating 10-fold greater total dose, but dying of myeloproliferative disease (MPD). Using acute gamma irradiation of hematopoietic cells and colony forming unit cell assay (CFU), they observed that a canine hematopoietic cell line established from a myeloid leukemic dog that was a long-term survivor of continuous irradiation was approximately 4-fold more radioresistant than a hematopoietic cell line established from a dog with nonradiation-induced myeloid leukemia or hematopoietic cells from normal canine bone marrow. In utero dogs that are long-term survivors of continuous irradiation have radioresistant hematopoietic cells, and radioresistance that is a constitutive property of the cells

Generation of mature T cells from human hematopoietic stem and progenitor cells in artificial thymic organoids.

Science.gov (United States)

Seet, Christopher S; He, Chongbin; Bethune, Michael T; Li, Suwen; Chick, Brent; Gschweng, Eric H; Zhu, Yuhua; Kim, Kenneth; Kohn, Donald B; Baltimore, David; Crooks, Gay M; Montel-Hagen, Amélie

2017-05-01

Studies of human T cell development require robust model systems that recapitulate the full span of thymopoiesis, from hematopoietic stem and progenitor cells (HSPCs) through to mature T cells. Existing in vitro models induce T cell commitment from human HSPCs; however, differentiation into mature CD3 + TCR-αβ + single-positive CD8 + or CD4 + cells is limited. We describe here a serum-free, artificial thymic organoid (ATO) system that supports efficient and reproducible in vitro differentiation and positive selection of conventional human T cells from all sources of HSPCs. ATO-derived T cells exhibited mature naive phenotypes, a diverse T cell receptor (TCR) repertoire and TCR-dependent function. ATOs initiated with TCR-engineered HSPCs produced T cells with antigen-specific cytotoxicity and near-complete lack of endogenous TCR Vβ expression, consistent with allelic exclusion of Vβ-encoding loci. ATOs provide a robust tool for studying human T cell differentiation and for the future development of stem-cell-based engineered T cell therapies.

Modulation of Hematopoietic Lineage Specification Impacts TREM2 Expression in Microglia-Like Cells Derived From Human Stem Cells.

Science.gov (United States)

Amos, Peter J; Fung, Susan; Case, Amanda; Kifelew, Jerusalem; Osnis, Leah; Smith, Carole L; Green, Kevin; Naydenov, Alipi; Aloi, Macarena; Hubbard, Jesse J; Ramakrishnan, Aravind; Garden, Gwenn A; Jayadev, Suman

2017-01-01

Microglia are the primary innate immune cell type in the brain, and their dysfunction has been linked to a variety of central nervous system disorders. Human microglia are extraordinarily difficult to obtain for experimental investigation, limiting our ability to study the impact of human genetic variants on microglia functions. Previous studies have reported that microglia-like cells can be derived from human monocytes or pluripotent stem cells. Here, we describe a reproducible relatively simple method for generating microglia-like cells by first deriving embryoid body mesoderm followed by exposure to microglia relevant cytokines. Our approach is based on recent studies demonstrating that microglia originate from primitive yolk sac mesoderm distinct from peripheral macrophages that arise during definitive hematopoiesis. We hypothesized that functional microglia could be derived from human stem cells by employing BMP-4 mesodermal specification followed by exposure to microglia-relevant cytokines, M-CSF, GM-CSF, IL-34, and TGF-β. Using immunofluorescence microscopy, flow cytometry, and reverse transcription polymerase chain reaction, we observed cells with microglia morphology expressing a repertoire of markers associated with microglia: Iba1, CX3CR1, CD11b, TREM2, HexB, and P2RY12. These microglia-like cells maintain myeloid functional phenotypes including Aβ peptide phagocytosis and induction of pro-inflammatory gene expression in response to lipopolysaccharide stimulation. Addition of small molecules BIO and SB431542, previously demonstrated to drive definitive hematopoiesis, resulted in decreased surface expression of TREM2. Together, these data suggest that mesodermal lineage specification followed by cytokine exposure produces microglia-like cells in vitro from human pluripotent stem cells and that this phenotype can be modulated by factors influencing hematopoietic lineage in vitro.

Gene expression profiling in the inductive human hematopoietic microenvironment

International Nuclear Information System (INIS)

Zhao Yongjun; Chen, Edwin; Li Liheng; Gong Baiwei; Xie Wei; Nanji, Shaherose; Dube, Ian D.; Hough, Margaret R.

2004-01-01

Human hematopoietic stem cells (HSCs) and their progenitors can be maintained in vitro in long-term bone marrow cultures (LTBMCs) in which constituent HSCs can persist within the adherent layers for up to 2 months. Media replenishment of LTBMCs has been shown to induce transition of HSCs from a quiescent state to an active cycling state. We hypothesize that the media replenishment of the LTBMCs leads to the activation of important regulatory genes uniquely involved in HSC proliferation and differentiation. To profile the gene expression changes associated with HSC activation, we performed suppression subtractive hybridization (SSH) on day 14 human LTBMCs following 1-h media replenishment and on unmanipulated controls. The generated SSH library contained 191 differentially up-regulated expressed sequence tags (ESTs), the majority corresponding to known genes related to various intracellular processes, including signal transduction pathways, protein synthesis, and cell cycle regulation. Nineteen ESTs represented previously undescribed sequences encoding proteins of unknown function. Differential up-regulation of representative genes, including IL-8, IL-1, putative cytokine 21/HC21, MAD3, and a novel EST was confirmed by semi-quantitative RT-PCR. Levels of fibronectin, G-CSF, and stem cell factor also increased in the conditioned media of LTBMCs as assessed by ELISA, indicating increased synthesis and secretion of these factors. Analysis of our library provides insights into some of the immediate early gene changes underlying the mechanisms by which the stromal elements within the LTBMCs contribute to the induction of HSC activation and provides the opportunity to identify as yet unrecognized factors regulating HSC activation in the LTBMC milieu

The fps/fes proto-oncogene regulates hematopoietic lineage output.

Science.gov (United States)

Sangrar, Waheed; Gao, Yan; Zirngibl, Ralph A; Scott, Michelle L; Greer, Peter A

2003-12-01

The fps/fes proto-oncogene is abundantly expressed in myeloid cells, and the Fps/Fes cytoplasmic protein-tyrosine kinase is implicated in signaling downstream from hematopoietic cytokines, including interleukin-3 (IL-3), granulocyte-macrophage colony-stimulating factor (GM-CSF), and erythropoietin (EPO). Studies using leukemic cell lines have previously suggested that Fps/Fes contributes to granulomonocytic differentiation, and that it might play a more selective role in promoting survival and differentiation along the monocytic pathway. In this study we have used a genetic approach to explore the role of Fps/Fes in hematopoiesis. We used transgenic mice that tissue-specifically express a mutant human fps/fes transgene (fps(MF)) that was engineered to encode Fps/Fes kinase that is activated through N-terminal myristoylation (MFps). Hematopoietic function was assessed using lineage analysis, hematopoietic progenitor cell colony-forming assays, and biochemical approaches. fps(MF) transgenic mice displayed a skewed hematopoietic output reflected by increased numbers of circulating granulocytic and monocytic cells and a corresponding decrease in lymphoid cells. Bone marrow colony assays of progenitor cells revealed a significant increase in the number of both granulomonocytic and multi-lineage progenitors. A molecular analysis of signaling in mature monocytic cells showed that MFps promoted GM-CSF-induced STAT3, STAT5, and ERK1/2 activation. These observations support a role for Fps/Fes in signaling pathways that contribute to lineage determination at the level of multi-lineage hematopoietic progenitors as well as the more committed granulomonocytic progenitors.

In vitro effects of recombinant human stem cell factor on hematopoietic cells from patients with acute radiation sickness

International Nuclear Information System (INIS)

Li Chuansheng; Cheng Tao; Xu Yanqun

1994-01-01

The effects of rhSCF, rhPIXY 321, rhGM-CSF and rhIL-3 on clonal proliferation of hematopoietic cells from five cases of acute radiation sickness were studied. The results showed that rhSCF could stimulate clonal proliferation of normal hematopoietic cells and the best results were obtained when the concentration of rhSCF was 5 x 10 4 ng/L. Clonal proliferation of hematopoietic cells from four cases of acute radiation sickness was stimulated while that from one case was inhibited. Moreover, the responsiveness of cells to rhSCF was correlated with the doses of radiation. Analysis of cell surface antigen, cell morphology and histochemistry revealed that rhSCF promoted predominantly the proliferation of granulocyte-macrophage lineage. rhSCF in combination with other three factors could further enhance the clonal proliferation of hematopoietic cells. The effects of rhPIXY 321, a fusion protein of GM-CSF and IL-3, were also analysed and found it to be a novel valuable hematopoietic growth factor

SBR-Blood: systems biology repository for hematopoietic cells.

Science.gov (United States)

Lichtenberg, Jens; Heuston, Elisabeth F; Mishra, Tejaswini; Keller, Cheryl A; Hardison, Ross C; Bodine, David M

2016-01-04

Extensive research into hematopoiesis (the development of blood cells) over several decades has generated large sets of expression and epigenetic profiles in multiple human and mouse blood cell types. However, there is no single location to analyze how gene regulatory processes lead to different mature blood cells. We have developed a new database framework called hematopoietic Systems Biology Repository (SBR-Blood), available online at http://sbrblood.nhgri.nih.gov, which allows user-initiated analyses for cell type correlations or gene-specific behavior during differentiation using publicly available datasets for array- and sequencing-based platforms from mouse hematopoietic cells. SBR-Blood organizes information by both cell identity and by hematopoietic lineage. The validity and usability of SBR-Blood has been established through the reproduction of workflows relevant to expression data, DNA methylation, histone modifications and transcription factor occupancy profiles. Published by Oxford University Press on behalf of Nucleic Acids Research 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Molecular signatures in childhood acute leukemia and their correlations to expression patterns in normal hematopoietic subpopulations.

Science.gov (United States)

Andersson, Anna; Olofsson, Tor; Lindgren, David; Nilsson, Björn; Ritz, Cecilia; Edén, Patrik; Lassen, Carin; Råde, Johan; Fontes, Magnus; Mörse, Helena; Heldrup, Jesper; Behrendtz, Mikael; Mitelman, Felix; Höglund, Mattias; Johansson, Bertil; Fioretos, Thoas

2005-12-27

Global expression profiles of a consecutive series of 121 childhood acute leukemias (87 B lineage acute lymphoblastic leukemias, 11 T cell acute lymphoblastic leukemias, and 23 acute myeloid leukemias), six normal bone marrows, and 10 normal hematopoietic subpopulations of different lineages and maturations were ascertained by using 27K cDNA microarrays. Unsupervised analyses revealed segregation according to lineages and primary genetic changes, i.e., TCF3(E2A)/PBX1, IGH@/MYC, ETV6(TEL)/RUNX1(AML1), 11q23/MLL, and hyperdiploidy (>50 chromosomes). Supervised discriminatory analyses were used to identify differentially expressed genes correlating with lineage and primary genetic change. The gene-expression profiles of normal hematopoietic cells were also studied. By using principal component analyses (PCA), a differentiation axis was exposed, reflecting lineages and maturation stages of normal hematopoietic cells. By applying the three principal components obtained from PCA of the normal cells on the leukemic samples, similarities between malignant and normal cell lineages and maturations were investigated. Apart from showing that leukemias segregate according to lineage and genetic subtype, we provide an extensive study of the genes correlating with primary genetic changes. We also investigated the expression pattern of these genes in normal hematopoietic cells of different lineages and maturations, identifying genes preferentially expressed by the leukemic cells, suggesting an ectopic activation of a large number of genes, likely to reflect regulatory networks of pathogenetic importance that also may provide attractive targets for future directed therapies.

Recombinant TAT-BMI-1 fusion protein induces ex vivo expansion of human umbilical cord blood-derived hematopoietic stem cells.

Science.gov (United States)

Codispoti, Bruna; Rinaldo, Nicola; Chiarella, Emanuela; Lupia, Michela; Spoleti, Cristina Barbara; Marafioti, Maria Grazia; Aloisio, Annamaria; Scicchitano, Stefania; Giordano, Marco; Nappo, Giovanna; Lucchino, Valeria; Moore, Malcolm A S; Zhou, Pengbo; Mesuraca, Maria; Bond, Heather Mandy; Morrone, Giovanni

2017-07-04

Transplantation of hematopoietic stem cells (HSCs) is a well-established therapeutic approach for numerous disorders. HSCs are typically derived from bone marrow or peripheral blood after cytokine-induced mobilization. Umbilical cord blood (CB) represents an appealing alternative HSC source, but the small amounts of the individual CB units have limited its applications. The availability of strategies for safe ex vivo expansion of CB-derived HSCs (CB-HSCs) may allow to extend the use of these cells in adult patients and to avoid the risk of insufficient engraftment or delayed hematopoietic recovery.Here we describe a system for the ex vivo expansion of CB-HSCs based on their transient exposure to a recombinant TAT-BMI-1 chimeric protein. BMI-1 belongs to the Polycomb family of epigenetic modifiers and is recognized as a central regulator of HSC self-renewal. Recombinant TAT-BMI-1 produced in bacteria was able to enter the target cells via the HIV TAT-derived protein transduction peptide covalently attached to BMI-1, and conserved its biological activity. Treatment of CB-CD34+ cells for 3 days with repeated addition of 10 nM purified TAT-BMI-1 significantly enhanced total cell expansion as well as that of primitive hematopoietic progenitors in culture. Importantly, TAT-BMI-1-treated CB-CD34+ cells displayed a consistently higher rate of multi-lineage long-term repopulating activity in primary and secondary xenotransplants in immunocompromised mice. Thus, recombinant TAT-BMI-1 may represent a novel, effective reagent for ex vivo expansion of CB-HSC for therapeutic purposes.

Nutraceutical augmentation of circulating endothelial progenitor cells and hematopoietic stem cells in human subjects.

Science.gov (United States)

Mikirova, Nina A; Jackson, James A; Hunninghake, Ron; Kenyon, Julian; Chan, Kyle W H; Swindlehurst, Cathy A; Minev, Boris; Patel, Amit N; Murphy, Michael P; Smith, Leonard; Ramos, Famela; Ichim, Thomas E; Riordan, Neil H

2010-04-08

The medical significance of circulating endothelial or hematopoietic progenitors is becoming increasing recognized. While therapeutic augmentation of circulating progenitor cells using G-CSF has resulted in promising preclinical and early clinical data for several degenerative conditions, this approach is limited by cost and inability to perform chronic administration. Stem-Kine is a food supplement that was previously reported to augment circulating EPC in a pilot study. Here we report a trial in 18 healthy volunteers administered Stem-Kine twice daily for a 2 week period. Significant increases in circulating CD133 and CD34 cells were observed at days 1, 2, 7, and 14 subsequent to initiation of administration, which correlated with increased hematopoietic progenitors as detected by the HALO assay. Augmentation of EPC numbers in circulation was detected by KDR-1/CD34 staining and colony forming assays. These data suggest Stem-Kine supplementation may be useful as a stimulator of reparative processes associated with mobilization of hematopoietic and endothelial progenitors.

Nutraceutical augmentation of circulating endothelial progenitor cells and hematopoietic stem cells in human subjects

Directory of Open Access Journals (Sweden)

Minev Boris

2010-04-01

Full Text Available Abstract The medical significance of circulating endothelial or hematopoietic progenitors is becoming increasing recognized. While therapeutic augmentation of circulating progenitor cells using G-CSF has resulted in promising preclinical and early clinical data for several degenerative conditions, this approach is limited by cost and inability to perform chronic administration. Stem-Kine is a food supplement that was previously reported to augment circulating EPC in a pilot study. Here we report a trial in 18 healthy volunteers administered Stem-Kine twice daily for a 2 week period. Significant increases in circulating CD133 and CD34 cells were observed at days 1, 2, 7, and 14 subsequent to initiation of administration, which correlated with increased hematopoietic progenitors as detected by the HALO assay. Augmentation of EPC numbers in circulation was detected by KDR-1/CD34 staining and colony forming assays. These data suggest Stem-Kine supplementation may be useful as a stimulator of reparative processes associated with mobilization of hematopoietic and endothelial progenitors.

Failure in activation of the canonical NF-κB pathway by human T-cell leukemia virus type 1 Tax in non-hematopoietic cell lines

Energy Technology Data Exchange (ETDEWEB)

Mizukoshi, Terumi; Komori, Hideyuki; Mizuguchi, Mariko [Human Gene Sciences Center, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510 (Japan); Abdelaziz, Hussein [Human Gene Sciences Center, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510 (Japan); Department of Medical Biochemistry, Faculty of Medicine, Mansoura University, Mansoura (Egypt); Hara, Toshifumi [Human Gene Sciences Center, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510 (Japan); Higuchi, Masaya [Division of Virology, Niigata University Graduate School of Medical and Dental Sciences, Niigata (Japan); Tanaka, Yuetsu [Department of Immunology, Graduate School and Faculty of Medicine, Ryukyu University, Okinawa (Japan); Ohara, Yoshiro [Department of Microbiology, Kanazawa Medical University, Ishikawa (Japan); Funato, Noriko [Human Gene Sciences Center, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510 (Japan); Fujii, Masahiro [Division of Virology, Niigata University Graduate School of Medical and Dental Sciences, Niigata (Japan); Nakamura, Masataka, E-mail: naka.gene@tmd.ac.jp [Human Gene Sciences Center, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510 (Japan)

2013-09-01

Human T-cell leukemia virus type 1 (HTLV-1) Tax (Tax1) plays crucial roles in leukemogenesis in part through activation of NF-κB. In this study, we demonstrated that Tax1 activated an NF-κB binding (gpκB) site of the gp34/OX40 ligand gene in a cell type-dependent manner. Our examination showed that the gpκΒ site and authentic NF-κB (IgκB) site were activated by Tax1 in hematopoietic cell lines. Non-hematopoietic cell lines including hepatoma and fibroblast cell lines were not permissive to Tax1-mediated activation of the gpκB site, while the IgκB site was activated in those cells in association with binding of RelB. However RelA binding was not observed in the gpκB and IgκB sites. Our results suggest that HTLV-1 Tax1 fails to activate the canonical pathway of NF-κB in non-hematopoietic cell lines. Cell type-dependent activation of NF-κB by Tax1 could be associated with pathogenesis by HTLV-1 infection. - Highlights: • HTLV-1 Tax1 does not activate RelA of NF-κB in non-hematopoietic cell lines. • Tax1 activates the NF-κB non-canonical pathway in non-hematopoietic cell lines. • Tax1 does not induce RelA nuclear translocation in those cell lines, unlike TNFα. • The OX40L promoter κB site is activated by ectopic, but not endogenous, RelA.

Allogeneic hematopoietic stem-cell transplantation for leukocyte adhesion deficiency

DEFF Research Database (Denmark)

Qasim, Waseem; Cavazzana-Calvo, Marina; Davies, E Graham

2009-01-01

OBJECTIVES: Leukocyte adhesion deficiency is a rare primary immune disorder caused by defects of the CD18 beta-integrin molecule on immune cells. The condition usually presents in early infancy and is characterized by deep tissue infections, leukocytosis with impaired formation of pus, and delayed...... of leukocyte adhesion deficiency who underwent hematopoietic stem-cell transplantation between 1993 and 2007 was retrospectively analyzed. Data were collected by the registries of the European Society for Immunodeficiencies/European Group for Blood and Marrow Transplantation, and the Center for International......, with full donor engraftment in 17 cases, mixed multilineage chimerism in 7 patients, and mononuclear cell-restricted chimerism in an additional 3 cases. CONCLUSIONS: Hematopoietic stem-cell transplantation offers long-term benefit in leukocyte adhesion deficiency and should be considered as an early...

Early osteoinductive human bone marrow mesenchymal stromal/stem cells support an enhanced hematopoietic cell expansion with altered chemotaxis- and adhesion-related gene expression profiles

Energy Technology Data Exchange (ETDEWEB)

Sugino, Noriko [Department of Hematology/Oncology, Graduate School of Medicine, Kyoto University, Kyoto 606-8507 (Japan); Department of Transfusion Medicine and Cell Therapy, Kyoto University Hospital, Kyoto 606-8507 (Japan); Miura, Yasuo, E-mail: ym58f5@kuhp.kyoto-u.ac.jp [Department of Transfusion Medicine and Cell Therapy, Kyoto University Hospital, Kyoto 606-8507 (Japan); Yao, Hisayuki [Department of Transfusion Medicine and Cell Therapy, Kyoto University Hospital, Kyoto 606-8507 (Japan); Iwasa, Masaki; Fujishiro, Aya [Department of Transfusion Medicine and Cell Therapy, Kyoto University Hospital, Kyoto 606-8507 (Japan); Division of Gastroenterology and Hematology, Shiga University of Medical Science, Shiga 520-2192 (Japan); Fujii, Sumie [Department of Hematology/Oncology, Graduate School of Medicine, Kyoto University, Kyoto 606-8507 (Japan); Department of Transfusion Medicine and Cell Therapy, Kyoto University Hospital, Kyoto 606-8507 (Japan); Hirai, Hideyo [Department of Transfusion Medicine and Cell Therapy, Kyoto University Hospital, Kyoto 606-8507 (Japan); Takaori-Kondo, Akifumi [Department of Hematology/Oncology, Graduate School of Medicine, Kyoto University, Kyoto 606-8507 (Japan); Ichinohe, Tatsuo [Department of Hematology and Oncology, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima 734-8553 (Japan); Maekawa, Taira [Department of Transfusion Medicine and Cell Therapy, Kyoto University Hospital, Kyoto 606-8507 (Japan)

2016-01-22

Bone marrow (BM) microenvironment has a crucial role in supporting hematopoiesis. Here, by using a microarray analysis, we demonstrate that human BM mesenchymal stromal/stem cells (MSCs) in an early osteoinductive stage (e-MSCs) are characterized by unique hematopoiesis-associated gene expression with an enhanced hematopoiesis-supportive ability. In comparison to BM-MSCs without osteoinductive treatment, gene expression in e-MSCs was significantly altered in terms of their cell adhesion- and chemotaxis-related profiles, as identified with Gene Ontology and Gene Set Enrichment Analysis. Noteworthy, expression of the hematopoiesis-associated molecules CXCL12 and vascular cell adhesion molecule 1 was remarkably decreased in e-MSCs. e-MSCs supported an enhanced expansion of CD34{sup +} hematopoietic stem and progenitor cells, and generation of myeloid lineage cells in vitro. In addition, short-term osteoinductive treatment favored in vivo hematopoietic recovery in lethally irradiated mice that underwent BM transplantation. e-MSCs exhibited the absence of decreased stemness-associated gene expression, increased osteogenesis-associated gene expression, and apparent mineralization, thus maintaining the ability to differentiate into adipogenic cells. Our findings demonstrate the unique biological characteristics of e-MSCs as hematopoiesis-regulatory stromal cells at differentiation stage between MSCs and osteoprogenitor cells and have significant implications in developing new strategy for using pharmacological osteoinductive treatment to support hematopoiesis in hematopoietic stem and progenitor cell transplantation. - Highlights: • Human BM-MSCs in an early osteoinductive stage (e-MSCs) support hematopoiesis. • Adhesion- and chemotaxis-associated gene signatures are altered in e-MSCs. • Expression of CXCL12 and VCAM1 is remarkably decreased in e-MSCs. • e-MSCs are at differentiation stage between MSCs and osteoprogenitor cells. • Osteoinductive treatment

Gene expression profiling identifies HOXB4 as a direct downstream target of GATA-2 in human CD34+ hematopoietic cells.

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Tohru Fujiwara

Full Text Available Aplastic anemia is characterized by a reduced hematopoietic stem cell number. Although GATA-2 expression was reported to be decreased in CD34-positive cells in aplastic anemia, many questions remain regarding the intrinsic characteristics of hematopoietic stem cells in this disease. In this study, we identified HOXB4 as a downstream target of GATA-2 based on expression profiling with human cord blood-derived CD34-positive cells infected with control or GATA-2 lentiviral shRNA. To confirm the functional link between GATA-2 and HOXB4, we conducted GATA-2 gain-of-function and loss-of-function experiments, and HOXB4 promoter analysis, including luciferase assay, in vitro DNA binding analysis and quantitative ChIP analysis, using K562 and CD34-positive cells. The analyses suggested that GATA-2 directly regulates HOXB4 expression through the GATA sequence in the promoter region. Furthermore, we assessed GATA-2 and HOXB4 expression in CD34-positive cells from patients with aplastic anemia (n = 10 and idiopathic thrombocytopenic purpura (n = 13, and demonstrated that the expression levels of HOXB4 and GATA-2 were correlated in these populations (r = 0.6573, p<0.01. Our results suggested that GATA-2 directly regulates HOXB4 expression in hematopoietic stem cells, which may play an important role in the development and/or progression of aplastic anemia.

Novel pathways to erythropoiesis induced by dimerization of intracellular C-Mpl in human hematopoietic progenitors.

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Parekh, Chintan; Sahaghian, Arineh; Kim, William; Scholes, Jessica; Ge, Shundi; Zhu, Yuhua; Asgharzadeh, Shahab; Hollis, Roger; Kohn, Donald; Ji, Lingyun; Malvar, Jemily; Wang, Xiaoyan; Crooks, Gay

2012-04-01

The cytokine thrombopoietin (Tpo) plays a critical role in hematopoiesis by binding to the extracellular domain and inducing homodimerization of the intracellular signaling domain of its receptor, c-Mpl. Mpl homodimerization can also be accomplished by binding of a synthetic ligand to a constitutively expressed fusion protein F36VMpl consisting of a ligand binding domain (F36V) and the intracellular signaling domain of Mpl. Unexpectedly, in contrast to Tpo stimulation, robust erythropoiesis is induced after dimerization of F36VMpl in human CD34+ progenitor cells. The goal of this study was to define the hematopoietic progenitor stages at which dimerization of intracellular Mpl induces erythropoiesis and the downstream molecular events that mediate this unanticipated effect. Dimerization (in the absence of erythropoietin and other cytokines) in human common myeloid progenitors and megakaryocytic erythroid progenitors caused a significant increase in CD34+ cells (p Mpl in human myeloerythroid progenitors induces progenitor expansion and erythropoiesis through molecular mechanisms that are not shared by Tpo stimulation of endogenous Mpl. Copyright © 2012 AlphaMed Press.

Brief Reports: Nfix Promotes Survival of Immature Hematopoietic Cells via Regulation of c-Mpl.

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Hall, Trent; Walker, Megan; Ganuza, Miguel; Holmfeldt, Per; Bordas, Marie; Kang, Guolian; Bi, Wenjian; Palmer, Lance E; Finkelstein, David; McKinney-Freeman, Shannon

2018-02-12

Hematopoietic stem and progenitor cells (HSPCs) are necessary for life-long blood production and replenishment of the hematopoietic system during stress. We recently reported that nuclear factor I/X (Nfix) promotes HSPC survival post-transplant. Here, we report that ectopic expression of Nfix in primary mouse HSPCs extends their ex vivo culture from about 20 to 40 days. HSPCs overexpressing Nfix display hypersensitivity to supportive cytokines and reduced apoptosis when subjected to cytokine deprivation relative to controls. Ectopic Nfix resulted in elevated levels of c-Mpl transcripts and cell surface protein on primary murine HSPCs as well as increased phosphorylation of STAT5, which is known to be activated down-stream of c-MPL. Blocking c-MPL signaling by removal of thrombopoietin or addition of a c-MPL neutralizing antibody negated the antiapoptotic effect of Nfix overexpression on cultured HSPCs. Furthermore, NFIX was capable of binding to and transcriptionally activating a proximal c-Mpl promoter fragment. In sum, these data suggest that NFIX-mediated upregulation of c-Mpl transcription can protect primitive hematopoietic cells from stress ex vivo. Stem Cells 2018. © AlphaMed Press 2018.

Pluripotent stem cell models of Shwachman-Diamond syndrome reveal a common mechanism for pancreatic and hematopoietic dysfunction

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Tulpule, Asmin; Kelley, James M.; Lensch, M. William; McPherson, Jade; Park, In Hyun; Hartung, Odelya; Nakamura, Tomoka; Schlaeger, Thorsten M.; Shimamura, Akiko; Daley, George Q.

2013-01-01

Summary Shwachman-Diamond syndrome (SDS), a rare autosomal recessive disorder characterized by exocrine pancreatic insufficiency and hematopoietic dysfunction, is caused by mutations in the Shwachman-Bodian-Diamond syndrome (SBDS) gene. We created human pluripotent stem cell models of SDS by knock-down of SBDS in human embryonic stem cells (hESCs) and generation of induced pluripotent stem cell (iPSC) lines from two SDS patients. SBDS-deficient hESCs and iPSCs manifest deficits in exocrine pancreatic and hematopoietic differentiation in vitro, enhanced apoptosis and elevated protease levels in culture supernatants, which could be reversed by restoring SBDS protein expression through transgene rescue or by supplementing culture media with protease inhibitors. Protease-mediated auto-digestion provides a mechanistic link between the pancreatic and hematopoietic phenotypes in SDS, highlighting the utility of hESCs and iPSCs in obtaining novel insights into human disease. PMID:23602541

Caffeine affects the biological responses of human hematopoietic cells of myeloid lineage via downregulation of the mTOR pathway and xanthine oxidase activity

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Abooali, Maryam; Yasinska, Inna M.; Casely-Hayford, Maxwell A.; Berger, Steffen M.; Fasler-Kan, Elizaveta; Sumbayev, Vadim V.

2015-01-01

Correction of human myeloid cell function is crucial for the prevention of inflammatory and allergic reactions as well as leukaemia progression. Caffeine, a naturally occurring food component, is known to display anti-inflammatory effects which have previously been ascribed largely to its inhibitory actions on phosphodiesterase. However, more recent studies suggest an additional role in affecting the activity of the mammalian target of rapamycin (mTOR), a master regulator of myeloid cell translational pathways, although detailed molecular events underlying its mode of action have not been elucidated. Here, we report the cellular uptake of caffeine, without metabolisation, by healthy and malignant hematopoietic myeloid cells including monocytes, basophils and primary acute myeloid leukaemia mononuclear blasts. Unmodified caffeine downregulated mTOR signalling, which affected glycolysis and the release of pro-inflammatory/pro-angiogenic cytokines as well as other inflammatory mediators. In monocytes, the effects of caffeine were potentiated by its ability to inhibit xanthine oxidase, an enzyme which plays a central role in human purine catabolism by generating uric acid. In basophils, caffeine also increased intracellular cyclic adenosine monophosphate (cAMP) levels which further enhanced its inhibitory action on mTOR. These results demonstrate an important mode of pharmacological action of caffeine with potentially wide-ranging therapeutic impact for treating non-infectious disorders of the human immune system, where it could be applied directly to inflammatory cells. PMID:26384306

Improvement in the quality of hematopoietic prostaglandin D synthase crystals in a microgravity environment

International Nuclear Information System (INIS)

Tanaka, Hiroaki; Tsurumura, Toshiharu; Aritake, Kosuke; Furubayashi, Naoki; Takahashi, Sachiko; Yamanaka, Mari; Hirota, Erika; Sano, Satoshi; Sato, Masaru; Kobayashi, Tomoyuki; Tanaka, Tetsuo; Inaka, Koji; Urade, Yoshihiro

2011-01-01

Crystals of hematopoietic prostaglandin D synthase grown in microgravity show improved quality. Human hematopoietic prostaglandin synthase, one of the better therapeutic target enzymes for allergy and inflammation, was crystallized with 22 inhibitors and in three inhibitor-free conditions in microgravity. Most of the space-grown crystals showed better X-ray diffraction patterns than the terrestrially grown ones, indicating the advantage of a microgravity environment on protein crystallization, especially in the case of this protein

Staurosporine Increases Lentiviral Vector Transduction Efficiency of Human Hematopoietic Stem and Progenitor Cells

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Gretchen Lewis

2018-06-01

Full Text Available Lentiviral vector (LVV-mediated transduction of human CD34+ hematopoietic stem and progenitor cells (HSPCs holds tremendous promise for the treatment of monogenic hematological diseases. This approach requires the generation of a sufficient proportion of gene-modified cells. We identified staurosporine, a serine/threonine kinase inhibitor, as a small molecule that could be added to the transduction process to increase the proportion of genetically modified HSPCs by overcoming a LVV entry barrier. Staurosporine increased vector copy number (VCN approximately 2-fold when added to mobilized peripheral blood (mPB CD34+ cells prior to transduction. Limited staurosporine treatment did not affect viability of cells post-transduction, and there was no difference in in vitro colony formation compared to vehicle-treated cells. Xenotransplantation studies identified a statistically significant increase in VCN in engrafted human cells in mouse bone marrow at 4 months post-transplantation compared to vehicle-treated cells. Prostaglandin E2 (PGE2 is known to increase transduction efficiency of HSPCs through a different mechanism. Combining staurosporine and PGE2 resulted in further enhancement of transduction efficiency, particularly in short-term HSPCs. The combinatorial use of small molecules, such as staurosporine and PGE2, to enhance LVV transduction of human CD34+ cells is a promising method to improve transduction efficiency and subsequent potential therapeutic benefit of gene therapy drug products. Keywords: lentiviral, HSPC, transduction

Towards a clinically relevant lentiviral transduction protocol for primary human CD34 hematopoietic stem/progenitor cells.

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Michelle Millington

2009-07-01

Full Text Available Hematopoietic stem cells (HSC, in particular mobilized peripheral blood stem cells, represent an attractive target for cell and gene therapy. Efficient gene delivery into these target cells without compromising self-renewal and multi-potency is crucial for the success of gene therapy. We investigated factors involved in the ex vivo transduction of CD34(+ HSCs in order to develop a clinically relevant transduction protocol for gene delivery. Specifically sought was a protocol that allows for efficient transduction with minimal ex vivo manipulation without serum or other reagents of animal origin.Using commercially available G-CSF mobilized peripheral blood (PB CD34(+ cells as the most clinically relevant target, we systematically examined factors including the use of serum, cytokine combinations, pre-stimulation time, multiplicity of infection (MOI, transduction duration and the use of spinoculation and/or retronectin. A self-inactivating lentiviral vector (SIN-LV carrying enhanced green fluorescent protein (GFP was used as the gene delivery vehicle. HSCs were monitored for transduction efficiency, surface marker expression and cellular function. We were able to demonstrate that efficient gene transduction can be achieved with minimal ex vivo manipulation while maintaining the cellular function of transduced HSCs without serum or other reagents of animal origin.This study helps to better define factors relevant towards developing a standard clinical protocol for the delivery of SIN-LV into CD34(+ cells.

Umbilical Cord-Derived Mesenchymal Stem Cells for Hematopoietic Stem Cell Transplantation

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Yu-Hua Chao

2012-01-01

Full Text Available Hematopoietic stem cell transplantation (HSCT is becoming an effective therapeutic modality for a variety of diseases. Mesenchymal stem cells (MSCs can be used to enhance hematopoietic engraftment, accelerate lymphocyte recovery, reduce the risk of graft failure, prevent and treat graft-versus-host disease, and repair tissue damage in patients receiving HSCT. Till now, most MSCs for human clinical application have been derived from bone marrow. However, acquiring bone-marrow-derived MSCs involves an invasive procedure. Umbilical cord is rich with MSCs. Compared to bone-marrow-derived MSCs, umbilical cord-derived MSCs (UCMSCs are easier to obtain without harm to the donor and can proliferate faster. No severe adverse effects were noted in our previous clinical application of UCMSCs in HSCT. Accordingly, application of UCMSCs in humans appears to be feasible and safe. Further studies are warranted.

AF10 plays a key role in the survival of uncommitted hematopoietic cells.

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Raquel Chamorro-Garcia

Full Text Available Hematopoiesis is a complex process regulated by both cell intrinsic and cell extrinsic factors. Alterations in the expression of critical genes during hematopoiesis can modify the balance between stem cell differentiation and proliferation, and may ultimately give rise to leukemia and other diseases. AF10 is a transcription factor that has been implicated in the development of leukemia following chromosomal rearrangements between the AF10 gene and one of at least two other genes, MLL and CALM. The link between AF10 and leukemia, together with the known interactions between AF10 and hematopoietic regulators, suggests that AF10 may be important in hematopoiesis and in leukemic transformation. Here we show that AF10 is important for proper hematopoietic differentiation. The induction of hematopoietic differentiation in both human hematopoietic cell lines and murine total bone marrow cells triggers a decrease of AF10 mRNA and protein levels, particularly in stem cells and multipotent progenitors. Gain- and loss-of-function studies demonstrate that over- or under-expression of AF10 leads to apoptotic cell death in stem cells and multipotent progenitors. We conclude that AF10 plays a key role in the maintenance of multipotent hematopoietic cells.

CTCF and CohesinSA-1 Mark Active Promoters and Boundaries of Repressive Chromatin Domains in Primary Human Erythroid Cells.

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Laurie A Steiner

Full Text Available CTCF and cohesinSA-1 are regulatory proteins involved in a number of critical cellular processes including transcription, maintenance of chromatin domain architecture, and insulator function. To assess changes in the CTCF and cohesinSA-1 interactomes during erythropoiesis, chromatin immunoprecipitation coupled with high throughput sequencing and mRNA transcriptome analyses via RNA-seq were performed in primary human hematopoietic stem and progenitor cells (HSPC and primary human erythroid cells from single donors.Sites of CTCF and cohesinSA-1 co-occupancy were enriched in gene promoters in HSPC and erythroid cells compared to single CTCF or cohesin sites. Cell type-specific CTCF sites in erythroid cells were linked to highly expressed genes, with the opposite pattern observed in HSPCs. Chromatin domains were identified by ChIP-seq with antibodies against trimethylated lysine 27 histone H3, a modification associated with repressive chromatin. Repressive chromatin domains increased in both number and size during hematopoiesis, with many more repressive domains in erythroid cells than HSPCs. CTCF and cohesinSA-1 marked the boundaries of these repressive chromatin domains in a cell-type specific manner.These genome wide data, changes in sites of protein occupancy, chromatin architecture, and related gene expression, support the hypothesis that CTCF and cohesinSA-1 have multiple roles in the regulation of gene expression during erythropoiesis including transcriptional regulation at gene promoters and maintenance of chromatin architecture. These data from primary human erythroid cells provide a resource for studies of normal and perturbed erythropoiesis.

Effects of radiation and porphyrin on mitosis and chromosomes in human hematopoietic cell lines

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Tan, J.C.; Huang, C.C.; Fiel, R.J.

1976-01-01

The effect on mitosis of a human hematopoietic cell line RPMI-1788 treated with a metal chelate (Zn ++ ) of meso-tetra (p-carboxyphenyl) porphine (Zn-TCPP) alone at various concentrations or in combination with gamma-irradiation at various doses were studied. The results showed that both Zn-TCPP and radiation were effective in interfering with normal mitosis and that the effect of radiation was relatively more effective. Data also suggest interacting effects between Zn-TCPP and gamma-irradiation. At low doses of radiation, Zn-TCPP potentiated the effect of radiation. The reverse seemed to be true at a high dose of radiation. The effects of two porphyrins (Zn-TCPP and hematoporphyrin) and radiation on chromosomes were also studied. Chromosomal aberrations characteristic of radiation were observed. The porphyrins were found not to be effective chromosome-breaking agents under the experimental conditions tested

Prospectively Isolated Human Bone Marrow Cell-Derived MSCs Support Primitive Human CD34-Negative Hematopoietic Stem Cells.

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Matsuoka, Yoshikazu; Nakatsuka, Ryusuke; Sumide, Keisuke; Kawamura, Hiroshi; Takahashi, Masaya; Fujioka, Tatsuya; Uemura, Yasushi; Asano, Hiroaki; Sasaki, Yutaka; Inoue, Masami; Ogawa, Hiroyasu; Takahashi, Takayuki; Hino, Masayuki; Sonoda, Yoshiaki

2015-05-01

Hematopoietic stem cells (HSCs) are maintained in a specialized bone marrow (BM) niche, which consists of osteoblasts, endothelial cells, and a variety of mesenchymal stem/stromal cells (MSCs). However, precisely what types of MSCs support human HSCs in the BM remain to be elucidated because of their heterogeneity. In this study, we succeeded in prospectively isolating/establishing three types of MSCs from human BM-derived lineage- and CD45-negative cells, according to their cell surface expression of CD271 and stage-specific embryonic antigen (SSEA)-4. Among them, the MSCs established from the Lineage(-) CD45(-) CD271(+) SSEA-4(+) fraction (DP MSC) could differentiate into osteoblasts and chondrocytes, but they lacked adipogenic differentiation potential. The DP MSCs expressed significantly higher levels of well-characterized HSC-supportive genes, including IGF-2, Wnt3a, Jagged1, TGFβ3, nestin, CXCL12, and Foxc1, compared with other MSCs. Interestingly, these osteo-chondrogenic DP MSCs possessed the ability to support cord blood-derived primitive human CD34-negative severe combined immunodeficiency-repopulating cells. The HSC-supportive actions of DP MSCs were partially carried out by soluble factors, including IGF-2, Wnt3a, and Jagged1. Moreover, contact between DP MSCs and CD34-positive (CD34(+) ) as well as CD34-negative (CD34(-) ) HSCs was important for the support/maintenance of the CD34(+/-) HSCs in vitro. These data suggest that DP MSCs might play an important role in the maintenance of human primitive HSCs in the BM niche. Therefore, the establishment of DP MSCs provides a new tool for the elucidation of the human HSC/niche interaction in vitro as well as in vivo. © 2014 AlphaMed Press.

Clonal evolution of pre-leukemic hematopoietic stem cells precedes human acute myeloid leukemia.

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Majeti, Ravindra

2014-01-01

Massively parallel DNA sequencing has uncovered recurrent mutations in many human cancers. In acute myeloid leukemia (AML), cancer genome/exome resequencing has identified numerous recurrently mutated genes with an average of 5 mutations in each case of de novo AML. In order for these multiple mutations to accumulate in a single lineage of cells, they are serially acquired in clones of self-renewing hematopoietic stem cells (HSC), termed pre-leukemic HSC. Isolation and characterization of pre-leukemic HSC have shown that their mutations are enriched in genes involved in regulating DNA methylation, chromatin modifications, and the cohesin complex. On the other hand, genes involved in regulating activated signaling are generally absent. Pre-leukemic HSC have been found to persist in clinical remission and may ultimately give rise to relapsed disease through the acquisition of novel mutations. Thus, pre-leukemic HSC may constitute a key cellular reservoir that must be eradicated for long-term cures. Copyright © 2014 Elsevier Ltd. All rights reserved.

Long-Term Engraftment of Primary Bone Marrow Stromal Cells Repairs Niche Damage and Improves Hematopoietic Stem Cell Transplantation.

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Abbuehl, Jean-Paul; Tatarova, Zuzana; Held, Werner; Huelsken, Joerg

2017-08-03

Hematopoietic stem cell (HSC) transplantation represents a curative treatment for various hematological disorders. However, delayed reconstitution of innate and adaptive immunity often causes fatal complications. HSC maintenance and lineage differentiation are supported by stromal niches, and we now find that bone marrow stroma cells (BMSCs) are severely and permanently damaged by the pre-conditioning irradiation required for efficient HSC transplantation. Using mouse models, we show that stromal insufficiency limits the number of donor-derived HSCs and B lymphopoiesis. Intra-bone transplantation of primary, but not cultured, BMSCs quantitatively reconstitutes stroma function in vivo, which is mediated by a multipotent NT5E + (CD73) + ENG - (CD105) - LY6A + (SCA1) + BMSC subpopulation. BMSC co-transplantation doubles the number of functional, donor-derived HSCs and significantly reduces clinically relevant side effects associated with HSC transplantation including neutropenia and humoral immunodeficiency. These data demonstrate the potential of stroma recovery to improve HSC transplantation. Copyright © 2017 Elsevier Inc. All rights reserved.

CD146 expression on primary nonhematopoietic bone marrow stem cells is correlated with in situ localization

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Tormin, Ariane; Li, Ou; Brune, Jan Claas; Walsh, Stuart; Schütz, Birgit; Ehinger, Mats; Ditzel, Nicholas; Kassem, Moustapha

2011-01-01

Nonhematopoietic bone marrow mesenchymal stem cells (BM-MSCs) are of central importance for bone marrow stroma and the hematopoietic environment. However, the exact phenotype and anatomical distribution of specified MSC populations in the marrow are unknown. We characterized the phenotype of primary human BM-MSCs and found that all assayable colony-forming units-fibroblast (CFU-Fs) were highly and exclusively enriched not only in the lin−/CD271+/CD45−/CD146+ stem-cell fraction, but also in lin−/CD271+/CD45−/CD146−/low cells. Both populations, regardless of CD146 expression, shared a similar phenotype and genotype, gave rise to typical cultured stromal cells, and formed bone and hematopoietic stroma in vivo. Interestingly, CD146 was up-regulated in normoxia and down-regulated in hypoxia. This was correlated with in situ localization differences, with CD146 coexpressing reticular cells located in perivascular regions, whereas bone-lining MSCs expressed CD271 alone. In both regions, CD34+ hematopoietic stem/progenitor cells were located in close proximity to MSCs. These novel findings show that the expression of CD146 differentiates between perivascular versus endosteal localization of non-hematopoietic BM-MSC populations, which may be useful for the study of the hematopoietic environment. PMID:21415267

Evaluation of hematopoietic potential generated by transplantation of muscle-derived stem cells in mice.

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Farace, Francoise; Prestoz, Laetitita; Badaoui, Sabrina; Guillier, Martine; Haond, Celine; Opolon, Paule; Thomas, Jean-Leon; Zalc, Bernard; Vainchenker, William; Turhan, Ali G

2004-02-01

Muscle tissue of adult mice has been shown to contain stem cells with hematopoietic repopulation ability in vivo. To determine the functional characteristics of stem cells giving rise to this hematopoietic activity, we have performed hematopoietic reconstitution experiments by the use of muscle versus marrow transplantation in lethally irradiated mice and followed the fate of transplanted cells by Y-chimerism using PCR and fluorescence in situ hybridization (FISH) analysis. We report here that transplantation of murine muscle generate a major hematopoietic chimerism at the level of CFU-C, CFU-S, and terminally-differentiated cells in three generations of lethally irradiated mice followed up to 1 year after transplantation. This potential is totally abolished when muscle grafts were performed by the use of muscle from previously irradiated mice. As compared to marrow transplantation, muscle transplants were able to generate similar potencies to give rise to myeloid, T, B, and natural killer (NK) cells. Interestingly, marrow stem cells that have been generated in primary and then in secondary recipients were able to contribute efficiently to myofibers in the muscle tissue of tertiary recipients. Altogether, our data demonstrate that muscle-derived stem cells present a major hematopoietic repopulating ability with evidence of self-replication in vivo. They are radiation-sensitive and similar to marrow-derived stem cells in terms of their ability to generate multilineage hematopoiesis. Finally, our data demonstrate that muscle-derived hematopoietic stem cells do not lose their ability to contribute to myofiber generation after at least two rounds of serial transplantation, suggesting a potential that is probably equivalent to that generated by marrow transplantation.

Synergistic actions of hematopoietic and mesenchymal stem/progenitor cells in vascularizing bioengineered tissues.

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Eduardo K Moioli

Full Text Available Poor angiogenesis is a major road block for tissue repair. The regeneration of virtually all tissues is limited by angiogenesis, given the diffusion of nutrients, oxygen, and waste products is limited to a few hundred micrometers. We postulated that co-transplantation of hematopoietic and mesenchymal stem/progenitor cells improves angiogenesis of tissue repair and hence the outcome of regeneration. In this study, we tested this hypothesis by using bone as a model whose regeneration is impaired unless it is vascularized. Hematopoietic stem/progenitor cells (HSCs and mesenchymal stem/progenitor cells (MSCs were isolated from each of three healthy human bone marrow samples and reconstituted in a porous scaffold. MSCs were seeded in micropores of 3D calcium phosphate (CP scaffolds, followed by infusion of gel-suspended CD34(+ hematopoietic cells. Co-transplantation of CD34(+ HSCs and CD34(- MSCs in microporous CP scaffolds subcutaneously in the dorsum of immunocompromised mice yielded vascularized tissue. The average vascular number of co-transplanted CD34(+ and MSC scaffolds was substantially greater than MSC transplantation alone. Human osteocalcin was expressed in the micropores of CP scaffolds and was significantly increased upon co-transplantation of MSCs and CD34(+ cells. Human nuclear staining revealed the engraftment of transplanted human cells in vascular endothelium upon co-transplantation of MSCs and CD34(+ cells. Based on additional in vitro results of endothelial differentiation of CD34(+ cells by vascular endothelial growth factor (VEGF, we adsorbed VEGF with co-transplanted CD34(+ and MSCs in the microporous CP scaffolds in vivo, and discovered that vascular number and diameter further increased, likely owing to the promotion of endothelial differentiation of CD34(+ cells by VEGF. Together, co-transplantation of hematopoietic and mesenchymal stem/progenitor cells may improve the regeneration of vascular dependent tissues such as bone

Wnt3a protein reduces growth factor-driven expansion of human hematopoietic stem and progenitor cells in serum-free cultures

NARCIS (Netherlands)

L.E. Duinhouwer (Lucia); N. Tüysüz (Nesrin); E.J. Rombouts (Elwin); M.N.D. Ter Borg (Mariëtte N. D.); E. Mastrobattista; J. Spanholtz (Jan); J.J. Cornelissen (Jan); D. ten Berge (Derk); E. Braakman (Eric)

2015-01-01

textabstractAbstract Ex vivo expansion of hematopoietic stem and progenitor cells (HSPC) is a promising approach to improve insufficient engraftment after umbilical cord blood stem cell transplantation (UCB-SCT). Although culturing HSPC with hematopoietic cytokines results in

Exogenous endothelial cells as accelerators of hematopoietic reconstitution

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Mizer J

2012-11-01

Full Text Available Abstract Despite the successes of recombinant hematopoietic-stimulatory factors at accelerating bone marrow reconstitution and shortening the neutropenic period post-transplantation, significant challenges remain such as cost, inability to reconstitute thrombocytic lineages, and lack of efficacy in conditions such as aplastic anemia. A possible means of accelerating hematopoietic reconstitution would be administration of cells capable of secreting hematopoietic growth factors. Advantages of this approach would include: a ability to regulate secretion of cytokines based on biological need; b long term, localized production of growth factors, alleviating need for systemic administration of factors that possess unintended adverse effects; and c potential to actively repair the hematopoietic stem cell niche. Here we overview the field of hematopoietic growth factors, discuss previous experiences with mesenchymal stem cells (MSC in accelerating hematopoiesis, and conclude by putting forth the rationale of utilizing exogenous endothelial cells as a novel cellular therapy for acceleration of hematopoietic recovery.

Hematopoietic Stem Cell Therapy as a Counter-Measure for Human Exploration of Deep Space

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Ohi, S.; Roach, A.-N.; Ramsahai, S.; Kim, B. C.; Fitzgerald, W.; Riley, D. A.; Gonda, S. R.

2004-01-01

Human exploration of deep space depends, in part, on our ability to counter severe/invasive disorders that astronauts experience in space environments. The known symptoms include hematological/cardiac abnormalities,bone and muscle losses, immunodeficiency, neurological disorders, and cancer. Exploiting the extraordinary plasticity of hematopoietic stem cells (HSCs), which differentiate not only to all types of blood cells, but also to various tissues, we have advanced a hypothesis that ome of the space-caused disorders maybe amenable to hematopoietis stem cell therapy(HSCT) so as to maintain promote human exploration of deep space. Using mouse models of human anemia beta-thaiassemia) as well as spaceflight (hindlimb unloading system), we have obtained feasibility results of HSCT for space anemia, muscle loss, and immunodeficiency. For example, in the case of HSCT for muscle loss, the beta-galactosidese marked HSCs were detected in the hindlimbs of unloaded mouse following transplantation by -X-gal wholemaunt staining procedure. Histochemicaland physical analyses indicated structural contribution of HSCs to the muscle. HSCT for immunodeficiency was investigated ising beta-galactosidese gene-tagged Escherichia coli as the infectious agent. Results of the X-gal staining procedure indicated the rapeutic role of the HSCT. To facilitate the HSCT in space, growth of HSCs were optimized in the NASA Rotating Wall Vessel (RWV) culture systems, including Hydrodynamic Focusing Bioreactor (HFB).

Induction of multipotential hematopoietic progenitors from human pluripotent stem cells via re-specification of lineage-restricted precursors

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Doulatov, Sergei; Vo, Linda T.; Chou, Stephanie S.; Kim, Peter G.; Arora, Natasha; Li, Hu; Hadland, Brandon K.; Bernstein, Irwin D.; Collins, James J.; Zon, Leonard I.; Daley, George Q.

2013-01-01

Summary Human pluripotent stem cells (hPSCs) represent a promising source of patient-specific cells for disease modeling, drug screens, and cellular therapies. However, the inability to derive engraftable human hematopoietic stem and progenitor (HSPCs) has limited their characterization to in vitro assays. We report a strategy to re-specify lineage-restricted CD34+CD45+ myeloid precursors derived from hPSCs into multilineage progenitors that can be expanded in vitro and engraft in vivo. HOXA9, ERG, and RORA conferred self-renewal and multilineage potential in vitro and maintained primitive CD34+CD38− cells. Screening cells via transplantation revealed that two additional factors, SOX4 and MYB, were required for engraftment. Progenitors specified with all five factors gave rise to reproducible short-term engraftment with myeloid and erythroid lineages. Erythroid precursors underwent hemoglobin switching in vivo, silencing embryonic and activating adult globin expression. Our combinatorial screening approach establishes a strategy for obtaining transcription factor-mediated engraftment of blood progenitors from human pluripotent cells. PMID:24094326

CCND1-CDK4-mediated cell cycle progression provides a competitive advantage for human hematopoietic stem cells in vivo.

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Mende, Nicole; Kuchen, Erika E; Lesche, Mathias; Grinenko, Tatyana; Kokkaliaris, Konstantinos D; Hanenberg, Helmut; Lindemann, Dirk; Dahl, Andreas; Platz, Alexander; Höfer, Thomas; Calegari, Federico; Waskow, Claudia

2015-07-27

Maintenance of stem cell properties is associated with reduced proliferation. However, in mouse hematopoietic stem cells (HSCs), loss of quiescence results in a wide range of phenotypes, ranging from functional failure to extensive self-renewal. It remains unknown whether the function of human HSCs is controlled by the kinetics of cell cycle progression. Using human HSCs and human progenitor cells (HSPCs), we report here that elevated levels of CCND1-CDK4 complexes promoted the transit from G0 to G1 and shortened the G1 cell cycle phase, resulting in protection from differentiation-inducing signals in vitro and increasing human leukocyte engraftment in vivo. Further, CCND1-CDK4 overexpression conferred a competitive advantage without impacting HSPC numbers. In contrast, accelerated cell cycle progression mediated by elevated levels of CCNE1-CDK2 led to the loss of functional HSPCs in vivo. Collectively, these data suggest that the transition kinetics through the early cell cycle phases are key regulators of human HSPC function and important for lifelong hematopoiesis. © 2015 Mende et al.

Wnt3a protein reduces growth factor-driven expansion of human hematopoietic stem and progenitor cells in serum-free cultures

NARCIS (Netherlands)

Duinhouwer, Lucia E.; Tüysüz, Nesrin; Rombouts, Elwin W J C; Ter Borg, Mariette N D; Mastrobattista, Enrico; Spanholtz, Jan; Cornelissen, Jan J.; Berge, Derk Ten; Braakman, Eric

2015-01-01

Ex vivo expansion of hematopoietic stem and progenitor cells (HSPC) is a promising approach to improve insufficient engraftment after umbilical cord blood stem cell transplantation (UCB-SCT). Although culturing HSPC with hematopoietic cytokines results in robust proliferation, it is accompanied with

The hematopoietic chemokine CXCL12 promotes integration of human endothelial colony forming cell-derived cells into immature vessel networks.

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Newey, Sarah E; Tsaknakis, Grigorios; Khoo, Cheen P; Athanassopoulos, Thanassi; Camicia, Rosalba; Zhang, Youyi; Grabowska, Rita; Harris, Adrian L; Roubelakis, Maria G; Watt, Suzanne M

2014-11-15

Proangiogenic factors, vascular endothelial growth factor (VEGF), and fibroblast growth factor-2 (FGF-2) prime endothelial cells to respond to "hematopoietic" chemokines and cytokines by inducing/upregulating expression of the respective chemokine/cytokine receptors. Coculture of human endothelial colony forming cell (ECFC)-derived cells with human stromal cells in the presence of VEGF and FGF-2 for 14 days resulted in upregulation of the "hematopoietic" chemokine CXCL12 and its CXCR4 receptor by day 3 of coculture. Chronic exposure to the CXCR4 antagonist AMD3100 in this vasculo/angiogenesis assay significantly reduced vascular tubule formation, an observation recapitulated by delayed AMD3100 addition. While AMD3100 did not affect ECFC-derived cell proliferation, it did demonstrate a dual action. First, over the later stages of the 14-day cocultures, AMD3100 delayed tubule organization into maturing vessel networks, resulting in enhanced endothelial cell retraction and loss of complexity as defined by live cell imaging. Second, at earlier stages of cocultures, we observed that AMD3100 significantly inhibited the integration of exogenous ECFC-derived cells into established, but immature, vascular networks. Comparative proteome profiler array analyses of ECFC-derived cells treated with AMD3100 identified changes in expression of potential candidate molecules involved in adhesion and/or migration. Blocking antibodies to CD31, but not CD146 or CD166, reduced the ECFC-derived cell integration into these extant vascular networks. Thus, CXCL12 plays a key role not only in endothelial cell sensing and guidance, but also in promoting the integration of ECFC-derived cells into developing vascular networks.

Hematopoietic chimerism and transplantation tolerance: a role for regulatory T cells

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Lise ePasquet

2011-12-01

Full Text Available The major obstacle in transplantation medicine is rejection of donor tissues by the host’s immune system. Immunosuppressive drugs can delay but not prevent loss of transplants, and their efficiency is strongly impacted by inter-individual pharmacokinetic differences. Moreover, due to the global immunosuppression induced and to the broad distribution of their targets amongst human tissues, these drugs have severe side effects. Induction of donor-specific non-responsiveness (i.e. immunological tolerance to transplants would solve these problems and would substantially ameliorate patients’ quality of life. It is widely believed that bone marrow or hematopoietic stem cell transplantation, and resulting (mixed hematopoietic chimerism, invariably leads to immunological tolerance to organs of the same donor. A careful analysis of the literature, reviewed here, indeed shows that chimerism consistently prolongs allograft survival. However, in absence of additional conditioning leading to the development of active regulatory mechanisms, it does not prevent chronic rejection. A central role for active tolerance in transplantation-tolerance is also supported by recent data showing that genuine immunological tolerance to organ allografts can be achieved by combining induction of hematopoietic chimerism with infusion of regulatory T lymphocytes. Therefore, conditioning regimens that lead to the establishment of hematopoietic chimerism plus active regulatory mechanisms appear required for induction of genuine tolerance to allogeneic grafts.

Global patterns in human consumption of net primary production

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Imhoff, Marc L.; Bounoua, Lahouari; Ricketts, Taylor; Loucks, Colby; Harriss, Robert; Lawrence, William T.

2004-06-01

The human population and its consumption profoundly affect the Earth's ecosystems. A particularly compelling measure of humanity's cumulative impact is the fraction of the planet's net primary production that we appropriate for our own use. Net primary production-the net amount of solar energy converted to plant organic matter through photosynthesis-can be measured in units of elemental carbon and represents the primary food energy source for the world's ecosystems. Human appropriation of net primary production, apart from leaving less for other species to use, alters the composition of the atmosphere, levels of biodiversity, energy flows within food webs and the provision of important ecosystem services. Here we present a global map showing the amount of net primary production required by humans and compare it to the total amount generated on the landscape. We then derive a spatial balance sheet of net primary production `supply' and `demand' for the world. We show that human appropriation of net primary production varies spatially from almost zero to many times the local primary production. These analyses reveal the uneven footprint of human consumption and related environmental impacts, indicate the degree to which human populations depend on net primary production `imports' and suggest policy options for slowing future growth of human appropriation of net primary production.

Low/Negative Expression of PDGFR-α Identifies the Candidate Primary Mesenchymal Stromal Cells in Adult Human Bone Marrow

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Hongzhe Li

2014-12-01

Full Text Available Human bone marrow (BM contains a rare population of nonhematopoietic mesenchymal stromal cells (MSCs, which are of central importance for the hematopoietic microenvironment. However, the precise phenotypic definition of these cells in adult BM has not yet been reported. In this study, we show that low/negative expression of CD140a (PDGFR-α on lin−/CD45−/CD271+ BM cells identified a cell population with very high MSC activity, measured as fibroblastic colony-forming unit frequency and typical in vitro and in vivo stroma formation and differentiation capacities. Furthermore, these cells exhibited high levels of genes associated with mesenchymal lineages and HSC supportive function. Moreover, lin−/CD45−/CD271+/CD140alow/− cells effectively mediated the ex vivo expansion of transplantable CD34+ hematopoietic stem cells. Taken together, these data indicate that CD140a is a key negative selection marker for adult human BM-MSCs, which enables to prospectively isolate a close to pure population of candidate human adult stroma stem/progenitor cells with potent hematopoiesis-supporting capacity.

Haemopedia: An Expression Atlas of Murine Hematopoietic Cells

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Carolyn A. de Graaf

2016-09-01

Full Text Available Hematopoiesis is a multistage process involving the differentiation of stem and progenitor cells into distinct mature cell lineages. Here we present Haemopedia, an atlas of murine gene-expression data containing 54 hematopoietic cell types, covering all the mature lineages in hematopoiesis. We include rare cell populations such as eosinophils, mast cells, basophils, and megakaryocytes, and a broad collection of progenitor and stem cells. We show that lineage branching and maturation during hematopoiesis can be reconstructed using the expression patterns of small sets of genes. We also have identified genes with enriched expression in each of the mature blood cell lineages, many of which show conserved lineage-enriched expression in human hematopoiesis. We have created an online web portal called Haemosphere to make analyses of Haemopedia and other blood cell transcriptional datasets easier. This resource provides simple tools to interrogate gene-expression-based relationships between hematopoietic cell types and genes of interest.

Pre-malignant lymphoid cells arise from hematopoietic stem/progenitor cells in chronic lymphocytic leukemia.

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Kikushige, Yoshikane; Miyamoto, Toshihiro

2015-11-01

Human malignancies progress through a multistep process that includes the development of critical somatic mutations over the clinical course. Recent novel findings have indicated that hematopoietic stem cells (HSCs), which have the potential to self-renew and differentiate into multilineage hematopoietic cells, are an important cellular target for the accumulation of critical somatic mutations in hematological malignancies and play a central role in myeloid malignancy development. In contrast to myeloid malignancies, mature lymphoid malignancies, such as chronic lymphocytic leukemia (CLL), are thought to originate directly from differentiated mature lymphocytes; however, recent compelling data have shown that primitive HSCs and hematopoietic progenitor cells contribute to the pathogenesis of mature lymphoid malignancies. Several representative mutations of hematological malignancies have been identified within the HSCs of CLL and lymphoma patients, indicating that the self-renewing long-lived fraction of HSCs can serve as a reservoir for the development of oncogenic events. Novel mice models have been established as human mature lymphoma models, in which specific oncogenic events target the HSCs and immature progenitor cells. These data collectively suggest that HSCs can be the cellular target involved in the accumulation of oncogenic events in the pathogenesis of mature lymphoid and myeloid malignancies.

Expansion of donor-reactive host T cells in primary graft failure after allogeneic hematopoietic SCT following reduced-intensity conditioning.

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Koyama, M; Hashimoto, D; Nagafuji, K; Eto, T; Ohno, Y; Aoyama, K; Iwasaki, H; Miyamoto, T; Hill, G R; Akashi, K; Teshima, T

2014-01-01

Graft rejection remains a major obstacle in allogeneic hematopoietic SCT following reduced-intensity conditioning (RIC-SCT), particularly after cord blood transplantation (CBT). In a murine MHC-mismatched model of RIC-SCT, primary graft rejection was associated with activation and expansion of donor-reactive host T cells in peripheral blood and BM early after SCT. Donor-derived dendritic cells are at least partly involved in host T-cell activation. We then evaluated if such an expansion of host T cells could be associated with graft rejection after RIC-CBT. Expansion of residual host lymphocytes was observed in 4/7 patients with graft rejection at 3 weeks after CBT, but in none of the 17 patients who achieved engraftment. These results suggest the crucial role of residual host T cells after RIC-SCT in graft rejection and expansion of host T cells could be a marker of graft rejection. Development of more efficient T cell-suppressive conditioning regimens may be necessary in the context of RIC-SCT.

Identification of a population of cells with hematopoietic stem cell properties in mouse aorta-gonad-mesonephros cultures

International Nuclear Information System (INIS)

Nobuhisa, Ikuo; Ohtsu, Naoki; Okada, Seiji; Nakagata, Naomi; Taga, Tetsuya

2007-01-01

The aorta-gonad-mesonephros (AGM) region is a primary source of definitive hematopoietic cells in the midgestation mouse embryo. In cultures of dispersed AGM regions, adherent cells containing endothelial cells are observed first, and then non-adherent hematopoietic cells are produced. Here we report on the characterization of hematopoietic cells that emerge in the AGM culture. Based on the expression profiles of CD45 and c-Kit, we defined three cell populations: CD45 low c-Kit + cells that had the ability to form hematopoietic cell colonies in methylcellulose media and in co-cultures with stromal cells; CD45 low c-Kit - cells that showed a granulocyte morphology; CD45 high c-Kit low/- that exhibited a macrophage morphology. In co-cultures of OP9 stromal cells and freshly prepared AGM cultures, CD45 low c-Kit + cells from the AGM culture had the abilities to reproduce CD45 low c-Kit + cells and differentiate into CD45 low c-Kit - and CD45 high c-Kit low/- cells, whereas CD45 low c-Kit - and CD45 high c-Kit low/- did not produce CD45 low c-Kit + cells. Furthermore, CD45 low c-Kit + cells displayed a long-term repopulating activity in adult hematopoietic tissue when transplanted into the liver of irradiated newborn mice. These results indicate that CD45 low c-Kit + cells from the AGM culture have the potential to reconstitute multi-lineage hematopoietic cells

Restricted intra-embryonic origin of bona fide hematopoietic stem cells in the chicken

NARCIS (Netherlands)

Yvernogeau, Laurent; Robin, Catherine

2017-01-01

Hematopoietic stem cells (HSCs), which are responsible for blood cell production, are generated during embryonic development. Human and chicken embryos share features that position the chicken as a reliable and accessible alternative model to study developmental hematopoiesis. However, the existence

PRC2 inhibition counteracts the culture-associated loss of engraftment potential of human cord blood-derived hematopoietic stem and progenitor cells.

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Varagnolo, Linda; Lin, Qiong; Obier, Nadine; Plass, Christoph; Dietl, Johannes; Zenke, Martin; Claus, Rainer; Müller, Albrecht M

2015-07-22

Cord blood hematopoietic stem cells (CB-HSCs) are an outstanding source for transplantation approaches. However, the amount of cells per donor is limited and culture expansion of CB-HSCs is accompanied by a loss of engraftment potential. In order to analyze the molecular mechanisms leading to this impaired potential we profiled global and local epigenotypes during the expansion of human CB hematopoietic stem and progenitor cells (HPSCs). Human CB-derived CD34+ cells were cultured in serum-free medium together with SCF, TPO, FGF, with or without Igfbp2 and Angptl5 (STF/STFIA cocktails). As compared to the STF cocktail, the STFIA cocktail maintains in vivo repopulation capacity of cultured CD34+ cells. Upon expansion, CD34+ cells genome-wide remodel their epigenotype and depending on the cytokine cocktail, cells show different H3K4me3 and H3K27me3 levels. Expanding cells without Igfbp2 and Angptl5 leads to higher global H3K27me3 levels. ChIPseq analyses reveal a cytokine cocktail-dependent redistribution of H3K27me3 profiles. Inhibition of the PRC2 component EZH2 counteracts the culture-associated loss of NOD scid gamma (NSG) engraftment potential. Collectively, our data reveal chromatin dynamics that underlie the culture-associated loss of engraftment potential. We identify PRC2 component EZH2 as being involved in the loss of engraftment potential during the in vitro expansion of HPSCs.

CD133-targeted Gene Transfer Into Long-term Repopulating Hematopoietic Stem Cells

NARCIS (Netherlands)

Brendel, Christian; Goebel, Benjamin; Daniela, Abriss; Brugman, Martijn; Kneissl, Sabrina; Schwaeble, Joachim; Kaufmann, Kerstin B.; Mueller-Kuller, Uta; Kunkel, Hana; Chen-Wichmann, Linping; Abel, Tobias; Serve, Hubert; Bystrykh, Leonid; Buchholz, Christian J.; Grez, Manuel

Gene therapy for hematological disorders relies on the genetic modification of CD34(+) cells, a heterogeneous cell population containing about 0.01% long-term repopulating cells. Here, we show that the lentiviral vector CD133-LV, which uses a surface marker on human primitive hematopoietic stem

Oxymetholone Therapy of Fanconi Anemia Suppresses Osteopontin Transcription and Induces Hematopoietic Stem Cell Cycling

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Qing-Shuo Zhang

2015-01-01

Full Text Available Androgens are widely used for treating Fanconi anemia (FA and other human bone marrow failure syndromes, but their mode of action remains incompletely understood. Aged Fancd2−/− mice were used to assess the therapeutic efficacy of oxymetholone (OXM and its mechanism of action. Eighteen-month-old Fancd2−/− mice recapitulated key human FA phenotypes, including reduced bone marrow cellularity, red cell macrocytosis, and peripheral pancytopenia. As in humans, chronic OXM treatment significantly improved these hematological parameters and stimulated the proliferation of hematopoietic stem and progenitor cells. RNA-Seq analysis implicated downregulation of osteopontin as an important potential mechanism for the drug’s action. Consistent with the increased stem cell proliferation, competitive repopulation assays demonstrated that chronic OXM therapy eventually resulted in stem cell exhaustion. These results expand our knowledge of the regulation of hematopoietic stem cell proliferation and have direct clinical implications for the treatment of bone marrow failure.

Blood on the tracks: hematopoietic stem cell-endothelial cell interactions in homing and engraftment.

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Perlin, Julie R; Sporrij, Audrey; Zon, Leonard I

2017-08-01

Cells of the hematopoietic system undergo rapid turnover. Each day, humans require the production of about one hundred billion new blood cells for proper function. Hematopoietic stem cells (HSCs) are rare cells that reside in specialized niches and are required throughout life to produce specific progenitor cells that will replenish all blood lineages. There is, however, an incomplete understanding of the molecular and physical properties that regulate HSC migration, homing, engraftment, and maintenance in the niche. Endothelial cells (ECs) are intimately associated with HSCs throughout the life of the stem cell, from the specialized endothelial cells that give rise to HSCs, to the perivascular niche endothelial cells that regulate HSC homeostasis. Recent studies have dissected the unique molecular and physical properties of the endothelial cells in the HSC vascular niche and their role in HSC biology, which may be manipulated to enhance hematopoietic stem cell transplantation therapies.

Reduced hematopoietic stem cell frequency predicts outcome in acute myeloid leukemia

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Wang, Wenwen; Stiehl, Thomas; Raffel, Simon; Hoang, Van T.; Hoffmann, Isabel; Poisa-Beiro, Laura; Saeed, Borhan R.; Blume, Rachel; Manta, Linda; Eckstein, Volker; Bochtler, Tilmann; Wuchter, Patrick; Essers, Marieke; Jauch, Anna; Trumpp, Andreas; Marciniak-Czochra, Anna; Ho, Anthony D.; Lutz, Christoph

2017-01-01

In patients with acute myeloid leukemia and low percentages of aldehyde-dehydrogenase-positive cells, non-leukemic hematopoietic stem cells can be separated from leukemic cells. By relating hematopoietic stem cell frequencies to outcome we detected poor overall- and disease-free survival of patients with low hematopoietic stem cell frequencies. Serial analysis of matched diagnostic and follow-up samples further demonstrated that hematopoietic stem cells increased after chemotherapy in patients who achieved durable remissions. However, in patients who eventually relapsed, hematopoietic stem cell numbers decreased dramatically at the time of molecular relapse demonstrating that hematopoietic stem cell levels represent an indirect marker of minimal residual disease, which heralds leukemic relapse. Upon transplantation in immune-deficient mice cases with low percentages of hematopoietic stem cells of our cohort gave rise to leukemic or no engraftment, whereas cases with normal hematopoietic stem cell levels mostly resulted in multi-lineage engraftment. Based on our experimental data, we propose that leukemic stem cells have increased niche affinity in cases with low percentages of hematopoietic stem cells. To validate this hypothesis, we developed new mathematical models describing the dynamics of healthy and leukemic cells under different regulatory scenarios. These models suggest that the mechanism leading to decreases in hematopoietic stem cell frequencies before leukemic relapse must be based on expansion of leukemic stem cells with high niche affinity and the ability to dislodge hematopoietic stem cells. Thus, our data suggest that decreasing numbers of hematopoietic stem cells indicate leukemic stem cell persistence and the emergence of leukemic relapse. PMID:28550184

Reduced hematopoietic stem cell frequency predicts outcome in acute myeloid leukemia.

Science.gov (United States)

Wang, Wenwen; Stiehl, Thomas; Raffel, Simon; Hoang, Van T; Hoffmann, Isabel; Poisa-Beiro, Laura; Saeed, Borhan R; Blume, Rachel; Manta, Linda; Eckstein, Volker; Bochtler, Tilmann; Wuchter, Patrick; Essers, Marieke; Jauch, Anna; Trumpp, Andreas; Marciniak-Czochra, Anna; Ho, Anthony D; Lutz, Christoph

2017-09-01

In patients with acute myeloid leukemia and low percentages of aldehyde-dehydrogenase-positive cells, non-leukemic hematopoietic stem cells can be separated from leukemic cells. By relating hematopoietic stem cell frequencies to outcome we detected poor overall- and disease-free survival of patients with low hematopoietic stem cell frequencies. Serial analysis of matched diagnostic and follow-up samples further demonstrated that hematopoietic stem cells increased after chemotherapy in patients who achieved durable remissions. However, in patients who eventually relapsed, hematopoietic stem cell numbers decreased dramatically at the time of molecular relapse demonstrating that hematopoietic stem cell levels represent an indirect marker of minimal residual disease, which heralds leukemic relapse. Upon transplantation in immune-deficient mice cases with low percentages of hematopoietic stem cells of our cohort gave rise to leukemic or no engraftment, whereas cases with normal hematopoietic stem cell levels mostly resulted in multi-lineage engraftment. Based on our experimental data, we propose that leukemic stem cells have increased niche affinity in cases with low percentages of hematopoietic stem cells. To validate this hypothesis, we developed new mathematical models describing the dynamics of healthy and leukemic cells under different regulatory scenarios. These models suggest that the mechanism leading to decreases in hematopoietic stem cell frequencies before leukemic relapse must be based on expansion of leukemic stem cells with high niche affinity and the ability to dislodge hematopoietic stem cells. Thus, our data suggest that decreasing numbers of hematopoietic stem cells indicate leukemic stem cell persistence and the emergence of leukemic relapse. Copyright© 2017 Ferrata Storti Foundation.

Hematopoietic stem cell expansion : challenges and opportunities

NARCIS (Netherlands)

Walasek, Marta A.; van Os, Ronald; de Haan, Gerald; Kanz, L; Fibbe, WE; Lengerke, C; Dick, JE

2012-01-01

Attempts to improve hematopoietic reconstitution and engraftment potential of ex vivo-expanded hematopoietic stem and progenitor cells (HSPCs) have been largely unsuccessful due to the inability to generate sufficient stem cell numbers and to excessive differentiation of the starting cell

Precise chronology of differentiation of developing human primary dentition.

Science.gov (United States)

Hu, Xuefeng; Xu, Shan; Lin, Chensheng; Zhang, Lishan; Chen, YiPing; Zhang, Yanding

2014-02-01

While correlation of developmental stage with embryonic age of the human primary dentition has been well documented, the available information regarding the differentiation timing of the primary teeth was largely based on the observation of initial mineralization and varies significantly. In this study, we aimed to document precise differentiation timing of the developing human primary dentition. We systematically examined the expression of odontogenic differentiation markers along with the formation of mineralized tissue in each developing maxillary and mandibular teeth from human embryos with well-defined embryonic age. We show that, despite that all primary teeth initiate development at the same time, odontogenic differentiation begins in the maxillary incisors at the 15th week and in the mandibular incisors at the 16th week of gestation, followed by the canine, the first primary premolar, and the second primary premolar at a week interval sequentially. Despite that the mandibular primary incisors erupt earlier than the maxillary incisors, this distal to proximal sequential differentiation of the human primary dentition coincides in general with the sequence of tooth eruption. Our results provide an accurate chronology of odontogenic differentiation of the developing human primary dentition, which could be used as reference for future studies of human tooth development.

TLR-mediated albuminuria needs TNFα-mediated cooperativity between TLRs present in hematopoietic tissues and CD80 present on non-hematopoietic tissues in mice

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Nidhi Jain

2016-06-01

Full Text Available Transient albuminuria induced by pathogen-associated molecular patterns (PAMPs in mice through engagement of Toll-like receptors (TLRs is widely studied as a partial model for some forms of human nephrotic syndrome (NS. In addition to TLRs, CD80 has been shown to be essential for PAMP-mediated albuminuria. However, the mechanistic relationships between TLRs, CD80 and albuminuria remain unclear. Here, we show that albuminuria and CD80-uria induced in mice by many TLR ligands are dependent on the expression of TLRs and their downstream signalling intermediate MyD88 exclusively in hematopoietic cells and, conversely, on CD80 expression exclusively in non-hematopoietic cells. TNFα is crucial for TLR-mediated albuminuria and CD80-uria, and induces CD80 expression in cultured renal podocytes. IL-10 from hematopoietic cells ameliorates TNFα production, albuminuria and CD80-uria but does not prevent TNFα-mediated induction of podocyte CD80 expression. Chitohexaose, a small molecule originally of parasite origin, mediates TLR4-dependent anti-inflammatory responses, and blocks TLR-mediated albuminuria and CD80-uria through IL-10. Thus, TNFα is a prominent mediator of renal CD80 induction and resultant albuminuria in this model, and small molecules modulating TLR-mediated inflammatory activation might have contributory or adjunct therapeutic potential in some contexts of NS development.

Importance of killer immunoglobulin-like receptors in allogeneic hematopoietic stem cell transplantation

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Danilo Santana Alessio Franceschi

2011-01-01

Full Text Available Hematopoietic stem cell transplantation is the treatment of choice for many hematologic diseases, such as multiple myeloma, bone marrow aplasia and leukemia. Human leukocyte antigen (HLA compatibility is an important tool to prevent post-transplant complications such as graft rejection and graft-versus-host disease, but the high rates of relapse limit the survival of transplant patients. Natural Killer cells, a type of lymphocyte that is a key element in the defense against tumor cells, cells infected with viruses and intracellular microbes, have different receptors on their surfaces that regulate their cytotoxicity. Killer immunoglobulin-like receptors are the most important, interacting consistently with human leukocyte antigen class I molecules present in other cells and thus controlling the activation of natural killer cells. Several studies have shown that certain combinations of killer immunoglobulin-like receptors and human leukocyte antigens (in both donors and recipients can affect the chances of survival of transplant patients, particularly in relation to the graft-versusleukemia effect, which may be associated to decreased relapse rates in certain groups. This review aims to shed light on the mechanisms and effects of killer immunoglobulin-like receptors - human leukocyte antigen associations and their implications following hematopoietic stem cell transplantation, and to critically analyze the results obtained by the studies presented herein.

Histone deacetylase inhibition regulates inflammation and enhances Tregs after allogeneic hematopoietic cell transplantation in humans

NARCIS (Netherlands)

Choi, S.W.; Gatza, E.; Hou, G.; Sun, Y; Whitfield, J.; Song, Y.; Oravecz-Wilson, K.; Tawara, I.; Dinarello, C.A.; Reddy, P.

2015-01-01

We examined immunological responses in patients receiving histone deacetylase (HDAC) inhibition (vorinostat) for graft-versus-host disease prophylaxis after allogeneic hematopoietic cell transplant. Vorinostat treatment increased histone acetylation in peripheral blood mononuclear cells (PBMCs) from

Biology and flow cytometry of proangiogenic hematopoietic progenitors cells.

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Rose, Jonathan A; Erzurum, Serpil; Asosingh, Kewal

2015-01-01

During development, hematopoiesis and neovascularization are closely linked to each other via a common bipotent stem cell called the hemangioblast that gives rise to both hematopoietic cells and endothelial cells. In postnatal life, this functional connection between the vasculature and hematopoiesis is maintained by a subset of hematopoietic progenitor cells endowed with the capacity to differentiate into potent proangiogenic cells. These proangiogenic hematopoietic progenitors comprise a specific subset of bone marrow (BM)-derived cells that homes to sites of neovascularization and possess potent paracrine angiogenic activity. There is emerging evidence that this subpopulation of hematopoietic progenitors plays a critical role in vascular health and disease. Their angiogenic activity is distinct from putative "endothelial progenitor cells" that become structural cells of the endothelium by differentiation into endothelial cells. Proangiogenic hematopoietic progenitor cell research requires multidisciplinary expertise in flow cytometry, hematology, and vascular biology. This review provides a comprehensive overview of proangiogenic hematopoietic progenitor cell biology and flow cytometric methods to detect these cells in the peripheral blood circulation and BM. © 2014 International Society for Advancement of Cytometry.

Vascular niche promotes hematopoietic multipotent progenitor formation from pluripotent stem cells

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Gori, Jennifer L.; Butler, Jason M.; Chan, Yan-Yi; Chandrasekaran, Devikha; Poulos, Michael G.; Ginsberg, Michael; Nolan, Daniel J.; Elemento, Olivier; Wood, Brent L.; Adair, Jennifer E.; Rafii, Shahin; Kiem, Hans-Peter

2015-01-01

Pluripotent stem cells (PSCs) represent an alternative hematopoietic stem cell (HSC) source for treating hematopoietic disease. The limited engraftment of human PSC–derived (hPSC-derived) multipotent progenitor cells (MPP) has hampered the clinical application of these cells and suggests that MPP require additional cues for definitive hematopoiesis. We hypothesized that the presence of a vascular niche that produces Notch ligands jagged-1 (JAG1) and delta-like ligand-4 (DLL4) drives definitive hematopoiesis. We differentiated hes2 human embryonic stem cells (hESC) and Macaca nemestrina–induced PSC (iPSC) line-7 with cytokines in the presence or absence of endothelial cells (ECs) that express JAG1 and DLL4. Cells cocultured with ECs generated substantially more CD34+CD45+ hematopoietic progenitors compared with cells cocultured without ECs or with ECs lacking JAG1 or DLL4. EC-induced cells exhibited Notch activation and expressed HSC-specific Notch targets RUNX1 and GATA2. EC-induced PSC-MPP engrafted at a markedly higher level in NOD/SCID/IL-2 receptor γ chain–null (NSG) mice compared with cytokine-induced cells, and low-dose chemotherapy-based selection further increased engraftment. Long-term engraftment and the myeloid-to-lymphoid ratio achieved with vascular niche induction were similar to levels achieved for cord blood–derived MPP and up to 20-fold higher than those achieved with hPSC-derived MPP engraftment. Our findings indicate that endothelial Notch ligands promote PSC-definitive hematopoiesis and production of long-term engrafting CD34+ cells, suggesting these ligands are critical for HSC emergence. PMID:25664855

Comparison of hybrid capture and reverse transcriptase polymerase chain reaction methods in terms of diagnosing human cytomegalovirus infection in patients following hematopoietic stem cell transplantation

International Nuclear Information System (INIS)

Orsal, Arif S.; Ozsan, M.; Dolapci, I.; Tekeli, A.; Becksac, M.

2006-01-01

Human cytomegalovirus (CMV) is a life threatening cause of infection among hematopoietic stem cell recipients. Developing reliable methods in detecting the CMV infection is important to identify the patients at risk of CMV infection and disease. The aim of this study was to compare the 2 tests- hybrid capture test, which is routinely used in the diagnosis of CMV infection among hematopoietic stem cell recipients, and reverse transcriptase polymerase chain reaction (RT-PCR) detecting UL21.5 mRNA transcripts of the active virus. In this prospective study, a total of 178 blood samples obtained 35 patients following allogeneic hematopoietic stem cell transplantation at the Bone Marrow Transplantation Unit of the Hematology Department, Ibn-i-Sina Hospital of Ankara University School of Medicine, Turkey between January 2003 and September 2003 were analyzed. Hybrid capture and RT-PCR using UL21.5 gene transcript method to investigate HCMV in blood samples were performed at the department of Microbiology and Clinic Microbiology, Ankara University School of Medicine, Turkey. When Hybrid capture test was accepted as the golden standard, the sensitivity of Rt-PCR was 3%, specificity 100%, false negativity 67%, false positivity 0%, positive predictive value 100%, negative predictive value 74%, and accuracy was 77%. Improving this test by quantification, and application of additional gene transcripts, primarily the late gene transcripts can help increase the sensitivity and feasibility. (author)

The biochemistry of hematopoietic stem cell development

NARCIS (Netherlands)

P. Kaimakis (Polynikis); M. Crisan (Mihaela); E.A. Dzierzak (Elaine)

2013-01-01

textabstractBackground: The cornerstone of the adult hematopoietic system and clinical treatments for blood-related disease is the cohort of hematopoietic stem cells (HSC) that is harbored in the adult bone marrow microenvironment. Interestingly, this cohort of HSCs is generated only during a short

A small-molecule/cytokine combination enhances hematopoietic stem cell proliferation via inhibition of cell differentiation.

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Wang, Lan; Guan, Xin; Wang, Huihui; Shen, Bin; Zhang, Yu; Ren, Zhihua; Ma, Yupo; Ding, Xinxin; Jiang, Yongping

2017-07-18

Accumulated evidence supports the potent stimulating effects of multiple small molecules on the expansion of hematopoietic stem cells (HSCs) which are important for the therapy of various hematological disorders. Here, we report a novel, optimized formula, named the SC cocktail, which contains a combination of three such small molecules and four cytokines. Small-molecule candidates were individually screened and then combined at their optimal concentration with the presence of cytokines to achieve maximum capacity for stimulating the human CD34 + cell expansion ex vivo. The extent of cell expansion and the immunophenotype of expanded cells were assessed through flow cytometry. The functional preservation of HSC stemness was confirmed by additional cell and molecular assays in vitro. Subsequently, the expanded cells were transplanted into sublethally irradiated NOD/SCID mice for the assessment of human cell viability and engraftment potential in vivo. Furthermore, the expression of several genes in the cell proliferation and differentiation pathways was analyzed through quantitative polymerase chain reaction (qPCR) during the process of CD34 + cell expansion. The SC cocktail supported the retention of the immunophenotype of hematopoietic stem/progenitor cells remarkably well, by yielding purities of 86.6 ± 11.2% for CD34 + cells and 76.2 ± 10.5% for CD34 + CD38 - cells, respectively, for a 7-day culture. On day 7, the enhancement of expansion of CD34 + cells and CD34 + CD38 - cells reached a maxima of 28.0 ± 5.5-fold and 27.9 ± 4.3-fold, respectively. The SC cocktail-expanded CD34 + cells preserved the characteristics of HSCs by effectively inhibiting their differentiation in vitro and retained the multilineage differentiation potential in primary and secondary in vivo murine xenotransplantation trials. Further gene expression analysis suggested that the small-molecule combination strengthened the ability of the cytokines to enhance the Notch

Tritium contamination of hematopoietic stem cells alters long-term hematopoietic reconstitution

International Nuclear Information System (INIS)

Di Giacomo, F.; Barroca, V.; Laurent, D.; Lewandowski, D.; Saintigny, Y.; Romeo, P.H.; Granotier, Ch.; Boussin, F.D.

2011-01-01

Purpose: In vivo effects of tritium contamination are poorly documented. Here, we study the effects of tritiated Thymidine ([ 3 H] Thymidine) or tritiated water (HTO) contamination on the biological properties of hematopoietic stem cells (HSC). Materials and methods: Mouse HSC were contaminated with concentrations of [ 3 H] Thymidine ranging from 0.37-37.03 kBq/ml or of HTO ranging from 5-50 kBq/ml. The biological properties of contaminated HSC were studied in vitro after HTO contamination and in vitro and in vivo after [ 3 H] Thymidine contamination. Results: Proliferation, viability and double-strand breaks were dependent on [ 3 H] Thymidine or HTO concentrations used for contamination but in vitro myeloid differentiation of HSC was not affected by [ 3 H] Thymidine contamination. [ 3 H] Thymidine contaminated HSC showed a compromised long-term capacity of hematopoietic reconstitution and competition experiments showed an up to two-fold decreased capacity of contaminated HSC to reconstitute hematopoiesis. These defects were not due to impaired homing in bone marrow but to an initial decreased proliferation rate of HSC. Conclusion: These results indicate that contaminations of HSC with doses of tritium that do not result in cell death, induce short-term effects on proliferation and cell cycle and long-term effects on hematopoietic reconstitution capacity of contaminated HSC. (authors)

CCND1–CDK4–mediated cell cycle progression provides a competitive advantage for human hematopoietic stem cells in vivo

Science.gov (United States)

Mende, Nicole; Kuchen, Erika E.; Lesche, Mathias; Grinenko, Tatyana; Kokkaliaris, Konstantinos D.; Hanenberg, Helmut; Lindemann, Dirk; Dahl, Andreas; Platz, Alexander; Höfer, Thomas; Calegari, Federico

2015-01-01

Maintenance of stem cell properties is associated with reduced proliferation. However, in mouse hematopoietic stem cells (HSCs), loss of quiescence results in a wide range of phenotypes, ranging from functional failure to extensive self-renewal. It remains unknown whether the function of human HSCs is controlled by the kinetics of cell cycle progression. Using human HSCs and human progenitor cells (HSPCs), we report here that elevated levels of CCND1–CDK4 complexes promoted the transit from G0 to G1 and shortened the G1 cell cycle phase, resulting in protection from differentiation-inducing signals in vitro and increasing human leukocyte engraftment in vivo. Further, CCND1–CDK4 overexpression conferred a competitive advantage without impacting HSPC numbers. In contrast, accelerated cell cycle progression mediated by elevated levels of CCNE1–CDK2 led to the loss of functional HSPCs in vivo. Collectively, these data suggest that the transition kinetics through the early cell cycle phases are key regulators of human HSPC function and important for lifelong hematopoiesis. PMID:26150472

A distinct hematopoietic stem cell population for rapid multilineage engraftment in nonhuman primates.

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Radtke, Stefan; Adair, Jennifer E; Giese, Morgan A; Chan, Yan-Yi; Norgaard, Zachary K; Enstrom, Mark; Haworth, Kevin G; Schefter, Lauren E; Kiem, Hans-Peter

2017-11-01

Hematopoietic reconstitution after bone marrow transplantation is thought to be driven by committed multipotent progenitor cells followed by long-term engrafting hematopoietic stem cells (HSCs). We observed a population of early-engrafting cells displaying HSC-like behavior, which persisted long-term in vivo in an autologous myeloablative transplant model in nonhuman primates. To identify this population, we characterized the phenotype and function of defined nonhuman primate hematopoietic stem and progenitor cell (HSPC) subsets and compared these to human HSPCs. We demonstrated that the CD34 + CD45RA - CD90 + cell phenotype is highly enriched for HSCs. This population fully supported rapid short-term recovery and robust multilineage hematopoiesis in the nonhuman primate transplant model and quantitatively predicted transplant success and time to neutrophil and platelet recovery. Application of this cell population has potential in the setting of HSC transplantation and gene therapy/editing approaches. Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

Radioprotective effect of hematopoietic growth factor gene therapy regulated by Egr-1 promoter on radiation injury of SCID mice

International Nuclear Information System (INIS)

Du Nan; Pei Xuetao; Luo Chengji; Su Yongping; Cheng Tianmin

2002-01-01

Objective: To explore the radioprotective effect of the expression of hematopoietic growth factors regulated by radio-inducible promoter on radiation injury. Methods: The human FL cDNA and EGFP cDNA were linked together with an internal ribosome entry site (IRES) and then inserted into the eukaryotic expression vector pCI-neo with the Egr-1 promoter (Egr-EF), and further transduced into bone marrow stromal cell lines HFCL (HFCL/EF). The HFCL/EF and CD34 + cells from human umbilical cord blood were transplanted i.v. one after the other into sublethally irradiated severe combined immunodeficient (SCID) mice. The number of peripheral blood WBC and human cells engrafted in recipient mice were detected by flow cytometry and CFU-GM assay. Results: In contrast to two control groups (HFCL and HFCL/F), HFCL/EF (the Egr-1 regulatory element-driven expression of FL gene therapy) resulted in a proportionally obvious increase in the number of the WBC at early stage after irradiation. Significant differences were found for CD45 + , CD34 + , CFU-GM, and nucleated cells in the bone marrow. Conclusion: Hematopoietic growth factor gene therapy regulated by radio-inducible promoter has radioprotective effect on radiation hematopoietic injury

Genetic modification of bone-marrow mesenchymal stem cells and hematopoietic cells with human coagulation factor IX-expressing plasmids.

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Sam, Mohammad Reza; Azadbakhsh, Azadeh Sadat; Farokhi, Farrah; Rezazadeh, Kobra; Sam, Sohrab; Zomorodipour, Alireza; Haddad-Mashadrizeh, Aliakbar; Delirezh, Nowruz; Mokarizadeh, Aram

2016-05-01

Ex-vivo gene therapy of hemophilias requires suitable bioreactors for secretion of hFIX into the circulation and stem cells hold great potentials in this regard. Viral vectors are widely manipulated and used to transfer hFIX gene into stem cells. However, little attention has been paid to the manipulation of hFIX transgene itself. Concurrently, the efficacy of such a therapeutic approach depends on determination of which vectors give maximal transgene expression. With this in mind, TF-1 (primary hematopoietic lineage) and rat-bone marrow mesenchymal stem cells (BMSCs) were transfected with five hFIX-expressing plasmids containing different combinations of two human β-globin (hBG) introns inside the hFIX-cDNA and Kozak element and hFIX expression was evaluated by different methods. In BMSCs and TF-1 cells, the highest hFIX level was obtained from the intron-less and hBG intron-I,II containing plasmids respectively. The highest hFIX activity was obtained from the cells that carrying the hBG intron-I,II containing plasmids. BMSCs were able to produce higher hFIX by 1.4 to 4.7-fold increase with activity by 2.4 to 4.4-fold increase compared to TF-1 cells transfected with the same constructs. BMSCs and TF-1 cells could be effectively bioengineered without the use of viral vectors and hFIX minigene containing hBG introns could represent a particular interest in stem cell-based gene therapy of hemophilias. Copyright © 2016 International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.

Two Hemocyte Lineages Exist in Silkworm Larval Hematopoietic Organ

OpenAIRE

Nakahara, Yuichi; Kanamori, Yasushi; Kiuchi, Makoto; Kamimura, Manabu

2010-01-01

BACKGROUND: Insects have multiple hemocyte morphotypes with different functions as do vertebrates, however, their hematopoietic lineages are largely unexplored with the exception of Drosophila melanogaster. METHODOLOGY/PRINCIPAL FINDINGS: To study the hematopoietic lineage of the silkworm, Bombyx mori, we investigated in vivo and in vitro differentiation of hemocyte precursors in the hematopoietic organ (HPO) into the four mature hemocyte subsets, namely, plasmatocytes, granulocytes, oenocyto...

Long-term culture and differentiation of porcine red bone marrow hematopoietic cells co-cultured with immortalized mesenchymal cells.

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Garba, Abubakar; Acar, Delphine D; Roukaerts, Inge D M; Desmarets, Lowiese M B; Devriendt, Bert; Nauwynck, Hans J

2017-09-01

Mesenchymal cells are multipotent stromal cells with self-renewal, differentiation and immunomodulatory capabilities. We aimed to develop a co-culture model for differentiating hematopoietic cells on top of immortalized mesenchymal cells for studying interactions between hematopoietic and mesenchymal cells, useful for adequately exploring the therapeutic potential of mesenchymal cells. In this study, we investigated the survival, proliferation and differentiation of porcine red bone marrow hematopoietic cells co-cultured with immortalized porcine bone marrow mesenchymal cells for a period of five weeks. Directly after collection, primary porcine bone marrow mesenchymal cells adhered firmly to the bottom of the culture plates and showed a fibroblast-like appearance, one week after isolation. Upon immortalization, porcine bone marrow mesenchymal cells were continuously proliferating. They were positive for simian virus 40 (SV40) large T antigen and the mesenchymal cell markers CD44 and CD55. Isolated red bone marrow cells were added to these immortalized mesenchymal cells. Five weeks post-seeding, 92±6% of the red bone marrow hematopoietic cells were still alive and their number increased 3-fold during five weekly subpassages on top of the immortalized mesenchymal cells. The red bone marrow hematopoietic cells were originally small and round; later, the cells increased in size. Some of them became elongated, while others remained round. Tiny dendrites appeared attaching hematopoietic cells to the underlying immortalized mesenchymal cells. Furthermore, weekly differential-quick staining of the cells indicated the presence of monoblasts, monocytes, macrophages and lymphocytes in the co-cultures. At three weeks of co-culture, flow cytometry analysis showed an increased surface expression of CD172a, CD14, CD163, CD169, CD4 and CD8 up to 37±0.8%, 40±8%, 41±4%, 23±3% and 19±5% of the hematopoietic cells, respectively. In conclusion, continuous mesenchymal cell

CGRP in human models of primary headaches

DEFF Research Database (Denmark)

Ashina, Håkan; Schytz, Henrik Winther; Ashina, Messoud

2018-01-01

experiments are likely due to assay variation; therefore, proper validation and standardization of an assay is needed. To what extent CGRP is involved in tension-type headache and cluster headache is unknown. CONCLUSION: Human models of primary headaches have elucidated the role of CGRP in headache...... pathophysiology and sparked great interest in developing new treatment strategies using CGRP antagonists and antibodies. Future studies applying more refined human experimental models should identify biomarkers of CGRP-induced primary headache and reveal whether CGRP provocation experiments could be used......OBJECTIVE: To review the role of CGRP in human models of primary headaches and to discuss methodological aspects and future directions. DISCUSSION: Provocation experiments demonstrated a heterogeneous CGRP migraine response in migraine patients. Conflicting CGRP plasma results in the provocation...

Prolonged Shedding of Human Coronavirus in Hematopoietic Cell Transplant Recipients: Risk Factors and Viral Genome Evolution.

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Ogimi, Chikara; Greninger, Alexander L; Waghmare, Alpana A; Kuypers, Jane M; Shean, Ryan C; Xie, Hu; Leisenring, Wendy M; Stevens-Ayers, Terry L; Jerome, Keith R; Englund, Janet A; Boeckh, Michael

2017-07-15

Recent data suggest that human coronavirus (HCoV) pneumonia is associated with significant mortality in hematopoietic cell transplant (HCT) recipients. Investigation of risk factors for prolonged shedding and intrahost genome evolution may provide critical information for development of novel therapeutics. We retrospectively reviewed HCT recipients with HCoV detected in nasal samples by polymerase chain reaction (PCR). HCoV strains were identified using strain-specific PCR. Shedding duration was defined as time between first positive and first negative sample. Logistic regression analyses were performed to evaluate factors for prolonged shedding (≥21 days). Metagenomic next-generation sequencing (mNGS) was conducted when ≥4 samples with cycle threshold values of Genome changes were consistent with the expected molecular clock of HCoV. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

A case series of clinically undiagnosed hematopoietic neoplasms discovered at autopsy.

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Podduturi, Varsha; Guileyardo, Joseph M; Soto, Luis R; Krause, John R

2015-06-01

In the United States, autopsy rates have diminished to less than 5% during the last half of the 20th century and the beginning of the 21st century for a multitude of reasons. Many believe this results in unrecognized malignancies that could have explained a patient's death. We describe six deaths in which hematopoietic neoplasms were identified at autopsy but were not diagnosed clinically. The six undiagnosed hematopoietic malignancy cases discovered at autopsy include four men and two women ranging from 50 to 78 years of age. One patient was African American and five patients were white, all with multiple comorbidities. The tumors included diffuse large B-cell lymphoma, activated B-cell type, intravascular large B-cell lymphoma, ALK-negative anaplastic large cell lymphoma arising in a setting of human immunodeficiency virus, and a myeloid sarcoma. These cases illustrate the importance of the traditional postmortem examination in not only confirming clinical diagnoses but also identifying previously unknown diagnoses. Hematologic malignancies may present with nonspecific clinical manifestations, and this series of cases also emphasizes the necessity for widening the differential diagnosis in patients with unexplained lactic acidosis and hepatic failure to include hematopoietic malignancies since prompt treatment may be lifesaving. Copyright© by the American Society for Clinical Pathology.

Nuclear Factor Erythroid 2 Regulates Human HSC Self-Renewal and T Cell Differentiation by Preventing NOTCH1 Activation.

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Di Tullio, Alessandro; Passaro, Diana; Rouault-Pierre, Kevin; Purewal, Sukhveer; Bonnet, Dominique

2017-07-11

Nuclear factor erythroid-derived 2 (NF-E2) has been associated with megakaryocyte maturation and platelet production. Recently, an increased in NF-E2 activity has been implicated in myeloproliferative neoplasms. Here, we investigate the role of NF-E2 in normal human hematopoiesis. Knockdown of NF-E2 in the hematopoietic stem and progenitor cells (HSPCs) not only reduced the formation of megakaryocytes but also drastically impaired hematopoietic stem cell activity, decreasing human engraftment in immunodeficient (NSG) mice. This phenotype is likely to be related to both increased cell proliferation (p21-mediated) and reduced Notch1 protein expression, which favors HSPC differentiation over self-renewal. Strikingly, although NF-E2 silencing in HSPCs did not affect their myeloid and B cell differentiation in vivo, it almost abrogated T cell production in primary hosts, as confirmed by in vitro studies. This effect is at least partly due to Notch1 downregulation in NF-E2-silenced HSPCs. Together these data reveal that NF-E2 is an important driver of human hematopoietic stem cell maintenance and T lineage differentiation. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

Nuclear Factor Erythroid 2 Regulates Human HSC Self-Renewal and T Cell Differentiation by Preventing NOTCH1 Activation

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Alessandro Di Tullio

2017-07-01

Full Text Available Nuclear factor erythroid-derived 2 (NF-E2 has been associated with megakaryocyte maturation and platelet production. Recently, an increased in NF-E2 activity has been implicated in myeloproliferative neoplasms. Here, we investigate the role of NF-E2 in normal human hematopoiesis. Knockdown of NF-E2 in the hematopoietic stem and progenitor cells (HSPCs not only reduced the formation of megakaryocytes but also drastically impaired hematopoietic stem cell activity, decreasing human engraftment in immunodeficient (NSG mice. This phenotype is likely to be related to both increased cell proliferation (p21-mediated and reduced Notch1 protein expression, which favors HSPC differentiation over self-renewal. Strikingly, although NF-E2 silencing in HSPCs did not affect their myeloid and B cell differentiation in vivo, it almost abrogated T cell production in primary hosts, as confirmed by in vitro studies. This effect is at least partly due to Notch1 downregulation in NF-E2-silenced HSPCs. Together these data reveal that NF-E2 is an important driver of human hematopoietic stem cell maintenance and T lineage differentiation.

Hematopoietic stem cell cytokines and fibroblast growth factor-2 stimulate human endothelial cell-pericyte tube co-assembly in 3D fibrin matrices under serum-free defined conditions.

Directory of Open Access Journals (Sweden)

Annie O Smith

Full Text Available We describe a novel 3D fibrin matrix model using recombinant hematopoietic stem cell cytokines under serum-free defined conditions which promotes the assembly of human endothelial cell (EC tubes with co-associated pericytes. Individual ECs and pericytes are randomly mixed together and EC tubes form that is accompanied by pericyte recruitment to the EC tube abluminal surface over a 3-5 day period. These morphogenic processes are stimulated by a combination of the hematopoietic stem cell cytokines, stem cell factor, interleukin-3, stromal derived factor-1α, and Flt-3 ligand which are added in conjunction with fibroblast growth factor (FGF-2 into the fibrin matrix. In contrast, this tube morphogenic response does not occur under serum-free defined conditions when VEGF and FGF-2 are added together in the fibrin matrices. We recently demonstrated that VEGF and FGF-2 are able to prime EC tube morphogenic responses (i.e. added overnight prior to the morphogenic assay to hematopoietic stem cell cytokines in collagen matrices and, interestingly, they also prime EC tube morphogenesis in 3D fibrin matrices. EC-pericyte interactions in 3D fibrin matrices leads to marked vascular basement membrane assembly as demonstrated using immunofluorescence and transmission electron microscopy. Furthermore, we show that hematopoietic stem cell cytokines and pericytes stimulate EC sprouting in fibrin matrices in a manner dependent on the α5β1 integrin. This novel co-culture system, under serum-free defined conditions, allows for a molecular analysis of EC tube assembly, pericyte recruitment and maturation events in a critical ECM environment (i.e. fibrin matrices that regulates angiogenic events in postnatal life.

Whole-transcriptome analysis of endothelial to hematopoietic stem cell transition reveals a requirement for Gpr56 in HSC generation.

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Solaimani Kartalaei, Parham; Yamada-Inagawa, Tomoko; Vink, Chris S; de Pater, Emma; van der Linden, Reinier; Marks-Bluth, Jonathon; van der Sloot, Anthon; van den Hout, Mirjam; Yokomizo, Tomomasa; van Schaick-Solernó, M Lucila; Delwel, Ruud; Pimanda, John E; van IJcken, Wilfred F J; Dzierzak, Elaine

2015-01-12

Hematopoietic stem cells (HSCs) are generated via a natural transdifferentiation process known as endothelial to hematopoietic cell transition (EHT). Because of small numbers of embryonal arterial cells undergoing EHT and the paucity of markers to enrich for hemogenic endothelial cells (ECs [HECs]), the genetic program driving HSC emergence is largely unknown. Here, we use a highly sensitive RNAseq method to examine the whole transcriptome of small numbers of enriched aortic HSCs, HECs, and ECs. Gpr56, a G-coupled protein receptor, is one of the most highly up-regulated of the 530 differentially expressed genes. Also, highly up-regulated are hematopoietic transcription factors, including the "heptad" complex of factors. We show that Gpr56 (mouse and human) is a target of the heptad complex and is required for hematopoietic cluster formation during EHT. Our results identify the processes and regulators involved in EHT and reveal the surprising requirement for Gpr56 in generating the first HSCs. © 2015 Solaimani Kartalaei et al.

Gene transfer to pre-hematopoietic and committed hematopoietic precursors in the early mouse Yolk Sac: a comparative study between in situ electroporation and retroviral transduction

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Lécluse Yann

2007-07-01

Full Text Available Abstract Background Hematopoietic development in vertebrate embryos results from the sequential contribution of two pools of precursors independently generated. While intra-embryonic precursors harbour the features of hematopoietic stem cells (HSC, precursors formed earlier in the yolk sac (YS display limited differentiation and self-renewal potentials. The mechanisms leading to the generation of the precursors in both sites are still largely unknown, as are the molecular basis underlying their different potential. A possible approach to assess the role of candidate genes is to transfer or modulate their expression/activity in both sites. We thus designed and compared transduction protocols to target either native extra-embryonic precursors, or hematopoietic precursors. Results One transduction protocol involves transient modification of gene expression through in situ electroporation of the prospective blood islands, which allows the evolution of transfected mesodermal cells in their "normal" environment, upon organ culture. Following in situ electroporation of a GFP reporter construct into the YS cavity of embryos at post-streak (mesodermal/pre-hematopoietic precursors or early somite (hematopoietic precursors stages, high GFP expression levels as well as a good preservation of cell viability is observed in YS explants. Moreover, the erythro-myeloid progeny typical of the YS arises from GFP+ mesodermal cells or hematopoietic precursors, even if the number of targeted precursors is low. The second approach, based on retroviral transduction allows a very efficient transduction of large precursor numbers, but may only be used to target 8 dpc YS hematopoietic precursors. Again, transduced cells generate a progeny quantitatively and qualitatively similar to that of control YS. Conclusion We thus provide two protocols whose combination may allow a thorough study of both early and late events of hematopoietic development in the murine YS. In situ

Historical Perspective on the Current Renaissance for Hematopoietic Stem Cell Gene Therapy.

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Kohn, Donald B

2017-10-01

Gene therapy using hematopoietic stem cells (HSC) has developed over the past 3 decades, with progressive improvements in the efficacy and safety. Autologous transplantation of HSC modified with murine gammaretroviral vectors first showed clinical benefits for patients with several primary immune deficiencies, but some of these patients suffered complications from vector-related genotoxicity. Lentiviral vectors have been used recently for gene addition to HSC and have yielded clinical benefits for primary immune deficiencies, metabolic diseases, and hemoglobinopathies, without vector-related complications. Gene editing using site-specific endonucleases is emerging as a promising technology for gene therapy and is moving into clinical trials. Copyright © 2017 Elsevier Inc. All rights reserved.

PARASITIC INFECTIONS IN HEMATOPOIETIC STEM CELL TRANSPLANTATION

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Isidro Jarque

2016-07-01

Full Text Available Parasitic infections are rarely documented in hematopoietic stem cell transplant recipients. However, they may be responsible for fatal complications that are only diagnosed at autopsy. Increased awareness of the possibility of parasitic diseases both in autologous and allogeneic stem cell transplant patients is relevant not only for implementing preventive measures but also for performing an early diagnosis and starting appropriate therapy for these unrecognized but fatal infectious complications in hematopoietic transplant recipients. In this review, we will focus on parasitic diseases occurring in this population especially those with major clinical relevance including toxoplasmosis, American trypanosomiasis, leishmaniasis, malaria, and strongyloidiasis, among others, highlighting the diagnosis and management in hematopoietic transplant recipients.

Mobilization of primitive and committed hematopoietic progenitors in nonhuman primates treated with defibrotide and recombinant human granulocyte colony-stimulating factor.

Science.gov (United States)

Carlo-Stella, Carmelo; Di Nicola, Massimo; Longoni, Paolo; Milani, Raffaella; Milanesi, Marco; Guidetti, Anna; Haanstra, Krista; Jonker, Margaret; Cleris, Loredana; Magni, Michele; Formelli, Franca; Gianni, Alesssandro M

2004-01-01

The aim of this study was to evaluate the capacity of defibrotide in enhancing cytokine-induced hematopoietic mobilization in rhesus monkeys. Animals received recombinant human granulocyte colony-stimulating factor (rhG-CSF, 100 microg/kg/day SC for 5 days) and, after a 4- to 6-week washout period, were remobilized with defibrotide (15 mg/kg/hour continuous intravenous for 5 days) plus rhG-CSF. Hematopoietic mobilization was evaluated by complete blood counts, differential counts, as well as frequency and absolute numbers of colony-forming cells (CFCs), high-proliferative potential CFCs (HPP-CFCs), and long-term culture-initiating cells (LTC-ICs). Compared to baseline values, rhG-CSF increased circulating CFCs, HPP-CFCs, and LTC-ICs by 158-, 125-, and 67-fold, respectively; the same figures for defibrotide/rhG-CSF were 299-, 1452-, and 295-fold, respectively. Defibrotide/rhG-CSF treatment compared to rhG-CSF alone increased CFCs, HPP-CFCs, and LTC-ICs by 1.4- (35,089 vs 25,825, pdefibrotide treatment associated with a 5-day rhG-CSF treatment. Compared to rhG-CSF, defibrotide/rhG-CSF increased the mobilization of CFCs, HPP-CFCs, and LTC-ICs by 2- (31,128 vs 15,527, pdefibrotide enhances rhG-CSF-elicited mobilization of primitive and committed progenitors; and 2) a 2-day defibrotide injection is as effective as a 5-day injection.

Differential Requirements for c-Myc in Chronic Hematopoietic Hyperplasia and Acute Hematopoietic Malignancies in Pten-null Mice

Science.gov (United States)

Zhang, Jun; Xiao, Yechen; Guo, Yinshi; Breslin, Peter; Zhang, Shubin; Wei, Wei; Zhang, Zhou; Zhang, Jiwang

2011-01-01

Myeloproliferative disorders (MPDs), lymphoproliferative disorders (LPDs), acute T-lymphocytic or myeloid leukemia and T-lymphocytic lymphoma were developed in inducible Pten-knockout (Pten−/−) mice. The appearance of these multiple diseases in one animal model provides an opportunity to study the pathogenesis of multiple diseases simultaneously. To study whether Myc function is required for the development of these hematopoietic disorders in Pten−/− mice, we generated inducible Pten/Myc double-knockout mice (Pten−/−/Myc−/−). By comparing the hematopoietic phenotypes of these double-knockout mice with those of Pten−/− mice, we found that both sets of animals developed MPDs and LPDs. However, none of the compound-mutant mice developed acute leukemia or lymphoma. Interestingly, in contrast to the MPDs which developed in Pten−/− mice which are dominated by granulocytes, megakaryocytes predominate in the MPDs of Pten−/−/Myc−/− mice. Our study suggests that the deregulation of PI3K/Akt signaling in Pten−/− hematopoietic cells protects these cells from apoptotic cell death, resulting in chronic proliferative disorders. But due to the differential requirement for Myc in granulocyte as compared to megakaryocyte proliferation, Myc deletion converts Pten−/− MPDs from granulocyte-dominated to megakaryocyte-dominated conditions. Myc is absolutely required for the development of acute hematopoietic malignancies. PMID:21926961

Hematopoietic tissue repair under chronic low daily dose irradiation

International Nuclear Information System (INIS)

Seed, T.M.

1994-01-01

The capacity of the hematopoietic system to repair constantly accruing cellular damage under chronic, low daily dose gamma irradiation is essential for the maintenance of a functional hematopoietic system, and, in turn, long term survival. In certain individuals, however, such continuous cycles of damage and repair provide an essential inductive environment for selected types of hematopathologies, e.g., myeloid leukemia (ML). We have been studying temporal and causal relationships between hematopoietic capacity, associated repair functions, and propensities for hematologic disease in canines under variable levels of chronic radiation stress (0.3-26.3 cGy d -1 ). Results indicate that the maximum exposure rate tolerated by the hematopoietic system is highly individual-specific and is based largely on the degree to which repair capacity, and, in turn, hematopoietic restoration, is augmented under chronic exposure. In low-tolerance individuals (prone to aplastic anemia, subgroup (1), the failure to augment basic m-pair functions seemingly results in a progressive accumulation of genetic and cellular damage within vital progenitorial marrow compartments particularly marked within erythroid compartments. that results in loss of reproductive capacity and ultimately in collapse of the hematopoietic system. The high-tolerance individuals (radioaccomodated and either prone- or not prone to ML, subgroup 2 ampersand 3 appear to minimize the accumulating damage effect of daily exposures by extending repair functions, which preserves reproductive integrity and fosters regenerative hematopoietic responses. As the strength of the regenerative response manifests the extent of repair augmentation, the relatively strong response of high- tolerance individuals progressing to patent ML suggests an insufficiency of repair quality rather than repair quantity

Hematopoietic stem cell gene therapy for IFNγR1 deficiency protects mice from mycobacterial infections.

Science.gov (United States)

Hetzel, Miriam; Mucci, Adele; Blank, Patrick; Nguyen, Ariane Hai Ha; Schiller, Jan; Halle, Olga; Kühnel, Mark-Philipp; Billig, Sandra; Meineke, Robert; Brand, Daniel; Herder, Vanessa; Baumgärtner, Wolfgang; Bange, Franz-Christoph; Goethe, Ralph; Jonigk, Danny; Förster, Reinhold; Gentner, Bernhard; Casanova, Jean-Laurent; Bustamante, Jacinta; Schambach, Axel; Kalinke, Ulrich; Lachmann, Nico

2018-02-01

Mendelian susceptibility to mycobacterial disease is a rare primary immunodeficiency characterized by severe infections caused by weakly virulent mycobacteria. Biallelic null mutations in genes encoding interferon gamma receptor 1 or 2 ( IFNGR1 or IFNGR2 ) result in a life-threatening disease phenotype in early childhood. Recombinant interferon γ (IFN-γ) therapy is inefficient, and hematopoietic stem cell transplantation has a poor prognosis. Thus, we developed a hematopoietic stem cell (HSC) gene therapy approach using lentiviral vectors that express Ifnγr1 either constitutively or myeloid specifically. Transduction of mouse Ifnγr1 -/- HSCs led to stable IFNγR1 expression on macrophages, which rescued their cellular responses to IFN-γ. As a consequence, genetically corrected HSC-derived macrophages were able to suppress T-cell activation and showed restored antimycobacterial activity against Mycobacterium avium and Mycobacterium bovis Bacille Calmette-Guérin (BCG) in vitro. Transplantation of genetically corrected HSCs into Ifnγr1 -/- mice before BCG infection prevented manifestations of severe BCG disease and maintained lung and spleen organ integrity, which was accompanied by a reduced mycobacterial burden in lung and spleen and a prolonged overall survival in animals that received a transplant. In summary, we demonstrate an HSC-based gene therapy approach for IFNγR1 deficiency, which protects mice from severe mycobacterial infections, thereby laying the foundation for a new therapeutic intervention in corresponding human patients. © 2018 by The American Society of Hematology.

Relationship between spontaneous γH2AX foci formation and progenitor functions in circulating hematopoietic stem and progenitor cells among atomic-bomb survivors.

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Kajimura, Junko; Kyoizumi, Seishi; Kubo, Yoshiko; Misumi, Munechika; Yoshida, Kengo; Hayashi, Tomonori; Imai, Kazue; Ohishi, Waka; Nakachi, Kei; Weng, Nan-Ping; Young, Lauren F; Shieh, Jae-Hung; Moore, Malcolm A; van den Brink, Marcel R M; Kusunoki, Yoichiro

2016-05-01

Accumulated DNA damage in hematopoietic stem cells is a primary mechanism of aging-associated dysfunction in human hematopoiesis. About 70 years ago, atomic-bomb (A-bomb) radiation induced DNA damage and functional decreases in the hematopoietic system of A-bomb survivors in a radiation dose-dependent manner. The peripheral blood cell populations then recovered to a normal range, but accompanying cells derived from hematopoietic stem cells still remain that bear molecular changes possibly caused by past radiation exposure and aging. In the present study, we evaluated radiation-related changes in the frequency of phosphorylated (Ser-139) H2AX (γH2AX) foci formation in circulating CD34-positive/lineage marker-negative (CD34+Lin-) hematopoietic stem and progenitor cells (HSPCs) among 226Hiroshima A-bomb survivors. An association between the frequency of γH2AX foci formation in HSPCs and the radiation dose was observed, but the γH2AX foci frequency was not significantly elevated by past radiation. We found a negative correlation between the frequency of γH2AX foci formation and the length of granulocyte telomeres. A negative interaction effect between the radiation dose and the frequency of γH2AX foci was suggested in a proportion of a subset of HSPCs as assessed by the cobblestone area-forming cell assay (CAFC), indicating that the self-renewability of HSPCs may decrease in survivors who were exposed to a higher radiation dose and who had more DNA damage in their HSPCs. Thus, although many years after radiation exposure and with advancing age, the effect of DNA damage on the self-renewability of HSPCs may be modified by A-bomb radiation exposure. Copyright © 2016 Elsevier B.V. All rights reserved.

Hematopoietic Stem Cell Transplantation Using Preimplantation Genetic Diagnosis and Human Leukocyte Antigen Typing for Human Leukocyte Antigen-Matched Sibling Donor: A Turkish Multicenter Study.

Science.gov (United States)

Kurekci, Emin; Küpesiz, Alphan; Anak, Sema; Öztürk, Gülyüz; Gürsel, Orhan; Aksoylar, Serap; Ileri, Talia; Kuşkonmaz, Barış; Eker, İbrahim; Cetin, Mualla; Tezcan Karasu, Gülsün; Kaya, Zühre; Fışgın, Tunç; Ertem, Mehmet; Kansoy, Savaş; Yeşilipek, Mehmet Akif

2017-05-01

Preimplantation genetic diagnosis involves the diagnosis of a genetic disorder in embryos obtained through in vitro fertilization, selection of healthy embryos, and transfer of the embryos to the mother's uterus. Preimplantation genetic diagnosis has been used not only to avoid the risk of having an affected child, but it also offers, using HLA matching, preselection of potential HLA-genoidentical healthy donor progeny for an affected sibling who requires bone marrow transplantation. Here, we share the hematopoietic stem cell transplantation results of 52 patients with different benign and malign hematological or metabolic diseases or immunodeficiencies whose donors were siblings born with this technique in Turkey since 2008. The median age of the patients' at the time of the transplantation was 8 years (range, 3 to 16 years) and the median age of the donors was 2 years (range, .5 to 6 years). The most common indication for HSCT was thalassemia major (42 of all patients, 80%). The stem cell source in all of the transplantations was bone marrow. In 37 of the transplantations, umbilical cord blood of the same donor was also used. In 50 of the 52 patients, full engraftment was achieved with a mean of 4.6 × 10 6 CD 34 + cells per kg of recipient weight. Ninety-six percent of the patients have been cured through hematopoietic stem cell transplantation without any complication. Primary engraftment failure was seen in only 2 patients with thalassemia major. All of the donors and the patients are alive with good health status. Preimplantation genetic diagnosis with HLA matching offers a life-saving chance for patients who need transplantation but lack an HLA genoidentical donor. Copyright © 2017 The American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

Expression and function of β-adrenergic receptors in human hematopoietic cell lines

International Nuclear Information System (INIS)

Maeki, T.; Andersson, L.C.; Kontula, K.K.

1992-01-01

We investigated the expression and functional characteristics of β-adrenoceptors in a panel of 10 phenotypically different human hematopoietic cell lines. A binding assay with [ 125 I]iodocyanopindolol as the ligand revealed that cell lines of myelomonocytic or histiocytic derivation (HL-60, ML-2, RC-2A, U-937) expressed high numbers of β-adrenoceptors. An intermediate density of receptors was found in a non-T, non-B cell leukemia line (Nall-1), whereas T-cell (JM, CCRF-CEM), B-cell (Raji) or erythroleukemic cell lines (K-562, HEL) displayed minimala or undetectable binding of the radioligand. Isoprenaline-stimulated cAMP production by the cells correlated to their extent of β-adrenoceptor expression. Southern blot hybridization analysis of genomic DNA from the cell lines with a 32 P-labelled β 2 -adrenoceptor cDNA probe revealed no evidence for major rearrangement or amplification of the receptor gene. Incubation with isoprenaline in vitro suppressed the proliferation of the receptor-rich RC-2A cells but did not affect the growth rate of the receptor-deficient K-562 cells. Treatment with propranolol slightly enhanced the proliferation of the RC-2A cells but did not markedly alter the growth rate of two other cell lines, regardless of their β-adrenoceptor status. These findings indicate a regulatory influence by the sympathoadrenergic system on selected cells of the myelomonocytic lineage. (au)

H4 histamine receptors mediate cell cycle arrest in growth factor-induced murine and human hematopoietic progenitor cells.

Directory of Open Access Journals (Sweden)

Anne-France Petit-Bertron

Full Text Available The most recently characterized H4 histamine receptor (H4R is expressed preferentially in the bone marrow, raising the question of its role during hematopoiesis. Here we show that both murine and human progenitor cell populations express this receptor subtype on transcriptional and protein levels and respond to its agonists by reduced growth factor-induced cell cycle progression that leads to decreased myeloid, erythroid and lymphoid colony formation. H4R activation prevents the induction of cell cycle genes through a cAMP/PKA-dependent pathway that is not associated with apoptosis. It is mediated specifically through H4R signaling since gene silencing or treatment with selective antagonists restores normal cell cycle progression. The arrest of growth factor-induced G1/S transition protects murine and human progenitor cells from the toxicity of the cell cycle-dependent anticancer drug Ara-C in vitro and reduces aplasia in a murine model of chemotherapy. This first evidence for functional H4R expression in hematopoietic progenitors opens new therapeutic perspectives for alleviating hematotoxic side effects of antineoplastic drugs.

Hematopoietic (stem) cell development — how divergent are the roads taken?

NARCIS (Netherlands)

M.-L. Kauts (Mari-Liis); C.S. Vink (Chris); E.A. Dzierzak (Elaine)

2016-01-01

textabstractThe development of the hematopoietic system during early embryonic stages occurs in spatially and temporally distinct waves. Hematopoietic stem cells (HSC), the most potent and self-renewing cells of this system, are produced in the final ‘definitive’ wave of hematopoietic cell

Sequence typing of human adenoviruses isolated from Polish patients subjected to allogeneic hematopoietic stem cell transplantation - a single center experience.

Science.gov (United States)

Przybylski, Maciej; Rynans, Sylwia; Waszczuk-Gajda, Anna; Bilinski, Jarosław; Basak, Grzegorz W; Jędrzejczak, Wiesław W; Wróblewska, Marta; Młynarczyk, Grażyna; Dzieciątkowski, Tomasz

2018-03-28

Human adenoviruses (HAdV) from species A, B and C are commonly recognized as pathogens causing severe morbidity and mortality in hematopoietic stem cell transplant (HSCT) recipients. The purpose of the present study was to determine HAdV types responsible for viremia in HSCT recipients at a large tertiary hospital in Poland. Analysis of partial nucleotide sequences of HAdV hexon gene was used to type 40 clinical isolates of HAdV obtained from 40 HSCT recipients. We identified six different HAdV serotypes belonging to species B, C and E. We demonstrated high variability in sequences of detected HAdV types, and patients infected with the same HAdV types were not hospitalized at the same time, which suggests the low possibility of cross-infection. In almost all patients, anti-HAdV antibodies in IgG class were detected, which indicates a history of HAdV infection in the past. Clinical symptoms accompanying HAdV viremia were in 89%, and in 61.5% of individuals, HAdV was a sole pathogen detected. There were no cases with high-level HAdV viremia and severe systemic or organ infections. Graft-versus-host disease (GvHD) was present in patients infected with species B and C, but grade II of GvHD was observed only in patients infected with HAdV-B. The predominance of HAdV-C and common presence of anti-HAdV antibodies in IgG class may strongly suggest that most infections in the present study were reactivations of HAdV persisting into the patient's mucosa-associated lymphoid tissues. Variability of HAdV sequences suggests that cross-infections between patients were very rare. GvHD: graft-versus-host disease; HAdV: human adenoviruses; HSCT: hematopoietic stem cell transplantation.

A human thymic epithelial cell culture system for the promotion of lymphopoiesis from hematopoietic stem cells.

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Beaudette-Zlatanova, Britte C; Knight, Katherine L; Zhang, Shubin; Stiff, Patrick J; Zúñiga-Pflücker, Juan Carlos; Le, Phong T

2011-05-01

A human thymic epithelial cell (TEC) line expressing human leukocyte antigen-ABC and human leukocyte antigen-DR was engineered to overexpress murine Delta-like 1 (TEC-Dl1) for the purpose of establishing a human culture system that supports T lymphopoiesis from hematopoietic progenitor cells (HPCs). Cord blood or bone marrow HPCs were co-cultured with either the parental TEC line expressing low levels of the Notch ligands, Delta-like 1 and Delta-like 4, or with TEC-Dl1 to determine if these cell lines support human lymphopoiesis. In co-cultures with cord blood or bone marrow HPCs, TEC-Dl1 cells promote de novo generation of CD7(pos)CD1a(pos) T-lineage committed cells. Most CD7(pos)CD1a(hi) cells are CD4(pos)CD8(pos) double-positive (DP). We found that TEC-Dl1 cells are insufficient to generate mature CD3(hi) CD4(pos) or CD3(hi) CD8(pos) single-positive (SP) T cells from the CD4(pos)CD8(pos) DP T cells; however, we detected CD3(lo) cells within the DP and SP CD4 and CD8 populations. The CD3(lo) SP cells expressed lower levels of interleukin-2Rα and interleukin-7Rα compared to CD3(lo) DP cells. In contrast to the TEC-Dl1 line, the parental TEC-84 line expressing low levels of human Notch ligands permits HPC differentiation to the B-cell lineage. We report for the first time a human TEC line that supports lymphopoiesis from cord blood and bone marrow HPC. The TEC cell lines described herein provide a novel human thymic stroma model to study the contribution of human leukocyte antigen molecules and Notch ligands to T-cell commitment and maturation and could be utilized to promote lymphopoiesis for immune cell therapy. Copyright © 2011 ISEH - Society for Hematology and Stem Cells. Published by Elsevier Inc. All rights reserved.

Abnormal muscle and hematopoietic gene expression may be important for clinical morbidity in primary hyperparathyroidism

DEFF Research Database (Denmark)

Reppe, Sjur; Stilgren, Lis; Abrahamsen, Bo

2007-01-01

out in biopsies obtained before and 1 yr after parathyroidectomy in seven patients discovered by routine blood [Ca(2+)] screening. The tissue distribution of PTH receptor (PTHR1 and PTHR2) mRNAs were quantitated using real-time RT-PCR in unrelated persons to define PTH target tissues. Of about 10......, muscle, and hematopoietic cells have to be considered as one independent, important cause of molecular disease in PHPT leading to profound alterations in gene expression that may help explain symptoms like muscle fatigue, cardiovascular pathology, and precipitation of psychiatric illness....

Low/Negative Expression of PDGFR-α Identifies the Candidate Primary Mesenchymal Stromal Cells in Adult Human Bone Marrow

DEFF Research Database (Denmark)

Li, Hongzhe; Ghazanfari, Roshanak; Zacharaki, Dimitra

2014-01-01

Human bone marrow (BM) contains a rare population of nonhematopoietic mesenchymal stromal cells (MSCs), which are of central importance for the hematopoietic microenvironment. However, the precise phenotypic definition of these cells in adult BM has not yet been reported. In this study, we show...... exhibited high levels of genes associated with mesenchymal lineages and HSC supportive function. Moreover, lin(-)/CD45(-)/CD271(+)/CD140a(low/-) cells effectively mediated the ex vivo expansion of transplantable CD34(+) hematopoietic stem cells. Taken together, these data indicate that CD140a is a key...... that low/negative expression of CD140a (PDGFR-α) on lin(-)/CD45(-)/CD271(+) BM cells identified a cell population with very high MSC activity, measured as fibroblastic colony-forming unit frequency and typical in vitro and in vivo stroma formation and differentiation capacities. Furthermore, these cells...

Fetal liver stromal cells promote hematopoietic cell expansion

International Nuclear Information System (INIS)

Zhou, Kun; Hu, Caihong; Zhou, Zhigang; Huang, Lifang; Liu, Wenli; Sun, Hanying

2009-01-01

Future application of hematopoietic stem and progenitor cells (HSPCs) in clinical therapies largely depends on their successful expansion in vitro. Fetal liver (FL) is a unique hematopoietic organ in which hematopoietic cells markedly expand in number, but the mechanisms involved remain unclear. Stromal cells (StroCs) have been suggested to provide a suitable cellular environment for in vitro expansion of HSPCs. In this study, murine StroCs derived from FL at E14.5, with a high level of Sonic hedgehog (Shh) and Wnt expression, were found to have an increased ability to support the proliferation of HSPCs. This effect was inhibited by blocking Shh signaling. Supplementation with soluble Shh-N promoted the proliferation of hematopoietic cells by activating Wnt signaling. Our findings suggest that FL-derived StroCs support proliferation of HSPCs via Shh inducing an autocrine Wnt signaling loop. The use of FL-derived StroCs and regulation of the Shh pathway might further enhance HPSC expansion.

The influence of gender- and age-related differences in the radiosensitivity of hematopoietic progenitor cells detected in steady-state human peripheral blood

International Nuclear Information System (INIS)

Kato, Kengo; Kashiwakura, Ikuo; Kuwabara, Mikinori

2011-01-01

To investigate the importance of gender and aging on the individual radiosensitivity of lineage-committed myeloid hematopoietic stem/progenitor cells (HSPCs) detected in mononuclear cells (MNCs) of steady-state human peripheral blood (PB), the clonogenic survival of HPCs, including colony-forming unit-granulocyte macrophage; burst-forming unit-erythroid; colony-forming unit-granulocyte-erythroid-macrophage-megakaryocyte cells derived from MNCs exposed to 0.5 Gy and 2 Gy X-irradiation were estimated. MNCs were prepared from the buffy-coats of 59 healthy individual blood donors. The results showed that large individual differences exist in the number of HSPCs, as well as in the surviving fraction of cells. Furthermore, the number of progenitor cells strongly correlated with their surviving fraction, suggesting that the radiosensitivity of hematopoietic progenitor cells decreases with the number of cells in the 10 5 cells population. A statistically significant negative correlation was observed between the surviving fraction observed at a dose of 0.5 Gy and the age of an individual, however, none of these correlations were observed after 2 Gy irradiation. No statistically significant difference was observed in individual radiosensitivity between males and females at either radiation dose. The present results indicated a correlation between the individual responsiveness of HSPCs to ionizing irradiation, especially to low dose irradiation, and aging. (author)

Epigenetic Loss of MLH1 Expression in Normal Human Hematopoietic Stem Cell Clones is Defined by the Promoter CpG Methylation Pattern Observed by High-Throughput Methylation Specific Sequencing.

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Kenyon, Jonathan; Nickel-Meester, Gabrielle; Qing, Yulan; Santos-Guasch, Gabriela; Drake, Ellen; PingfuFu; Sun, Shuying; Bai, Xiaodong; Wald, David; Arts, Eric; Gerson, Stanton L

Normal human hematopoietic stem and progenitor cells (HPC) lose expression of MLH1 , an important mismatch repair (MMR) pathway gene, with age. Loss of MMR leads to replication dependent mutational events and microsatellite instability observed in secondary acute myelogenous leukemia and other hematologic malignancies. Epigenetic CpG methylation upstream of the MLH1 promoter is a contributing factor to acquired loss of MLH1 expression in tumors of the epithelia and proximal mucosa. Using single molecule high-throughput bisulfite sequencing we have characterized the CpG methylation landscape from -938 to -337 bp upstream of the MLH1 transcriptional start site (position +0), from 30 hematopoietic colony forming cell clones (CFC) either expressing or not expressing MLH1 . We identify a correlation between MLH1 promoter methylation and loss of MLH1 expression. Additionally, using the CpG site methylation frequencies obtained in this study we were able to generate a classification algorithm capable of sorting the expressing and non-expressing CFC. Thus, as has been previously described for many tumor cell types, we report for the first time a correlation between the loss of MLH1 expression and increased MLH1 promoter methylation in CFC derived from CD34 + selected hematopoietic stem and progenitor cells.

The Hematopoietic Stem Cell Therapy for Exploration of Space

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Ohi, S.

Departments of Biochemistry &Molecular Biology, Genetics &Human Genetics, Pediatrics &Child Long-duration space missions require countermeasures against severe/invasive disorders in astronauts that are caused by space environments, such as hematological/cardiac abnormalities, bone/muscle losses, immunodeficiency, neurological disorders, and cancer. Some, if not all, of these disorders may be amenable to hematopoietic stem cell therapy and gene therapy. Growing evidence indicates that hematopoietic stem cells (HSCs) possess extraordinary plasticity to differentiate not only to all types of blood cells but also to various tissues, including bone, muscle, skin, liver and neuronal cells. Therefore, our working hypothesis is that the hematopoietic stem cell-based therapy, herein called as the hematopoietic stem cell therapy (HSCT), might provide countermeasure/prevention for hematological abnormalities, bone and muscle losses in space, thereby maintaining astronauts' homeostasis. Our expertise lies in recombinant adeno-associated virus (rAAV)-mediated gene therapy for the hemoglobinopathies, -thalassemia and sickle cell disease (Ohi S, Kim BC, J Pharm Sci 85: 274-281, 1996; Ohi S, et al. Grav Space Biol Bull 14: 43, 2000). As the requisite steps in this protocol, we established procedures for purification of HSCs from both mouse and human bone marrow in 1 G. Furthermore, we developed an easily harvestable, long-term liquid suspension culture system, which lasts more than one year, for growing/expanding HSCs without stromal cells. Human globin cDNAs/gene were efficiently expressed from the rAAVs in the mouse HSCs in culture. Additionally, the NASA Rotating Wall Vessel (RWV) culture system is being optimized for the HSC growth/expansion. Thus, using these technologies, the above hypothesis is being investigated by the ground-based experiments as follows: 1) -thalassemic mice (C57BL/6-Hbbth/Hbbth, Hbd-minor) are transplanted with normal isologous HSCs to correct the

Regulated proliferation of primitive hematopoietic progenitor cells in long-term human marrow cultures

International Nuclear Information System (INIS)

Cashman, J.; Eaves, A.C.; Eaves, C.J.

1985-01-01

We have examined the cycling status of various classes of erythroid and granulopoietic progenitor populations maintained for many weeks in standard normal long-term human marrow cultures. These were initiated with a single inoculum of marrow aspirate and were routinely fed by weekly removal of half of the nonadherent cells and replacement of half of the growth medium. Progenitors of large erythroid colonies (more than eight erythroblast clusters) present in the nonadherent fraction and progenitors of small granulocyte/macrophage colonies (fewer than 500 cells) present in both the nonadherent and adherent fractions were found to be actively cycling at all times examined (28% to 63% kill following a 20-minute exposure to 20 microCi/mL of high specific activity 3 H-thymidine). In contrast, progenitors of large granulocyte/macrophage colonies (more than 500 cells) and progenitors of large erythroid colonies (more than eight erythroblast clusters), present in the adherent layer, consistently alternated between a quiescent state at the time of each weekly medium change and a proliferating state two to three days later (0% to 13% kill and 21% to 49% kill, respectively). Additional experiments revealed that the activation of primitive progenitors in the adherent layer was not dependent on the addition of fresh glutamine or hydrocortisone, nor on the physical manipulations involved in changing the growth medium. These studies provide the first direct evidence that normal long-term human marrow cultures support the continued turnover of a variety of early hematopoietic progenitor cell types. Further, they indicate that the proliferative activity of the most primitive of these progenitors is regulated by stage-specific cell-cell interactions that are subject to manipulation

The Role of Toll Like Receptors in Hematopoietic Malignancies

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Darlene Monlish

2016-09-01

Full Text Available Toll-like receptors (TLRs are a family of pattern recognition receptors (PRRs that shape the innate immune system by identifying pathogen-associated molecular patterns (PAMPS and host-derived damage associated molecular patterns (DAMPS. TLRs are widely expressed on both immune cells and non-immune cells, including hematopoietic stem and progenitor cells, effector immune cell populations, and endothelial cells. In addition to their well-known role in the innate immune response to acute infection or injury, accumulating evidence supports a role for TLRs in the development of hematopoietic and other malignancies. Several hematopoietic disorders, including lymphoproliferative disorders and myelodysplastic syndromes, which possess a high risk of transformation to leukemia, have been linked to aberrant TLR signaling. Furthermore, activation of TLRs leads to the induction of a number of pro-inflammatory cytokines and chemokines, which can promote tumorigenesis by driving cell proliferation and migration and providing a favorable microenvironment for tumor cells. Beyond hematopoietic malignancies, the upregulation of a number of TLRs has been linked to promoting tumor cell survival, proliferation, and metastasis in a variety of cancers, including those of the colon, breast, and lung. This review focuses on the contribution of TLRs to hematopoietic malignancies, highlighting the known direct and indirect effects of TLR signaling on tumor cells and their microenvironment. In addition, the utility of TLR agonists and antagonists as potential therapeutics in the treatment of hematopoietic malignancies is discussed.

Improved hematopoietic differentiation efficiency of gene-corrected beta-thalassemia induced pluripotent stem cells by CRISPR/Cas9 system.

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Song, Bing; Fan, Yong; He, Wenyin; Zhu, Detu; Niu, Xiaohua; Wang, Ding; Ou, Zhanhui; Luo, Min; Sun, Xiaofang

2015-05-01

The generation of beta-thalassemia (β-Thal) patient-specific induced pluripotent stem cells (iPSCs), subsequent homologous recombination-based gene correction of disease-causing mutations/deletions in the β-globin gene (HBB), and their derived hematopoietic stem cell (HSC) transplantation offers an ideal therapeutic solution for treating this disease. However, the hematopoietic differentiation efficiency of gene-corrected β-Thal iPSCs has not been well evaluated in the previous studies. In this study, we used the latest gene-editing tool, clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated 9 (Cas9), to correct β-Thal iPSCs; gene-corrected cells exhibit normal karyotypes and full pluripotency as human embryonic stem cells (hESCs) showed no off-targeting effects. Then, we evaluated the differentiation efficiency of the gene-corrected β-Thal iPSCs. We found that during hematopoietic differentiation, gene-corrected β-Thal iPSCs showed an increased embryoid body ratio and various hematopoietic progenitor cell percentages. More importantly, the gene-corrected β-Thal iPSC lines restored HBB expression and reduced reactive oxygen species production compared with the uncorrected group. Our study suggested that hematopoietic differentiation efficiency of β-Thal iPSCs was greatly improved once corrected by the CRISPR/Cas9 system, and the information gained from our study would greatly promote the clinical application of β-Thal iPSC-derived HSCs in transplantation.

Hematopoiesis and hematopoietic organs in arthropods.

Science.gov (United States)

Grigorian, Melina; Hartenstein, Volker

2013-03-01

Hemocytes (blood cells) are motile cells that move throughout the extracellular space and that exist in all clades of the animal kingdom. Hemocytes play an important role in shaping the extracellular environment and in the immune response. Developmentally, hemocytes are closely related to the epithelial cells lining the vascular system (endothelia) and the body cavity (mesothelia). In vertebrates and insects, common progenitors, called hemangioblasts, give rise to the endothelia and blood cells. In the adult animal, many differentiated hemocytes seem to retain the ability to proliferate; however, in most cases investigated closely, the bulk of hemocyte proliferation takes place in specialized hematopoietic organs. Hematopoietic organs provide an environment where undifferentiated blood stem cells are able to self-renew, and at the same time generate offspring that differentiate into different blood cell types. Hematopoiesis in vertebrates, taking place in the bone marrow, has been subject to intensive research by immunologists and stem cell biologists. Much less is known about blood cell formation in invertebrate animals. In this review, we will survey structural and functional properties of invertebrate hematopoietic organs, with a main focus on insects and other arthropod taxa. We will then discuss similarities, at the molecular and structural level, that are apparent when comparing the development of blood cells in hematopoietic organs of vertebrates and arthropods. Our comparative review is intended to elucidate aspects of the biology of blood stem cells that are more easily missed when focusing on one or a few model species.

Effect of low dose radiation on expression of hematopoietic growth factors secreted by human mesenchymal stem cells from bone marrow

International Nuclear Information System (INIS)

Yang Yan; Wang Guanjun; Zhu Jingyan; Wang Juan

2008-01-01

Objective: To study the changes of hematopoietic growth factors secreted by human mesenchymal stem cells from bone marrow (BM-MSC) pretreated with low dose radiation (LDR). Methods: The cultured P4 and P5 BM-MSCs were exposed to X rays at the doses of 50, 75 and 100 mGy (dose rate 12.5 mGy·min -1 ). The changes of levels of stem cell factor (SCF), IL-6, macrophage colony-stimulating factor (M-CSF) secreted by BM- MSCs pretreated with LDR were determined by ELISA method. Results: As compared with control group at the same time, the levels of SCF in experimental group had a tendency of increasing after 24 h and 48 h radiation, but only in 75 mGy group the SCF level was obviously increased (P<0.05). The levels of IL-6 in 50 and 75 mGy groups at 24 h and 48 h, in 100 mGy group at 24 h were obviously increased compared with control group (P< 0.05). The levels of M-CSF in all the groups at 24 h, 48 h and 72 h except for the 50 mGy dose at 72 h were also increased (P<0.05), it increased markedly in 75 mGy dose group at 72 h. Conclusion: LDR has hormesis effect on BM-MSCs. After LDR, the BM-MSCs grow faster and in a certain phase the expression levels of hematopoietic growth factors are increased. (authors)

Mobilization of hematopoietic stem and progenitor cells in mice

NARCIS (Netherlands)

Robinson, Simon N; van Os, Ronald P; Bunting, Kevin

2008-01-01

Animal models have added significantly to our understanding of the mechanism(s) of hematopoietic stem and progenitor cell (HSPC) mobilization. Such models suggest that changes in the interaction between the HSPC and the hematopoietic microenvironmental 'niche' (cellular and extracellular components)

Identification of the homing molecules that escort pluripotent stem cells-derived hematopoietic stem cells to their niches and human activated T-cells to inflammatory sites.

KAUST Repository

Ali, Amal J.

2017-01-01

Hematopoietic cells exploit the multistep paradigm of cell migration to ultimately enable them to perform their function. This process is dictated by the ability of adhesion molecules on the circulating hematopoietic cells to find their counter

The SKI proto-oncogene enhances the in vivo repopulation of hematopoietic stem cells and causes myeloproliferative disease.

Science.gov (United States)

Singbrant, Sofie; Wall, Meaghan; Moody, Jennifer; Karlsson, Göran; Chalk, Alistair M; Liddicoat, Brian; Russell, Megan R; Walkley, Carl R; Karlsson, Stefan

2014-04-01

The proto-oncogene SKI is highly expressed in human myeloid leukemia and also in murine hematopoietic stem cells. However, its operative relevance in these cells remains elusive. We have over-expressed SKI to define its intrinsic role in hematopoiesis and myeloid neoplasms, which resulted in a robust competitive advantage upon transplantation, a complete dominance of the stem and progenitor compartments, and a marked enhancement of myeloid differentiation at the expense of other lineages. Accordingly, enforced expression of SKI induced a gene signature associated with hematopoietic stem cells and myeloid differentiation, as well as hepatocyte growth factor signaling. Here we demonstrate that, in contrast to what has generally been assumed, the significant impact of SKI on hematopoiesis is independent of its ability to inhibit TGF-beta signaling. Instead, myeloid progenitors expressing SKI are partially dependent on functional hepatocyte growth factor signaling. Collectively our results demonstrate that SKI is an important regulator of hematopoietic stem cell activity and its overexpression leads to myeloproliferative disease.

Developmental Vitamin D Availability Impacts Hematopoietic Stem Cell Production

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Mauricio Cortes

2016-10-01

Full Text Available Vitamin D insufficiency is a worldwide epidemic affecting billions of individuals, including pregnant women and children. Despite its high incidence, the impact of active vitamin D3 (1,25(OHD3 on embryonic development beyond osteo-regulation remains largely undefined. Here, we demonstrate that 1,25(OHD3 availability modulates zebrafish hematopoietic stem and progenitor cell (HSPC production. Loss of Cyp27b1-mediated biosynthesis or vitamin D receptor (VDR function by gene knockdown resulted in significantly reduced runx1 expression and Flk1+cMyb+ HSPC numbers. Selective modulation in vivo and in vitro in zebrafish indicated that vitamin D3 acts directly on HSPCs, independent of calcium regulation, to increase proliferation. Notably, ex vivo treatment of human HSPCs with 1,25(OHD3 also enhanced hematopoietic colony numbers, illustrating conservation across species. Finally, gene expression and epistasis analysis indicated that CXCL8 (IL-8 was a functional target of vitamin D3-mediated HSPC regulation. Together, these findings highlight the relevance of developmental 1,25(OHD3 availability for definitive hematopoiesis and suggest potential therapeutic utility in HSPC expansion.

A defined, feeder-free, serum-free system to generate in vitro hematopoietic progenitors and differentiated blood cells from hESCs and hiPSCs.

Directory of Open Access Journals (Sweden)

Giorgia Salvagiotto

2011-03-01

Full Text Available Human ESC and iPSC are an attractive source of cells of high quantity and purity to be used to elucidate early human development processes, for drug discovery, and in clinical cell therapy applications. To efficiently differentiate pluripotent cells into a pure population of hematopoietic progenitors we have developed a new 2-dimensional, defined and highly efficient protocol that avoids the use of feeder cells, serum or embryoid body formation. Here we showed that a single matrix protein in combination with growth factors and a hypoxic environment is sufficient to generate from pluripotent cells hematopoietic progenitors capable of differentiating further in mature cell types of different lineages of the blood system. We tested the differentiation method using hESCs and 9 iPSC lines generated from different tissues. These data indicate the robustness of the protocol providing a valuable tool for the generation of clinical-grade hematopoietic cells from pluripotent cells.

Donor-specific Anti-HLA antibodies in allogeneic hematopoietic stem cell transplantation

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Sarah Morin-Zorman

2016-08-01

Full Text Available Allogeneic Hematopoietic Stem Cell Transplantation (AHSCT is a curative treatment for a wide variety of hematological diseases. In 30% of the cases, a geno-identical donor is available. Any other situation displays some level of Human Leukocyte Antigen (HLA incompatibility between donor and recipient. Deleterious effects of anti-HLA immunization have long been recognized in solid organ transplant recipients. More recently, anti-HLA immunization was shown to increase the risk of Primary Graft Failure (PGF, a severe complication of AHSCT that occurs in 3 to 4% of matched unrelated donor transplantation and up to 15% in cord blood transplantation and T-cell depleted haplo-identical stem cell transplantation. Rates of PGF in patients with DSA were reported to be between 24 to 83% with the highest rates in haplo-identical and cord blood transplantation recipients. This led to the recommendation of anti-HLA antibody screening to detect Donor Specific Antibodies (DSA in recipients prior to AHSCT. In this review, we highlight the role of anti-HLA antibodies in AHSCT and the mechanisms that may lead to PGF in patients with DSA, and discuss current issues in the field.

Direct observation of hematopoietic progenitor chimerism in fetal freemartin cattle

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Taponen Juhani

2007-11-01

Full Text Available Abstract Background Cattle twins are well known as blood chimeras. However, chimerism in the actual hematopoietic progenitor compartment has not been directly investigated. Here, we analyzed fetal liver of chimeric freemartin cattle by combining a new anti-bovine CD34 antibody and Y-chromosome specific in situ hybridization. Results Bull-derived CD34+ cells were detected in the liver of the female sibling (freemartin at 60 days gestation. The level of bull-derived CD34+ cells was lower in the freemartin than in its male siblings. Bull (Y+ and cow hematopoietic cells often occurred in separate clusters. Around clusters of Y+CD34+ cells, Y+CD34- cells were typically observed. The thymi were also strongly chimeric at 60 days of gestation. Conclusion The fetal freemartin liver contains clusters of bull-derived hematopoietic progenitors, suggesting clonal expansion and differentiation. Even the roots of the hematopoietic system in cattle twins are thus strongly chimeric from the early stages of fetal development. However, the hematopoietic seeding of fetal liver apparently started already before the onset of functional vascular anastomosis.

Why are hematopoietic stem cells so 'sexy'? on a search for developmental explanation.

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Ratajczak, M Z

2017-08-01

Evidence has accumulated that normal human and murine hematopoietic stem cells express several functional pituitary and gonadal sex hormones, and that, in fact, some sex hormones, such as androgens, have been employed for many years to stimulate hematopoiesis in patients with bone marrow aplasia. Interestingly, sex hormone receptors are also expressed by leukemic cell lines and blasts. In this review, I will discuss the emerging question of why hematopoietic cells express these receptors. A tempting hypothetical explanation for this phenomenon is that hematopoietic stem cells are related to subpopulation of migrating primordial germ cells. To support of this notion, the anatomical sites of origin of primitive and definitive hematopoiesis during embryonic development are tightly connected with the migratory route of primordial germ cells: from the proximal epiblast to the extraembryonic endoderm at the bottom of the yolk sac and then back to the embryo proper via the primitive streak to the aorta-gonado-mesonephros (AGM) region on the way to the genital ridges. The migration of these cells overlaps with the emergence of primitive hematopoiesis in the blood islands at the bottom of the yolk sac, and definitive hematopoiesis that occurs in hemogenic endothelium in the embryonic dorsal aorta in AGM region.

The biochemistry of hematopoietic stem cell development.

Science.gov (United States)

Kaimakis, P; Crisan, M; Dzierzak, E

2013-02-01

The cornerstone of the adult hematopoietic system and clinical treatments for blood-related disease is the cohort of hematopoietic stem cells (HSC) that is harbored in the adult bone marrow microenvironment. Interestingly, this cohort of HSCs is generated only during a short window of developmental time. In mammalian embryos, hematopoietic progenitor and HSC generation occurs within several extra- and intraembryonic microenvironments, most notably from 'hemogenic' endothelial cells lining the major vasculature. HSCs are made through a remarkable transdifferentiation of endothelial cells to a hematopoietic fate that is long-lived and self-renewable. Recent studies are beginning to provide an understanding of the biochemical signaling pathways and transcription factors/complexes that promote their generation. The focus of this review is on the biochemistry behind the generation of these potent long-lived self-renewing stem cells of the blood system. Both the intrinsic (master transcription factors) and extrinsic regulators (morphogens and growth factors) that affect the generation, maintenance and expansion of HSCs in the embryo will be discussed. The generation of HSCs is a stepwise process involving many developmental signaling pathways, morphogens and cytokines. Pivotal hematopoietic transcription factors are required for their generation. Interestingly, whereas these factors are necessary for HSC generation, their expression in adult bone marrow HSCs is oftentimes not required. Thus, the biochemistry and molecular regulation of HSC development in the embryo are overlapping, but differ significantly from the regulation of HSCs in the adult. HSC numbers for clinical use are limiting, and despite much research into the molecular basis of HSC regulation in the adult bone marrow, no panel of growth factors, interleukins and/or morphogens has been found to sufficiently increase the number of these important stem cells. An understanding of the biochemistry of HSC

Neural Crossroads in the Hematopoietic Stem Cell Niche.

Science.gov (United States)

Agarwala, Sobhika; Tamplin, Owen J

2018-05-29

The hematopoietic stem cell (HSC) niche supports steady-state hematopoiesis and responds to changing needs during stress and disease. The nervous system is an important regulator of the niche, and its influence is established early in development when stem cells are specified. Most research has focused on direct innervation of the niche, however recent findings show there are different modes of neural control, including globally by the central nervous system (CNS) and hormone release, locally by neural crest-derived mesenchymal stem cells, and intrinsically by hematopoietic cells that express neural receptors and neurotransmitters. Dysregulation between neural and hematopoietic systems can contribute to disease, however new therapeutic opportunities may be found among neuroregulator drugs repurposed to support hematopoiesis. Copyright © 2018 Elsevier Ltd. All rights reserved.

The effects of X-irradiation on ex vivo expansion of cryopreserved human hematopoietic stem/progenitor cells

International Nuclear Information System (INIS)

Hayashi, Naoki; Takahashi, Kenji; Kashiwakura, Ikuo

2010-01-01

In our previous study (Life Sciences 84: 598, 2009), we demonstrated that placental/umbilical cord blood-derived mesenchymal stem cell-like stromal cells have the effect to support the regeneration of freshly prepared X-irradiated hematopoietic stem/progenitor cells (HSPCs). Generally, HSPCs are supplied from companies, institutions, and cell banks that cryopreserve them for clinical and experimental use. In this study, the influence of cryopreservation on the responses of HSPCs to irradiation and co-culture with stromal cells is assessed. After cryopreservation with the optimal procedure, 2 Gy-irradiated HSPCs were cultured with or without stromal cells supplemented with combination of interleukin-3, stem cell factor, and thrombopoietin. The population of relatively immature CD34 + /CD38 - cells in cryopreserved cells was significantly higher than in fresh cells prior to cryopreservation; furthermore, the hematopoietic progenitor populations of CD34 + /CD45RA + cells and CD34 + /CD117 + cells in cryopreserved cells were significantly lower than that in fresh cells. However, the rate of expansion in the cryopreserved HSPCs was lower than in the fresh HSPCs. In the culture of cryopreserved cells irradiated with 2 Gy, the growth rates of CD34 + cells, CD34 + /CD38 - cells, and hematopoietic progenitors were greater than growth rates of their counter parts in the culture of fresh cells. Surprisingly, the effect to support the hematopoiesis in co-culture with stromal cells was never observed in the X-irradiated HSPCs after cryopreservation. The present results demonstrated that cryopreserving process increased the rate of immature and radio-resistant HSPCs but decreased the effects to support the hematopoiesis by stromal cells, thus suggesting that cryopreservation changes the character of HSPCs. (author)

Instruction of hematopoietic lineage choice by cytokine signaling

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Endele, Max; Etzrodt, Martin; Schroeder, Timm, E-mail: timm.schroeder@bsse.ethz.ch

2014-12-10

Hematopoiesis is the cumulative consequence of finely tuned signaling pathways activated through extrinsic factors, such as local niche signals and systemic hematopoietic cytokines. Whether extrinsic factors actively instruct the lineage choice of hematopoietic stem and progenitor cells or are only selectively allowing survival and proliferation of already intrinsically lineage-committed cells has been debated over decades. Recent results demonstrated that cytokines can instruct lineage choice. However, the precise function of individual cytokine-triggered signaling molecules in inducing cellular events like proliferation, lineage choice, and differentiation remains largely elusive. Signal transduction pathways activated by different cytokine receptors are highly overlapping, but support the production of distinct hematopoietic lineages. Cellular context, signaling dynamics, and the crosstalk of different signaling pathways determine the cellular response of a given extrinsic signal. New tools to manipulate and continuously quantify signaling events at the single cell level are therefore required to thoroughly interrogate how dynamic signaling networks yield a specific cellular response. - Highlights: • Recent studies provided definite proof for lineage-instructive action of cytokines. • Signaling pathways involved in hematopoietic lineage instruction remain elusive. • New tools are emerging to quantitatively study dynamic signaling networks over time.

Using Proteomics to 1) Identify the Bone Marrow Homing Receptors Expressed on Human Hematopoietic Stem Cells and 2) Elucidate Critical Signaling Pathways Responsible for the Blockage of Hematopoietic Differentiation in Leukemia

KAUST Repository

Chin, Chee J.

2011-01-01

Successful hematopoiesis requires the trafficking of hematopoietic stem/progenitor cells (HSPCs) to their bone marrow (BM) niche, where they can differentiate to produce all blood lineages. Leukemia arises when there is a blockage of differentiation

Catalase inhibits ionizing radiation-induced apoptosis in hematopoietic stem and progenitor cells.

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Xiao, Xia; Luo, Hongmei; Vanek, Kenneth N; LaRue, Amanda C; Schulte, Bradley A; Wang, Gavin Y

2015-06-01

Hematologic toxicity is a major cause of mortality in radiation emergency scenarios and a primary side effect concern in patients undergoing chemo-radiotherapy. Therefore, there is a critical need for the development of novel and more effective approaches to manage this side effect. Catalase is a potent antioxidant enzyme that coverts hydrogen peroxide into hydrogen and water. In this study, we evaluated the efficacy of catalase as a protectant against ionizing radiation (IR)-induced toxicity in hematopoietic stem and progenitor cells (HSPCs). The results revealed that catalase treatment markedly inhibits IR-induced apoptosis in murine hematopoietic stem cells and hematopoietic progenitor cells. Subsequent colony-forming cell and cobble-stone area-forming cell assays showed that catalase-treated HSPCs can not only survive irradiation-induced apoptosis but also have higher clonogenic capacity, compared with vehicle-treated cells. Moreover, transplantation of catalase-treated irradiated HSPCs results in high levels of multi-lineage and long-term engraftments, whereas vehicle-treated irradiated HSPCs exhibit very limited hematopoiesis reconstituting capacity. Mechanistically, catalase treatment attenuates IR-induced DNA double-strand breaks and inhibits reactive oxygen species. Unexpectedly, we found that the radioprotective effect of catalase is associated with activation of the signal transducer and activator of transcription 3 (STAT3) signaling pathway and pharmacological inhibition of STAT3 abolishes the protective activity of catalase, suggesting that catalase may protect HSPCs against IR-induced toxicity via promoting STAT3 activation. Collectively, these results demonstrate a previously unrecognized mechanism by which catalase inhibits IR-induced DNA damage and apoptosis in HSPCs.

Cognitive ability in children with chronic granulomatous disease: a comparison of those managed conservatively with those who have undergone hematopoietic stem cell transplant.

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Cole, Theresa S; McKendrick, Fiona; Cant, Andrew J; Pearce, Mark S; Cale, Catherine M; Goldblatt, David R; Gennery, Andrew R; Titman, Penny

2013-08-01

Chronic granulomatous disease (CGD) is a primary immunodeficiency managed conservatively or with hematopoietic stem cell transplant. Studies have shown people with CGD and those transplanted for primary immunodeficiencies have lower than average cognitive ability. In this study, IQ in children with CGD and those transplanted for it was within the normal range. Georg Thieme Verlag KG Stuttgart · New York.

Human Vav1 expression in hematopoietic and cancer cell lines is regulated by c-Myb and by CpG methylation.

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Lena Ilan

Full Text Available Vav1 is a signal transducer protein that functions as a guanine nucleotide exchange factor for the Rho/Rac GTPases in the hematopoietic system where it is exclusively expressed. Recently, Vav1 was shown to be involved in several human malignancies including neuroblastoma, lung cancer, and pancreatic ductal adenocarcinoma (PDA. Although some factors that affect vav1 expression are known, neither the physiological nor pathological regulation of vav1 expression is completely understood. We demonstrate herein that mutations in putative transcription factor binding sites at the vav1 promoter affect its transcription in cells of different histological origin. Among these sites is a consensus site for c-Myb, a hematopoietic-specific transcription factor that is also found in Vav1-expressing lung cancer cell lines. Depletion of c-Myb using siRNA led to a dramatic reduction in vav1 expression in these cells. Consistent with this, co-transfection of c-Myb activated transcription of a vav1 promoter-luciferase reporter gene construct in lung cancer cells devoid of Vav1 expression. Together, these results indicate that c-Myb is involved in vav1 expression in lung cancer cells. We also explored the methylation status of the vav1 promoter. Bisulfite sequencing revealed that the vav1 promoter was completely unmethylated in human lymphocytes, but methylated to various degrees in tissues that do not normally express vav1. The vav1 promoter does not contain CpG islands in proximity to the transcription start site; however, we demonstrated that methylation of a CpG dinucleotide at a consensus Sp1 binding site in the vav1 promoter interferes with protein binding in vitro. Our data identify two regulatory mechanisms for vav1 expression: binding of c-Myb and CpG methylation of 5' regulatory sequences. Mutation of other putative transcription factor binding sites suggests that additional factors regulate vav1 expression as well.

Generation of hematopoietic lineage cells from embryonic like cells

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Gholam Reza Khamisipour

2014-10-01

Full Text Available Background: Epigenetic reprogramming of somatic cells into embryonic stem cells has attracted much attention, because of the potential for stem cell transplantation and compatibility with recipient. However, the therapeutic application of either nuclear transfer or nuclear fusion of somatic cell has been hindered by technical complications as well as ethical objections. Recently, a new method is reported whereby ectopic expression of embryonic specific transcription factors was shown to induce fibroblasts to become embryonic like SCs (induced pluripotent stem cells. A major limitation of this method is the use of potentially harmful genome integrating viruses such as reto- or lentivirus. The main aim of this investigation was generation of human hematopoietic stem cells from induced fibroblasts by safe adenovectors carrying embryonically active genes. Material and Methods: Isolated fibroblasts from foreskin were expanded and recombinant adenoviruses carrying human Sox2, Oct4, Klf4, cMyc genes were added to culture. After formation of embryonic like colonies and cell expansion, they were transferred to embryonic media without bFGF, and embryoid bodies were cultured on stromal and non-stromal differentiation media for 14 days. Results: Expression of CD34 gene and antigenic markers, CD34, CD38 & CD133 in stromal culture showed significant difference with non-differentiation and non-stromal media. Conclusion: These findings show high hematopoietic differentiation rate of Adeno-iPS cells in stromal culture and no need to use growth factors. While, there was no difference between non-differentiation and non-stromal media.

Prostaglandin E2 regulates hematopoietic stem cell

International Nuclear Information System (INIS)

Wang Yingying; Zhou Daohong; Meng Aimin

2013-01-01

Prostaglandin E2 (PGE2) is a bioactive lipid molecule produced by cyclooxygenase (COX), which plays an important role on hematopoiesis. While it can block differentiation of myeloid progenitors but enhance proliferation of erythroid progenitors. Recent research found that PGE2 have the effects on hematopoietic stem cell (HSC) function and these effects were independent from effects on progenitor cells. Exposure of HSC cells to PGE2 in vitro can increase homing efficiency of HSC to the murine bone marrow compartment and decrease HSC apoptosis, meanwhile increase long-term stem cell engraftment. In-vivo treatment with PGE2 expands short-term HSC and engraftment in murine bone marrow but not long-term HSC.In addition, PGE2 increases HSC survival after radiation injury and enhance hematopoietic recovery, resulting maintains hematopoietic homeostasis. PGE2 regulates HSC homeostasis by reactive oxygen species and Wnt pathway. Clinical beneficial of 16, 16-dimethyl-prostaglandin E2 treatment to enhance engraftment of umbilical cord blood suggest important improvements to therapeutic strategies. (authors)

IL-7 Enhances Thymic Human T Cell Development in "Human Immune System" Rag2-/-IL-2R{gamma}c-/- Mice without Affecting Peripheral T Cell Homeostasis

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van Lent, Anja U.; Dontje, Wendy; Nagasawa, Maho; Siamari, Rachida; Bakker, Arjen Q.; Pouw, Stephan M.; Maijoor, Kelly A.; Weijer, Kees; Cornelissen, Jan J.; Blom, Bianca; Di Santo, James P.; Spits, Hergen; Legrand, Nicolas

2009-01-01

IL-7 is a central cytokine in the development of hematopoietic cells, although interspecies discrepancies have been reported. By coculturing human postnatal thymus hematopoietic progenitors and OP9-huDL1 stromal cells, we found that murine IL-7 is approximately 100-fold less potent than human IL-7

Improving Gene Therapy Efficiency through the Enrichment of Human Hematopoietic Stem Cells.

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Masiuk, Katelyn E; Brown, Devin; Laborada, Jennifer; Hollis, Roger P; Urbinati, Fabrizia; Kohn, Donald B

2017-09-06

Lentiviral vector (LV)-based hematopoietic stem cell (HSC) gene therapy is becoming a promising clinical strategy for the treatment of genetic blood diseases. However, the current approach of modifying 1 × 10 8 to 1 × 10 9 CD34 + cells per patient requires large amounts of LV, which is expensive and technically challenging to produce at clinical scale. Modification of bulk CD34 + cells uses LV inefficiently, because the majority of CD34 + cells are short-term progenitors with a limited post-transplant lifespan. Here, we utilized a clinically relevant, immunomagnetic bead (IB)-based method to purify CD34 + CD38 - cells from human bone marrow (BM) and mobilized peripheral blood (mPB). IB purification of CD34 + CD38 - cells enriched severe combined immune deficiency (SCID) repopulating cell (SRC) frequency an additional 12-fold beyond standard CD34 + purification and did not affect gene marking of long-term HSCs. Transplant of purified CD34 + CD38 - cells led to delayed myeloid reconstitution, which could be rescued by the addition of non-transduced CD38 + cells. Importantly, LV modification and transplantation of IB-purified CD34 + CD38 - cells/non-modified CD38 + cells into immune-deficient mice achieved long-term gene-marked engraftment comparable with modification of bulk CD34 + cells, while utilizing ∼7-fold less LV. Thus, we demonstrate a translatable method to improve the clinical and commercial viability of gene therapy for genetic blood cell diseases. Copyright © 2017 The American Society of Gene and Cell Therapy. Published by Elsevier Inc. All rights reserved.

Immunity and tolerance to fungi in hematopoietic transplantation: Principles and perspectives

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Agostinho eCarvalho

2012-06-01

Full Text Available Resistance and tolerance are two complementary host defence mechanism that increase fitness in response to low-virulence fungi. Resistance is meant to reduce pathogen burden during infection through innate and adaptive immune mechanisms, whereas tolerance mitigate the substantial cost of resistance to host fitness through a multitude of anti-inflammatory mechanisms, including immunological tolerance. In experimental fungal infections, both defense mechanisms are activated through the delicate equilibrium between Th1/Th17 cells, which provide antifungal resistance, and regulatory T cells limiting the consequences of the ensuing inflammatory pathology.Indoleamine 2,3-dioxygenase (IDO, a rate-limiting enzyme in the tryptophan catabolism, plays a key role in induction of tolerance against fungi. Both hematopoietic and nonhematopoietic compartments contribute to the resistance/tolerance balance against Aspergillus fumigatus via the involvement of selected innate receptors converging on IDO. Several genetic polymorphisms in pattern recognition receptors influence resistance and tolerance to fungal infections in human hematopoietic transplantation. Thus, tolerance mechanisms may be exploited for novel diagnostics and therapeutics against fungal infections and diseases.

The Hematopoietic Stem Cell Therapy for Exploration of Deep Space

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Ohi, Seigo; Roach, Allana-Nicole; Fitzgerald, Wendy; Riley, Danny A.; Gonda, Steven R.

2003-01-01

It is hypothesized that the hematopoietic stem cell therapy (HSCT) might countermeasure various space-caused disorders so as to maintain astronauts' homeostasis. If this were achievable, the HSCT could promote human exploration of deep space. Using animal models of disorders (hindlimb suspension unloading system and beta-thalassemia), the HSCT was tested for muscle loss, immunodeficiency and space anemia. The results indicate feasibility of HSCT for these disorders. To facilitate the HSCT in space, growth of HSCs were optimized in the NASA Rotating Wall Vessel (RWV) culture systems, including Hydrodynamic Focusing Bioreactor (HFB).

Transcriptome analysis of bone marrow mesenchymal stromal cells from patients with primary myelofibrosis

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Christophe Martinaud

2015-09-01

Full Text Available Primary myelofibrosis (PMF is a clonal myeloproliferative neoplasm whose severity and treatment complexity are attributed to the presence of bone marrow (BM fibrosis and alterations of stroma impairing the production of normal blood cells. Despite the recently discovered mutations including the JAK2V617F mutation in about half of patients, the primitive event responsible for the clonal proliferation is still unknown. In the highly inflammatory context of PMF, the presence of fibrosis associated with a neoangiogenesis and an osteosclerosis concomitant to the myeloproliferation and to the increase number of circulating hematopoietic progenitors suggests that the crosstalk between hematopoietic and stromal cells is deregulated in the PMF BM microenvironmental niches. Within these niches, mesenchymal stromal cells (BM-MSC play a hematopoietic supportive role in the production of growth factors and extracellular matrix which regulate the proliferation, differentiation, adhesion and migration of hematopoietic stem/progenitor cells. A transcriptome analysis of BM-MSC in PMF patients will help to characterize their molecular alterations and to understand their involvement in the hematopoietic stem/progenitor cell deregulation that features PMF.

Two new routes to make blood: Hematopoietic specification from pluripotent cell lines versus reprogramming of somatic cells.

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Singbrant, Sofie; van Galen, Peter; Lucas, Daniel; Challen, Grant; Rossi, Derrick J; Daley, George Q

2015-09-01

Transplantation of hematopoietic stem cells (HSCs) to treat hematologic disorders is routinely used in the clinic. However, HSC therapy is hindered by the requirements of finding human leukocyte antigen (HLA)-matched donors and attaining sufficient numbers of long-term HSCs in the graft. Therefore, ex vivo expansion of transplantable HSCs remains one of the "holy grails" of hematology. Without the ability to maintain and expand human HSCs in vitro, two complementary approaches involving cellular reprogramming to generate transplantable HSCs have emerged. Reprogrammed HSCs represent a potentially inexhaustible supply of autologous tissue. On March 18th, 2015, Dr. George Q. Daley and Dr. Derrick J. Rossi, two pioneers in the field, presented and discussed their most recent research on these topics in a webinar organized by the International Society for Experimental Hematology (ISEH). Here, we summarize these seminars and discuss the possibilities and challenges in the field of hematopoietic specification. Copyright © 2015 ISEH - International Society for Experimental Hematology. Published by Elsevier Inc. All rights reserved.

Generation of induced pluripotent stem cells as a potential source of hematopoietic stem cells for transplant in PNH patients.

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Phondeechareon, Tanapol; Wattanapanitch, Methichit; U-Pratya, Yaowalak; Damkham, Chanapa; Klincumhom, Nuttha; Lorthongpanich, Chanchao; Kheolamai, Pakpoom; Laowtammathron, Chuti; Issaragrisil, Surapol

2016-10-01

Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired hemolytic anemia caused by lack of CD55 and CD59 on blood cell membrane leading to increased sensitivity of blood cells to complement. Hematopoietic stem cell transplantation (HSCT) is the only curative therapy for PNH, however, lack of HLA-matched donors and post-transplant complications are major concerns. Induced pluripotent stem cells (iPSCs) derived from patients are an attractive source for generating autologous HSCs to avoid adverse effects resulting from allogeneic HSCT. The disease involves only HSCs and their progeny; therefore, other tissues are not affected by the mutation and may be used to produce disease-free autologous HSCs. This study aimed to derive PNH patient-specific iPSCs from human dermal fibroblasts (HDFs), characterize and differentiate to hematopoietic cells using a feeder-free protocol. Analysis of CD55 and CD59 expression was performed before and after reprogramming, and hematopoietic differentiation. Patients' dermal fibroblasts expressed CD55 and CD59 at normal levels and the normal expression remained after reprogramming. The iPSCs derived from PNH patients had typical pluripotent properties and differentiation capacities with normal karyotype. After hematopoietic differentiation, the differentiated cells expressed early hematopoietic markers (CD34 and CD43) with normal CD59 expression. The iPSCs derived from HDFs of PNH patients have normal levels of CD55 and CD59 expression and hold promise as a potential source of HSCs for autologous transplantation to cure PNH patients.

Hematopoietic microenvironment. Origin, lineage, and transplantability of the stromal cells in long-term bone marrow cultures from chimeric mice

International Nuclear Information System (INIS)

Perkins, S.; Fleischman, R.A.

1988-01-01

Studies of bone marrow transplant patients have suggested that the stromal cells of the in vitro hematopoietic microenvironment are transplantable into conditioned recipients. Moreover, in patients with myeloproliferative disorders, all of the stromal cells, which include presumptive endothelial cells, appear to be derived from hematopoietic precursors. To confirm these findings, we have constructed two chimeric mouse models: (a) traditional radiation chimeras, and (b) fetal chimeras, produced by placental injection of bone marrow into genetically anemic Wx/Wv fetuses, a technique that essentially precludes engraftment of nonhematopoietic cells. Using two-color indirect immunofluorescence, the stromal cells in long-term bone marrow culture derived from these chimeras were analyzed for donor or host origin by strain-specific H-2 antigens, and for cell lineage by a variety of other specific markers. 75-95% of the stromal cells were shown to be hematopoietic cells of the monocyte-macrophage lineage, based upon donor origin, phagocytosis, and expression of specific hematopoietic surface antigens. The remaining 5-25% of the stromal cells were exclusively host in origin. Apart from occasional fat cells, these cells uniformly expressed collagen type IV, laminin, and a surface antigen associated with endothelial cells. Since these endothelial-like cells are not transplantable into radiation or fetal chimeras, they are not derived from hematopoietic stem cells. The contrast between our findings and human studies suggests either unexpected species differences in the origin of stromal lineages or limitations in the previous methodology used to detect nonhematopoietic stromal cells

Superior Red Blood Cell Generation from Human Pluripotent Stem Cells Through a Novel Microcarrier-Based Embryoid Body Platform.

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Sivalingam, Jaichandran; Lam, Alan Tin-Lun; Chen, Hong Yu; Yang, Bin Xia; Chen, Allen Kuan-Liang; Reuveny, Shaul; Loh, Yuin-Han; Oh, Steve Kah-Weng

2016-08-01

In vitro generation of red blood cells (RBCs) from human embryonic stem cells and human induced pluripotent stem cells appears to be a promising alternate approach to circumvent shortages in donor-derived blood supplies for clinical applications. Conventional methods for hematopoietic differentiation of human pluripotent stem cells (hPSC) rely on embryoid body (EB) formation and/or coculture with xenogeneic cell lines. However, most current methods for hPSC expansion and EB formation are not amenable for scale-up to levels required for large-scale RBC generation. Moreover, differentiation methods that rely on xenogenic cell lines would face obstacles for future clinical translation. In this study, we report the development of a serum-free and chemically defined microcarrier-based suspension culture platform for scalable hPSC expansion and EB formation. Improved survival and better quality EBs generated with the microcarrier-based method resulted in significantly improved mesoderm induction and, when combined with hematopoietic differentiation, resulted in at least a 6-fold improvement in hematopoietic precursor expansion, potentially culminating in a 80-fold improvement in the yield of RBC generation compared to a conventional EB-based differentiation method. In addition, we report efficient terminal maturation and generation of mature enucleated RBCs using a coculture system that comprised primary human mesenchymal stromal cells. The microcarrier-based platform could prove to be an appealing strategy for future scale-up of hPSC culture, EB generation, and large-scale generation of RBCs under defined and xeno-free conditions.

Transmembrane Inhibitor of RICTOR/mTORC2 in Hematopoietic Progenitors

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Dongjun Lee

2014-11-01

Full Text Available Central to cellular proliferative, survival, and metabolic responses is the serine/threonine kinase mTOR, which is activated in many human cancers. mTOR is present in distinct complexes that are either modulated by AKT (mTORC1 or are upstream and regulatory of it (mTORC2. Governance of mTORC2 activity is poorly understood. Here, we report a transmembrane molecule in hematopoietic progenitor cells that physically interacts with and inhibits RICTOR, an essential component of mTORC2. Upstream of mTORC2 (UT2 negatively regulates mTORC2 enzymatic activity, reducing AKTS473, PKCα, and NDRG1 phosphorylation and increasing FOXO transcriptional activity in an mTORC2-dependent manner. Modulating UT2 levels altered animal survival in a T cell acute lymphoid leukemia (T-ALL model that is known to be mTORC2 sensitive. These studies identify an inhibitory component upstream of mTORC2 in hematopoietic cells that can reduce mortality from NOTCH-induced T-ALL. A transmembrane inhibitor of mTORC2 may provide an attractive target to affect this critical cell regulatory pathway.

Insulin-Like Growth Factor 1 Mitigates Hematopoietic Toxicity After Lethal Total Body Irradiation

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Zhou, Dunhua; Deoliveira, Divino; Kang, Yubin; Choi, Seung S. [Department of Medicine, Duke University Medical Center, Durham, North Carolina (United States); Li, Zhiguo [Department of Biostatistics and Bioinformatics, Duke University Medical Center, Durham, North Carolina (United States); Chao, Nelson J. [Department of Medicine, Duke University Medical Center, Durham, North Carolina (United States); Department of Pathology, Duke University Medical Center, Durham, North Carolina (United States); Department of Immunology, Duke University Medical Center, Durham, North Carolina (United States); Duke Cancer Institute, Duke University Medical Center, Durham, North Carolina (United States); Chen, Benny J., E-mail: chen0032@mc.duke.edu [Duke Cancer Institute, Duke University Medical Center, Durham, North Carolina (United States); Department of Medicine, Duke University Medical Center, Durham, North Carolina (United States)

2013-03-15

Purpose: To investigate whether and how insulin-like growth factor 1 (IGF-1) mitigates hematopoietic toxicity after total body irradiation. Methods and Materials: BALB/c mice were irradiated with a lethal dose of radiation (7.5 Gy) and treated with IGF-1 at a dose of 100 μg/dose intravenously once a day for 5 consecutive days starting within 1 hour after exposure. Survival and hematopoietic recovery were monitored. The mechanisms by which IGF-1 promotes hematopoietic recovery were also studied by use of an in vitro culture system. Results: IGF-1 protected 8 of 20 mice (40%) from lethal irradiation, whereas only 2 of 20 mice (10%) in the saline control group survived for more than 100 days after irradiation. A single dose of IGF-1 (500 μg) was as effective as daily dosing for 5 days. Positive effects were noted even when the initiation of treatment was delayed as long as 6 hours after irradiation. In comparison with the saline control group, treatment with IGF-1 significantly accelerated the recovery of both platelets and red blood cells in peripheral blood, total cell numbers, hematopoietic stem cells, and progenitor cells in the bone marrow when measured at day 14 after irradiation. IGF-1 protected both hematopoietic stem cells and progenitor cells from radiation-induced apoptosis and cell death. In addition, IGF-1 was able to facilitate the proliferation and differentiation of nonirradiated and irradiated hematopoietic progenitor cells. Conclusions: IGF-1 mitigates radiation-induced hematopoietic toxicity through protecting hematopoietic stem cells and progenitor cells from apoptosis and enhancing proliferation and differentiation of the surviving hematopoietic progenitor cells.

Insulin-Like Growth Factor 1 Mitigates Hematopoietic Toxicity After Lethal Total Body Irradiation

International Nuclear Information System (INIS)

Zhou, Dunhua; Deoliveira, Divino; Kang, Yubin; Choi, Seung S.; Li, Zhiguo; Chao, Nelson J.; Chen, Benny J.

2013-01-01

Purpose: To investigate whether and how insulin-like growth factor 1 (IGF-1) mitigates hematopoietic toxicity after total body irradiation. Methods and Materials: BALB/c mice were irradiated with a lethal dose of radiation (7.5 Gy) and treated with IGF-1 at a dose of 100 μg/dose intravenously once a day for 5 consecutive days starting within 1 hour after exposure. Survival and hematopoietic recovery were monitored. The mechanisms by which IGF-1 promotes hematopoietic recovery were also studied by use of an in vitro culture system. Results: IGF-1 protected 8 of 20 mice (40%) from lethal irradiation, whereas only 2 of 20 mice (10%) in the saline control group survived for more than 100 days after irradiation. A single dose of IGF-1 (500 μg) was as effective as daily dosing for 5 days. Positive effects were noted even when the initiation of treatment was delayed as long as 6 hours after irradiation. In comparison with the saline control group, treatment with IGF-1 significantly accelerated the recovery of both platelets and red blood cells in peripheral blood, total cell numbers, hematopoietic stem cells, and progenitor cells in the bone marrow when measured at day 14 after irradiation. IGF-1 protected both hematopoietic stem cells and progenitor cells from radiation-induced apoptosis and cell death. In addition, IGF-1 was able to facilitate the proliferation and differentiation of nonirradiated and irradiated hematopoietic progenitor cells. Conclusions: IGF-1 mitigates radiation-induced hematopoietic toxicity through protecting hematopoietic stem cells and progenitor cells from apoptosis and enhancing proliferation and differentiation of the surviving hematopoietic progenitor cells

Reduced Erg Dosage Impairs Survival of Hematopoietic Stem and Progenitor Cells.

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Xie, Ying; Koch, Mia Lee; Zhang, Xin; Hamblen, Melanie J; Godinho, Frank J; Fujiwara, Yuko; Xie, Huafeng; Klusmann, Jan-Henning; Orkin, Stuart H; Li, Zhe

2017-07-01

ERG, an ETS family transcription factor frequently overexpressed in human leukemia, has been implicated as a key regulator of hematopoietic stem cells. However, how ERG controls normal hematopoiesis, particularly at the stem and progenitor cell level, and how it contributes to leukemogenesis remain incompletely understood. Using homologous recombination, we generated an Erg knockdown allele (Erg kd ) in which Erg expression can be conditionally restored by Cre recombinase. Erg kd/kd animals die at E10.5-E11.5 due to defects in endothelial and hematopoietic cells, but can be completely rescued by Tie2-Cre-mediated restoration of Erg in these cells. In Erg kd/+ mice, ∼40% reduction in Erg dosage perturbs both fetal liver and bone marrow hematopoiesis by reducing the numbers of Lin - Sca-1 + c-Kit + (LSK) hematopoietic stem and progenitor cells (HSPCs) and megakaryocytic progenitors. By genetic mosaic analysis, we find that Erg-restored HSPCs outcompete Erg kd/+ HSPCs for contribution to adult hematopoiesis in vivo. This defect is in part due to increased apoptosis of HSPCs with reduced Erg dosage, a phenotype that becomes more drastic during 5-FU-induced stress hematopoiesis. Expression analysis reveals that reduced Erg expression leads to changes in expression of a subset of ERG target genes involved in regulating survival of HSPCs, including increased expression of a pro-apoptotic regulator Bcl2l11 (Bim) and reduced expression of Jun. Collectively, our data demonstrate that ERG controls survival of HSPCs, a property that may be used by leukemic cells. Stem Cells 2017;35:1773-1785. © 2017 AlphaMed Press.

Bone marrow adipocytes as negative regulators of the hematopoietic microenvironment

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Naveiras, Olaia; Nardi, Valentina; Wenzel, Pamela L.; Fahey, Frederic; Daley, George Q.

2009-01-01

Osteoblasts and endothelium constitute functional niches that support hematopoietic stem cells (HSC) in mammalian bone marrow (BM) 1,2,3 . Adult BM also contains adipocytes, whose numbers correlate inversely with the hematopoietic activity of the marrow. Fatty infiltration of hematopoietic red marrow follows irradiation or chemotherapy and is a diagnostic feature in biopsies from patients with marrow aplasia 4. To explore whether adipocytes influence hematopoiesis or simply fill marrow space, we compared the hematopoietic activity of distinct regions of the mouse skeleton that differ in adiposity. By flow cytometry, colony forming activity, and competitive repopulation assay, HSCs and short-term progenitors are reduced in frequency in the adipocyte-rich vertebrae of the mouse tail relative to the adipocyte-free vertebrae of the thorax. In lipoatrophic A-ZIP/F1 “fatless” mice, which are genetically incapable of forming adipocytes8, and in mice treated with the PPARγ inhibitor Bisphenol-A-DiGlycidyl-Ether (BADGE), which inhibits adipogenesis9, post-irradiation marrow engraftment is accelerated relative to wild type or untreated mice. These data implicate adipocytes as predominantly negative regulators of the bone marrow microenvironment, and suggest that antagonizingmarrow adipogenesis may enhance hematopoietic recovery in clinical bone marrow transplantation. PMID:19516257

HANPP Collection: Human Appropriation of Net Primary Productivity as a Percentage of Net Primary Productivity

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National Aeronautics and Space Administration — The Human Appropriation of Net Primary Productivity (HANPP) as a Percentage of Net Primary Product (NPP) portion of the HANPP Collection represents a map identifying...

Generation and Characterization of Anti-CD34 Monoclonal Antibodies that React with Hematopoietic Stem Cells

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Aghebati Maleki, Leili; Majidi, Jafar; Baradaran, Behzad; Movassaghpour, Aliakbar; Abdolalizadeh, Jalal

2014-01-01

CD34 is a type I membrane protein with a molecular mass of approximately 110 kDa. This antigen is associated with human hematopoietic progenitor cells and is a differentiation stage-specific leukocyte antigen. In this study we have generated and characterized monoclonal antibodies (mAbs) directed against a CD34 marker. Mice were immunized with two keyhole lympet hemocyanin (KLH)-conjugated CD34 peptides. Fused cells were grown in hypoxanthine, aminopterine and thymidine (HAT) selective medium and cloned by the limiting dilution (L.D) method. Several monoclones were isolated by three rounds of limited dilutions. From these, we chose stable clones that presented sustained antibody production for subsequent characterization. Antibodies were tested for their reactivity and specificity to recognize the CD34 peptides and further screened by enzyme-linked immunosorbent assay (ELISA) and Western blotting analyses. One of the mAbs (3D5) was strongly reactive against the CD34 peptide and with native CD34 from human umbilical cord blood cells (UCB) in ELISA and Western blotting analyses. The results have shown that this antibody is highly specific and functional in biomedical applications such as ELISA and Western blot assays. This monoclonal antibodies (mAb) can be a useful tool for isolation and purification of human hematopoietic stem cells (HSCs). PMID:24611141

Thioredoxin mitigates radiation-induced hematopoietic stem cell injury in mice

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Pasupathi Sundaramoorthy

2017-11-01

-induced double-strand DNA breaks in both murine bone marrow lineage-negative (Lin– cells and primary fibroblasts. Furthermore, TXN decreased the expression of p16 and phosphorylated p38. Our data suggest that TXN modulates diverse cellular processes of HSCs. Conclusions Administration of TXN 24 h following irradiation mitigates radiation-induced lethality. To the best of our knowledge, this is the first report demonstrating that TXN reduces radiation-induced lethality. TXN shows potential utility in the mitigation of radiation-induced hematopoietic injury.

Hematopoietic cell phosphatase is recruited to CD22 following B cell antigen receptor ligation

NARCIS (Netherlands)

Lankester, A. C.; van Schijndel, G. M.; van Lier, R. A.

1995-01-01

Hematopoietic cell phosphatase is a nonreceptor protein tyrosine phosphatase that is preferentially expressed in hematopoietic cell lineages. Motheaten mice, which are devoid of (functional) hematopoietic cell phosphatase, have severe disturbances in the regulation of B cell activation and

Contribution of endothelial progenitors and proangiogenic hematopoietic cells to vascularization of tumor and ischemic tissue

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Kopp, Hans-Georg; Ramos, Carlos A.; Rafii, Shahin

2010-01-01

Purpose of review During the last several years, a substantial amount of evidence from animal as well as human studies has advanced our knowledge of how bone marrow derived cells contribute to neoangiogenesis. In the light of recent findings, we may have to redefine our thinking of endothelial cells as well as of perivascular mural cells. Recent findings Inflammatory hematopoietic cells, such as macrophages, have been shown to promote neoangiogenesis during tumor growth and wound healing. Dendritic cells, B lymphocytes, monocytes, and other immune cells have also been found to be recruited to neoangiogenic niches and to support neovessel formation. These findings have led to the concept that subsets of hematopoietic cells comprise proangiogenic cells that drive adult revascularization processes. While evidence of the importance of endothelial progenitor cells in adult vasculogenesis increased further, the role of these comobilized hematopoietic cells has been intensely studied in the last few years. Summary Angiogenic factors promote mobilization of vascular endothelial growth factor receptor 1-positive hematopoietic cells through matrix metalloproteinase-9 mediated release of soluble kit-ligand and recruit these proangiogenic cells to areas of hypoxia, where perivascular mural cells present stromal-derived factor 1 (CXCL-12) as an important retention signal. The same factors are possibly involved in mobilization of vascular endothelial growth factor receptor 2-positive endothelial precursors that may participate in neovessel formation. The complete characterization of mechanisms, mediators and signaling pathways involved in these processes will provide novel targets for both anti and proangiogenic therapeutic strategies. PMID:16567962

ZFP521 regulates murine hematopoietic stem cell function and facilitates MLL-AF9 leukemogenesis in mouse and human cells.

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Garrison, Brian S; Rybak, Adrian P; Beerman, Isabel; Heesters, Balthasar; Mercier, Francois E; Scadden, David T; Bryder, David; Baron, Roland; Rossi, Derrick J

2017-08-03

The concept that tumor-initiating cells can co-opt the self-renewal program of endogenous stem cells as a means of enforcing their unlimited proliferative potential is widely accepted, yet identification of specific factors that regulate self-renewal of normal and cancer stem cells remains limited. Using a comparative transcriptomic approach, we identify ZNF521 / Zfp521 as a conserved hematopoietic stem cell (HSC)-enriched transcription factor in human and murine hematopoiesis whose function in HSC biology remains elusive. Competitive serial transplantation assays using Zfp521 -deficient mice revealed that ZFP521 regulates HSC self-renewal and differentiation. In contrast, ectopic expression of ZFP521 in HSCs led to a robust maintenance of progenitor activity in vitro. Transcriptional analysis of human acute myeloid leukemia (AML) patient samples revealed that ZNF521 is highly and specifically upregulated in AMLs with MLL translocations. Using an MLL-AF9 murine leukemia model and serial transplantation studies, we show that ZFP521 is not required for leukemogenesis, although its absence leads to a significant delay in leukemia onset. Furthermore, knockdown of ZNF521 reduced proliferation in human leukemia cell lines possessing MLL-AF9 translocations. Taken together, these results identify ZNF521/ZFP521 as a critical regulator of HSC function, which facilitates MLL-AF9-mediated leukemic disease in mice.

Primary ciliogenesis defects are associated with human astrocytoma/glioblastoma cells

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Rattner Jerome B

2009-12-01

Full Text Available Abstract Background Primary cilia are non-motile sensory cytoplasmic organelles that have been implicated in signal transduction, cell to cell communication, left and right pattern embryonic development, sensation of fluid flow, regulation of calcium levels, mechanosensation, growth factor signaling and cell cycle progression. Defects in the formation and/or function of these structures underlie a variety of human diseases such as Alström, Bardet-Biedl, Joubert, Meckel-Gruber and oral-facial-digital type 1 syndromes. The expression and function of primary cilia in cancer cells has now become a focus of attention but has not been studied in astrocytomas/glioblastomas. To begin to address this issue, we compared the structure and expression of primary cilia in a normal human astrocyte cell line with five human astrocytoma/glioblastoma cell lines. Methods Cultured normal human astrocytes and five human astrocytoma/glioblastoma cell lines were examined for primary cilia expression and structure using indirect immunofluorescence and electron microscopy. Monospecific antibodies were used to detect primary cilia and map the relationship between the primary cilia region and sites of endocytosis. Results We show that expression of primary cilia in normal astrocytes is cell cycle related and the primary cilium extends through the cell within a unique structure which we show to be a site of endocytosis. Importantly, we document that in each of the five astrocytoma/glioblastoma cell lines fully formed primary cilia are either expressed at a very low level, are completely absent or have aberrant forms, due to incomplete ciliogenesis. Conclusions The recent discovery of the importance of primary cilia in a variety of cell functions raises the possibility that this structure may have a role in a variety of cancers. Our finding that the formation of the primary cilium is disrupted in cells derived from astrocytoma/glioblastoma tumors provides the first

Environmental and chemotherapeutic agents induce breakage at genes involved in leukemia-causing gene rearrangements in human hematopoietic stem/progenitor cells

Energy Technology Data Exchange (ETDEWEB)

Thys, Ryan G., E-mail: rthys@wakehealth.edu [Department of Cancer Biology, Wake Forest School of Medicine, Medical Center Boulevard, Winston-Salem, NC 27157-1016 (United States); Lehman, Christine E., E-mail: clehman@wakehealth.edu [Department of Cancer Biology, Wake Forest School of Medicine, Medical Center Boulevard, Winston-Salem, NC 27157-1016 (United States); Pierce, Levi C.T., E-mail: Levipierce@gmail.com [Human Longevity, Inc., San Diego, California 92121 (United States); Wang, Yuh-Hwa, E-mail: yw4b@virginia.edu [Department of Biochemistry and Molecular Genetics, University of Virginia, 1340 Jefferson Park Avenue, Charlottesville, VA 22908-0733 (United States)

2015-09-15

Highlights: • Environmental/chemotherapeutic agents cause DNA breakage in MLL and CBFB in HSPCs. • Diethylnitrosamine-induced DNA breakage at MLL and CBFB shown for the first time. • Chemical-induced DNA breakage occurs at topoisomerase II cleavage sites. • Chemical-induced DNA breaks display a pattern similar to those in leukemia patients. • Long-term exposures suggested to generate DNA breakage at leukemia-related genes. - Abstract: Hematopoietic stem and progenitor cells (HSPCs) give rise to all of the cells that make up the hematopoietic system in the human body, making their stability and resilience especially important. Damage to these cells can severely impact cell development and has the potential to cause diseases, such as leukemia. Leukemia-causing chromosomal rearrangements have largely been studied in the context of radiation exposure and are formed by a multi-step process, including an initial DNA breakage and fusion of the free DNA ends. However, the mechanism for DNA breakage in patients without previous radiation exposure is unclear. Here, we investigate the role of non-cytotoxic levels of environmental factors, benzene, and diethylnitrosamine (DEN), and chemotherapeutic agents, etoposide, and doxorubicin, in generating DNA breakage at the patient breakpoint hotspots of the MLL and CBFB genes in human HSPCs. These conditions represent exposure to chemicals encountered daily or residual doses from chemotherapeutic drugs. Exposure of HSPCs to non-cytotoxic levels of environmental chemicals or chemotherapeutic agents causes DNA breakage at preferential sites in the human genome, including the leukemia-related genes MLL and CBFB. Though benzene, etoposide, and doxorubicin have previously been linked to leukemia formation, this is the first study to demonstrate a role for DEN in the generation of DNA breakage at leukemia-specific sites. These chemical-induced DNA breakpoints coincide with sites of predicted topoisomerase II cleavage. The

Environmental and chemotherapeutic agents induce breakage at genes involved in leukemia-causing gene rearrangements in human hematopoietic stem/progenitor cells

International Nuclear Information System (INIS)

Thys, Ryan G.; Lehman, Christine E.; Pierce, Levi C.T.; Wang, Yuh-Hwa

2015-01-01

Highlights: • Environmental/chemotherapeutic agents cause DNA breakage in MLL and CBFB in HSPCs. • Diethylnitrosamine-induced DNA breakage at MLL and CBFB shown for the first time. • Chemical-induced DNA breakage occurs at topoisomerase II cleavage sites. • Chemical-induced DNA breaks display a pattern similar to those in leukemia patients. • Long-term exposures suggested to generate DNA breakage at leukemia-related genes. - Abstract: Hematopoietic stem and progenitor cells (HSPCs) give rise to all of the cells that make up the hematopoietic system in the human body, making their stability and resilience especially important. Damage to these cells can severely impact cell development and has the potential to cause diseases, such as leukemia. Leukemia-causing chromosomal rearrangements have largely been studied in the context of radiation exposure and are formed by a multi-step process, including an initial DNA breakage and fusion of the free DNA ends. However, the mechanism for DNA breakage in patients without previous radiation exposure is unclear. Here, we investigate the role of non-cytotoxic levels of environmental factors, benzene, and diethylnitrosamine (DEN), and chemotherapeutic agents, etoposide, and doxorubicin, in generating DNA breakage at the patient breakpoint hotspots of the MLL and CBFB genes in human HSPCs. These conditions represent exposure to chemicals encountered daily or residual doses from chemotherapeutic drugs. Exposure of HSPCs to non-cytotoxic levels of environmental chemicals or chemotherapeutic agents causes DNA breakage at preferential sites in the human genome, including the leukemia-related genes MLL and CBFB. Though benzene, etoposide, and doxorubicin have previously been linked to leukemia formation, this is the first study to demonstrate a role for DEN in the generation of DNA breakage at leukemia-specific sites. These chemical-induced DNA breakpoints coincide with sites of predicted topoisomerase II cleavage. The

Ubiquitous expression of MAKORIN-2 in normal and malignant hematopoietic cells and its growth promoting activity.

Directory of Open Access Journals (Sweden)

King Yiu Lee

Full Text Available Makorin-2 (MKRN2 is a highly conserved protein and yet its functions are largely unknown. We investigated the expression levels of MKRN2 and RAF1 in normal and malignant hematopoietic cells, and leukemia cell lines. We also attempted to delineate the role of MKRN2 in umbilical cord blood CD34+ stem/progenitor cells and K562 cell line by over-expression and inhibition of MKRN2 through lentivirus transduction and shRNA nucleofection, respectively. Our results provided the first evidence on the ubiquitous expression of MKRN2 in normal hematopoietic cells, embryonic stem cell lines, primary leukemia and leukemic cell lines of myeloid, lymphoid, erythroid and megakaryocytic lineages. The expression levels of MKRN2 were generally higher in primary leukemia samples compared with those in age-matched normal BM cells. In all leukemia subtypes, there was no significant correlation between expression levels of MKRN2 and RAF1. sh-MKRN2-silenced CD34+ cells had a significantly lower proliferation capacity and decreased levels of the early stem/progenitor subpopulation (CFU-GEMM compared with control cultures. Over-expression of MKRN2 in K562 cells increased cell proliferation. Our results indicated possible roles of MKRN2 in normal and malignant hematopoiesis.

Analysis of glycoprotein E-selectin ligANDs on human and mouse marrow cells enriched for hematopoietic stem/progenitor cells

KAUST Repository

Merzaban, Jasmeen S.

2011-06-09

Although well recognized that expression of E-selectin on marrow microvessels mediates osteotropism of hematopoietic stem/progenitor cells (HSPCs), our knowledge regarding the cognate E-selectin ligand(s) on HSPCs is incomplete. Flow cytometry using E-selectin-Ig chimera (E-Ig) shows that human marrow cells enriched for HSPCs (CD34+ cells) display greater E-selectin binding than those obtained from mouse (lin-/Sca-1+/c-kit+ [LSK] cells). To define the relevant glycoprotein E-selectin ligands, lysates from human CD34+ and KG1a cells and from mouse LSK cells were immunoprecipitated using E-Ig and resolved byWestern blot using E-Ig. In both human and mouse cells, E-selectin ligand reactivity was observed at ∼ 120- to 130-kDa region, which contained two E-selectin ligands, the P-selectin glycoprotein ligand- 1 glycoform "CLA," and CD43. Human, but not mouse, cells displayed a prominent ∼ 100-kDa band, exclusively comprising the CD44 glycoform "HCELL."E-Ig reactivity was most prominent on CLA in mouse cells and on HCELL in human cells. To further assess HCELL\\'s contribution to E-selectin adherence, complementary studies were performed to silence (via CD44 siRNA) or enforce its expression (via exoglycosylation). Under physiologic shear conditions, CD44/HCELL-silenced human cells showed striking decreases (> 50%) in E-selectin binding. Conversely, enforced HCELL expression of LSK cells profoundly increased E-selectin adherence, yielding > 3-fold more marrow homing in vivo. These data define the key glycoprotein E-selectin ligands of human and mouse HSPCs, unveiling critical species-intrinsic differences in both the identity and activity of these structures. © 2011 by The American Society of Hematology.

Gene editing in hematopoietic stem cells: a potential therapeutic approach for Fanconi anemia

International Nuclear Information System (INIS)

Diez Cabezas, B.

2015-01-01

Gene therapy nowadays constitutes a safe and efficient treatment for a number of monogenic diseases affecting the hematopoietic system. Risks of insertional mutagenesis derived from the use of integrative vectors cannot, however, be completely excluded. Therefore, gene targeting has been proposed as a safer alternative, since the insertion of the herapeutic gene is driven to a specific locus in the genome. Gene targeting approaches are based on the use of specific nucleases which generate double strand breaks (DSBs) in a specific site of the genome,markedly enhancing the efficacy of homologous recombination (HR) with donor constructs harboring the gene of interest flanked by the corresponding homology arms. In this study we have optimized the conditions to target human lymphoblastic cell lines (LCLs) and also hematopoietic stem cells (HSCs) from healthy donors, with the final aim of correcting by gene editing the hematopoietic progenitor cells from Fanconi anemia subtype A (FA-A) patients. In particular, we have established a robust method to target both LCLs and HSCs in a safe harbor site in the genome, the AAVS1 locus. Our approach is based on the transduction of these cells with integrase-defective lentiviral vectors carrying a donor with the gene of interest, followed by the nucleofection of these cells with zinc finger nucleases used as mRNA. Using a control donor vector carrying the GFP reporter gene we have obtained, on average, 9.43% gene targeting efficiency in cord blood CD34+ cells from healthy donors. Moreover, we confirmed that gene targeting was also efficient in HSCs with long term and multipotent repopulation capacity, as demonstrated by transplants into immunodeficient mice. To improve the gene targeting efficiency, we investigated the feasibility of using gold nanoparticles, which were shown to improve the transduction efficiency of integrase-defective and competent lentiviral vectors in HSCs. This increment, however, did not lead to a higher gene

Gene editing in hematopoietic stem cells: a potential therapeutic approach for Fanconi anemia

Energy Technology Data Exchange (ETDEWEB)

Diez Cabezas, B.

2015-07-01

Gene therapy nowadays constitutes a safe and efficient treatment for a number of monogenic diseases affecting the hematopoietic system. Risks of insertional mutagenesis derived from the use of integrative vectors cannot, however, be completely excluded. Therefore, gene targeting has been proposed as a safer alternative, since the insertion of the herapeutic gene is driven to a specific locus in the genome. Gene targeting approaches are based on the use of specific nucleases which generate double strand breaks (DSBs) in a specific site of the genome,markedly enhancing the efficacy of homologous recombination (HR) with donor constructs harboring the gene of interest flanked by the corresponding homology arms. In this study we have optimized the conditions to target human lymphoblastic cell lines (LCLs) and also hematopoietic stem cells (HSCs) from healthy donors, with the final aim of correcting by gene editing the hematopoietic progenitor cells from Fanconi anemia subtype A (FA-A) patients. In particular, we have established a robust method to target both LCLs and HSCs in a safe harbor site in the genome, the AAVS1 locus. Our approach is based on the transduction of these cells with integrase-defective lentiviral vectors carrying a donor with the gene of interest, followed by the nucleofection of these cells with zinc finger nucleases used as mRNA. Using a control donor vector carrying the GFP reporter gene we have obtained, on average, 9.43% gene targeting efficiency in cord blood CD34+ cells from healthy donors. Moreover, we confirmed that gene targeting was also efficient in HSCs with long term and multipotent repopulation capacity, as demonstrated by transplants into immunodeficient mice. To improve the gene targeting efficiency, we investigated the feasibility of using gold nanoparticles, which were shown to improve the transduction efficiency of integrase-defective and competent lentiviral vectors in HSCs. This increment, however, did not lead to a higher gene

FAM20: an evolutionarily conserved family of secreted proteins expressed in hematopoietic cells

Directory of Open Access Journals (Sweden)

Cobos Everardo

2005-01-01

Full Text Available Abstract Background Hematopoiesis is a complex developmental process controlled by a large number of factors that regulate stem cell renewal, lineage commitment and differentiation. Secreted proteins, including the hematopoietic growth factors, play critical roles in these processes and have important biological and clinical significance. We have employed representational difference analysis to identify genes that are differentially expressed during experimentally induced myeloid differentiation in the murine EML hematopoietic stem cell line. Results One identified clone encoded a previously unidentified protein of 541 amino acids that contains an amino terminal signal sequence but no other characterized domains. This protein is a member of family of related proteins that has been named family with sequence similarity 20 (FAM20 with three members (FAM20A, FAM20B and FAM20C in mammals. Evolutionary comparisons revealed the existence of a single FAM20 gene in the simple vertebrate Ciona intestinalis and the invertebrate worm Caenorhabditis elegans and two genes in two insect species, Drosophila melanogaster and Anopheles gambiae. Six FAM20 family members were identified in the genome of the pufferfish, Fugu rubripes and five members in the zebrafish, Danio rerio. The mouse Fam20a protein was ectopically expressed in a mammalian cell line and found to be a bona fide secreted protein and efficient secretion was dependent on the integrity of the signal sequence. Expression analysis revealed that the Fam20a gene was indeed differentially expressed during hematopoietic differentiation and that the other two family members (Fam20b and Fam20c were also expressed during hematcpoiesis but that their mRNA levels did not vary significantly. Likewise FAM20A was expressed in more limited set of human tissues than the other two family members. Conclusions The FAM20 family represents a new family of secreted proteins with potential functions in regulating

In vivo engineering of bone tissues with hematopoietic functions and mixed chimerism.

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Shih, Yu-Ru; Kang, Heemin; Rao, Vikram; Chiu, Yu-Jui; Kwon, Seong Keun; Varghese, Shyni

2017-05-23

Synthetic biomimetic matrices with osteoconductivity and osteoinductivity have been developed to regenerate bone tissues. However, whether such systems harbor donor marrow in vivo and support mixed chimerism remains unknown. We devised a strategy to engineer bone tissues with a functional bone marrow (BM) compartment in vivo by using a synthetic biomaterial with spatially differing cues. Specifically, we have developed a synthetic matrix recapitulating the dual-compartment structures by modular assembly of mineralized and nonmineralized macroporous structures. Our results show that these matrices incorporated with BM cells or BM flush transplanted into recipient mice matured into functional bone displaying the cardinal features of both skeletal and hematopoietic compartments similar to native bone tissue. The hematopoietic function of bone tissues was demonstrated by its support for a higher percentage of mixed chimerism compared with i.v. injection and donor hematopoietic cell mobilization in the circulation of nonirradiated recipients. Furthermore, hematopoietic cells sorted from the engineered bone tissues reconstituted the hematopoietic system when transplanted into lethally irradiated secondary recipients. Such engineered bone tissues could potentially be used as ectopic BM surrogates for treatment of nonmalignant BM diseases and as a tool to study hematopoiesis, donor-host cell dynamics, tumor tropism, and hematopoietic cell transplantation.

Inquiry-Based Learning in Teacher Education: A Primary Humanities Example

Science.gov (United States)

Preston, Lou; Harvie, Kate; Wallace, Heather

2015-01-01

Inquiry-based learning features strongly in the new Australian Humanities and Social Sciences curriculum and increasingly in primary school practice. Yet, there is little research into, and few exemplars of, inquiry approaches in the primary humanities context. In this article, we outline and explain the implementation of a place-based simulation…

Analysis of glycoprotein E-selectin ligANDs on human and mouse marrow cells enriched for hematopoietic stem/progenitor cells

KAUST Repository

Merzaban, Jasmeen; Burdick, Monica M.; Gadhoum, Samah; Dagia, Nilesh M.; Chu, Julia T.; Fuhlbrigge, Robert C.; Sackstein, Robert D.

2011-01-01

Although well recognized that expression of E-selectin on marrow microvessels mediates osteotropism of hematopoietic stem/progenitor cells (HSPCs), our knowledge regarding the cognate E-selectin ligand(s) on HSPCs is incomplete. Flow cytometry using

Propagating Humanized BLT Mice for the Study of Human Immunology and Immunotherapy.

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Smith, Drake J; Lin, Levina J; Moon, Heesung; Pham, Alexander T; Wang, Xi; Liu, Siyuan; Ji, Sunjong; Rezek, Valerie; Shimizu, Saki; Ruiz, Marlene; Lam, Jennifer; Janzen, Deanna M; Memarzadeh, Sanaz; Kohn, Donald B; Zack, Jerome A; Kitchen, Scott G; An, Dong Sung; Yang, Lili

2016-12-15

The humanized bone marrow-liver-thymus (BLT) mouse model harbors a nearly complete human immune system, therefore providing a powerful tool to study human immunology and immunotherapy. However, its application is greatly limited by the restricted supply of human CD34 + hematopoietic stem cells and fetal thymus tissues that are needed to generate these mice. The restriction is especially significant for the study of human immune systems with special genetic traits, such as certain human leukocyte antigen (HLA) haplotypes or monogene deficiencies. To circumvent this critical limitation, we have developed a method to quickly propagate established BLT mice. Through secondary transfer of bone marrow cells and human thymus implants from BLT mice into NSG (NOD/SCID/IL-2Rγ -/- ) recipient mice, we were able to expand one primary BLT mouse into a colony of 4-5 proBLT (propagated BLT) mice in 6-8 weeks. These proBLT mice reconstituted human immune cells, including T cells, at levels comparable to those of their primary BLT donor mouse. They also faithfully inherited the human immune cell genetic traits from their donor BLT mouse, such as the HLA-A2 haplotype that is of special interest for studying HLA-A2-restricted human T cell immunotherapies. Moreover, an EGFP reporter gene engineered into the human immune system was stably passed from BLT to proBLT mice, making proBLT mice suitable for studying human immune cell gene therapy. This method provides an opportunity to overcome a critical hurdle to utilizing the BLT humanized mouse model and enables its more widespread use as a valuable preclinical research tool.

The transcriptional landscape of hematopoietic stem cell ontogeny

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McKinney-Freeman, Shannon; Cahan, Patrick; Li, Hu; Lacadie, Scott A.; Huang, Hsuan-Ting; Curran, Matthew; Loewer, Sabine; Naveiras, Olaia; Kathrein, Katie L.; Konantz, Martina; Langdon, Erin M.; Lengerke, Claudia; Zon, Leonard I.; Collins, James J.; Daley, George Q.

2012-01-01

Transcriptome analysis of adult hematopoietic stem cells (HSC) and their progeny has revealed mechanisms of blood differentiation and leukemogenesis, but a similar analysis of HSC development is lacking. Here, we acquired the transcriptomes of developing HSC purified from >2500 murine embryos and adult mice. We found that embryonic hematopoietic elements clustered into three distinct transcriptional states characteristic of the definitive yolk sac, HSCs undergoing specification, and definitive HSCs. We applied a network biology-based analysis to reconstruct the gene regulatory networks of sequential stages of HSC development and functionally validated candidate transcriptional regulators of HSC ontogeny by morpholino-mediated knock-down in zebrafish embryos. Moreover, we found that HSCs from in vitro differentiated embryonic stem cells closely resemble definitive HSC, yet lack a Notch-signaling signature, likely accounting for their defective lymphopoiesis. Our analysis and web resource (http://hsc.hms.harvard.edu) will enhance efforts to identify regulators of HSC ontogeny and facilitate the engineering of hematopoietic specification. PMID:23122293

Aging of hematopoietic stem cells : Intrinsic changes or micro-environmental effects?

NARCIS (Netherlands)

Woolthuis, Carolien M.; de Haan, Gerald; Huls, Gerwin

During development hematopoietic stem cells (HSCs) expand in number and persist throughout life by undergoing self-renewing divisions. Nevertheless, the hematopoietic system does not escape the negative effects of aging, suggesting that self-renewal is not complete. A fundamental issue in stem cell

An in vitro model of hemogenic endothelium commitment and hematopoietic production

NARCIS (Netherlands)

Yvernogeau, Laurent; Gautier, Rodolphe; Khoury, Hanane; Menegatti, Sara; Schmidt, Melanie; Gilles, Jean Francois; Jaffredo, Thierry

2016-01-01

Adult-type hematopoietic stem and progenitor cells are formed during ontogeny from a specialized subset of endothelium, termed the hemogenic endothelium, via an endothelial-to-hematopoietic transition (EHT) that occurs in the embryonic aorta and the associated arteries. Despite efforts to generate

Integrative analysis of copy number and gene expression data suggests novel pathogenetic mechanisms in primary myelofibrosis.

Science.gov (United States)

Salati, Simona; Zini, Roberta; Nuzzo, Simona; Guglielmelli, Paola; Pennucci, Valentina; Prudente, Zelia; Ruberti, Samantha; Rontauroli, Sebastiano; Norfo, Ruggiero; Bianchi, Elisa; Bogani, Costanza; Rotunno, Giada; Fanelli, Tiziana; Mannarelli, Carmela; Rosti, Vittorio; Salmoiraghi, Silvia; Pietra, Daniela; Ferrari, Sergio; Barosi, Giovanni; Rambaldi, Alessandro; Cazzola, Mario; Bicciato, Silvio; Tagliafico, Enrico; Vannucchi, Alessandro M; Manfredini, Rossella

2016-04-01

Primary myelofibrosis (PMF) is a Myeloproliferative Neoplasm (MPN) characterized by megakaryocyte hyperplasia, progressive bone marrow fibrosis, extramedullary hematopoiesis and transformation to Acute Myeloid Leukemia (AML). A number of phenotypic driver (JAK2, CALR, MPL) and additional subclonal mutations have been described in PMF, pointing to a complex genomic landscape. To discover novel genomic lesions that can contribute to disease phenotype and/or development, gene expression and copy number signals were integrated and several genomic abnormalities leading to a concordant alteration in gene expression levels were identified. In particular, copy number gain in the polyamine oxidase (PAOX) gene locus was accompanied by a coordinated transcriptional up-regulation in PMF patients. PAOX inhibition resulted in rapid cell death of PMF progenitor cells, while sparing normal cells, suggesting that PAOX inhibition could represent a therapeutic strategy to selectively target PMF cells without affecting normal hematopoietic cells' survival. Moreover, copy number loss in the chromatin modifier HMGXB4 gene correlates with a concomitant transcriptional down-regulation in PMF patients. Interestingly, silencing of HMGXB4 induces megakaryocyte differentiation, while inhibiting erythroid development, in human hematopoietic stem/progenitor cells. These results highlight a previously un-reported, yet potentially interesting role of HMGXB4 in the hematopoietic system and suggest that genomic and transcriptional imbalances of HMGXB4 could contribute to the aberrant expansion of the megakaryocytic lineage that characterizes PMF patients. © 2015 UICC.

Differentiation stage-specific regulation of primitive human hematopoietic progenitor cycling by exogenous and endogenous inhibitors in an in vivo model.

Science.gov (United States)

Cashman, J D; Clark-Lewis, I; Eaves, A C; Eaves, C J

1999-12-01

Nonobese diabetic/severe combined immunodeficient (NOD/SCID) mice transplanted with human cord blood or adult marrow cells and injected 6 weeks posttransplant with 2 daily doses of transforming growth factor-beta(1) (TGF-beta(1)), monocyte chemoattractant protein-1 (MCP-1), or a nonaggregating form of macrophage inflammatory protein-1alpha (MIP-1alpha) showed unique patterns of inhibition of human progenitor proliferation 1 day later. TGF-beta(1) was active on long-term culture initiating cells (LTC-IC) and on primitive erythroid and granulopoietic colony-forming cells (HPP-CFC), but had no effect on mature CFC. MCP-1 inhibited the cycling of both types of HPP-CFC but not LTC-IC. MIP-1alpha did not inhibit either LTC-IC or granulopoietic HPP-CFC but was active on erythroid HPP-CFC and mature granulopoietic CFC. All of these responses were independent of the source of human cells transplanted. LTC-IC of either human cord blood or adult marrow origin continue to proliferate in NOD/SCID mice for many weeks, although the turnover of all types of human CFC in mice transplanted with adult human marrow (but not cord blood) is downregulated after 6 weeks. Interestingly, administration of either MIP-1beta, an antagonist of both MIP-1alpha and MCP-1 or MCP-1(9-76), an antagonist of MCP-1 (and MCP-2 and MCP-3), into mice in which human marrow-derived CFC had become quiescent, caused the rapid reactivation of these progenitors in vivo. These results provide the first definition of stage-specific inhibitors of human hematopoietic progenitor cell cycling in vivo. In addition they show that endogenous chemokines can contribute to late graft failure, which can be reversed by the administration of specific antagonists.

Effect of cotransplantation of hematopoietic stem cells and embryonic AGM stromal cells on hematopoietic reconstitution in mice after bone marrow transplantation

International Nuclear Information System (INIS)

Tao Si; Sun Hanying; Liu Wenli

2007-01-01

Objective: To explore the effects of cotransplantation of hematopoietic stem cells and stromal cells derived from aorta-gonad-mesonephros (AGM) region on hematopoietic reconstitution in mice after bone marrow transplantation (BMT). Methods: The typical mice model of syngeneic BMT was established and the mice were randomly divided into 4 groups: the control group, the BMT group, the group of cotransplantation of HSC with AGM stromal cells (the cotransplantation group) and the ligustrazine group (the LT group). On days 3, 7, 10, 14, 21 and 28 after BMT, the peripheral blood cells and bone marrow mononuclear cells (BMMNC) were counted, and histology changes of bone marrow were detected. Results: The levels of peripheral WBC, RBC, platelet, and BMMNC in the contransplantation group were significantly higher than those in the single BMT group and the LT group (P<0.05). Conclusions: Cotransplantation with AGM stromal cells could significantly promote hematopoietic reconstruction in mice after BMT. (authors)

Studies on mechanism of treatment of granulocyte colony-stimulating factor, recombinant human interleukin-11 and recombinant human interleukin-2 on hematopoietic injuries induced by 4.5 Gy γ-rays irradiation in beagles

International Nuclear Information System (INIS)

Li Ming; Ou Hongling; Xing Shuang; Huang Haixiao; Xiong Guolin; Xie Ling; Zhao Yanfang; Zhao Zhenhu; Wang Ning; Wang Jinxiang; Miao Jingcheng; Zhu Nankang; Luo Qingliang; Cong Yuwen; Zhang Xueguang

2010-01-01

Objective: To investigate the mechanism of treatment of granulocyte colony-stimulating factor (rhG-CSF), recombinant human interleukin-11 (rhIL-11) and recombinant human interleukin-2 (rhIL-2) on hematopoietic injuries induced by 4.5 Gy 60 Co γ-ray irradiation in beagles, and to provide experimental evidence for the clinical treatment of extremely severe myeloid acute radiation sickness (ARS). Methods: Sixteen beagle dogs were given 4.5 Gy 60 Co γ-ray total body irradiation (TBI), then randomly assigned into irradiation control group, supportive care group or cytokines + supportive care (abbreviated as cytokines) group. In addition to supportive care, rhG-CSF, rhIL-11 and rhIL-2 were administered subcutaneously to treat dogs in cytokines group. The percentage of CD34 + cells, cell cycle and apoptosis of nucleated cells in peripheral blood were examined by Flow cytometry. Results: After 4.5 Gy 60 Co γ-ray irradiation, the CD34 + cells in peripheral blood declined obviously (61.3% and 52.1% of baseline for irradiation control and supportive care group separately). The cell proportion of nucleated cells in G 0 /G 1 phase was increased notably notably (99.27% and 99.49% respectively). The rate of apoptosis (26.93% and 21.29% separately) and necrosis (3.27% and 4.14%, respectively) of nucleated cells were elevated significantly when compared with values before irradiation (P 0 /G 1 phase blockage of nucleated cells became more serious (99.71%). The rate of apoptosis (5.66%) and necrosis (1.60%) of nucleated cells were significantly lower than that of irradiation control and supportive care groups 1 d after exposure. Conclusions: Cytokines maybe mobilize CD34 + cells in bone marrow to peripheral blood, indce cell block at G 0 /G 1 phase and reduce apoptosis, and eventually cure hematopoietic injuries induced by irradiation. (authors)

Icing oral mucositis: Oral cryotherapy in multiple myeloma patients undergoing autologous hematopoietic stem cell transplant.

Science.gov (United States)

Chen, Joey; Seabrook, Jamie; Fulford, Adrienne; Rajakumar, Irina

2017-03-01

Background Up to 70% of patients receiving hematopoietic stem cell transplant develop oral mucositis as a side effect of high-dose melphalan conditioning chemotherapy. Oral cryotherapy has been documented to be potentially effective in reducing oral mucositis. The aim of this study was to examine the effectiveness of the cryotherapy protocol implemented within the hematopoietic stem cell transplant program. Methods A retrospective chart review was conducted of adult multiple myeloma patients who received high-dose melphalan conditioning therapy for autologous hematopoietic stem cell transplant. Primary endpoints were incidence and severity of oral mucositis. Secondary endpoints included duration of oral mucositis, duration of hospital stay, parenteral narcotics use and total parenteral nutrition use. Results One hundred and forty patients were included in the study, 70 patients in both no cryotherapy and cryotherapy groups. Both oral mucositis incidence and severity were found to be significantly lower in the cryotherapy group. Fifty (71.4%) experienced mucositis post cryotherapy compared to 67 (95.7%) in the no cryotherapy group (p cryotherapy group (p = 0.03). Oral mucositis duration and use of parenteral narcotics were also significantly reduced. Duration of hospital stay and use of parenteral nutrition were similar between the two groups. Conclusion The cryotherapy protocol resulted in a significantly lower incidence and severity of oral mucositis. These results provide evidence for the continued use of oral cryotherapy, an inexpensive and generally well-tolerated practice.

Cord blood hematopoietic cells from preterm infants display altered DNA methylation patterns.

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de Goede, Olivia M; Lavoie, Pascal M; Robinson, Wendy P

2017-01-01

Premature infants are highly vulnerable to infection. This is partly attributable to the preterm immune system, which differs from that of the term neonate in cell composition and function. Multiple studies have found differential DNA methylation (DNAm) between preterm and term infants' cord blood; however, interpretation of these studies is limited by the confounding factor of blood cell composition. This study evaluates the epigenetic impact of preterm birth in isolated hematopoietic cell populations, reducing the concern of cell composition differences. Genome-wide DNAm was measured using the Illumina 450K array in T cells, monocytes, granulocytes, and nucleated red blood cells (nRBCs) isolated from cord blood of 5 term and 5 preterm (blood cells (nRBCs) showed the most extensive changes in DNAm, with 9258 differentially methylated (DM) sites (FDR  0.10) discovered between preterm and term infants compared to the blood cell populations. The direction of DNAm change with gestational age at these prematurity-DM sites followed known patterns of hematopoietic differentiation, suggesting that term hematopoietic cell populations are more epigenetically mature than their preterm counterparts. Consistent shifts in DNAm between preterm and term cells were observed at 25 CpG sites, with many of these sites located in genes involved in growth and proliferation, hematopoietic lineage commitment, and the cytoskeleton. DNAm in preterm and term hematopoietic cells conformed to previously identified DNAm signatures of fetal liver and bone marrow, respectively. This study presents the first genome-wide mapping of epigenetic differences in hematopoietic cells across the late gestational period. DNAm differences in hematopoietic cells between term and <31 weeks were consistent with the hematopoietic origin of these cells during ontogeny, reflecting an important role of DNAm in their regulation. Due to the limited sample size and the high coincidence of prematurity and

Two hemocyte lineages exist in silkworm larval hematopoietic organ.

Science.gov (United States)

Nakahara, Yuichi; Kanamori, Yasushi; Kiuchi, Makoto; Kamimura, Manabu

2010-07-28

Insects have multiple hemocyte morphotypes with different functions as do vertebrates, however, their hematopoietic lineages are largely unexplored with the exception of Drosophila melanogaster. To study the hematopoietic lineage of the silkworm, Bombyx mori, we investigated in vivo and in vitro differentiation of hemocyte precursors in the hematopoietic organ (HPO) into the four mature hemocyte subsets, namely, plasmatocytes, granulocytes, oenocytoids, and spherulocytes. Five days after implantation of enzymatically-dispersed HPO cells from a GFP-expressing transgenic line into the hemocoel of normal larvae, differentiation into plasmatocytes, granulocytes and oenocytoids, but not spherulocytes, was observed. When the HPO cells were cultured in vitro, plasmatocytes appeared rapidly, and oenocytoids possessing prophenol oxidase activity appeared several days later. HPO cells were also able to differentiate into a small number of granulocytes, but not into spherulocytes. When functionally mature plasmatocytes were cultured in vitro, oenocytoids were observed 10 days later. These results suggest that the hemocyte precursors in HPO first differentiate into plasmatocytes, which further change into oenocytoids. From these results, we propose that B. mori hemocytes can be divided into two major lineages, a granulocyte lineage and a plasmatocyte-oenocytoid lineage. The origins of the spherulocytes could not be determined in this study. We construct a model for the hematopoietic lineages at the larval stage of B. mori.

In Utero Hematopoietic Cell Transplantation for Hemoglobinopathies

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Tippi C. Mackenzie

2015-01-01

Full Text Available In utero hematopoietic cell transplantation (IUHCTx is a promising strategy to circumvent the challenges of postnatal hematopoietic stem cell (HSC transplantation. The goal of IUHCTx is to introduce donor cells into a naïve host prior to immune maturation, thereby inducing donor–specific tolerance. Thus, this technique has the potential of avoiding host myeloablative conditioning with cytotoxic agents. Over the past two decades, several attempts at IUHCTx have been made to cure numerous underlying congenital anomalies with limited success. In this review, we will briefly review the history of IUHCTx and give a perspective on alpha thalassemia major, one target disease for its clinical application.

Immunoglobulin lambda light chain gene rearrangements in human B-cell malignancies

NARCIS (Netherlands)

T. Tümkaya (Talip)

1997-01-01

textabstractLymphocytes form the specific immune system, capable of recognizing and responding to any foreign antigen, while remaining indifferent to self components. Throughout human life, lymphocytes are continuously generated from pluripotent hematopoietic stem cells. These hematopoietic stem

Hematopoietic stem cell transplantation monitoring in childhood. Hematological diseases in Serbia: STR-PCR techniques

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Krstić Aleksandra D.

2007-01-01

Full Text Available Hematopoietic stem cell transplantation (HSCT is a very successful method of treatment for children with different aquired or inborn diseases. The main goal of post-transplantation chimerism monitoring in HSCT is to predict negative events (such as disease relapse and graft rejection, in order to intervene with appropriate therapy and improve the probability of long-term DFS (disease free survival. In this context, by quantifying the relative amounts of donor and recipient cells present in the peripheral blood sample, it can be determined if engraftment has taken place at all, or if full or mixed chimerism exists. In a group of patients who underwent hematopoietic stem cell transplantation at the Mother and Child Health Care Institute, we decided to use standard human identfication tests based on multiplex PCR analyses of short tandem repeats (STRs, as they are highly informative, sensitive, and fast and therefore represent an optimal methodological approach to engraftment analysis.

Effects of hematopoietic growth factors on purified bone marrow progenitor cells

NARCIS (Netherlands)

F.J. Bot (Freek)

1992-01-01

textabstractWe have used highly enriched hematopoietic progenitor cells and in-vitro culture to examine the following questions: 1. The effects of recombinant lL-3 and GM-CSF on proliferation and differentiation of enriched hematopoietic progenitor cells have not been clearly defined: - how do IL~3

Role of HLA in Hematopoietic Stem Cell Transplantation

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Meerim Park

2012-01-01

Full Text Available The selection of hematopoietic stem cell transplantation (HSCT donors includes a rigorous assessment of the availability and human leukocyte antigen (HLA match status of donors. HLA plays a critical role in HSCT, but its involvement in HSCT is constantly in flux because of changing technologies and variations in clinical transplantation results. The increased availability of HSCT through the use of HLA-mismatched related and unrelated donors is feasible with a more complete understanding of permissible HLA mismatches and the role of killer-cell immunoglobulin-like receptor (KIR genes in HSCT. The influence of nongenetic factors on the tolerability of HLA mismatching has recently become evident, demonstrating a need for the integration of both genetic and nongenetic variables in donor selection.

Therapeutic effects of combined cytokines on hematopoietic injuries induced by 4.5 Gy γ-rays irradiation in beagles

International Nuclear Information System (INIS)

Zhao Jianzhi; Li Ming; Xing Shuang; Hu Zhiqing; Xiong Guolin; Xie Ling; Ou Hongling; Huang Haixiao; Zhao Zhenhu; Wang Ning; Wang Jinxiang; Miao Jingcheng; Zhu Nankang; Zhang Xueguang; Cong Yuwen; Zhang Ri; Luo Qingliang

2010-01-01

Objective: To observe the therapeutic effects of combined cytokines on hematopoietic injuries induced by 4.5 Gy 60 Co γ-rays irradiation in beagles, and to provide experimental evidences for the clinical treatment of extremely severe myeloid acute radiation sickness (ARS). Methods: 16 beagles were given 4.5 Gy 60 Co γ-rays total body irradiation, and then randomly assigned into irradiation control group, supportive care group and cytokines group. In addition to supportive care, recombinant human granulocyte colony-stimulating factor (rhG-CSF), recombinant human interleukin-11 (rhIL-11) and recombinant human interleukin-2 (rhIL-2) were administered subcutaneouly to dogs in cytokines group. Peripheral blood hemogram was examined once every two days. Bone marrow and peripheral blood were collected to proceed colony cultivation 4 d pre-irradiation and 1 and 45 d post-irradiation. Conventional histopathological sections sternum were prepared to observe the histomorphology changes. Results: After irradiation, the population of all kinds of cells in peripheral blood declined sharply. WBC nadir was elevated (1.04 x 10 9 /L, but 0.28 x 10 9 /L and 0.68 x 10 9 /L for the irradiation control group and the supportive care group separately), the duration of thrombocytopenia was shortened (24 days, but 33 days for the supportive care group) and red blood cell counts were maintained in the range of normal values after cytokines treatment in combination. The colony forming efficiency of haemopoietic stem cells (HSCs) in bone marrow and peripheral blood decreased obviously 1 d post irradiation, but recovered to the level of that before irradiation 45 d post irradiation after supportive care and cytokines treatment. Hematopoietic cells disappeared in bone marrow of animals in irradiation control group, but hematopoietic functions were recovered after cytokines were administrated. Conclusions: RhG-CSF, rhIL-11 and rhIL-2 used in combination could elevate WBC nadir, accelerate the

Hematopoietic Gene Therapies for Metabolic and Neurologic Diseases.

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Biffi, Alessandra

2017-10-01

Increasingly, patients affected by metabolic diseases affecting the central nervous system and neuroinflammatory disorders receive hematopoietic cell transplantation (HCT) in the attempt to slow the course of their disease, delay or attenuate symptoms, and improve pathologic findings. The possible replacement of brain-resident myeloid cells by the transplanted cell progeny contributes to clinical benefit. Genetic engineering of the cells to be transplanted (hematopoietic stem cell) may endow the brain myeloid progeny of these cells with enhanced or novel functions, contributing to therapeutic effects. Copyright © 2017 Elsevier Inc. All rights reserved.

Reconstituting development of pancreatic intraepithelial neoplasia from primary human pancreas duct cells

OpenAIRE

Lee, Jonghyeob; Snyder, Emily R.; Liu, Yinghua; Gu, Xueying; Wang, Jing; Flowers, Brittany M.; Kim, Yoo Jung; Park, Sangbin; Szot, Gregory L.; Hruban, Ralph H.; Longacre, Teri A.; Kim, Seung K.

2017-01-01

Development of systems that reconstitute hallmark features of human pancreatic intraepithelial neoplasia (PanINs), the precursor to pancreatic ductal adenocarcinoma, could generate new strategies for early diagnosis and intervention. However, human cell-based PanIN models with defined mutations are unavailable. Here, we report that genetic modification of primary human pancreatic cells leads to development of lesions resembling native human PanINs. Primary human pancreas duct cells harbouring...

Engineered matrix coatings to modulate the adhesion of CD133+ human hematopoietic progenitor cells.

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Franke, Katja; Pompe, Tilo; Bornhäuser, Martin; Werner, Carsten

2007-02-01

Interactions of hematopoietic progenitor cells (HPC) with their local microenvironments in the bone marrow are thought to control homing, differentiation, and self-renewal of the cells. To dissect the role of extracellular matrix (ECM) components of the niche microenvironment, a set of well-defined ECM coatings including fibronectin, heparin, heparan sulphate, hyaluronic acid, tropocollagen I, and co-fibrils of collagen I with heparin or hyaluronic acid was prepared and analysed with respect to the attachment of human CD133+ HPC in vitro. The extension of the adhesion areas of individual cells as well as the fraction of adherent cells were assessed by reflection interference contrast microscopy (RICM). Intense cell-matrix interactions were found on surfaces coated with fibronectin, heparin, heparan sulphate, and on the collagen I based co-fibrils. Insignificant adhesion was found for tropocollagen I and hyaluronic acid. The strongest adhesion of HPC was observed on fibronectin with contact areas of about 7 microm(2). Interaction of HPC with coatings consisting of heparin, heparan sulphate, and co-fibrils result in small circular shaped contact zones of 3 microm(2) pointing to another, less efficient, adhesion mechanism. Analysing the specificity of cell-matrix interaction by antibody blocking experiments suggests an integrin(alpha(5)beta(1))-specific adhesion on fibronectin, while adhesion on heparin was shown to be mediated by selectins (CD62L). Taken together, our data provide a basis for the design of advanced culture carriers supporting site-specific proliferation or differentiation of HPC.

Milestones of Hematopoietic Stem Cell Transplantation – From First Human Studies to Current Developments

Science.gov (United States)

Juric, Mateja Kralj; Ghimire, Sakhila; Ogonek, Justyna; Weissinger, Eva M.; Holler, Ernst; van Rood, Jon J.; Oudshoorn, Machteld; Dickinson, Anne; Greinix, Hildegard T.

2016-01-01

Since the early beginnings, in the 1950s, hematopoietic stem cell transplantation (HSCT) has become an established curative treatment for an increasing number of patients with life-threatening hematological, oncological, hereditary, and immunological diseases. This has become possible due to worldwide efforts of preclinical and clinical research focusing on issues of transplant immunology, reduction of transplant-associated morbidity, and mortality and efficient malignant disease eradication. The latter has been accomplished by potent graft-versus-leukemia (GvL) effector cells contained in the stem cell graft. Exciting insights into the genetics of the human leukocyte antigen (HLA) system allowed improved donor selection, including HLA-identical related and unrelated donors. Besides bone marrow, other stem cell sources like granulocyte-colony stimulating-mobilized peripheral blood stem cells and cord blood stem cells have been established in clinical routine. Use of reduced-intensity or non-myeloablative conditioning regimens has been associated with a marked reduction of non-hematological toxicities and eventually, non-relapse mortality allowing older patients and individuals with comorbidities to undergo allogeneic HSCT and to benefit from GvL or antitumor effects. Whereas in the early years, malignant disease eradication by high-dose chemotherapy or radiotherapy was the ultimate goal; nowadays, allogeneic HSCT has been recognized as cellular immunotherapy relying prominently on immune mechanisms and to a lesser extent on non-specific direct cellular toxicity. This chapter will summarize the key milestones of HSCT and introduce current developments. PMID:27881982

Preservation of differentiation and clonogenic potential of human hematopoietic stem and progenitor cells during lyophilization and ambient storage.

Science.gov (United States)

Buchanan, Sandhya S; Pyatt, David W; Carpenter, John F

2010-09-01

Progenitor cell therapies show great promise, but their potential for clinical applications requires improved storage and transportation. Desiccated cells stored at ambient temperature would provide economic and practical advantages over approaches employing cell freezing and subzero temperature storage. The objectives of this study were to assess a method for loading the stabilizing sugar, trehalose, into hematopoietic stem and progenitor cells (HPC) and to evaluate the effects of subsequent freeze-drying and storage at ambient temperature on differentiation and clonogenic potential. HPC were isolated from human umbilical cord blood and loaded with trehalose using an endogenous cell surface receptor, termed P2Z. Solution containing trehalose-loaded HPC was placed into vials, which were transferred to a tray freeze-dryer and removed during each step of the freeze-drying process to assess differentiation and clonogenic potential. Control groups for these experiments were freshly isolated HPC. Control cells formed 1450+/-230 CFU-GM, 430+/-140 BFU-E, and 50+/-40 CFU-GEMM per 50 microL. Compared to the values for the control cells, there was no statistical difference observed for cells removed at the end of the freezing step or at the end of primary drying. There was a gradual decrease in the number of CFU-GM and BFU-E for cells removed at different temperatures during secondary drying; however, there were no significant differences in the number of CFU-GEMM. To determine storage stability of lyophilized HPC, cells were stored for 4 weeks at 25 degrees C in the dark. Cells reconstituted immediately after lyophilization produced 580+/-90 CFU-GM ( approximately 40%, relative to unprocessed controls pGM (approximately 35%, relative to unprocessed controls, p<0.0001), 112+/-68 BFU-E (approximately 26%, p<0.0001), and 36+/-17 CFU-GEMM ( approximately 82%, p = 0.2164) These studies are the first to document high level retention of CFU-GEMM following lyophilization and

Forkhead Box C1 Regulates Human Primary Keratinocyte Terminal Differentiation.

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Lianghua Bin

Full Text Available The epidermis serves as a critical protective barrier between the internal and external environment of the human body. Its remarkable barrier function is established through the keratinocyte (KC terminal differentiation program. The transcription factors specifically regulating terminal differentiation remain largely unknown. Using a RNA-sequencing (RNA-seq profiling approach, we found that forkhead box c 1 (FOXC1 was significantly up-regulated in human normal primary KC during the course of differentiation. This observation was validated in human normal primary KC from several different donors and human skin biopsies. Silencing FOXC1 in human normal primary KC undergoing differentiation led to significant down-regulation of late terminal differentiation genes markers including epidermal differentiation complex genes, keratinization genes, sphingolipid/ceramide metabolic process genes and epidermal specific cell-cell adhesion genes. We further demonstrated that FOXC1 works down-stream of ZNF750 and KLF4, and upstream of GRHL3. Thus, this study defines FOXC1 as a regulator specific for KC terminal differentiation and establishes its potential position in the genetic regulatory network.

Long-term culture and expansion of primary human hepatocytes

NARCIS (Netherlands)

Levy, G.; Bomze, D.; Heinz, S.; Ramachandran, S.D.; Noerenberg, A.; Cohen, M.; Shibolet, O.; Sklan, E.; Braspenning, J.C.; Nahmias, Y.

2015-01-01

Hepatocytes have a critical role in metabolism, but their study is limited by the inability to expand primary hepatocytes in vitro while maintaining proliferative capacity and metabolic function. Here we describe the oncostatin M (OSM)-dependent expansion of primary human hepatocytes by low

β-Arrestin2 mediates progression of murine primary myelofibrosis.

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Rein, Lindsay Am; Wisler, James W; Kim, Jihee; Theriot, Barbara; Huang, LiYin; Price, Trevor; Yang, Haeyoon; Chen, Minyong; Chen, Wei; Sipkins, Dorothy; Fedoriw, Yuri; Walker, Julia Kl; Premont, Richard T; Lefkowitz, Robert J

2017-12-21

Primary myelofibrosis is a myeloproliferative neoplasm associated with significant morbidity and mortality, for which effective therapies are lacking. β-Arrestins are multifunctional adaptor proteins involved in developmental signaling pathways. One isoform, β-arrestin2 (βarr2), has been implicated in initiation and progression of chronic myeloid leukemia, another myeloproliferative neoplasm closely related to primary myelofibrosis. Accordingly, we investigated the relationship between βarr2 and primary myelofibrosis. In a murine model of MPLW515L-mutant primary myelofibrosis, mice transplanted with donor βarr2-knockout (βarr2-/-) hematopoietic stem cells infected with MPL-mutant retrovirus did not develop myelofibrosis, whereas controls uniformly succumbed to disease. Although transplanted βarr2-/- cells homed properly to marrow, they did not repopulate long-term due to increased apoptosis and decreased self-renewal of βarr2-/- cells. In order to assess the effect of acute loss of βarr2 in established primary myelofibrosis in vivo, we utilized a tamoxifen-induced Cre-conditional βarr2-knockout mouse. Mice that received Cre (+) donor cells and developed myelofibrosis had significantly improved survival compared with controls. These data indicate that lack of antiapoptotic βarr2 mediates marrow failure of murine hematopoietic stem cells overexpressing MPLW515L. They also indicate that βarr2 is necessary for progression of primary myelofibrosis, suggesting that it may serve as a novel therapeutic target in this disease.

Activated H-Ras regulates hematopoietic cell survival by modulating Survivin

International Nuclear Information System (INIS)

Fukuda, Seiji; Pelus, Louis M.

2004-01-01

Survivin expression and Ras activation are regulated by hematopoietic growth factors. We investigated whether activated Ras could circumvent growth factor-regulated Survivin expression and if a Ras/Survivin axis mediates growth factor independent survival and proliferation in hematopoietic cells. Survivin expression is up-regulated by IL-3 in Ba/F3 and CD34 + cells and inhibited by the Ras inhibitor, farnesylthiosalicylic acid. Over-expression of constitutively activated H-Ras (CA-Ras) in Ba/F3 cells blocked down-modulation of Survivin expression, G 0 /G 1 arrest, and apoptosis induced by IL-3 withdrawal, while dominant-negative (DN) H-Ras down-regulated Survivin. Survivin disruption by DN T34A Survivin blocked CA-Ras-induced IL-3-independent cell survival and proliferation; however, it did not affect CA-Ras-mediated enhancement of S-phase, indicating that the anti-apoptotic activity of CA-Ras is Survivin dependent while its S-phase enhancing effect is not. These results indicate that CA-Ras modulates Survivin expression independent of hematopoietic growth factors and that a CA-Ras/Survivin axis regulates survival and proliferation of transformed hematopoietic cells

Autologous Hematopoietic Stem Cell Transplantation to Prevent Antibody Mediated Rejection After Vascularized Composite Allotransplantation

Science.gov (United States)

2017-10-01

Award Number: W81XWH-16-1-0664 TITLE: Autologous Hematopoietic Stem Cell Transplantation to Prevent Antibody-Mediated Rejection after...Annual 3. DATES COVERED 15 Sep 2016 – 14 Sep 2017 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Autologous Hematopoietic Stem Cell Transplantation to...sensitization, autologous hematopoietic stem cell transplantation, antibody mediated rejection, donor specific antibodies 16. SECURITY CLASSIFICATION OF

STAT5-mediated self-renewal of normal hematopoietic and leukemic stem cells

NARCIS (Netherlands)

Schepers, Hein; Wierenga, Albertus T. J.; Vellenga, Edo; Schuringa, Jan Jacob

2012-01-01

The level of transcription factor activity critically regulates cell fate decisions such as hematopoietic stem cell self-renewal and differentiation. The balance between hematopoietic stem cell self-renewal and differentiation needs to be tightly controlled, as a shift toward differentiation might

Mutual Interference between Cytomegalovirus and Reconstitution of Protective Immunity after Hematopoietic Cell Transplantation

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Matthias J. Reddehase

2016-08-01

Full Text Available Hematopoietic cell transplantation (HCT is a therapy option for aggressive forms of hematopoietic malignancies that are resistant to standard antitumoral therapies. Hematoablative treatment preceding HCT, however, opens a ‘window of opportunity’ for latent cytomegalovirus (CMV by releasing it from immune control with the consequence of reactivation of productive viral gene expression and recurrence of infectious virus. A ‘window of opportunity’ for the virus represents a ‘window of risk’ for the patient. In the interim between HCT and reconstitution of antiviral immunity, primarily mediated by CD8+ T cells, initially low amounts of reactivated virus can expand exponentially, disseminate to essentially all organs, and cause multiple organ CMV disease, with interstitial pneumonia (CMV-IP representing the most severe clinical manifestation. Here I will review predictions originally made in the mouse model of experimental HCT and murine CMV infection, some of which have already paved the way to translational preclinical research and promising clinical trials of a pre-emptive cytoimmunotherapy of human CMV disease. Specifically, the mouse model has been pivotal in providing ‘proof of concept’ for preventing CMV disease after HCT by adoptive transfer of preselected, virus epitope-specific effector and memory CD8+ T cells bridging the critical interim. CMV, however, is not a ‘passive antigen’ but is a pathogen that actively interferes with the reconstitution of protective immunity by infecting bone marrow stromal cells that otherwise form niches for hematopoiesis by providing the structural microenvironment and by producing hematopoietically active cytokines, the hemopoietins. Depending on the precise conditions of HCT, reduced homing of transplanted hematopoietic stem- and progenitor cells to infected bone marrow stroma and impaired colony growth and lineage differentiation can lead to ‘graft failure’. In consequence

Reticular dysgenesis–associated AK2 protects hematopoietic stem and progenitor cell development from oxidative stress

Science.gov (United States)

Rissone, Alberto; Weinacht, Katja Gabriele; la Marca, Giancarlo; Bishop, Kevin; Giocaliere, Elisa; Jagadeesh, Jayashree; Felgentreff, Kerstin; Dobbs, Kerry; Al-Herz, Waleed; Jones, Marypat; Chandrasekharappa, Settara; Kirby, Martha; Wincovitch, Stephen; Simon, Karen Lyn; Itan, Yuval; DeVine, Alex; Schlaeger, Thorsten; Schambach, Axel; Sood, Raman

2015-01-01

Adenylate kinases (AKs) are phosphotransferases that regulate the cellular adenine nucleotide composition and play a critical role in the energy homeostasis of all tissues. The AK2 isoenzyme is expressed in the mitochondrial intermembrane space and is mutated in reticular dysgenesis (RD), a rare form of severe combined immunodeficiency (SCID) in humans. RD is characterized by a maturation arrest in the myeloid and lymphoid lineages, leading to early onset, recurrent, and overwhelming infections. To gain insight into the pathophysiology of RD, we studied the effects of AK2 deficiency using the zebrafish model and induced pluripotent stem cells (iPSCs) derived from fibroblasts of an RD patient. In zebrafish, Ak2 deficiency affected hematopoietic stem and progenitor cell (HSPC) development with increased oxidative stress and apoptosis. AK2-deficient iPSCs recapitulated the characteristic myeloid maturation arrest at the promyelocyte stage and demonstrated an increased AMP/ADP ratio, indicative of an energy-depleted adenine nucleotide profile. Antioxidant treatment rescued the hematopoietic phenotypes in vivo in ak2 mutant zebrafish and restored differentiation of AK2-deficient iPSCs into mature granulocytes. Our results link hematopoietic cell fate in AK2 deficiency to cellular energy depletion and increased oxidative stress. This points to the potential use of antioxidants as a supportive therapeutic modality for patients with RD. PMID:26150473

Two hemocyte lineages exist in silkworm larval hematopoietic organ.

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Yuichi Nakahara

Full Text Available BACKGROUND: Insects have multiple hemocyte morphotypes with different functions as do vertebrates, however, their hematopoietic lineages are largely unexplored with the exception of Drosophila melanogaster. METHODOLOGY/PRINCIPAL FINDINGS: To study the hematopoietic lineage of the silkworm, Bombyx mori, we investigated in vivo and in vitro differentiation of hemocyte precursors in the hematopoietic organ (HPO into the four mature hemocyte subsets, namely, plasmatocytes, granulocytes, oenocytoids, and spherulocytes. Five days after implantation of enzymatically-dispersed HPO cells from a GFP-expressing transgenic line into the hemocoel of normal larvae, differentiation into plasmatocytes, granulocytes and oenocytoids, but not spherulocytes, was observed. When the HPO cells were cultured in vitro, plasmatocytes appeared rapidly, and oenocytoids possessing prophenol oxidase activity appeared several days later. HPO cells were also able to differentiate into a small number of granulocytes, but not into spherulocytes. When functionally mature plasmatocytes were cultured in vitro, oenocytoids were observed 10 days later. These results suggest that the hemocyte precursors in HPO first differentiate into plasmatocytes, which further change into oenocytoids. CONCLUSIONS/SIGNIFICANCE: From these results, we propose that B. mori hemocytes can be divided into two major lineages, a granulocyte lineage and a plasmatocyte-oenocytoid lineage. The origins of the spherulocytes could not be determined in this study. We construct a model for the hematopoietic lineages at the larval stage of B. mori.

Therapeutic approaches of hematopoietic syndrome after serious accidental global irradiation. Ex vivo expansion interest of hematopoietic cells

International Nuclear Information System (INIS)

Thierry, D.

1994-01-01

Aplasia is one of the main syndrome, appearing after one global accidental irradiation by one ionizing radiation source. The hematopoietic syndrome is characterized by a peripheric blood cell number fall; the cell marrow is reduced too

Recent advances in treatment of severe primary immunodeficiencies [version 1; referees: 2 approved

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Andrew Gennery

2015-12-01

Full Text Available Primary immunodeficiencies are rare, inborn errors that result in impaired, disordered or uncontrolled immune responses. Whilst symptomatic and prophylactic treatment is available, hematopoietic stem cell transplantation is an option for many diseases, leading to cure of the immunodeficiency and establishing normal physical and psychological health. Newborn screening for some diseases, whilst improving outcomes, is focusing research on safer and less toxic treatment strategies, which result in durable and sustainable immune function without adverse effects. New conditioning regimens have reduced the risk of hematopoietic stem cell transplantation, and new methods of manipulating stem cell sources should guarantee a donor for almost all patients. Whilst incremental enhancements in transplantation technique have gradually improved survival outcomes over time, some of these new applications are likely to radically alter our approach to treating primary immunodeficiencies.

Metastatic behaviour of primary human tumours in a zebrafish xenotransplantation model

International Nuclear Information System (INIS)

Marques, Ines J; Bagowski, Christoph P; Weiss, Frank Ulrich; Vlecken, Danielle H; Nitsche, Claudia; Bakkers, Jeroen; Lagendijk, Anne K; Partecke, Lars Ivo; Heidecke, Claus-Dieter; Lerch, Markus M

2009-01-01

Aberrant regulation of cell migration drives progression of many diseases, including cancer cell invasion and metastasis formation. Analysis of tumour invasion and metastasis in living organisms to date is cumbersome and involves difficult and time consuming investigative techniques. For primary human tumours we establish here a simple, fast, sensitive and cost-effective in vivo model to analyse tumour invasion and metastatic behaviour. We fluorescently labelled small explants from gastrointestinal human tumours and investigated their metastatic behaviour after transplantation into zebrafish embryos and larvae. The transparency of the zebrafish embryos allows to follow invasion, migration and micrometastasis formation in real-time. High resolution imaging was achieved through laser scanning confocal microscopy of live zebrafish. In the transparent zebrafish embryos invasion, circulation of tumour cells in blood vessels, migration and micrometastasis formation can be followed in real-time. Xenografts of primary human tumours showed invasiveness and micrometastasis formation within 24 hours after transplantation, which was absent when non-tumour tissue was implanted. Furthermore, primary human tumour cells, when organotopically implanted in the zebrafish liver, demonstrated invasiveness and metastatic behaviour, whereas primary control cells remained in the liver. Pancreatic tumour cells showed no metastatic behaviour when injected into cloche mutant embryos, which lack a functional vasculature. Our results show that the zebrafish is a useful in vivo animal model for rapid analysis of invasion and metastatic behaviour of primary human tumour specimen

Are neural crest stem cells the missing link between hematopoietic and neurogenic niches?

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Cécile eCoste

2015-06-01

Full Text Available Hematopoietic niches are defined as cellular and molecular microenvironments that regulate hematopoietic stem cell (HSC function together with stem cell autonomous mechanisms. Many different cell types have been characterized as contributors to the formation of HSC niches, such as osteoblasts, endothelial cells, Schwann cells, and mesenchymal progenitors. These mesenchymal progenitors have themselves been classified as CXC chemokine ligand (CXCL12-abundant reticular (CAR cells, stem cell factor expressing cells, or nestin-positive mesenchymal stem cells (MSCs, which have been recently identified as neural crest-derived cells (NCSCs. Together, these cells are spatially associated with HSCs and believed to provide appropriate microenvironments for HSC self-renewal, differentiation, mobilization and hibernation both by cell-to-cell contact and soluble factors. Interestingly, it appears that regulatory pathways governing the hematopoietic niche homeostasis are operating in the neurogenic niche as well. Therefore, this review paper aims to compare both the regulation of hematopoietic and neurogenic niches, in order to highlight the role of NCSCs and nervous system components in the development and the regulation of the hematopoietic system.

Are neural crest stem cells the missing link between hematopoietic and neurogenic niches?

Science.gov (United States)

Coste, Cécile; Neirinckx, Virginie; Gothot, André; Wislet, Sabine; Rogister, Bernard

2015-01-01

Hematopoietic niches are defined as cellular and molecular microenvironments that regulate hematopoietic stem cell (HSC) function together with stem cell autonomous mechanisms. Many different cell types have been characterized as contributors to the formation of HSC niches, such as osteoblasts, endothelial cells, Schwann cells, and mesenchymal progenitors. These mesenchymal progenitors have themselves been classified as CXC chemokine ligand (CXCL) 12-abundant reticular (CAR) cells, stem cell factor expressing cells, or nestin-positive mesenchymal stem cells (MSCs), which have been recently identified as neural crest-derived cells (NCSCs). Together, these cells are spatially associated with HSCs and believed to provide appropriate microenvironments for HSC self-renewal, differentiation, mobilization and hibernation both by cell-cell contact and soluble factors. Interestingly, it appears that regulatory pathways governing the hematopoietic niche homeostasis are operating in the neurogenic niche as well. Therefore, this review paper aims to compare both the regulation of hematopoietic and neurogenic niches, in order to highlight the role of NCSCs and nervous system components in the development and the regulation of the hematopoietic system.

Primary structure of the human M2 mitochondrial autoantigen of primary biliary cirrhosis: Dihydrolipoamide acetyltransferase

International Nuclear Information System (INIS)

Coppel, R.L.; McNeilage, L.J.; Surh, C.D.; Van De Water, J.; Spithill, T.W.; Whittingham, S.; Gershwin, M.E.

1988-01-01

Primary biliary cirrhosis is a chronic, destructive autoimmune liver disease of humans. Patient sera are characterized by a high frequency of autoantibodies to a M r 70,000 mitochondrial antigen a component of the M2 antigen complex. The authors have identified a human cDNA clone encoding the complete amino acid sequence of this autoantigen. The predicted structure has significant similarity with the dihydrolipoamide acetyltransferase of the Escherichia coli pyruvate dehydrogenase multienzyme complex. The human sequence preserves the Glu-Thr-Asp-Lys-Ala motif of the lipoyl-binding site and has two potential binding sites. Expressed fragments of the cDNA react strongly with sera from patients with primary biliary cirrhosis but not with sera from patients with autoimmune chronic active hepatitis or sera from healthy subjects

Human Rights Texts: Converting Human Rights Primary Source Documents into Data.

Science.gov (United States)

Fariss, Christopher J; Linder, Fridolin J; Jones, Zachary M; Crabtree, Charles D; Biek, Megan A; Ross, Ana-Sophia M; Kaur, Taranamol; Tsai, Michael

2015-01-01

We introduce and make publicly available a large corpus of digitized primary source human rights documents which are published annually by monitoring agencies that include Amnesty International, Human Rights Watch, the Lawyers Committee for Human Rights, and the United States Department of State. In addition to the digitized text, we also make available and describe document-term matrices, which are datasets that systematically organize the word counts from each unique document by each unique term within the corpus of human rights documents. To contextualize the importance of this corpus, we describe the development of coding procedures in the human rights community and several existing categorical indicators that have been created by human coding of the human rights documents contained in the corpus. We then discuss how the new human rights corpus and the existing human rights datasets can be used with a variety of statistical analyses and machine learning algorithms to help scholars understand how human rights practices and reporting have evolved over time. We close with a discussion of our plans for dataset maintenance, updating, and availability.

Rapid lentiviral transduction preserves the engraftment potential of Fanca(-/-) hematopoietic stem cells.

Science.gov (United States)

Müller, Lars U W; Milsom, Michael D; Kim, Mi-Ok; Schambach, Axel; Schuesler, Todd; Williams, David A

2008-06-01

Fanconi anemia (FA) is a rare recessive syndrome, characterized by congenital anomalies, bone marrow failure, and predisposition to cancer. Two earlier clinical trials utilizing gamma-retroviral vectors for the transduction of autologous FA hematopoietic stem cells (HSCs) required extensive in vitro manipulation and failed to achieve detectable long-term engraftment of transduced HSCs. As a strategy for minimizing ex vivo manipulation, we investigated the use of a "rapid" lentiviral transduction protocol in a murine Fanca(-/-) model. Importantly, while this and most murine models of FA fail to completely mimic the human hematopoietic phenotype, we observed a high incidence of HSC transplant engraftment failure and low donor chimerism after conventional transduction (CT) of Fanca(-/-) donor cells. In contrast, rapid transduction (RT) of Fanca(-/-) HSCs preserved engraftment to the level achieved in wild-type cells, resulting in long-term multilineage engraftment of gene-modified cells. We also demonstrate the correction of the characteristic hypersensitivity of FA cells against the cross-linking agent mitomycin C (MMC), and provide evidence for the advantage of using pharmacoselection as a means of further increasing gene-modified cells after RT. Collectively, these data support the use of rapid lentiviral transduction for gene therapy in FA.

IP3 3-kinase B controls hematopoietic stem cell homeostasis and prevents lethal hematopoietic failure in mice

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Siegemund, Sabine; Rigaud, Stephanie; Conche, Claire; Broaten, Blake; Schaffer, Lana; Westernberg, Luise; Head, Steven Robert

2015-01-01

Tight regulation of hematopoietic stem cell (HSC) homeostasis ensures lifelong hematopoiesis and prevents blood cancers. The mechanisms balancing HSC quiescence with expansion and differentiation into hematopoietic progenitors are incompletely understood. Here, we identify Inositol-trisphosphate 3-kinase B (Itpkb) as an essential regulator of HSC homeostasis. Young Itpkb−/− mice accumulated phenotypic HSC, which were less quiescent and proliferated more than wild-type (WT) controls. Itpkb−/− HSC downregulated quiescence and stemness associated, but upregulated activation, oxidative metabolism, protein synthesis, and lineage associated messenger RNAs. Although they had normal-to-elevated viability and no significant homing defects, Itpkb−/− HSC had a severely reduced competitive long-term repopulating potential. Aging Itpkb−/− mice lost hematopoietic stem and progenitor cells and died with severe anemia. WT HSC normally repopulated Itpkb−/− hosts, indicating an HSC-intrinsic Itpkb requirement. Itpkb−/− HSC showed reduced colony-forming activity and increased stem-cell-factor activation of the phosphoinositide-3-kinase (PI3K) effectors Akt/mammalian/mechanistic target of rapamycin (mTOR). This was reversed by treatment with the Itpkb product and PI3K/Akt antagonist IP4. Transcriptome changes and biochemistry support mTOR hyperactivity in Itpkb−/− HSC. Treatment with the mTOR-inhibitor rapamycin reversed the excessive mTOR signaling and hyperproliferation of Itpkb−/− HSC without rescuing colony forming activity. Thus, we propose that Itpkb ensures HSC quiescence and function through limiting cytokine-induced PI3K/mTOR signaling and other mechanisms. PMID:25788703

Hematopoietic stem and progenitor cells regulate the regeneration of their niche by secreting Angiopoietin-1

Science.gov (United States)

Zhou, Bo O; Ding, Lei; Morrison, Sean J

2015-01-01

Hematopoietic stem cells (HSCs) are maintained by a perivascular niche in bone marrow but it is unclear whether the niche is reciprocally regulated by HSCs. Here, we systematically assessed the expression and function of Angiopoietin-1 (Angpt1) in bone marrow. Angpt1 was not expressed by osteoblasts. Angpt1 was most highly expressed by HSCs, and at lower levels by c-kit+ hematopoietic progenitors, megakaryocytes, and Leptin Receptor+ (LepR+) stromal cells. Global conditional deletion of Angpt1, or deletion from osteoblasts, LepR+ cells, Nes-cre-expressing cells, megakaryocytes, endothelial cells or hematopoietic cells in normal mice did not affect hematopoiesis, HSC maintenance, or HSC quiescence. Deletion of Angpt1 from hematopoietic cells and LepR+ cells had little effect on vasculature or HSC frequency under steady-state conditions but accelerated vascular and hematopoietic recovery after irradiation while increasing vascular leakiness. Hematopoietic stem/progenitor cells and LepR+ stromal cells regulate niche regeneration by secreting Angpt1, reducing vascular leakiness but slowing niche recovery. DOI: http://dx.doi.org/10.7554/eLife.05521.001 PMID:25821987

Interleukin-21 promotes thymopoiesis recovery following hematopoietic stem cell transplantation

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Aurélie Tormo

2017-06-01

Full Text Available Abstract Background Impaired T cell reconstitution remains a major deterrent in the field of bone marrow (BM transplantation (BMT due to pre-conditioning-induced damages inflicted to the thymi of recipient hosts. Given the previously reported thymo-stimulatory property of interleukin (IL-21, we reasoned that its use post-BMT could have a profound effect on de novo T cell development. Methods To evaluate the effect of IL-21 on de novo T cell development in vivo, BM derived from RAG2p-GFP mice was transplanted into LP/J mice. Lymphocyte reconstitution was first assessed using a hematological analyzer and a flow cytometer on collected blood samples. Detailed flow cytometry analysis was then performed on the BM, thymus, and spleen of transplanted animals. Finally, the effect of human IL-21 on thymopoiesis was validated in humanized mice. Results Using a major histocompatibility complex (MHC-matched allogeneic BMT model, we found that IL-21 administration improves immune reconstitution by triggering the proliferation of BM Lin−Sca1+c-kit+ (LSK subsets. The pharmacological effect of IL-21 also culminates in the recovery of both hematopoietic (thymocytes and non-hematopoietic (stromal cells within the thymi of IL-21-treated recipient animals. Although T cells derived from all transplanted groups proliferate, secrete various cytokines, and express granzyme B similarly in response to T cell receptor (TCR stimulation, full regeneration of peripheral naïve CD4+ and CD8+ T cells and normal TCRvβ distribution could only be detected in IL-21-treated recipient mice. Astonishingly, none of the recipient mice who underwent IL-21 treatment developed graft-versus-host disease (GVHD in the MHC-matched allogeneic setting while the graft-versus-tumor (GVT effect was strongly retained. Inhibition of GVHD onset could also be attributed to the enhanced generation of regulatory B cells (B10 observed in the IL-21, but not PBS, recipient mice. We also tested the

Erythroid differentiation of human induced pluripotent stem cells is independent of donor cell type of origin.

Science.gov (United States)

Dorn, Isabel; Klich, Katharina; Arauzo-Bravo, Marcos J; Radstaak, Martina; Santourlidis, Simeon; Ghanjati, Foued; Radke, Teja F; Psathaki, Olympia E; Hargus, Gunnar; Kramer, Jan; Einhaus, Martin; Kim, Jeong Beom; Kögler, Gesine; Wernet, Peter; Schöler, Hans R; Schlenke, Peter; Zaehres, Holm

2015-01-01

Epigenetic memory in induced pluripotent stem cells, which is related to the somatic cell type of origin of the stem cells, might lead to variations in the differentiation capacities of the pluripotent stem cells. In this context, induced pluripotent stem cells from human CD34(+) hematopoietic stem cells might be more suitable for hematopoietic differentiation than the commonly used fibroblast-derived induced pluripotent stem cells. To investigate the influence of an epigenetic memory on the ex vivo expansion of induced pluripotent stem cells into erythroid cells, we compared induced pluripotent stem cells from human neural stem cells and human cord blood-derived CD34(+) hematopoietic stem cells and evaluated their potential for differentiation into hematopoietic progenitor and mature red blood cells. Although genome-wide DNA methylation profiling at all promoter regions demonstrates that the epigenetic memory of induced pluripotent stem cells is influenced by the somatic cell type of origin of the stem cells, we found a similar hematopoietic induction potential and erythroid differentiation pattern of induced pluripotent stem cells of different somatic cell origin. All human induced pluripotent stem cell lines showed terminal maturation into normoblasts and enucleated reticulocytes, producing predominantly fetal hemoglobin. Differences were only observed in the growth rate of erythroid cells, which was slightly higher in the induced pluripotent stem cells derived from CD34(+) hematopoietic stem cells. More detailed methylation analysis of the hematopoietic and erythroid promoters identified similar CpG methylation levels in the induced pluripotent stem cell lines derived from CD34(+) cells and those derived from neural stem cells, which confirms their comparable erythroid differentiation potential. Copyright© Ferrata Storti Foundation.

Inductive potential of recombinant human granulocyte colony-stimulating factor to mature neutrophils from X-irradiated human peripheral blood hematopoietic progenitor cells

International Nuclear Information System (INIS)

Katsumori, Takeo; Yoshino, Hironori; Hayashi, Masako; Takahashi, Kenji; Kashiwakura, Ikuo

2009-01-01

Recombinant human granulocyte colony-stimulating factor (rhG-CSF) has been used for treatment of neutropenia. Filgrastim, Nartograstim, and Lenograstim are clinically available in Japan. However, the differences in potential benefit for radiation-induced disorder between these types of rhG-CSFs remain unknown. Therefore, the effects of three different types of rhG-CSFs on granulocyte progenitor cells and expansion of neutrophils from nonirradiated or 2 Gy X-irradiated human CD34 + hematopoietic progenitor cells were examined. For analysis of granulocyte colony-forming units (CFU-G) and a surviving fraction of CFU-G, nonirradiated or X-irradiated CD34 + cells were cultured in methylcellulose containing rhG-CSF. These cells were cultured in serum-free medium supplemented with rhG-CSF, and the expansion and characteristics of neutrophils were analyzed. All three types of rhG-CSFs increased the number of CFU-G in a dose-dependent manner; however, Lenograstim is superior to others because of CFU-G-derived colony formation at relatively low doses. The surviving fraction of CFU-G was independent of the types of rhG-CSFs. Expansion of neutrophils by rhG-CSF was largely attenuated by X-irradiation, though no significant difference in neutrophil number was observed between the three types of rhG-CSFs under both nonirradiation and X-irradiation conditions. In terms of functional characteristics of neutrophils, Lenograstim-induced neutrophils produced high levels of reactive oxygen species compared to Filgrastim, when rhG-CSF was applied to nonirradiated CD34 + cells. In conclusion, different types of rhG-CSFs lead to different effects when rhG-CSF is applied to nonirradiated CD34 + cells, though Filgrastim, Nartograstim, and Lenograstim show equal effects on X-irradiated CD34 + cells. (author)

The development of human mast cells. An historical reappraisal

Energy Technology Data Exchange (ETDEWEB)

Ribatti, Domenico, E-mail: domenico.ribatti@uniba.it

2016-03-15

The understanding of mast cell (MC) differentiation is derived mainly from in vitro studies of different stages of stem and progenitor cells. The hematopoietic lineage development of human MCs is unique compared to other myeloid-derived cells. Human MCs originate from CD34{sup +}/CD117{sup +}/CD13{sup +}multipotent hematopoietic progenitors, which undergo transendothelial recruitment into peripheral tissues, where they complete differentiation. Stem cell factor (SCF) is a major chemotactic factor for MCs and their progenitors. SCF also elicits cell-cell and cell-substratum adhesion, facilitates the proliferation, and sustains the survival, differentiation, and maturation, of MCs. Because MC maturation is influenced by local microenvironmental factors, different MC phenotypes can develop in different tissues and organs. - Highlights: • Human mast cells originate from CD34/CD117/CD13 positive multipotent hematopoietic progenitors. • Stem cell factor is a major chemotactic factor for mast cells and their progenitors. • Different mast cell phenotypes can develop in different tissues and organs.

The development of human mast cells. An historical reappraisal

International Nuclear Information System (INIS)

Ribatti, Domenico

2016-01-01

The understanding of mast cell (MC) differentiation is derived mainly from in vitro studies of different stages of stem and progenitor cells. The hematopoietic lineage development of human MCs is unique compared to other myeloid-derived cells. Human MCs originate from CD34"+/CD117"+/CD13"+multipotent hematopoietic progenitors, which undergo transendothelial recruitment into peripheral tissues, where they complete differentiation. Stem cell factor (SCF) is a major chemotactic factor for MCs and their progenitors. SCF also elicits cell-cell and cell-substratum adhesion, facilitates the proliferation, and sustains the survival, differentiation, and maturation, of MCs. Because MC maturation is influenced by local microenvironmental factors, different MC phenotypes can develop in different tissues and organs. - Highlights: • Human mast cells originate from CD34/CD117/CD13 positive multipotent hematopoietic progenitors. • Stem cell factor is a major chemotactic factor for mast cells and their progenitors. • Different mast cell phenotypes can develop in different tissues and organs.

[Characterization of epithelial primary culture from human conjunctiva].

Science.gov (United States)

Rivas, L; Blázquez, A; Muñoz-Negrete, F J; López, S; Rebolleda, G; Domínguez, F; Pérez-Esteban, A

2014-01-01

To evaluate primary cultures from human conjunctiva supplemented with fetal bovine serum, autologous serum, and platelet-rich autologous serum, over human amniotic membrane and lens anterior capsules. One-hundred and forty-eight human conjunctiva explants were cultured in CnT50(®) supplemented with 1, 2.5, 5 and 10% fetal bovine serum, autologous serum and platelet-rich autologous serum. Conjunctival samples were incubated at 37°C, 5% CO2 and 95% HR, for 3 weeks. The typical phenotype corresponding to conjunctival epithelial cells was present in all primary cultures. Conjunctival cultures had MUC5AC-positive secretory cells, K19-positive conjunctival cells, and MUC4-positive non-secretory conjunctival cells, but were not corneal phenotype (cytokeratin K3-negative) and fibroblasts (CD90-negative). Conjunctiva epithelial progenitor cells were preserved in all cultures; thus, a cell culture in CnT50(®) supplemented with 1 to 5% autologous serum over human amniotic membrane can provide better information of epithelial cell differentiation for the conjunctival surface reconstruction. Copyright © 2013 Sociedad Española de Oftalmología. Published by Elsevier Espana. All rights reserved.

Regulatory Systems in Bone Marrow for Hematopoietic Stem/Progenitor Cells Mobilization and Homing

Directory of Open Access Journals (Sweden)

P. Alvarez

2013-01-01

Full Text Available Regulation of hematopoietic stem cell release, migration, and homing from the bone marrow (BM and of the mobilization pathway involves a complex interaction among adhesion molecules, cytokines, proteolytic enzymes, stromal cells, and hematopoietic cells. The identification of new mechanisms that regulate the trafficking of hematopoietic stem/progenitor cells (HSPCs cells has important implications, not only for hematopoietic transplantation but also for cell therapies in regenerative medicine for patients with acute myocardial infarction, spinal cord injury, and stroke, among others. This paper reviews the regulation mechanisms underlying the homing and mobilization of BM hematopoietic stem/progenitor cells, investigating the following issues: (a the role of different factors, such as stromal cell derived factor-1 (SDF-1, granulocyte colony-stimulating factor (G-CSF, and vascular cell adhesion molecule-1 (VCAM-1, among other ligands; (b the stem cell count in peripheral blood and BM and influential factors; (c the therapeutic utilization of this phenomenon in lesions in different tissues, examining the agents involved in HSPCs mobilization, such as the different forms of G-CSF, plerixafor, and natalizumab; and (d the effects of this mobilization on BM-derived stem/progenitor cells in clinical trials of patients with different diseases.

Hematopoietic cell transplantation in Fanconi anemia: current evidence, challenges and recommendations.

Science.gov (United States)

Ebens, Christen L; MacMillan, Margaret L; Wagner, John E

2017-01-01

Hematopoietic cell transplantation for Fanconi Anemia (FA) has improved dramatically over the past 40 years. With an enhanced understanding of the intrinsic DNA-repair defect and pathophysiology of hematopoietic failure and leukemogenesis, sequential changes to conditioning and graft engineering have significantly improved the expectation of survival after allogeneic hematopoietic cell transplantation (alloHCT) with incidence of graft failure decreased from 35% to 40% to <10%. Today, five-year overall survival exceeds 90% in younger FA patients with bone marrow failure but remains about 50% in those with hematologic malignancy. Areas covered: We review the evolution of alloHCT contributing to decreased rates of transplant related complications; highlight current challenges including poorer outcomes in cases of clonal hematologic disorders, alloHCT impact on endocrine function and intrinsic FA risk of epithelial malignancies; and describe investigational therapies for prevention and treatment of the hematologic manifestations of FA. Expert commentary: Current methods allow for excellent survival following alloHCT for FA associated BMF irrespective of donor hematopoietic cell source. Alternative curative approaches, such as gene therapy, are being explored to eliminate the risks of GVHD and minimize therapy-related adverse effects.

Allogeneic hematopoietic stem cell transplantation in Primary Cutaneous T Cell Lymphoma.

Science.gov (United States)

Cudillo, Laura; Cerretti, Raffaella; Picardi, Alessandra; Mariotti, Benedetta; De Angelis, Gottardo; Cantonetti, Maria; Postorino, Massimiliano; Ceresoli, Eleonora; De Santis, Giovanna; Nasso, Daniela; Pisani, Francesco; Scala, Enrico; Di Piazza, Fabio; Lanti, Alessandro

2018-06-01

In our retrospective study, 16 patients affected by advanced cutaneous T cell lymphoma (CTCL) underwent allogeneic hematopoietic stem cell transplantation (HSCT). Two patients (12.5%) were in complete remission (CR), nine (56.3%) in partial remission (PR), and five (31.2%) with active disease. The patients were transplanted from an HLA-identical (n = 7) from a mismatched (n = 1) or haploidentical (n = 1) sibling, from matched unrelated donor (n = 5), or from a single cord blood unit (n = 2). Conditioning regimen was standard myeloablative in 6 patients and at reduced intensity in 10. Seven patients died from non relapse mortality (NRM) and four patients relapsed or progressed, three of them achieved a second CR after donor lymphocyte infusion (DLI) or chemotherapy plus DLI. To date, with a median follow-up of 76 months (range 6-130), nine patients are alive, eight in CR, and one with active disease. Overall survival (OS) and disease-free survival (DFS) at 1 and 10 years are 61% (95% CI 40-91%) and 54% (95% CI 33-86%), 40% (95% CI 22-74%), and 34% (95% CI 16-68%), respectively. The time from diagnosis to transplant seems to influence negatively both OS (log-rank p < 0.04) and DFS (log-rank p < 0.05). Our results confirm on a long follow-up that CTCL appears particularly susceptible to the graft versus lymphoma (GVL) effect, so that allogeneic HSCT represents a possibility of cure for advanced CTCL. The timing of HSCT in the clinical course of disease remains an open issue.

Studies on hematopoietic cell apoptosis and the relative gene expression in irradiated mouse bone marrow

International Nuclear Information System (INIS)

Peng Ruiyun; Wang Dewen; Xiong Chengqi; Gao Yabing; Yang Hong; Cui Yufang; Wang Baozhen

2001-01-01

Objective: To study apoptosis and expressions bcl-2 and p53 in irradiated mouse bone marrow. Methods: LACA mice were irradiated with 60 Co γ-rays. By means of in situ terminal labelling, in situ hybridization and image analysis, the authors studied radiation-induced apoptosis of hematopoietic cells and the expressions of bcl-2 and p53. Results: The characteristics of apoptosis appeared in hematopoietic cells at 6 hrs after irradiation. The expression of bcl-2 was obviously decreased when apoptosis of hematopoietic cells occurred, whereas it increased in the early recovery phase; p53 protein increased during both apoptosis of hematopoietic cells and the recovery phase, and mutant type p53 DNA was positive only in the recovery phase. Conclusion: Radiation may induced apoptosis of hematopoietic cells in a dose-dependent manner; Both bcl-2 and p53 genes play an important role in apoptosis and recovery phase

Selection of genetically modified hematopoietic cells in vitro and in vivo using alkylating agent lysomustine.

Science.gov (United States)

Rozov, F N; Grinenko, T S; Levit, G L; Krasnov, V P; Belyavsky, A V

2010-09-15

Efficient gene transfer into hematopoietic stem cells is vital for the success of gene therapy of hematopoietic and immune system disorders. An in vivo selection system based on a mutant form of the O(6)-methylguanine-DNA-methyltransferase gene (MGMTm) is considered one of the more promising strategies for expansion of hematopoietic cells transduced with viral vectors. Here we demonstrate that MGMTm-expressing cells can be efficiently selected using lysomustine, a nitrosourea derivative of lysine. K562 and murine bone marrow cells expressing MGMTm are protected from the cytotoxic action of lysomustine in vitro. We also show in a murine model that MGMTm-transduced hematopoietic cells can be expanded in vivo on transplantation into sublethally irradiated recipients followed by lysomustine treatment. These results indicate that lysomustine can be used as a potent novel chemoselection drug applicable for gene therapy of hematopoietic and immune system disorders. 2010 Elsevier Inc. All rights reserved.

Secreted protein Del-1 regulates myelopoiesis in the hematopoietic stem cell niche.

Science.gov (United States)

Mitroulis, Ioannis; Chen, Lan-Sun; Singh, Rashim Pal; Kourtzelis, Ioannis; Economopoulou, Matina; Kajikawa, Tetsuhiro; Troullinaki, Maria; Ziogas, Athanasios; Ruppova, Klara; Hosur, Kavita; Maekawa, Tomoki; Wang, Baomei; Subramanian, Pallavi; Tonn, Torsten; Verginis, Panayotis; von Bonin, Malte; Wobus, Manja; Bornhäuser, Martin; Grinenko, Tatyana; Di Scala, Marianna; Hidalgo, Andres; Wielockx, Ben; Hajishengallis, George; Chavakis, Triantafyllos

2017-10-02

Hematopoietic stem cells (HSCs) remain mostly quiescent under steady-state conditions but switch to a proliferative state following hematopoietic stress, e.g., bone marrow (BM) injury, transplantation, or systemic infection and inflammation. The homeostatic balance between quiescence, self-renewal, and differentiation of HSCs is strongly dependent on their interactions with cells that constitute a specialized microanatomical environment in the BM known as the HSC niche. Here, we identified the secreted extracellular matrix protein Del-1 as a component and regulator of the HSC niche. Specifically, we found that Del-1 was expressed by several cellular components of the HSC niche, including arteriolar endothelial cells, CXCL12-abundant reticular (CAR) cells, and cells of the osteoblastic lineage. Del-1 promoted critical functions of the HSC niche, as it regulated long-term HSC (LT-HSC) proliferation and differentiation toward the myeloid lineage. Del-1 deficiency in mice resulted in reduced LT-HSC proliferation and infringed preferentially upon myelopoiesis under both steady-state and stressful conditions, such as hematopoietic cell transplantation and G-CSF- or inflammation-induced stress myelopoiesis. Del-1-induced HSC proliferation and myeloid lineage commitment were mediated by β3 integrin on hematopoietic progenitors. This hitherto unknown Del-1 function in the HSC niche represents a juxtacrine homeostatic adaptation of the hematopoietic system in stress myelopoiesis.

Proton MR spectroscopy of hyperplastic hematopoietic marrow in aplastic anemia

Energy Technology Data Exchange (ETDEWEB)

Amano, Yasuo; Kumazaki, Tatsuo [Nippon Medical School, Tokyo (Japan); Arai, Nobuyuki

1997-04-01

The purpose of this study was to compare the findings of magnetic resonance (MR) spectroscopy of hyperplastic hematopoietic marrow with those of normal bone marrow. Twenty-four samples of normal marrow from eight control subjects and 19 samples of hyperplastic marrow in aplastic anemia were examined with a 1.5 T MR unit. The former showed low intensity on opposed-phase T1-weighted images, while the latter showed high intensity on both fast STIR and opposed-phase T1-weighted images. MR spectroscopy quantitatively confirmed that the water; fat ratio was increased and the transverse relaxation time of water was changed in hyperplastic bone marrow, compared with normal bone marrow. In summary, MR imaging is able to detect hematopoietic regions among a wide range of bone marrow of aplastic anemia, while MR spectroscopy allowed us to quantitatively analyze the cell population of hyperplastic hematopoietic marrow in aplastic anemia. (author)

Proton MR spectroscopy of hyperplastic hematopoietic marrow in aplastic anemia

International Nuclear Information System (INIS)

Amano, Yasuo; Kumazaki, Tatsuo; Arai, Nobuyuki.

1997-01-01

The purpose of this study was to compare the findings of magnetic resonance (MR) spectroscopy of hyperplastic hematopoietic marrow with those of normal bone marrow. Twenty-four samples of normal marrow from eight control subjects and 19 samples of hyperplastic marrow in aplastic anemia were examined with a 1.5 T MR unit. The former showed low intensity on opposed-phase T1-weighted images, while the latter showed high intensity on both fast STIR and opposed-phase T1-weighted images. MR spectroscopy quantitatively confirmed that the water; fat ratio was increased and the transverse relaxation time of water was changed in hyperplastic bone marrow, compared with normal bone marrow. In summary, MR imaging is able to detect hematopoietic regions among a wide range of bone marrow of aplastic anemia, while MR spectroscopy allowed us to quantitatively analyze the cell population of hyperplastic hematopoietic marrow in aplastic anemia. (author)

28Si total body irradiation injures bone marrow hematopoietic stem cells via induction of cellular apoptosis

Science.gov (United States)

Chang, Jianhui; Feng, Wei; Wang, Yingying; Allen, Antiño R.; Turner, Jennifer; Stewart, Blair; Raber, Jacob; Hauer-Jensen, Martin; Zhou, Daohong; Shao, Lijian

2017-05-01

Long-term space mission exposes astronauts to a radiation environment with potential health hazards. High-energy charged particles (HZE), including 28Si nuclei in space, have deleterious effects on cells due to their characteristics with high linear energy transfer and dense ionization. The influence of 28Si ions contributes more than 10% to the radiation dose equivalent in the space environment. Understanding the biological effects of 28Si irradiation is important to assess the potential health hazards of long-term space missions. The hematopoietic system is highly sensitive to radiation injury and bone marrow (BM) suppression is the primary life-threatening injuries after exposure to a moderate dose of radiation. Therefore, in the present study we investigated the acute effects of low doses of 28Si irradiation on the hematopoietic system in a mouse model. Specifically, 6-month-old C57BL/6 J mice were exposed to 0.3, 0.6 and 0.9 Gy 28Si (600 MeV) total body irradiation (TBI). The effects of 28Si TBI on BM hematopoietic stem cells (HSCs) and hematopoietic progenitor cells (HPCs) were examined four weeks after the exposure. The results showed that exposure to 28Si TBI dramatically reduced the frequencies and numbers of HSCs in irradiated mice, compared to non-irradiated controls, in a radiation dose-dependent manner. In contrast, no significant changes were observed in BM HPCs regardless of radiation doses. Furthermore, irradiated HSCs exhibited a significant impairment in clonogenic ability. These acute effects of 28Si irradiation on HSCs may be attributable to radiation-induced apoptosis of HSCs, because HSCs, but not HPCs, from irradiated mice exhibited a significant increase in apoptosis in a radiation dose-dependent manner. However, exposure to low doses of 28Si did not result in an increased production of reactive oxygen species and DNA damage in HSCs and HPCs. These findings indicate that exposure to 28Si irradiation leads to acute HSC damage.

Hematopoietic stem cell origin of connective tissues.

Science.gov (United States)

Ogawa, Makio; Larue, Amanda C; Watson, Patricia M; Watson, Dennis K

2010-07-01

Connective tissue consists of "connective tissue proper," which is further divided into loose and dense (fibrous) connective tissues and "specialized connective tissues." Specialized connective tissues consist of blood, adipose tissue, cartilage, and bone. In both loose and dense connective tissues, the principal cellular element is fibroblasts. It has been generally believed that all cellular elements of connective tissue, including fibroblasts, adipocytes, chondrocytes, and bone cells, are generated solely by mesenchymal stem cells. Recently, a number of studies, including those from our laboratory based on transplantation of single hematopoietic stem cells, strongly suggested a hematopoietic stem cell origin of these adult mesenchymal tissues. This review summarizes the experimental evidence for this new paradigm and discusses its translational implications. Copyright 2010 ISEH - Society for Hematology and Stem Cells. All rights reserved.

Proteomic cornerstones of hematopoietic stem cell differentiation

DEFF Research Database (Denmark)

Klimmeck, Daniel; Hansson, Jenny; Raffel, Simon

2012-01-01

Regenerative tissues such as the skin epidermis, the intestinal mucosa or the hematopoietic system are organized in a hierarchical manner with stem cells building the top of this hierarchy. Somatic stem cells harbor the highest self-renewal activity and generate a series of multipotent progenitors...... which differentiate into lineage committed progenitors and subsequently mature cells. In this report, we applied an in-depth quantitative proteomic approach to analyze and compare the full proteomes of ex vivo isolated and FACS-sorted populations highly enriched for either multipotent hematopoietic stem....../progenitor cells (HSPCs, Lin(neg)Sca-1(+)c-Kit(+)) or myeloid committed precursors (Lin(neg)Sca-1(-)c-Kit(+)). By employing stable isotope dimethyl labeling and high-resolution mass spectrometry, more than 5,000 proteins were quantified. From biological triplicate experiments subjected to rigorous statistical...

Analysis and manipulation of hematopoietic progenitor and stem cells from murine embryonic tissues

NARCIS (Netherlands)

A. Medvinsky (Alexander); S. Taoudi (Samir); S.C. Mendes (Sandra); E.A. Dzierzak (Elaine)

2008-01-01

textabstractHematopoietic development begins in several locations in the mammalian embryo: yolk sac, aorta-gonad-mesonephros region (AGM), and the chorio-allantoic placenta. Generation of the most potent cells, adult definitive hematopoietic stem cells (HSCs), occurs within the body of the mouse

OP9-Lhx2 stromal cells facilitate derivation of hematopoietic progenitors both in vitro and in vivo

Directory of Open Access Journals (Sweden)

Xiaoli Chen

2015-09-01

Full Text Available Generating engraftable hematopoietic stem cells (HSCs from pluripotent stem cells (PSCs is an ideal approach for obtaining induced HSCs for cell therapy. However, the path from PSCs to robustly induced HSCs (iHSCs in vitro remains elusive. We hypothesize that the modification of hematopoietic niche cells by transcription factors facilitates the derivation of induced HSCs from PSCs. The Lhx2 transcription factor is expressed in fetal liver stromal cells but not in fetal blood cells. Knocking out Lhx2 leads to a fetal hematopoietic defect in a cell non-autonomous role. In this study, we demonstrate that the ectopic expression of Lhx2 in OP9 cells (OP9-Lhx2 accelerates the hematopoietic differentiation of PSCs. OP9-Lhx2 significantly increased the yields of hematopoietic progenitor cells via co-culture with PSCs in vitro. Interestingly, the co-injection of OP9-Lhx2 and PSCs into immune deficient mice also increased the proportion of hematopoietic progenitors via the formation of teratomas. The transplantation of phenotypic HSCs from OP9-Lhx2 teratomas but not from the OP9 control supported a transient repopulating capability. The upregulation of Apln gene by Lhx2 is correlated to the hematopoietic commitment property of OP9-Lhx2. Furthermore, the enforced expression of Apln in OP9 cells significantly increased the hematopoietic differentiation of PSCs. These results indicate that OP9-Lhx2 is a good cell line for regeneration of hematopoietic progenitors both in vitro and in vivo.

Impact of cyclophosphamide dose of conditioning on the outcome of allogeneic hematopoietic stem cell transplantation for aplastic anemia from human leukocyte antigen-identical sibling.

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Mori, Takehiko; Koh, Hideo; Onishi, Yasushi; Kako, Shinichi; Onizuka, Makoto; Kanamori, Heiwa; Ozawa, Yukiyasu; Kato, Chiaki; Iida, Hiroatsu; Suzuki, Ritsuro; Ichinohe, Tatsuo; Kanda, Yoshinobu; Maeda, Tetsuo; Nakao, Shinji; Yamazaki, Hirohito

2016-04-01

The standard conditioning regimen in allogeneic hematopoietic stem cell transplantation (HSCT) for aplastic anemia from a human leukocyte antigen (HLA)-identical sibling has been high-dose cyclophosphamide (CY 200 mg/kg). In the present study, results for 203 patients with aplastic anemia aged 16 years or older who underwent allogeneic HSCT from HLA-identical siblings were retrospectively analyzed using the registry database of Japan Society for Hematopoietic Cell Transplantation. Conditioning regimens were defined as a (1) high-dose CY (200 mg/kg or greater)-based (n = 117); (2) reduced-dose CY (100 mg/kg or greater, but less than 200 mg/kg)-based (n = 38); and (3) low-dose CY (less than 100 mg/kg)-based (n = 48) regimen. Patient age and the proportion of patients receiving fludarabine were significantly higher in the reduced- and low-dose CY groups than the high-dose CY group. Engraftment was comparable among the groups. Five-year overall survival (OS) tended to be higher in the low-dose CY group [93.0 % (95 % CI 85.1-100.0 %)] than the high-dose CY [84.2 % (95 % CI 77.1-91.3 %)] or reduced-dose CY groups [83.8 % (95 % CI 71.8-95.8 %); P = 0.214]. Age-adjusted OS was higher in the low-dose CY group than the high- and reduced-dose CY groups with borderline significance (P = 0.067). These results suggest that CY dose can safely be reduced without increasing graft rejection by adding fludarabine in allogeneic HSCT for aplastic anemia from an HLA-identical sibling.

The hematopoietic transcription factor PU.1 regulates RANK gene expression in myeloid progenitors

International Nuclear Information System (INIS)

Kwon, Oh Hyung; Lee, Chong-Kil; Lee, Young Ik; Paik, Sang-Gi; Lee, Hyun-Jun

2005-01-01

Osteoclasts are bone resorbing cells of hematopoietic origin. The hematopoietic transcription factor PU.1 is critical for osteoclastogenesis; however, the molecular mechanisms of PU.1-regulated osteoclastogenesis have not been explored. Here, we present evidence that the receptor activator of nuclear factor κB (RANK) gene that has been shown to be crucial for osteoclastogenesis is a transcriptional target of PU.1. The PU.1 -/- progenitor cells failed to express the RANK gene and reconstitution of PU.1 in these cells induced RANK expression. Treatment of the PU.1 reconstituted cells with M-CSF and RANKL further augmented the RANK gene expression. To explore the regulatory mechanism of the RANK gene expression by PU.1, we have cloned the human RANK promoter. Transient transfection assays have revealed that the 2.2-kb RANK promoter was functional in a monocyte line RAW264.7, whereas co-transfection of PU.1 transactivated the RANK promoter in HeLa cells. Taken together, these results suggest that PU.1 regulates the RANK gene transcription and this may represent one of the key roles of PU.1 in osteoclast differentiation

An abnormal bone marrow microenvironment contributes to hematopoietic dysfunction in Fanconi anemia.

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Zhou, Yuan; He, Yongzheng; Xing, Wen; Zhang, Peng; Shi, Hui; Chen, Shi; Shi, Jun; Bai, Jie; Rhodes, Steven D; Zhang, Fengqui; Yuan, Jin; Yang, Xianlin; Zhu, Xiaofan; Li, Yan; Hanenberg, Helmut; Xu, Mingjiang; Robertson, Kent A; Yuan, Weiping; Nalepa, Grzegorz; Cheng, Tao; Clapp, D Wade; Yang, Feng-Chun

2017-06-01

Fanconi anemia is a complex heterogeneous genetic disorder with a high incidence of bone marrow failure, clonal evolution to acute myeloid leukemia and mesenchymal-derived congenital anomalies. Increasing evidence in Fanconi anemia and other genetic disorders points towards an interdependence of skeletal and hematopoietic development, yet the impact of the marrow microenvironment in the pathogenesis of the bone marrow failure in Fanconi anemia remains unclear. Here we demonstrated that mice with double knockout of both Fancc and Fancg genes had decreased bone formation at least partially due to impaired osteoblast differentiation from mesenchymal stem/progenitor cells. Mesenchymal stem/progenitor cells from the double knockout mice showed impaired hematopoietic supportive activity. Mesenchymal stem/progenitor cells of patients with Fanconi anemia exhibited similar cellular deficits, including increased senescence, reduced proliferation, impaired osteoblast differentiation and defective hematopoietic stem/progenitor cell supportive activity. Collectively, these studies provide unique insights into the physiological significance of mesenchymal stem/progenitor cells in supporting the marrow microenvironment, which is potentially of broad relevance in hematopoietic stem cell transplantation. Copyright© Ferrata Storti Foundation.

Flotillins are involved in the polarization of primitive and mature hematopoietic cells.

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Lawrence Rajendran

Full Text Available BACKGROUND: Migration of mature and immature leukocytes in response to chemokines is not only essential during inflammation and host defense, but also during development of the hematopoietic system. Many molecules implicated in migratory polarity show uniform cellular distribution under non-activated conditions, but acquire a polarized localization upon exposure to migratory cues. METHODOLOGY/PRINCIPAL FINDINGS: Here, we present evidence that raft-associated endocytic proteins (flotillins are pre-assembled in lymphoid, myeloid and primitive hematopoietic cells and accumulate in the uropod during migration. Furthermore, flotillins display a polarized distribution during immunological synapse formation. Employing the membrane lipid-order sensitive probe Laurdan, we show that flotillin accumulation in the immunological synapse is concomittant with membrane ordering in these regions. CONCLUSIONS: Together with the observation that flotillin polarization does not occur in other polarized cell types such as polarized epithelial cells, our results suggest a specific role for flotillins in hematopoietic cell polarization. Based on our results, we propose that in hematopoietic cells, flotillins provide intrinsic cues that govern segregation of certain microdomain-associated molecules during immune cell polarization.

Explanation of application standards of hematopoietic stimulating factors in the treatment of acute radiation sickness

International Nuclear Information System (INIS)

Xing Zhiwei; Jiang Enhai; Wang Guilin; Luo Qingliang

2012-01-01

Occupational standard of the Ministry of health-Application Standards of Hematopoietic Stimulating Factors in the Treatment of Acute Radiation Sickness has been completed as a draft standard. Based on the wide study and analysis of related animal experimental literature about hematopoietic stimulating factor in the treatment of acute radiation sickness and domestic and foreign clinical reports about application of hematopoietic stimulating factor in radiation accidents in the past decade, the standard was enacted according to the suggestions of International Atomic Energy Agency and the United States Strategic National Stockpile Radiation Working Group and European countries about the application of hematopoietic stimulating factor. It is mainly used for nuclear accident emergency and the treatment of the bone marrow form of acute radiation sickness caused by radiation accidents. It also applies to other hematopoietic failure diseases. In order to implement this standard correctly, the relevant contents of the standard were interpreted in this article. (authors)

The slippery slope of hematopoietic stem cell aging.

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Wahlestedt, Martin; Bryder, David

2017-12-01

The late stages of life, in most species including humans, are associated with a decline in the overall maintenance and health of the organism. This applies also to the hematopoietic system, where aging is not only associated with an increased predisposition for hematological malignancies, but also identified as a strong comorbidity factor for other diseases. Research during the last two decades has proposed that alterations at the level of hematopoietic stem cells (HSCs) might be a root cause for the hematological changes observed with age. However, the recent realization that not all HSCs are alike with regard to fundamental stem cell properties such as self-renewal and lineage potential has several implications for HSC aging, including the synchrony and the stability of the aging HSC state. To approach HSC aging from a clonal perspective, we recently took advantage of technical developments in cellular barcoding and combined this with the derivation of induced pluripotent stem cells (iPSCs). This allowed us to selectively approach HSCs functionally affected by age. The finding that such iPSCs were capable of fully regenerating multilineage hematopoiesis upon morula/blastocyst complementation provides compelling evidence that many aspects of HSC aging can be reversed, which indicates that a central mechanism underlying HSC aging is a failure to uphold the epigenomes associated with younger age. Here we discuss these findings in the context of the underlying causes that might influence HSC aging and the requirements and prospects for restoration of the aging HSC epigenome. Copyright © 2017 ISEH – Society for Hematology and Stem Cells. Published by Elsevier Inc. All rights reserved.

The many faces of hematopoietic stem cell heterogeneity

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2016-01-01

Not all hematopoietic stem cells (HSCs) are alike. They differ in their physical characteristics such as cell cycle status and cell surface marker phenotype, they respond to different extrinsic signals, and they have different lineage outputs following transplantation. The growing body of evidence that supports heterogeneity within HSCs, which constitute the most robust cell fraction at the foundation of the adult hematopoietic system, is currently of great interest and raises questions as to why HSC subtypes exist, how they are generated and whether HSC heterogeneity affects leukemogenesis or treatment options. This Review provides a developmental overview of HSC subtypes during embryonic, fetal and adult stages of hematopoiesis and discusses the possible origins and consequences of HSC heterogeneity. PMID:27965438

Establishing an autologous versus allogeneic hematopoietic cell transplant program in nations with emerging economies.

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Chaudhri, Naeem A; Aljurf, Mahmoud; Almohareb, Fahad I; Alzahrani, Hazzaa A; Bashir, Qaiser; Savani, Bipin; Gupta, Vikas; Hashmi, Shahrukh K

2017-12-01

More than 70,000 hematopoietic cell transplants are currently performed each year, and these continue to increase every year. However, there is a significant variation in the number of absolute transplants and transplant rates between centers, countries, and global regions. The prospect for emerging countries to develop a hematopoietic cell transplantation (HCT) program, as well as to decide on whether autologous HCT (auto-HCT) or allogeneic HCT (allo-HCT) should be established to start with, relies heavily on factors that can explain differences between these two procedures. Major factors that will influence a decision about establishing the type of HCT program are macroeconomic factors such as organization of the healthcare network, available resources and infrastructure. Prevalence of specific diseases in the region as well genetic background of donors and recipients will also influence the mandate or priority of the HCT in the national healthcare plan to explain some of the country-specific differences. Furthermore, microeconomic factors play a role, such as center-specific experience in treating various disorders requiring hematopoietic stem cell transplantation, along with accreditation status and patient volume. The objective of the transplant procedure was to improve the survival and quality of life of patients. The regional difference that one notices in emerging countries about the higher number of allo-HCT compared with auto-HCT procedures performed is primarily based on suboptimal healthcare network in treating various malignant disorders that are the primary indication for auto-stem cell transplantation. In this context, nonmalignant disorders such as bone marrow failure syndromes, inherited genetic disorders and hemoglobinopathies have become the major indication for stem cell transplantation. Better understanding of these factors will assist in establishing new transplant centers in the emerging countries to achieve their specific objectives and

Elevated Mcl-1 perturbs lymphopoiesis, promotes transformation of hematopoietic stem/progenitor cells, and enhances drug resistance

OpenAIRE

Campbell, Kirsteen J.; Bath, Mary L.; Turner, Marian L.; Vandenberg, Cassandra J.; Bouillet, Philippe; Metcalf, Donald; Scott, Clare L.; Cory, Suzanne

2010-01-01

Diverse human cancers with poor prognosis, including many lymphoid and myeloid malignancies, exhibit high levels of Mcl-1. To explore the impact of Mcl-1 overexpression on the hematopoietic compartment, we have generated vavP-Mcl-1 transgenic mice. Their lymphoid and myeloid cells displayed increased resistance to a variety of cytotoxic agents. Myelopoiesis was relatively normal, but lymphopoiesis was clearly perturbed, with excess mature B and T cells accumulating. Rather than the follicular...

The Genetic Landscape of Hematopoietic Stem Cell Frequency in Mice

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Xiaoying Zhou

2015-07-01

Full Text Available Prior efforts to identify regulators of hematopoietic stem cell physiology have relied mainly on candidate gene approaches with genetically modified mice. Here we used a genome-wide association study (GWAS strategy with the hybrid mouse diversity panel to identify the genetic determinants of hematopoietic stem/progenitor cell (HSPC frequency. Among 108 strains, we observed ∼120- to 300-fold variation in three HSPC populations. A GWAS analysis identified several loci that were significantly associated with HSPC frequency, including a locus on chromosome 5 harboring the homeodomain-only protein gene (Hopx. Hopx previously had been implicated in cardiac development but was not known to influence HSPC biology. Analysis of the HSPC pool in Hopx−/− mice demonstrated significantly reduced cell frequencies and impaired engraftment in competitive repopulation assays, thus providing functional validation of this positional candidate gene. These results demonstrate the power of GWAS in mice to identify genetic determinants of the hematopoietic system.

Allogeneic Hematopoietic Stem Cell Transplantation in the Treatment of Human C1q Deficiency: The Karolinska Experience.

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Olsson, Richard F; Hagelberg, Stefan; Schiller, Bodil; Ringdén, Olle; Truedsson, Lennart; Åhlin, Anders

2016-06-01

Human C1q deficiency is associated with systemic lupus erythematosus (SLE) and increased susceptibility to severe bacterial infections. These patients require extensive medical therapy and some develop treatment-resistant disease. Because C1q is produced by monocytes, it has been speculated that allogeneic hematopoietic stem cell transplantation (allo-HSCT) may cure this disorder. We have so far treated 5 patients with C1q deficiency. In 3 cases, SLE symptoms remained relatively mild after the start of medical therapy, but 2 patients developed treatment-resistant SLE, and we decided to pursue treatment with allo-HSCT. For this purpose, we chose a conditioning regimen composed of treosulfan (14 g/m) and fludarabine (30 mg/m) started on day -6 and given for 3 and 5 consecutive days, respectively. Thymoglobulin was given at a cumulative dose of 8 mg/kg, and graft-versus-host disease prophylaxis was composed of cyclosporine and methotrexate. A 9-year-old boy and a 12-year-old girl with refractory SLE restored C1q production after allo-HSCT. This resulted in normal functional properties of the classical complement pathway followed by reduced severity of SLE symptoms. The boy developed posttransplant lymphoproliferative disease, which resolved after treatment with rituximab and donor lymphocyte infusion. Unfortunately, donor lymphocyte infusion induced severe cortisone-resistant gastrointestinal graft-versus-host disease, and the patient died from multiple organ failure 4 months after transplantation. The girl is doing well 33 months after transplantation, and clinically, all signs of SLE have resolved. Allo-HSCT can cure SLE in human C1q deficiency and should be considered early in subjects resistant to medical therapy.

Differentiation potential of human CD133 positive hematopoietic stem cells into motor neuron- like cells, in vitro.

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Moghaddam, Sepideh Alavi; Yousefi, Behnam; Sanooghi, Davood; Faghihi, Faezeh; Hayati Roodbari, Nasim; Bana, Nikoo; Joghataei, Mohammad Taghi; Pooyan, Paria; Arjmand, Babak

2017-12-01

Spinal cord injuries and motor neuron-related disorders impact on life of many patients around the world. Since pharmacotherapy and surgical approaches were not efficient to regenerate these types of defects; stem cell therapy as a good strategy to restore the lost cells has become the focus of interest among the scientists. Umbilical cord blood CD133 + hematopoietic stem cells (UCB- CD133 + HSCs) with self- renewal property and neural lineage differentiation capacity are ethically approved cell candidate for use in regenerative medicine. In this regard the aim of this study was to quantitatively evaluate the capability of these cells to differentiate into motor neuron-like cells (MNL), in vitro. CD133 + HSCs were isolated from human UCB using MACS system. After cell characterization using flow cytometry, the cells were treated with a combination of Retinoic acid, Sonic hedgehog, Brain derived neurotrophic factor, and B27 through a 2- step procedure for two weeks. The expression of MN-specific markers was examined using qRT- PCR, flow cytometry and immunocytochemistry. By the end of the two-week differentiation protocol, CD133 + cells acquired unipolar MNL morphology with thin and long neurites. The expression of Isl-1(62.15%), AChE (41.83%), SMI-32 (21.55%) and Nestin (17.46%) was detected using flow cytometry and immunocytochemistry. The analysis of the expression of PAX6, ISL-1, ACHE, CHAT and SMI-32 revealed that MNLs present these neural markers at levels comparable with undifferentiated cells. In Conclusion Human UCB- CD133 + HSCs are remarkably potent cell candidates to transdifferentiate into motor neuron-like cells, in vitro. Copyright © 2017. Published by Elsevier B.V.

Inactivation of the forkhead transcription factor FoxO3 is essential for PKB-mediated survival of hematopoietic progenitor cells by kit ligand

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Engström, Maria; Karlsson, Richard; Jönsson, Jan-Ingvar

2003-01-01

OBJECTIVE: Kit ligand (KL) is a major survival factor for hematopoietic stem cells. Although anti-apoptotic bcl-2 family members are expressed in these cells, the survival effects by KL appear to involve other mechanisms. Survival signals can also be elicited by the activation of phosphatidylinos......OBJECTIVE: Kit ligand (KL) is a major survival factor for hematopoietic stem cells. Although anti-apoptotic bcl-2 family members are expressed in these cells, the survival effects by KL appear to involve other mechanisms. Survival signals can also be elicited by the activation......, immunofluorescence, and subcellular fractionation, we analyzed the effects of KL on PKB and different forkhead family members in two factor-dependent cell lines, FDCP-mix and FDC-P1, as well as primary mouse bone marrow-derived Lin(-) progenitors. Forced overexpression of triple mutated form of FoxO3 by retroviral...

Human primary visual cortex topography imaged via positron tomography

International Nuclear Information System (INIS)

Schwartz, E.L.; Christman, D.R.; Wolf, A.P.

1984-01-01

The visuotopic structure of primary visual cortex was studied in a group of 7 human volunteers using positron emission transaxial tomography (PETT) and 18 F-labeled 2-deoxy-2-fluoro-D-glucose ([ 18 F]DG). A computer animation was constructed with a spatial structure which was matched to estimates of human cortical magnification factor and to striate cortex stimulus preferences. A lateralized cortical 'checker-board' pattern of [ 18 F]DG was stimulated in primary visual cortex by having subjects view this computer animation following i.v. injection of [ 18 F]DG. The spatial structure of the stimulus was designed to produce an easily recognizable 'signature' in a series of 9 serial PETT scans obtained from each of a group of 7 volunteers. The predicted lateralized topographic 'signature' was observed in 6 of 7 subjects. Applications of this method for further PETT studies of human visual cortex are discussed. (Auth.)

Latexin Inactivation Enhances Survival and Long-Term Engraftment of Hematopoietic Stem Cells and Expands the Entire Hematopoietic System in Mice

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Yi Liu

2017-04-01

Full Text Available Summary: Natural genetic diversity offers an important yet largely untapped resource to decipher the molecular mechanisms regulating hematopoietic stem cell (HSC function. Latexin (Lxn is a negative stem cell regulatory gene identified on the basis of genetic diversity. By using an Lxn knockout mouse model, we found that Lxn inactivation in vivo led to the physiological expansion of the entire hematopoietic hierarchy. Loss of Lxn enhanced the competitive repopulation capacity and survival of HSCs in a cell-intrinsic manner. Gene profiling of Lxn-null HSCs showed altered expression of genes enriched in cell-matrix and cell-cell interactions. Thrombospondin 1 (Thbs1 was a potential downstream target with a dramatic downregulation in Lxn-null HSCs. Enforced expression of Thbs1 restored the Lxn inactivation-mediated HSC phenotypes. This study reveals that Lxn plays an important role in the maintenance of homeostatic hematopoiesis, and it may lead to development of safe and effective approaches to manipulate HSCs for clinical benefit. : In this article, Liang and colleagues show that loss of latexin in vivo expands the HSC population and increases their survival and engraftment. Latexin regulates HSC function and hematopoiesis via the Thbs1 signaling pathway. Keywords: latexin, hematopoietic stem cell, repopulating advantage, expansion, survival, thrombospondin 1

Recent advances in hematopoietic stem cell biology

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Bonde, Jesper; Hess, David A; Nolta, Jan A

2004-01-01

PURPOSE OF REVIEW: Exciting advances have been made in the field of hematopoietic stem cell biology during the past year. This review summarizes recent progress in the identification, culture, and in vivo tracking of hematopoietic stem cells. RECENT FINDINGS: The roles of Wnt and Notch proteins...... in regulating stem cell renewal in the microenvironment, and how these molecules can be exploited in ex vivo stem cell culture, are reviewed. The importance of identification of stem cells using functional as well as phenotypic markers is discussed. The novel field of nanotechnology is then discussed...... in the context of stem cell tracking in vivo. This review concludes with a section on the unexpected potential of bone marrow-derived stem cells to contribute to the repair of damaged tissues. The contribution of cell fusion to explain the latter phenomenon is discussed. SUMMARY: Because of exciting discoveries...

Large-scale multiplex polymerase chain reaction assay for diagnosis of viral reactivations after allogeneic hematopoietic stem cell transplantation.

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Inazawa, Natsuko; Hori, Tsukasa; Hatakeyama, Naoki; Yamamoto, Masaki; Yoto, Yuko; Nojima, Masanori; Suzuki, Nobuhiro; Shimizu, Norio; Tsutsumi, Hiroyuki

2015-08-01

Viral reactivations following hematopoietic stem cell transplantation are thought to result from the breakdown of both cell-mediated and humoral immunity. As a result, many viruses could be reactivated individually or simultaneously. Using a multiplex polymerase chain reaction (PCR), we prospectively examined many kinds of viral DNAs at a time in 105 patients who underwent allogeneic hematopoietic stem cell transplantation. In total, 591 whole blood samples were collected weekly from pre- to 42 days post-transplantation and the following 13 viruses were tested; herpes simplex virus 1 (HSV-1), HSV-2, varicella-zoster virus (VZV), Epstein-Barr virus (EBV), cytomegalovirus (CMV), human herpes virus 6 (HHV-6), HHV-7, HHV-8, adenovirus, BK virus (BKV), JC virus (JCV), parvovirus B19, and hepatitis B virus (HBV). Several viral DNAs were detected in 12 patients before hematopoietic stem cell transplantation. The detection rate gradually increased after transplantation and peaked at 21 days. The most frequently detected virus was HHV-6 (n = 63; 60.0%), followed by EBV (n = 11; 10.5%), CMV (n = 11; 10.5%), and HHV-7 (n = 9; 8.6%). Adenovirus and HBV were each detected in one patient (1.0%). Detection of HHV-6 DNA was significantly more common among patients undergoing cord blood transplantation or with steroid treatment. EBV DNA tended to be more common in patients treated with anti-thymocyte globulin. Multiplex PCR was useful for detecting many viral reactivations after hematopoietic stem cell transplantation, simultaneously. Cord blood transplantation, steroid treatment, or anti-thymocyte globulin use was confirmed to be risk factors after transplantation. © 2015 Wiley Periodicals, Inc.

Hematopoietic stem cell development requires transient Wnt/β-catenin activity

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Ruiz-Herguido, Cristina; Guiu, Jordi; D'Altri, Teresa

2012-01-01

in the aorta-gonad-mesonephros (AGM) region. We show here that β-catenin is nuclear and active in few endothelial nonhematopoietic cells closely associated with the emerging hematopoietic clusters of the embryonic aorta during mouse development. Importantly, Wnt/β-catenin activity is transiently required...... of mutant cells toward the hematopoietic lineage; however, these mutant cells still contribute to the adult endothelium. Together, those findings indicate that Wnt/β-catenin activity is needed for the emergence but not the maintenance of HSCs in mouse embryos....

Sodium Caseinate (CasNa) Induces Mobilization of Hematopoietic Stem Cells in a BALB/c Mouse Model.

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Santiago-Osorio, Edelmiro; Ledesma-Martínez, Edgar; Aguiñiga-Sánchez, Itzen; Poblano-Pérez, Ignacio; Weiss-Steider, Benny; Montesinos-Montesinos, Juan José; Mora-García, María de Lourdes

2015-09-25

BACKGROUND Hematopoietic stem cells transplantation has high clinical potential against a wide variety of hematologic, metabolic, and autoimmune diseases and solid tumors. Clinically, hematopoietic stem cells derived from peripheral blood are currently used more than those obtained from sources such as bone marrow. However, mobilizing agents used in the clinic tend to fail in high rates, making the number of mobilized cells insufficient for transplantation. We investigated whether sodium caseinate induces functional mobilization of hematopoietic stem cells into peripheral blood of Balb/c mice. MATERIAL AND METHODS Using a mouse model, we administrated sodium caseinate or Plerixafor, a commercial mobilizing agent, and analyzed counts of hematopoietic stem cells in peripheral blood, and then cells were transplanted into lethally irradiated mice to restore hematopoiesis. All assays were performed at least twice. RESULTS We found that sodium caseinate increases the number of mononuclear cells in peripheral blood with the immunophenotype of hematopoietic stem cells (0.2 to 0.5% LSK cells), allowing them to form colonies of various cell lineages in semisolid medium (psodium caseinate as a mobilizer of hematopoietic stem cells and its potential clinical application in transplantation settings.

Induction of various immune modulatory molecules in CD34(+) hematopoietic cells

DEFF Research Database (Denmark)

Umland, Oliver; Heine, Holger; Miehe, Michaela

2004-01-01

revealed that T cell proliferation can be induced by TNF-alpha-stimulated KG-1a cells, which is preventable by blocking anti-ICAM-1 monoclonal antibodies. Our results demonstrate that CD34(+) HCs have the potential to express a variety of immune-regulatory mediators upon stimulation by inflammatory......Lipopolysaccharide (LPS) has been shown to induce proliferation of human T-lymphocytes only in the presence of monocytes and CD34(+) hematopoietic cells (HCs) from peripheral blood. This finding provided evidence of an active role of CD34(+) HCs during inflammation and immunological events....... To investigate mechanisms by which CD34(+) HCs become activated and exert their immune-modulatory function, we used the human CD34(+) acute myeloid leukemia cell line KG-1a and CD34(+) bone marrow cells (BMCs). We showed that culture supernatants of LPS-stimulated mononuclear cells (SUP(LPS)) as well as tumor...

Total Hip Arthroplasty in Patients With Avascular Necrosis After Hematopoietic Stem Cell Transplantation.

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Vijapura, Anita; Levine, Harlan B; Donato, Michele; Hartzband, Mark A; Baker, Melissa; Klein, Gregg R

2018-03-01

The immunosuppressive regimens required for hematopoietic stem cell transplantation predispose recipients to complications, including avascular necrosis. Cancer-related comorbidities, immunosuppression, and poor bone quality theoretically increase the risk for perioperative medical complications, infection, and implant-related complications in total joint arthroplasty. This study reviewed 20 primary total hip arthroplasties for avascular necrosis in 14 patients. Outcomes were assessed at routine clinical visits and Harris hip scores were calculated. Follow-up radiographs were evaluated for component malposition, loosening, polyethylene wear, and osteolysis. Average follow-up was 44.5 months for all patients. Postoperative clinical follow-up revealed good to excellent outcomes, with significant improvement in functional outcome scores. There were no periprosthetic infections or revisions for aseptic loosening. There was 1 dislocation on postoperative day 40, which was treated successfully with a closed reduction. Two patients with a prior history of venous thromboembolism developed a pulmonary embolus on postoperative day 13 and 77, respectively. Four patients died several months to years after arthroplasty of complications unrelated to the surgical procedure. Total hip arthroplasty can both be safely performed and greatly improve quality of life in recipients of hematopoietic stem cell transplantation who develop avascular necrosis. However, prolonged venous thromboembolism prophylaxis should be carefully considered in this high-risk patient population. [Orthopedics. 2018; 41(2):e257-e261.]. Copyright 2018, SLACK Incorporated.

Mismatch repair deficient hematopoietic stem cells are preleukemic stem cells.

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Yulan Qing

Full Text Available Whereas transformation events in hematopoietic malignancies may occur at different developmental stages, the initial mutation originates in hematopoietic stem cells (HSCs, creating a preleukemic stem cell (PLSC. Subsequent mutations at either stem cell or progenitor cell levels transform the PLSC into lymphoma/leukemia initiating cells (LIC. Thymic lymphomas have been thought to develop from developing thymocytes. T cell progenitors are generated from HSCs in the bone marrow (BM, but maturation and proliferation of T cells as well as T-lymphomagenesis depends on both regulatory mechanisms and microenvironment within the thymus. We studied PLSC linked to thymic lymphomas. In this study, we use MSH2-/- mice as a model to investigate the existence of PLSC and the evolution of PLSC to LIC. Following BM transplantation, we found that MSH2-/- BM cells from young mice are able to fully reconstitute multiple hematopoietic lineages of lethally irradiated wild-type recipients. However, all recipients developed thymic lymphomas within three and four months post transplantation. Transplantation of different fractions of BM cells or thymocytes from young health MSH2-/- mice showed that an HSC enriched fraction always reconstituted hematopoiesis followed by lymphoma development. In addition, lymphomas did not occur in thymectomized recipients of MSH2-/- BM. These results suggest that HSCs with DNA repair defects such as MSH2-/- are PLSCs because they retain hematopoietic function, but also carry an obligate lymphomagenic potential within their T-cell progeny that is dependent on the thymic microenvironment.

Early CD3+/CD15+ peripheral blood leukocyte chimerism patterns correlate with long-term engraftment in non-malignant hematopoietic SCT.

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Ketterl, T G; Flesher, M; Shanley, R; Miller, W

2014-04-01

Following hematopoietic SCT (HSCT) for non-malignant disorders (NMDs) variable donor chimerism among lympho-hematopoietic lines may be observed. We retrospectively evaluated early post-HSCT, lineage-sorted (CD3+ and CD15+) peripheral blood leukocyte chimerism data to characterize patterns and assess for association with long-term CD15+ engraftment. 'Early' was defined as the first value obtained between days +14 and +42, 'late' as the last recorded value after day +90. 'High' donor chimerism was defined as 80% on either fraction at all time-points. Patients were classified into four subgroups with respect to early CD3+/CD15+ chimerism patterns (high/low) then analyzed for long-term CD15+ chimerism status. A total of 135 transplants were evaluable, with all three time-points available in 97. Underlying disease, graft source, patient age and conditioning intensity varied. 'Split' early chimerism (discordant high/low CD3+/CD15+ status) was common. Multivariable analysis revealed strong association between conditioning regimen and primary disease on early CD3+/CD15+ chimerism patterns and a dominant predictive effect of early CD15+ chimerism on long-term CD15+ donor engraftment (observed at median day +365). These data may guide real-time clinician decisions (restraint vs intervention, when available) when faced with unfavorable or unusual early lympho-hematopoietic chimerism patterns following HSCT for NMD.

Factors related to resistance to hematopoietic death in mice

International Nuclear Information System (INIS)

Mori, Nobuko; Okumoto, Masaaki; Yonezawa, Morio; Nishikawa, Ryosuke; Takamori, Yasuhiko; Esaki, Kozaburo.

1994-01-01

Mouse strain difference in the radiosensitivity to hematopoietic death is thought to be determined by several factors besides radiosensitivity and the initial number of hematopoietic stem cells. Factors related to the survival of mice exposed to X-irradiation were analyzed using BALB/cHeA and STS/A strains whose LD 50/30 values differ markedly (BALB/cHeA, 5.55 Gy; STS/A, 8.45 Gy). STS/A mice exposed to 4 Gy of X-irradiation showed a small reduction but rapid recovery of blood cells (leukocytes, erythrocytes, and thrombocytes) when compared with BALB/cHeA mice. The survival of endogenous and exogenous CFU-S was much higher, by a magnitude of one log or more, in STS/A mice than those in BALB/cHeA mice; whereas the initial numbers of femoral CFU-S were similar for the two strains. The recovery of exogenous CFU-S was much more rapid in STS/A mice than it was in BALB/cHeA mice after 4 Gy of X-irradiation. Furthermore, spleen colonies produced by the transfusion of STS/A marrow cells into syngeneic recipients were significantly larger than those produced by BALB/cHeA marrow cells, regardless of whether the mice used for sources of marrow cells had been irradiated. But, there was no such difference when unirradiated marrow cells from the two strains were transfused into (BALB/cHeA X STS/A) F 1 recipients. These results indicate the possible contribution of a host factor (s) that stimulates the growth of spleen colonies after radiation to the radioresistance of STS/A mice, in addition to the primary effect of higher number of survivals of endogenous and exogenous CFU-S in STS/A mice. (author)

EDAG promotes the expansion and survival of human CD34+ cells.

Directory of Open Access Journals (Sweden)

Ke Zhao

Full Text Available EDAG is multifunctional transcriptional regulator primarily expressed in the linloc-kit+Sca-1+ hematopoietic stem cells (HSC and CD34+ progenitor cells. Previous studies indicate that EDAG is required for maintaining hematopoietic lineage commitment balance. Here using ex vivo culture and HSC transplantation models, we report that EDAG enhances the proliferative potential of human cord blood CD34+ cells, increases survival, prevents cell apoptosis and promotes their repopulating capacity. Moreover, EDAG overexpression induces rapid entry of CD34+ cells into the cell cycle. Gene expression profile analysis indicate that EDAG knockdown leads to down-regulation of various positive cell cycle regulators including cyclin A, B, D, and E. Together these data provides novel insights into EDAG in regulation of expansion and survival of human hematopoietic stem/progenitor cells.

Risk of Hematopoietic and Lymphoproliferative Malignancies among U. S. Radiologic Technologists

International Nuclear Information System (INIS)

Linet, M. S.; Fredman, D. M.; Mohan, A.; Morin Doody, M.; Ron, E.; Mabuchi, K.; Alexander, B. B.; Sigurdson, A.; Matanoski, G.; Hauptmann, M.

2004-01-01

To evaluate risks of hematopoietic and lymphoproliferative malignancies among medical workers exposed to protracted low-to-moderate-dose radiation exposures, a follow-up investigation was conducted in a nation wide cohort of U. S. radiologic technologists. eligible for this study were 71.894 technologists (78% female) certified for at least 2 years during 1926-82, who had responded to a baseline mail questionnaire during 1983-89, were cancer-free except for non-melanoma skin cancer at completion of the questionnaire, and completed a second questionnaire during 1994-98 or died through August 1998. There were 241 technologists with hematopoietic or lymphoproliferative malignancies, including 41 with leukemia subtypes associated with radiation exposures (specifically acute myeloid, acute lymphoid and chronic myeloid leukemias, hereafter designated radiogenic leukemias), 23 with chronic lymphocytic leukemia, 28 with multiple myeloma, 118 with non-Hodgkin lymphoma, and 31 with Hodgkin lymphoma. Of the 241 hematopoietic or lymphoproliferative malignancies identified among radiologic technologists, 85 percent were confirmed by medical records or death certificates, including 98 percent of radiogenic leukemia. Risks of the hematopoietic or lymphoproliferative malignancies were evaluated in relation to questionnaire-derived information on employment as a radiologic technologist, including procedures, work practices, and protective measures. cox proportional hazards regression analysis was used to compute relative risks and 95% confidence intervals, using age at diagnosis as the response, stratifying at baseline for birth cohort in 5-year intervals, and adjusting for potential confounding. Risks were not increased for any of the hematopoietic or lymphoproliferative neoplasms according to year first worked or total duration of years worked as radiologic technologist. For the combined radiogenic leukemias, risks rose significantly with an increasing number of years worked

Protracted radiation-induced alterations in hematopoietic repair and recovery

International Nuclear Information System (INIS)

Seed, T.M.; Fritz, T.E.

1997-01-01

Pathologic predisposition of beagle dogs under chronic, low daily dose (7.5 cGy day -1 ) whole-body gamma irradiation has been studied relative to molecular repair and hematopoietic competency. Molecular repair, assessed by a microscopy-based unscheduled DNA synthesis (UDS) response, was measured within proliferative and nonproliferative marrow myeloid elements of dogs with markedly different hematopoietic capacities (low capacity, aplasia-prone [AA + ] versus high capacity, myeloproliferative disease-prone [MPD + ]) under protracted radiation stress. Results indicated that protracted exposure elicited a net increase in UDS-repair capacity that was largely independent of exposure duration. This enhanced capacity resulted from the increased strength of the UDS signal together with an expanded number of positively responding cells. The combined response was strong in primitive blasts and weak in more differentiated myelocytic cells. The UDS repair response of the MPD + dogs was significantly greater than that of the AA + animals and was clearly modified relative to the controls. These results suggest that both resiliency and pathologic potential of the hematopoietic system under protracted radiation stress is, in part, associated with an augmentable DNA repair within the more primitive myeloid marrow elements. (author)

Cell cycle regulation of hematopoietic stem or progenitor cells.

Science.gov (United States)

Hao, Sha; Chen, Chen; Cheng, Tao

2016-05-01

The highly regulated process of blood production is achieved through the hierarchical organization of hematopoietic stem cell (HSC) subsets and their progenies, which differ in self-renewal and differentiation potential. Genetic studies in mice have demonstrated that cell cycle is tightly controlled by the complex interplay between extrinsic cues and intrinsic regulatory pathways involved in HSC self-renewal and differentiation. Deregulation of these cellular programs may transform HSCs or hematopoietic progenitor cells (HPCs) into disease-initiating stem cells, and can result in hematopoietic malignancies such as leukemia. While previous studies have shown roles for some cell cycle regulators and related signaling pathways in HSCs and HPCs, a more complete picture regarding the molecular mechanisms underlying cell cycle regulation in HSCs or HPCs is lacking. Based on accumulated studies in this field, the present review introduces the basic components of the cell cycle machinery and discusses their major cellular networks that regulate the dormancy and cell cycle progression of HSCs. Knowledge on this topic would help researchers and clinicians to better understand the pathogenesis of relevant blood disorders and to develop new strategies for therapeutic manipulation of HSCs.

Herpes zoster-associated voiding dysfunction in hematopoietic malignancy patients.

Science.gov (United States)

Imafuku, Shinichi; Takahara, Masakazu; Uenotsuchi, Takeshi; Iwato, Koji; Furue, Masutaka

2008-01-01

Voiding dysfunction is a rare but important complication of lumbo-sacral herpes zoster. Although the symptoms are transient, the clinical impact on immunocompromised patients cannot be overlooked. To clarify the time course of voiding dysfunction in herpes zoster, 13 herpes zoster patients with voiding dysfunction were retrospectively analyzed. Of 13 patients, 12 had background disease, and six of these were hematopoietic malignancies; four of these patients were hematopoietic stem cell transplant (HSCT) recipients. Ten patients had sacral lesions, two had lumbar, and one had thoracic lesions. Interestingly, patients with severe rash, or with hematopoietic malignancy had later onset of urinary retention than did patients with mild skin symptoms (Mann-Whitney U analysis, P = 0.053) or with other background disease (P = 0.0082). Patients with severe skin rash also had longer durations (P = 0.035). In one case, acute urinary retention occurred as late as 19 days after the onset of skin rash. In immune compromised subjects, attention should be paid to patients with herpes zoster in the lumbo-sacral area for late onset of acute urinary retention even after the resolution of skin symptoms.

The impact of HLA matching on long-term transplant outcome after allogeneic hematopoietic stem cell transplantation for CLL: a retrospective study from the EBMT registry.

NARCIS (Netherlands)

Michallet, M.; Sobh, M.; Milligan, D.; Morisset, S.; Niederwieser, D.; Koza, V.; Ruutu, T.; Russell, N.H.; Verdonck, L.; Dhedin, N.; Vitek, A.; Boogaerts, M.; Vindelov, L.; Finke, J.; Dubois, V.; Biezen, A. van; Brand, R.; Witte, T.J.M. de; Dreger, P.

2010-01-01

We analyzed 368 chronic lymphocytic leukemia patients who underwent allogeneic hematopoietic stem cell transplantation reported to the EBMT registry between 1995 and 2007. There were 198 human leukocyte antigen (HLA)-identical siblings; among unrelated transplants, 31 were well matched in high

Evaluation of perfluoroalkyl acid activity using primary mouse and human hepatocytes

International Nuclear Information System (INIS)

Rosen, Mitchell B.; Das, Kaberi P.; Wood, Carmen R.; Wolf, Cynthia J.; Abbott, Barbara D.; Lau, Christopher

2013-01-01

While perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) have been studied at length, less is known about the biological activity of other perfluoroalkyl acids (PFAAs) detected in the environment. Using a transient transfection assay developed in COS-1 cells, our group has previously evaluated a variety of PFAAs for activity associated with activation of peroxisome proliferator-activated receptor alpha (PPARα). Here we use primary heptatocytes to further assess the biological activity of a similar group of PFAAs using custom designed Taqman Low Density Arrays. Primary mouse and human hepatoyctes were cultured for 48 h in the presence of varying concentrations of 12 different PFAAs or Wy14,643, a known activator of PPARα. Total RNA was collected and the expression of 48 mouse or human genes evaluated. Gene selection was based on either in-house liver microarray data (mouse) or published data using primary hepatocytes (human). Gene expression in primary mouse hepatocytes was more restricted than expected. Genes typically regulated in whole tissue by PPARα agonists were not altered in mouse cells including Acox1, Me1, Acaa1a, Hmgcs1, and Slc27a1. Cyp2b10, a gene regulated by the constitutive androstane receptor and a transcript normally up-regulated by in vivo exposure to PFAAs, was also unchanged in cultured mouse hepatocytes. Cyp4a14, Ehhadh, Pdk4, Cpt1b, and Fabp1 were regulated as expected in mouse cells. A larger group of genes were differentially expressed in human primary hepatocytes, however, little consistency was observed across compounds with respect to which genes produced a significant dose response making the determination of relative biological activity difficult. This likely reflects weaker activation of PPARα in human versus rodent cells as well as variation among individual cell donors. Unlike mouse cells, CYP2B6 was up-regulated in human hepatocytes by a number of PFAAs as was PPARδ. Rankings were conducted on the limited

Serpina1 is a potent inhibitor of IL-8-induced hematopoietic stem cell mobilization

NARCIS (Netherlands)

van Pel, M; van Os, R; Velders, GA; Hagoort, H; Heegaard, PMH; Lindley, IJD; Willemze, R; Fibbe, WE

2006-01-01

Here, we report that cytokine-induced (granulocyte colony-stimulating factor and IL-8) hematopoietic stem cell (HSC) and hematopoietic progenitor cell (HPC) mobilization is completely inhibited after low-dose (0.5 Gy) total-body irradiation (TBI). Because neutrophil granular proteases are regulatory

Serpina1 is a potent inhibitor of IL-8-induced hematopoietic stem cell mobilization

DEFF Research Database (Denmark)

van Pel, M.; van Os, R.; Velders, G.A.

2006-01-01

Here, we report that cytokine-induced (granulocyte colony-stimulating factor and IL-8) hematopoietic stem cell (HSC) and hematopoietic progenitor cell (HPC) mobilization is completely inhibited after low-dose (0.5 Gy) total-body irradiation (TBI). Because neutrophil granular proteases are regulat...

Cellular memory and, hematopoietic stem cell aging

NARCIS (Netherlands)

Kamminga, Leonie M.; de Haan, Gerald

Hematopoietic stem cells (HSCs) balance self-renewal and differentiation in order to sustain lifelong blood production and simultaneously maintain the HSC pool. However, there is clear evidence that HSCs are subject to quantitative and qualitative exhaustion. In this review, we briefly discuss

Hematopoietic stem cell transplantation in multiple sclerosis

DEFF Research Database (Denmark)

Rogojan, C; Frederiksen, J L

2009-01-01

Intensive immunosuppresion followed by hematopoietic stem cell transplantation (HSCT) has been suggested as potential treatment in severe forms of multiple sclerosis (MS). Since 1995 ca. 400 patients have been treated with HSCT. Stabilization or improvement occurred in almost 70% of cases at least...

Proliferative capacity of murine hematopoietic stem cells

International Nuclear Information System (INIS)

Hellman, S.; Botnick, L.E.; Hannon, E.C.; Vigneulle, R.M.

1978-01-01

The present study demonstrates a decrease in self-renewal capacity with serial transfer of murine hematopoietic stem cells. Production of differentiated cell progeny is maintained longer than stem cell self-renewal. In normal animals the capacity for self-renewal is not decreased with increasing donor age. The stem cell compartment in normal animals, both young and old, appears to be proliferatively quiescent. After apparent recovery from the alkylating agent busulfan, the probability of stem cell self-renewal is decreased, there is a permanent defect in the capacity of the bone marrow for serial transplantation, and the stem cells are proliferatively active. These findings support a model of the hematopoietic stem cell compartment as a continuum of cells with decreasing capacities for self-renewal, increasing likelihood for differentiation, and increasing proliferative activity. Cells progress in the continuum in one direction and such progression is not reversible

Molecular Characterization of the Interactions between Vascular Selectins and Glycoprotein Ligands on Human Hematopoietic Stem/Progenitor Cells

KAUST Repository

Abusamra, Dina

2016-12-01

The human bone marrow vasculature constitutively expresses both E-selectin and P-selectin where they interact with the cell-surface glycan moiety, sialyl Lewis x, on circulating hematopoietic stem/progenitor cells (HSPCs) to mediate the essential tethering/rolling step. Although several E-selectin glycoprotein ligands (E-selLs) have been identified, the importance of each E-selL on human HSPCs is debatable and requires additional methodologies to advance their specific involvement. The first objective was to fill the knowledge gap in the in vitro characterization of the mechanisms used by selectins to mediate the initial step in the HSPCs homing by developing a real time immunoprecipitation-based assay on a surface plasmon resonance chip. This novel assay bypass the difficulties of purifying ligands, enables the use of natively glycosylated forms of selectin ligands from any model cell of interest and study its binding affinities under flow. We provide the first comprehensive quantitative binding kinetics of two well-documented ligands, CD44 and PSGL-1, with E-selectin. Both ligands bind monomeric E-selectin transiently with fast on- and off-rates while they bind dimeric E-selectin with remarkably slow on- and off-rates with the on-rate, but not the off-rate, is dependent on salt concentration. Thus, suggest a mechanism through which monomeric selectins mediate initial fast-on and -off binding to capture the circulating cells out of shear-flow; subsequently, tight binding by dimeric/oligomeric selectins is enabled to slow rolling significantly. The second objective is to fully identify and characterize E/P-selectin ligand candidates expressed on CD34+ HSPCs which cause enhanced migration after intravenous transplantation compared to their CD34- counterparts. CD34 is widely recognized marker of human HSPCs but its natural ligand and function on these cells remain elusive. Proteomics identified CD34 as an E-selL candidate on human HSPCs, whose binding to E

Fine-tuning Hematopoiesis: Microenvironmental factors regulating self-renewal and differentiation of hematopoietic stem cells

NARCIS (Netherlands)

T.C. Luis (Tiago)

2010-01-01

markdownabstract__Abstract__ Hematopoietic stem cells (HSCs) have the ability to self renew and generate all lineages of blood cells. Although it is currently well established that hematopoietic stem cells (HSCs) regenerate the blood compartment, it was only in the 1960s that was introduced the

The role of growth differentiation factor 15 in the pathogenesis of primary myelofibrosis

International Nuclear Information System (INIS)

Uchiyama, Tatsuki; Kawabata, Hiroshi; Miura, Yasuo; Yoshioka, Satoshi; Iwasa, Masaki; Yao, Hisayuki; Sakamoto, Soichiro; Fujimoto, Masakazu; Haga, Hironori; Kadowaki, Norimitsu; Maekawa, Taira; Takaori-Kondo, Akifumi

2015-01-01

Growth differentiation factor 15 (GDF15) is a pleiotropic cytokine that belongs to the transforming growth factor-β superfamily. Elevated serum concentrations of this cytokine have been reported in patients with various malignancies. To assess the potential roles of GDF15 in hematologic malignancies, we measured its serum levels in patients with these diseases. We found that serum GDF15 levels were elevated in almost all these patients, particularly in patients with primary myelofibrosis (PMF). Immunohistochemical staining of bone marrow (BM) specimens revealed that GDF15 was strongly expressed by megakaryocytes, which may be sources of increased serum GDF15 in PMF patients. Therefore, we further assessed the contribution of GDF15 to the pathogenesis of PMF. Recombinant human (rh) GDF15 enhanced the growth of human BM mesenchymal stromal cells (BM-MSCs), and it enhanced the potential of these cells to support human hematopoietic progenitor cell growth in a co-culture system. rhGDF15 enhanced the growth of human primary fibroblasts, but it did not affect their expression of profibrotic genes. rhGDF15 induced osteoblastic differentiation of BM-MSCs in vitro, and pretreatment of BM-MSCs with rGDF15 enhanced the induction of bone formation in a xenograft mouse model. These results suggest that serum levels of GDF15 in PMF are elevated, that megakaryocytes are sources of this cytokine in BM, and that GDF15 may modulate the pathogenesis of PMF by enhancing proliferation and promoting osteogenic differentiation of BM-MSCs

Investigation of radioprotective effect of indraline of hematopoietic system in different species of animal

International Nuclear Information System (INIS)

Vasin, M.V.; Antipov, V.V.; Chernov, G.A.

1996-01-01

The experiments were made on mice, guinea pigs and dogs. Radioprotector indraline increased radioresistant state of hematopoietic stem cells in vivo and in vitro, decreased the amount of post-radiation chromosome aberrations in marrow, induced more early and intensive post-radiation proliferative repair of marrow and spleen, faster regeneration of the initial amount of leukocytes thrombocytes and erytrocytes in blood of mice, guinea pigs and dogs. Antiradiation efficiency of indraline in hematopoietic system is equal to 1.5-2 by FMD. Radioprotective mechanism of indraline effect on hematopoietic system is discussed. 22 refs.; 8 figs.; 4 tabs

The impact of HLA matching on long-term transplant outcome after allogeneic hematopoietic stem cell transplantation for CLL: a retrospective study from the EBMT registry

DEFF Research Database (Denmark)

Michallet, M; Sobh, M; Milligan, D

2010-01-01

We analyzed 368 chronic lymphocytic leukemia patients who underwent allogeneic hematopoietic stem cell transplantation reported to the EBMT registry between 1995 and 2007. There were 198 human leukocyte antigen (HLA)-identical siblings; among unrelated transplants, 31 were well matched in high re...

Endothelial jagged-2 sustains hematopoietic stem and progenitor reconstitution after myelosuppression.

Science.gov (United States)

Guo, Peipei; Poulos, Michael G; Palikuqi, Brisa; Badwe, Chaitanya R; Lis, Raphael; Kunar, Balvir; Ding, Bi-Sen; Rabbany, Sina Y; Shido, Koji; Butler, Jason M; Rafii, Shahin

2017-12-01

Angiocrine factors, such as Notch ligands, supplied by the specialized endothelial cells (ECs) within the bone marrow and splenic vascular niche play an essential role in modulating the physiology of adult hematopoietic stem and progenitor cells (HSPCs). However, the relative contribution of various Notch ligands, specifically jagged-2, to the homeostasis of HSPCs is unknown. Here, we show that under steady state, jagged-2 is differentially expressed in tissue-specific vascular beds, but its expression is induced in hematopoietic vascular niches after myelosuppressive injury. We used mice with EC-specific deletion of the gene encoding jagged-2 (Jag2) to demonstrate that while EC-derived jagged-2 was dispensable for maintaining the capacity of HSPCs to repopulate under steady-state conditions, by activating Notch2 it did contribute to the recovery of HSPCs in response to myelosuppressive conditions. Engraftment and/or expansion of HSPCs was dependent on the expression of endothelial-derived jagged-2 following myeloablation. Additionally, jagged-2 expressed in bone marrow ECs regulated HSPC cell cycle and quiescence during regeneration. Endothelial-deployed jagged-2 triggered Notch2/Hey1, while tempering Notch2/Hes1 signaling in HSPCs. Collectively, these data demonstrate that EC-derived jagged-2 activates Notch2 signaling in HSPCs to promote hematopoietic recovery and has potential as a therapeutic target to accelerate balanced hematopoietic reconstitution after myelosuppression.

DNA Damage: A Sensible Mediator of the Differentiation Decision in Hematopoietic Stem Cells and in Leukemia

Directory of Open Access Journals (Sweden)

Cary N. Weiss

2015-03-01

Full Text Available In the adult, the source of functionally diverse, mature blood cells are hematopoietic stem cells, a rare population of quiescent cells that reside in the bone marrow niche. Like stem cells in other tissues, hematopoietic stem cells are defined by their ability to self-renew, in order to maintain the stem cell population for the lifetime of the organism, and to differentiate, in order to give rise to the multiple lineages of the hematopoietic system. In recent years, increasing evidence has suggested a role for the accumulation of reactive oxygen species and DNA damage in the decision for hematopoietic stem cells to exit quiescence and to differentiate. In this review, we will examine recent work supporting the idea that detection of cell stressors, such as oxidative and genetic damage, is an important mediator of cell fate decisions in hematopoietic stem cells. We will explore the benefits of such a system in avoiding the development and progression of malignancies, and in avoiding tissue exhaustion and failure. Additionally, we will discuss new work that examines the accumulation of DNA damage and replication stress in aging hematopoietic stem cells and causes us to rethink ideas of genoprotection in the bone marrow niche.

Four stages of hepatic hematopoiesis in human embryos and fetuses.

Science.gov (United States)

Fanni, D; Angotzi, F; Lai, F; Gerosa, C; Senes, G; Fanos, V; Faa, G

2018-03-01

The liver is a major hematopoietic organ during embryonic and fetal development in humans. Its hematopoietic activity starts during the first weeks of gestation and continues until birth. During this period the liver is colonized by undifferentiated hematopoietic stem cells (HSCs) that gradually differentiate and once mature, enter the circulatory system through the hepatic sinusoids, this process is called hepatic hematopoiesis. The morphology of hepatic hematopoiesis, has been studied in humans through the years, and led to a characterization of all the cell types that make up these phenomena. Studies on murine models also helped to describe the extent of hepatic hematopoiesis at different gestational ages. Using this knowledge, we attempted to describe how hepatic hematopoiesis morphologically evolves as gestation progresses, in human embryos and fetuses. Thus, we observed a total of 32 tissue specimens obtained from the livers of embryos and fetuses at different gestational ages. Basing our observations on the four stages of liver hematopoiesis identified by Sasaki and Sonoda in mice, we also described four consecutive stages of liver hematopoiesis in humans, which resulted to be highly similar to those described in murine models.

Vision first? The development of primary visual cortical networks is more rapid than the development of primary motor networks in humans.

Directory of Open Access Journals (Sweden)

Patricia Gervan

Full Text Available The development of cortical functions and the capacity of the mature brain to learn are largely determined by the establishment and maintenance of neocortical networks. Here we address the human development of long-range connectivity in primary visual and motor cortices, using well-established behavioral measures--a Contour Integration test and a Finger-tapping task--that have been shown to be related to these specific primary areas, and the long-range neural connectivity within those. Possible confounding factors, such as different task requirements (complexity, cognitive load are eliminated by using these tasks in a learning paradigm. We find that there is a temporal lag between the developmental timing of primary sensory vs. motor areas with an advantage of visual development; we also confirm that human development is very slow in both cases, and that there is a retained capacity for practice induced plastic changes in adults. This pattern of results seems to point to human-specific development of the "canonical circuits" of primary sensory and motor cortices, probably reflecting the ecological requirements of human life.

Autocrine stimulation of VEGFR-2 activates human leukemic cell growth and migration

Science.gov (United States)

Dias, Sergio; Hattori, Koichi; Zhu, Zhenping; Heissig, Beate; Choy, Margaret; Lane, William; Wu, Yan; Chadburn, Amy; Hyjek, Elizabeth; Gill, Muhammad; Hicklin, Daniel J.; Witte, Larry; Moore, M.A.S.; Rafii, Shahin

2000-01-01

Emerging data suggest that VEGF receptors are expressed by endothelial cells as well as hematopoietic stem cells. Therefore, we hypothesized that functional VEGF receptors may also be expressed in malignant counterparts of hematopoietic stem cells such as leukemias. We demonstrate that certain leukemias not only produce VEGF but also express functional VEGFR-2 in vivo and in vitro, resulting in the generation of an autocrine loop that may support leukemic cell survival and proliferation. Approximately 50% of freshly isolated leukemias expressed mRNA and protein for VEGFR-2. VEGF165 induced phosphorylation of VEGFR-2 and increased proliferation of leukemic cells, demonstrating these receptors were functional. VEGF165 also induced the expression of MMP-9 by leukemic cells and promoted their migration through reconstituted basement membrane. The neutralizing mAb IMC-1C11, specific to human VEGFR-2, inhibited leukemic cell survival in vitro and blocked VEGF165-mediated proliferation of leukemic cells and VEGF-induced leukemic cell migration. Xenotransplantation of primary leukemias and leukemic cell lines into immunocompromised nonobese diabetic mice resulted in significant elevation of human, but not murine, VEGF in plasma and death of inoculated mice within 3 weeks. Injection of IMC-1C11 inhibited proliferation of xenotransplanted human leukemias and significantly increased the survival of inoculated mice. Interruption of signaling by VEGFRs, particularly VEGFR-2, may provide a novel strategy for inhibiting leukemic cell proliferation. PMID:10953026

Aging, Clonality and Rejuvenation of Hematopoietic Stem Cells

Science.gov (United States)

Akunuru, Shailaja; Geiger, Hartmut

2016-01-01

Aging is associated with reduced organ function and increased disease incidence. Hematopoietic stem cell (HSC) aging driven by both cell intrinsic and extrinsic factors is linked to impaired HSC self-renewal and regeneration, aging-associated immune remodeling, and increased leukemia incidence. Compromised DNA damage responses and increased production of reactive oxygen species have been previously causatively attributed to HSC aging. However, recent paradigm-shifting concepts such as global epigenetic and cytoskeletal polarity shifts, cellular senescence, as well as clonal selection of HSCs upon aging provide new insights into HSC aging mechanisms. Rejuvenating agents that can reprogram the epigenetic status of aged HSCs or senolytic drugs that selectively deplete senescent cells provide promising translational avenues for attenuating hematopoietic aging and potentially, alleviating aging-associated immune remodeling and myeloid malignancies. PMID:27380967

Cellular radiosensitivity and DNA damage in primary human fibroblasts

International Nuclear Information System (INIS)

Wurm, R.; Burnet, N.G.; Duggal, N.

1994-01-01

To evaluate the relationship between radiation-induced cell survival and DNA damage in primary human fibroblasts to decide whether the initial or residual DNA damage levels are more predictive of normal tissue cellular radiosensitivity. Five primary human nonsyndromic and two primary ataxia telangiectasia fibroblast strains grown in monolayer were studied. Cell survival was assessed by clonogenic assay. Irradiation was given at high dose rate (HDR) 1-2 Gy/min. DNA damage was measured in stationary phase cells and expressed as fraction released from the well by pulsed-field gel electrophoresis (PFGE). For initial damage, cells were embedded in agarose and irradiated at HDR on ice. Residual DNA damage was measured in monolayer by allowing a 4-h repair period after HDR irradiation. Following HDR irradiation, cell survival varied between SF 2 0.025 to 0.23. Measurement of initial DNA damage demonstrated linear induction up to 30 Gy, with small differences in the slope of the dose-response curve between strains. No correlation between cell survival and initial damage was found. Residual damage increased linearly up to 80 Gy with a variation in slope by a factor of 3.2. Cell survival correlated with the slope of the dose-response curves for residual damage of the different strains (p = 0.003). The relationship between radiation-induced cell survival and DNA damage in primary human fibroblasts of differing radiosensitivity is closest with the amount of DNA damage remaining after repair. If assays of DNA damage are to be used as predictors of normal tissue response to radiation, residual DNA damage provides the most likely correlation with cell survival. 52 refs., 5 figs., 2 tabs

Genetic modification of hematopoietic stem cells with nonviral systems: past progress and future prospects.

Science.gov (United States)

Papapetrou, E P; Zoumbos, N C; Athanassiadou, A

2005-10-01

Serious unwanted complications provoked by retroviral gene transfer into hematopoietic stem cells (HSCs) have recently raised the need for the development and assessment of alternative gene transfer vectors. Within this context, nonviral gene transfer systems are attracting increasing interest. Their main advantages include low cost, ease of handling and large-scale production, large packaging capacity and, most importantly, biosafety. While nonviral gene transfer into HSCs has been restricted in the past by poor transfection efficiency and transient maintenance, in recent years, biotechnological developments are converting nonviral transfer into a realistic approach for genetic modification of cells of hematopoietic origin. Herein we provide an overview of past accomplishments in the field of nonviral gene transfer into hematopoietic progenitor/stem cells and we point at future challenges. We argue that episomally maintained self-replicating vectors combined with physical methods of delivery show the greatest promise among nonviral gene transfer strategies for the treatment of disorders of the hematopoietic system.

Regulation of Hematopoietic Cell Development and Function Through Phosphoinositides

Directory of Open Access Journals (Sweden)

Mila Elich

2018-05-01

Full Text Available One of the most paramount receptor-induced signal transduction mechanisms in hematopoietic cells is production of the lipid second messenger phosphatidylinositol(3,4,5trisphosphate (PIP3 by class I phosphoinositide 3 kinases (PI3K. Defective PIP3 signaling impairs almost every aspect of hematopoiesis, including T cell development and function. Limiting PIP3 signaling is particularly important, because excessive PIP3 function in lymphocytes can transform them and cause blood cancers. Here, we review the key functions of PIP3 and related phosphoinositides in hematopoietic cells, with a special focus on those mechanisms dampening PIP3 production, turnover, or function. Recent studies have shown that beyond “canonical” turnover by the PIP3 phosphatases and tumor suppressors phosphatase and tensin homolog (PTEN and SH2 domain-containing inositol-5-phosphatase-1 (SHIP-1/2, PIP3 function in hematopoietic cells can also be dampened through antagonism with the soluble PIP3 analogs inositol(1,3,4,5tetrakisphosphate (IP4 and inositol-heptakisphosphate (IP7. Other evidence suggests that IP4 can promote PIP3 function in thymocytes. Moreover, IP4 or the kinases producing it limit store-operated Ca2+ entry through Orai channels in B cells, T cells, and neutrophils to control cell survival and function. We discuss current models for how soluble inositol phosphates can have such diverse functions and can govern as distinct processes as hematopoietic stem cell homeostasis, neutrophil macrophage and NK cell function, and development and function of B cells and T cells. Finally, we will review the pathological consequences of dysregulated IP4 activity in immune cells and highlight contributions of impaired inositol phosphate functions in disorders such as Kawasaki disease, common variable immunodeficiency, or blood cancer.

MYSM1 Is Essential for Maintaining Hematopoietic Stem Cell (HSC) Quiescence and Survival.

Science.gov (United States)

Huo, Yi; Li, Bing-Yi; Lin, Zhi-Feng; Wang, Wei; Jiang, Xiao-Xia; Chen, Xu; Xi, Wen-Jin; Yang, An-Gang; Chen, Si-Yi; Wang, Tao

2018-04-25

BACKGROUND Histone H2A deubiquitinase MYSM1 has recently been shown to be essential for hematopoiesis and hematopoietic stem cell (HSC) function in both mice and humans. However, conventional MYSM1 knockouts cause partial embryonic lethality and growth retardation, and it is difficult to convincingly remove the effects of environmental factors on HSC differentiation and function. MATERIAL AND METHODS MYSM1 conditional knockout (cKO) mice were efficiently induced by using the Vav1-cre transgenic system. The Vav-Cre MYSM1 cKO mice were then analyzed to verify the intrinsic role of MYSM1 in hematopoietic cells. RESULTS MYSM1 cKO mice were viable and were born at normal litter sizes. At steady state, we observed a defect in hematopoiesis, including reduced bone marrow cellularity and abnormal HSC function. MYSM1 deletion drives HSCs from quiescence into rapid cycling, and MYSM1-deficient HSCs display impaired engraftment. In particular, the immature cycling cKO HSCs have elevated reactive oxygen species (ROS) levels and are prone to apoptosis, resulting in the exhaustion of the stem cell pool during stress response to 5-FU. CONCLUSIONS Our study using MYSM1 cKO mice confirms the important role of MYSM1 in maintaining HSC quiescence and survival.

Aryl hydrocarbon receptor activation by 2,3,7,8-tetrachlorodibenzo-p-dioxin impairs human B lymphopoiesis

International Nuclear Information System (INIS)

Li, Jinpeng; Phadnis-Moghe, Ashwini S.; Crawford, Robert B.; Kaminski, Norbert E.

2017-01-01

The homeostasis of peripheral B cell compartment requires lifelong B lymphopoiesis from hematopoietic stem cells (HSC). As a result, the B cell repertoire is susceptible to disruptions of hematopoiesis. Increasing evidence, primarily from rodent models, shows that the aryl hydrocarbon receptor (AHR) regulates hematopoiesis. To study the effects of persistent AHR activation on human B cell development, a potent AHR agonist and known environmental contaminant, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) was utilized. An in vitro B cell development model system was established by co-culturing human cord blood-derived HSCs with irradiated human primary bone marrow stromal cells. Using this in vitro model, we found that TCDD significantly suppressed the total number of hematopoietic stem and progenitor cells (HSPC) in a concentration-dependent manner. Cell death analysis demonstrated that the decrease in cell number was not due to cytotoxicity by TCDD. In addition, TCDD markedly decreased CD34 expression on HSPCs. Structure-activity relationship studies using dioxin congeners demonstrated a correlation between the relative AHR binding affinity and the magnitude of decrease in the number of HSPCs and CD34 expression, suggesting that AHR mediates the observed TCDD-elicited changes in HSPCs. Moreover, a significant reduction in lineage committed B cell-derived from HSCs was observed in the presence of TCDD, indicating impairment of human B cell development. Similar effects of TCDD were observed regardless of the use of stromal cells in cultures indicating a direct effect of TCDD on HSCs. Collectively, we demonstrate that AHR activation by TCDD on human HSCs impairs early stages of human B lymphopoiesis.

Rhizomucor and Scedosporium Infection Post Hematopoietic Stem-Cell Transplant

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Dânia Sofia Marques

2011-01-01

Full Text Available Hematopoietic stem-cell transplant recipients are at increased risk of developing invasive fungal infections. This is a major cause of morbidity and mortality. We report a case of a 17-year-old male patient diagnosed with severe idiopathic acquired aplastic anemia who developed fungal pneumonitis due to Rhizomucor sp. and rhinoencephalitis due to Scedosporium apiospermum 6 and 8 months after undergoing allogeneic hematopoietic stem-cell transplant from an HLA-matched unrelated donor. Discussion highlights risk factors for invasive fungal infections (i.e., mucormycosis and scedosporiosis, its clinical features, and the factors that must be taken into account to successfully treat them (early diagnosis, correction of predisposing factors, aggressive surgical debridement, and antifungal and adjunctive therapies.

Functional sex differences in human primary auditory cortex

NARCIS (Netherlands)

Ruytjens, Liesbet; Georgiadis, Janniko R.; Holstege, Gert; Wit, Hero P.; Albers, Frans W. J.; Willemsen, Antoon T. M.

2007-01-01

Background We used PET to study cortical activation during auditory stimulation and found sex differences in the human primary auditory cortex (PAC). Regional cerebral blood flow (rCBF) was measured in 10 male and 10 female volunteers while listening to sounds (music or white noise) and during a

Comparison of chemotherapy and hematopoietic stem cell ...

African Journals Online (AJOL)

2013-02-19

Feb 19, 2013 ... scores before and after hematopoietic stem cell transplantation (HSCT) and chemotherapy. Materials and Methods: Thirty-six patients undergoing HSCT were included in the study. A pre-HSCT dental treatment protocol was implemented that consisted of restoration of all active carious lesions, treatment of ...

Hematopoietic stem cell aging and self-renewal

NARCIS (Netherlands)

Dykstra, Brad; de Haan, Gerald

A functional decline of the immune system occurs during organismal aging that is attributable, in large part, to changes in the hematopoietic stem cell (HSC) compartment. In the mouse, several hallmark age-dependent changes in the HSC compartment have been identified, including an increase in HSC

Enrichment of human hematopoietic stem/progenitor cells facilitates transduction for stem cell gene therapy.

Science.gov (United States)

Baldwin, Kismet; Urbinati, Fabrizia; Romero, Zulema; Campo-Fernandez, Beatriz; Kaufman, Michael L; Cooper, Aaron R; Masiuk, Katelyn; Hollis, Roger P; Kohn, Donald B

2015-05-01

Autologous hematopoietic stem cell (HSC) gene therapy for sickle cell disease has the potential to treat this illness without the major immunological complications associated with allogeneic transplantation. However, transduction efficiency by β-globin lentiviral vectors using CD34-enriched cell populations is suboptimal and large vector production batches may be needed for clinical trials. Transducing a cell population more enriched for HSC could greatly reduce vector needs and, potentially, increase transduction efficiency. CD34(+) /CD38(-) cells, comprising ∼1%-3% of all CD34(+) cells, were isolated from healthy cord blood CD34(+) cells by fluorescence-activated cell sorting and transduced with a lentiviral vector expressing an antisickling form of beta-globin (CCL-β(AS3) -FB). Isolated CD34(+) /CD38(-) cells were able to generate progeny over an extended period of long-term culture (LTC) compared to the CD34(+) cells and required up to 40-fold less vector for transduction compared to bulk CD34(+) preparations containing an equivalent number of CD34(+) /CD38(-) cells. Transduction of isolated CD34(+) /CD38(-) cells was comparable to CD34(+) cells measured by quantitative PCR at day 14 with reduced vector needs, and average vector copy/cell remained higher over time for LTC initiated from CD34(+) /38(-) cells. Following in vitro erythroid differentiation, HBBAS3 mRNA expression was similar in cultures derived from CD34(+) /CD38(-) cells or unfractionated CD34(+) cells. In vivo studies showed equivalent engraftment of transduced CD34(+) /CD38(-) cells when transplanted in competition with 100-fold more CD34(+) /CD38(+) cells. This work provides initial evidence for the beneficial effects from isolating human CD34(+) /CD38(-) cells to use significantly less vector and potentially improve transduction for HSC gene therapy. © 2015 AlphaMed Press.

HDAd5/35++ Adenovirus Vector Expressing Anti-CRISPR Peptides Decreases CRISPR/Cas9 Toxicity in Human Hematopoietic Stem Cells

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Chang Li

2018-06-01

Full Text Available We generated helper-dependent HDAd5/35++ adenovirus vectors expressing CRISPR/Cas9 for potential hematopoietic stem cells (HSCs gene therapy of β-thalassemia and sickle cell disease through re-activation of fetal γ-globin expression (HDAd-globin-CRISPR. The process of CRISPR/Cas9 gene transfer using these vectors was not associated with death of human CD34+ cells and did not affect their in vitro expansion and erythroid differentiation. However, functional assays for primitive HSCs, e.g., multi-lineage progenitor colony formation and engraftment in irradiated NOD/Shi-scid/interleukin-2 receptor γ (IL-2Rγ null (NSG mice, revealed toxicity of HDAd-globin-CRISPR vectors related to the prolonged expression and activity of CRISPR/Cas9. To control the duration of CRISPR/Cas9 activity, we generated an HDAd5/35++ vector that expressed two anti-CRISPR (Acr peptides (AcrII4 and AcrII2 capable of binding to the CRISPR/Cas9 complex (HDAd-Acr. CD34+ cells that were sequentially infected with HDAd-CRISPR and HDAd-Acr engrafted at a significantly higher rate. Target site disruption frequencies in engrafted human cells were similar to those in pre-transplantation CD34+ cells, indicating that genome-edited primitive HSCs survived. In vitro differentiated HSCs isolated from transplanted mice demonstrated increased γ-globin expression as a result of genome editing. Our data indicate that the HDAd-Acr vector can be used as a tool to reduce HSC cytotoxicity of the CRISPR/Cas9 complex.

Telomerase-mediated life-span extension of human primary fibroblasts by human artificial chromosome (HAC) vector

International Nuclear Information System (INIS)

Shitara, Shingo; Kakeda, Minoru; Nagata, Keiko; Hiratsuka, Masaharu; Sano, Akiko; Osawa, Kanako; Okazaki, Akiyo; Katoh, Motonobu; Kazuki, Yasuhiro; Oshimura, Mitsuo; Tomizuka, Kazuma

2008-01-01

Telomerase-mediated life-span extension enables the expansion of normal cells without malignant transformation, and thus has been thought to be useful in cell therapies. Currently, integrating vectors including the retrovirus are used for human telomerase reverse transcriptase (hTERT)-mediated expansion of normal cells; however, the use of these vectors potentially causes unexpected insertional mutagenesis and/or activation of oncogenes. Here, we established normal human fibroblast (hPF) clones retaining non-integrating human artificial chromosome (HAC) vectors harboring the hTERT expression cassette. In hTERT-HAC/hPF clones, we observed the telomerase activity and the suppression of senescent-associated SA-β-galactosidase activity. Furthermore, the hTERT-HAC/hPF clones continued growing beyond 120 days after cloning, whereas the hPF clones retaining the silent hTERT-HAC senesced within 70 days. Thus, hTERT-HAC-mediated episomal expression of hTERT allows the extension of the life-span of human primary cells, implying that gene delivery by non-integrating HAC vectors can be used to control cellular proliferative capacity of primary cultured cells

Hhex Regulates Hematopoietic Stem Cell Self-Renewal and Stress Hematopoiesis via Repression of Cdkn2a.

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Jackson, Jacob T; Shields, Benjamin J; Shi, Wei; Di Rago, Ladina; Metcalf, Donald; Nicola, Nicos A; McCormack, Matthew P

2017-08-01

The hematopoietically expressed homeobox transcription factor (Hhex) is important for the maturation of definitive hematopoietic progenitors and B-cells during development. We have recently shown that in adult hematopoiesis, Hhex is dispensable for maintenance of hematopoietic stem cells (HSCs) and myeloid lineages but essential for the commitment of common lymphoid progenitors (CLPs) to lymphoid lineages. Here, we show that during serial bone marrow transplantation, Hhex-deleted HSCs are progressively lost, revealing an intrinsic defect in HSC self-renewal. Moreover, Hhex-deleted mice show markedly impaired hematopoietic recovery following myeloablation, due to a failure of progenitor expansion. In vitro, Hhex-null blast colonies were incapable of replating, implying a specific requirement for Hhex in immature progenitors. Transcriptome analysis of Hhex-null Lin - Sca + Kit + cells showed that Hhex deletion leads to derepression of polycomb repressive complex 2 (PRC2) and PRC1 target genes, including the Cdkn2a locus encoding the tumor suppressors p16 Ink 4 a and p19 Arf . Indeed, loss of Cdkn2a restored the capacity of Hhex-null blast colonies to generate myeloid progenitors in vitro, as well as hematopoietic reconstitution following myeloablation in vivo. Thus, HSCs require Hhex to promote PRC2-mediated Cdkn2a repression to enable continued self-renewal and response to hematopoietic stress. Stem Cells 2017;35:1948-1957. © 2017 AlphaMed Press.

Cytokine-free directed differentiation of human pluripotent stem cells efficiently produces hemogenic endothelium with lymphoid potential.

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Galat, Yekaterina; Dambaeva, Svetlana; Elcheva, Irina; Khanolkar, Aaruni; Beaman, Kenneth; Iannaccone, Philip M; Galat, Vasiliy

2017-03-17

The robust generation of human hematopoietic progenitor cells from induced or embryonic pluripotent stem cells would be beneficial for multiple areas of research, including mechanistic studies of hematopoiesis, the development of cellular therapies for autoimmune diseases, induced transplant tolerance, anticancer immunotherapies, disease modeling, and drug/toxicity screening. Over the past years, significant progress has been made in identifying effective protocols for hematopoietic differentiation from pluripotent stem cells and understanding stages of mesodermal, endothelial, and hematopoietic specification. Thus, it has been shown that variations in cytokine and inhibitory molecule treatments in the first few days of hematopoietic differentiation define primitive versus definitive potential of produced hematopoietic progenitor cells. The majority of current feeder-free, defined systems for hematopoietic induction from pluripotent stem cells include prolonged incubations with various cytokines that make the differentiation process complex and time consuming. We established that the application of Wnt agonist CHIR99021 efficiently promotes differentiation of human pluripotent stem cells in the absence of any hematopoietic cytokines to the stage of hemogenic endothelium capable of definitive hematopoiesis. The hemogenic endothelium differentiation was accomplished in an adherent, serum-free culture system by applying CHIR99021. Hemogenic endothelium progenitor cells were isolated on day 5 of differentiation and evaluated for their endothelial, myeloid, and lymphoid potential. Monolayer induction based on GSK3 inhibition, described here, yielded a large number of CD31 + CD34 + hemogenic endothelium cells. When isolated and propagated in adherent conditions, these progenitors gave rise to mature endothelium. When further cocultured with OP9 mouse stromal cells, these progenitors gave rise to various cells of myeloid lineages as well as natural killer lymphoid, T

Quantitative and qualitative assessment of reactive hematopoietic bone marrow in aplastic anemia using MR spectroscopy with variable echo times

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Amano, Yasuo; Kumazaki, Tatsuo [Department of Radiology, Nippon Medical School, Tokyo (Japan)

2002-01-01

Objective: To assess quantitative and qualitative differences in water components between normal bone marrow and reactive hematopoietic marrow in aplastic anemia using magnetic resonance (MR) spectroscopy with variable echo times (TEs). Design: Water content, T2 value of the water component, and signal change in water related to TE were assessed in normal bone marrow and reactive hematopoietic bone marrow by a stimulated echo acquisition mode with TEs of 30, 45, 60, and 90 ms. Patients: Six patients with aplastic anemia (13-84 years) and seven normal volunteers (25-38 years) were examined. Results and conclusion: Reactive hematopoietic marrow showed significantly higher water content than normal bone marrow. The T2 value of water components tended to be longer in reactive hematopoietic marrow. Water signal ratio related to TE was significantly higher in reactive hematopoietic marrow. These results suggest a quantitative and qualitative difference in water components between normal and reactive hematopoietic bone marrow. (orig.)

JAK2V617F expression in mice amplifies early hematopoietic cells and gives them a competitive advantage that is hampered by IFNα.

Science.gov (United States)

Hasan, Salma; Lacout, Catherine; Marty, Caroline; Cuingnet, Marie; Solary, Eric; Vainchenker, William; Villeval, Jean-Luc

2013-08-22

The acquired gain-of-function V617F mutation in the Janus Kinase 2 (JAK2(V617F)) is the main mutation involved in BCR/ABL-negative myeloproliferative neoplasms (MPNs), but its effect on hematopoietic stem cells as a driver of disease emergence has been questioned. Therefore, we reinvestigated the role of endogenous expression of JAK2(V617F) on early steps of hematopoiesis as well as the effect of interferon-α (IFNα), which may target the JAK2(V617F) clone in humans by using knock-in mice with conditional expression of JAK2(V617F) in hematopoietic cells. These mice develop a MPN mimicking polycythemia vera with large amplification of myeloid mature and precursor cells, displaying erythroid endogenous growth and progressing to myelofibrosis. Interestingly, early hematopoietic compartments [Lin-, LSK, and SLAM (LSK/CD48-/CD150+)] increased with the age. Competitive repopulation assays demonstrated disease appearance and progressive overgrowth of myeloid, Lin-, LSK, and SLAM cells, but not lymphocytes, from a low number of engrafted JAK2(V617F) SLAM cells. Finally, IFNα treatment prevented disease development by specifically inhibiting JAK2(V617F) cells at an early stage of differentiation and eradicating disease-initiating cells. This study shows that JAK2(V617F) in mice amplifies not only late but also early hematopoietic cells, giving them a proliferative advantage through high cell cycling and low apoptosis that may sustain MPN emergence but is lost upon IFNα treatment.

Engineering HIV-1-resistant T-cells from short-hairpin RNA-expressing hematopoietic stem/progenitor cells in humanized BLT mice.

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Gene-Errol E Ringpis

Full Text Available Down-regulation of the HIV-1 coreceptor CCR5 holds significant potential for long-term protection against HIV-1 in patients. Using the humanized bone marrow/liver/thymus (hu-BLT mouse model which allows investigation of human hematopoietic stem/progenitor cell (HSPC transplant and immune system reconstitution as well as HIV-1 infection, we previously demonstrated stable inhibition of CCR5 expression in systemic lymphoid tissues via transplantation of HSPCs genetically modified by lentiviral vector transduction to express short hairpin RNA (shRNA. However, CCR5 down-regulation will not be effective against existing CXCR4-tropic HIV-1 and emergence of resistant viral strains. As such, combination approaches targeting additional steps in the virus lifecycle are required. We screened a panel of previously published shRNAs targeting highly conserved regions and identified a potent shRNA targeting the R-region of the HIV-1 long terminal repeat (LTR. Here, we report that human CD4(+ T-cells derived from transplanted HSPC engineered to co-express shRNAs targeting CCR5 and HIV-1 LTR are resistant to CCR5- and CXCR4- tropic HIV-1-mediated depletion in vivo. Transduction with the combination vector suppressed CXCR4- and CCR5- tropic viral replication in cell lines and peripheral blood mononuclear cells in vitro. No obvious cytotoxicity or interferon response was observed. Transplantation of combination vector-transduced HSPC into hu-BLT mice resulted in efficient engraftment and subsequent stable gene marking and CCR5 down-regulation in human CD4(+ T-cells within peripheral blood and systemic lymphoid tissues, including gut-associated lymphoid tissue, a major site of robust viral replication, for over twelve weeks. CXCR4- and CCR5- tropic HIV-1 infection was effectively inhibited in hu-BLT mouse spleen-derived human CD4(+ T-cells ex vivo. Furthermore, levels of gene-marked CD4(+ T-cells in peripheral blood increased despite systemic infection with either

Exposure Setup and Dosimetry for a Study on Effects of Mobile Communication Signals on Human Hematopoietic Stem Cells in vitro

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M. Rohland

2017-09-01

Full Text Available In this paper we describe the design of an exposure setup used to study possible non-thermal effects due to the exposure of human hematopoietic stem cells to GSM, UMTS and LTE mobile communication signals. The experiments are performed under fully blinded conditions in a TEM waveguide located inside an incubator to achieve defined environmental conditions as required for the living cells. Chamber slides containing the cells in culture medium are placed on the septum of the waveguide. The environmental and exposure parameters such as signal power, temperatures, relative humidity and CO2 content of the surrounding atmosphere are monitored permanently during the exposure experiment. The power of the exposure signals required to achieve specific absorption rates of 0.5, 1, 2 and 4 W kg−1 are determined by numerical calculation of the field distribution inside the cell culture medium at 900 MHz (GSM, 1950 MHz (UMTS and 2535 MHz (LTE. The dosimetry is verified both with scattering parameter measurements on the waveguide with and without containers filled with cell culture medium and with temperature measurements with non-metallic probes in separate heating experiments.

Age-related mutations associated with clonal hematopoietic expansion and malignancies.

Science.gov (United States)

Xie, Mingchao; Lu, Charles; Wang, Jiayin; McLellan, Michael D; Johnson, Kimberly J; Wendl, Michael C; McMichael, Joshua F; Schmidt, Heather K; Yellapantula, Venkata; Miller, Christopher A; Ozenberger, Bradley A; Welch, John S; Link, Daniel C; Walter, Matthew J; Mardis, Elaine R; Dipersio, John F; Chen, Feng; Wilson, Richard K; Ley, Timothy J; Ding, Li

2014-12-01

Several genetic alterations characteristic of leukemia and lymphoma have been detected in the blood of individuals without apparent hematological malignancies. The Cancer Genome Atlas (TCGA) provides a unique resource for comprehensive discovery of mutations and genes in blood that may contribute to the clonal expansion of hematopoietic stem/progenitor cells. Here, we analyzed blood-derived sequence data from 2,728 individuals from TCGA and discovered 77 blood-specific mutations in cancer-associated genes, the majority being associated with advanced age. Remarkably, 83% of these mutations were from 19 leukemia and/or lymphoma-associated genes, and nine were recurrently mutated (DNMT3A, TET2, JAK2, ASXL1, TP53, GNAS, PPM1D, BCORL1 and SF3B1). We identified 14 additional mutations in a very small fraction of blood cells, possibly representing the earliest stages of clonal expansion in hematopoietic stem cells. Comparison of these findings to mutations in hematological malignancies identified several recurrently mutated genes that may be disease initiators. Our analyses show that the blood cells of more than 2% of individuals (5-6% of people older than 70 years) contain mutations that may represent premalignant events that cause clonal hematopoietic expansion.

Drug discovery for Diamond-Blackfan anemia using reprogrammed hematopoietic progenitors

Science.gov (United States)

Doulatov, Sergei; Vo, Linda T.; Macari, Elizabeth R.; Wahlster, Lara; Kinney, Melissa A.; Taylor, Alison M.; Barragan, Jessica; Gupta, Manav; McGrath, Katherine; Lee, Hsiang-Ying; Humphries, Jessica M.; DeVine, Alex; Narla, Anupama; Alter, Blanche P.; Beggs, Alan H.; Agarwal, Suneet; Ebert, Benjamin L.; Gazda, Hanna T.; Lodish, Harvey F.; Sieff, Colin A.; Schlaeger, Thorsten M.; Zon, Leonard I.; Daley, George Q.

2017-01-01

Diamond-Blackfan anemia (DBA) is a congenital disorder characterized by the failure of erythroid progenitor differentiation, severely curtailing red blood cell production. Because many DBA patients fail to respond to corticosteroid therapy, there is considerable need for therapeutics for this disorder. Identifying therapeutics for DBA requires circumventing the paucity of primary patient blood stem and progenitor cells. To this end, we adopted a reprogramming strategy to generate expandable hematopoietic progenitor cells from induced pluripotent stem cells (iPSCs) from DBA patients. Reprogrammed DBA progenitors recapitulate defects in erythroid differentiation, which were rescued by gene complementation. Unbiased chemical screens identified SMER28, a small-molecule inducer of autophagy, which enhanced erythropoiesis in a range of in vitro and in vivo models of DBA. SMER28 acted through autophagy factor ATG5 to stimulate erythropoiesis and up-regulate expression of globin genes. These findings present an unbiased drug screen for hematological disease using iPSCs and identify autophagy as a therapeutic pathway in DBA. PMID:28179501

Immunoglobulin therapy in hematologic neoplasms and after hematopoietic cell transplantation.

Science.gov (United States)

Ueda, Masumi; Berger, Melvin; Gale, Robert Peter; Lazarus, Hillard M

2018-03-01

Immunoglobulins are used to prevent or reduce infection risk in primary immune deficiencies and in settings which exploit its anti-inflammatory and immune-modulatory effects. Rigorous proof of immunoglobulin efficacy in persons with lympho-proliferative neoplasms, plasma cell myeloma, and persons receiving hematopoietic cell transplants is lacking despite many clinical trials. Further, there are few consensus guidelines or algorithms for use in these conditions. Rapid development of new therapies targeting B-cell signaling and survival pathways and increased use of chimeric antigen receptor T-cell (CAR-T) therapy will likely result in more acquired deficiencies of humoral immunity and infections in persons with cancer. We review immunoglobulin formulations and discuss efficacy and potential adverse effects in the context of preventing infections and in graft-versus-host disease. We suggest an algorithm for evaluating acquired deficiencies of humoral immunity in persons with hematologic neoplasms and recommend appropriate use of immunoglobulin therapy. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Brief Report: Human Acute Myeloid Leukemia Reprogramming to Pluripotency Is a Rare Event and Selects for Patient Hematopoietic Cells Devoid of Leukemic Mutations.

Science.gov (United States)

Lee, Jong-Hee; Salci, Kyle R; Reid, Jennifer C; Orlando, Luca; Tanasijevic, Borko; Shapovalova, Zoya; Bhatia, Mickie

2017-09-01

Induced pluripotent stem cell reprogramming has provided critical insights into disease processes by modeling the genetics and related clinical pathophysiology. Human cancer represents highly diverse genetics, as well as inter- and intra-patient heterogeneity, where cellular model systems capable of capturing this disease complexity would be invaluable. Acute myeloid leukemia (AML) represents one of most heterogeneous cancers and has been divided into genetic subtypes correlated with unique risk stratification over the decades. Here, we report our efforts to induce pluripotency from the heterogeneous population of human patients that represents this disease in the clinic. Using robust optimized reprogramming methods, we demonstrate that reprogramming of AML cells harboring leukemic genomic aberrations is a rare event with the exception of those with de novo mixed-lineage leukemia (MLL) mutations that can be reprogrammed and model drug responses in vitro. Our findings indicate that unlike hematopoietic cells devoid of genomic aberrations, AML cells harboring driver mutations are refractory to reprogramming. Expression of MLL fusion proteins in AML cells did not contribute to induced reprogramming success, which continued to select for patient derived cells devoid of AML patient-specific aberrations. Our study reveals that unanticipated blockades to achieving pluripotency reside within the majority of transformed AML patient cells. Stem Cells 2017;35:2095-2102. © 2017 AlphaMed Press.

Evolution of human cytomegalovirus-seronegative donor/-seropositive recipient high-risk combination frequency in allogeneic hematopoietic stem cell transplantations at Institute of Hematology and Blood Transfusion during 1995-2014.

Science.gov (United States)

Nemeckova, S; Sroller, V; Stastna-Markova, M

2016-04-01

Human cytomegalovirus (HCMV) establishes lifelong latent infection that can result in severe life-threatening disease in immunosuppressed patients after hematopoietic stem cell transplantation (HSCT). An HCMV-seropositive transplant recipient who receives a graft from a seronegative donor (R+/D-) is at high risk of recurrent HCMV reactivation. To assess the incidence of R+/D- combination, we retrospectively evaluated HCMV-seronegative donors for 746 allogeneic HSCT treatments carried out at our center during 1995-2014. In our cohort, 20% HCMV-seronegative HSCT recipients, 21% HCMV-seronegative related graft donors, and 52% HCMV-seronegative unrelated graft donors were included. Analyses of the HCMV serostatus of hematopoietic stem cell donors during 2 consecutive calendar periods (1995-2005 and 2006-2014) showed a significant increase in the proportion of seronegative donors (odds ratio [OR] = 1.947). In addition, the number of HSCT treatments using an unrelated donor increased (OR = 2.376). Finally, the use of grafts from countries with a very low HCMV prevalence increased. This increase in HCMV seronegativity in unrelated donors and the increased proportion of unrelated donors were responsible for the increased occurrence of the high-risk combination R+/D- (OR = 1.680). If the reduction in the rate of HCMV-seropositive graft donors continues, an increased frequency of HCMV reactivation events in our transplant recipients can be expected, because of the increasing occurrence of the high-risk R+/D- combination. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Anxiety, fatigue, and attentional bias toward threat in patients with hematopoietic tumors.

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Kohei Koizumi

Full Text Available Cancer patients with hematopoietic tumors exhibit particularly high rates of anxiety disorders and depression, and often develop negative affect. In addition, psychological problems experienced by cancer patients impair their quality of life. When cancer patients feel anxious, they tend to direct their attention toward stimuli associated with threat in the surrounding environment. If attentional bias occurs in patients with hematopoietic tumors, who are at particular risk of developing negative affect, resolution of the bias could be useful in alleviating their anxiety. The current study examined the association between attentional bias and negative affect in patients with hematopoietic tumors and tested the hypothesis that negative affect would be more severe in those who exhibited greater attentional bias. Twenty-seven patients with hematopoietic tumors participated in the study. Reaction time (RT was measured as the time between the presentation of the threatening and neutral images, and the subject's button press to indicate choice (neutral expressions. Eight combinations of "threatening" expressions with high emotional valence and "neutral" expressions with low emotional valence were presented. The images used to measure attentional bias were taken from the Japanese Female Facial Expression Database and had been rated as expressive of anger, sadness, or neutrality, with predetermined emotional valence. Psychological testing was performed with the Profile of Mood States (POMS. To examine the association between attentional bias and negative affect, we calculated Spearman's rank correlation coefficients for RTs and POMS. Subjects' mean RT was 882.9 (SD = 100.9 ms, and 19 of the 27 subjects exhibited slower RTs relative to healthy individuals. RT was significantly positively correlated with Tension-Anxiety (r = .679, p < .01 and Fatigue (r = .585, p < .01 subscale scores. The results of the study suggested that attentional bias toward

HANPP Collection: Global Patterns in Human Appropriation of Net Primary Productivity (HANPP)

Data.gov (United States)

National Aeronautics and Space Administration — The Global Patterns in Human Appropriation of Net Primary Productivity (HANPP) portion of the HANPP Collection represents a digital map of human appropriation of net...

Transfection of Primary Human Skin Fibroblasts for Peroxisomal Studies

NARCIS (Netherlands)

Koster, Janet; Waterham, Hans R.

2017-01-01

Functional studies with primary human skin fibroblasts from patients with a peroxisomal disorder often require efficient transfection with plasmids to correct the genetic defect or to express heterologous reporter proteins. Here, we describe a protocol we commonly use for efficient nonviral

The Impact of Growth Hormone Therapy on the Apoptosis Assessment in CD34+ Hematopoietic Cells from Children with Growth Hormone Deficiency

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Miłosz Piotr Kawa

2017-01-01

Full Text Available Growth hormone (GH modulates hematopoietic cell homeostasis and is associated with apoptosis control, but with limited mechanistic insights. Aim of the study was to determine whether GH therapeutic supplementation (GH-TS could affect apoptosis of CD34+ cells enriched in hematopoietic progenitor cells of GH deficient (GHD children. CD34+ cells from peripheral blood of 40 GHD children were collected before and in 3rd and 6th month of GH-TS and compared to 60 controls adjusted for bone age, sex, and pubertal development. Next, apoptosis assessment via different molecular techniques was performed. Finally, to comprehensively characterize apoptosis process, global gene expression profile was determined using genome-wide RNA microarray technology. Results showed that GH-TS significantly reduced spontaneous apoptosis in CD34+ cells (p < 0.01 and results obtained using different methods to detect early and late apoptosis in analyzed cells population were consistent. GH-TS was also associated with significant downregulation of several members of TNF-alpha superfamily and other genes associated with apoptosis and stress response. Moreover, the significant overexpression of cyto-protective and cell cycle-associated genes was detected. These findings suggest that recombinant human GH has a direct anti-apoptotic activity in hematopoietic CD34+ cells derived from GHD subjects in course of GH-TS.

Bottlenecks in deriving definitive hematopoietic stem cells from human pluripotent stem cells: a CIRM mini-symposium and workshop report.

Science.gov (United States)

Shepard, Kelly A; Talib, Sohel

2014-07-01

On August 29, 2013, the California Institute for Regenerative Medicine (CIRM) convened a small group of investigators in San Francisco, CA, to discuss a longstanding challenge in the stem cell field: the inability to derive fully functional, definitive hematopoietic stem cells (HSCs) from pluripotent stem cells (PSCs). To date, PSC-derived HSCs have been deficient in their developmental potential and their ability to self-renew and engraft upon transplantation. Tasked with identifying key challenges to overcoming this "HSC bottleneck", workshop participants identified critical knowledge gaps in two key areas: (a) understanding the ontogeny of human HSCs, and (b) understanding of the intrinsic and extrinsic factors that govern HSC behavior and function. They agreed that development of new methods and tools is critical for addressing these knowledge gaps. These include molecular profiling of key HSC properties, development of new model systems/assays for predicting and assessing HSC function, and novel technological advancements for manipulating cell culture conditions and genetic programs. The workshop produced tangible advances, including providing a current definition of the nature and challenge of the HSC bottleneck and identifying key mechanistic studies of HSC biology that should be prioritized for future funding initiatives (e.g., including higher risk approaches that have potential for high gain). ©AlphaMed Press.

Pilot experience with opebacan/rBPI21 in myeloablative hematopoietic cell transplantation [version 1; referees: 2 approved

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Eva Guinan

2015-12-01

Full Text Available Bacterial infection and inflammation contribute significantly to the morbidity and mortality of myeloablative allogeneic hematopoietic cell transplantation (HCT. Endotoxin, a component of the outer membrane of Gram-negative bacteria, is a potent inflammatory stimulus in humans. Bactericidal/permeability increasing protein (BPI, a constituent of human neutrophil granules, binds endotoxin thereby precluding endotoxin-induced inflammation and also has direct anti-infective properties against bacteria. As a consequence of myeloablative therapy used in preparation for hematopoietic cell infusion, patients experience gastrointestinal leak of bacteria and bacterial toxins into the systemic circulation and a period of inflammatory cytokine elevation associated with subsequent regimen-related toxicities.  Patients frequently become endotoxemic and febrile as well as BPI-deficient due to sustained neutropenia. To examine whether enhancing endotoxin-neutralizing and anti-infective activity by exogenous administration of a recombinant N-terminal fragment of BPI (rBPI21, generic name opebacan might ameliorate regimen-related toxicities including infection, we recruited patients scheduled to undergo myeloablative HCT to participate in a proof-of-concept prospective phase I/II trial. After the HCT preparative regimen was completed, opebacan was initiated 18-36 hours prior to administration of allogeneic hematopoietic stem cells (defined as Day 0 and continued for 72 hours. The trial was to have included escalation of rBPI21 dose and duration but was stopped prematurely due to lack of further drug availability.  Therefore, to better understand the clinical course of opebacan-treated patients (n=6, we compared their outcomes with a comparable cohort meeting the same eligibility criteria and enrolled in a non-interventional myeloablative HCT observational study (n = 35.  Opebacan-treated participants had earlier platelet engraftment (p=0.005, mirroring

Comparison of Different Cytokine Conditions Reveals Resveratrol as a New Molecule for Ex Vivo Cultivation of Cord Blood-Derived Hematopoietic Stem Cells.

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Heinz, Niels; Ehrnström, Birgitta; Schambach, Axel; Schwarzer, Adrian; Modlich, Ute; Schiedlmeier, Bernhard

2015-09-01

Human cord blood (CB)-derived hematopoietic stem cells (HSCs) are an interesting source for HSC transplantation. However, the number of collected CB-HSCs is often too low for one transplantation; therefore, ex vivo expansion of CB-HSCs is desirable. Current expansion protocols are based on the use of cytokine combinations, including insulin-like growth factor-binding protein 2 (IGFBP2) and angiopoietin-like proteins, or combinations with "small molecules" such as stemregenin-1. The aim of our project was to compare the potential of different CB-HSC expansion strategies side-by-side by phenotypical analysis in vitro and serial engraftment properties in NOD/SCID/IL2rg-/- (NSG) immunodeficient mice. We further identified resveratrol, a naturally occurring polyphenol, as a new, alternative small molecule combined with cytokines to facilitate serum-free ex vivo expansion of human CB-HSCs. The cultivation in resveratrol preserved the CB-HSC phenotype in vitro most efficiently and was ∼2 times more potent than commonly used cytokine conditions (including stem cell factor, thrombopoietin, Fms-related tyrosine kinase 3 ligand, interleukin-6) and the recently established serum-free culture, including IGFBP2 and angiopoietin-like 5. Serial transplantation studies further confirmed resveratrol to support robust multilineage engraftment in primary and secondary NSG recipients. Therefore, our work proposes resveratrol as a new small molecule for improved ex vivo culture and modification of human HSCs based on an efficient ex vivo propagation of the HSC fate. Human cord blood (CB)-derived hematopoietic stem cells (HSCs) are an important source for HSC transplantations but restricted in their usage because of their low numbers. In gene therapy, modifications of HSCs relies on their ex vivo modification without losing their stemness properties. Therefore, ex vivo cultivation and expansion of CB-HSCs is important for their effective application in HSC transplantation and gene

Aging of hematopoietic stem cells: DNA damage and mutations?

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Moehrle, Bettina M; Geiger, Hartmut

2016-10-01

Aging in the hematopoietic system and the stem cell niche contributes to aging-associated phenotypes of hematopoietic stem cells (HSCs), including leukemia and aging-associated immune remodeling. Among others, the DNA damage theory of aging of HSCs is well established, based on the detection of a significantly larger amount of γH2AX foci and a higher tail moment in the comet assay, both initially thought to be associated with DNA damage in aged HSCs compared with young cells, and bone marrow failure in animals devoid of DNA repair factors. Novel data on the increase in and nature of DNA mutations in the hematopoietic system with age, the quality of the DNA damage response in aged HSCs, and the nature of γH2AX foci question a direct link between DNA damage and the DNA damage response and aging of HSCs, and rather favor changes in epigenetics, splicing-factors or three-dimensional architecture of the cell as major cell intrinsic factors of HSCs aging. Aging of HSCs is also driven by a strong contribution of aging of the niche. This review discusses the DNA damage theory of HSC aging in the light of these novel mechanisms of aging of HSCs. Copyright © 2016 ISEH - International Society for Experimental Hematology. Published by Elsevier Inc. All rights reserved.

Placenta as a source of hematopoietic stem cells

NARCIS (Netherlands)

E.A. Dzierzak (Elaine); C. Robin (Catherine)

2010-01-01

textabstractThe placenta is a large, highly vascularised hematopoietic tissue that functions during the embryonic and foetal development of eutherian mammals. Although recognised as the interface tissue important in the exchange of oxygen, nutrients and waste products between the foetus and mother,

Preservation of differentiation and clonogenic potential of human hematopoietic stem and progenitor cells during lyophilization and ambient storage.

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Sandhya S Buchanan

2010-09-01

Full Text Available Progenitor cell therapies show great promise, but their potential for clinical applications requires improved storage and transportation. Desiccated cells stored at ambient temperature would provide economic and practical advantages over approaches employing cell freezing and subzero temperature storage. The objectives of this study were to assess a method for loading the stabilizing sugar, trehalose, into hematopoietic stem and progenitor cells (HPC and to evaluate the effects of subsequent freeze-drying and storage at ambient temperature on differentiation and clonogenic potential. HPC were isolated from human umbilical cord blood and loaded with trehalose using an endogenous cell surface receptor, termed P2Z. Solution containing trehalose-loaded HPC was placed into vials, which were transferred to a tray freeze-dryer and removed during each step of the freeze-drying process to assess differentiation and clonogenic potential. Control groups for these experiments were freshly isolated HPC. Control cells formed 1450+/-230 CFU-GM, 430+/-140 BFU-E, and 50+/-40 CFU-GEMM per 50 microL. Compared to the values for the control cells, there was no statistical difference observed for cells removed at the end of the freezing step or at the end of primary drying. There was a gradual decrease in the number of CFU-GM and BFU-E for cells removed at different temperatures during secondary drying; however, there were no significant differences in the number of CFU-GEMM. To determine storage stability of lyophilized HPC, cells were stored for 4 weeks at 25 degrees C in the dark. Cells reconstituted immediately after lyophilization produced 580+/-90 CFU-GM ( approximately 40%, relative to unprocessed controls p<0.0001, 170+/-70 BFU-E (approximately 40%, p<0.0001, and 41+/-22 CFU-GEMM (approximately 82%, p = 0.4171, and cells reconstituted after 28 days at room temperature produced 513+/-170 CFU-GM (approximately 35%, relative to unprocessed controls, p<0

Loss of Folliculin Disrupts Hematopoietic Stem Cell Quiescence and Homeostasis Resulting in Bone Marrow Failure.

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Baba, Masaya; Toyama, Hirofumi; Sun, Lei; Takubo, Keiyo; Suh, Hyung-Chan; Hasumi, Hisashi; Nakamura-Ishizu, Ayako; Hasumi, Yukiko; Klarmann, Kimberly D; Nakagata, Naomi; Schmidt, Laura S; Linehan, W Marston; Suda, Toshio; Keller, Jonathan R

2016-04-01

Folliculin (FLCN) is an autosomal dominant tumor suppressor gene that modulates diverse signaling pathways required for growth, proliferation, metabolism, survival, motility, and adhesion. FLCN is an essential protein required for murine embryonic development, embryonic stem cell (ESC) commitment, and Drosophila germline stem cell maintenance, suggesting that Flcn may be required for adult stem cell homeostasis. Conditional inactivation of Flcn in adult hematopoietic stem/progenitor cells (HSPCs) drives hematopoietic stem cells (HSC) into proliferative exhaustion resulting in the rapid depletion of HSPC, loss of all hematopoietic cell lineages, acute bone marrow (BM) failure, and mortality after 40 days. HSC that lack Flcn fail to reconstitute the hematopoietic compartment in recipient mice, demonstrating a cell-autonomous requirement for Flcn in HSC maintenance. BM cells showed increased phosphorylation of Akt and mTorc1, and extramedullary hematopoiesis was significantly reduced by treating mice with rapamycin in vivo, suggesting that the mTorc1 pathway was activated by loss of Flcn expression in hematopoietic cells in vivo. Tfe3 was activated and preferentially localized to the nucleus of Flcn knockout (KO) HSPCs. Tfe3 overexpression in HSPCs impaired long-term hematopoietic reconstitution in vivo, recapitulating the Flcn KO phenotype, and supporting the notion that abnormal activation of Tfe3 contributes to the Flcn KO phenotype. Flcn KO mice develop an acute histiocytic hyperplasia in multiple organs, suggesting a novel function for Flcn in macrophage development. Thus, Flcn is intrinsically required to maintain adult HSC quiescence and homeostasis, and Flcn loss leads to BM failure and mortality in mice. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

The Microtubule Plus-End Tracking Protein CLASP2 Is Required for Hematopoiesis and Hematopoietic Stem Cell Maintenance

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Ksenija Drabek

2012-10-01

Full Text Available Mammalian CLASPs are microtubule plus-end tracking proteins whose essential function as regulators of microtubule behavior has been studied mainly in cultured cells. We show here that absence of murine CLASP2 in vivo results in thrombocytopenia, progressive anemia, and pancytopenia, due to defects in megakaryopoiesis, in erythropoiesis, and in the maintenance of hematopoietic stem cell activity. Furthermore, microtubule stability and organization are affected upon attachment of Clasp2 knockout hematopoietic stem-cell-enriched populations, and these cells do not home efficiently toward their bone marrow niche. Strikingly, CLASP2-deficient hematopoietic stem cells contain severely reduced mRNA levels of c-Mpl, which encodes the thrombopoietin receptor, an essential factor for megakaryopoiesis and hematopoietic stem cell maintenance. Our data suggest that thrombopoietin signaling is impaired in Clasp2 knockout mice. We propose that the CLASP2-mediated stabilization of microtubules is required for proper attachment, homing, and maintenance of hematopoietic stem cells and that this is necessary to sustain c-Mpl transcription.

Characterization of primary cilia and Hedgehog signaling during development of the human pancreas and in human pancreatic duct cancer cell lines

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Nielsen, Sonja K; Møllgård, Kjeld; Clement, Christian A

2008-01-01

Hedgehog (Hh) signaling controls pancreatic development and homeostasis; aberrant Hh signaling is associated with several pancreatic diseases. Here we investigated the link between Hh signaling and primary cilia in the human developing pancreatic ducts and in cultures of human pancreatic duct...... adenocarcinoma cell lines, PANC-1 and CFPAC-1. We show that the onset of Hh signaling from human embryogenesis to fetal development is associated with accumulation of Hh signaling components Smo and Gli2 in duct primary cilia and a reduction of Gli3 in the duct epithelium. Smo, Ptc, and Gli2 localized to primary...... cilia of PANC-1 and CFPAC-1 cells, which may maintain high levels of nonstimulated Hh pathway activity. These findings indicate that primary cilia are involved in pancreatic development and postnatal tissue homeostasis....

Contrast enhancement and morphological findings of hematopoietic regions of bone marrow on MR imaging. Comparative study with spondylitis and vertebral tumors

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Amano, Yasuo; Hayashi, Hiromitsu; Matsuura, Maki; Watari, Jun; Kumazaki, Tatsuo [Nippon Medical School, Tokyo (Japan)

1995-06-01

The enhanced MR findings of hematopoietic regions in aplastic anemia were compared with those of spondylitis, metastatic vertebral tumors and hematologic neoplasms. The enhanced MR images showed hematopoietic regions to homogeneously enhance and occupy the margin of vertebral bodies, while spondylitis and metastatic tumors appeared as round, inhomogeneously enhancing lesions. MR images of leukemia and myelodysplastic syndrome showed homogeneous enhancement at the margins of vertebrae that was difficult to differentiate from hematopoietic regions. Enhanced MR images were useful in detecting the hematopoietic areas in marrow and differentiating them from spondylitis and metastatic tumors, although further experience is needed to distinguish between tumorous hyperplastic regions and benign hematopoietic regions in marrow. (author).

The human protooncogene product p33pim is expressed during fetal hematopoiesis and in diverse leukemias

International Nuclear Information System (INIS)

Amson, R.; Przedborski, S.; Telerman, A.; Sigaux, F.; Flandrin, G.; Givol, D.

1989-01-01

The authors measured the human pim-1 protooncogene (PIM) expression during fetal development and in hematopoietic malignancies. The data indicate that during human fetal hematopoiesis the 33-kDa pim product, p33pim, is highly expressed in the liver and the spleen. In contrast, a the adult stage it is only slightly expressed in circulating granulocytes. Out of 70 hematopoietic malignancies analyzed, 51 patients and 19 cell lines, p33pim was overexpressed in ∼ 30% of the samples, particularly in myeloid and lymphoid acute leukemias. This overexpression was unrelated to any stage of cellular differentiation and was not due to gene rearrangement or amplification. These results imply a physiological role of the pim-1 protooncogene during hematopoietic development and a deregulation in various leukemias

Accelerated postirradiation recovery of hematopoietic marrow following priming with low doses of vincristine

International Nuclear Information System (INIS)

Johnke, R.M.; Abernathy, R.S.

1990-01-01

The present investigation is a continuation of efforts to characterize the radioprotective potential of priming with vincristine (VcR). In this study, the postirradiation recovery kinetics of the marrow's hematopoietic stem cell, progenitor cell, and stromal cell compartments were monitored following exposure to a range of sublethal radiation doses to determine (a) the optimal VcR/radiation intertreatment interval for achieving maximal hematopoietic protection, (b) whether this optimal interval is influenced by the dose of radiation administered, and (c) whether the radioprotection observed involves the hematopoietic stroma. The results demonstrate that the degree of radioprotection observed was significantly influenced by the scheduling of the VcR priming dose with respect to the radiation exposure. An intertreatment interval of 24 h provided maximal radioprotective benefit irrespective of the radiation dose administered. Additionally, the radioprotection following VcR priming appeared to be more the result of an accelerated recovery in the hematopoietic stem cell and progenitor cell compartments than a change in their intrinsic radiosensitivity. The data also suggest that this accelerated recovery was not a consequence of greater radioprotection of marrow stroma. Finally, the radioprotection observed following VcR priming did not appear to involve a selective lineage response by either the erythroid or the granulomonocytic progenitor compartments

Posttransplant Intramuscular Injection of PLX-R18 Mesenchymal-Like Adherent Stromal Cells Improves Human Hematopoietic Engraftment in A Murine Transplant Model

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Leland Metheny

2018-02-01

Full Text Available Late-term complications of hematopoietic cell transplantation (HCT are numerous and include incomplete engraftment. One possible mechanism of incomplete engraftment after HCT is cytokine-mediated suppression or dysfunction of the bone marrow microenvironment. Mesenchymal stromal cells (MSCs elaborate cytokines that nurture or stimulate the marrow microenvironment by several mechanisms. We hypothesize that the administration of exogenous MSCs may modulate the bone marrow milieu and improve peripheral blood count recovery in the setting of incomplete engraftment. In the current study, we demonstrated that posttransplant intramuscular administration of human placental derived mesenchymal-like adherent stromal cells [PLacental eXpanded (PLX-R18] harvested from a three-dimensional in vitro culture system improved posttransplant engraftment of human immune compartment in an immune-deficient murine transplantation model. As measured by the percentage of CD45+ cell recovery, we observed improvement in the peripheral blood counts at weeks 6 (8.4 vs. 24.1%, p < 0.001 and 8 (7.3 vs. 13.1%, p < 0.05 and in the bone marrow at week 8 (28 vs. 40.0%, p < 0.01 in the PLX-R18 cohort. As measured by percentage of CD19+ cell recovery, there was improvement at weeks 6 (12.6 vs. 3.8% and 8 (10.1 vs. 4.1%. These results suggest that PLX-R18 may have a therapeutic role in improving incomplete engraftment after HCT.

Auto-mobilized adult hematopoietic stem cells advance neovasculature in diabetic retinopathy of mice

Institute of Scientific and Technical Information of China (English)

TIAN Bei; LI Xiao-xin; SHEN Li; ZHAO Min; YU Wen-zhen

2010-01-01

Background Hematopoietic stem cells (HSCs) can be used to deliver functionally active angiostatic molecules to the retinal vasculature by targeting active astrocytes and may be useful in targeting pre-angiogenic retinal lesions. We sought to determine whether HSC mobilization can ameliorate early diabetic retinopathy in mice.Methods Mice were devided into four groups: normal mice control group, normal mice HSC-mobilized group, diabetic mice control group and diabetic mice HSC mobilized group. Murine stem cell growth factor (murine SCF) and recombined human granulocyte colony stimulating factor (rhG-csf) were administered to the mice with diabetes and without diabetes for continuous 5 days to induce autologous HSCs mobilization, and subcutaneous injection of physiological saline was used as control. Immunohistochemical double staining was conducted with anti-mouse rat CD31 monoclonal antibody and anti-BrdU rat antibody.Results Marked HSCs clearly increased after SCF plus G-csf-mobilization. Non-mobilized diabetic mice showed more HSCs than normal mice (P=0.032), and peripheral blood significantly increased in both diabetic and normal mice (P=0.000).Diabetic mice showed more CD31 positive capillary vessels (P=0.000) and accelerated endothelial cell regeneration. Only diabetic HSC-mobilized mice expressed both BrdU and CD31 antigens in the endothelial cells of new capillaries.Conclusion Auto-mobilized adult hematopoietic stem cells advance neovasculature in diabetic retinopathy of mice.

Longitudinal Analysis of DNA Methylation in CD34+ Hematopoietic Progenitors in Myelodysplastic Syndrome

DEFF Research Database (Denmark)

Wong, Yan Fung; Micklem, Chris N; Taguchi, Masataka

2014-01-01

Myelodysplastic syndrome (MDS) is a disorder of hematopoietic stem cells (HSCs) that is often treated with DNA methyltransferase 1 (DNMT1) inhibitors (5-azacytidine [AZA], 5-aza-2'-deoxycytidine), suggesting a role for DNA methylation in disease progression. How DNMT inhibition retards disease...... regulators not expressed within the hematopoietic compartment and was distinct from that observed between healthy hematopoietic cell types. After AZA treatment, we observed only limited DNA demethylation at sites that varied between patients. This suggests that a subset of the stem cell population...... is resistant to AZA and provides a basis for disease relapse. Using gene expression data from patient samples and an in vitro AZA treatment study, we identified differentially methylated genes that can be activated following treatment and that remain silent in the CD34+ stem cell compartment of high-risk MDS...

Depression and anxiety following hematopoietic stem cell transplantation

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Kuba, K; Esser, P; Mehnert, A

2017-01-01

In this prospective multicenter study, we investigated the course of depression and anxiety during hematopoietic stem cell transplantation (HSCT) until 5 years after transplantation adjusting for medical information. Patients were consulted before HSCT (n=239), at 3 months (n=150), 12 months (n=102...

Pharmacoeconomics of Hematopoietic Stem Cell Mobilization : An Overview of Current Evidence and Gaps in the Literature

NARCIS (Netherlands)

Shaughnessy, Paul; Chao, Nelson; Shapiro, Jamie; Walters, Kent; McCarty, John; Abhyankar, Sunil; Shayani, Sepideh; Helmons, Pieter; Leather, Helen; Pazzalia, Amy; Pickard, Simon

Adequate hematopoietic stem cell (HSC) mobilization and collection is required prior to proceeding with high dose chemotherapy and autologous hematopoietic stem cell transplant. Cytokines such as G-CSF, GM-CSF, and peg-filgrastim, alone or in combination with plerixafor, and after chemotherapy have

Human factors and ergonomics for primary care.

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Bowie, Paul; Jeffcott, Shelly

2016-03-01

In the second paper of this series, we provide a brief overview of the scientific discipline of human factors and ergonomics (HFE). Traditionally the HFE focus in healthcare has been in acute hospital settings which are perceived to exhibit characteristics more similar to other high-risk industries already applying related principles and methods. This paper argues that primary care is an area which could benefit extensively from an HFE approach, specifically in improving the performance and well-being of people and organisations. To this end, we define the purpose of HFE, outline its three specialist sub-domains (physical, cognitive and organisational HFE) and provide examples of guiding HFE principles and practices. Additionally, we describe HFE issues of significance to primary care education, improvement and research and outline early plans for building capacity and capability in this setting.

Ultrastructural characterization of primary cilia in pathologically characterized human glioblastoma multiforme (GBM) tumors.

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Moser, Joanna J; Fritzler, Marvin J; Rattner, Jerome B

2014-01-01

Primary cilia are non-motile sensory cytoplasmic organelles that are involved in cell cycle progression. Ultrastructurally, the primary cilium region is complex, with normal ciliogenesis progressing through five distinct morphological stages in human astrocytes. Defects in early stages of ciliogenesis are key features of astrocytoma/glioblastoma cell lines and provided the impetus for the current study which describes the morphology of primary cilia in molecularly characterized human glioblastoma multiforme (GBM) tumors. Seven surgically resected human GBM tissue samples were molecularly characterized according to IDH1/2 mutation status, EGFR amplification status and MGMT promoter methylation status and were examined for primary cilia expression and structure using indirect immunofluorescence and electron microscopy. We report for the first time that primary cilia are disrupted in the early stages of ciliogenesis in human GBM tumors. We confirm that immature primary cilia and basal bodies/centrioles have aberrant ciliogenesis characteristics including absent paired vesicles, misshaped/swollen vesicular hats, abnormal configuration of distal appendages, and discontinuity of centriole microtubular blades. Additionally, the transition zone plate is able to form in the absence of paired vesicles on the distal end of the basal body and when a cilium progresses beyond the early stages of ciliogenesis, it has electron dense material clumped along the transition zone and a darkening of the microtubules at the proximal end of the cilium. Primary cilia play a role in a variety of human cancers. Previously primary cilia structure was perturbed in cultured cell lines derived from astrocytomas/glioblastomas; however there was always some question as to whether these findings were a cell culture phenomena. In this study we confirm that disruptions in ciliogenesis at early stages do occur in GBM tumors and that these ultrastructural findings bear resemblance to those previously

In vivo modelling of normal and pathological human T-cell development

NARCIS (Netherlands)

Wiekmeijer, A.S.

2016-01-01

This thesis describes novel insights in human T-cell development by transplanting human HSPCs in severe immunodeficient NSG mice. First, an in vivo model was optimized to allow engraftment of hematopoietic stem cells derived from human bone marrow. This model was used to study aberrant human T-cell

Hematopoietic Stem Cells from Ts65Dn Mice Are Deficient in the Repair of DNA Double-Strand Breaks.

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Wang, Yingying; Chang, Jianhui; Shao, Lijian; Feng, Wei; Luo, Yi; Chow, Marie; Du, Wei; Meng, Aimin; Zhou, Daohong

2016-06-01

Down syndrome (DS) is a genetic disorder caused by the presence of an extra partial or whole copy of chromosome 21. In addition to musculoskeletal and neurodevelopmental abnormalities, children with DS exhibit various hematologic disorders and have an increased risk of developing acute lymphoblastic leukemia and acute megakaryocytic leukemia. Using the Ts65Dn mouse model, we investigated bone marrow defects caused by trisomy for 132 orthologs of the genes on human chromosome 21. The results showed that, although the total bone marrow cellularity as well as the frequency of hematopoietic progenitor cells (HPCs) was comparable between Ts65Dn mice and their age-matched euploid wild-type (WT) control littermates, human chromosome 21 trisomy led to a significant reduction in hematopoietic stem cell (HSC) numbers and clonogenic function in Ts65Dn mice. We also found that spontaneous DNA double-strand breaks (DSBs) were significantly increased in HSCs from the Ts65Dn mice, which was correlated with the significant reduction in HSC clonogenic activity compared to those from WT controls. Moreover, analysis of the repair kinetics of radiation-induced DSBs revealed that HSCs from Ts65Dn mice were less proficient in DSB repair than the cells from WT controls. This deficiency was associated with a higher sensitivity of Ts65Dn HSCs to radiation-induced suppression of HSC clonogenic activity than that of euploid HSCs. These findings suggest that an additional copy of genes on human chromosome 21 may selectively impair the ability of HSCs to repair DSBs, which may contribute to DS-associated hematological abnormalities and malignancies.

Ionizing radiation induces apoptosis in hematopoietic stem and progenitor cells

International Nuclear Information System (INIS)

Meng, A.; Zhou, D.; Geiger, H.; Zant, G.V.

2003-01-01

The aims of this study was to determine if ionizing radiation (IR) induces apoptosis in hematopoietic stem (HSC) and progenitor cells. Lin-cells were isolated from mouse bone marrow (BM) and pretreated with vehicle or 100 μM z-VAD 1 h prior to exposure to 4 Gy IR. The apoptotic and/or necrotic responses of these cells to IR were analyzed by measuring the annexin V and/or 7-AAD staining in HSC and progenitor populations using flow cytometry, and hematopoietic function of these cells was determined by CAFC assay. Exposure of Lin-cells to IR selectively decreased the numbers of HSC and progenitors in association with an increase in apoptosis in a time-dependent manner. Pretreatment of Lin- cells with z-VAD significantly inhibited IR-induced apoptosis and the decrease in the numbers of HSC and progenitors. However, IR alone or in combination with z-VAD did not lead to a significant increase in necrotic cell death in either HSC or progenitors. In addition, pretreatment of BM cells with z-VAD significantly attenuated IR-induced reduction in the frequencies of day-7, -28 and -35 CAFC. Exposure of HSC and progenitors to IR induces apoptosis. The induction of HSC and progenitor apoptosis contributes to IR-induced suppression of their hematopoietic function

Mitochondrial metabolism in hematopoietic stem cells requires functional FOXO3

Science.gov (United States)

Rimmelé, Pauline; Liang, Raymond; Bigarella, Carolina L; Kocabas, Fatih; Xie, Jingjing; Serasinghe, Madhavika N; Chipuk, Jerry; Sadek, Hesham; Zhang, Cheng Cheng; Ghaffari, Saghi

2015-01-01

Hematopoietic stem cells (HSC) are primarily dormant but have the potential to become highly active on demand to reconstitute blood. This requires a swift metabolic switch from glycolysis to mitochondrial oxidative phosphorylation. Maintenance of low levels of reactive oxygen species (ROS), a by-product of mitochondrial metabolism, is also necessary for sustaining HSC dormancy. Little is known about mechanisms that integrate energy metabolism with hematopoietic stem cell homeostasis. Here, we identify the transcription factor FOXO3 as a new regulator of metabolic adaptation of HSC. ROS are elevated in Foxo3−/− HSC that are defective in their activity. We show that Foxo3−/− HSC are impaired in mitochondrial metabolism independent of ROS levels. These defects are associated with altered expression of mitochondrial/metabolic genes in Foxo3−/− hematopoietic stem and progenitor cells (HSPC). We further show that defects of Foxo3−/− HSC long-term repopulation activity are independent of ROS or mTOR signaling. Our results point to FOXO3 as a potential node that couples mitochondrial metabolism with HSC homeostasis. These findings have critical implications for mechanisms that promote malignant transformation and aging of blood stem and progenitor cells. PMID:26209246

Hematopoietic stem cell transplantation in sickle cell disease: patient selection and special considerations

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Bhatia M

2015-07-01

Full Text Available Monica Bhatia,1 Sujit Sheth21Division of Pediatric Hematology/Oncology/Stem Cell Transplantation, Columbia University Medical Center, 2Division of Pediatric Hematology and Oncology, Weill Cornell Medical College, New York, NY, USAAbstract: Hematopoietic stem cell transplantation remains the only curative treatment currently in use for patients with sickle cell disease (SCD. The first successful hematopoietic stem cell transplantation was performed in 1984. To date, approximately 1,200 transplants have been reported. Given the high prevalence of this disorder in Africa, and its emergence in the developed world through immigration, this number is relatively small. There are many reasons for this; primary among them are the availability of a donor, the risks associated with this complex procedure, and the cost and availability of resources in the developing world. Of these, it is fair to say that the risks associated with the procedure have steadily decreased to the point where, if currently performed in a center with experience using a matched sibling donor, overall survival is close to 100% and event-free survival is over 90%. While there is little controversy around offering hematopoietic stem cell transplantation to symptomatic SCD patients with a matched sibling donor, there is much debate surrounding the use of this modality in “less severe” patients. An overview of the current state of our understanding of the pathology and treatment of SCD is important to show that our current strategy is not having the desired impact on survival of homozygous SCD patients, and should be changed to significantly impact the small proportion of these patients who have matched siblings and could be cured, especially those without overt clinical manifestations. Both patient families and providers must be made to understand the progressive nature of SCD, and should be encouraged to screen full siblings of patients with homozygous SCD for their potential to

Fanconi anemia genes are highly expressed in primitive CD34+ hematopoietic cells

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Brodeur Isabelle

2003-06-01

Full Text Available Abstract Background Fanconi anemia (FA is a complex recessive genetic disease characterized by progressive bone marrow failure (BM and a predisposition to cancer. We have previously shown using the Fancc mouse model that the progressive BM failure results from a hematopoietic stem cell defect suggesting that function of the FA genes may reside in primitive hematopoietic stem cells. Methods Since genes involved in stem cell differentiation and/or maintenance are usually regulated at the transcription level, we used a semiquantitative RT-PCR method to evaluate FA gene transcript levels in purified hematopoietic stem cells. Results We show that most FA genes are highly expressed in primitive CD34-positive and negative cells compared to lower levels in more differentiated cells. However, in CD34- stem cells the Fancc gene was found to be expressed at low levels while Fancg was undetectable in this population. Furthermore, Fancg expression is significantly decreased in Fancc -/- stem cells as compared to wild-type cells while the cancer susceptibility genes Brca1 and Fancd1/Brac2 are upregulated in Fancc-/- hematopoietic cells. Conclusions These results suggest that FA genes are regulated at the mRNA level, that increased Fancc expression in LTS-CD34+ cells correlates with a role at the CD34+ differentiation stage and that lack of Fancc affects the expression of other FA gene, more specifically Fancg and Fancd1/Brca2, through an unknown mechanism.

Bcl11a Deficiency Leads to Hematopoietic Stem Cell Defects with an Aging-like Phenotype

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Sidinh Luc

2016-09-01

Full Text Available B cell CLL/lymphoma 11A (BCL11A is a transcription factor and regulator of hemoglobin switching that has emerged as a promising therapeutic target for sickle cell disease and thalassemia. In the hematopoietic system, BCL11A is required for B lymphopoiesis, yet its role in other hematopoietic cells, especially hematopoietic stem cells (HSCs remains elusive. The extensive expression of BCL11A in hematopoiesis implicates context-dependent roles, highlighting the importance of fully characterizing its function as part of ongoing efforts for stem cell therapy and regenerative medicine. Here, we demonstrate that BCL11A is indispensable for normal HSC function. Bcl11a deficiency results in HSC defects, typically observed in the aging hematopoietic system. We find that downregulation of cyclin-dependent kinase 6 (Cdk6, and the ensuing cell-cycle delay, correlate with HSC dysfunction. Our studies define a mechanism for BCL11A in regulation of HSC function and have important implications for the design of therapeutic approaches to targeting BCL11A.

Multiple primary malignant neoplasms in breast cancer patients in Israel

International Nuclear Information System (INIS)

Schenker, J.G.; Levinsky, R.; Ohel, G.

1984-01-01

The data of an epidemiologic study of multiple primary malignant neoplasms in breast cancer patients in Israel are presented. During the 18-year period of the study 12,302 cases of breast carcinoma were diagnosed, and, of these, 984 patients (8%) had multiple primary malignant tumors. Forty-seven of these patients developed two multiple primary cancers. A significantly higher than expected incidence of second primary cancers occurred at the following five sites: the opposite breast, salivary glands, uterine corpus, ovary, and thyroid. Cancers of the stomach and gallbladder were fewer than expected. Treatment of the breast cancer by irradiation was associated with an increased risk of subsequent cancers of lung and hematopoietic system. The prognosis was mainly influenced by the site and malignancy of the second primary cancer. The incidence of multiple primary malignancies justifies a high level of alertness to this possibility in the follow-up of breast cancer patients

Vascular status in human primary and permanent teeth in health and disease.

Science.gov (United States)

Rodd, Helen D; Boissonade, Fiona M

2005-04-01

The present study sought to compare the vascular status of human primary teeth with that of human permanent teeth, and to determine whether caries or painful pulpitis was associated with changes in vascularity. Coronal pulps were removed from 62 primary and 62 permanent mandibular molars with a known pain history. Teeth were categorized as intact, moderately carious or grossly carious. Pulp sections were labelled with Ulex europaeus I lectin (UEIL), which is a marker of human vascular endothelium. Image analysis was then used to quantify the percentage area of UEIL-labelled tissue (vascularity) and the number of blood vessels present within three regions: the pulp horn, the subodontoblastic region, and the mid-coronal pulp. Only the mid-coronal region of the primary tooth pulp was found to be significantly more vascular than the corresponding area of the permanent tooth pulp. Both dentitions showed a significant increase in vascularity within the pulp horn region with caries progression, but this was not accompanied by an increase in vessel number. There was no correlation between vascularity and pain symptoms. These findings suggest that the primary tooth pulp is more vascular than its successor within the mid-coronal region. However, the functional and clinical significance of this finding remains speculative.

Skeletal Muscle-derived Hematopoietic Stem Cells: Muscular Dystrophy Therapy by Bone Marrow Transplantation

OpenAIRE

Asakura, Atsushi

2012-01-01

For postnatal growth and regeneration of skeletal muscle, satellite cells, a self-renewing pool of muscle stem cells, give rise to daughter myogenic precursor cells that contribute to the formation of new muscle fibers. In addition to this key myogenic cell class, adult skeletal muscle also contains hematopoietic stem cell and progenitor cell populations which can be purified as a side population (SP) fraction or as a hematopoietic marker CD45-positive cell population. These muscle-derived he...

Telomeres and Telomerase in Hematopoietic Dysfunction: Prognostic Implications and Pharmacological Interventions

Directory of Open Access Journals (Sweden)

Theresa Vasko

2017-10-01

Full Text Available Leukocyte telomere length (TL has been suggested as a marker of biological age in healthy individuals, but can also reflect inherited and acquired hematopoietic dysfunctions or indicate an increased turnover of the hematopoietic stem and progenitor cell compartment. In addition, TL is able to predict the response rate of tyrosine kinase inhibitor therapy in chronic myeloid leukemia (CML, indicates clinical outcomes in chronic lymphocytic leukemia (CLL, and can be used as screening tool for genetic sequencing of selected genes in patients with inherited bone marrow failure syndromes (BMFS. In tumor cells and clonal hematopoietic disorders, telomeres are continuously stabilized by reactivation of telomerase, which can selectively be targeted by telomerase-specific therapy. The use of the telomerase inhibitor Imetelstat in patients with essential thrombocythmia or myelofibrosis as well as the use of dendritic cell-based telomerase vaccination in AML patients with complete remissions are promising examples for anti-telomerase targeted strategies in hematologic malignancies. In contrast, the elevation in telomerase levels through treatment with androgens has become an exciting clinical intervention for patients with BMFS. Here, we review recent developments, which highlight the impact of telomeres and telomerase targeted therapies in hematologic dysfunctions.

Low-dose radiation (LDR) induces hematopoietic hormesis: LDR-induced mobilization of hematopoietic progenitor cells into peripheral blood circulation.

Science.gov (United States)

Li, Wei; Wang, Guanjun; Cui, Jiuwei; Xue, Lu; Cai, Lu

2004-11-01

The aim of this study was to investigate the stimulating effect of low-dose radiation (LDR) on bone marrow hematopoietic progenitor cell (HPC) proliferation and peripheral blood mobilization. Mice were exposed to 25- to 100-mGy x-rays. Bone marrow and peripheral blood HPCs (BFU-E, CFU-GM, and c-kit+ cells) were measured, and GM-CSF, G-CSF, and IL-3 protein and mRNA expression were detected using ELISA, slot blot hybridization, and Northern blot methods. To functionally evaluate LDR-stimulated and -mobilized HPCs, repopulation of peripheral blood cells in lethally irradiated recipients after transplantation of LDR-treated donor HPCs was examined by WBC counts, animal survival, and colony-forming units in the recipient spleens (CFUs-S). 75-mGy x-rays induced a maximal stimulation for bone marrow HPC proliferation (CFU-GM and BFU-E formation) 48 hours postirradiation, along with a significant increase in HPC mobilization into peripheral blood 48 to 72 hours postradiation, as shown by increases in CFU-GM formation and proportion of c-kit+ cells in the peripheral mononuclear cells. 75-mGy x-rays also maximally induced increases in G-CSF and GM-CSF mRNA expression in splenocytes and levels of serum GM-CSF. To define the critical role of these hematopoietic-stimulating factors in HPC peripheral mobilization, direct administration of G-CSF at a dose of 300 microg/kg/day or 150 microg/kg/day was applied and found to significantly stimulate GM-CFU formation and increase c-kit+ cells in the peripheral mononuclear cells. More importantly, 75-mGy x-rays plus 150 microg/kg/day G-CSF (LDR/150-G-CSF) produced a similar effect to that of 300 microg/kg/day G-CSF alone. Furthermore, the capability of LDR-mobilized donor HPCs to repopulate blood cells was confirmed in lethally irradiated recipient mice by counting peripheral WBC and CFUs-S. These results suggest that LDR induces hematopoietic hormesis, as demonstrated by HPC proliferation and peripheral mobilization, providing a

Apoptosis in the human periodontal membrane evaluated in primary and permanent teeth

DEFF Research Database (Denmark)

Bille, Marie-Louise Bastholm; Thomsen, Bjarke; Kjær, Inger

2011-01-01

that resorption is connected to apoptosis of the epithelial cells of Malassez. The purpose of this study is to localize cells undergoing apoptosis in the periodontal membrane of human primary and permanent teeth. Materials and methods. Human primary and permanent teeth were examined immunohistochemically...... for apoptosis and epithelial cells of Malassez in the periodontal membrane. All teeth examined were extracted in connection with treatment. Results. Apoptosis was seen in close proximity to the root surface and within the epithelial cells of Malassez. This pattern of apoptotis is similar in the periodontal...... membrane in primary and permanent teeth. Conclusions. The inter-relationship between apoptotis and root resorption cannot be concluded from the present study. Apoptosis seen in close proximity to the root surface presumably corresponds to the highly innervated layer of the periodontal membrane...

Expression and function of PML-RARA in the hematopoietic progenitor cells of Ctsg-PML-RARA mice.

Directory of Open Access Journals (Sweden)

Lukas D Wartman

Full Text Available Because PML-RARA-induced acute promyelocytic leukemia (APL is a morphologically differentiated leukemia, many groups have speculated about whether its leukemic cell of origin is a committed myeloid precursor (e.g. a promyelocyte versus an hematopoietic stem/progenitor cell (HSPC. We originally targeted PML-RARA expression with CTSG regulatory elements, based on the early observation that this gene was maximally expressed in cells with promyelocyte morphology. Here, we show that both Ctsg, and PML-RARA targeted to the Ctsg locus (in Ctsg-PML-RARA mice, are expressed in the purified KLS cells of these mice (KLS = Kit(+Lin(-Sca(+, which are highly enriched for HSPCs, and this expression results in biological effects in multi-lineage competitive repopulation assays. Further, we demonstrate the transcriptional consequences of PML-RARA expression in Ctsg-PML-RARA mice in early myeloid development in other myeloid progenitor compartments [common myeloid progenitors (CMPs and granulocyte/monocyte progenitors (GMPs], which have a distinct gene expression signature compared to wild-type (WT mice. Although PML-RARA is indeed expressed at high levels in the promyelocytes of Ctsg-PML-RARA mice and alters the transcriptional signature of these cells, it does not induce their self-renewal. In sum, these results demonstrate that in the Ctsg-PML-RARA mouse model of APL, PML-RARA is expressed in and affects the function of multipotent progenitor cells. Finally, since PML/Pml is normally expressed in the HSPCs of both humans and mice, and since some human APL samples contain TCR rearrangements and express T lineage genes, we suggest that the very early hematopoietic expression of PML-RARA in this mouse model may closely mimic the physiologic expression pattern of PML-RARA in human APL patients.

The role of apoptosis in the development of AGM hematopoietic stem cells revealed by Bcl-2 overexpression

NARCIS (Netherlands)

C. Orelio; K.N. Harvey; C. Miles; R.A. Oostendorp (Robert); K. van der Horn; E.A. Dzierzak (Elaine)

2004-01-01

textabstractApoptosis is an essential process in embryonic tissue remodeling and adult tissue homeostasis. Within the adult hematopoietic system, it allows for tight regulation of hematopoietic cell subsets. Previously, it was shown that B-cell leukemia 2 (Bcl-2) overexpression in

Reexamination of the role of hematopoietic organs on the ...

African Journals Online (AJOL)

STORAGESEVER

2009-08-04

Aug 4, 2009 ... Sciences, 300 Fenglin Rd. Shanghai 200032, P.R. China. ... Key words: Hematopoietic organ, wing disc, hemocytes, surgical operation, silkworm, ... They were reared on artificial diet at 25°C under a 16 h ..... The image was.

Human embryonic stem cells in culture possess primary cilia with hedgehog signaling machinery

DEFF Research Database (Denmark)

Kiprilov, Enko N; Awan, Aashir; Desprat, Romain

2008-01-01

Human embryonic stem cells (hESCs) are potential therapeutic tools and models of human development. With a growing interest in primary cilia in signal transduction pathways that are crucial for embryological development and tissue differentiation and interest in mechanisms regulating human hESC d...

MR imaging of hematopoietic regions in bone marrow of aplastic anemia. Diagnostic usefulness of opposed phase T1-weighted images

Energy Technology Data Exchange (ETDEWEB)

Amano, Yasuo; Tanabe, Yoshihiro; Amano, Maki; Kumazaki, Tatsuo [Nippon Medical School, Tokyo (Japan)

1996-01-01

The signal intensity of hematopoietic regions in the marrow of aplastic anemia were investigated on opposed phase T1-weighted images (op-T1WI) with a 0.5-Tesla MR unit. Hematopoietic regions were classified into two groups: low intensity hematopoietic areas (LH) isointense to normal marrow and high intensity hematopoietic regions (HH) with higher intensity than normal marrow on op-T1WI. The signal intensity of LH was significantly lower than that of HH on STIR. LH converted into HH with improvement of laboratory data after therapy, whereas HH decreased with impairment of data. HH were hyperintense to cerebrospinal fluid on op-T1WI. These results indicated that the signal intensity of hematopoietic regions on op-T1WI reflected the cellularity in these regions and that aplastic anemia included hypercellular regions relative to normal marrow. (author).

The role of arginine vasopressin in electroacupuncture treatment of primary sciatica in human.

Science.gov (United States)

Zhao, Xue-Yan; Zhang, Qi-Shun; Yang, Jun; Sun, Fang-Jie; Wang, Da-Xin; Wang, Chang-Hong; He, Wei-Ya

2015-08-01

It has been implicated that electroacupuncture can relieve the symptoms of sciatica with the increase of pain threshold in human, and arginine vasopressin (AVP) in the brain rather than the spinal cord and blood circulation participates in antinociception. Our previous study has proven that AVP in the brain played a role in the process of electroacupuncture analgesia in rat. The goal of the present study was to investigate the role of AVP in electroacupuncture in treating primary sciatica in human. The results showed that (1) AVP concentration of cerebrospinal fluid (CSF) (7.5 ± 2.5 pg/ml), not plasma (13.2 ± 4.2 pg/ml) in primary sciatica patients was lower than that in health volunteers (16.1 ± 3.8 pg/ml and 12.3 ± 3.4 pg/ml), although the osmotic pressure in CSF and plasma did not change; (2) electroacupuncture of the bilateral "Zusanli" points (St. 36) for 60 min relieved the pain sensation in primary sciatica patients; (3) electroacupuncture increased the AVP level of CSF, not plasma in primary sciatica patients; and (4) there was the positive correlation between the effect of electroacupuncture relieving the pain and the AVP level of CSF in the primary sciatica patients. The data suggested that central AVP, not peripheral AVP might improve the effect of electroacupuncture treatment of primary sciatica in human, i.e., central AVP might take part in the electroacupuncture relieving the pain sensation in primary sciatica patients. Copyright © 2015 Elsevier B.V. All rights reserved.

Identifying States along the Hematopoietic Stem Cell Differentiation Hierarchy with Single Cell Specificity via Raman Spectroscopy.

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Ilin, Yelena; Choi, Ji Sun; Harley, Brendan A C; Kraft, Mary L

2015-11-17

A major challenge for expanding specific types of hematopoietic cells ex vivo for the treatment of blood cell pathologies is identifying the combinations of cellular and matrix cues that direct hematopoietic stem cells (HSC) to self-renew or differentiate into cell populations ex vivo. Microscale screening platforms enable minimizing the number of rare HSCs required to screen the effects of numerous cues on HSC fate decisions. These platforms create a strong demand for label-free methods that accurately identify the fate decisions of individual hematopoietic cells at specific locations on the platform. We demonstrate the capacity to identify discrete cells along the HSC differentiation hierarchy via multivariate analysis of Raman spectra. Notably, cell state identification is accurate for individual cells and independent of the biophysical properties of the functionalized polyacrylamide gels upon which these cells are cultured. We report partial least-squares discriminant analysis (PLS-DA) models of single cell Raman spectra enable identifying four dissimilar hematopoietic cell populations across the HSC lineage specification. Successful discrimination was obtained for a population enriched for long-term repopulating HSCs (LT-HSCs) versus their more differentiated progeny, including closely related short-term repopulating HSCs (ST-HSCs) and fully differentiated lymphoid (B cells) and myeloid (granulocytes) cells. The lineage-specific differentiation states of cells from these four subpopulations were accurately identified independent of the stiffness of the underlying biomaterial substrate, indicating subtle spectral variations that discriminated these populations were not masked by features from the culture substrate. This approach enables identifying the lineage-specific differentiation stages of hematopoietic cells on biomaterial substrates of differing composition and may facilitate correlating hematopoietic cell fate decisions with the extrinsic cues that

HANPP Collection: Human Appropriation of Net Primary Productivity (HANPP) by Country and Product

Data.gov (United States)

National Aeronautics and Space Administration — The Global Patterns in Human Appropriation of Net Primary Productivity (HANPP) portion of the HANPP Collection represents a digital map of human appropriation of net...

Subsequent donation requests among 2472 unrelated hematopoietic progenitor cell donors are associated with bone marrow harvest

Science.gov (United States)

Lown, Robert N.; Tulpule, Sameer; Russell, Nigel H.; Craddock, Charles F.; Roest, Rochelle; Madrigal, J. Alejandro; Shaw, Bronwen E.

2013-01-01

Approximately 1 in 20 unrelated donors are asked to make a second donation of hematopoietic progenitor cells, the majority for the same patient. Anthony Nolan undertook a study of subsequent hematopoietic progenitor cell donations made by its donors from 2005 to 2011, with the aims of predicting those donors more likely to be called for a second donation, assessing rates of serious adverse reactions and examining harvest yields. This was not a study of factors predictive of second allografts. During the study period 2591 donations were made, of which 120 (4.6%) were subsequent donations. The median time between donations was 179 days (range, 21–4016). Indications for a second allogeneic transplant included primary graft failure (11.7%), secondary graft failure (53.2%), relapse (30.6%) and others (1.8%). On multivariate analysis, bone marrow harvest at first donation was associated with subsequent donation requests (odds ratio 2.00, P=0.001). The rate of serious adverse reactions in donors making a subsequent donation appeared greater than the rate in those making a first donation (relative risk=3.29, P=0.005). Harvest yields per kilogram recipient body weight were equivalent between donations, although females appeared to have a lower yield at the subsequent donation. Knowledge of these factors will help unrelated donor registries to counsel their donors. PMID:23812935

Fumarate hydratase is a critical metabolic regulator of hematopoietic stem cell functions.

Science.gov (United States)

Guitart, Amelie V; Panagopoulou, Theano I; Villacreces, Arnaud; Vukovic, Milica; Sepulveda, Catarina; Allen, Lewis; Carter, Roderick N; van de Lagemaat, Louie N; Morgan, Marcos; Giles, Peter; Sas, Zuzanna; Gonzalez, Marta Vila; Lawson, Hannah; Paris, Jasmin; Edwards-Hicks, Joy; Schaak, Katrin; Subramani, Chithra; Gezer, Deniz; Armesilla-Diaz, Alejandro; Wills, Jimi; Easterbrook, Aaron; Coman, David; So, Chi Wai Eric; O'Carroll, Donal; Vernimmen, Douglas; Rodrigues, Neil P; Pollard, Patrick J; Morton, Nicholas M; Finch, Andrew; Kranc, Kamil R

2017-03-06

Strict regulation of stem cell metabolism is essential for tissue functions and tumor suppression. In this study, we investigated the role of fumarate hydratase (Fh1), a key component of the mitochondrial tricarboxylic acid (TCA) cycle and cytosolic fumarate metabolism, in normal and leukemic hematopoiesis. Hematopoiesis-specific Fh1 deletion (resulting in endogenous fumarate accumulation and a genetic TCA cycle block reflected by decreased maximal mitochondrial respiration) caused lethal fetal liver hematopoietic defects and hematopoietic stem cell (HSC) failure. Reexpression of extramitochondrial Fh1 (which normalized fumarate levels but not maximal mitochondrial respiration) rescued these phenotypes, indicating the causal role of cellular fumarate accumulation. However, HSCs lacking mitochondrial Fh1 (which had normal fumarate levels but defective maximal mitochondrial respiration) failed to self-renew and displayed lymphoid differentiation defects. In contrast, leukemia-initiating cells lacking mitochondrial Fh1 efficiently propagated Meis1 / Hoxa9 -driven leukemia. Thus, we identify novel roles for fumarate metabolism in HSC maintenance and hematopoietic differentiation and reveal a differential requirement for mitochondrial Fh1 in normal hematopoiesis and leukemia propagation. © 2017 Guitart et al.

Tracking Human Immunodeficiency Virus-1 Infection in the Humanized DRAG Mouse Model

Science.gov (United States)

Kim, Jiae; Peachman, Kristina K.; Jobe, Ousman; Morrison, Elaine B.; Allam, Atef; Jagodzinski, Linda; Casares, Sofia A.; Rao, Mangala

2017-01-01

Humanized mice are emerging as an alternative model system to well-established non-human primate (NHP) models for studying human immunodeficiency virus (HIV)-1 biology and pathogenesis. Although both NHP and humanized mice have their own strengths and could never truly reflect the complex human immune system and biology, there are several advantages of using the humanized mice in terms of using primary HIV-1 for infection instead of simian immunodeficiency virus or chimera simian/HIV. Several different types of humanized mice have been developed with varying levels of reconstitution of human CD45+ cells. In this study, we utilized humanized Rag1KO.IL2RγcKO.NOD mice expressing HLA class II (DR4) molecule (DRAG mice) infused with HLA-matched hematopoietic stem cells from umbilical cord blood to study early events after HIV-1 infection, since the mucosal tissues of these mice are highly enriched for human lymphocytes and express the receptors and coreceptors needed for HIV-1 entry. We examined the various tissues on days 4, 7, 14, and 21 after an intravaginal administration of a single dose of purified primary HIV-1. Plasma HIV-1 RNA was detected as early as day 7, with 100% of the animals becoming plasma RNA positive by day 21 post-infection. Single cells were isolated from lymph nodes, bone marrow, spleen, gut, female reproductive tissue, and brain and analyzed for gag RNA and strong stop DNA by quantitative (RT)-PCR. Our data demonstrated the presence of HIV-1 viral RNA and DNA in all of the tissues examined and that the virus was replication competent and spread rapidly. Bone marrow, gut, and lymph nodes were viral RNA positive by day 4 post-infection, while other tissues and plasma became positive typically between 7 and 14 days post-infection. Interestingly, the brain was the last tissue to become HIV-1 viral RNA and DNA positive by day 21 post-infection. These data support the notion that humanized DRAG mice could serve as an excellent model for studying the

Tracking Human Immunodeficiency Virus-1 Infection in the Humanized DRAG Mouse Model

Directory of Open Access Journals (Sweden)

Jiae Kim

2017-10-01

Full Text Available Humanized mice are emerging as an alternative model system to well-established non-human primate (NHP models for studying human immunodeficiency virus (HIV-1 biology and pathogenesis. Although both NHP and humanized mice have their own strengths and could never truly reflect the complex human immune system and biology, there are several advantages of using the humanized mice in terms of using primary HIV-1 for infection instead of simian immunodeficiency virus or chimera simian/HIV. Several different types of humanized mice have been developed with varying levels of reconstitution of human CD45+ cells. In this study, we utilized humanized Rag1KO.IL2RγcKO.NOD mice expressing HLA class II (DR4 molecule (DRAG mice infused with HLA-matched hematopoietic stem cells from umbilical cord blood to study early events after HIV-1 infection, since the mucosal tissues of these mice are highly enriched for human lymphocytes and express the receptors and coreceptors needed for HIV-1 entry. We examined the various tissues on days 4, 7, 14, and 21 after an intravaginal administration of a single dose of purified primary HIV-1. Plasma HIV-1 RNA was detected as early as day 7, with 100% of the animals becoming plasma RNA positive by day 21 post-infection. Single cells were isolated from lymph nodes, bone marrow, spleen, gut, female reproductive tissue, and brain and analyzed for gag RNA and strong stop DNA by quantitative (RT-PCR. Our data demonstrated the presence of HIV-1 viral RNA and DNA in all of the tissues examined and that the virus was replication competent and spread rapidly. Bone marrow, gut, and lymph nodes were viral RNA positive by day 4 post-infection, while other tissues and plasma became positive typically between 7 and 14 days post-infection. Interestingly, the brain was the last tissue to become HIV-1 viral RNA and DNA positive by day 21 post-infection. These data support the notion that humanized DRAG mice could serve as an excellent model

Human mesenchymal stem cells promote CD34+ hematopoietic stem cell proliferation with preserved red blood cell differentiation capacity.

Science.gov (United States)

Lau, Show Xuan; Leong, Yin Yee; Ng, Wai Hoe; Ng, Albert Wee Po; Ismail, Ida Shazrina; Yusoff, Narazah Mohd; Ramasamy, Rajesh; Tan, Jun Jie

2017-06-01

Studies showed that co-transplantation of mesenchymal stem cells (MSCs) and cord blood-derived CD34 + hematopoietic stem cells (HSCs) offered greater therapeutic effects but little is known regarding the effects of human Wharton's jelly derived MSCs on HSC expansion and red blood cell (RBC) generation in vitro. This study aimed to investigate the effects of MSCs on HSC expansion and differentiation. HSCs were co-cultured with MSCs or with 10% MSCs-derived conditioned medium, with HSCs cultured under standard medium served as a control. Cell expansion rates, number of mononuclear cell post-expansion and number of enucleated cells post-differentiation were evaluated. HSCs showed superior proliferation in the presence of MSC with mean expansion rate of 3.5 × 10 8  ± 1.8 × 10 7 after day 7 compared to the conditioned medium and the control group (8.9 × 10 7  ± 1.1 × 10 8 and 7.0 × 10 7  ± 3.3 × 10 6 respectively, P cell was greater compared to earlier passages, indicating successful RBC differentiation. Cord blood-derived CD34 + HSCs can be greatly expanded by co-culturing with MSCs without affecting the RBC differentiation capability, suggesting the importance of direct MSC-HSCs contact in HSC expansion and RBC differentiation. © 2017 International Federation for Cell Biology.

Cytotoxicity and accumulation of ergot alkaloids in human primary cells.

Science.gov (United States)

Mulac, Dennis; Humpf, Hans-Ulrich

2011-04-11

Ergot alkaloids are secondary metabolites produced by fungi of the species Claviceps. Toxic effects after consumption of contaminated grains are described since mediaeval times. Of the more than 40 known ergot alkaloids six are found predominantly. These are ergotamine, ergocornine, ergocryptine, ergocristine, ergosine and ergometrine, along with their corresponding isomeric forms (-inine-forms). Toxic effects are known to be induced by an interaction of the ergot alkaloids as neurotransmitters, like dopamine or serotonin. Nevertheless data concerning cytotoxic effects are missing and therefore a screening of the six main ergot alkaloids was performed in human primary cells in order to evaluate the toxic potential. As it is well known that ergot alkaloids isomerize easily the stability was tested in the cell medium. Based on these results factors were calculated to correct the used concentration values to the biologically active lysergic (-ine) form. These factors range from 1.4 for the most stable compound ergometrine to 5.0 for the most unstable ergot alkaloid ergocristine. With these factors, reflecting the instability, several controverse literature data concerning the toxicity could be explained. To evaluate the cytotoxic effects of ergot alkaloids, human cells in primary culture were used. These cells remain unchanged in contrast to cell lines and the data allow a better comparison to the in vivo situation than using immortalized cell lines. To characterize the effects on primary cells, renal proximal tubule epithelial cells (RPTEC) and normal human astrocytes (NHA) were used. The parameters necrosis (LDH-release) and apoptosis (caspase-3-activation, DNA condensation and fragmentation) were distinguished. The results show that depending on the individual structure of the peptide ergot alkaloids the toxic properties change. While ergometrine as a lysergic acid amide did not show any effect, the peptide ergot alkaloids revealed a different toxic potential. Of

Reciprocal expression of Bmi1 and Mel-18 is associated with functioning of primitive hematopoietic cells.

Science.gov (United States)

Kajiume, Teruyuki; Ohno, Norioki; Sera, Yasuhiko; Kawahara, Yumi; Yuge, Louis; Kobayashi, Masao

2009-07-01

The Polycomb-group (PcG) genes regulate global gene expression in many biological processes, including hematopoiesis, by manipulating specific target genes. It is known that various PcG genes regulate self-renewal of hematopoietic stem cells (HSCs). Here we have shown that the reciprocal expression of PcG proteins regulates self-renewal and differentiation of HSCs. We used murine and human bone marrow cells and evaluated the reciprocal expression of PcG proteins on the basis of their respective intranuclear distributions. PcG-gene expression in HSCs was knocked down by small interfering RNAs. The function of each gene in HSCs was analyzed in vitro and in vivo. Cells were either Bmi1-positive or Mel-18-positive. The Bmi1-positive cells contained very little amounts of Mel-18 and vice versa. The bmi1-knockdown marrow cells did not show HSC function, while the mel-18-knockdown marrow cells showed increased stem cell function. Results of the analysis on human cells were similar to those observed in case of murine cells. In a clinical investigation, transplantation using sources with a low Bmi1 to Mel-18 ratio was associated with early hematopoietic recovery. Reciprocal expression of Bmi1 and Mel-18 regulated HSC function. Here, we observed that expression of the PcG genes-bmi1 and mel-18-is correlated with self-renewal and differentiation of HSCs. Thus, it was suggested that the balance between Bmi1 and Mel-18 regulates self-renewal of HSCs.

Selective expression of a protein-tyrosine kinase, p56lyn, in hematopoietic cells and association with production of human T-cell lymphotropic virus type I

International Nuclear Information System (INIS)

Yamanashi, Yuji; Mori, Shigeo; Inoue, Kazushi; Yamamoto, Tadashi; Toyoshima, Kumao; Yoshida, Mitsuaki; Kishimoto, Tadamitsu

1989-01-01

This paper reports the identification of the lyn gene product, a member of the src-related family of protein-tyrosine kinases, and its expression in hematopoietic cells. A lyn-specific sequence (Arg-25 to Ala-119 of the protein) was expressed in Escherichia coli as a fusion protein with β-galactosidase. Antiserum raised against the fusion protein immunoprecipitated a 56-kDa protein from human B lymphocytes. Incubation of the immunoprecipitate with [γ- 32 P]ATP resulted in the phosphorylation of this protein at tyrosine residues. Immunohistological and immunoblotting analyses showed that the lyn gene product was expressed in lymphatic tissues (spleen and tonsil) and in adult lung, which contains many macrophages. Furthermore, both the transcripts and the protein products of the lyn gene accumulated in macrophages/monocytes, platelets, and B lymphocytes but were not expressed appreciably in granulocytes, erythrocytes, or T lymphocytes, suggesting that lyn gene products function primarily in certain differentiated cells of lymphoid and myeloid lineages

Hematopoietic stem cell fate through metabolic control.

Science.gov (United States)

Ito, Kyoko; Ito, Keisuke

2018-05-25

Hematopoietic stem cells (HSCs) maintain a quiescent state in the bone marrow to preserve their self-renewal capacity, but also undergo cell divisions as required. Organelles such as the mitochondria sustain cumulative damage during these cell divisions, and this damage may eventually compromise the cells' self-renewal capacity. HSC divisions result in either self-renewal or differentiation, with the balance between the two directly impacting hematopoietic homeostasis; but the heterogeneity of available HSC-enriched fractions, together with the technical challenges of observing HSC behavior, has long hindered the analysis of individual HSCs, and prevented the elucidation of this process. However, recent advances in genetic models, metabolomics analyses and single-cell approaches have revealed the contributions made to HSC self-renewal by metabolic cues, mitochondrial biogenesis, and autophagy/mitophagy, which have highlighted mitochondrial quality as a key control factor in the equilibrium of HSCs. A deeper understanding of precisely how specific modes of metabolism control HSC fate at the single cell level is therefore not only of great biological interest, but will have clear clinical implications for the development of therapies for hematological disease. Copyright © 2018. Published by Elsevier Inc.

Complications of hematopoietic stem transplantation: Fungal infections.

Science.gov (United States)

Omrani, Ali S; Almaghrabi, Reem S

2017-12-01

Patients undergoing allogeneic hematopoietic stem cell transplantation (HSCT) are at increased risk of invasive fungal infections, especially during the early neutropenic phase and severe graft-versus-host disease. Mold-active prophylaxis should be limited to the highest risk groups. Empiric antifungal therapy for HSCT with persistent febrile neutropenia is associated with unacceptable response rates, unnecessary antifungal therapy, increased risk of toxicity, and inflated costs. Empiric therapy should not be a substitute for detailed work up to identify the cause of fever in such patients. The improved diagnostic performance of serum biomarkers such as galactomannan and β-D-glucan, as well as polymerase chain reaction assays has allowed the development of diagnostic-driven antifungal therapy strategies for high risk patients. Diagnostic-driven approaches have resulted in reduced unnecessary antifungal exposure, improved diagnosis of invasive fungal disease, and reduced costs without increased risk of mortality. The appropriateness of diagnostic-driven antifungal strategy for individual HSCT centers depends on the availability and turnaround times for diagnostics, multidisciplinary expertise, and the local epidemiology of invasive fungal infections. Echinocandins are the treatment of choice for invasive candidiasis in most HSCT recipients. Fluconazole may be used for the treatment of invasive candidiasis in hemodynamically stable patients with no prior azole exposure. The primary treatment of choice for invasive aspergillosis is voriconazole. Alternatives include isavuconazole and lipid formulations of amphotericin. Currently available evidence does not support routine primary combination antifungal therapy for invasive aspergillosis. However, combination salvage antifungal therapy may be considered in selected patients. Therapeutic drug monitoring is recommended for the majority of HSCT recipients on itraconazole, posaconazole, or voriconazole. Copyright © 2017

Effect of radiation dose-rate on hematopoietic cell engraftment in adult zebrafish.

Directory of Open Access Journals (Sweden)

Tiffany J Glass

Full Text Available Although exceptionally high radiation dose-rates are currently attaining clinical feasibility, there have been relatively few studies reporting the biological consequences of these dose-rates in hematopoietic cell transplant (HCT. In zebrafish models of HCT, preconditioning before transplant is typically achieved through radiation alone. We report the comparison of outcomes in adult zebrafish irradiated with 20 Gy at either 25 or 800 cGy/min in the context of experimental HCT. In non-transplanted irradiated fish we observed no substantial differences between dose-rate groups as assessed by fish mortality, cell death in the kidney, endogenous hematopoietic reconstitution, or gene expression levels of p53 and ddb2 (damage-specific DNA binding protein 2 in the kidney. However, following HCT, recipients conditioned with the higher dose rate showed significantly improved donor-derived engraftment at 9 days post transplant (p ≤ 0.0001, and improved engraftment persisted at 31 days post transplant. Analysis for sdf-1a expression, as well as transplant of hematopoietic cells from cxcr4b -/- zebrafish, (odysseus, cumulatively suggest that the sdf-1a/cxcr4b axis is not required of donor-derived cells for the observed dose-rate effect on engraftment. Overall, the adult zebrafish model of HCT indicates that exceptionally high radiation dose-rates can impact HCT outcome, and offers a new system for radiobiological and mechanistic interrogation of this phenomenon. Key words: Radiation dose rate, Total Marrow Irradiation (TMI, Total body irradiation (TBI, SDF-1, Zebrafish, hematopoietic cell transplant.

Retroviral-mediated gene transfer and expression of human phenylalanine hydroxylase in primary mouse hepatocytes

Energy Technology Data Exchange (ETDEWEB)

Peng, H.; Armentano, D.; Mackenzie-Graham, L.; Shen, R.F.; Darlington, G.; Ledley, F.D.; Woo, S.L.C. (Baylor College of Medicine, Houston, TX (USA))

1988-11-01

Genetic therapy for phenylketonuria (severe phenylalanine hydroxylase deficiency) may require introduction of a normal phenylalanine hydroxylase gene into hepatic cells of patients. The authors report development of a recombinant retrovirus based on the N2 vector for gene transfer and expression of human phenylalanine hydroxylase cDNA in primary mouse hepatocytes. This construct contains an internal promoter of the human {alpha}{sub 1}-antitrypsin gene driving transcription of the phenylalanine hydroxylase cDNA. Primary mouse hepatocytes were isolated from newborn mice, infected with the recombinant virus, and selected for expression of the neomycin-resistance gene. Hepatocytes transformed with the recombinant virus contained high levels of human phenylalanine hydroxylase mRNA transcripts originating from the retroviral and internal promoters. These results demonstrate that the transcriptional regulatory elements of the {alpha}{sub 1} antitrypsin gene retain their tissue-specific function in the recombinant provirus and establish a method for efficient transfer and high-level expression of human phenylalanine hydroxylase in primary hepatocytes.

Retroviral-mediated gene transfer and expression of human phenylalanine hydroxylase in primary mouse hepatocytes

International Nuclear Information System (INIS)

Peng, H.; Armentano, D.; Mackenzie-Graham, L.; Shen, R.F.; Darlington, G.; Ledley, F.D.; Woo, S.L.C.

1988-01-01

Genetic therapy for phenylketonuria (severe phenylalanine hydroxylase deficiency) may require introduction of a normal phenylalanine hydroxylase gene into hepatic cells of patients. The authors report development of a recombinant retrovirus based on the N2 vector for gene transfer and expression of human phenylalanine hydroxylase cDNA in primary mouse hepatocytes. This construct contains an internal promoter of the human α 1 -antitrypsin gene driving transcription of the phenylalanine hydroxylase cDNA. Primary mouse hepatocytes were isolated from newborn mice, infected with the recombinant virus, and selected for expression of the neomycin-resistance gene. Hepatocytes transformed with the recombinant virus contained high levels of human phenylalanine hydroxylase mRNA transcripts originating from the retroviral and internal promoters. These results demonstrate that the transcriptional regulatory elements of the α 1 antitrypsin gene retain their tissue-specific function in the recombinant provirus and establish a method for efficient transfer and high-level expression of human phenylalanine hydroxylase in primary hepatocytes

Mouse monoclonal antibodies against human c-Mpl and characterization for flow cytometry applications.

Science.gov (United States)

Abbott, Christina; Huang, Guo; Ellison, Aaron R; Chen, Ching; Arora, Taruna; Szilvassy, Stephen J; Wei, Ping

2010-04-01

Mouse monoclonal antibodies (MAbs) against human c-Mpl, the cognate receptor for thrombopoietin (TPO), were generated using hybridoma technology and characterized by various assays to demonstrate their specificity and affinity. Two such MAbs, 1.6 and 1.75, were determined to be superior for flow cytometry studies and exhibited double-digit picomolar (pM) affinities to soluble human c-Mpl protein. Both MAbs specifically bound to cells engineered to overexpress human c-Mpl protein, immortalized human hematopoietic cell lines that express endogenous c-Mpl, primary human bone marrow and peripheral blood-derived CD34(+) cells, and purified human platelets. No binding was detected on cell lines that did not express c-Mpl. Receptor competition and siRNA knock-down studies further confirmed the specificity of antibodies 1.6 and 1.75 for human c-Mpl. In contrast to these newly generated MAbs, none of eight commercially available anti-c-Mpl antibodies tested were found to bind specifically to human c-Mpl and were thus shown to be unsuitable for flow cytometry studies. Monoclonal antibodies 1.6 and 1.75 will therefore be useful flow cytometry reagents to detect cell surface c-Mpl expression.

Hematopoietic Acute Radiation Syndrome (Bone marrow syndrome, Aplastic Anemia): Molecular Mechanisms of Radiation Toxicity.

Science.gov (United States)

Popov, Dmitri

Key Words: Aplastic Anemia (AA), Pluripotential Stem Cells (PSC) Introduction: Aplastic Anemia (AA) is a disorder of the pluripotential stem cells involve a decrease in the number of cells of myeloid, erythroid and megakaryotic lineage [Segel et al. 2000 ]. The etiology of AA include idiopathic cases and secondary aplastic anemia after exposure to drugs, toxins, chemicals, viral infections, lympho-proliferative diseases, radiation, genetic causes, myelodisplastic syndromes and hypoplastic anemias, thymomas, lymphomas. [Brodskyet al. 2005.,Modan et al. 1975., Szklo et al. 1975]. Hematopoietic Acute Radiation Syndrome (or Bone marrow syndrome, or Radiation-Acquired Aplastic Anemia) is the acute toxic syndrome which usually occurs with a dose of irradiation between 0.7 and 10 Gy (70- 1000 rads), depending on the species irradiated. [Waselenko et al., 2004]. The etiology of bone morrow damage from high-level radiation exposure results depends on the radiosensitivity of certain bone marrow cell lines. [Waselenko et al. 2004] Aplastic anemia after radiation exposure is a clinical syndrome that results from a marked disorder of bone marrow blood cell production. [Waselenko et al. 2004] Radiation hematotoxicity is mediated via genotoxic and other specific toxic mechanisms, leading to aplasia, cell apoptosis or necrosis, initiation via genetic mechanisms of clonal disorders, in cases such as the acute radiation-acquired form of AA. AA results from radiation injury to pluripotential and multipotential stem cells in the bone marrow. The clinical signs displayed in reticulocytopenia, anemia, granulocytopenia, monocytopenia, and thrombocytopenia. The number of marrow CD34+ cells (multipotential hematopoietic progenitors) and their derivative colony-forming unit{granulocyte-macrophage (CFU-GM) and burst forming unit {erythroid (BFU{E) are reduced markedly in patients with AA. [Guinan 2011, Brodski et al. 2005, Beutler et al.,2000] Cells expressing CD34 (CD34+ cell) are normally

Umbilical cord bloods hematopoietic stem cells ex vivo expansion (the literature review

Directory of Open Access Journals (Sweden)

T. V. Shamanskaya

2012-01-01

Full Text Available Umbilical cord blood (CB is now an attractive source of hematopoietic stem cells (HSCs for transplantation in pediatric and adult patients with various malignant and non-malignant diseases. However, its clinical application is limited by low cells numbers in graft, which correlates with delayed engraftment, an extension of time to platelets and neutrophils recovery and increasing risk of infectious complications. Several strategies have been suggested to overcome this limitation, one of which is obtaining a sufficient number of hematopoietic progenitor cells by ex vivo expansion. Literature review about CB HSCs expansion in given article is presented.

Transmission of clonal chromosomal abnormalities in human hematopoietic stem and progenitor cells surviving radiation exposure

Energy Technology Data Exchange (ETDEWEB)

Kraft, Daniela, E-mail: d.kraft@gsi.de [GSI Helmholtz Center for Heavy Ion Research, Department of Biophysics, Planckstr. 1, 64291 Darmstadt (Germany); Institute for Transfusion Medicine und Immunohematology, DRK-Blutspendedienst Baden-Wuerttemberg—Hessen, Johann Wolfgang Goethe-University Hospital, Sandhofstrasse 1, 60528 Frankfurt (Germany); Ritter, Sylvia, E-mail: s.ritter@gsi.de [GSI Helmholtz Center for Heavy Ion Research, Department of Biophysics, Planckstr. 1, 64291 Darmstadt (Germany); Durante, Marco, E-mail: m.durante@gsi.de [GSI Helmholtz Center for Heavy Ion Research, Department of Biophysics, Planckstr. 1, 64291 Darmstadt (Germany); Institute for Condensed Matter Physics, Physics Department, Technical University Darmstadt, Hochschulstraße 6-8, 64289 Darmstadt (Germany); Seifried, Erhard, E-mail: e.seifried@blutspende.de [Institute for Transfusion Medicine und Immunohematology, DRK-Blutspendedienst Baden-Wuerttemberg—Hessen, Johann Wolfgang Goethe-University Hospital, Sandhofstrasse 1, 60528 Frankfurt (Germany); Fournier, Claudia, E-mail: c.fournier@gsi.de [GSI Helmholtz Center for Heavy Ion Research, Department of Biophysics, Planckstr. 1, 64291 Darmstadt (Germany); Tonn, Torsten, E-mail: t.tonn@blutspende.de [Institute for Transfusion Medicine und Immunohematology, DRK-Blutspendedienst Baden-Wuerttemberg—Hessen, Johann Wolfgang Goethe-University Hospital, Sandhofstrasse 1, 60528 Frankfurt (Germany); Technische Universität Dresden, Med. Fakultät Carl Gustav Carus, Institute for Transfusion Medicine Dresden, German Red Cross Blood Donation Service North-East, Blasewitzer Straße 68/70, 01307 Dresden (Germany)

2015-07-15

Highlights: • Radiation induced formation and transmission of chromosomal aberrations were assessed. • Cytogenetic analysis was performed in human CD34+ HSPC by mFISH. • We report transmission of stable aberrations in irradiated, clonally expanded HSPC. • Unstable aberrations in clonally expanded HSPC occur independently of irradiation. • Carbon ions and X-rays bear a similar risk for propagation of cytogenetic changes. - Abstract: In radiation-induced acute myeloid leukemia (rAML), clonal chromosomal abnormalities are often observed in bone marrow cells of patients, suggesting that their formation is crucial in the development of the disease. Since rAML is considered to originate from hematopoietic stem and progenitor cells (HSPC), we investigated the frequency and spectrum of radiation-induced chromosomal abnormalities in human CD34{sup +} cells. We then measured stable chromosomal abnormalities, a possible biomarker of leukemia risk, in clonally expanded cell populations which were grown for 14 days in a 3D-matrix (CFU-assay). We compared two radiation qualities used in radiotherapy, sparsely ionizing X-rays and densely ionizing carbon ions (29 and 60–85 keV/μm, doses between 0.5 and 4 Gy). Only a negligible number of de novo arising, unstable aberrations (≤0.05 aberrations/cell, 97% breaks) were measured in the descendants of irradiated HSPC. However, stable aberrations were detected in colonies formed by irradiated HSPC. All cells of the affected colonies exhibited one or more identical aberrations, indicating their clonal origin. The majority of the clonal rearrangements (92%) were simple exchanges such as translocations (77%) and pericentric inversions (15%), which are known to contribute to the development of rAML. Carbon ions were more efficient in inducing cell killing (maximum of ∼30–35% apoptotic cells for 2 Gy carbon ions compared to ∼25% for X-rays) and chromosomal aberrations in the first cell-cycle after exposure (∼70% and �

Involvement of the histamine H4 receptor in clozapine-induced hematopoietic toxicity: Vulnerability under granulocytic differentiation of HL-60 cells

International Nuclear Information System (INIS)

Goto, Aya; Mouri, Akihiro; Nagai, Tomoko; Yoshimi, Akira; Ukigai, Mako; Tsubai, Tomomi; Hida, Hirotake; Ozaki, Norio; Noda, Yukihiro

2016-01-01

Clozapine is an effective antipsychotic for treatment-resistant schizophrenia, but can cause fatal hematopoietic toxicity as agranulocytosis. To elucidate the mechanism of hematopoietic toxicity induced by clozapine, we developed an in vitro assay system using HL-60 cells, and investigated the effect on hematopoiesis. HL-60 cells were differentiated by all-trans retinoic acid (ATRA) into three states according to the following hematopoietic process: undifferentiated HL-60 cells, those undergoing granulocytic ATRA-differentiation, and ATRA-differentiated granulocytic cells. Hematopoietic toxicity was evaluated by analyzing cell survival, cell proliferation, granulocytic differentiation, apoptosis, and necrosis. In undifferentiated HL-60 cells and ATRA-differentiated granulocytic cells, both clozapine (50 and 100 μM) and doxorubicin (0.2 µM) decreased the cell survival rate, but olanzapine (1–100 µM) did not. Under granulocytic differentiation for 5 days, clozapine, even at a concentration of 25 μM, decreased survival without affecting granulocytic differentiation, increased caspase activity, and caused apoptosis rather than necrosis. Histamine H 4 receptor mRNA was expressed in HL-60 cells, whereas the expression decreased under granulocytic ATRA-differentiation little by little. Both thioperamide, a histamine H 4 receptor antagonist, and DEVD-FMK, a caspase-3 inhibitor, exerted protection against clozapine-induced survival rate reduction, but not of live cell counts. 4-Methylhistamine, a histamine H 4 receptor agonist, decreased the survival rate and live cell counts, as did clozapine. HL-60 cells under granulocytic differentiation are vulnerable under in vitro assay conditions to hematopoietic toxicity induced by clozapine. Histamine H 4 receptor is involved in the development of clozapine-induced hematopoietic toxicity through apoptosis, and may be a potential target for preventing its occurrence through granulocytic differentiation. - Highlights: • HL-60

Oxidative stress in normal hematopoietic stem cells and leukemia.

Science.gov (United States)

Samimi, Azin; Kalantari, Heybatullah; Lorestani, Marzieh Zeinvand; Shirzad, Reza; Saki, Najmaldin

2018-04-01

Leukemia is developed following the abnormal proliferation of immature hematopoietic cells in the blood when hematopoietic stem cells lose the ability to turn into mature cells at different stages of maturation and differentiation. Leukemia initiating cells are specifically dependent upon the suppression of oxidative stress in the hypoglycemic bone marrow (BM) environment to be able to start their activities. Relevant literature was identified by a PubMed search (2000-2017) of English-language literature using the terms 'oxidative stress,' 'reactive oxygen species,' 'hematopoietic stem cell,' and 'leukemia.' The generation and degradation of free radicals is a main component of the metabolism in aerobic organisms. A certain level of ROS is required for proper cellular function, but values outside this range will result in oxidative stress (OS). Long-term overactivity of reactive oxygen species (ROS) has harmful effects on the function of cells and their vital macromolecules, including the transformation of proteins into autoantigens and increased degradation of protein/DNA, which eventually leads to the change in pathways involved in the development of cancer and several other disorders. According to the metabolic disorders of cancer, the relationship between OS changes, the viability of cancer cells, and their response to chemotherapeutic agents affecting this pathway are undeniable. Recently, studies have been conducted to determine the effect of herbal agents and cancer chemotherapy drugs on oxidative stress pathways. By emphasizing the role of oxidative stress on stem cells in the incidence of leukemia, this paper attempts to state and summarize this subject. © 2018 APMIS. Published by John Wiley & Sons Ltd.

Activation of the canonical Wnt pathway leads to loss of hematopoietic stem cell repopulation and multilineage differentiation block

DEFF Research Database (Denmark)

Kirstetter, Peggy; Anderson, Kristina; Porse, Bo T

2006-01-01

Wnt signaling increases hematopoietic stem cell self-renewal and is activated in both myeloid and lymphoid malignancies, indicating involvement in both normal and malignant hematopoiesis. We report here activated canonical Wnt signaling in the hematopoietic system through conditional expression...... of hematopoietic stem cell function was associated with decreased expression of Cdkn1a (encoding the cell cycle inhibitor p21(cdk)), Sfpi1, Hoxb4 and Bmi1 (encoding the transcription factors PU.1, HoxB4 and Bmi-1, respectively) and altered integrin expression in Lin(-)Sca-1(+)c-Kit(+) cells, whereas PU.1...... of a stable form of beta-catenin. This enforced expression led to hematopoietic failure associated with loss of myeloid lineage commitment at the granulocyte-macrophage progenitor stage; blocked erythrocyte differentiation; disruption of lymphoid development; and loss of repopulating stem cell activity. Loss...

Social network architecture of human immune cells unveiled by quantitative proteomics.

Science.gov (United States)

Rieckmann, Jan C; Geiger, Roger; Hornburg, Daniel; Wolf, Tobias; Kveler, Ksenya; Jarrossay, David; Sallusto, Federica; Shen-Orr, Shai S; Lanzavecchia, Antonio; Mann, Matthias; Meissner, Felix

2017-05-01

The immune system is unique in its dynamic interplay between numerous cell types. However, a system-wide view of how immune cells communicate to protect against disease has not yet been established. We applied high-resolution mass-spectrometry-based proteomics to characterize 28 primary human hematopoietic cell populations in steady and activated states at a depth of >10,000 proteins in total. Protein copy numbers revealed a specialization of immune cells for ligand and receptor expression, thereby connecting distinct immune functions. By integrating total and secreted proteomes, we discovered fundamental intercellular communication structures and previously unknown connections between cell types. Our publicly accessible (http://www.immprot.org/) proteomic resource provides a framework for the orchestration of cellular interplay and a reference for altered communication associated with pathology.

Longitudinal Assessment of Hematopoietic Stem Cell Transplantation and Hyposalivation

DEFF Research Database (Denmark)

Laaksonen, Matti; Ramseier, Adrian; Rovó, Alicia

2011-01-01

Hyposalivation is a common adverse effect of anti-neoplastic therapy of head and neck cancer, causing impaired quality of life and predisposition to oral infections. However, data on the effects of hematopoietic stem cell transplantation (HSCT) on salivary secretion are scarce. The present study...

Covalent immobilization of stem cell factor and stromal derived factor 1α for in vitro culture of hematopoietic progenitor cells.

Science.gov (United States)

Cuchiara, Maude L; Horter, Kelsey L; Banda, Omar A; West, Jennifer L

2013-12-01

Hematopoietic stem cells (HSCs) are currently utilized in the treatment of blood diseases, but widespread application of HSC therapeutics has been hindered by the limited availability of HSCs. With a better understanding of the HSC microenvironment and the ability to precisely recapitulate its components, we may be able to gain control of HSC behavior. In this work we developed a novel, biomimetic PEG hydrogel material as a substrate for this purpose and tested its potential with an anchorage-independent hematopoietic cell line, 32D clone 3 cells. We immobilized a fibronectin-derived adhesive peptide sequence, RGDS; a cytokine critical in HSC self-renewal, stem cell factor (SCF); and a chemokine important in HSC homing and lodging, stromal derived factor 1α (SDF1α), onto the surfaces of poly(ethylene glycol) (PEG) hydrogels. To evaluate the system's capabilities, we observed the effects of the biomolecules on 32D cell adhesion and morphology. We demonstrated that the incorporation of RGDS onto the surfaces promotes 32D cell adhesion in a dose-dependent fashion. We also observed an additive response in adhesion on surfaces with RGDS in combination with either SCF or SDF1α. In addition, the average cell area increased and circularity decreased on gel surfaces containing immobilized SCF or SDF1α, indicating enhanced cell spreading. By recapitulating aspects of the HSC microenvironment using a PEG hydrogel scaffold, we have shown the ability to control the adhesion and spreading of the 32D cells and demonstrated the potential of the system for the culture of primary hematopoietic cell populations. Copyright © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Regulation of the hematopoietic stem cell lifecycle by the endothelial niche.

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Ramalingam, Pradeep; Poulos, Michael G; Butler, Jason M

2017-07-01

Hematopoietic stem cells (HSCs) predominantly reside either in direct contact or in close proximity to the vascular endothelium throughout their lifespan. From the moment of HSC embryonic specification from hemogenic endothelium, endothelial cells (ECs) act as a critical cellular-hub that regulates a vast repertoire of biological processes crucial for HSC maintenance throughout its lifespan. In this review, we will discuss recent findings in endothelial niche-mediated regulation of HSC function during development, aging and regenerative conditions. Studies employing genetic vascular models have unequivocally confirmed that ECs provide the essential instructive cues for HSC emergence during embryonic development as well as adult HSC maintenance during homeostasis and regeneration. Aging of ECs may impair their ability to maintain HSC function contributing to the development of aging-associated hematopoietic deficiencies. These findings have opened up new avenues to explore the therapeutic application of ECs. ECs can be adapted to serve as an instructive platform to expand bona fide HSCs and also utilized as a cellular therapy to promote regeneration of the hematopoietic system following myelosuppressive and myeloablative injuries. ECs provide a fertile niche for maintenance of functional HSCs throughout their lifecycle. An improved understanding of the EC-HSC cross-talk will pave the way for development of EC-directed strategies for improving HSC function during aging.

Respiratory compensation to a primary metabolic alkalosis in humans.

Science.gov (United States)

Feldman, Mark; Alvarez, Naiara M; Trevino, Michael; Weinstein, Gary L

2012-11-01

There is limited and disparate information about the extent of the respiratory compensation (hypoventilation) that occurs in response to a primary metabolic alkalosis in humans. Our aim was to examine the influence of the plasma bicarbonate concentration, the plasma base excess, and the arterial pH on the arterial carbon dioxide tension in 52 adult patients with primary metabolic alkalosis, mostly due to diuretic use or vomiting. Linear regression analysis was used to correlate degrees of alkalosis with arterial carbon dioxide tensions. In this alkalotic cohort, whose arterial plasma bicarbonate averaged 31.6 mEq/l, plasma base excess averaged 7.8 mEq/l, and pH averaged 7.48, both plasma bicarbonate and base excess correlated closely with arterial carbon dioxide tensions (r = 0.97 and 0.96, respectively; p respiratory compensation (hypoventilation) to primary metabolic alkalosis than has been reported in prior smaller studies.

Protective effect study of polysaccharides from tremella fuciformis on hematopoietic function in radiation-injured mice

International Nuclear Information System (INIS)

Xu Wenqing; Chinese Academy of Medical Sciences, Tianjin; Gao Wenyuan; Shen Xiu; Wang Yueying; Liu Peixun

2006-01-01

Objective: To study the protective effects of polysaccharides of Tremella fuciformis on hematopoietic function in radiation-injured mice. Methods; Colony-forming unit of spleen (CFU-S), number of nucleated cells in bone marrow (BMNC) and spleen index were used to investigated the effect of polysacharides from tremella fuciformis at 6 mg/kg, 12 mg/kg, 24 mg/kg on hematopoietic function of mice irradiated with 7.5 Gy 137 Cs γ-rays. Results: On the 9 the day after irradiation compared with the negative control group number of nucleated cells in bone marrow, colony-forming unit of spleen and spleen index of mice have treated with polysaccharides from Tremella fuciformis intraperitoneally for three days prior to irradiation increased markedly. Conclusion: Polysaccharides of tremella fuciformis have protective effect on hematopoietic function of radiation-injured mice. (authors)

Beneficial Effect of the Nutritional Support in Children Who Underwent Hematopoietic Stem Cell Transplant.

Science.gov (United States)

Koç, Nevra; Gündüz, Mehmet; Tavil, Betül; Azik, M Fatih; Coşkun, Zeynep; Yardımcı, Hülya; Uçkan, Duygu; Tunç, Bahattin

2017-08-01

The aim of this study was to evaluate nutritional status in children who underwent hematopoietic stem cell transplant compared with a healthy control group. A secondary aim was to utilize mid-upper arm circumference as a measure of nutritional status in these groups of children. Our study group included 40 children (18 girls, 22 boys) with mean age of 9.2 ± 4.6 years (range, 2-17 y) who underwent hematopoietic stem cell transplant. Our control group consisted of 20 healthy children (9 girls, 11 boys). The children were evaluated at admission to the hospital and followed regularly 3, 6, 9, and 12 months after discharge from the hospital. In the study group, 27 of 40 patients (67.5%) received nutritional support during hematopoietic stem cell transplant, with 15 patients (56%) receiving enteral nutrition, 6 (22%) receiving total parenteral nutrition, and 6 (22%) receiving enteral and total parenteral nutrition. Chronic malnutrition rate in the study group was 47.5% on admission to the hospital, with the control group having a rate of 20%. One year after transplant, the rate decreased to 20% in the study group and 5% in the control group. The mid-upper arm circumference was lower in children in the study group versus the control group at the beginning of the study (P groups at follow-up examinations (P > .05). During follow-up, all anthropometric measurements increased significantly in both groups. Monitoring nutritional status and initiating appropriate nutritional support improved the success of hematopoietic stem cell transplant and provided a more comfortable process during the transplant period. Furthermore, mid-upper arm circumference is a more sensitive, useful, and safer parameter that can be used to measure nutritional status of children who undergo hematopoietic stem cell transplant.

Quantitative assessment of hematopoietic chimerism by quantitative real-time polymerase chain reaction of sequence polymorphism systems after hematopoietic stem cell transplantation.

Science.gov (United States)

Qin, Xiao-ying; Li, Guo-xuan; Qin, Ya-zhen; Wang, Yu; Wang, Feng-rong; Liu, Dai-hong; Xu, Lan-ping; Chen, Huan; Han, Wei; Wang, Jing-zhi; Zhang, Xiao-hui; Li, Jin-lan; Li, Ling-di; Liu, Kai-yan; Huang, Xiao-jun

2011-08-01

Analysis of changes in recipient and donor hematopoietic cell origin is extremely useful to monitor the effect of hematopoietic stem cell transplantation (HSCT) and sequential adoptive immunotherapy by donor lymphocyte infusions. We developed a sensitive, reliable and rapid real-time PCR method based on sequence polymorphism systems to quantitatively assess the hematopoietic chimerism after HSCT. A panel of 29 selected sequence polymorphism (SP) markers was screened by real-time PCR in 101 HSCT patients with leukemia and other hematological diseases. The chimerism kinetics of bone marrow samples of 8 HSCT patients in remission and relapse situations were followed longitudinally. Recipient genotype discrimination was possible in 97.0% (98 of 101) with a mean number of 2.5 (1-7) informative markers per recipient/donor pair. Using serial dilutions of plasmids containing specific SP markers, the linear correlation (r) of 0.99, the slope between -3.2 and -3.7 and the sensitivity of 0.1% were proved reproducible. By this method, it was possible to very accurately detect autologous signals in the range from 0.1% to 30%. The accuracy of the method in the very important range of autologous signals below 5% was extraordinarily high (standard deviation real-time PCR method over short tandem repeat PCR chimerism assays is the absence of PCR competition and plateau biases, with demonstrated greater sensitivity and linearity. Finally, we prospectively analyzed bone marrow samples of 8 patients who received allografts and presented the chimerism kinetics of remission and relapse situations that illustrated the sensitivity level and the promising clinical application of this method. This SP-based real-time PCR assay provides a rapid, sensitive, and accurate quantitative assessment of mixed chimerism that can be useful in predicting graft rejection and early relapse.

Mitochondrial targeting of human O6-methylguanine DNA methyltransferase protects against cell killing by chemotherapeutic alkylating agents.

Science.gov (United States)

Cai, Shanbao; Xu, Yi; Cooper, Ryan J; Ferkowicz, Michael J; Hartwell, Jennifer R; Pollok, Karen E; Kelley, Mark R

2005-04-15

DNA repair capacity of eukaryotic cells has been studied extensively in recent years. Mammalian cells have been engineered to overexpress recombinant nuclear DNA repair proteins from ectopic genes to assess the impact of increased DNA repair capacity on genome stability. This approach has been used in this study to specifically target O(6)-methylguanine DNA methyltransferase (MGMT) to the mitochondria and examine its impact on cell survival after exposure to DNA alkylating agents. Survival of human hematopoietic cell lines and primary hematopoietic CD34(+) committed progenitor cells was monitored because the baseline repair capacity for alkylation-induced DNA damage is typically low due to insufficient expression of MGMT. Increased DNA repair capacity was observed when K562 cells were transfected with nuclear-targeted MGMT (nucl-MGMT) or mitochondrial-targeted MGMT (mito-MGMT). Furthermore, overexpression of mito-MGMT provided greater resistance to cell killing by 1,3-bis (2-chloroethyl)-1-nitrosourea (BCNU) than overexpression of nucl-MGMT. Simultaneous overexpression of mito-MGMT and nucl-MGMT did not enhance the resistance provided by mito-MGMT alone. Overexpression of either mito-MGMT or nucl-MGMT also conferred a similar level of resistance to methyl methanesulfonate (MMS) and temozolomide (TMZ) but simultaneous overexpression in both cellular compartments was neither additive nor synergistic. When human CD34(+) cells were infected with oncoretroviral vectors that targeted O(6)-benzylguanine (6BG)-resistant MGMT (MGMT(P140K)) to the nucleus or the mitochondria, committed progenitors derived from infected cells were resistant to 6BG/BCNU or 6BG/TMZ. These studies indicate that mitochondrial or nuclear targeting of MGMT protects hematopoietic cells against cell killing by BCNU, TMZ, and MMS, which is consistent with the possibility that mitochondrial DNA damage and nuclear DNA damage contribute equally to alkylating agent-induced cell killing during chemotherapy.

A PET Imaging Strategy to Visualize Activated T Cells in Acute Graft-versus-Host Disease Elicited by Allogenic Hematopoietic Cell Transplant.

Science.gov (United States)

Ronald, John A; Kim, Byung-Su; Gowrishankar, Gayatri; Namavari, Mohammad; Alam, Israt S; D'Souza, Aloma; Nishikii, Hidekazu; Chuang, Hui-Yen; Ilovich, Ohad; Lin, Chih-Feng; Reeves, Robert; Shuhendler, Adam; Hoehne, Aileen; Chan, Carmel T; Baker, Jeanette; Yaghoubi, Shahriar S; VanBrocklin, Henry F; Hawkins, Randall; Franc, Benjamin L; Jivan, Salma; Slater, James B; Verdin, Emily F; Gao, Kenneth T; Benjamin, Jonathan; Negrin, Robert; Gambhir, Sanjiv Sam

2017-06-01

A major barrier to successful use of allogeneic hematopoietic cell transplantation is acute graft-versus-host disease (aGVHD), a devastating condition that arises when donor T cells attack host tissues. With current technologies, aGVHD diagnosis is typically made after end-organ injury and often requires invasive tests and tissue biopsies. This affects patient prognosis as treatments are dramatically less effective at late disease stages. Here, we show that a novel PET radiotracer, 2'-deoxy-2'-[18F]fluoro-9-β-D-arabinofuranosylguanine ([18F]F-AraG), targeted toward two salvage kinase pathways preferentially accumulates in activated primary T cells. [18F]F-AraG PET imaging of a murine aGVHD model enabled visualization of secondary lymphoid organs harboring activated donor T cells prior to clinical symptoms. Tracer biodistribution in healthy humans showed favorable kinetics. This new PET strategy has great potential for early aGVHD diagnosis, enabling timely treatments and improved patient outcomes. [18F]F-AraG may be useful for imaging activated T cells in various biomedical applications. Cancer Res; 77(11); 2893-902. ©2017 AACR . ©2017 American Association for Cancer Research.

Nicaraven attenuates radiation-induced injury in hematopoietic stem/progenitor cells in mice.

Directory of Open Access Journals (Sweden)

Miho Kawakatsu

Full Text Available Nicaraven, a chemically synthesized hydroxyl radical-specific scavenger, has been demonstrated to protect against ischemia-reperfusion injury in various organs. We investigated whether nicaraven can attenuate radiation-induced injury in hematopoietic stem/progenitor cells, which is the conmen complication of radiotherapy and one of the major causes of death in sub-acute phase after accidental exposure to high dose radiation. C57BL/6 mice were exposed to 1 Gy γ-ray radiation daily for 5 days in succession (a total of 5 Gy, and given nicaraven or a placebo after each exposure. The mice were sacrificed 2 days after the last radiation treatment, and the protective effects and relevant mechanisms of nicaraven in hematopoietic stem/progenitor cells with radiation-induced damage were investigated by ex vivo examination. We found that post-radiation administration of nicaraven significantly increased the number, improved the colony-forming capacity, and decreased the DNA damage of hematopoietic stem/progenitor cells. The urinary levels of 8-oxo-2'-deoxyguanosine, a marker of DNA oxidation, were significantly lower in mice that were given nicaraven compared with those that received a placebo treatment, although the levels of intracellular and mitochondrial reactive oxygen species in the bone marrow cells did not differ significantly between the two groups. Interestingly, compared with the placebo treatment, the administration of nicaraven significantly decreased the levels of the inflammatory cytokines IL-6 and TNF-α in the plasma of mice. Our data suggest that nicaraven effectively diminished the effects of radiation-induced injury in hematopoietic stem/progenitor cells, which is likely associated with the anti-oxidative and anti-inflammatory properties of this compound.

27-Hydroxycholesterol induces hematopoietic stem cell mobilization and extramedullary hematopoiesis during pregnancy.

Science.gov (United States)

Oguro, Hideyuki; McDonald, Jeffrey G; Zhao, Zhiyu; Umetani, Michihisa; Shaul, Philip W; Morrison, Sean J

2017-09-01

Extramedullary hematopoiesis (EMH) is induced during pregnancy to support rapid expansion of maternal blood volume. EMH activation requires hematopoietic stem cell (HSC) proliferation and mobilization, processes that depend upon estrogen receptor α (ERα) in HSCs. Here we show that treating mice with estradiol to model estradiol increases during pregnancy induced HSC proliferation in the bone marrow but not HSC mobilization. Treatment with the alternative ERα ligand 27-hydroxycholesterol (27HC) induced ERα-dependent HSC mobilization and EMH but not HSC division in the bone marrow. During pregnancy, 27HC levels increased in hematopoietic stem/progenitor cells as a result of CYP27A1, a cholesterol hydroxylase. Cyp27a1-deficient mice had significantly reduced 27HC levels, HSC mobilization, and EMH during pregnancy but normal bone marrow hematopoiesis and EMH in response to bleeding or G-CSF treatment. Distinct hematopoietic stresses thus induce EMH through different mechanisms. Two different ERα ligands, estradiol and 27HC, work together to promote EMH during pregnancy, revealing a collaboration of hormonal and metabolic mechanisms as well as a physiological function for 27HC in normal mice.

Natural Killer Cells Improve Hematopoietic Stem Cell Engraftment by Increasing Stem Cell Clonogenicity In Vitro and in a Humanized Mouse Model.

Science.gov (United States)

Escobedo-Cousin, Michelle; Jackson, Nicola; Laza-Briviesca, Raquel; Ariza-McNaughton, Linda; Luevano, Martha; Derniame, Sophie; Querol, Sergio; Blundell, Michael; Thrasher, Adrian; Soria, Bernat; Cooper, Nichola; Bonnet, Dominique; Madrigal, Alejandro; Saudemont, Aurore

2015-01-01

Cord blood (CB) is increasingly used as a source of hematopoietic stem cells (HSC) for transplantation. Low incidence and severity of graft-versus-host disease (GvHD) and a robust graft-versus-leukemia (GvL) effect are observed following CB transplantation (CBT). However, its main disadvantages are a limited number of HSC per unit, delayed immune reconstitution and a higher incidence of infection. Unmanipulated grafts contain accessory cells that may facilitate HSC engraftment. Therefore, the effects of accessory cells, particularly natural killer (NK) cells, on human CB HSC (CBSC) functions were assessed in vitro and in vivo. CBSC cultured with autologous CB NK cells showed higher levels of CXCR4 expression, a higher migration index and a higher number of colony forming units (CFU) after short-term and long-term cultures. We found that CBSC secreted CXCL9 following interaction with CB NK cells. In addition, recombinant CXCL9 increased CBSC clonogenicity, recapitulating the effect observed of CB NK cells on CBSC. Moreover, the co-infusion of CBSC with CB NK cells led to a higher level of CBSC engraftment in NSG mouse model. The results presented in this work offer the basis for an alternative approach to enhance HSC engraftment that could improve the outcome of CBT.

Inflammation- and tumor-induced anorexia and weight loss require MyD88 in hematopoietic/myeloid cells but not in brain endothelial or neural cells.

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Ruud, Johan; Wilhelms, Daniel Björk; Nilsson, Anna; Eskilsson, Anna; Tang, Yan-Juan; Ströhle, Peter; Caesar, Robert; Schwaninger, Markus; Wunderlich, Thomas; Bäckhed, Fredrik; Engblom, David; Blomqvist, Anders

2013-05-01

Loss of appetite is a hallmark of inflammatory diseases. The underlying mechanisms remain undefined, but it is known that myeloid differentiation primary response gene 88 (MyD88), an adaptor protein critical for Toll-like and IL-1 receptor family signaling, is involved. Here we addressed the question of determining in which cells the MyD88 signaling that results in anorexia development occurs by using chimeric mice and animals with cell-specific deletions. We found that MyD88-knockout mice, which are resistant to bacterial lipopolysaccharide (LPS)-induced anorexia, displayed anorexia when transplanted with wild-type bone marrow cells. Furthermore, mice with a targeted deletion of MyD88 in hematopoietic or myeloid cells were largely protected against LPS-induced anorexia and displayed attenuated weight loss, whereas mice with MyD88 deletion in hepatocytes or in neural cells or the cerebrovascular endothelium developed anorexia and weight loss of similar magnitude as wild-type mice. Furthermore, in a model for cancer-induced anorexia-cachexia, deletion of MyD88 in hematopoietic cells attenuated the anorexia and protected against body weight loss. These findings demonstrate that MyD88-dependent signaling within the brain is not required for eliciting inflammation-induced anorexia. Instead, we identify MyD88 signaling in hematopoietic/myeloid cells as a critical component for acute inflammatory-driven anorexia, as well as for chronic anorexia and weight loss associated with malignant disease.

An evidence-based analysis of epidemiologic associations between lymphatic and hematopoietic cancers and occupational exposure to gasoline.

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Keenan, J J; Gaffney, S; Gross, S A; Ronk, C J; Paustenbach, D J; Galbraith, D; Kerger, B D

2013-10-01

The presence of benzene in motor gasoline has been a health concern for potential increased risk of acute myelogenous leukemia and perhaps other lymphatic/hematopoietic cancers for approximately 40 years. Because of the widespread and increasing use of gasoline by consumers and the high exposure potential of occupational cohorts, a thorough understanding of this issue is important. The current study utilizes an evidence-based approach to examine whether or not the available epidemiologic studies demonstrate a strong and consistent association between occupational exposure to gasoline and lymphatic/hematopoietic cancers. Among 67 epidemiologic studies initially identified, 54 were ranked according to specific criteria relating to the relevance and robustness of each study for answering the research question. The 30 highest-ranked studies were sorted into three tiers of evidence and were analyzed for strength, specificity, consistency, temporality, dose-response trends and coherence. Meta statistics were also calculated for each general and specific lymphatic/hematopoietic cancer category with adequate data. The evidence-based analysis did not confirm any strong and consistent association between occupational exposure to gasoline and lymphatic/hematopoietic cancers based on the epidemiologic studies available to date. These epidemiologic findings, combined with the evidence showing relatively low occupational benzene vapor exposures associated with gasoline formulations during the last three decades, suggest that current motor gasoline formulations are not associated with increased lymphatic/hematopoietic cancer risks related to benzene.

Mobilization of hematopoietic stem cells with highest self-renewal by G-CSF precedes clonogenic cell mobilization peak.

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Winkler, Ingrid G; Wiercinska, Eliza; Barbier, Valerie; Nowlan, Bianca; Bonig, Halvard; Levesque, Jean-Pierre

2016-04-01

Harvest of granulocyte colony-stimulating factor (G-CSF)-mobilized hematopoietic stem cells (HSCs) begins at day 5 of G-CSF administration, when most donors have achieved maximal mobilization. This is based on surrogate markers for HSC mobilization, such as CD34(+) cells and colony-forming activity in blood. However, CD34(+) cells or colony-forming units in culture (CFU-C) are heterogeneous cell populations with hugely divergent long-term repopulation potential on transplantation. HSC behavior is influenced by the vascular bed in the vicinity of which they reside. We hypothesized that G-CSF may mobilize sequentially cells proximal and more distal to bone marrow venous sinuses where HSCs enter the blood. We addressed this question with functional serial transplantation assays using blood and bone marrow after specific time points of G-CSF treatment in mice. We found that in mice, blood collected after only 48 hours of G-CSF administration was as enriched in serially reconstituting HSCs as blood collected at 5 days of G-CSF treatment. Similarly, mobilized Lin(-)CD34(+) cells were relatively enriched in more primitive Lin(-)CD34(+)CD38(-) cells at day 2 of G-CSF treatment compared with later points in half of human donors tested (n = 6). This suggests that in both humans and mice, hematopoietic progenitor and stem cells do not mobilize uniformly according to their maturation stage, with most potent HSCs mobilizing as early as day 2 of G-CSF. Copyright © 2016 ISEH - International Society for Experimental Hematology. Published by Elsevier Inc. All rights reserved.

Bile acid-induced necrosis in primary human hepatocytes and in patients with obstructive cholestasis

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Woolbright, Benjamin L.; Dorko, Kenneth [Department of Pharmacology, Toxicology & Therapeutics, University of Kansas Medical Center, Kansas City, KS (United States); Antoine, Daniel J.; Clarke, Joanna I. [MRC Centre for Drug Safety Science, Department of Molecular and Clinical Pharmacology, Institute of Translational Medicine, University of Liverpool, Liverpool (United Kingdom); Gholami, Parviz [Department of Internal Medicine, University of Kansas Medical Center, Kansas City, KS (United States); Li, Feng [Department of Pharmacology, Toxicology & Therapeutics, University of Kansas Medical Center, Kansas City, KS (United States); Kumer, Sean C.; Schmitt, Timothy M.; Forster, Jameson [Department of Surgery, University of Kansas Medical Center, Kansas City, KS (United States); Fan, Fang [Department of Pathology, University of Kansas Medical Center, Kansas City, KS (United States); Jenkins, Rosalind E.; Park, B. Kevin [MRC Centre for Drug Safety Science, Department of Molecular and Clinical Pharmacology, Institute of Translational Medicine, University of Liverpool, Liverpool (United Kingdom); Hagenbuch, Bruno [Department of Pharmacology, Toxicology & Therapeutics, University of Kansas Medical Center, Kansas City, KS (United States); Olyaee, Mojtaba [Department of Internal Medicine, University of Kansas Medical Center, Kansas City, KS (United States); Jaeschke, Hartmut, E-mail: hjaeschke@kumc.edu [Department of Pharmacology, Toxicology & Therapeutics, University of Kansas Medical Center, Kansas City, KS (United States)

2015-03-15

Accumulation of bile acids is a major mediator of cholestatic liver injury. Recent studies indicate bile acid composition between humans and rodents is dramatically different, as humans have a higher percent of glycine conjugated bile acids and increased chenodeoxycholate content, which increases the hydrophobicity index of bile acids. This increase may lead to direct toxicity that kills hepatocytes, and promotes inflammation. To address this issue, this study assessed how pathophysiological concentrations of bile acids measured in cholestatic patients affected primary human hepatocytes. Individual bile acid levels were determined in serum and bile by UPLC/QTOFMS in patients with extrahepatic cholestasis with, or without, concurrent increases in serum transaminases. Bile acid levels increased in serum of patients with liver injury, while biliary levels decreased, implicating infarction of the biliary tracts. To assess bile acid-induced toxicity in man, primary human hepatocytes were treated with relevant concentrations, derived from patient data, of the model bile acid glycochenodeoxycholic acid (GCDC). Treatment with GCDC resulted in necrosis with no increase in apoptotic parameters. This was recapitulated by treatment with biliary bile acid concentrations, but not serum concentrations. Marked elevations in serum full-length cytokeratin-18, high mobility group box 1 protein (HMGB1), and acetylated HMGB1 confirmed inflammatory necrosis in injured patients; only modest elevations in caspase-cleaved cytokeratin-18 were observed. These data suggest human hepatocytes are more resistant to human-relevant bile acids than rodent hepatocytes, and die through necrosis when exposed to bile acids. These mechanisms of cholestasis in humans are fundamentally different to mechanisms observed in rodent models. - Highlights: • Cholestatic liver injury is due to cytoplasmic bile acid accumulation in hepatocytes. • Primary human hepatocytes are resistant to BA-induced injury

CD45lowc-Kithigh cells have hematopoietic properties in the mouse aorta-gonad-mesonephros region

International Nuclear Information System (INIS)

Nobuhisa, Ikuo; Yamasaki, Shoutarou; Ramadan, Ahmed; Taga, Tetsuya

2012-01-01

Long-term reconstituting hematopoietic stem cells first arise from the aorta of the aorta-gonad-mesonephros (AGM) region in a mouse embryo. We have previously reported that in cultures of the dispersed AGM region, CD45 low c-Kit + cells possess the ability to reconstitute multilineage hematopoietic cells, but investigations are needed to show that this is not a cultured artifact and to clarify when and how this population is present. Based on the expression profile of CD45 and c-Kit in freshly dissociated AGM cells from embryonic day 9.5 (E9.5) to E12.5 and aorta cells in the AGM from E13.5 to E15.5, we defined six cell populations (CD45 − c-Kit − , CD45 − c-Kit low , CD45 − c-Kit high , CD45 low c-Kit high , CD45 high c-Kit high , and CD45 high c-Kit very low ). Among these six populations, CD45 low c-Kit high cells were most able to form hematopoietic cell colonies, but their ability decreased after E11.5 and was undetectable at E13.5 and later. The CD45 low c-Kit high cells showed multipotency in vitro. We demonstrated further enrichment of hematopoietic activity in the Hoechst dye-effluxing side population among the CD45 low c-Kit high cells. Here, we determined that CD45 low c-Kit high cells arise from the lateral plate mesoderm using embryonic stem cell-derived differentiation system. In conclusion, CD45 low c-Kit high cells are the major hematopoietic cells of mouse AGM.

Involvement of the histamine H{sub 4} receptor in clozapine-induced hematopoietic toxicity: Vulnerability under granulocytic differentiation of HL-60 cells

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Goto, Aya; Mouri, Akihiro; Nagai, Tomoko; Yoshimi, Akira; Ukigai, Mako; Tsubai, Tomomi; Hida, Hirotake [Division of Clinical Sciences and Neuropsychopharmacology, Faculty and Graduate School of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku-ku, Nagoya 468-8503 (Japan); Ozaki, Norio [Department of Psychiatry, Graduate School of Medicine, Nagoya University, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550 (Japan); Noda, Yukihiro, E-mail: ynoda@meijo-u.ac.jp [Division of Clinical Sciences and Neuropsychopharmacology, Faculty and Graduate School of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku-ku, Nagoya 468-8503 (Japan)

2016-09-01

Clozapine is an effective antipsychotic for treatment-resistant schizophrenia, but can cause fatal hematopoietic toxicity as agranulocytosis. To elucidate the mechanism of hematopoietic toxicity induced by clozapine, we developed an in vitro assay system using HL-60 cells, and investigated the effect on hematopoiesis. HL-60 cells were differentiated by all-trans retinoic acid (ATRA) into three states according to the following hematopoietic process: undifferentiated HL-60 cells, those undergoing granulocytic ATRA-differentiation, and ATRA-differentiated granulocytic cells. Hematopoietic toxicity was evaluated by analyzing cell survival, cell proliferation, granulocytic differentiation, apoptosis, and necrosis. In undifferentiated HL-60 cells and ATRA-differentiated granulocytic cells, both clozapine (50 and 100 μM) and doxorubicin (0.2 µM) decreased the cell survival rate, but olanzapine (1–100 µM) did not. Under granulocytic differentiation for 5 days, clozapine, even at a concentration of 25 μM, decreased survival without affecting granulocytic differentiation, increased caspase activity, and caused apoptosis rather than necrosis. Histamine H{sub 4} receptor mRNA was expressed in HL-60 cells, whereas the expression decreased under granulocytic ATRA-differentiation little by little. Both thioperamide, a histamine H{sub 4} receptor antagonist, and DEVD-FMK, a caspase-3 inhibitor, exerted protection against clozapine-induced survival rate reduction, but not of live cell counts. 4-Methylhistamine, a histamine H{sub 4} receptor agonist, decreased the survival rate and live cell counts, as did clozapine. HL-60 cells under granulocytic differentiation are vulnerable under in vitro assay conditions to hematopoietic toxicity induced by clozapine. Histamine H{sub 4} receptor is involved in the development of clozapine-induced hematopoietic toxicity through apoptosis, and may be a potential target for preventing its occurrence through granulocytic differentiation

Protein Kinase C Enzymes in the Hematopoietic and Immune Systems.

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Altman, Amnon; Kong, Kok-Fai

2016-05-20

The protein kinase C (PKC) family, discovered in the late 1970s, is composed of at least 10 serine/threonine kinases, divided into three groups based on their molecular architecture and cofactor requirements. PKC enzymes have been conserved throughout evolution and are expressed in virtually all cell types; they represent critical signal transducers regulating cell activation, differentiation, proliferation, death, and effector functions. PKC family members play important roles in a diverse array of hematopoietic and immune responses. This review covers the discovery and history of this enzyme family, discusses the roles of PKC enzymes in the development and effector functions of major hematopoietic and immune cell types, and points out gaps in our knowledge, which should ignite interest and further exploration, ultimately leading to better understanding of this enzyme family and, above all, its role in the many facets of the immune system.

Definitive hematopoietic stem/progenitor cells manifest distinct differentiation output in the zebrafish VDA and PBI.

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Jin, Hao; Sood, Raman; Xu, Jin; Zhen, Fenghua; English, Milton A; Liu, P Paul; Wen, Zilong

2009-02-01

One unique feature of vertebrate definitive hematopoiesis is the ontogenic switching of hematopoietic stem cells from one anatomical compartment or niche to another. In mice, hematopoietic stem cells are believed to originate in the aorta-gonad-mesonephros (AGM), subsequently migrate to the fetal liver (FL) and finally colonize the bone marrow (BM). Yet, the differentiation potential of hematopoietic stem cells within early niches such as the AGM and FL remains incompletely defined. Here, we present in vivo analysis to delineate the differentiation potential of definitive hematopoietic stem/progenitor cells (HSPCs) in the zebrafish AGM and FL analogies, namely the ventral wall of dorsal aorta (VDA) and the posterior blood island (PBI), respectively. Cell fate mapping and analysis of zebrafish runx1(w84x) and vlad tepes (vlt(m651)) mutants revealed that HSPCs in the PBI gave rise to both erythroid and myeloid lineages. However, we surprisingly found that HSPCs in the VDA were not quiescent but were uniquely adapted to generate myeloid but not erythroid lineage cells. We further showed that such distinct differentiation output of HSPCs was, at least in part, ascribed to the different micro-environments present in these two niches. Our results highlight the importance of niche in shaping the differentiation output of developing HSPCs.

The kinetic alteration of hematopoietic stem cells irradiated by ionizing radiation

International Nuclear Information System (INIS)

Ishikawa, Junya; Ojima, Mitsuaki; Kai, Michiaki

2014-01-01

Ionizing radiation (IR) brings oxidative stress, and can cause damages not only on DNA but also proteins and lipids in mammalian cells, and increases the mitochondria-dependent generation of reactive oxygen species (ROS), with the subsequent induction of cell death, cell cycle arrest, and stress related responses. It is well known that IR induces acute myeloid leukemia that originates in hematopoietic cells. However, the mechanisms of leukemogenesis following IR remain unclear. To clarify these mechanisms, it is necessary to quantify the several biological events induced by IR in hematopoietic stem/progenitor cells. In this review, we focus and summarize several recent findings, especially survival/clonogenic potential, cell cycle distribution, generation of ROS, DNA damage/repair, chromosomal abbreviation, and senescence. (author)

Hormone Use for Therapeutic Amenorrhea and Contraception During Hematopoietic Cell Transplantation

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Chang, Katherine; Merideth, Melissa A.; Stratton, Pamela

2015-01-01

There is a growing population of women who have or will undergo hematopoietic stem cell transplant for a variety of malignant and benign conditions. Gynecologists play an important role in addressing the gynecologic and reproductive health concerns for these women throughout the transplant process. As women undergo cell transplantation, they should avoid becoming pregnant and are at risk of uterine bleeding. Thus, counseling about and implementing hormonal treatments such as gonadotropin-releasing hormone agonists, combined hormonal contraceptives, and progestin-only methods help to achieve therapeutic amenorrhea and can serve as contraception during the peritransplant period. In this commentary, we summarize the timing, risks and benefits of the hormonal options just prior, during and for the year after hematopoietic stem cell transplantation. PMID:26348182

Epigenetic regulation of hematopoietic stem cell aging

International Nuclear Information System (INIS)

Beerman, Isabel; Rossi, Derrick J.

2014-01-01

Aging is invariably associated with alterations of the hematopoietic stem cell (HSC) compartment, including loss of functional capacity, altered clonal composition, and changes in lineage contribution. Although accumulation of DNA damage occurs during HSC aging, it is unlikely such consistent aging phenotypes could be solely attributed to changes in DNA integrity. Another mechanism by which heritable traits could contribute to the changes in the functional potential of aged HSCs is through alterations in the epigenetic landscape of adult stem cells. Indeed, recent studies on hematopoietic stem cells have suggested that altered epigenetic profiles are associated with HSC aging and play a key role in modulating the functional potential of HSCs at different stages during ontogeny. Even small changes of the epigenetic landscape can lead to robustly altered expression patterns, either directly by loss of regulatory control or through indirect, additive effects, ultimately leading to transcriptional changes of the stem cells. Potential drivers of such changes in the epigenetic landscape of aged HSCs include proliferative history, DNA damage, and deregulation of key epigenetic enzymes and complexes. This review will focus largely on the two most characterized epigenetic marks – DNA methylation and histone modifications – but will also discuss the potential role of non-coding RNAs in regulating HSC function during aging

Epigenetic regulation of hematopoietic stem cell aging

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Beerman, Isabel, E-mail: isabel.beerman@childrens.harvard.edu [Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA 02138 (United States); Department of Pediatrics, Harvard Medical School, Boston, MA 02115 (United States); Program in Cellular and Molecular Medicine, Division of Hematology/Oncology, Boston Children' s Hospital, MA 02116 (United States); Rossi, Derrick J. [Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA 02138 (United States); Department of Pediatrics, Harvard Medical School, Boston, MA 02115 (United States); Program in Cellular and Molecular Medicine, Division of Hematology/Oncology, Boston Children' s Hospital, MA 02116 (United States)

2014-12-10

Aging is invariably associated with alterations of the hematopoietic stem cell (HSC) compartment, including loss of functional capacity, altered clonal composition, and changes in lineage contribution. Although accumulation of DNA damage occurs during HSC aging, it is unlikely such consistent aging phenotypes could be solely attributed to changes in DNA integrity. Another mechanism by which heritable traits could contribute to the changes in the functional potential of aged HSCs is through alterations in the epigenetic landscape of adult stem cells. Indeed, recent studies on hematopoietic stem cells have suggested that altered epigenetic profiles are associated with HSC aging and play a key role in modulating the functional potential of HSCs at different stages during ontogeny. Even small changes of the epigenetic landscape can lead to robustly altered expression patterns, either directly by loss of regulatory control or through indirect, additive effects, ultimately leading to transcriptional changes of the stem cells. Potential drivers of such changes in the epigenetic landscape of aged HSCs include proliferative history, DNA damage, and deregulation of key epigenetic enzymes and complexes. This review will focus largely on the two most characterized epigenetic marks – DNA methylation and histone modifications – but will also discuss the potential role of non-coding RNAs in regulating HSC function during aging.

Phosphoinositide-3-Kinase Signaling in Human Natural Killer Cells: New Insights from Primary Immunodeficiency

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Emily M. Mace

2018-03-01

Full Text Available Human natural killer (NK cells play a critical role in the control of viral infections and malignancy. Their importance in human health and disease is illustrated by severe viral infections in patients with primary immunodeficiencies that affect NK cell function and/or development. The recent identification of patients with phosphoinositide-3-kinase (PI3K-signaling pathway mutations that can cause primary immunodeficiency provides valuable insight into the role that PI3K signaling plays in human NK cell maturation and lytic function. There is a rich literature that demonstrates a requirement for PI3K in multiple key aspects of NK cell biology, including development/maturation, homing, priming, and function. Here, I briefly review these previous studies and place them in context with recent findings from the study of primary immunodeficiency patients, particularly those with hyperactivating mutations in PI3Kδ signaling.

Experimental study on relationship between expression of SDF-1 and homing of hematopoietic cells

International Nuclear Information System (INIS)

Sun Suping; Cai Jianming; Xiang Yingsong; Zhao Fang; Huang Dingde; Gao Jianguo; Yang Rujun

2002-01-01

Objective: To investigate the role of chemo-attractant SDF-1 in of homing hematopoietic cells. Methods: A mouse allogeneic bone marrow transplantation model and double staining of immunohistochemistry were used in this study. Relationship between expression of chemo-attractant SDF-1 and of homing hematopoietic cells was observed. Results: In bone marrow, SDF-1 was mainly expressed at sites near endosteum, in microvessel endothelium, osteocytes and around donor cells. Contrast to non-irradiation group, SDF-1 was significantly expressed by osteocytes, and at sites near endosteum in the irradiation group, suggesting that pretreatment with irradiation might enhance secretion of SDF-1 by bone marrow stromal cells and SDF-1 could have a close relation with homing cells. Conclusion: Pretreatment with irradiation might be one of the stimulating factors significantly increasing the level of SDF-1 produced by bone marrow stromal cells and the chemo-attractant SDF-1 could play an important role in homing of hematopoietic cells

Ebola virus glycoprotein-mediated anoikis of primary human cardiac microvascular endothelial cells

International Nuclear Information System (INIS)

Ray, Ratna B.; Basu, Arnab; Steele, Robert; Beyene, Aster; McHowat, Jane; Meyer, Keith; Ghosh, Asish K.; Ray, Ranjit

2004-01-01

Ebola virus glycoprotein (EGP) has been implicated for the induction of cytotoxicity and injury in vascular cells. On the other hand, EGP has also been suggested to induce massive cell rounding and detachment from the plastic surface by downregulating cell adhesion molecules without causing cytotoxicity. In this study, we have examined the cytotoxic role of EGP in primary endothelial cells by transduction with a replication-deficient recombinant adenovirus expressing EGP (Ad-EGP). Primary human cardiac microvascular endothelial cells (HCMECs) transduced with Ad-EGP displayed loss of cell adhesion from the plastic surface followed by cell death. Transfer of conditioned medium from EGP-transduced HCMEC into naive cells did not induce loss of adhesion or cell death, suggesting that EGP needs to be expressed intracellularly to exert its cytotoxic effect. Subsequent studies suggested that HCMEC death occurred through apoptosis. Results from this study shed light on the EGP-induced anoikis in primary human cardiac endothelial cells, which may have significant pathological consequences

The Hematopoietic Stem Cell Therapy for Exploration of Space

Science.gov (United States)

Roach, Allana Nicole; Brezo, Jelena

2002-01-01

Astronauts experience severe/invasive disorders caused by space environments. These include hematological/cardiac abnormalities, bone and muscle losses, immunodeficiency, neurological disorders and cancer. While the cause of these symptoms are not yet fully delineated, one possible explanation could be the inhibition of hematopoietic stem cell (HSC) growth and hematopoiesis in space. HSCs differentiate into all types of blood cells, and growing evidence indicates that the HSCs also have the ability to transdifferentiate to various tissues, including muscle, skin, liver, neuronal cells and possibly bone. Therefore, a hypothesis was advanced in this laboratory that the hematopoietic stem cell-based therapy, herein called the hematopoietic stem cell therapy (HSCT), could mitigate some of the disorders described above. Due to the magnitude of this project our laboratory has subdivided it into 3 sections: a) HSCT for space anemia; b) HSCT for muscle and bone losses; and c) HSCT for immunodeficiency. Toward developing the HSCT protocol for space anemia, the HSC transplantation procedure was established using a mouse model of beta thalassemia. In addition, the NASA Rotating Wall Vessel (RWV) culture system was used to grow HSCs in space condition. To investigate the HSCT for muscle loss and bone loss, donor HSCs were genetically marked either by transfecting the beta-galactosidase-containing plasmid, pCMV.SPORT-beta-gal or by preparing from b-galactosidase transgenic mice. The transdifferentiation of HSCs to muscle is traced by the reporter gene expression in the hindlimb suspended mice with some positive outcome, as studied by the X-gal staining procedure. The possible structural contribution of HSCs against muscle loss is being investigated histochemically.

The Lifespan and Turnover of Microglia in the Human Brain

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Pedro Réu

2017-07-01

Full Text Available The hematopoietic system seeds the CNS with microglial progenitor cells during the fetal period, but the subsequent cell generation dynamics and maintenance of this population have been poorly understood. We report that microglia, unlike most other hematopoietic lineages, renew slowly at a median rate of 28% per year, and some microglia last for more than two decades. Furthermore, we find no evidence for the existence of a substantial population of quiescent long-lived cells, meaning that the microglia population in the human brain is sustained by continuous slow turnover throughout adult life.