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Sample records for hemopoietic precursor cells

  1. Hemopoietic cell precursor responses to erythropoietin in plasma clot cultures

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    Kennedy, W.L.

    1979-01-01

    The time dependence of the response of mouse bone marrow cells to erythropoietin (Ep) in vitro was studied. Experiments include studies on the Ep response of marrow cells from normal, plethoric, or bled mice. Results with normal marrow reveal: (1) Not all erythroid precursors (CFU-E) are alike in their response to Ep. A significant number of the precursors develop to a mature erythroid colony after very short Ep exposures, but they account for only approx. 13% of the total colonies generated when Ep is active for 48 hrs. If Ep is active more than 6 hrs, a second population of erythroid colonies emerges at a nearly constant rate until the end of the culture. Full erythroid colony production requires prolonged exposure to erythropoietin. (2) The longer erythropoietin is actively present, the larger the number of erythroid colonies that reach 17 cells or more. Two distinct populations of immediate erythroid precursors are also present in marrow from plethoric mice. In these mice, total colony numbers are equal to or below those obtained from normal mice. However, the population of fast-responding CFU-E is consistently decreased to 10 to 20% of that found in normal marrow. The remaining colonies are formed from plethoric marrow at a rate equal to normal marrow. With increasing Ep exposures, the number of large colonies produced increases. From the marrow of bled mice, total erythroid colony production is equal to or above that of normal marrow. Two populations of colony-forming cells are again evident, with the fast-responding CFU-E being below normal levels. The lack of colonies from this group was compensated in bled mice by rapid colony production in the second population. A real increase in numbers of precursors present in this pool increased the rate of colony production in culture to twice that of normal marrow. The number of large colonies obtained from bled mice was again increased as the Ep exposure was lengthened. (ERB)

  2. Hemopoietic stem cell mobilization in mice

    NARCIS (Netherlands)

    W.J. Molendijk

    1987-01-01

    textabstractIn mice hemopoietic stem cells and progenitor cells are almost totally confined to the bone marrow and spleen. Only small numbers can be detected in the peripheral blood. Relatively little is known about the mechanism(s) modulating the circulation and mobilization of stem cells. At

  3. Effects of hemopoietic growth factors on stem cells in vitro.

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    Ogawa, M

    1989-09-01

    The central feature of hemopoiesis is the lifelong, stable cell renewal. This process is supported by hemopoietic stem cells, which in the steady-state appear to be dormant in cell cycling. The entry into cell cycle of the dormant stem cells may be promoted by such factors as IL-1, IL-6, and G-CSF. Available evidence indicates that the effects of IL-1 on stem cells are indirectly mediated in part by IL-6 and G-CSF. Once the stem cells leave G0 and begin proliferation, the subsequent process is characterized by continued proliferation and differentiation. While several models of stem cell differentiation have been proposed, micromanipulation studies of individual progenitors suggest that the commitment of multipotential progenitors to single lineages is a stochastic (random) process. The proliferation of early hemopoietic progenitors appears to be supported by IL-3, IL-4, and/or GM-CSF. Once the progenitors are committed to individual lineages, the subsequent maturation process appears to be supported by late-acting, lineage-specific factors such as Ep (for erythropoiesis), G-CSF (for neutrophil production), and IL-5 (for eosinophilopoiesis). Thus, hemopoietic proliferation appears to be regulated by a cascade of factors directed at different developmental stages.

  4. The stem cell antigen CD34 functions as a regulator of hemopoietic cell adhesion

    NARCIS (Netherlands)

    L. Healy (Lyn); G. May (Gillian); K. Gale (Karin); F.G. Grosveld (Frank); M.F. Greaves (Mel); T. Enver (Tariq)

    1995-01-01

    markdownabstractAlthough the CD34 antigen is widely used in the identification and purification of hemopoietic stem and progenitor cells, its function within hemopoiesis is unknown. We have investigated this issue by ectopically expressing human (hu) CD34 on the surface of murine hemopoietic cells.

  5. Hemopoietic stem cells: stochastic differentiation and humoral control of proliferation.

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    Ogawa, M

    1989-03-01

    The central feature of hemopoiesis is life-long, stable cell renewal. This process is supported by hemopoietic stem cells which, in the steady state, appear to be dormant in cell cycling. The entry into cell cycle of the dormant stem cells may be promoted by such factors as interleukin-1, interleukin-6 (IL-6), and granulocyte colony-stimulating factor (G-CSF). Once the stem cells leave G0 and begin proliferation, the subsequent process is characterized by continued proliferation and differentiation. While several models of stem cell differentiation have been proposed, micromanipulation studies of individual progenitors suggest that the commitment of multipotential progenitors to single lineages is a random (stochastic) process. The proliferation of early hemopoietic progenitors requires the presence of interleukin-3 (IL-3), and the intermediate process appears to be supported by granulocyte/macrophage colony-stimulating factor (GM-CSF). Once the progenitors are committed to individual lineages, the subsequent maturation process appears to be supported by late-acting, lineage-specific factors such as erythropoietin and G-CSF. Synthesis of a hemopoietic factor may take place in different cell types and is regulated by multiple factors. The physiological regulator of erythropoiesis is erythropoietin, which, by a feedback mechanism, provides fine control of erythrocyte production. Feedback mechanisms for leukocyte production have not been identified. It is possible that there is no feedback regulator of leukopoiesis. In this model, leukocyte production in the steady state is maintained at a genetically determined level. When an infection occurs, the bacterial lipopolysaccharides may augment the production of interleukin 1 alpha and beta, tumor necrosis factor, macrophage colony-stimulating factor, etc.(ABSTRACT TRUNCATED AT 250 WORDS)

  6. Stem Cell Emergence and Hemopoietic Activity Are Incompatible in Mouse Intraembryonic Sites

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    Godin, Isabelle; Garcia-Porrero, Juan Antonio; Dieterlen-Lièvre, Françoise; Cumano, Ana

    1999-01-01

    In the mouse embryo, the generation of candidate progenitors for long-lasting hemopoiesis has been reported in the paraaortic splanchnopleura (P-Sp)/aorta-gonad-mesonephros (AGM) region. Here, we address the following question: can the P-Sp/AGM environment support hemopoietic differentiation as well as generate stem cells, and, conversely, are other sites where hemopoietic differentiation occurs capable of generating stem cells? Although P-Sp/AGM generates de novo hemopoietic stem cells between 9.5 and 12.5 days post coitus (dpc), we show here that it does not support hemopoietic differentiation. Among mesoderm-derived sites, spleen and omentum were shown to be colonized by exogenous cells in the same fashion as the fetal liver. Cells colonizing the spleen were multipotent and pursued their evolution to committed progenitors in this organ. In contrast, the omentum, which was colonized by lymphoid-committed progenitors that did not expand, cannot be considered as a hemopoietic organ. From these data, stem cell generation appears incompatible with hemopoietic activity. At the peak of hemopoietic progenitor production in the P-Sp/AGM, between 10.5 and 11.5 dpc, multipotent cells were found at the exceptional frequency of 1 out of 12 total cells and 1 out of 4 AA4.1+ cells. Thus, progenitors within this region constitute a pool of undifferentiated hemopoietic cells readily accessible for characterization. PMID:10429669

  7. Trisomic hemopoietic stem cells of fetal origin restore hemopoiesis in lethally irradiated mice

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    Herbst, E.W. (Institut fuer Pathologie, Luebeck, Germany); Pluznik, D.H.; Gropp, A.; Uthgenannt, H.

    1981-03-13

    Autosomal trisomy in the mouse is invariably associated with fetal or early postnatal death. Hemopoietic stem cells from fetuses trisomic for chromosome 12 or 19 can be rescued by transplantation into lethally irradiated mice. These trisomic cells restore hemopoiesis, including lymphopoiesis, in the irradiated mice and establish a permanent and almost complete engraftment. There is no evidence that hemopoietic cells with trisomy 12 or 19 are cytogenetically unstable.

  8. Colony-forming activity of unipotent hemopoietic precursors under the effect of nanosized ferrites in a constant magnetic field in vitro.

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    Khlusov, I A; Zagrebin, L V; Shestov, S S; Itin, V I; Sedoi, V S; Feduschak, T A; Terekhova, O G; Magaeva, A A; Naiden, E P; Antipov, S A; Puchkovskaya, E S; Slepchenko, G B; Sukhikh, G T

    2008-01-01

    We studied in vitro effect of ferrimagnetic nanoparticles in a dose of 3 mg/liter (10 maximum permissible concentrations) on colony-forming capacity of bone marrow granulocytic and monocytic precursors in a constant magnetic field at magnetic field intensity of 200 Oe. We tested powders obtained by the methods of electrical explosion of conductors (magnetite and a mixture of hematite with magnetite) or mechanochemical synthesis (cobalt ferrite). According to electron microscopy, size of particles was within 6-65 nm. Specific effect of nanopowders on functional properties of hemopoietic and stromal cells were demonstrated; this effect was not related to dissolution of these powders, but had a complex nature. It depends on the size and magnetic characteristics of powder particles, the route and dose of administration, and the presence of external magnetic field. It was emphasized that in multicellular systems a reaction of committed hemopoietic precursors mediated via cells (factors) of microenvironment cannot be excluded, the state of this system varying in different individuals and under different conditions. Our data open new vistas for the creation and targeted use of nanosized materials and technologies for individual therapy in the context of personalized medicine.

  9. The nature and function of fibroblastoid reticular cells in the hemopoietic stroma

    NARCIS (Netherlands)

    A.H. Piersma (Aldert)

    1985-01-01

    textabstractThe experimental work of this thesis, described in the appendix papers, is aimed at characterization of the nature and function of fibroblastic reticular cells in the hemopoietic stroma. A number of experimental models was employed to elucidate different aspects of these cells. In the

  10. Jacobsen distal 11q deletion syndrome with a myelodysplastic change of hemopoietic cells.

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    Lin, J H; Hou, J W; Teng, R J; Tien, H F; Lin, K H

    1998-02-03

    We describe a male infant with unusual facial appearance, relative pancytopenia, bilateral simian creases, and an accessory nipple. Cytogenetic analysis showed deletion of the long arm of chromosome 11 [46,XY,del(11)(pter-->q23.2:)]. Bone-marrow study showed a myelodysplastic change of hemopoietic cells compatible with peripheral blood findings. Pachygyria of the temporal and frontal lobes was demonstrated by magnetic resonance image (MRI) of the brain. We present our findings in order to contribute to the information on 11q23 deletion.

  11. Clinico-serologic co-relation in bi-directional ABO incompatible hemopoietic stem cell transplantation

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    Sabita Basu

    2015-01-01

    Full Text Available Background: The ABO blood group system is of prime significance in red cell transfusion and organ transplantation. However, ABO compatibility is not critical in allogenic hemopoietic stem cell transplantation (HSCT and approximately 40-50% of hemopoietic stem cell transplants are ABO incompatible. This incompatibility may be major, minor or bi-directional. Though there are descriptions of transfusion practice and protocols in ABO incompatible HSCT, there are considerable variations and transfusion support in these patients can be very challenging. Aims: The immunohematologic observations in two cases of bi-directional ABO incompatible HSCT have been described, and clinico-serologic correlation has been attempted. Materials and Methods: In both cases, peripheral blood stem cell harvests were obtained using the Cobe spectra cell separator. Immunohematologic assessments in the donor and recipient were done as a part of pre HSCT evaluation. Both the standard tube technique and column agglutination method (Ortho Biovue Micro Bead System was used. Antibody screen was done by column agglutination method using three cell panel (Surgiscreen cells. Isoagglutinin titration was done by the master dilution method and standard validated techniques were used. Results: The pattern of laboratory findings in the two cases was different and so were the clinical outcomes. Although there was early engraftment in the first case, the second case developed pure red cell aplasia and this was well-reflected in the immunohematologic assessments. Conclusion: Immunohematologic assessment correlated well with the clinical picture and could be used to predict clinical outcome and onset of complications in ABO incompatible HSCT.

  12. Modulation of beta1-integrins on hemopoietic progenitor cells after allergen challenge in asthmatic subjects.

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    Catalli, Adriana E; Thomson, Jennifer V; Babirad, Irene M; Duong, Mylinh; Doyle, Tracey M; Howie, Karen J; Newbold, Paul; Craggs, Richard I; Foster, Martyn; Gauvreau, Gail M; O'Byrne, Paul M; Sehmi, Roma

    2008-10-01

    Mobilization of hemopoietic progenitor cells from the bone marrow (BM) is a feature of inflammatory asthmatic responses. Understanding the mechanisms regulating progenitor cell mobilization and trafficking to the peripheral circulation might be important for the development of effective asthma therapies. We investigated the role of adhesion molecules in the mobilization of hemopoietic progenitor cells from the BM during an allergen-induced asthmatic response. BM and peripheral blood samples were obtained from dual-responders with mild asthma before and at several time points after allergen challenge. Fluctuations in expression and adhesive properties of beta1- and beta2-integrins on CD34(+)CD45(+) progenitor cells were assessed by using flow cytometry and adhesion to protein-coated wells, respectively. On BM-derived CD34(+)CD45(+) cells, expression of very late antigen (VLA) 4, but not VLA-5 or Mac-1, decreased significantly 24 hours after allergen challenge and had begun to recover by 48 hours after challenge. In peripheral blood allergen challenge induced a significant decrease in VLA-4 levels after 6 hours, which had not recovered by 96 hours after challenge. Similarly, VLA-5 expression decreased, most prominently at 72 to 96 hours after allergen challenge. In contrast, Mac-1 levels did not change. Chemokine-stimulated adhesion of BM-derived CD34(+)CD45(+) cells to fibronectin was significantly attenuated 24 hours after challenge. Furthermore, adhesion to fibronectin and vascular cell adhesion molecule 1 was greatly reduced by anti-VLA-4 or anti-VLA-5 antibodies. Preferential downregulation of beta1-integrin expression on progenitor cells can reduce the tethering forces to BM components, thus facilitating their egress to the peripheral circulation during an allergic inflammatory response.

  13. Microbiology and epidemiology of oral yeast colonization in hemopoietic progenitor cell transplant recipients.

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    Westbrook, Steven D; Kirkpatrick, William R; Wiederhold, Nathan P; Freytes, Cesar O; Toro, Juan J; Patterson, Thomas F; Redding, Spencer W

    2013-03-01

    We monitored the epidemiology and microbiology of oral yeast colonization in patients undergoing hemopoietic progenitor cell transplantation (HPCT) to examine associations between yeast colonization and oral mucositis. One hundred twenty-one consecutive HPCT patients were sampled for oral yeasts prior to fluconazole (FLC) prophylaxis, at transplantation, and weekly until discharge. Clinical oral mucositis screenings were performed triweekly. Yeast colonization was evident at 216 of 510 total visits. Candida albicans and Candida glabrata were the predominant organisms. Eight patients showed elevated minimal inhibitory concentrations to FLC. One patient developed fungal septicemia. Patients with oral mucositis assessment scale scores oral yeasts in HPCT recipients. FLC-resistant yeasts do emerge and can be the source of fungal sepsis. A positive association was not shown between yeast colonization and the presence or severity of oral mucositis. Copyright © 2013 Elsevier Inc. All rights reserved.

  14. Bone marrow MR imaging as predictors of outcome in hemopoietic stem cell transplantation

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    Shen, Jun; Cheng, Li-Na; Duan, Xiao-Hui; Liang, Bi-Ling [Sun Yat-sen University, Department of Radiology, Guangzhou, Guangdong (China); Second Affiliated Hospital, Guangzhou, Guangdong (China); Griffith, James F. [Chinese University of Hong Kong, Prince of Wales Hospital, Department of Diagnostic Radiology and Organ Imaging, Shatin, Hong Kong SAR (China); Xu, Hong-Gui [Sun Yat-sen University, Department of Pediatrics, Guangzhou, Guangdong (China); Second Affiliated Hospital, Guangzhou, Guangdong (China)

    2008-09-15

    The purpose of this study is to investigate the role of femoral marrow MR imaging as predictor of outcome for hemopoietic stem cell transplantation (HSCT) in beta-thalassemia major. MR imaging of the proximal femur, including T1- and T2-weighted spin echo and short-tau inversion recovery and in-phase and out-of-phase fast field echo images, was prospectively performed in 27 thalassemia major patients being prepared for HSCT. The area of red marrow and its percentage of the proximal femur were measured, and the presence of marrow hemosiderosis was assessed. Age-adjusted multivariate logistic regression was used to determine the relationship between red marrow area percentage and marrow hemosiderosis and HSCT outcome. Red area percentage were less in patients with successful (90.25{+-}4.14%) compared to unsuccessful transplants (94.54% {+-}2.93%; p=0.01). Red marrow area percentage correlated positively with duration of symptoms(r=0.428, p=0.026) and serum ferritin (r=0.511, p=0.006). In multivariate-adjusted logistic regression analyses, red marrow area percentage was significantly inversely associated with successful HSCT (OR=1.383, 95% CI: 1.059-1.805, p=0.005). Marrow hemosidersosis and duration of sympotms and serum ferritin were not associated with HSCT outcome(p=0.174, 0.974, 0.762, respectively). Red marrow area percentage of proximal femur on MR imaging is a useful predictor of HSCT outcome. (orig.)

  15. A stochastic model of self-renewal and commitment to differentiation of the primitive hemopoietic stem cells in culture.

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    Nakahata, T; Gross, A J; Ogawa, M

    1982-12-01

    We recently identified a murine hemopoietic stem cell colony which consists of undifferentiated (blast) cells and appears to be more primitive than CFU-GEMM in the stem cell hierarchy. The progenitors for the colony which we termed "stem cell colony" possess an extensive self-renewal capacity and the ability to generate many secondary multipotential hemopoietic colonies in culture. We replated a total of 68 stem cell colonies from cultures of murine spleen cells and analyzed the number of stem cell--and granulocyte(neutrophil)-erythrocyte-macrophage-megakaryocyte (GEMM) colony-forming cells in individual stem cell colonies. Of the 68 stem cell colonies, 35 contained progenitors (abbreviated as "S"-cells) for stem cell colonies. The distributions of S-cells and CFU-GEMM in individual stem cell colonies were extremely heterogeneous. Neither the frequency distributions of S-cells nor CFU-GEMM in stem cell colonies could be fitted well by Poisson distribution. Rather, the frequency distribution of the s-cells could be approximated by a geometric distribution and that of CFU-GEMM by an exponential distribution, both of which are variates of the gamma distribution. Our observations are in agreement with those on the distributions of CFU-S in individual spleen colonies and provided support for a stochastic model for stem cell self-renewal and commitment in culture. Application of the theory of the branching process to the distribution of S-cells revealed a distributional parameter "p" of 0.589 which is also in agreement with the earlier report on the p value for reproduction of CFU-S.

  16. Central and peripheral nervous system immune mediated demyelinating disease after allogeneic hemopoietic stem cell transplantation for hematologic disease.

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    Delios, Anna Maria; Rosenblum, Marc; Jakubowski, Ann A; DeAngelis, Lisa M

    2012-11-01

    Immune mediated demyelinating disease (IMDD) after allogeneic hemopoietic stem cell transplant (HSCT) is rare and its etiology unclear. In this retrospective study, we identified patients who underwent HSCT between January 1992 and December 2010 and had IMDD post transplant. A total of 1,484 patients received HSCT and 7 (0.5 %) suffered from IMDD; five were men, and the median age was 54 years (range, 29-64 years). HSCT treated acute myeloid leukemia (n = 5), myelodysplastic syndrome (n = 1), and Waldenström macroglobulinemia (n = 1). All received an HLA matched donor graft, related (6), unrelated (1); from the bone marrow (1), peripheral blood stem cell (6); and T-cell depleted, ex vivo (6) or in vivo (1). The median time from transplant to neurologic symptoms was 120 days (range, 60-390 days). Three had acute demyelinating encephalomyelitis (ADEM), three acute inflammatory demyelinating polyradiculopathy (AIDP) and one autonomic neuropathy. Four of six patients tested had hemopoietic mixed chimerism prior to neurologic symptoms and low CD4(+) T-cell counts, median 76 (15-500 cells/μL). Two patients had simultaneous systemic graft versus host disease (GVHD). Two patients with ADEM had a spinal cord or brain biopsy which revealed demyelination. No patients had a viral etiology identified in the cerebrospinal fluid. Patients were treated with IV immunoglobulin, high dose steroids and/or rituximab. Five patients had a significant recovery. Response to immune modulators suggests an immune-based etiology. The incidence of de novo autoimmune disease after HSCT for hematological diseases is rare and may be difficult to differentiate from GVHD.

  17. Production of two hemopoietic growth factors is differentially regulated in single T lymphocytes activated with an anti-T cell receptor antibody

    DEFF Research Database (Denmark)

    Kelso, A; Owens, T

    1988-01-01

    A method has been developed to measure the production by single activated T lymphocytes of two hemopoietic growth factors, granulocyte-macrophage CSF (GM-CSF) and multipotential CSF (multi-CSF or IL-3). When individual cells of the L3T4 (CD4)+ F23.1+ T cell clone E9.D4 were transferred...... by micromanipulation into wells coated with the monoclonal anti-T cell receptor antibody F23.1, up to 90% of cells produced CSF as detected by CSF-dependent hemopoietic cell lines. Production occurred in the absence of proliferation and did not require the addition of accessory cells or IL-2. Both the frequency of CSF...

  18. Quantification of erythroid and granulocytic precursor cells in plateletpheresis residues

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    Abboud, C.N.; Brennan, J.K.; Lichtman, M.A.; Nusbacher, J.

    1978-01-01

    Mononuclear cell fractions of human blood and plateletpheresis residues were compared for their content of hemopoietic precursor cells. Erythroid burst-forming units (BFU-E) averaged 560 +- 130 per ml of blood and granulocyte--monocyte colony forming units (CFU-C) averaged 240 +- 90 per ml blood. Estimates based on a blood volume of 7% of body weight indicate that the total blood pools of BFU-E and CFU-C are about 3.5 x 10/sup 6/ and 1.5 x 10/sup 6/ cells respectively. Sequential studies were performed over 3 days following one plateletpheresis in 4 donors. CFU-C and BFU-E approximately doubled between 48 and 72 hours after a plateletpheresis. During this time there was no significant alteration in the percent of null, T or B lymphocytes in blood. Thus, plateletpheresis appears to lead to a mobilization of precursor cells, which results in a transient increase in their concentration in blood. Therefore, pheresis 48 to 72 hours after an initial short-term procedure could harvest much larger numbers of precursor cells. Moreover, such techniques would put blood precursor cell content of plateletpheresis residues within reach of the precursor cell content in the volume of human marrow used for transplantation.

  19. T cell precursor migration towards beta 2-microglobulin is involved in thymus colonization of chicken embryos

    DEFF Research Database (Denmark)

    Dunon, D; Kaufman, J; Salomonsen, J

    1990-01-01

    beta 2-microglobulin (beta 2m) attracts hemopoietic precursors from chicken bone marrow cells in vitro. The cell population responding to beta 2m increases during the second period of thymus colonization, which takes place at days 12-14 of incubation. The precursors from 13.5 day old embryos were...... isolated after migration towards beta 2m in vitro and shown to be able to colonize a 13 day old thymus in ovo, where they subsequently acquire thymocyte markers. In contrast these beta 2m responsive precursors did not colonize embryonic bursa, i.e. differentiate into B lymphocytes. During chicken...... embryogenesis, peaks of beta 2m transcripts and of free beta 2m synthesis can only be detected in the thymus. The peak of free beta 2m synthesis in the thymus and the increase of beta 2m responding bone marrow cells both occur concomitantly with the second wave of thymus colonization in chicken embryo, facts...

  20. POOR HEMOPOIETIC STEM CELL MOBILIZERS IN MULTIPLE MYELOMA : A SINGLE INSTITUTION EXPERIENCE

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    Guillermo Jose Ruiz-Delgado

    2010-06-01

    Full Text Available In a single institution, in a group of 28 myeloma patients deemed eligible for autologous transplant, stem cell mobilization was attempted using filgrastim: 26 individuals were given 31 autografts employing 1-4 (median three apheresis sessions, to obtain a target stem cell dose of 1 x 106 CD34 viable cells / Kg of the recipient. The median number of grafted CD34 cells was 7.56 x 106  / Kg of the recipient; the range being 0.92 to 14.8.  By defining as poor mobilizers individuals in which a cell collection of 1 x 106 CD34 viable cells / Kg was better (80% at 80 months than those grafted with < 1 x 106 CD34 viable cells / Kg (67% at 76 months. Methods to improve stem cell mobilization are needed and may result in obtaining better results when autografting multiple myeloma patients.

  1. Donor Selection for Allogenic Hemopoietic Stem Cell Transplantation: Clinical and Ethical Considerations

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    Irene Riezzo

    2017-01-01

    Full Text Available Allogenic hematopoietic progenitor cell transplantation (allo-HSCT is an established treatment for many diseases. Stem cells may be obtained from different sources: mobilized peripheral blood stem cells, bone marrow, and umbilical cord blood. The progress in transplantation procedures, the establishment of experienced transplant centres, and the creation of unrelated adult donor registries and cord blood banks gave those without an human leucocyte antigen- (HLA- identical sibling donor the opportunity to find a donor and cord blood units worldwide. HSCT imposes operative cautions so that the entire donation/transplantation procedure is safe for both donors and recipients; it carries with it significant clinical, moral, and ethical concerns, mostly when donors are minors. The following points have been stressed: the donation should be excluded when excessive risks for the donor are reasonable, donors must receive an accurate information regarding eventual adverse events and health burden for the donors themselves, a valid consent is required, and the recipient’s risks must be outweighed by the expected benefits. The issue of conflict of interest, when the same physician has the responsibility for both donor selection and recipient care, is highlighted as well as the need of an adequate insurance protection for all the parties involved.

  2. Early B-lymphocyte precursor cells in mouse bone marrow: Subosteal localization of B220+ cells during postirradiation regeneration

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    Jacobsen, K.; Tepper, J.; Osmond, D.G. (McGill Univ., Montreal, Quebec (Canada))

    1990-05-01

    The localization of early B-lymphocyte precursor cells in the bone marrow of young mice has been studied during recovery from sublethal whole body gamma-irradiation (150 rad). Initial studies by double immunofluorescence labeling of the B-lineage-associated cell surface glycoprotein, B220, and of mu heavy chains in bone marrow cell suspensions, demonstrated a sequential wave of regeneration of early B precursor cells, pre-B cells, and B cells. Early B precursor cells expressing B220 but not mu chains were enriched at 1-3 days following irradiation. After in vivo administration of 125I-labeled monoclonal antibody 14.8 to detect B220+ cells in situ, light and electron microscope radioautography of femoral bone marrow sections revealed concentrations of labeled B220+ cells located peripherally near the cortical bone at 1-3 days following irradiation, increasing in numbers in more central areas by 5-7 days. Proliferative B220+ precursor cells were found within layers of bone-lining cells and in a subosteal area characterized by a prominent electron-dense extracellular matrix, often associated with stromal reticular cells. The results demonstrate that the precursor cells that are active in the bone marrow early in the recovery of B lymphopoiesis after gamma-irradiation are located both within and near the endosteum of the surrounding bone. The distinctive extracellular matrix and stromal cell associations noted in this region may contribute to a supportive local microenvironment for early hemopoietic progenitor cells.

  3. The Innate Lymphoid Cell Precursor.

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    Ishizuka, Isabel E; Constantinides, Michael G; Gudjonson, Herman; Bendelac, Albert

    2016-05-20

    The discovery of tissue-resident innate lymphoid cell populations effecting different forms of type 1, 2, and 3 immunity; tissue repair; and immune regulation has transformed our understanding of mucosal immunity and allergy. The emerging complexity of these populations along with compounding issues of redundancy and plasticity raise intriguing questions about their precise lineage relationship. Here we review advances in mapping the emergence of these lineages from early lymphoid precursors. We discuss the identification of a common innate lymphoid cell precursor characterized by transient expression of the transcription factor PLZF, and the lineage relationships of innate lymphoid cells with conventional natural killer cells and lymphoid tissue inducer cells. We also review the rapidly growing understanding of the network of transcription factors that direct the development of these lineages.

  4. Mechanisms of lymphocytic choriomeningitis virus-induced hemopoietic dysfunction

    DEFF Research Database (Denmark)

    Thomsen, Allan Randrup; Pisa, P; Bro-Jørgensen, K

    1986-01-01

    Results of this study showed that lymphocytic choriomeningitis virus infection causes a marked activation of natural killer (NK) cells not only in the spleen but also in the bone marrow. This activity reached its peak at about day 3 of infection and declined after days 6 to 7. Enhanced NK cell...... the receptivity for syngeneic hemopoietic cells. These findings are consistent with the hypothesis that NK cell activation causes rejection of syngeneic stem cells, thus resulting in hemopoietic depression. To understand the mechanisms behind the prolonged decrease in bone marrow receptivity (and bone marrow....... It seems, therefore, that as NK cell activity declines, the spleen regains the ability to support growth of hemopoietic cells and the bone marrow resumes an elevated export of stem cells to the spleen. This diversion of hemopoiesis could explain both the long-standing deficiencies of the bone marrow...

  5. Bone Marrow Graft-Versus-Host Disease in Major Histocompatibility Complex-Matched Murine Reduced-Intensity Allogeneic Hemopoietic Cell Transplantation.

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    Shahin, Kifah; Mattar, Zamil; Silveira, Pablo; Hsu, Wei-Hsun; Bendall, Linda; Hart, Derek; Bradstock, Kenneth F

    2017-11-01

    Most clinical allogeneic hemopoietic cell transplants (alloHCT) are now performed using reduced-intensity conditioning (RIC) instead of myeloablative conditioning (MAC); however, the biology underlying this treatment remains incompletely understood. We investigated a murine model of major histocompatibility complex-matched multiple minor histocompatibility antigen-mismatched alloHCT using bone marrow (BM) cells and splenocytes from B6 (H-2) donor mice transplanted into BALB.B (H-2) recipients after RIC with fludarabine of 100 mg/kg per day for 5 days, cyclophosphamide of 60 mg/kg per day for 2 days, and total body irradiation (TBI). The lowest TBI dose capable of achieving complete donor chimerism in this mouse strain combination was 325 cGy given as a single fraction. Mice that underwent RIC had a reduced incidence and delayed onset of graft-versus-host disease (GVHD) and significantly prolonged survival compared with MAC-transplanted recipients (TBI of 850 cGy plus cyclophosphamide of 60 mg/kg per day for 2 days). Compared with syngeneic controls, RIC mice with GVHD showed evidence of BM suppression, have anemia, reduced BM cellularity, and showed profound reduction in BM B cell lymphopoiesis associated with damage to the endosteal BM niche. This was associated with an increase in BM CD8 effector T cells in RIC mice and elevated blood and BM plasma levels of T helper1 cytokines. Increasing doses of splenocytes resulted in increased incidence of GVHD in RIC mice. We demonstrate that the BM is a major target organ of GVHD in an informative clinically relevant RIC mouse major histocompatibility complex-matched alloHCT model by a process that seems to be driven by CD8 effector T cells.

  6. Hemopoietic progenitor cell identification in fetal and adult blood Célula progenitora hamatopoética - identificação em sangue fetal e de adulto

    Directory of Open Access Journals (Sweden)

    Aixa Müller

    2008-06-01

    Full Text Available Hemopoietic progenitor cells give rise to all cellular elements of the blood and are of importance as a potential source of cells used for correction of various pathological conditions. The main objective of this study was to identify and quantitative hemopoietic progenitor cell in antenatal fetal blood, in cord blood at the time of delivery and in adult blood, using monoclonal antibodies to surface markers and flow cytometry. CD34+ cells, most of them probably representing progenitor cells, were detected in prenatal fetal blood as early as the 17th week of gestation. The proportion of these cells showed a tendency to decrease as the pregnancy progressed. Within the population of CD34+ cells, a relatively low proportion (less than 1% were negative for the surface marker CD33 or HLA-Dr, indicating a population of primitive stem cells, i.e., progenitor cells no committed to a specific lineage. On the contrary, another group coexpressed CD33 or HLA-Dr, being more mature progenitor cells already committed to differentiate along a specific lineage. The percentage of CD34+ obtained in blood of adult patients after mobilization with chemotherapeutic agents and growth factors showed an average value of 2.7± 3.1%. The percentage of CD34+ in the apheresis products of various patients varied from 0.58 to 1.48. In some cases the cells were reinfused in the patient with good results. Our findings are in agreement with previous studies suggesting that CD34+ stem cells is a heterogeneous population, with each subset having variable degree o commitment to differentiate toward a specific cell lineage.As células progenitoras hematopoéticas são as responsáveis pela produção de todos os elementos do sangue e são as potenciais fontes de células usadas para o tratamento de várias condições patológicas. O principal objetivo deste trabalho foi identificar e quantificar as células progenitoras hematopoiéticas no sangue fetal do período pré-natal, no

  7. Cell-specific precursor processing

    DEFF Research Database (Denmark)

    Rehfeld, Jens F; Bundgaard, Jens R

    2010-01-01

    in different cells and tissues therefore requires control of biogenesis and secretion in order to avoid interference with the function of a specific hormonal peptide from a particular endocrine cell. Several mechanisms are involved in such control, one of them being cell-specific processing of prohormones....... The following pages present four examples of such cell-specific processing and the implications of the phenomenon for the use of peptide hormones as markers of diseases. Notably, sick cells - not least the neoplastic cells - often process prohormones in a manner different from that of the normal endocrine cells....

  8. Hemopoietic cell kinase (Hck) and p21-activated kinase 2 (PAK2) are involved in the down-regulation of CD1a lipid antigen presentation by HIV-1 Nef in dendritic cells.

    Science.gov (United States)

    Shinya, Eiji; Shimizu, Masumi; Owaki, Atsuko; Paoletti, Samantha; Mori, Lucia; De Libero, Gennaro; Takahashi, Hidemi

    2016-01-01

    Dendritic cells (DCs) play a major role in in vivo pathogenesis of HIV-1 infection. Therefore, DCs may provide a promising strategy to control and eventually overcome the fatal infection. Especially, immature DCs express all CD1s, the non-MHC lipid antigen -presenting molecules, and HIV-1 Nef down-regulates CD1 expression besides MHC. Moreover, CD1d-restricted CD4(+) NKT cells are infected by HIV-1, reducing the number of these cells in HIV-1-infected individuals. To understand the exact role of DCs and CD1-mediated immune response during HIV-1 infection, Nef down-regulation of CD1a-restricted lipid/glycolipid Ag presentation in iDCs was analyzed. We demonstrated the involvement of the association of Nef with hemopoietic cell kinase (Hck) and p21-activated kinase 2 (PAK2), and that Hck, which is expressed strongly in iDCs, augmented this mutual interaction. Hck might be another therapeutic target to preserve the function of HIV-1 infected DCs, which are potential reservoirs of HIV-1 even after antiretroviral therapy. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Cytomegalovirus-specific cytotoxic T lymphocytes can be efficiently expanded from granulocyte colony-stimulating factor-mobilized hemopoietic progenitor cell products ex vivo and safely transferred to stem cell transplantation recipients to facilitate immune reconstitution.

    Science.gov (United States)

    Clancy, Leighton E; Blyth, Emily; Simms, Renee M; Micklethwaite, Kenneth P; Ma, Chun-Kei K; Burgess, Jane S; Antonenas, Vicki; Shaw, Peter J; Gottlieb, David J

    2013-05-01

    Uncontrolled cytomegalovirus (CMV) reactivation after allogeneic hematopoietic stem cell transplantation causes significant morbidity and mortality. Adoptive transfer of CMV-specific cytotoxic T lymphocytes (CTLs) is a promising therapy to treat reactivation and prevent viral disease. In this article, we describe the generation of clinical-grade CMV-specific CTLs directly from granulocyte colony-stimulating factor-mobilized hemopoietic progenitor cell (G-HPC) products collected for transplantation. This method requires less than 2.5% of a typical G-HPC product to reproducibly expand CMV-specific CTLs ex vivo. Comparison of 11 CMV CTL lines generated from G-HPC products with 52 CMV CTL lines generated from nonmobilized peripheral blood revealed similar expansion kinetics and phenotype. G-HPC-derived CTLs produced IFN-γ after reexposure to CMVpp65 antigen and exhibited CMV-directed cytotoxicity but no alloreactivity against transplantation recipient-derived cells. Seven patients received CMV-specific CTL lines expanded from G-HPC products in a prophylactic adoptive immunotherapy phase I/II clinical trial. Use of G-HPC products will facilitate integration of CTL generation into established quality systems of transplantation centers and more rapid inclusion of T cell therapies into routine clinical care. Copyright © 2013 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

  10. Mechanisms of napelline action stimulating the regeneration of hemopoietic tissue in cytostatic myelosuppression.

    Science.gov (United States)

    Zyuz'kov, G N; Zhdanov, V V; Udut, E V; Miroshnichenko, L A; Losev, E A; Simanina, E V; Chaikovskiy, A V; Suslov, N I; Povet'eva, T N; Krapivin, A V; Nesterova, Yu V; Agafonov, V I; Minakova, M Yu; Stavrova, L A; Danilets, M G; Ligacheva, A A; Trofimova, E S; Ivanova, A N; Goldberg, V E; Reikchart, D V; Dygai, A M

    2013-08-01

    Pronounced regenerative effects of alkaloid napelline extracted from Aconitum baicalense on granulocytic hemopoiesis were revealed in the model of cytostatic myelosuppression. Activation of functions of hemopoietic progenitor cells along with increased feeder capacity of the stromal elements in the hemopoiesis inducing microenvironment with decreased levels mesenchymal progenitor cells in the bone marrow are the mechanisms underlying the hemostimulating action of this substance.

  11. Heterogeneity of the radiosensitivity and origins of tissue macrophage colony-forming cells

    Energy Technology Data Exchange (ETDEWEB)

    Oghiso, Yoichi; Yamada, Yutaka (National Inst. of Radiological Sciences, Chiba (Japan))

    1992-12-01

    Previous studies suggest that the radiosensitivity and origin of tissue macrophage precursors differ from those of hemopoietic macrophage colony-forming units (CFU-Ms) committed to macrophage-lineage cells. We assessed the origins of tissue macrophage colony-forming cells (M-CFCs) in mice by comparing their kinetics and radiosensitivities in the normal steady state and under the conditions of bone marrow depletion by [sup 89]Sr-administration and/or splenectomy. The results indicate that the radiosensitive peritoneal M-CFCs elicited by thioglycollate are derived from bone marrow macrophage precursors; where as alveolar M-CFCs, which are radioresistant, are self-sustained locally and independent of hemopoietic macrophage precursors. In contrast, highly radiosensitive liver M-CFCs are probably derived from CFU-Ms that appear to be propagated in the spleen in association with hemopoietic responses. (author).

  12. Innate lymphoid cells, precursors and plasticity.

    Science.gov (United States)

    Gronke, Konrad; Kofoed-Nielsen, Michael; Diefenbach, Andreas

    2016-11-01

    Innate lymphoid cells (ILC) have only recently been recognized as a separate entity of the lymphoid lineage. Their subpopulations share common characteristics in terms of early development and major transcriptional circuitry with their related cousins of the T cell world. It is currently hypothesized that ILCs constitute an evolutionary older version of the lymphoid immune system. They are found at all primary entry points for pathogens such as mucosal surfaces of the lung and gastrointestinal system, the skin and the liver, which is the central contact point for pathogens that breach the intestinal barrier and enter the circulation. There, ILC contribute to the first line defense as well as to organ homeostasis. However, ILC are not only involved in classical defense tasks, but also contribute to the organogenesis of lymphoid organs as well as tissue remodeling and even stem cell regeneration. ILC may, therefore, implement different functions according to their emergence in ontogeny, their development and their final tissue location. We will review here their early development from precursors of the fetal liver and the adult bone marrow as well as their late plasticity in adaptation to their environment. Copyright © 2016 European Federation of Immunological Societies. Published by Elsevier B.V. All rights reserved.

  13. Conditions for the differentiation of melanocyte-precursor cells from ...

    African Journals Online (AJOL)

    Conditions for the differentiation of melanocyte-precursor cells from human cord blood-derived mesenchymal stem cells. Jienny Lee, Jongsung Lee, Kyungbaeg Roh, Myeong-Ok Kim, Ju-Duck Kim, Deokhoon Park ...

  14. Cryopreservation of GABAergic Neuronal Precursors for Cell-Based Therapy.

    Directory of Open Access Journals (Sweden)

    Daniel Rodríguez-Martínez

    Full Text Available Cryopreservation protocols are essential for stem cells storage in order to apply them in the clinic. Here we describe a new standardized cryopreservation protocol for GABAergic neural precursors derived from the medial glanglionic eminence (MGE, a promising source of GABAergic neuronal progenitors for cell therapy against interneuron-related pathologies. We used 10% Me2SO as cryoprotectant and assessed the effects of cell culture amplification and cellular organization, as in toto explants, neurospheres, or individualized cells, on post-thaw cell viability and retrieval. We confirmed that in toto cryopreservation of MGE explants is an optimal preservation system to keep intact the interneuron precursor properties for cell transplantation, together with a high cell viability (>80% and yield (>70%. Post-thaw proliferation and self-renewal of the cryopreserved precursors were tested in vitro. In addition, their migration capacity, acquisition of mature neuronal morphology, and potency to differentiate into multiple interneuron subtypes were also confirmed in vivo after transplantation. The results show that the cryopreserved precursor features remained intact and were similar to those immediately transplanted after their dissection from the MGE. We hope this protocol will facilitate the generation of biobanks to obtain a permanent and reliable source of GABAergic precursors for clinical application in cell-based therapies against interneuronopathies.

  15. Cryopreservation of GABAergic Neuronal Precursors for Cell-Based Therapy

    Science.gov (United States)

    2017-01-01

    Cryopreservation protocols are essential for stem cells storage in order to apply them in the clinic. Here we describe a new standardized cryopreservation protocol for GABAergic neural precursors derived from the medial glanglionic eminence (MGE), a promising source of GABAergic neuronal progenitors for cell therapy against interneuron-related pathologies. We used 10% Me2SO as cryoprotectant and assessed the effects of cell culture amplification and cellular organization, as in toto explants, neurospheres, or individualized cells, on post-thaw cell viability and retrieval. We confirmed that in toto cryopreservation of MGE explants is an optimal preservation system to keep intact the interneuron precursor properties for cell transplantation, together with a high cell viability (>80%) and yield (>70%). Post-thaw proliferation and self-renewal of the cryopreserved precursors were tested in vitro. In addition, their migration capacity, acquisition of mature neuronal morphology, and potency to differentiate into multiple interneuron subtypes were also confirmed in vivo after transplantation. The results show that the cryopreserved precursor features remained intact and were similar to those immediately transplanted after their dissection from the MGE. We hope this protocol will facilitate the generation of biobanks to obtain a permanent and reliable source of GABAergic precursors for clinical application in cell-based therapies against interneuronopathies. PMID:28122047

  16. Laser microdissection of sensory organ precursor cells of Drosophila microchaetes.

    Directory of Open Access Journals (Sweden)

    Eulalie Buffin

    Full Text Available BACKGROUND: In Drosophila, each external sensory organ originates from the division of a unique precursor cell (the sensory organ precursor cell or SOP. Each SOP is specified from a cluster of equivalent cells, called a proneural cluster, all of them competent to become SOP. Although, it is well known how SOP cells are selected from proneural clusters, little is known about the downstream genes that are regulated during SOP fate specification. METHODOLOGY/PRINCIPAL FINDINGS: In order to better understand the mechanism involved in the specification of these precursor cells, we combined laser microdissection, toisolate SOP cells, with transcriptome analysis, to study their RNA profile. Using this procedure, we found that genes that exhibit a 2-fold or greater expression in SOPs versus epithelial cells were mainly associated with Gene Ontology (GO terms related with cell fate determination and sensory organ specification. Furthermore, we found that several genes such as pebbled/hindsight, scabrous, miranda, senseless, or cut, known to be expressed in SOP cells by independent procedures, are particularly detected in laser microdissected SOP cells rather than in epithelial cells. CONCLUSIONS/SIGNIFICANCE: These results confirm the feasibility and the specificity of our laser microdissection based procedure. We anticipate that this analysis will give new insight into the selection and specification of neural precursor cells.

  17. Isolation of Oct4-expressing extraembryonic endoderm precursor cell lines.

    Directory of Open Access Journals (Sweden)

    Bisrat G Debeb

    Full Text Available BACKGROUND: The extraembryonic endoderm (ExEn defines the yolk sac, a set of membranes that provide essential support for mammalian embryos. Recent findings suggest that the committed ExEn precursor is present already in the embryonic Inner Cell Mass (ICM as a group of cells that intermingles with the closely related epiblast precursor. All ICM cells contain Oct4, a key transcription factor that is first expressed at the morula stage. In vitro, the epiblast precursor is most closely represented by the well-characterized embryonic stem (ES cell lines that maintain the expression of Oct4, but analogous ExEn precursor cell lines are not known and it is unclear if they would express Oct4. METHODOLOGY/PRINCIPAL FINDINGS: Here we report the isolation and characterization of permanently proliferating Oct4-expressing rat cell lines ("XEN-P cell lines", which closely resemble the ExEn precursor. We isolated the XEN-P cell lines from blastocysts and characterized them by plating and gene expression assays as well as by injection into embryos. Like ES cells, the XEN-P cells express Oct4 and SSEA1 at high levels and their growth is stimulated by leukemia inhibitory factor, but instead of the epiblast determinant Nanog, they express the ExEn determinants Gata6 and Gata4. Further, they lack markers characteristic of the more differentiated primitive/visceral and parietal ExEn stages, but exclusively differentiate into these stages in vitro and contribute to them in vivo. CONCLUSIONS/SIGNIFICANCE: Our findings (i suggest strongly that the ExEn precursor is a self-renewable entity, (ii indicate that active Oct4 gene expression (transcription plus translation is part of its molecular identity, and (iii provide an in vitro model of early ExEn differentiation.

  18. Culture of Mouse Neural Stem Cell Precursors

    OpenAIRE

    Currle, D. Spencer; Hu, Jia Sheng; Kolski-Andreaco, Aaron; Monuki, Edwin S.

    2007-01-01

    Primary neural stem cell cultures are useful for studying the mechanisms underlying central nervous system development. Stem cell research will increase our understanding of the nervous system and may allow us to develop treatments for currently incurable brain diseases and injuries. In addition, stem cells should be used for stem cell research aimed at the detailed study of mechanisms of neural differentiation and transdifferentiation and the genetic and environmental signals that direct the...

  19. Differentiation of Mouse Embryonic Stem Cells into Ventral Foregut Precursors

    DEFF Research Database (Denmark)

    Rothová, Michaela; Hölzenspies, Jurriaan J; Livigni, Alessandra

    2016-01-01

    Anterior definitive endoderm (ADE), the ventral foregut precursor, is both an important embryonic signaling center and a unique multipotent precursor of liver, pancreas, and other organs. Here, a method is described for the differentiation of mouse embryonic stem cells (mESCs) to definitive...... endoderm with pronounced anterior character. ADE-containing cultures can be produced in vitro by suspension (embryoid body) culture or in a serum-free adherent monolayer culture. ESC-derived ADE cells are committed to endodermal fates and can undergo further differentiation in vitro towards ventral foregut...

  20. Oligodendrocyte precursor cells synthesize neuromodulatory factors.

    Directory of Open Access Journals (Sweden)

    Dominik Sakry

    Full Text Available NG2 protein-expressing oligodendrocyte progenitor cells (OPC are a persisting and major glial cell population in the adult mammalian brain. Direct synaptic innervation of OPC by neurons throughout the brain together with their ability to sense neuronal network activity raises the question of additional physiological roles of OPC, supplementary to generating myelinating oligodendrocytes. In this study we investigated whether OPC express neuromodulatory factors, typically synthesized by other CNS cell types. Our results show that OPC express two well-characterized neuromodulatory proteins: Prostaglandin D2 synthase (PTGDS and neuronal Pentraxin 2 (Nptx2/Narp. Expression levels of the enzyme PTGDS are influenced in cultured OPC by the NG2 intracellular region which can be released by cleavage and localizes to glial nuclei upon transfection. Furthermore PTGDS mRNA levels are reduced in OPC from NG2-KO mouse brain compared to WT cells after isolation by cell sorting and direct analysis. These results show that OPC can contribute to the expression of these proteins within the CNS and suggest PTGDS expression as a downstream target of NG2 signaling.

  1. Whole-cell fungal transformation of precursors into dyes

    Directory of Open Access Journals (Sweden)

    Jarosz-Wilkołazka Anna

    2010-07-01

    Full Text Available Abstract Background Chemical methods of producing dyes involve extreme temperatures and unsafe toxic compounds. Application of oxidizing enzymes obtained from fungal species, for example laccase, is an alternative to chemical synthesis of dyes. Laccase can be replaced by fungal biomass acting as a whole-cell biocatalyst with properties comparable to the isolated form of the enzyme. The application of the whole-cell system simplifies the transformation process and reduces the time required for its completion. In the present work, four fungal strains with a well-known ability to produce laccase were tested for oxidation of 17 phenolic and non-phenolic precursors into stable and non-toxic dyes. Results An agar-plate screening test of the organic precursors was carried out using four fungal strains: Trametes versicolor, Fomes fomentarius, Abortiporus biennis, and Cerrena unicolor. Out of 17 precursors, nine were transformed into coloured substances in the presence of actively growing fungal mycelium. The immobilized fungal biomass catalyzed the transformation of 1 mM benzene and naphthalene derivatives in liquid cultures yielding stable and non-toxic products with good dyeing properties. The type of fungal strain had a large influence on the absorbance of the coloured products obtained after 48-hour transformation of the selected precursors, and the most effective was Fomes fomentarius (FF25. Whole-cell transformation of AHBS (3-amino-4-hydroxybenzenesulfonic acid into a phenoxazinone dye was carried out in four different systems: in aqueous media comprising low amounts of carbon and nitrogen source, in buffer, and in distilled water. Conclusions This study demonstrated the ability of four fungal strains belonging to the ecological type of white rot fungi to transform precursors into dyes. This paper highlights the potential of fungal biomass for replacing isolated enzymes as a cheaper industrial-grade biocatalyst for the synthesis of dyes and other

  2. Thin film solar cells by selenization sulfurization using diethyl selenium as a selenium precursor

    Science.gov (United States)

    Dhere, Neelkanth G.; Kadam, Ankur A.

    2009-12-15

    A method of forming a CIGSS absorber layer includes the steps of providing a metal precursor, and selenizing the metal precursor using diethyl selenium to form a selenized metal precursor layer (CIGSS absorber layer). A high efficiency solar cell includes a CIGSS absorber layer formed by a process including selenizing a metal precursor using diethyl selenium to form the CIGSS absorber layer.

  3. Protective Effects of Squid Ink Extract Towards Hemopoietic Injuries Induced by Cyclophosphamine

    Science.gov (United States)

    Zhong, Jie-Ping; Wang, Guang; Shang, Jiang-Hua; Pan, Jiang-Qiu; Li, Kun; Huang, Yan; Liu, Hua-Zhong

    2009-01-01

    To investigate the protective effects of squid ink in chemotherapy, BALB/c mice were used as animal models of injuries induced by cyclophosphamine, a well known chemotherapeutic drug. The mice were randomly divided into five groups with the same number of males and females in each group. At the end of the experiment, animals were sacrificed to investigate organ indexes and antioxidant ability of the spleen, peripheral blood profile and quantities of bone marrow nucleated cells. Results showed that the hemopoietic function of mice was injured by cyclophosphamine, as indicated by decreases of contents of erythrocytes, leukocytes, hemoglobin and bone marrow nucleated cells (P0.05), as well as modification of organ indexes (Psepia extract markedly increased the levels of erythrocytes, leukocytes, hemoglobin and bone marrow nucleated cells (P0.05), and reversed the effects of cyclophosphamine on organ indexes and antioxidant ability of spleen (P<0.01 or P<0.05). In addition, squid ink extract did not change marrow hemopoiesis but improved the antioxidant ability of spleen in the animals. The data suggest that squid ink extract can protect the hemopoietic system from chemotherapeutic injury and could be employed to develop cell-protective drugs for use in clinical treatment of tumours. PMID:19370167

  4. Protective Effects of Squid Ink Extract Towards Hemopoietic Injuries Induced by Cyclophosphamine

    Directory of Open Access Journals (Sweden)

    Guang Wang

    2009-01-01

    Full Text Available To investigate the protective effects of squid ink in chemotherapy, BALB/c mice were used as animal models of injuries induced by cyclophosphamine, a well known chemotherapeutic drug. The mice were randomly divided into five groups with the same number of males and females in each group. At the end of the experiment, animals were sacrificed to investigate organ indexes and antioxidant ability of the spleen, peripheral blood profile and quantities of bone marrow nucleated cells. Results showed that the hemopoietic function of mice was injured by cyclophosphamine, as indicated by decreases of contents of erythrocytes, leukocytes, hemoglobin and bone marrow nucleated cells (P0.05, as well as modification of organ indexes (P0.05, and reversed the effects of cyclophosphamine on organ indexes and antioxidant ability of spleen (P<0.01 or P<0.05. In addition, squid ink extract did not change marrow hemopoiesis but improved the antioxidant ability of spleen in the animals. The data suggest that squid ink extract can protect the hemopoietic system from chemotherapeutic injury and could be employed to develop cell-protective drugs for use in clinical treatment of tumours.

  5. Proteomic analysis of osteogenic differentiation of dental follicle precursor cells

    DEFF Research Database (Denmark)

    Morsczeck, Christian; Petersen, Jørgen; Völlner, Florian

    2009-01-01

    Recently, there has been an increased interest in unravelling the molecular mechanisms and cellular pathways controlling the differentiation and proliferation of human stem cell lines. Proteome analysis has proven to be an effective approach to comprehensive analysis of the regulatory network...... of differentiation. In the present study we applied 2-DE combined with capillary-LC-MS/MS analysis to profile differentially regulated proteins upon differentiation of dental follicle precursor cells (DFPCs). Out of 115 differentially regulated proteins, glutamine synthetase, lysosomal proteinase cathepsin B....... The bioinformatic analyses suggest that proteins associated with cell cycle progression and protein metabolism were down-regulated and proteins involved in catabolism, cell motility and biological quality were up-regulated. These results display the general physiological state of DFPCs before and after osteogenic...

  6. Single Source Precursors for Thin Film Solar Cells

    Science.gov (United States)

    Banger, Kulbinder K.; Hollingsworth, Jennifer A.; Harris, Jerry D.; Cowen, Jonathan; Buhro, William E.; Hepp, Aloysius F.

    2002-01-01

    The development of thin film solar cells on flexible, lightweight, space-qualified substrates provides an attractive cost solution to fabricating solar arrays with high specific power, (W/kg). The use of a polycrystalline chalcopyrite absorber layer for thin film solar cells is considered as the next generation photovoltaic devices. At NASA GRC we have focused on the development of new single source precursors (SSP) and their utility to deposit the chalcopyrite semi-conducting layer (CIS) onto flexible substrates for solar cell fabrication. The syntheses and thermal modulation of SSPs via molecular engineering is described. Thin-film fabrication studies demonstrate the SSPs can be used in a spray CVD (chemical vapor deposition) process, for depositing CIS at reduced temperatures, which display good electrical properties, suitable for PV (photovoltaic) devices.

  7. Germ cell neoplasia in situ: The precursor cell for invasive germ cell tumors of the testis.

    Science.gov (United States)

    Spiller, Cassy M; Bowles, Josephine

    2017-05-01

    Germ cell neoplasia in situ is the non-invasive precursor cell of origin for type II testicular germ cell tumors. It has long been postulated that germ cell neoplasia in situ is derived from defective germ cell development during embryonic life, and although it is impossible to trace in vivo the progression from fetal germ cell to germ cell neoplasia in situ to tumor, there is a large volume of evidence supporting this theory. Current studies focus on understanding how germ cell neoplasia in situ forms, how these cells are activated at puberty and how they transform to invasive tumors of various subtypes. Such information is informing novel diagnostic and therapeutic options. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. A protocol for isolation and enriched monolayer cultivation of neural precursor cells from mouse dentate gyrus

    OpenAIRE

    Harish eBabu; Jan-Hendrik eClaasen; Jan-Hendrik eClaasen; Jan-Hendrik eClaasen; Suresh eKannan; Annette E. Rünker; Theo ePalmer; Gerd eKempermann; Gerd eKempermann

    2011-01-01

    In vitro assays are valuable tools to study the characteristics of adult neural precursor cells under controlled conditions with a defined set of parameters. We here present a detailed protocol based on our previous original publication (Babu et al., Enriched monolayer precursor cell cultures from micro-dissected adult mouse dentate gyrus yield functional granule cell-like neurons, PLoS One 2007, 2:e388) to isolate neural precursor cells from the hippocampus of adult mice and maintain and pro...

  9. Precursors of Executive Function in Infants With Sickle Cell Anemia

    Science.gov (United States)

    Hogan, Alexandra M.; Telfer, Paul T.; Kirkham, Fenella J.; de Haan, Michelle

    2013-01-01

    Executive dysfunction occurs in sickle cell anemia, but there are few early data. Infants with sickle cell anemia (n = 14) and controls (n = 14) performed the “A-not-B” and Object Retrieval search tasks, measuring precursors of executive function at 9 and 12 months. Significant group differences were not found. However, for the A-not-B task, 7 of 11 sickle cell anemia infants scored in the lower 2 performance categories at 9 months, but only 1 at 12 months (P = .024); controls obtained scores at 12 months that were statistically comparable to the scores they had already obtained at 9 months. On the Object Retrieval task, 9- and 12-month controls showed comparable scores, whereas infants with sickle cell anemia continued to improve (P = .027); at 9 months, those with lower hemoglobin oxygen saturation passed fewer trials (R s = 0.670, P = .024) and took longer to obtain the toy (R s = –0.664, P = .013). Subtle delays in acquiring developmental skills may underlie abnormal executive function in childhood. PMID:22859700

  10. Mouse ES cell-derived cardiac precursor cells are multipotent and facilitate identification of novel cardiac genes

    National Research Council Canada - National Science Library

    Christoforou, Nicolas; Miller, Ronald A; Hill, Christine M; Jie, Chunfa C; McCallion, Andrew S; Gearhart, John D

    2008-01-01

    Although the differentiation of ES cells to cardiomyocytes has been firmly established, the extent to which corresponding cardiac precursor cells can contribute to other cardiac populations remains unclear...

  11. A Protocol for Isolation and Enriched Monolayer Cultivation of Neural Precursor Cells from Mouse Dentate Gyrus

    OpenAIRE

    Babu, Harish; Claasen, Jan-Hendrik; Kannan, Suresh; Rünker, Annette E.; Palmer, Theo; Kempermann, Gerd

    2011-01-01

    In vitro assays are valuable tools to study the characteristics of adult neural precursor cells under controlled conditions with a defined set of parameters. We here present a detailed protocol based on our previous original publication (Babu et al., 2007) to isolate neural precursor cells from the hippocampus of adult mice and maintain and propagate them as adherent monolayer cultures. The strategy is based on the use of Percoll density gradient centrifugation to enrich precursor cells from ...

  12. Enrichment of skin-derived neural precursor cells from dermal cell populations by altering culture conditions.

    Science.gov (United States)

    Bayati, Vahid; Gazor, Rohoullah; Nejatbakhsh, Reza; Negad Dehbashi, Fereshteh

    2016-01-01

    As stem cells play a critical role in tissue repair, their manipulation for being applied in regenerative medicine is of great importance. Skin-derived precursors (SKPs) may be good candidates for use in cell-based therapy as the only neural stem cells which can be isolated from an accessible tissue, skin. Herein, we presented a simple protocol to enrich neural SKPs by monolayer adherent cultivation to prove the efficacy of this method. To enrich neural SKPs from dermal cell populations, we have found that a monolayer adherent cultivation helps to increase the numbers of neural precursor cells. Indeed, we have cultured dermal cells as monolayer under serum-supplemented (control) and serum-supplemented culture, followed by serum free cultivation (test) and compared. Finally, protein markers of SKPs were assessed and compared in both experimental groups and differentiation potential was evaluated in enriched culture. The cells of enriched culture concurrently expressed fibronectin, vimentin and nestin, an intermediate filament protein expressed in neural and skeletal muscle precursors as compared to control culture. In addition, they possessed a multipotential capacity to differentiate into neurogenic, glial, adipogenic, osteogenic and skeletal myogenic cell lineages. It was concluded that serum-free adherent culture reinforced by growth factors have been shown to be effective on proliferation of skin-derived neural precursor cells (skin-NPCs) and drive their selective and rapid expansion.

  13. Alterations in hippocampal myelin and oligodendrocyte precursor cells during epileptogenesis.

    Science.gov (United States)

    Luo, Yuanyuan; Hu, Qiao; Zhang, Qian; Hong, Siqi; Tang, Xiaoju; Cheng, Li; Jiang, Li

    2015-11-19

    Recent reports have described damage to myelinated fibers in the central nervous system (CNS) in patients with temporal lobe epilepsy (TLE) and animal models. However, only limited data are available on the dynamic changes that occur in myelinated fibers, oligodendrocytes (which are myelin-forming cells), and oligodendrocyte precursor cells (OPCs), which are a reservoir of new oligodendrocytes, in the hippocampus throughout epileptogenesis. The current study was designed to examine this issue using a rat model of lithium-pilocarpine-induced epilepsy. Electroencephalography (EEG), immunofluorescence, and Western blot analysis showed that the loss of myelin and oligodendrocytes in the rat hippocampus began during the acute stage of epileptogenesis, and the severity of this loss increased throughout epileptogenesis. Accompanying this loss of myelin and oligodendrocytes, OPCs in the rat hippocampus became activated and their populations increased during several phases of epileptogenesis (the acute, latent and chronic phases). The transcription factors olig1 and olig2, which play crucial roles in regulating OPC proliferation, differentiation and remyelination, were up-regulated during the early phases (the acute and latent phases) followed by a sharp decline in their expression during the chronic and late chronic phases. This study is the first to confirm the loss of myelin and oligodendrocytes during lithium-pilocarpine-induced epileptogenesis accompanied by a transient increase in the number of OPCs. Prevention of the loss of myelin and oligodendrocytes may provide a novel treatment strategy for epilepsy. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. CD44-positive cells are candidates for astrocyte precursor cells in developing mouse cerebellum.

    Science.gov (United States)

    Cai, Na; Kurachi, Masashi; Shibasaki, Koji; Okano-Uchida, Takayuki; Ishizaki, Yasuki

    2012-03-01

    Neural stem cells are generally considered to be committed to becoming precursor cells before terminally differentiating into either neurons or glial cells during neural development. Neuronal and oligodendrocyte precursor cells have been identified in several areas in the murine central nervous system. The presence of astrocyte precursor cells (APCs) is not so well understood. The present study provides several lines of evidence that CD44-positive cells are APCs in the early postnatal mouse cerebellum. In developing mouse cerebellum, CD44-positive cells, mostly located in the white matter, were positive for the markers of the astrocyte lineage, but negative for the markers of mature astrocytes. CD44-positive cells were purified from postnatal cerebellum by fluorescence-activated cell sorting and characterized in vitro. In the absence of any signaling molecule, many cells died by apoptosis. The surviving cells gradually expressed glial fibrillary acidic protein, a marker for mature astrocytes, indicating that differentiation into mature astrocytes is the default program for these cells. The cells produced no neurospheres nor neurons nor oligodendrocytes under any condition examined, indicating these cells are not neural stem cells. Leukemia inhibitory factor greatly promoted astrocytic differentiation of CD44-positive cells, whereas bone morphogenetic protein 4 (BMP4) did not. Fibroblast growth factor-2 was a potent mitogen for these cells, but was insufficient for survival. BMP4 inhibited activation of caspase-3 and greatly promoted survival, suggesting a novel role for BMP4 in the control of development of astrocytes in cerebellum. We isolated and characterized only CD44 strongly positive large cells and discarded small and/or CD44 weakly positive cells in this study. Further studies are necessary to characterize these cells to help determine whether CD44 is a selective and specific marker for APCs in the developing mouse cerebellum. In conclusion, we succeeded in

  15. APPLICATION OF STEM CELLS AND PRECURSOR CELLS FOR STIMULATION OF ORGAN REVASCULARIZATION AND REGENERATION

    Directory of Open Access Journals (Sweden)

    M. V. Eremeeva

    2010-01-01

    Full Text Available Different angiogenic factors induced angiogenesis stimulation in ischemic tissues stays in the focus of scientific research for long time. The key role in ischemic angiogenesis belongs to endothelial precursor cells, plenty of which are reserved in bone marrow. Resident endothelial precursor cells are also found in some tissues and in circulation. These cells are involved in neoangiogenesis as well. Theoretically, injection of exogeneous endothelial precusor cells might contribute to restoration of circulation in the ischemic organ. Various types of cells have been approved for regeneration stimulation in a number of experimental protocols. A various degree of improvement of myocardial contractive function has been obtained as a universal result of these investigations, though the mechanisms underlying observed effect remain evasive. The paper focuses on advantages and drawbacks of embryonic, hematopoetic and mesenhimal stem cells application for angiogenesis stimulation and organs and tissues regeneration. 

  16. Mast cell repopulation of the peritoneal cavity: contribution of mast cell progenitors versus bone marrow derived committed mast cell precursors

    Directory of Open Access Journals (Sweden)

    Pastor Maria

    2010-06-01

    Full Text Available Abstract Background Mast cells have recently gained new importance as immunoregulatory cells that are involved in numerous pathological processes. One result of these processes is an increase in mast cell numbers at peripheral sites. This study was undertaken to determine the mast cell response in the peritoneal cavity and bone marrow during repopulation of the peritoneal cavity in rats. Results Two mast cell specific antibodies, mAb AA4 and mAb BGD6, were used to distinguish the committed mast cell precursor from more mature mast cells. The peritoneal cavity was depleted of mast cells using distilled water. Twelve hours after distilled water injection, very immature mast cells could be isolated from the blood and by 48 hours were present in the peritoneal cavity. At this same time the percentage of mast cells in mitosis increased fourfold. Mast cell depletion of the peritoneal cavity also reduced the total number of mast cells in the bone marrow, but increased the number of mast cell committed precursors. Conclusions In response to mast cell depletion of the peritoneal cavity, a mast cell progenitor is released into the circulation and participates in repopulation of the peritoneal cavity, while the committed mast cell precursor is retained in the bone marrow.

  17. Human iPSC-Derived GABA Ergic Precursor Cell Therapy for Chronic Epilepsy

    Science.gov (United States)

    2015-10-01

    AWARD NUMBER: W81XWH-14-1-0558 TITLE: Human iPSC-Derived GABA-Ergic Precursor Cell Therapy for Chronic Epilepsy PRINCIPAL INVESTIGATOR: Ashok K...AND SUBTITLE 5a. CONTRACT NUMBER Human iPSC-Derived GABA-Ergic Precursor Cell Therapy for Chronic Epilepsy 5b. GRANT NUMBER W81XWH-14-1-0558 5c...exhibiting chronic temporal lobe epilepsy (TLE) would: (1) greatly diminish the frequency and intensity of spontaneous recurrent seizures (SRS, Specific

  18. Direct Genesis of Functional Rodent and Human Schwann Cells from Skin Mesenchymal Precursors

    Directory of Open Access Journals (Sweden)

    Matthew P. Krause

    2014-07-01

    Full Text Available Recent reports of directed reprogramming have raised questions about the stability of cell lineages. Here, we have addressed this issue, focusing upon skin-derived precursors (SKPs, a dermally derived precursor cell. We show by lineage tracing that murine SKPs from dorsal skin originate from mesenchymal and not neural crest-derived cells. These mesenchymally derived SKPs can, without genetic manipulation, generate functional Schwann cells, a neural crest cell type, and are highly similar at the transcriptional level to Schwann cells isolated from the peripheral nerve. This is not a mouse-specific phenomenon, since human SKPs that are highly similar at the transcriptome level can be made from neural crest-derived facial and mesodermally derived foreskin dermis and the foreskin SKPs can make myelinating Schwann cells. Thus, nonneural crest-derived mesenchymal precursors can differentiate into bona fide peripheral glia in the absence of genetic manipulation, suggesting that developmentally defined lineage boundaries are more flexible than widely thought.

  19. Contribution of constitutively proliferating precursor cell subtypes to dentate neurogenesis after cortical infarcts

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    Oberland Julia

    2010-11-01

    Full Text Available Abstract Background It is well known that focal ischemia increases neurogenesis in the adult dentate gyrus of the hippocampal formation but the cellular mechanisms underlying this proliferative response are only poorly understood. We here investigated whether precursor cells which constitutively proliferate before the ischemic infarct contribute to post-ischemic neurogenesis. To this purpose, transgenic mice expressing green fluorescent protein (GFP under the control of the nestin promoter received repetitive injections of the proliferation marker bromodeoxyuridine (BrdU prior to induction of cortical infarcts. We then immunocytochemically analyzed the fate of these BrdU-positive precursor cell subtypes from day 4 to day 28 after the lesion. Results Quantification of BrdU-expressing precursor cell populations revealed no alteration in number of radial glia-like type 1 cells but a sequential increase of later precursor cell subtypes in lesioned animals (type 2a cells at day 7, type 3 cells/immature neurons at day 14. These alterations result in an enhanced survival of mature neurons 4 weeks postinfarct. Conclusions Focal cortical infarcts recruit dentate precursor cells generated already before the infarct and significantly contribute to an enhanced neurogenesis. Our findings thereby increase our understanding of the complex cellular mechanisms of postlesional neurogenesis.

  20. [Myeloid/natural killer cell precursor and myeloid/natural killer cell acute leukemia].

    Science.gov (United States)

    Ni, Ming; Chen, Bao-An

    2014-04-01

    With the popularity of flow cytometry, the classification of leukemia become more detailed. Myeloid/natural killer cell precursor acute leukemia and myeloid/natural killer cell acute leukemias are generally recognized as two kinds of rare leukemias and have poor prognosis. The cells expressed both myeloid and lymphatic antigens in these two leukemia and can not be diagnosed by morphology. The only basis to make a definite diagnosis is their unique Immunophenotyping. The role of CD7 and CD56 in these two leukemia are compelling, in the other hand, as the progress of cell differentiation research, there are many new awareness of NK cell differentiation. In this article, the biological origin, clinical manifestation, diagnosis, treatment and the role of CD7 and CD56 in these two leukemia are briefly summarized.

  1. Are Langhans giant cells precursors of foreign-body giant cells?

    Science.gov (United States)

    van der Rhee, H J; Hillebrands, W; Daems, W T

    1978-01-01

    Granulomas were induced in rats by subcutaneous implantation of pieces of Melinex plastic into the dorsum. The pieces of Melinex were removed at intervals varying from 16 h to 14 days, and the adherent cells were studied morphologically and quantitatively. Giant cell formation started about 32 h after implantation. The first giant cells to appear were of the Langhans type. Two days after implantation, most of the giant cells are still Langhans-type cells. A few giant cells of the foreign-body type and transition forms between the Langhans and foreign-body types are also present. From the third day on, the foreign-body type gradually becomes predominant. Independent of the duration of implantation, giant cells with 3, 4, or 5 nuclei are virtually without exception of the Langhans type. The higher the number of nuclei between 6 and 30, the more cells are of the foreign-body type. Giant cells with 30 or more nuclei are all foreign-body type. The findings are discussed in the light of current knowledge concerning giant cell formation. It is concluded that under the present experimental conditions, Langhans-type giant cells are the precursors of foreign-body-type giant cells.

  2. A protocol for isolation and enriched monolayer cultivation of neural precursor cells from mouse dentate gyrus

    Directory of Open Access Journals (Sweden)

    Harish eBabu

    2011-07-01

    Full Text Available In vitro assays are valuable tools to study the characteristics of adult neural precursor cells under controlled conditions with a defined set of parameters. We here present a detailed protocol based on our previous original publication (Babu et al., Enriched monolayer precursor cell cultures from micro-dissected adult mouse dentate gyrus yield functional granule cell-like neurons, PLoS One 2007, 2:e388 to isolate neural precursor cells from the hippocampus of adult mice and maintain and propagate them as adherent monolayer cultures. The strategy is based on the use of Percoll density gradient centrifugation to enrich precursor cells from the micro-dissected dentate gyrus. Based on the expression of Nestin and Sox2, a culture-purity of more than 98% can be achieved. The cultures are expanded under serum-free conditions in Neurobasal A medium with addition of the mitogens EGF and FGF2 as well as the supplements Glutamax-1 and B27. Under differentiation conditions, the precursor cells reliably generate approximately 30% neurons with appropriate morphological, molecular and electrophysiological characteristics that might reflect granule cell properties as their in vivo counterpart. We also highlight potential modifications to the protocol.

  3. Polysialic acid bioengineering of neuronal cells by N-acyl sialic acid precursor treatment.

    Science.gov (United States)

    Pon, Robert A; Biggs, Nancy J; Jennings, Harold J

    2007-03-01

    The inherent promiscuity of the polysialic acid (PSA) biosynthetic pathway has been exploited by the use of exogenous unnatural sialic acid precursor molecules to introduce unnatural modifications into cellular PSA, and has found applications in nervous system development and tumor vaccine studies. The sialic acid precursor molecules N-propionyl- and N-butanoyl-mannosamine (ManPr, ManBu) have been variably reported to affect PSA biosynthesis ranging from complete inhibition to de novo production of modified PSA, thus illustrating the need for further investigation into their effects. In this study, we have used a monoclonal antibody (mAb) 13D9, specific to both N-propionyl-PSA and N-butanoyl-PSA (NPrPSA and NBuPSA), together with flow cytometry, to study precursor-treated tumor cells and NT2 neurons at different stages of their maturation. We report that both ManPr and ManBu sialic acid precursors are metabolized and the resultant unnatural sialic acids are incorporated into de novo surface sialylglycoconjugates in murine and human tumor cells and, for the first time, in human NT2 neurons. Furthermore, neither precursor treatment deleteriously affected endogenous PSA expression; however, with NT2 cells, PSA levels were naturally downregulated as a function of their maturation into polarized neurons independent of sialic acid precursor treatment.

  4. Proximal visceral endoderm and extraembryonic ectoderm regulate the formation of primordial germ cell precursors

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    Hayashi Katsuhiko

    2007-12-01

    Full Text Available Abstract Background The extraembryonic tissues, visceral endoderm (VE and extraembryonic ectoderm (ExE are known to be important for the induction of primordial germ cells (PGCs in mice via activation of the bone morphogenetic protein (BMP signalling pathway. We investigated whether the VE and ExE have a direct role in the specification of PGCs, or in an earlier event, namely the induction of the PGC precursors in the proximal posterior epiblast cells. Results We cultured embryonic day (E 5.75 to E7.0 mouse embryos in an explant-assay with or without extraembryonic tissues. The reconstituted pieces of embryonic and extraembryonic tissues were assessed for the formation of both PGC precursors and specified PGCs. For this, Blimp1:gfp and Stella:gfp transgenic mouse lines were used to distinguish between PGC precursors and specified PGC, respectively. We observed that the VE regulates formation of an appropriate number of PGC precursors between E6.25–E7.25, but it is not essential for the subsequent specification of PGCs from the precursor cells. Furthermore, we show that the ExE has a different role from that of the VE, which is to restrict localization of PGC precursors to the posterior part of the embryo. Conclusion We show that the VE and ExE have distinct roles in the induction of PGC precursors, namely the formation of a normal number of PGC precursors, and their appropriate localization during early development. However, these tissues do not have a direct role during the final stages of specification of the founder population of PGCs.

  5. Transcription factor Runx1 is pro-neurogenic in adult hippocampal precursor cells.

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    Hirokazu Fukui

    Full Text Available Transcription factor Runx1 (Runt Related Transcription Factor 1, plays an important role in the differentiation of hematopoetic stem cells, angiogenesis and the development of nociceptive neurons. These known functions have in common that they relate to lineage decisions. We thus asked whether such role might also be found for Runx1 in adult hippocampal neurogenesis as a process, in which such decisions have to be regulated lifelong. Runx1 shows a widespread low expression in the adult mouse brain, not particularly prominent in the hippocampus and the resident neural precursor cells. Isoforms 1 and 2 of Runx1 (but not 3 to 5 driven by the proximal promoter were expressed in hippocampal precursor cells ex vivo, albeit again at very low levels, and were markedly increased after stimulation with TGF-β1. Under differentiation conditions (withdrawal of growth factors Runx1 became down-regulated. Overexpression of Runx1 in vitro reduced proliferation, increased survival of precursor cells by reducing apoptosis, and increased neuronal differentiation, while slightly reducing dendritic morphology and complexity. Transfection with dominant-negative Runx1 in hippocampal precursor cells in vitro did not result in differences in neurogenesis. Hippocampal expression of Runx1 correlated with adult neurogenesis (precursor cell proliferation across BXD recombinant strains of mice and covarying transcripts enriched in the GO categories "neural precursor cell proliferation" and "neuron differentiation". Runx1 is thus a plausible candidate gene to be involved in regulating initial differentiation-related steps of adult neurogenesis. It seems, however, that the relative contribution of Runx1 to such effect is complementary and will explain only small parts of the cell-autonomous pro-differentiation effect.

  6. In vitro generation of motor neuron precursors from mouse embryonic stem cells using mesoporous nanoparticles

    DEFF Research Database (Denmark)

    Garcia-Bennett, Alfonso E; König, Niclas; Abrahamsson, Ninnie

    2014-01-01

    Aim: Stem cell-derived motor neurons (MNs) are utilized to develop replacement strategies for spinal cord disorders. Differentiation of embryonic stem cells into MN precursors involves factors and their repeated administration. We investigated if delivery of factors loaded into mesoporous...

  7. B-cell precursor acute lymphoblastic leukemia and stromal cells communicate through Galectin-3

    Science.gov (United States)

    Fei, Fei; Joo, Eun Ji; Tarighat, Somayeh S.; Schiffer, Isabelle; Paz, Helicia; Fabbri, Muller; Abdel-Azim, Hisham; Groffen, John; Heisterkamp, Nora

    2015-01-01

    The molecular interactions between B-cell precursor acute lymphoblastic leukemia (pre-B ALL) cells and stromal cells in the bone marrow that provide microenvironmentally-mediated protection against therapeutic drugs are not well-defined. Galectin-3 (Lgals3) is a multifunctional galactose-binding lectin with reported location in the nucleus, cytoplasm and extracellular space in different cell types. We previously reported that ALL cells co-cultured with stroma contain high levels of Galectin-3. We here establish that, in contrast to more mature B-lineage cancers, Galectin-3 detected in and on the ALL cells originates from stromal cells, which express it on their surface, secrete it as soluble protein and also in exosomes. Soluble and stromal-bound Galectin-3 is internalized by ALL cells, transported to the nucleus and stimulates transcription of endogenous LGALS3 mRNA. When human and mouse ALL cells develop tolerance to different drugs while in contact with protective stromal cells, Galectin-3 protein levels are consistently increased. This correlates with induction of Galectin-3 transcription in the ALL cells. Thus Galectin-3 sourced from stroma becomes supplemented by endogenous Galectin-3 production in the pre-B ALL cells that are under continuous stress from drug treatment. Our data suggest that stromal Galectin-3 may protect ALL cells through auto-induction of Galectin-3 mRNA and tonic NFκB pathway activation. Since endogenously synthesized Galectin-3 protects pre-B ALL cells against drug treatment, we identify Galectin-3 as one possible target to counteract the protective effects of stroma. PMID:25869099

  8. Migratory appendicular muscles precursor cells in the common ancestor to all vertebrates.

    Science.gov (United States)

    Okamoto, Eri; Kusakabe, Rie; Kuraku, Shigehiro; Hyodo, Susumu; Robert-Moreno, Alexandre; Onimaru, Koh; Sharpe, James; Kuratani, Shigeru; Tanaka, Mikiko

    2017-11-01

    In amniote embryos, skeletal muscles in the trunk are derived from epithelial dermomyotomes, the ventral margin of which extends ventrally to form body wall muscles. At limb levels, ventral dermomyotomes also generate limb-muscle precursors, an Lbx1-positive cell population that originates from the dermomyotome and migrates distally into the limb bud. In elasmobranchs, however, muscles in the paired fins were believed to be formed by direct somitic extension, a developmental pattern used by the amniote body wall muscles. Here we re-examined the development of pectoral fin muscles in catsharks, Scyliorhinus, and found that chondrichthyan fin muscles are indeed formed from Lbx-positive muscle precursors. Furthermore, these precursors originate from the ventral edge of the dermomyotome, the rest of which extends towards the ventral midline to form body wall muscles. Therefore, the Lbx1-positive, de-epithelialized appendicular muscle precursors appear to have been established in the body plan before the divergence of Chondrichthyes and Osteichthyes.

  9. Schwann Cell Precursors from Human Pluripotent Stem Cells as a Potential Therapeutic Target for Myelin Repair

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    Han-Seop Kim

    2017-06-01

    Full Text Available Schwann cells play a crucial role in successful nerve repair and regeneration by supporting both axonal growth and myelination. However, the sources of human Schwann cells are limited both for studies of Schwann cell development and biology and for the development of treatments for Schwann cell-associated diseases. Here, we provide a rapid and scalable method to produce self-renewing Schwann cell precursors (SCPs from human pluripotent stem cells (hPSCs, using combined sequential treatment with inhibitors of the TGF-β and GSK-3 signaling pathways, and with neuregulin-1 for 18 days under chemically defined conditions. Within 1 week, hPSC-derived SCPs could be differentiated into immature Schwann cells that were functionally confirmed by their secretion of neurotrophic factors and their myelination capacity in vitro and in vivo. We propose that hPSC-derived SCPs are a promising, unlimited source of functional Schwann cells for treating demyelination disorders and injuries to the peripheral nervous system.

  10. Schwann Cell Precursors from Human Pluripotent Stem Cells as a Potential Therapeutic Target for Myelin Repair.

    Science.gov (United States)

    Kim, Han-Seop; Lee, Jungwoon; Lee, Da Yong; Kim, Young-Dae; Kim, Jae Yun; Lim, Hyung Jin; Lim, Sungmin; Cho, Yee Sook

    2017-06-06

    Schwann cells play a crucial role in successful nerve repair and regeneration by supporting both axonal growth and myelination. However, the sources of human Schwann cells are limited both for studies of Schwann cell development and biology and for the development of treatments for Schwann cell-associated diseases. Here, we provide a rapid and scalable method to produce self-renewing Schwann cell precursors (SCPs) from human pluripotent stem cells (hPSCs), using combined sequential treatment with inhibitors of the TGF-β and GSK-3 signaling pathways, and with neuregulin-1 for 18 days under chemically defined conditions. Within 1 week, hPSC-derived SCPs could be differentiated into immature Schwann cells that were functionally confirmed by their secretion of neurotrophic factors and their myelination capacity in vitro and in vivo. We propose that hPSC-derived SCPs are a promising, unlimited source of functional Schwann cells for treating demyelination disorders and injuries to the peripheral nervous system. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  11. precursor cells from human cord blood-derived mesenchymal stem ...

    African Journals Online (AJOL)

    ONOS

    2010-09-06

    Sep 6, 2010 ... The loss of skin pigmentation can induce compromised cutaneous immunity, which can result in conditions such as vitiligo. In this study, we evaluated various agents that are able to induce the differentiation of stem cells into melanocytes. We found that a mixture of forskolin (FK), stem cell factor. (SCF) and ...

  12. Allogeneic mesenchymal precursor cell therapy to limit remodeling after myocardial infarction: the effect of cell dosage.

    Science.gov (United States)

    Hamamoto, Hirotsugu; Gorman, Joseph H; Ryan, Liam P; Hinmon, Robin; Martens, Timothy P; Schuster, Michael D; Plappert, Theodore; Kiupel, Matti; St John-Sutton, Martin G; Itescu, Silviu; Gorman, Robert C

    2009-03-01

    This experiment assessed the dose-dependent effect of a unique allogeneic STRO-3-positive mesenchymal precursor cell (MPC) on postinfarction left ventricular (LV) remodeling. The MPCs were administered in a manner that would simulate an off-the-self, early postinfarction, preventative approach to cardiac cell therapy in a sheep transmural myocardial infarct (MI) model. Allogeneic MPCs were isolated from male crossbred sheep. Forty-six female sheep underwent coronary ligation to produce a transmural LV anteroapical infarction. One hour after infarction, the borderzone myocardium received an injection of 25, 75, 225, or 450 x 10(6) MPCs, or cell medium. Echocardiography was performed at 4 and 8 weeks after MI to quantify LV end-diastolic (LVEDV) and end-systolic volumes (LVESV), ejection fraction (EF), and infarct expansion. CD31 and smooth muscle actin (SMA) immunohistochemical staining was performed on infarct and borderzone specimens to quantify vascular density. Compared with controls, low-dose (25 and 75 x 10(6) cells) MPC treatment significantly attenuated infarct expansion and increases in LVEDV and LVESV. EF was improved at all cell doses. CD31 and SMA immunohistochemical staining demonstrated increased vascular density in the borderzone only at the lower cell doses. There was no evidence of myocardial regeneration within the infarct. Allogeneic STRO-3 positive MPCs attenuate the remodeling response to transmural MI in a clinically relevant large-animal model. This effect is associated with vasculogenesis and arteriogenesis within the borderzone and infarct and is most pronounced at lower cell doses.

  13. Hemopathologic predisposition and survival time under continuous gamma irradiation: responses mediated by altered radiosensitivity of hemopoietic progenitors

    Energy Technology Data Exchange (ETDEWEB)

    Seed, T.M.; Kaspar, L.V.; Tolle, D.V.; Fritz, T.E.

    1982-01-01

    These marked differences in radiosensitivity of individual animals within a relatively homogeneous, healthy pure bred group, as manifested by varying survival patterns and pathologic tendencies, have stimulated studies concerning the cellular bases of these responses. In previous studies, as in this one, the authors have attempted to characterize the cellular processes of hemopoietic recovery, an early occurring event characteristically observed in a select subgroup of MPD dogs exhibiting prolonged course of survival and a tendency to myeloproliferative disorders (MPD). Hemopoietic recovery appears to be a broadly based process as indicated by: (a) increased concentrations of blood granulocytes; (b) expanded granulocyte reserves; and (c) increased concentration of hemopoietic progenitors in the marrow. The intent of the present study was to examine the possibility that the cellular basis of hemopoietic recovery resides in the acquisition of increased radioresistance by hemopoietic progenitors, i.e., the suspected cellular targets of the hemopathic effects of ionizing irradiation.

  14. Characterization of Porcine Ventral Mesencephalic Precursor Cells following Long-Term Propagation in 3D Culture

    Directory of Open Access Journals (Sweden)

    Pia S. Jensen

    2012-01-01

    Full Text Available The potential use of predifferentiated neural precursor cells for treatment of a neurological disorder like Parkinson’s disease combines stem cell research with previous experimental and clinical transplantation of developing dopaminergic neurons. One current obstacle is, however, the lack of ability to generate dopaminergic neurons after long-term in vitro propagation of the cells. The domestic pig is considered a useful nonprimate large animal model in neuroscience, because of a better resemblance of the larger gyrencephalic pig brain to the human brain than the commonly used brains of smaller rodents. In the present study, porcine embryonic (28–30 days, ventral mesencephalic precursor cells were isolated and propagated as free-floating neural tissue spheres in medium containing epidermal growth factor and fibroblast growth factor 2. For passaging, the tissue spheres were cut into quarters, avoiding mechanical or enzymatic dissociation in order to minimize cellular trauma and preserve intercellular contacts. Spheres were propagated for up to 237 days with analysis of cellular content and differentiation at various time points. Our study provides the first demonstration that porcine ventral mesencephalic precursor cells can be long-term propagated as neural tissue spheres, thereby providing an experimental 3D in vitro model for studies of neural precursor cells, their niche, and differentiation capacity.

  15. Characterization of Porcine Ventral Mesencephalic Precursor Cells following Long-Term Propagation in 3D Culture

    Science.gov (United States)

    Jensen, Pia S.; Lyck, Lise; Jensen, Pia; Zimmer, Jens; Meyer, Morten

    2012-01-01

    The potential use of predifferentiated neural precursor cells for treatment of a neurological disorder like Parkinson's disease combines stem cell research with previous experimental and clinical transplantation of developing dopaminergic neurons. One current obstacle is, however, the lack of ability to generate dopaminergic neurons after long-term in vitro propagation of the cells. The domestic pig is considered a useful nonprimate large animal model in neuroscience, because of a better resemblance of the larger gyrencephalic pig brain to the human brain than the commonly used brains of smaller rodents. In the present study, porcine embryonic (28–30 days), ventral mesencephalic precursor cells were isolated and propagated as free-floating neural tissue spheres in medium containing epidermal growth factor and fibroblast growth factor 2. For passaging, the tissue spheres were cut into quarters, avoiding mechanical or enzymatic dissociation in order to minimize cellular trauma and preserve intercellular contacts. Spheres were propagated for up to 237 days with analysis of cellular content and differentiation at various time points. Our study provides the first demonstration that porcine ventral mesencephalic precursor cells can be long-term propagated as neural tissue spheres, thereby providing an experimental 3D in vitro model for studies of neural precursor cells, their niche, and differentiation capacity. PMID:23258982

  16. Export of Precursor tRNAIle from the Nucleus to the Cytoplasm in Human Cells.

    Directory of Open Access Journals (Sweden)

    Min Wei

    Full Text Available In the current concept, tRNA maturation in vertebrate cells, including splicing of introns, trimming of 5' leader and 3' trailer, and adding of CCA, is thought to occur exclusively in the nucleus. Here we provide evidence to challenge this concept. Unspliced intron-containing precursor tRNAIle was identified in Human Immunodeficiency Virus type 1 (HIV-1 virions, which are synthesized in the cytoplasm. Northern blot, confocal microscopy and quantitative RT-PCR further verified enrichment of this unspliced tRNAIle within the cytoplasm in human cells. In addition to containing an intron, the cytoplasmic precursor tRNAIle also contains a short incompletely processed 5´ leader and a 3´ trailer, which abundance is around 1000 fold higher than the nuclear precursor tRNAIle with long 5' leader and long 3' trailer. In vitro data also suggest that the cytoplasmic unspliced end-immature precursor tRNAIle could be processed by short isoform of RNase Z, but not long isoform of RNase Z. These data suggest that precursor tRNAs could export from the nucleus to the cytoplasm in human cells, instead of be processed only in the nucleus.

  17. Isolation of Precursor Cells from Waste Solid Fat Tissue

    Science.gov (United States)

    Byerly, Diane; Sognier, Marguerite A.

    2009-01-01

    A process for isolating tissue-specific progenitor cells exploits solid fat tissue obtained as waste from such elective surgical procedures as abdominoplasties (tummy tucks) and breast reductions. Until now, a painful and risky process of aspiration of bone marrow has been used to obtain a limited number of tissue- specific progenitor cells. The present process yields more tissue-specific progenitor cells and involves much less pain and risk for the patient. This process includes separation of fat from skin, mincing of the fat into small pieces, and forcing a fat saline mixture through a sieve. The mixture is then digested with collagenase type I in an incubator. After centrifugation tissue-specific progenitor cells are recovered and placed in a tissue-culture medium in flasks or Petri dishes. The tissue-specific progenitor cells can be used for such purposes as (1) generating three-dimensional tissue equivalent models for studying bone loss and muscle atrophy (among other deficiencies) and, ultimately, (2) generating replacements for tissues lost by the fat donor because of injury or disease.

  18. Nestin Reporter Transgene Labels Multiple Central Nervous System Precursor Cells

    Directory of Open Access Journals (Sweden)

    Avery S. Walker

    2010-01-01

    Full Text Available Embryonic neuroepithelia and adult subventricular zone (SVZ stem and progenitor cells express nestin. We characterized a transgenic line that expresses enhanced green fluorescent protein (eGFP specified to neural tissue by the second intronic enhancer of the nestin promoter that had several novel features. During embryogenesis, the dorsal telencephalon contained many and the ventral telencephalon few eGFP+ cells. eGFP+ cells were found in postnatal and adult neurogenic regions. eGFP+ cells in the SVZ expressed multiple phenotype markers, glial fibrillary acidic protein, Dlx, and neuroblast-specific molecules suggesting the transgene is expressed through the lineage. eGFP+ cell numbers increased in the SVZ after cortical injury, suggesting this line will be useful in probing postinjury neurogenesis. In non-neurogenic regions, eGFP was strongly expressed in oligodendrocyte progenitors, but not in astrocytes, even when they were reactive. This eGFP+ mouse will facilitate studies of proliferative neuroepithelia and adult neurogenesis, as well as of parenchymal oligodendrocytes.

  19. Coordinated regulation of niche and stem cell precursors by hormonal signaling.

    Directory of Open Access Journals (Sweden)

    Dana Gancz

    2011-11-01

    Full Text Available Stem cells and their niches constitute units that act cooperatively to achieve adult body homeostasis. How such units form and whether stem cell and niche precursors might be coordinated already during organogenesis are unknown. In fruit flies, primordial germ cells (PGCs, the precursors of germ line stem cells (GSCs, and somatic niche precursors develop within the larval ovary. Together they form the 16-20 GSC units of the adult ovary. We show that ecdysone receptors are required to coordinate the development of niche and GSC precursors. At early third instar, ecdysone receptors repress precocious differentiation of both niches and PGCs. Early repression is required for correct morphogenesis of the ovary and for protecting future GSCs from differentiation. At mid-third instar, ecdysone signaling is required for niche formation. Finally, and concurrent with the initiation of wandering behavior, ecdysone signaling initiates PGC differentiation by allowing the expression of the differentiation gene bag of marbles in PGCs that are not protected by the newly formed niches. All the ovarian functions of ecdysone receptors are mediated through early repression, and late activation, of the ecdysone target gene broad. These results show that, similar to mammals, a brain-gland-gonad axis controls the initiation of oogenesis in insects. They further exemplify how a physiological cue coordinates the formation of a stem cell unit within an organ: it is required for niche establishment and to ensure that precursor cells to adult stem cells remain undifferentiated until the niches can accommodate them. Similar principles might govern the formation of additional stem cell units during organogenesis.

  20. A protocol for isolation and enriched monolayer cultivation of neural precursor cells from mouse dentate gyrus.

    Science.gov (United States)

    Babu, Harish; Claasen, Jan-Hendrik; Kannan, Suresh; Rünker, Annette E; Palmer, Theo; Kempermann, Gerd

    2011-01-01

    In vitro assays are valuable tools to study the characteristics of adult neural precursor cells under controlled conditions with a defined set of parameters. We here present a detailed protocol based on our previous original publication (Babu et al., 2007) to isolate neural precursor cells from the hippocampus of adult mice and maintain and propagate them as adherent monolayer cultures. The strategy is based on the use of Percoll density gradient centrifugation to enrich precursor cells from the micro-dissected dentate gyrus. Based on the expression of Nestin and Sox2, a culture-purity of more than 98% can be achieved. The cultures are expanded under serum-free conditions in Neurobasal A medium with addition of the mitogens Epidermal growth factor and Fibroblast growth factor 2 as well as the supplements Glutamax-1 and B27. Under differentiation conditions, the precursor cells reliably generate approximately 30% neurons with appropriate morphological, molecular, and electrophysiological characteristics that might reflect granule cell properties as their in vivo counterpart. We also highlight potential modifications to the protocol.

  1. Sonic hedgehog-expressing basal cells are general post-mitotic precursors of functional taste receptor cells

    Science.gov (United States)

    Miura, Hirohito; Scott, Jennifer K.; Harada, Shuitsu; Barlow, Linda A.

    2014-01-01

    Background Taste buds contain ~60 elongate cells and several basal cells. Elongate cells comprise three functional taste cell types: I - glial cells, II - bitter/sweet/umami receptor cells, and III - sour detectors. Although taste cells are continuously renewed, lineage relationships among cell types are ill-defined. Basal cells have been proposed as taste bud stem cells, a subset of which express Sonic hedgehog (Shh). However, Shh+ basal cells turnover rapidly suggesting that Shh+ cells are precursors of some or all taste cell types. Results To fate map Shh-expressing cells, mice carrying ShhCreERT2 and a high (CAG-CAT-EGFP) or low (R26RLacZ) efficiency reporter allele were given tamoxifen to activate Cre in Shh+ cells. Using R26RLacZ, lineage-labeled cells occur singly within buds, supporting a post-mitotic state for Shh+ cells. Using either reporter, we show that Shh+ cells differentiate into all three taste cell types, in proportions reflecting cell type ratios in taste buds (I > II > III). Conclusions Shh+ cells are not stem cells, but are post-mitotic, immediate precursors of taste cells. Shh+ cells differentiate into each of the three taste cell types, and the choice of a specific taste cell fate is regulated to maintain the proper ratio within buds. PMID:24590958

  2. The union of somatic gonad precursors and primordial germ cells during C. elegans embryogenesis

    Science.gov (United States)

    Rohrschneider, Monica R.; Nance, Jeremy

    2013-01-01

    Somatic gonadal niche cells control the survival, differentiation, and proliferation of germline stem cells. The establishment of this niche-stem cell relationship is critical, and yet the precursors to these two cell types are often born at a distance from one another. The simple C. elegans gonadal primordium, which contains two somatic gonad precursors (SGPs) and two primordial germ cells (PGCs), provides an accessible model for determining how stem cell and niche cell precursors first assemble during development. To visualize the morphogenetic events that lead to formation of the gonadal primordium, we generated transgenic strains to label the cell membranes of the SGPs and PGCs and captured time-lapse movies as the gonadal primordium formed. We identify three distinct phases of SGP behavior: posterior migration along the endoderm towards the PGCs, extension of a single long projection around the adjacent PGC, and a dramatic wrapping over the PGC surfaces. We show that the endoderm and PGCs are dispensable for SGP posterior migration and initiation of projections. However, both tissues are required for the final positioning of the SGPs and the morphology of their projections, and PGCs are absolutely required for SGP wrapping behaviors. Finally, we demonstrate that the basement membrane component laminin, which localizes adjacent to the developing gonadal primordium, is required to prevent the SGPs from over-extending past the PGCs. Our findings provide a foundation for understanding the cellular and molecular regulation of the establishment of a niche-stem cell relationship. PMID:23562590

  3. Effects of retinoic acid signaling on extraocular muscle myogenic precursor cells in vitro.

    Science.gov (United States)

    Hebert, Sadie L; Fitzpatrick, Krysta R; McConnell, Samantha A; Cucak, Anja; Yuan, Ching; McLoon, Linda K

    2017-12-01

    One major difference between limb and extraocular muscles (EOM) is the presence of an enriched population of Pitx2-positive myogenic precursor cells in EOM compared to limb muscle. We hypothesize that retinoic acid regulates Pitx2 expression in EOM myogenic precursor cells and that its effects would differ in leg muscle. The two muscle groups expressed differential retinoic acid receptor (RAR) and retinoid X receptor (RXR) levels. RXR co-localized with the Pitx2-positive cells but not with those expressing Pax7. EOM-derived and LEG-derived EECD34 cells were treated with vehicle, retinoic acid, the RXR agonist bexarotene, the RAR inverse agonist BMS493, or the RXR antagonist UVI 3003. In vitro, fewer EOM-derived EECD34 cells expressed desmin and fused, while more LEG-derived cells expressed desmin and fused when treated with retinoic acid compared to vehicle. Both EOM and LEG-derived EECD34 cells exposed to retinoic acid showed a higher percentage of cells expressing Pitx2 compared to vehicle, supporting the hypothesis that retinoic acid plays a role in maintaining Pitx2 expression. We hypothesize that retinoic acid signaling aids in the maintenance of large numbers of undifferentiated myogenic precursor cells in the EOM, which would be required to maintain EOM normalcy throughout a lifetime of myonuclear turnover. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. N-acylethanolamines and precursor phospholipids - Relation to cell injury

    DEFF Research Database (Denmark)

    Hansen, Harald S.; Moesgaard, B.; Hansen, H.H.

    2000-01-01

    of mechanisms are proposed by which these two groups of lipids may have cytoprotective properties. The mechanisms may involve activation of cannabinoid receptors, as well as non-receptor-mediated effects such as stabilization of membrane bilayers, antioxidant mechanisms, inhibition of calcium leakage from......The present review focuses on the relationship between formation of N-acylethanolamine phospholipids (NAPEs) and N-acyletransferase (NAEs) catalyzed by N-acyltranferase and NAPE-hydrolyzing phospholipase D, respectively, and cell injury in tissues like brain, heart, and testis. A number...... mitochondria, and direct inhibition of ceramidase. Anandamide (20:4-NAE) is formed as a minor component along with other NAEs during cell injury. Whether 20:4-NAE has a separate physiological role is at present not known, but some data suggest that 20:4-NAE may be formed, e.g. in the uterus, by a more...

  5. IL-9-Producing Mast Cell Precursors and Food Allergy

    Science.gov (United States)

    2017-10-01

    MMC9s were induced in sensitized Fcer1a-/- mice, which consequently , exhibited less intestinal mastocytosis, produced fewer MCPt-1, and failed to...egg at only 4 months of age (6), suggesting that some patients with atopic dermatitis (AD) in early life may have a higher risk of developing food...University of Michigan, Department of Pathology , June 2017, Ann Arbor, MI 3. Emerging concepts of non-hematopoietic cell involvement in induction

  6. Effects of mood stabilizers on adult dentate gyrus-derived neural precursor cells.

    Science.gov (United States)

    Boku, Shuken; Nakagawa, Shin; Masuda, Takahiro; Nishikawa, Hiroyuki; Kato, Akiko; Toda, Hiroyuki; Song, Ning; Kitaichi, Yuji; Inoue, Takeshi; Koyama, Tsukasa

    2011-01-15

    Neurogenesis in the adult dentate gyrus (DG) is considered to be partly involved in the action of mood stabilizers. However, it remains unclear how mood stabilizers affect neural precursor cells in adult DG. We have established a culture system of adult rat DG-derived neural precursor cells (ADP) and have shown that lithium, a mood stabilizer, and dexamethasone, an agonist of glucocorticoid receptor, reciprocally regulate ADP proliferation. Neurogenesis constitutes not only proliferation of neural precursor cells but also apoptosis and differentiation. To develop further understanding of mood stabilizer effects on neural precursor cells in adult DG, we investigated and compared the effects of four common mood stabilizers-lithium, valproate, carbamazepine, and lamotrigine-on ADP proliferation, apoptosis, and differentiation. ADP proliferation, decreased by dexamethasone, was examined using Alamar Blue assay. Using TUNEL assay, ADP apoptosis induced by staurosporine was examined. The differentiated ADP induced by retinoic acid was characterized by immunostaining with anti-GFAP or anti-Tuj1 antibody. Lithium and valproate, but not carbamazepine and lamotrigine, recovered ADP proliferation decreased by dexamethasone. All four mood stabilizers decreased ADP apoptosis. Retinoic acid differentiated ADP into both neurons and astrocytes. Lithium and carbamazepine increased the ratio of neurons and decreased that of astrocytes. However, valproate and lamotrigine increased the ratio of astrocytes and decreased that of neurons. Therefore, these four stabilizers exhibited both common and differential effects on ADP proliferation, apoptosis, and differentiation. Copyright © 2010 Elsevier Inc. All rights reserved.

  7. Comparison of neurosphere-like cell clusters derived from dental follicle precursor cells and retinal Müller cells

    DEFF Research Database (Denmark)

    Beck, Hans Christian; Petersen, Jørgen; Felthaus, Oliver

    2011-01-01

    Unrelated cells such as dental follicle precursor cells (DFPCs) and retinal Müller cells (MCs) make spheres after cultivation in serum-replacement medium (SRM). Until today, the relation and molecular processes of sphere formation from different cell types remain undescribed. Thus in this study we...... or Alzheimer disease. Interestingly up-regulated proteins in DFPCs are involved in the biosynthesis of glycosphingolipids. These lipids are components of gangliosides such as GD3, which is a novel neural stem cell marker. In conclusion spheres from different types of cells have highly similar proteomes...... compared proteomes of spheres derived from MCs and DFPCs. 73% of 676 identified proteins were similar expressed in both cell types and many of them are expressed in the brain (55%). Moreover proteins are overrepresented that are associated with pathways for neural diseases such as Huntington disease...

  8. Primary orbital precursor T-cell lymphoblastic lymphoma

    DEFF Research Database (Denmark)

    Stenman, Lisa; Persson, Marta; Enlund, Fredrik

    2016-01-01

    Primary T-cell lymphoblastic lymphoma (T-LBL) in the eye region is very rare. The present study described a unique case of T-LBL involving the extraocular muscles. A 22-year-old male patient presented with a 3-week history of headache, reduced visual acuity and edema of the left eye. Clinical...... examination revealed left-sided exophthalmus, periorbital edema, chemosis, and reduced motility of the left eye. A magnetic resonance imaging scan revealed thickening of the left orbital muscles and a positron emission tomography-computed tomography scan also demonstrated activity in a subclavicular lymph...... genomic profile. The patient received chemotherapy according to the high-risk NOPHO protocol, followed by myeloablative allogenic bone marrow transplantation. At 35 months after diagnosis, the patient remained in complete first remission, but without light perception on his left eye. To the best of our...

  9. Meninges harbor cells expressing neural precursor markers during development and adulthood

    Science.gov (United States)

    Bifari, Francesco; Berton, Valeria; Pino, Annachiara; Kusalo, Marijana; Malpeli, Giorgio; Di Chio, Marzia; Bersan, Emanuela; Amato, Eliana; Scarpa, Aldo; Krampera, Mauro; Fumagalli, Guido; Decimo, Ilaria

    2015-01-01

    Brain and skull developments are tightly synchronized, allowing the cranial bones to dynamically adapt to the brain shape. At the brain-skull interface, meninges produce the trophic signals necessary for normal corticogenesis and bone development. Meninges harbor different cell populations, including cells forming the endosteum of the cranial vault. Recently, we and other groups have described the presence in meninges of a cell population endowed with neural differentiation potential in vitro and, after transplantation, in vivo. However, whether meninges may be a niche for neural progenitor cells during embryonic development and in adulthood remains to be determined. In this work we provide the first description of the distribution of neural precursor markers in rat meninges during development up to adulthood. We conclude that meninges share common properties with the classical neural stem cell niche, as they: (i) are a highly proliferating tissue; (ii) host cells expressing neural precursor markers such as nestin, vimentin, Sox2 and doublecortin; and (iii) are enriched in extracellular matrix components (e.g., fractones) known to bind and concentrate growth factors. This study underlines the importance of meninges as a potential niche for endogenous precursor cells during development and in adulthood. PMID:26483637

  10. Vitreous humor and albumin augment the proliferation of cultured retinal precursor cells

    DEFF Research Database (Denmark)

    Yang, Jing; Klassen, Henry; Pries, Mette

    2008-01-01

    Intravitreal injection is an important delivery route for studies involving the transplantation of various types of precursor cells to the retina; however, the effect on these cells of exposure to the vitreous microenvironment has not been specifically investigated. Here vitreous humor...... was evaluated for the potential to influence the proliferation of rat retinal precursor cells in vitro. Cells were isolated at embryonic day 19 and plated in standard proliferation medium in the presence or absence of fluid expressed from porcine vitreous humor. Cellular proliferation at different...... concentrations of vitreous fluid supplementation was quantified by using a (3)H-thymidine incorporation assay. Active components of vitreous fluid were partially characterized by gel filtration chromatography (GFC) and UV spectral analysis. The effect of each vitreous fraction on proliferation was determined...

  11. Esophageal squamous cell carcinoma - precursor lesions and early diagnosis

    Science.gov (United States)

    Lopes, Antonio Barros; Fagundes, Renato Borges

    2012-01-01

    Squamous cell carcinoma of the esophagus (SCCE) carries a poor prognosis due to late diagnosis. Early detection is highly desirable, since surgical and endoscopic resection offers the only possible cure for esophageal cancer. Population screening should be undertaken in high risk areas, and in low or moderate risk areas for people with risk factors (alcoholics, smokers, mate drinkers, history of head and neck cancer, achalasia and lye stricture of the esophagus). Esophageal balloon cytology is an easy and inexpensive sampling technique, but the current methods are insufficient for primary screening due to sampling errors. Conventional endoscopy with biopsy remains the standard procedure for the identification of pre-malignant and early malignant changes in esophageal mucosa and endoscopic detection. It may be enhanced by several techniques such as dye and optic chromoendoscopy, magnifying endoscopy, and optical-based spectroscopic and imaging modalities. Since more than 80% of SCCE deaths occur in developing countries, where expensive techniques such as narrow band imaging (NBI) and autofluorescence imaging are unavailable, the most cost-effective tool for targeting biopsies may be Lugol dye chromoendoscopy, since it is easy, accurate, inexpensive and available worldwide. In ideal conditions, or in developed countries, is it reasonable to think that optimal detection will require a combination of techniques, such as the combination of Lugol’s chromoendoscopy and NBI to identify esophageal areas that require further characterization by a high resolution technique. The efficacy and cost-effectiveness will determine whether these modalities will become part of standard endoscopy practice. PMID:22267978

  12. The regulation of the proliferation and differentiation of rat Leydig cell precursor cells after EDS administration or daily HCG treatment

    NARCIS (Netherlands)

    Teerds, K. J.; de rooij, D. G.; Rommerts, F. F.; Wensing, C. J.

    1988-01-01

    The proliferation and differentiation of possible Leydig cell precursors in adult rats were studied after destruction of the existing Leydig cells with EDS or after daily treatment with hCG. After 2 days with either treatment, a 12- to 16-fold increase in the number of [3H]thymidine-incorporating

  13. Generation, Release, and Uptake of the NAD Precursor Nicotinic Acid Riboside by Human Cells*

    Science.gov (United States)

    Kulikova, Veronika; Shabalin, Konstantin; Nerinovski, Kirill; Dölle, Christian; Niere, Marc; Yakimov, Alexander; Redpath, Philip; Khodorkovskiy, Mikhail; Migaud, Marie E.; Ziegler, Mathias; Nikiforov, Andrey

    2015-01-01

    NAD is essential for cellular metabolism and has a key role in various signaling pathways in human cells. To ensure proper control of vital reactions, NAD must be permanently resynthesized. Nicotinamide and nicotinic acid as well as nicotinamide riboside (NR) and nicotinic acid riboside (NAR) are the major precursors for NAD biosynthesis in humans. In this study, we explored whether the ribosides NR and NAR can be generated in human cells. We demonstrate that purified, recombinant human cytosolic 5′-nucleotidases (5′-NTs) CN-II and CN-III, but not CN-IA, can dephosphorylate the mononucleotides nicotinamide mononucleotide and nicotinic acid mononucleotide (NAMN) and thus catalyze NR and NAR formation in vitro. Similar to their counterpart from yeast, Sdt1, the human 5′-NTs require high (millimolar) concentrations of nicotinamide mononucleotide or NAMN for efficient catalysis. Overexpression of FLAG-tagged CN-II and CN-III in HEK293 and HepG2 cells resulted in the formation and release of NAR. However, NAR accumulation in the culture medium of these cells was only detectable under conditions that led to increased NAMN production from nicotinic acid. The amount of NAR released from cells engineered for increased NAMN production was sufficient to maintain viability of surrounding cells unable to use any other NAD precursor. Moreover, we found that untransfected HeLa cells produce and release sufficient amounts of NAR and NR under normal culture conditions. Collectively, our results indicate that cytosolic 5′-NTs participate in the conversion of NAD precursors and establish NR and NAR as integral constituents of human NAD metabolism. In addition, they point to the possibility that different cell types might facilitate each other's NAD supply by providing alternative precursors. PMID:26385918

  14. Generation, Release, and Uptake of the NAD Precursor Nicotinic Acid Riboside by Human Cells.

    Science.gov (United States)

    Kulikova, Veronika; Shabalin, Konstantin; Nerinovski, Kirill; Dölle, Christian; Niere, Marc; Yakimov, Alexander; Redpath, Philip; Khodorkovskiy, Mikhail; Migaud, Marie E; Ziegler, Mathias; Nikiforov, Andrey

    2015-11-06

    NAD is essential for cellular metabolism and has a key role in various signaling pathways in human cells. To ensure proper control of vital reactions, NAD must be permanently resynthesized. Nicotinamide and nicotinic acid as well as nicotinamide riboside (NR) and nicotinic acid riboside (NAR) are the major precursors for NAD biosynthesis in humans. In this study, we explored whether the ribosides NR and NAR can be generated in human cells. We demonstrate that purified, recombinant human cytosolic 5'-nucleotidases (5'-NTs) CN-II and CN-III, but not CN-IA, can dephosphorylate the mononucleotides nicotinamide mononucleotide and nicotinic acid mononucleotide (NAMN) and thus catalyze NR and NAR formation in vitro. Similar to their counterpart from yeast, Sdt1, the human 5'-NTs require high (millimolar) concentrations of nicotinamide mononucleotide or NAMN for efficient catalysis. Overexpression of FLAG-tagged CN-II and CN-III in HEK293 and HepG2 cells resulted in the formation and release of NAR. However, NAR accumulation in the culture medium of these cells was only detectable under conditions that led to increased NAMN production from nicotinic acid. The amount of NAR released from cells engineered for increased NAMN production was sufficient to maintain viability of surrounding cells unable to use any other NAD precursor. Moreover, we found that untransfected HeLa cells produce and release sufficient amounts of NAR and NR under normal culture conditions. Collectively, our results indicate that cytosolic 5'-NTs participate in the conversion of NAD precursors and establish NR and NAR as integral constituents of human NAD metabolism. In addition, they point to the possibility that different cell types might facilitate each other's NAD supply by providing alternative precursors. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  15. Extracellular Vesicles from Vascular Endothelial Cells Promote Survival, Proliferation and Motility of Oligodendrocyte Precursor Cells.

    Directory of Open Access Journals (Sweden)

    Masashi Kurachi

    Full Text Available We previously examined the effect of brain microvascular endothelial cell (MVEC transplantation on rat white matter infarction, and found that MVEC transplantation promoted remyelination of demyelinated axons in the infarct region and reduced apoptotic death of oligodendrocyte precursor cells (OPCs. We also found that the conditioned medium (CM from cultured MVECs inhibited apoptosis of cultured OPCs. In this study, we examined contribution of extracellular vesicles (EVs contained in the CM to its inhibitory effect on OPC apoptosis. Removal of EVs from the CM by ultracentrifugation reduced its inhibitory effect on OPC apoptosis. To confirm whether EVs derived from MVECs are taken up by cultured OPCs, we labeled EVs with PKH67, a fluorescent dye, and added them to OPC cultures. Many vesicular structures labeled with PKH67 were found within OPCs immediately after their addition. Next we examined the effect of MVEC-derived EVs on OPC behaviors. After 2 days in culture with EVs, there was significantly less pyknotic and more BrdU-positive OPCs when compared to control. We also examined the effect of EVs on motility of OPCs. OPCs migrated longer in the presence of EVs when compared to control. To examine whether these effects on cultured OPCs are shared by EVs from endothelial cells, we prepared EVs from conditioned media of several types of endothelial cells, and tested their effects on cultured OPCs. EVs from all types of endothelial cells we examined reduced apoptosis of OPCs and promoted their motility. Identification of the molecules contained in EVs from endothelial cells may prove helpful for establishment of effective therapies for demyelinating diseases.

  16. Alterations of neuronal precursor cells in stages of human adult neurogenesis in heroin addicts.

    Science.gov (United States)

    Bayer, Ronny; Franke, Heike; Ficker, Christoph; Richter, Monique; Lessig, Rüdiger; Büttner, Andreas; Weber, Marco

    2015-11-01

    Adult neurogenesis has been shown to occur throughout life and different brain pathologies were demonstrated to be associated with altered neurogenesis. Here, an impact of heroin addiction on neurogenesis in humans is hypothesised. Post mortem hippocampal specimens of drug addicts with known heroin abuse and a group of non-addictive control subjects were analysed, using antibodies indicating different stages of neurogenesis. The subgranular zone of the dentate gyrus was examined qualitatively and quantitatively. The data indicate (i) a decreased number of neural precursor cells, (ii) accompanied by low rates of proliferation and (iii) a marked loss of dendritic trees in targeting cells in heroin fatalities. (iv) The age-dependent increase of differentiating cells in the healthy controls was not observed in the addicts. Additionally, double immunofluorescence labelling indicated the precursor nature of Musashi-1 positive cells in the human subgranular zone of the dentate gyrus. Present data firstly demonstrate the influence of drug addiction with known heroin abuse on different developmental stages of progenitors in the dentate gyrus. The patterns of antibody staining suggest a distinct inhibition of neurogenesis at the stage of neural precursor cells and revealed morphological changes in targeting cells in cases of heroin addicts as compared to healthy controls. These alterations could be considerable for memory and cognitive deficits as well as addictive behaviour in chronic drug abusers and may give rise to specific pro-neurogenic therapies. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  17. Generation of dopaminergic neurons in the adult brain from mesencephalic precursor cells labeled with a nestin-GFP transgene.

    Science.gov (United States)

    Sawamoto, K; Nakao, N; Kakishita, K; Ogawa, Y; Toyama, Y; Yamamoto, A; Yamaguchi, M; Mori, K; Goldman, S A; Itakura, T; Okano, H

    2001-06-01

    Mesencephalic precursor cells may one day provide dopaminergic neurons for the treatment of Parkinson's disease. However, the generation of dopaminergic neurons from mesencephalic precursors has been difficult to follow, partly because an appropriate means for recognizing mesencephalic ventricular zone precursors has not been available. To visualize and isolate mesencephalic precursor cells from a mixed population, we used transgenic mice and rats carrying green fluorescent protein (GFP) cDNA under the control of the nestin enhancer. nestin-driven GFP was detected in the mesencephalic ventricular zone, and it colocalized with specific markers for neural precursor cells. In addition, data from flow-cytometry indicated that Prominin/CD133, a cell-surface marker for ventricular zone cells, was expressed specifically in these GFP-positive (GFP(+)) cells. After sorting by fluorescence-activated cell sorting, the GFP(+) cells proliferated in vitro and expressed precursor cell markers but not neuronal markers. Using clonogenic sphere formation assays, we showed that this sorted population was enriched in multipotent precursor cells that could differentiate into both neurons and glia. Importantly, many neurons generated from nestin-GFP-sorted mesencephalic precursors developed a dopaminergic phenotype in vitro. Finally, nestin-GFP(+) cells were transplanted into the striatum of a rat model of Parkinson's disease. Bromodeoxyuridine-tyrosine hydroxylase double-labeling revealed that the transplanted cells generated new dopaminergic neurons within the host striatum. The implanted cells were able to restore dopaminergic function in the host striatum, as assessed by a behavioral measure: recovery from amphetamine-induced rotation. Together, these findings indicate that precursor cells harvested from the embryonic ventral mesencephalon can generate dopaminergic neurons able to restore function to the chemically denervated adult striatum.

  18. Leukemia inhibitory factor favours neurogenic differentiation of long-term propagated human midbrain precursor cells

    DEFF Research Database (Denmark)

    Andersen, Rikke K; Widmer, Hans R; Zimmer, Jens

    2009-01-01

    There is a lot of excitement about the potential use of multipotent neural stem cells for the treatment of neurodegenerative diseases. However, the strategy is compromised by the general loss of multipotency and ability to generate neurons after long-term in vitro propagation. In the present study...... EGF+FGF2, EGF+FGF2+heparin or leukemia inhibitory factor (LIF; 10 ng/ml)+FGF2+heparin. Cultures were subsequently propagated for more than 180 days with NTS analyzed at various time-points. Our data show for the first time that human VM neural precursor cells can be long-term propagated as NTS......, human embryonic (5 weeks post-conception) ventral mesencephalic (VM) precursor cells were propagated as neural tissue-spheres (NTS) in epidermal growth factor (EGF; 20 ng/ml) and fibroblast growth factor 2 (FGF2; 20 ng/ml). After more than 325 days, the NTS were transferred to media containing either...

  19. Nestin-GFP Transgene Reveals Neural Precursor Cells in Adult Skeletal Muscle

    Science.gov (United States)

    Birbrair, Alexander; Wang, Zhong-Min; Messi, Maria Laura; Enikolopov, Grigori N.; Delbono, Osvaldo

    2011-01-01

    Background Therapy for neural lesions or degenerative diseases relies mainly on finding transplantable active precursor cells. Identifying them in peripheral tissues accessible for biopsy, outside the central nervous system, would circumvent the serious immunological and ethical concerns impeding cell therapy. Methodology/Principal Findings In this study, we isolated neural progenitor cells in cultured adult skeletal muscle from transgenic mice in which nestin regulatory elements control GFP expression. These cells also expressed the early neural marker Tuj1 and light and heavy neurofilament but not S100β, indicating that they express typical neural but not Schwann cell markers. GFP+/Tuj1+ cells were also negative for the endothelial and pericyte markers CD31 and α-smooth muscle actin, respectively. We established their a) functional response to glutamate in patch-clamp recordings; b) interstitial mesenchymal origin; c) replicative capacity; and d) the environment necessary for their survival after fluorescence-activated cell sorting. Conclusions/Significance We propose that the decline in nestin-GFP expression in muscle progenitor cells and its persistence in neural precursor cells in muscle cultures provide an invaluable tool for isolating a population of predifferentiated neural cells with therapeutic potential. PMID:21304812

  20. Hypoxia Epigenetically Confers Astrocytic Differentiation Potential on Human Pluripotent Cell-Derived Neural Precursor Cells

    Directory of Open Access Journals (Sweden)

    Tetsuro Yasui

    2017-06-01

    Full Text Available Human neural precursor cells (hNPCs derived from pluripotent stem cells display a high propensity for neuronal differentiation, but they require long-term culturing to differentiate efficiently into astrocytes. The mechanisms underlying this biased fate specification of hNPCs remain elusive. Here, we show that hypoxia confers astrocytic differentiation potential on hNPCs through epigenetic gene regulation, and that this was achieved by cooperation between hypoxia-inducible factor 1α and Notch signaling, accompanied by a reduction of DNA methylation level in the promoter region of a typical astrocyte-specific gene, Glial fibrillary acidic protein. Furthermore, we found that this hypoxic culture condition could be applied to rapid generation of astrocytes from Rett syndrome patient-derived hNPCs, and that these astrocytes impaired neuronal development. Thus, our findings shed further light on the molecular mechanisms regulating hNPC differentiation and provide attractive tools for the development of therapeutic strategies for treating astrocyte-mediated neurological disorders.

  1. Differentiation of human skin-derived precursor cells into functional islet-like insulin-producing cell clusters

    DEFF Research Database (Denmark)

    Mehrabi, Maryam; Mansouri, Kamran; Hosseinkhani, Saman

    2015-01-01

    Advances in cell-replacement strategies for diabetes have focused on renewable sources of glucose-responsive, insulin-producing cells (IPCs). One of the most proper alternatives is multipotent skin-derived precursors cells (SKPs), which can be differentiated into IPCs. In this study, we reported...... the isolation and expansion of human skin-derived precursors (hSKPs) followed by their differentiation into IPCs in vitro, through exposure to suitable differentiation factors. The gene expression of endocrine β cell markers was analyzed by reverse transcriptase-polymerase chain reaction. In addition, insulin......-dependent manner. These findings suggest that human SKPs can differentiate into functional IPCs. This may offer a safer cell source for future stem cell-based therapies....

  2. Nox2 and Nox4 influence neonatal c-kit(+) cardiac precursor cell status and differentiation.

    Science.gov (United States)

    Nadworny, Alyson S; Guruju, Mallik R; Poor, Daniel; Doran, Robert M; Sharma, Ram V; Kotlikoff, Michael I; Davisson, Robin L

    2013-09-15

    Redox status has emerged as critical in modulating stemness and lineage commitment in several precursor cell types. However, a role for redox genes, specifically NADPH oxidases (Nox), in cardiac precursor cells (CPCs) has not been established. We tested whether CPCs marked by type III receptor tyrosine kinase c-kit (c-kit(+)) exhibit a unique NADPH oxidase signature that confers precursor status and whether alterations in this profile are functionally linked to changes in lineage specification. Dihydroethidium (DHE) microfluorography indicated reduced basal reactive oxygen species (ROS) formation within early postnatal c-kit(+) CPCs. Real-time quantitative PCR revealed downregulation of ROS generator Nox2 and its subunit p67(phox) in c-kit(+) CPCs under basal conditions but upregulation of Nox2 and Nox4 over the course of differentiation. Adenoviral silencing of Nox2 and Nox4 increased expression of CPC markers c-kit and Flk-1 and blunted smooth and cardiac muscle differentiation, respectively, while overexpression of Nox2 and Nox4 significantly reduced c-kit expression. These changes were accompanied by altered expression of transcription factors regulating cardiac lineage commitment, Gata6 and Gata4, and cytokine transforming growth factor (TGF)-β1. Similar to other precursor cell types, RT(2)Profiler PCR Arrays revealed that c-kit(+) CPCs also exhibit enhanced antioxidant capacity at the mRNA level. In conclusion, we report that c-kit(+) CPCs demonstrate reduced Nox2 expression and ROS levels and that increases in Nox2 and Nox4 influence their differentiation into mature cells. We speculate that ROS generators Nox2 and Nox4, along with the antioxidant genes identified by PCR Arrays, may be novel targets in CPCs that could prove useful in cell-based therapy of the heart.

  3. Deficient leukemia inhibitory factor signaling in muscle precursor cells from patients with type 2 diabetes

    DEFF Research Database (Denmark)

    Broholm, Christa; Brandt, Claus; Schultz, Ninna S

    2012-01-01

    to LIF. The mRNA and protein expressions of LIF and its receptor (LIFR) were measured in skeletal muscle biopsies from healthy individuals and patients with type 2 diabetes by use of qPCR and Western blot. LIF signaling and response were studied following administration of recombinant LIF and si......The cytokine leukemia-inhibitory factor (LIF) is expressed by skeletal muscle and induces proliferation of muscle precursor cells, an important feature of skeletal muscle maintenance and repair. We hypothesized that muscle precursor cells from patients with type 2 diabetes had a deficient response......RNA knockdown of suppressor of cytokine signaling (SOCS)3 in myoblast cultures established from healthy individuals and patients with type 2 diabetes. Myoblast proliferation rate was assessed by bromodeoxyuridine incorporation. LIF and LIFR proteins were increased in both muscle tissue and cultured myoblasts...

  4. Derivation of Skeletal Myogenic Precursors from Human Pluripotent Stem Cells Using Conditional Expression of PAX7.

    Science.gov (United States)

    Darabi, Radbod; Perlingeiro, Rita C R

    2016-01-01

    Cell-based therapies are considered as one of the most promising approaches for the treatment of degenerating pathologies including muscle disorders and dystrophies. Advances in the approach of reprogramming somatic cells into induced pluripotent stem (iPS) cells allow for the possibility of using the patient's own pluripotent cells to generate specific tissues for autologous transplantation. In addition, patient-specific tissue derivatives have been shown to represent valuable material for disease modeling and drug discovery. Nevertheless, directed differentiation of pluripotent stem cells into a specific lineage is not a trivial task especially in the case of skeletal myogenesis, which is generally poorly recapitulated during the in vitro differentiation of pluripotent stem cells.Here, we describe a practical and efficient method for the derivation of skeletal myogenic precursors from differentiating human pluripotent stem cells using controlled expression of PAX7. Flow cytometry (FACS) purified myogenic precursors can be expanded exponentially and differentiated in vitro into myotubes, enabling researchers to use these cells for disease modeling as well as therapeutic purposes.

  5. Precursor B-cell lymphoblastic leukemia of the arm mimicking neurogenic tumor: case report

    Directory of Open Access Journals (Sweden)

    Sui Xiu-fang

    2012-07-01

    Full Text Available Abstract Precursor B-cell lymphoblastic lymphoma (PBLL is an infrequent subtype of lymphoblastic lymphoma (LBL that commonly affected site for the diagnosis is the skin, followed by the head and neck. In this report, we presented a special case of PBLL located at the left arm and detected with magnetic resonance imaging (MRI and ultrasonography (US. This kind of PBLL is similar to a peripheral nerve tumor in clinical and radiographic manifestation.

  6. Human Haemato-Endothelial Precursors: Cord Blood CD34+ Cells Produce Haemogenic Endothelium

    Science.gov (United States)

    Pelosi, Elvira; Castelli, Germana; Martin-Padura, Ines; Bordoni, Veronica; Santoro, Simona; Conigliaro, Alice; Cerio, Anna Maria; De Santis Puzzonia, Marco; Marighetti, Paola; Biffoni, Mauro; Alonzi, Tonino; Amicone, Laura; Alcalay, Myriam; Bertolini, Francesco; Testa, Ugo; Tripodi, Marco

    2012-01-01

    Embryologic and genetic evidence suggest a common origin of haematopoietic and endothelial lineages. In the murine embryo, recent studies indicate the presence of haemogenic endothelium and of a common haemato-endothelial precursor, the haemangioblast. Conversely, so far, little evidence supports the presence of haemogenic endothelium and haemangioblasts in later stages of development. Our studies indicate that human cord blood haematopoietic progenitors (CD34+45+144−), triggered by murine hepatocyte conditioned medium, differentiate into adherent proliferating endothelial precursors (CD144+CD105+CD146+CD31+CD45−) capable of functioning as haemogenic endothelium. These cells, proven to give rise to functional vasculature in vivo, if further instructed by haematopoietic growth factors, first switch to transitional CD144+45+ cells and then to haematopoietic cells. These results highlight the plasticity of haemato-endhothelial precursors in human post-natal life. Furthermore, these studies may provide highly enriched populations of human post-fetal haemogenic endothelium, paving the way for innovative projects at a basic and possibly clinical level. PMID:23226561

  7. Human haemato-endothelial precursors: cord blood CD34+ cells produce haemogenic endothelium.

    Directory of Open Access Journals (Sweden)

    Elvira Pelosi

    Full Text Available Embryologic and genetic evidence suggest a common origin of haematopoietic and endothelial lineages. In the murine embryo, recent studies indicate the presence of haemogenic endothelium and of a common haemato-endothelial precursor, the haemangioblast. Conversely, so far, little evidence supports the presence of haemogenic endothelium and haemangioblasts in later stages of development. Our studies indicate that human cord blood haematopoietic progenitors (CD34+45+144-, triggered by murine hepatocyte conditioned medium, differentiate into adherent proliferating endothelial precursors (CD144+CD105+CD146+CD31+CD45- capable of functioning as haemogenic endothelium. These cells, proven to give rise to functional vasculature in vivo, if further instructed by haematopoietic growth factors, first switch to transitional CD144+45+ cells and then to haematopoietic cells. These results highlight the plasticity of haemato-endhothelial precursors in human post-natal life. Furthermore, these studies may provide highly enriched populations of human post-fetal haemogenic endothelium, paving the way for innovative projects at a basic and possibly clinical level.

  8. Zinc Deficiency Induces Apoptosis via Mitochondrial p53- and Caspase-Dependent Pathways in Human Neuronal Precursor Cells

    Science.gov (United States)

    Seth, Rohit; Corniola, Rikki S.; Gower-Winter, Shannon D.; Morgan, Thomas J., Jr.; Bishop, Brian; Levenson, Cathy W.

    2015-01-01

    Previous studies have shown that zinc deficiency leads to apoptosis of neuronal precursor cells in vivo and in vitro. In addition to the role of p53 as a nuclear transcription factor in zinc deficient cultured human neuronal precursors (NT-2), we have now identified the translocation of phosphorylated p53 to the mitochondria and p53-dependent…

  9. Secretory clusterin inhibits osteoclastogenesis by attenuating M-CSF-dependent osteoclast precursor cell proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Bongkun; Kang, Soon-Suk [Department of Biomedical Sciences, University of Ulsan College of Medicine, Asan Medical Center, Seoul 138-736 (Korea, Republic of); Kang, Sang-Wook [Department of Biomedical Sciences, University of Ulsan College of Medicine, Asan Medical Center, Seoul 138-736 (Korea, Republic of); Department of Anatomy and Cell Biology, Cell Dysfunction Research Center and BMIT, University of Ulsan College of Medicine, Asan Medical Center, Seoul 138-736 (Korea, Republic of); Min, Bon-Hong [Department of Pharmacology, Korea University College of Medicine, Seoul 136-705 (Korea, Republic of); Lee, Eun-Jin; Song, Da-Hyun; Kim, Sang-Min [Department of Biomedical Sciences, University of Ulsan College of Medicine, Asan Medical Center, Seoul 138-736 (Korea, Republic of); Song, Youngsup [Department of Biomedical Sciences, University of Ulsan College of Medicine, Asan Medical Center, Seoul 138-736 (Korea, Republic of); Department of Anatomy and Cell Biology, Cell Dysfunction Research Center and BMIT, University of Ulsan College of Medicine, Asan Medical Center, Seoul 138-736 (Korea, Republic of); Yoon, Seung-Yong [Department of Anatomy and Cell Biology, Cell Dysfunction Research Center and BMIT, University of Ulsan College of Medicine, Asan Medical Center, Seoul 138-736 (Korea, Republic of); Chang, Eun-Ju, E-mail: ejchang@amc.seoul.kr [Department of Biomedical Sciences, University of Ulsan College of Medicine, Asan Medical Center, Seoul 138-736 (Korea, Republic of); Department of Anatomy and Cell Biology, Cell Dysfunction Research Center and BMIT, University of Ulsan College of Medicine, Asan Medical Center, Seoul 138-736 (Korea, Republic of)

    2014-07-18

    Highlights: • We describe the expression and secretion of clusterin in osteoclasts. • Endogenous clusterin deficiency does not affect osteoclast formation. • Exogenous treatment with secretory clusterin decreases osteoclast differentiation. • Secretory clusterin attenuates osteoclast precursor cell proliferation by inhibiting M-CSF-mediated ERK activation. - Abstract: Secretory clusterin (sCLU)/apolipoprotein J is a multifunctional glycoprotein that is ubiquitously expressed in various tissues. Reduced sCLU in the joints of patients with bone erosive disease is associated with disease activity; however, its exact role has yet to be elucidated. Here, we report that CLU is expressed and secreted during osteoclastogenesis in mouse bone marrow-derived macrophages (BMMs) that are treated with receptor activator of nuclear factor kappa-B ligand (RANKL) and macrophage colony-stimulating factor (M-CSF). CLU-deficient BMMs obtained from CLU{sup −/−} mice exhibited no significant alterations in OC differentiation in comparison with BMMs obtained from wild-type mice. In contrast, exogenous sCLU treatment significantly inhibited OC formation in both BMMs and OC precursor cultures. The inhibitory effect of sCLU was more prominent in BMMs than OC precursor cultures. Interestingly, treating BMMs with sCLU decreased the proliferative effects elicited by M-CSF and suppressed M-CSF-induced ERK activation of OC precursor cells without causing apoptotic cell death. This study provides the first evidence that sCLU reduces OC formation by inhibiting the actions of M-CSF, thereby suggesting its protective role in bone erosion.

  10. Platelet-derived growth factor BB enhances osteoclast formation and osteoclast precursor cell chemotaxis.

    Science.gov (United States)

    Li, Dian-Qi; Wan, Qi-Long; Pathak, Janak L; Li, Zu-Bing

    2017-07-01

    Enhanced osteoclast formation increases bone resorption, which triggers bone remodeling. Platelet-derived growth factor BB (PDGF-BB) enhances precursor cell homing, angiogenesis, and bone healing, and thereby could also treat osteoporosis. However, the effect of PDGF-BB on osteoclast formation is not fully understood. We investigated whether exogenous recombinant PDGF-BB directly affects osteoclast formation and osteoclast precursor cell chemotaxis. The murine monocyte-macrophage cell line RAW264.7 and bone-marrow-derived macrophages were cultured with recombinant mouse PDGF-BB with or without a platelet-derived growth factor receptor β inhibitor (AG-1295) or a Janus kinase 2 inhibitor (AG-490) to analyze the effect on osteoclastogenesis in vitro. PDGF-BB with or without AG-490 or AG-1295 was locally administrated in the mandibular fracture of 16-week-old Sprague Dawley rats (n = 18) for 1-2 weeks to analyze the effect on osteoclastogenesis in vivo. The effect of the treatments on osteoclast formation, osteoclast precursor cell migration, and expression of osteoclastogenic signaling molecules was analyzed. PDGF-BB enhanced osteoclast formation both in vitro and in vivo, but AG-490 and AG-1295 inhibited this effect. PDGF-BB enhanced phosphorylation of extracellular-signal-regulated kinase 1/2 (ERK1/2), Akt, and signal transducer and activator of transcription 3 (STAT3) in RAW264.7 cells. AG-490 inhibited PDGF-BB-induced STAT3 phosphorylation. PDGF-BB enhanced RAW264.7 cell migration and gene expression of osteoclastogenic signaling molecules (i.e., nuclear factor of activated T cells 1, dendrocyte-expressed seven transmembrane protein, and B-cell lymphoma 2), and treatment with AG-1295, AG-490, or S3I-201 (a STAT3 inhibitor) reduced this effect. PDGF-BB enhanced osteoclast formation, osteoclast precursor cell chemotaxis, and phosphorylation of STAT3, Akt, and ERK1/2. but AG-1295 and AG-490 reduced this effect. These findings reflect the complexity of

  11. Emerging role of immunotherapy in precursor B-cell acute lymphoblastic leukemia.

    Science.gov (United States)

    Valecha, Gautam Kishore; Ibrahim, Uroosa; Ghanem, Sassine; Asti, Divya; Atallah, Jean-Paul; Terjanian, Terenig

    2017-09-01

    Acute lymphoblastic leukemia (ALL) is an aggressive type of leukemia that carries poor prognosis in adults especially in the setting of high risk cytogenetics and relapsed/refractory (R/R) disease. Advancements in immunotherapy have led to the development of several monoclonal antibodies (MoAbs) and chimeric antigen receptor (CAR) T cells that are capable of targeting certain surface antigens on leukemic cells, resulting in their destruction. Areas covered: This article reviews the mechanism of action, outcomes of various trials, and adverse effects of MoAbs and CAR-T cells used in the treatment of precursor B-cell ALL. Expert commentary: Some of the immunotherapeutic agents that have been approved for the treatment of R/R precursor B-cell ALL have shown superior efficacy and safety profile compared to chemotherapy in advanced disease. Several trials are now being conducted to evaluate the role of certain MoAbs in combination with chemotherapy in the treatment of B-cell ALL. Additionally, their use in the frontline setting with more favorable host characteristics may also result in superior outcomes compared to the current standard of care.

  12. Msx genes define a population of mural cell precursors required for head blood vessel maturation.

    Science.gov (United States)

    Lopes, Miguel; Goupille, Olivier; Saint Cloment, Cécile; Lallemand, Yvan; Cumano, Ana; Robert, Benoît

    2011-07-01

    Vessels are primarily formed from an inner endothelial layer that is secondarily covered by mural cells, namely vascular smooth muscle cells (VSMCs) in arteries and veins and pericytes in capillaries and veinules. We previously showed that, in the mouse embryo, Msx1(lacZ) and Msx2(lacZ) are expressed in mural cells and in a few endothelial cells. To unravel the role of Msx genes in vascular development, we have inactivated the two Msx genes specifically in mural cells by combining the Msx1(lacZ), Msx2(lox) and Sm22α-Cre alleles. Optical projection tomography demonstrated abnormal branching of the cephalic vessels in E11.5 mutant embryos. The carotid and vertebral arteries showed an increase in caliber that was related to reduced vascular smooth muscle coverage. Taking advantage of a newly constructed Msx1(CreERT2) allele, we demonstrated by lineage tracing that the primary defect lies in a population of VSMC precursors. The abnormal phenotype that ensues is a consequence of impaired BMP signaling in the VSMC precursors that leads to downregulation of the metalloprotease 2 (Mmp2) and Mmp9 genes, which are essential for cell migration and integration into the mural layer. Improper coverage by VSMCs secondarily leads to incomplete maturation of the endothelial layer. Our results demonstrate that both Msx1 and Msx2 are required for the recruitment of a population of neural crest-derived VSMCs.

  13. MECHANICAL VIBRATION INHIBITS OSTEOCLAST FORMATION BY REDUCING DC-STAMP RECEPTOR EXPRESSION IN OSTEOCLAST PRECURSOR CELLS

    Science.gov (United States)

    Kulkarni, R.N.; Voglewede, P.A.; Liu, D.

    2014-01-01

    It is well known that physical inactivity leads to loss of muscle mass, but it also causes bone loss. Mechanistically, osteoclastogenesis and bone resorption have recently been shown to be regulated by vibration. However, the underlying mechanism behind the inhibition of osteoclast formation is yet unknown. Therefore, we investigated whether mechanical vibration of osteoclast precursor cells affects osteoclast formation by the involvement of fusion-related molecules such as dendritic cell-specific transmembrane protein (DC-STAMP), and P2X7 receptor (P2X7R). RAW264.7 (a murine osteoclastic-like cell line) cells were treated with 20 ng/ml receptor activator of NF-κB ligand (RANKL). For 3 consecutive days, the cells were subjected to 1 hour of mechanical vibration with 20 µm displacement at a frequency of 4 Hz and compared to the control cells that were treated under the same condition but without the vibration. After 5 days of culture, osteoclast formation was determined. Gene expression of DC-STAMP and P2X7R by RAW264.7 cells were determined after 1 hour mechanical vibration, while protein production of the DC-STAMP was determined after 6 hours of post incubation after vibration. As a result, mechanical vibration of RAW264.7 cells inhibited the formation of osteoclasts. Vibration down-regulated DC-STAMP gene expression by 1.6-fold in the presence of RANKL and by 1.4-fold in the absence of RANKL. Additionally, DC-STAMP protein production was also down-regulated by 1.4-fold in the presence of RANKL and by 1.2-fold in the absence of RANKL in RAW264.7 cells in response to mechanical vibration. However, vibration did not affect P2X7R gene expression. Mouse anti-DC-STAMP antibody inhibited osteoclast formation in the absence of vibration. Our results suggest that mechanical vibration of osteoclast precursor cells reduce DC-STAMP expression in osteoclast precursor cells leading to the inhibition of osteoclast formation. PMID:23994170

  14. Gum hypertrophy - an unusual presenting feature in a case of precursor T-cell acute lymphoblastic leukemia

    National Research Council Canada - National Science Library

    Premalata, Chennagiri Srinivasamurthy; Madhumati, Davanam Satyanarayana; Lakshmidevi, Vishweshwariah; Pradeep, Rudramurthy; Appaji, Lingappa; Mukherjee, Geetashree

    2008-01-01

    ... and the central nervous system. We present a rare case of precursor T-cell acute lymphoblastic leukemia/lymphoma with initial oral manifestation, presenting with the unusual features of gum hypertrophy and involvement of upper jaw...

  15. The hemopoietic microenvironment : effects of chemotherapy and irradiation

    NARCIS (Netherlands)

    P.G.J. Nikkels (Peter)

    1989-01-01

    textabstractBlood consists of plasma containing cells and cell fragments. Three groups of blood cells can be identified, namely (a) red blood cells or erythrocytes, (b) white blood cells or leucocytes and (c) platelets or thrombocytes. The white blood cells can be separated into neutrophilic-,

  16. Immortalization of different precursors of glial cells with a targeted and temperature-sensitive oncogene.

    Science.gov (United States)

    Bernard, R; Le Bert, M; Borde, I; Galiana, E; Evrard, C; Rouget, P

    1994-09-01

    Different types of glial precursor cell lines were obtained after stable transfection of brain cells with the pJC-SVLTtsA vector carrying the tsA58 simian virus 40 large T (SVLT) gene driven by the promoter of a gliotropic strain of JC papovavirus. The immortalized cells were conditional for growth: they expressed the SVLT antigen and proliferated at 34 degrees C, but their growth was either reduced or arrested when they were shifted to 39 degrees C. The differentiation characteristics of four representative lines were more extensively studied. The CR15 and CM8 lines displayed properties of bipotential glial progenitors: they were able to express oligodendrocyte markers at both temperatures, but could differentiate into astrocytes only at 39 degrees C. In contrast, the CR19 and CM3r lines corresponded to more committed oligodendrocyte precursors: they expressed various oligodendroglial markers but they could not synthesize the glial fibrillary acidic protein. More particularly, the CM3r mouse cells displayed a typical oligodendrocyte progenitor morphology and expressed the proteolipid protein mRNA.

  17. Effects of heavy-ion radiosurgery on the hemopoietic function of the silkworm Bombyx mori

    Energy Technology Data Exchange (ETDEWEB)

    Tu, Zhen-Li; Kobayashi, Yasuhiko; Watanabe, Hiroshi; Yamamoto, Kazuo [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; Kiguchi, Kenji [SHINSHU Univ., Ueda, Nagano (Japan). Faculty of Textile Science and Technology

    2002-09-01

    To study the effects of heavy-ion radiosurgery on the hemopoietic function of a silkworm, hemopoietic organs of larvae were locally irradiated with carbon-ion beams, and the changes in the hemocyte density and in the hemocyte function were investigated. When the larvae were irradiated by 50 Gy to 300 Gy carbon ions on the 3rd day of the 4th instar, the hemocyte densities did not change for a while, though they gradually increased at a later stage, but were finally still significantly lower than those of unirradiated controls. The hemocyte densities of the larvae irradiated at different developmental stages showed suppressed increments, and carbon-ion irradiation given to larvae at early stages compared to the later stages had a significant suppressive effect on the hemocyte densities. On unilateral irradiated larvae a hemocyte intermediate increment between those of bilateral irradiated larvae and unirradiated controls was observed. The percentage of dead hemocytes was obviously higher for irradiated larvae than unirradiated controls during the later 5th instar. Thus, it is evident that carbon-ion radiosurgery on hemopoietic organs of silkworm induced not only a quantitative change, but also a qualitative change in the hemocytes. (author)

  18. A subpopulation of smooth muscle cells, derived from melanocyte-competent precursors, prevents patent ductus arteriosus.

    Directory of Open Access Journals (Sweden)

    Ichiro Yajima

    Full Text Available BACKGROUND: Patent ductus arteriosus is a life-threatening condition frequent in premature newborns but also present in some term infants. Current mouse models of this malformation generally lead to perinatal death, not reproducing the full phenotypic spectrum in humans, in whom genetic inheritance appears complex. The ductus arteriosus (DA, a temporary fetal vessel that bypasses the lungs by shunting the aortic arch to the pulmonary artery, is constituted by smooth muscle cells of distinct origins (SMC1 and SMC2 and many fewer melanocytes. To understand novel mechanisms preventing DA closure at birth, we evaluated the importance of cell fate specification in SMC that form the DA during embryonic development. Upon specific Tyr::Cre-driven activation of Wnt/β-catenin signaling at the time of cell fate specification, melanocytes replaced the SMC2 population of the DA, suggesting that SMC2 and melanocytes have a common precursor. The number of SMC1 in the DA remained similar to that in controls, but insufficient to allow full DA closure at birth. Thus, there was no cellular compensation by SMC1 for the loss of SMC2. Mice in which only melanocytes were genetically ablated after specification from their potential common precursor with SMC2, demonstrated that differentiated melanocytes themselves do not affect DA closure. Loss of the SMC2 population, independent of the presence of melanocytes, is therefore a cause of patent ductus arteriosus and premature death in the first months of life. Our results indicate that patent ductus arteriosus can result from the insufficient differentiation, proliferation, or contractility of a specific smooth muscle subpopulation that shares a common neural crest precursor with cardiovascular melanocytes.

  19. A Subpopulation of Smooth Muscle Cells, Derived from Melanocyte-Competent Precursors, Prevents Patent Ductus Arteriosus

    Science.gov (United States)

    Puig, Isabel; Champeval, Delphine; Kumasaka, Mayuko; Belloir, Elodie; Bonaventure, Jacky; Mark, Manuel; Yamamoto, Hiroaki; Taketo, Mark M.; Choquet, Philippe; Etchevers, Heather C.; Beermann, Friedrich; Delmas, Véronique; Monassier, Laurent; Larue, Lionel

    2013-01-01

    Background Patent ductus arteriosus is a life-threatening condition frequent in premature newborns but also present in some term infants. Current mouse models of this malformation generally lead to perinatal death, not reproducing the full phenotypic spectrum in humans, in whom genetic inheritance appears complex. The ductus arteriosus (DA), a temporary fetal vessel that bypasses the lungs by shunting the aortic arch to the pulmonary artery, is constituted by smooth muscle cells of distinct origins (SMC1 and SMC2) and many fewer melanocytes. To understand novel mechanisms preventing DA closure at birth, we evaluated the importance of cell fate specification in SMC that form the DA during embryonic development. Upon specific Tyr::Cre-driven activation of Wnt/β-catenin signaling at the time of cell fate specification, melanocytes replaced the SMC2 population of the DA, suggesting that SMC2 and melanocytes have a common precursor. The number of SMC1 in the DA remained similar to that in controls, but insufficient to allow full DA closure at birth. Thus, there was no cellular compensation by SMC1 for the loss of SMC2. Mice in which only melanocytes were genetically ablated after specification from their potential common precursor with SMC2, demonstrated that differentiated melanocytes themselves do not affect DA closure. Loss of the SMC2 population, independent of the presence of melanocytes, is therefore a cause of patent ductus arteriosus and premature death in the first months of life. Our results indicate that patent ductus arteriosus can result from the insufficient differentiation, proliferation, or contractility of a specific smooth muscle subpopulation that shares a common neural crest precursor with cardiovascular melanocytes. PMID:23382837

  20. Higher vulnerability and stress sensitivity of neuronal precursor cells carrying an alpha-synuclein gene triplication.

    Directory of Open Access Journals (Sweden)

    Adrian Flierl

    Full Text Available Parkinson disease (PD is a multi-factorial neurodegenerative disorder with loss of dopaminergic neurons in the substantia nigra and characteristic intracellular inclusions, called Lewy bodies. Genetic predisposition, such as point mutations and copy number variants of the SNCA gene locus can cause very similar PD-like neurodegeneration. The impact of altered α-synuclein protein expression on integrity and developmental potential of neuronal stem cells is largely unexplored, but may have wide ranging implications for PD manifestation and disease progression. Here, we investigated if induced pluripotent stem cell-derived neuronal precursor cells (NPCs from a patient with Parkinson's disease carrying a genomic triplication of the SNCA gene (SNCA-Tri. Our goal was to determine if these cells these neuronal precursor cells already display pathological changes and impaired cellular function that would likely predispose them when differentiated to neurodegeneration. To achieve this aim, we assessed viability and cellular physiology in human SNCA-Tri NPCs both under normal and environmentally stressed conditions to model in vitro gene-environment interactions which may play a role in the initiation and progression of PD. Human SNCA-Tri NPCs displayed overall normal cellular and mitochondrial morphology, but showed substantial changes in growth, viability, cellular energy metabolism and stress resistance especially when challenged by starvation or toxicant challenge. Knockdown of α-synuclein in the SNCA-Tri NPCs by stably expressed short hairpin RNA (shRNA resulted in reversal of the observed phenotypic changes. These data show for the first time that genetic alterations such as the SNCA gene triplication set the stage for decreased developmental fitness, accelerated aging, and increased neuronal cell loss. The observation of this "stem cell pathology" could have a great impact on both quality and quantity of neuronal networks and could provide a

  1. Tumefactive intracranial presentation of precursor B-cell acute lymphoblastic leukemia

    Energy Technology Data Exchange (ETDEWEB)

    Forester, Craig M. [University of Utah, Salt Lake City, UT (United States); Braunreiter, Chi L. [University of Utah, Division of Pediatric Hematology Oncology, Primary Children' s Medical Center, Salt Lake City, UT (United States); Helen DeVos Children' s Hospital, Department of Pediatric Hematology Oncology, Grand Rapids, MI (United States); Yaish, Hasan; Afify, Zeinab [University of Utah, Division of Pediatric Hematology Oncology, Primary Children' s Medical Center, Salt Lake City, UT (United States); Hedlund, Gary L. [Primary Children' s Medical Center, Department of Pediatric Radiology, Salt Lake City, UT (United States)

    2009-11-15

    In children, leukemia is the most common malignancy, and approximately 75% of leukemias are acute lymphoblastic leukemia (ALL). Central nervous system leukemia is found at diagnosis in fewer than 5% of children with ALL. Leukemic intracranial masses have been described with acute myeloid leukemia, but ALL presenting as a mass lesion is rare. We describe a unique case of an intracranial confirmed precursor B cell (pre-B) ALL mass in a 13-year-old girl that was diagnosed by brain CT, MRI and cerebral angiography, and confirmed by biopsy. This report details pertinent history and distinguishing imaging features of an intracranial ALL tumefaction. (orig.)

  2. CD28 facilitates the generation of Foxp3− cytokine responsive regulatory T cell precursors1

    Science.gov (United States)

    Lio, Chan-Wang J.; Dodson, Lindzy F.; Deppong, Christine M.; Hsieh, Chyi-Song; Green, Jonathan M.

    2010-01-01

    The T cell co-stimulatory molecule CD28 plays an important role in the thymic generation of Foxp3+ regulatory T (Treg) cells essential for the maintenance of self-tolerance. Here, we show that a cell-intrinsic signal from CD28 is involved in the generation of cytokine-responsive Foxp3− precursors using studies of mixed bone marrow chimeras, as well as TCR-specific generation of Foxp3+ cells using intrathymic transfer of TCR transgenic thymocytes expressing a natural Treg TCR. Contrary to a previous report, the analysis of CD28 mutant knock-in mice revealed that this cell-intrinsic signal is only partially dependent on the Lck-binding PYAP motif. Surprisingly, even though the absence of CD28 resulted in a 6-fold decrease in thymic Treg cells, the TCR repertoires of CD28-deficient and sufficient cells were largely overlapping. Thus, these data suggest that CD28 does not operate by markedly enlarging the repertoire of TCRs available for Treg cell development, but rather by improving the efficiency of Treg cell development of thymocytes expressing natural Treg TCRs. PMID:20421644

  3. Serum of patients with active rheumatoid arthritis inhibits differentiation of osteochondrogenic precursor cells.

    Science.gov (United States)

    Pathak, Janak L; Verschueren, Patrick; Lems, Willem F; Bravenboer, Nathalie; Klein-Nulend, Jenneke; Bakker, Astrid D; Luyten, Frank P

    2016-05-01

    Delayed fracture healing is frequently experienced in patients with systemic inflammation such as during rheumatoid arthritis (RA). The reasons for this are diverse, but could also be caused by inflammatory cytokines and/or growth factors in serum from patients with active disease. We hypothesized that serum from patients with active RA contains circulating inflammatory factors that inhibit differentiation of osteochondrogenic precursors. Serum was obtained from 15 patients with active RA (active RA-sera) and from the same patients in clinical remission 1 year later (remission RA-sera; controls). The effect of active RA-sera on osteochondrogenic differentiation of chondrogenic ATDC5 cells and primary human periosteum-derived progenitor cells (HPDC) was determined in micromass culture. In ATDC5 cells, active RA-sera reduced Ki67 transcription levels by 40% and cartilage matrix accumulation by 14% at day 14, and Alp transcription levels by 16%, and matrix mineralization by 17% at day 21 compared with remission RA-sera. In HPDCs, active RA-sera inhibited metabolic activity by 8%, SOX9 transcription levels by 14%, and cartilage matrix accumulation by 7% at day 7 compared with remission RA-sera. In conclusion, sera from patients with active RA negatively affect differentiation of osteochondrogenic precursors, and as a consequence may contribute to delayed fracture healing in these patients.

  4. Stochastic specification of primordial germ cells from mesoderm precursors in axolotl embryos.

    Science.gov (United States)

    Chatfield, Jodie; O'Reilly, Marie-Anne; Bachvarova, Rosemary F; Ferjentsik, Zoltan; Redwood, Catherine; Walmsley, Maggie; Patient, Roger; Loose, Mathew; Johnson, Andrew D

    2014-06-01

    A common feature of development in most vertebrate models is the early segregation of the germ line from the soma. For example, in Xenopus and zebrafish embryos primordial germ cells (PGCs) are specified by germ plasm that is inherited from the egg; in mice, Blimp1 expression in the epiblast mediates the commitment of cells to the germ line. How these disparate mechanisms of PGC specification evolved is unknown. Here, in order to identify the ancestral mechanism of PGC specification in vertebrates, we studied PGC specification in embryos from the axolotl (Mexican salamander), a model for the tetrapod ancestor. In the axolotl, PGCs develop within mesoderm, and classic studies have reported their induction from primitive ectoderm (animal cap). We used an axolotl animal cap system to demonstrate that signalling through FGF and BMP4 induces PGCs. The role of FGF was then confirmed in vivo. We also showed PGC induction by Brachyury, in the presence of BMP4. These conditions induced pluripotent mesodermal precursors that give rise to a variety of somatic cell types, in addition to PGCs. Irreversible restriction of the germ line did not occur until the mid-tailbud stage, days after the somatic germ layers are established. Before this, germline potential was maintained by MAP kinase signalling. We propose that this stochastic mechanism of PGC specification, from mesodermal precursors, is conserved in vertebrates. © 2014. Published by The Company of Biologists Ltd.

  5. Non-PGM cathode catalysts for fuel cell application derived from heat treated heteroatomic amines precursors

    Science.gov (United States)

    Serov, Alexey; Halevi, Barr; Artyushkova, Kateryna; Atanassov, Plamen B; Martinez, Ulises A

    2017-04-25

    A method of preparing M-N--C catalysts utilizing a sacrificial support approach and inexpensive and readily available polymer precursors as the source of nitrogen and carbon is disclosed. Exemplary polymer precursors include non-porphyrin precursors with no initial catalytic activity. Examples of suitable non-catalytic non-porphyrin precursors include, but are not necessarily limited to low molecular weight precursors that form complexes with iron such as 4-aminoantipirine, phenylenediamine, hydroxysuccinimide, ethanolamine, and the like.

  6. Amyloid precursor protein regulates migration and metalloproteinase gene expression in prostate cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Miyazaki, Toshiaki; Ikeda, Kazuhiro; Horie-Inoue, Kuniko [Division of Gene Regulation and Signal Transduction, Research Center for Genomic Medicine, Saitama Medical University, Saitama 350-1241 (Japan); Inoue, Satoshi, E-mail: INOUE-GER@h.u-tokyo.ac.jp [Division of Gene Regulation and Signal Transduction, Research Center for Genomic Medicine, Saitama Medical University, Saitama 350-1241 (Japan); Department of Geriatric Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo 113-8655 (Japan); Department of Anti-Aging Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo 113-8655 (Japan)

    2014-09-26

    Highlights: • APP knockdown reduced proliferation and migration of prostate cancer cells. • APP knockdown reduced expression of metalloproteinase and EMT-related genes. • APP overexpression promoted LNCaP cell migration. • APP overexpression increased expression of metalloproteinase and EMT-related genes. - Abstract: Amyloid precursor protein (APP) is a type I transmembrane protein, and one of its processed forms, β-amyloid, is considered to play a central role in the development of Alzheimer’s disease. We previously showed that APP is a primary androgen-responsive gene in prostate cancer and that its increased expression is correlated with poor prognosis for patients with prostate cancer. APP has also been implicated in several human malignancies. Nevertheless, the mechanism underlying the pro-proliferative effects of APP on cancers is still not well-understood. In the present study, we explored a pathophysiological role for APP in prostate cancer cells using siRNA targeting APP (siAPP). The proliferation and migration of LNCaP and DU145 prostate cancer cells were significantly suppressed by siAPP. Differentially expressed genes in siAPP-treated cells compared to control siRNA-treated cells were identified by microarray analysis. Notably, several metalloproteinase genes, such as ADAM10 and ADAM17, and epithelial–mesenchymal transition (EMT)-related genes, such as VIM, and SNAI2, were downregulated in siAPP-treated cells as compared to control cells. The expression of these genes was upregulated in LNCaP cells stably expressing APP when compared with control cells. APP-overexpressing LNCaP cells exhibited enhanced migration in comparison to control cells. These results suggest that APP may contribute to the proliferation and migration of prostate cancer cells by modulating the expression of metalloproteinase and EMT-related genes.

  7. In vitro epigenetic reprogramming of human cardiac mesenchymal stromal cells into functionally competent cardiovascular precursors.

    Directory of Open Access Journals (Sweden)

    Matteo Vecellio

    Full Text Available Adult human cardiac mesenchymal-like stromal cells (CStC represent a relatively accessible cell type useful for therapy. In this light, their conversion into cardiovascular precursors represents a potential successful strategy for cardiac repair. The aim of the present work was to reprogram CStC into functionally competent cardiovascular precursors using epigenetically active small molecules. CStC were exposed to low serum (5% FBS in the presence of 5 µM all-trans Retinoic Acid (ATRA, 5 µM Phenyl Butyrate (PB, and 200 µM diethylenetriamine/nitric oxide (DETA/NO, to create a novel epigenetically active cocktail (EpiC. Upon treatment the expression of markers typical of cardiac resident stem cells such as c-Kit and MDR-1 were up-regulated, together with the expression of a number of cardiovascular-associated genes including KDR, GATA6, Nkx2.5, GATA4, HCN4, NaV1.5, and α-MHC. In addition, profiling analysis revealed that a significant number of microRNA involved in cardiomyocyte biology and cell differentiation/proliferation, including miR 133a, 210 and 34a, were up-regulated. Remarkably, almost 45% of EpiC-treated cells exhibited a TTX-sensitive sodium current and, to a lower extent in a few cells, also the pacemaker I(f current. Mechanistically, the exposure to EpiC treatment introduced global histone modifications, characterized by increased levels of H3K4Me3 and H4K16Ac, as well as reduced H4K20Me3 and H3s10P, a pattern compatible with reduced proliferation and chromatin relaxation. Consistently, ChIP experiments performed with H3K4me3 or H3s10P histone modifications revealed the presence of a specific EpiC-dependent pattern in c-Kit, MDR-1, and Nkx2.5 promoter regions, possibly contributing to their modified expression. Taken together, these data indicate that CStC may be epigenetically reprogrammed to acquire molecular and biological properties associated with competent cardiovascular precursors.

  8. Rejuvenation of MPTP-induced human neural precursor cell senescence by activating autophagy

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Liang [East Hospital, Tongji University School of Medicine, Shanghai (China); Dong, Chuanming [East Hospital, Tongji University School of Medicine, Shanghai (China); Department of Anatomy and Neurobiology, The Jiangsu Key Laboratory of Neuroregeneration, Nantong University, Nantong (China); Sun, Chenxi; Ma, Rongjie; Yang, Danjing [East Hospital, Tongji University School of Medicine, Shanghai (China); Zhu, Hongwen, E-mail: hongwen_zhu@hotmail.com [Tianjin Hospital, Tianjin Academy of Integrative Medicine, Tianjin (China); Xu, Jun, E-mail: xunymc2000@yahoo.com [East Hospital, Tongji University School of Medicine, Shanghai (China)

    2015-08-21

    Aging of neural stem cell, which can affect brain homeostasis, may be caused by many cellular mechanisms. Autophagy dysfunction was found in aged and neurodegenerative brains. However, little is known about the relationship between autophagy and human neural stem cell (hNSC) aging. The present study used 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP) to treat neural precursor cells (NPCs) derived from human embryonic stem cell (hESC) line H9 and investigate related molecular mechanisms involved in this process. MPTP-treated NPCs were found to undergo premature senescence [determined by increased senescence-associated-β-galactosidase (SA-β-gal) activity, elevated intracellular reactive oxygen species level, and decreased proliferation] and were associated with impaired autophagy. Additionally, the cellular senescence phenotypes were manifested at the molecular level by a significant increase in p21 and p53 expression, a decrease in SOD2 expression, and a decrease in expression of some key autophagy-related genes such as Atg5, Atg7, Atg12, and Beclin 1. Furthermore, we found that the senescence-like phenotype of MPTP-treated hNPCs was rejuvenated through treatment with a well-known autophagy enhancer rapamycin, which was blocked by suppression of essential autophagy gene Beclin 1. Taken together, these findings reveal the critical role of autophagy in the process of hNSC aging, and this process can be reversed by activating autophagy. - Highlights: • We successfully establish hESC-derived neural precursor cells. • MPTP treatment induced senescence-like state in hESC-derived NPCs. • MPTP treatment induced impaired autophagy of hESC-derived NPCs. • MPTP-induced hESC-derived NPC senescence was rejuvenated by activating autophagy.

  9. Biochemical precursor effects on the fatty acid production in cell suspension cultures of Theobroma cacao L.

    Science.gov (United States)

    Parra, O; Gallego, A M; Urrea, A; Rojas, L F; Correa, C; Atehortúa, L

    2017-02-01

    Cocoa butter (CB) is composed of 96% palmitic, stearic, oleic, linoleic and linolenic fatty acids that are responsible for the hardness, texture and fusion properties of chocolate. Through in vitro plant cell culture it is possible to modify CB lipid profiles and to study the fatty acid biosynthesis pathway on a subcellular level, evaluating fundamental aspects to enhance in vitro fatty acid production in a specific and controlled way. In this research, culture media was supplemented with acetate, biotin, pyruvate, bicarbonate and glycerol at three different concentrations and the effects on the biomass production (g/L), cell viability, and fatty acids profile and production was evaluated in in vitro cell suspensions culture. It was found that biotin stimulated fatty acid synthesis without altering cell viability and cell growth. It was also evident a change in the lipid profile of cell suspensions, increasing middle and long chain fatty acids proportion, which are unusual to those reported in seeds; thus implying that it is possible to modify lipid profiles according to the treatment used. According to the results of sucrose gradients and enzyme assays performed, it is proposed that cacao cells probably use the pentose phosphate pathway, mitochondria being the key organelle in the carbon flux for the synthesis of reductant power and fatty acid precursors. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  10. Cannabidiol Activates Neuronal Precursor Genes in Human Gingival Mesenchymal Stromal Cells.

    Science.gov (United States)

    Soundara Rajan, Thangavelu; Giacoppo, Sabrina; Scionti, Domenico; Diomede, Francesca; Grassi, Gianpaolo; Pollastro, Federica; Piattelli, Adriano; Bramanti, Placido; Mazzon, Emanuela; Trubiani, Oriana

    2017-06-01

    In the last years, mesenchymal stromal cells (MSCs) from oral tissues have received considerable interest in regenerative medicine since they can be obtained with minimal invasive procedure and exhibit immunomodulatory properties. This study was aimed to investigate whether in vitro pre-treatment of MSCs obtained from human gingiva (hGMSCs) with Cannabidiol (CBD), a cannabinoid component produced by the plant Cannabis sativa, may promote human gingiva derived MSCs to differentiate toward neuronal precursor cells. Specifically, we have treated the hGMSCs with CBD (5 µM) for 24 h in order to evaluate the expression of genes involved in cannabidiol signaling, cell proliferation, self-renewal and multipotency, and neural progenitor cells differentiation. Next generation sequencing (NGS) demonstrated that CBD activates genes associated with G protein coupled receptor signaling in hGMSCs. Genes involved in DNA replication, cell cycle, proliferation, and apoptosis were regulated. Moreover, genes associated with the biological process of neuronal progenitor cells (NCPs) proliferation, neuron differentiation, neurogenesis, and nervous system development were significantly modulated. From our results, we hypothesize that human gingiva-derived MSCs conditioned with CBD could represent a valid method for improving the hGMSCs phenotype and thus might be a potential therapeutic tool in the treatment of neurodegenerative diseases. J. Cell. Biochem. 118: 1531-1546, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  11. Differentiation of Human Embryonic Stem Cells to Regional Specific Neural Precursors in Chemically Defined Medium Conditions

    Science.gov (United States)

    Erceg, Slaven; Laínez, Sergio; Ronaghi, Mohammad; Stojkovic, Petra; Pérez-Aragó, Maria Amparo; Moreno-Manzano, Victoria; Moreno-Palanques, Rubén; Planells-Cases, Rosa; Stojkovic, Miodrag

    2008-01-01

    Background Human embryonic stem cells (hESC) provide a unique model to study early events in human development. The hESC-derived cells can potentially be used to replace or restore different tissues including neuronal that have been damaged by disease or injury. Methodology and Principal Findings The cells of two different hESC lines were converted to neural rosettes using adherent and chemically defined conditions. The progenitor cells were exposed to retinoic acid (RA) or to human recombinant basic fibroblast growth factor (bFGF) in the late phase of the rosette formation. Exposing the progenitor cells to RA suppressed differentiation to rostral forebrain dopamine neural lineage and promoted that of spinal neural tissue including motor neurons. The functional characteristics of these differentiated neuronal precursors under both, rostral (bFGF) and caudalizing (RA) signals were confirmed by patch clamp analysis. Conclusions/Significance These findings suggest that our differentiation protocol has the capacity to generate region-specific and electrophysiologically active neurons under in vitro conditions without embryoid body formation, co-culture with stromal cells and without presence of cells of mesodermal or endodermal lineages. PMID:18461168

  12. Differentiation of human embryonic stem cells to regional specific neural precursors in chemically defined medium conditions.

    Directory of Open Access Journals (Sweden)

    Slaven Erceg

    Full Text Available BACKGROUND: Human embryonic stem cells (hESC provide a unique model to study early events in human development. The hESC-derived cells can potentially be used to replace or restore different tissues including neuronal that have been damaged by disease or injury. METHODOLOGY AND PRINCIPAL FINDINGS: The cells of two different hESC lines were converted to neural rosettes using adherent and chemically defined conditions. The progenitor cells were exposed to retinoic acid (RA or to human recombinant basic fibroblast growth factor (bFGF in the late phase of the rosette formation. Exposing the progenitor cells to RA suppressed differentiation to rostral forebrain dopamine neural lineage and promoted that of spinal neural tissue including motor neurons. The functional characteristics of these differentiated neuronal precursors under both, rostral (bFGF and caudalizing (RA signals were confirmed by patch clamp analysis. CONCLUSIONS/SIGNIFICANCE: These findings suggest that our differentiation protocol has the capacity to generate region-specific and electrophysiologically active neurons under in vitro conditions without embryoid body formation, co-culture with stromal cells and without presence of cells of mesodermal or endodermal lineages.

  13. Multilayer solar cells based on CdTe grown from nitrate precursor

    Science.gov (United States)

    Salim, Hussein I.

    This thesis presents the research and development of low-cost multilayer graded-bandgap solar cells based on electrodeposited CdTe. The electronic quality layers used in this research are electrodeposited CdS and CdTe and chemical bath deposited (CBD) CdS. In the literature, the electrodeposition of CdS layers has been mainly reported using sodium thiosulphate (Na2S2O3), ammonium thiosulphate (NH4)2S2O3 and thioacetamide (C2H5NS) as the precursor for sulphur ions. The major disadvantages of these precursors are the precipitation of elemental S and CdS particles in the solution during growth which can affect the quality of the deposited thin films. Electrodeposition of the CdS from acidic and aqueous solutions using thiourea (SC(NH2)2) precursor has been able to overcome this disadvantage. No visible precipitations of elemental S or CdS particles were observed in the deposition electrolyte showing a stable bath during the growth.Also, in the literature, the CdTe thin films have been mainly electrodeposited using CdSO4 as the precursor for Cd ions whereas in this thesis the electrodeposition of the CdTe thin films were carried out comprehensively using cadmium nitrate Cd(NO3)2 as the precursor for Cd ions. Reports are scarce on the electrodeposition of CdS and CdTe thin films history using thiourea and nitrate precursors. Using these precursors, the CdS and CdTe have been successfully electrodeposited from aqueous solution on glass/fluorine-doped tin oxide (FTO) substrates, using simplified two-electrode system instead of the conventional three-electrode system. Also, the CBD-CdS thin films have been successfully grown from aqueous solution on glass/FTO substrates.The electrodeposited and chemical bath deposited materials were characterised for their structural, compositional, morphological, optical, electrical and defect properties using X-ray diffraction (XRD), Raman spectroscopy, energy dispersive X-ray diffraction (EDX), scanning electron microscopy (SEM), atomic

  14. Production of precursors for micro-concentrator solar cells by femtosecond laser-induced forward transfer

    Science.gov (United States)

    Andree, Stefan; Heidmann, Berit; Ringleb, Franziska; Eylers, Katharina; Bonse, Jörn; Boeck, Torsten; Schmid, Martina; Krüger, Jörg

    2017-10-01

    Single-pulse femtosecond laser-induced forward transfer (LIFT, 30 fs, 790 nm) is used to deposit micron-sized dots of copper and/or indium onto a molybdenum layer on glass. Such systems can serve as precursors for the bottom-up manufacturing of micro-concentrator solar cells based on copper-indium-gallium-diselenide. The influence of the thickness of the copper, indium, and combined copper-indium donor layers on the quality of the transferred dots was qualified by scanning electron microscopy, energy-dispersive X-ray analysis, and optical microscopy. The potential for manufacturing of a spatial arrangement adapted to the geometry of micro-lens arrays needed for micro-concentrator solar cells is demonstrated.

  15. Primary laryngeal manifestation in precursor T-cell acute lymphoblastic leukemia.

    Science.gov (United States)

    Wang, Lin; Ma, Yan; Chen, Bobin; Tang, Feng; Xu, Xiaoping; Lin, Guowei

    2015-02-01

    Primary involvement of the larynx in non-Hodgkin's lymphoma (NHL) is rare. Early symptoms are non-specific and thus, it is difficult to diagnose. In the present study, the case of a 52 year-old male with hoarseness due to diffuse T-cell lymphoma as the first manifestation of precursor T-cell acute lymphoblastic leukemia is presented. Subsequent to treatment with three cycles of the etoposide and cytosine arabinoside (EA) and one cycle of the EA+L-asp chemotherapy regimens, the patient achieved complete remission. A series of consolidation therapy courses were performed subsequently. At present, the patient remains disease-free, indicating that the treatment was effective. Primary involvement of the larynx in NHL is rare. Symptoms in the early stage are subtle and non-specific and thus, diagnosis is difficult to establish. This type of tumor requires special diagnostic and therapeutic attention.

  16. Different patterns of neuronal activity trigger distinct responses of oligodendrocyte precursor cells in the corpus callosum.

    Directory of Open Access Journals (Sweden)

    Balint Nagy

    2017-08-01

    Full Text Available In the developing and adult brain, oligodendrocyte precursor cells (OPCs are influenced by neuronal activity: they are involved in synaptic signaling with neurons, and their proliferation and differentiation into myelinating glia can be altered by transient changes in neuronal firing. An important question that has been unanswered is whether OPCs can discriminate different patterns of neuronal activity and respond to them in a distinct way. Here, we demonstrate in brain slices that the pattern of neuronal activity determines the functional changes triggered at synapses between axons and OPCs. Furthermore, we show that stimulation of the corpus callosum at different frequencies in vivo affects proliferation and differentiation of OPCs in a dissimilar way. Our findings suggest that neurons do not influence OPCs in "all-or-none" fashion but use their firing pattern to tune the response and behavior of these nonneuronal cells.

  17. Alignment of muscle precursor cells on the vertical edges of thick carbon nanotube films

    Energy Technology Data Exchange (ETDEWEB)

    Holt, Ian, E-mail: ian.holt@rjah.nhs.uk [Wolfson Centre for Inherited Neuromuscular Disease, RJAH Orthopaedic Hospital, Oswestry, Shropshire SY10 7AG (United Kingdom); Institute for Science and Technology in Medicine, Keele University, Keele, Staffordshire ST5 5BG (United Kingdom); Gestmann, Ingo, E-mail: Ingo.Gestmann@fei.com [FEI Europe B.V., Achtseweg Noord 5, 5651 Eindhoven (Netherlands); Wright, Andrew C., E-mail: a.wright@glyndwr.ac.uk [Advanced Materials Research Laboratory, Glyndwr University, Plas Coch, Mold Rd, Wrexham LL11 2AW (United Kingdom)

    2013-10-15

    The development of scaffolds and templates is an essential aspect of tissue engineering. We show that thick (> 0.5 mm) vertically aligned carbon nanotube films, made by chemical vapour deposition, can be used as biocompatible substrates for the directional alignment of mouse muscle cells where the cells grow on the exposed sides of the films. Ultra high resolution scanning electron microscopy reveals that the films themselves consist mostly of small diameter (10 nm) multi-wall carbon nanotubes of wavy morphology with some single wall carbon nanotubes. Our findings show that for this alignment to occur the nanotubes must be in pristine condition. Mechanical wiping of the films to create directional alignment is detrimental to directional bioactivity. Larger areas for study have been formed from a composite of multiply stacked narrow strips of nanotubes wipe-transferred onto elastomer supports. These composite substrates appear to show a useful degree of alignment of the cells. Highlights: • Highly oriented muscle precursor cells grown on edges of carbon nanotube pads • Mechanical treatment of nanotube pads highly deleterious to cell growth on edges • Larger areas created from wipe-transfer of narrow strips of nanotubes onto elastomer supports • Very high resolution SEM reveals clues to aligned cell growth.

  18. Mobilization of endothelial precursor cells: systemic vascular response to musculoskeletal trauma.

    LENUS (Irish Health Repository)

    Laing, A J

    2012-02-03

    Postnatal vasculogenesis, the process by which vascular committed bone marrow stem cells or endothelial precursor cells (EPC) migrate, differentiate, and incorporate into the nacent endothelium contributing to physiological and pathological neovascularization, has stimulated much interest. Its contribution to tumor nonvascularization, wound healing, and revascularization associated with skeletal and cardiac muscles ischaemia is established. We evaluated the mobilization of EPCs in response to musculoskeletal trauma. Blood from patients (n = 15) following AO type 42a1 closed diaphyseal tibial fractures was analyzed for CD34 and AC133 cell surface marker expression. Immunomagnetically enriched CD34+ mononuclear cell (MNC(CD34+)) populations were cultured and examined for phenotypic and functional vascular endothelial differentiation. Circulating MNC(CD34+) levels increased sevenfold by day 3 postinjury. Circulating MNC(AC133+) increased 2.5-fold. Enriched MNC(CD34+) populations from day 3 samples in culture exhibited cell cluster formation with sprouting spindles. These cells bound UEA-1 and incorporated fluorescent DiI-Ac-LDL intracellularily. Our findings suggest a systemic provascular response is initiated in response to musculoskeletal trauma. Its therapeutic manipulation may have implications for the potential enhancement of fracture healing.

  19. Differentiation of Oligodendrocyte Precursor Cells from Sox10-Venus Mice to Oligodendrocytes and Astrocytes.

    Science.gov (United States)

    Suzuki, Nobuharu; Sekimoto, Kaori; Hayashi, Chikako; Mabuchi, Yo; Nakamura, Tetsuya; Akazawa, Chihiro

    2017-10-26

    Oligodendrocytes are well known as myelin-forming cells in the central nervous system (CNS). However, detailed mechanisms of oligodendrocyte differentiation and myelination are poorly understood, particularly due to the difficulty of the purification of murine oligodendrocyte precursor cells (OPCs). We have recently established a transgenic mouse line that expresses a fluorescent protein Venus under the promoter of Sox10, whose expression is restricted to OPCs and oligodendrocytes in the CNS. Here, we have characterized Venus-positive cells from the Sox10-Venus mouse brain for analyzing oligodendrocyte differentiation. We first purified Venus-positive cells from the postnatal day 0-2 brain by flow cytometry. Most of the Venus-positive cells expressed NG2, an OPC marker. After induction of differentiation, an increased population of galactocerebroside-positive oligodendrocytes and decrease of OPCs were observed in the Venus-positive culture. Furthermore, a time-lapse analysis showed that Venus-positive oligodendrocytes dynamically changed their morphology with highly branched cell processes during differentiation. In addition, we found that Venus-positive OPCs were able to differentiate to type II astrocytes. In vivo, OPCs and oligodendrocytes express Venus, and some of astrocytes were positive for Venus in the ventral cortex. Taken together, the Sox10-Venus mouse system is useful for analyzing differentiation and multipotency of murine OPCs.

  20. Immunotargeting relapsed or refractory precursor B-cell acute lymphoblastic leukemia – role of blinatumomab

    Directory of Open Access Journals (Sweden)

    Queudeville M

    2017-07-01

    Full Text Available Manon Queudeville, Rupert Handgretinger, Martin Ebinger Department of Pediatric Hematology and Oncology, University Children’s Hospital, University of Tübingen, Tübingen, Germany Abstract: Patients with refractory or relapsed (R/R acute lymphoblastic leukemia (ALL have a dismal prognosis of around 5% long-term survival when treated with cytotoxic chemotherapy and allogenic stem cell transplantation. T-cell immunobased strategies open up new therapeutic perspectives. Blinatumomab is the first of a new class of antibody constructs that was labeled bispecific T-cell engager (BiTE: it consists of two single chain variable fragment connected with a flexible linker, one side binding CD3, the other CD19. The tight binding and the close proximity to the CD19-positive B-cells and leukemic cells leads to non-major histocompatibility complex-restricted T-cell activation, polyclonal T-cell expansion and direct target cell killing. Applied by continuous infusion, blinatumomab achieves morphological complete response rates ranging from 39% to 69% in R/R ALL patients (compared to 25% after second-line chemotherapy with prolonged overall survival (blinatumomab median overall survival, 7.7 months vs chemotherapy, 4.0 months. In comparison to conventional cytotoxic second-line protocols blinatumomab has a favorable safety profile. The main adverse event is related to the mode of action of blinatumomab: the induction of a cytokine-release syndrome that can be managed by interruption and/or the application of steroids or tocilizumab. Another typical complication is the occurrence of neurological side effects, such as seizures and encephalopathy. This neurotoxicity is reversible after application of steroids and/or withdrawal of blinatumomab. Blinatumomab has proven to be a powerful therapeutic option in R/R ALL patients both adult and pediatric because of its efficacy and limited toxicity. Keywords: R/R precursor B-cell ALL, blinatumomab, T-cell

  1. Gum hypertrophy - an unusual presenting feature in a case of precursor T-cell acute lymphoblastic leukemia

    Directory of Open Access Journals (Sweden)

    Lingappa Appaji

    2008-12-01

    Full Text Available Acute lymphoblastic leukemia/lymphoma, the malignant transformation of T-cell or B-cell precursors, is the most common diagnosis in pediatric oncology. Precursor T-cell acute lymphoblastic leukemia/lymphoma commonly affects adolescents, and is associated with mediastinal mass in over half of the cases, with early dissemination to bone marrow, gonads and the central nervous system. We present a rare case of precursor T-cell acute lymphoblastic leukemia/lymphoma with initial oral manifestation, presenting with the unusual features of gum hypertrophy and involvement of upper jaw and palate in a 10-year-old boy. This report discusses the clinical presentation, histopathologic and immunologic features, and diagnosis of this malignancy.

  2. Gum hypertrophy - an unusual presenting feature in a case of precursor T-cell acute lymphoblastic leukemia.

    Science.gov (United States)

    Premalata, Chennagiri Srinivasamurthy; Madhumati, Davanam Satyanarayana; Lakshmidevi, Vishweshwariah; Pradeep, Rudramurthy; Appaji, Lingappa; Mukherjee, Geetashree

    2008-12-05

    Acute lymphoblastic leukemia/lymphoma, the malignant transformation of T-cell or B-cell precursors, is the most common diagnosis in pediatric oncology. Precursor T-cell acute lymphoblastic leukemia/lymphoma commonly affects adolescents, and is associated with mediastinal mass in over half of the cases, with early dissemination to bone marrow, gonads and the central nervous system. We present a rare case of precursor T-cell acute lymphoblastic leukemia/lymphoma with initial oral manifestation, presenting with the unusual features of gum hypertrophy and involvement of upper jaw and palate in a 10-year-old boy. This report discusses the clinical presentation, histopathologic and immunologic features, and diagnosis of this malignancy.

  3. Human umbilical cord Wharton's jelly-derived oligodendrocyte precursor-like cells for axon and myelin sheath regeneration.

    Science.gov (United States)

    Chen, Hong; Zhang, Yan; Yang, Zhijun; Zhang, Hongtian

    2013-04-05

    Human umbilical mesenchymal stem cells from Wharton's jelly of the umbilical cord were induced to differentiate into oligodendrocyte precursor-like cells in vitro. Oligodendrocyte precursor cells were transplanted into contused rat spinal cords. Immunofluorescence double staining indicated that transplanted cells survived in injured spinal cord, and differentiated into mature and immature oligodendrocyte precursor cells. Biotinylated dextran amine tracing results showed that cell transplantation promoted a higher density of the corticospinal tract in the central and caudal parts of the injured spinal cord. Luxol fast blue and toluidine blue staining showed that the volume of residual myelin was significantly increased at 1 and 2 mm rostral and caudal to the lesion epicenter after cell transplantation. Furthermore, immunofluorescence staining verified that the newly regenerated myelin sheath was derived from the central nervous system. Basso, Beattie and Bresnahan testing showed an evident behavioral recovery. These results suggest that human umbilical mesenchymal stem cell-derived oligodendrocyte precursor cells promote the regeneration of spinal axons and myelin sheaths.

  4. Iron carrier proteins facilitate engraftment of allogeneic bone marrow and enduring hemopoietic chimerism in the lethally irradiated host

    Energy Technology Data Exchange (ETDEWEB)

    Pierpaoli, W.; Dall' Ara, A.; Yi, C.X.; Neri, P.; Santucci, A.; Choay, J. (Institute for Biomedical Research, Quartino (Switzerland))

    1991-04-15

    Cell-free supernatants of rabbit bone marrow were fractionated, separated, and purified by Ultrogel and Superose chromatography. A single fraction promoted engraftment of allogeneic bone marrow and enduring hemopoietic chimerism across the H-2 barrier in lethally irradiated mice. This 'bio-active' fraction, analyzed by reducing SDS-PAGE electrophoresis, and transblotted on PVDF membrane, and purified by reverse-phase HPLC and SDS-PAGE electrophoresis yielded a main prealbumin band that when examined for primary structure by Edman degradation, proved to be rabbit transferrin. This was also attested by highly specific precipitation of the prealbumin band with polyclonal antibodies to rabbit transferrin. Iron-saturated human transferrin, lactotransferrin, and egg transferrin (conalbumin) were assayed in irradiated C57BL/6 mice infused with bone marrow from histoincompatible BALB/c donors. Mice treated with iron-loaded transferrins survive and develop enduring allogeneic chimerism with no discernible signs of graft-versus-host disease. Iron carrier proteins thus provide an unique means of achieving successful engraftment of allogeneic bone marrow in immunologically hostile murine H-2 combinations.

  5. Sparing of extraocular muscle in aging and muscular dystrophies: A myogenic precursor cell hypothesis

    Energy Technology Data Exchange (ETDEWEB)

    Kallestad, Kristen M.; Hebert, Sadie L.; McDonald, Abby A.; Daniel, Mark L.; Cu, Sharon R.; McLoon, Linda K., E-mail: mcloo001@tc.umn.edu

    2011-04-01

    The extraocular muscles (EOM) are spared from pathology in aging and many forms of muscular dystrophy. Despite many studies, this sparing remains an enigma. The EOM have a distinct embryonic lineage compared to somite-derived muscles, and we have shown that they continuously remodel throughout life, maintaining a population of activated satellite cells even in aging. These data suggested the hypothesis that there is a population of myogenic precursor cells (mpcs) in EOM that is different from those in limb, with either elevated numbers of stem cells and/or mpcs with superior proliferative capacity compared to mpcs in limb. Using flow cytometry, EOM and limb muscle mononuclear cells were compared, and a number of differences were seen. Using two different cell isolation methods, EOM have significantly more mpcs per mg muscle than limb skeletal muscle. One specific subpopulation significantly increased in EOM compared to limb was positive for CD34 and negative for Sca-1, M-cadherin, CD31, and CD45. We named these the EOMCD34 cells. Similar percentages of EOMCD34 cells were present in both newborn EOM and limb muscle. They were retained in aged EOM, whereas the population decreased significantly in adult limb muscle and were extremely scarce in aged limb muscle. Most importantly, the percentage of EOMCD34 cells was elevated in the EOM from both the mdx and the mdx/utrophin{sup -/-} (DKO) mouse models of DMD and extremely scarce in the limb muscles of these mice. In vitro, the EOMCD34 cells had myogenic potential, forming myotubes in differentiation media. After determining a media better able to induce proliferation in these cells, a fusion index was calculated. The cells isolated from EOM had a 40% higher fusion index compared to the same cells isolated from limb muscle. The EOMCD34 cells were resistant to both oxidative stress and mechanical injury. These data support our hypothesis that the EOM may be spared in aging and in muscular dystrophies due to a

  6. Overexpression of amyloid precursor protein increases copper content in HEK293 cells

    Energy Technology Data Exchange (ETDEWEB)

    Suazo, Miriam; Hodar, Christian; Morgan, Carlos [INTA, Laboratorio de Bioinformatica y Expresion Genica, Universidad de Chile, El Libano 5524, Macul, Santiago (Chile); Cerpa, Waldo [Centro de Envejecimiento y Regeneracion (CARE), Centro de Regulacion Celular y Patologia ' Joaquin V. Luco' (CRCP), MIFAB, Departamento de Biologia Celular y Molecular, Facultad de Ciencias Biologicas, Pontificia Universidad Catolica de Chile, Santiago (Chile); Cambiazo, Veronica [INTA, Laboratorio de Bioinformatica y Expresion Genica, Universidad de Chile, El Libano 5524, Macul, Santiago (Chile); Millenium Nucleus CGC, Universidad de Chile (Chile); Inestrosa, Nibaldo C. [Centro de Envejecimiento y Regeneracion (CARE), Centro de Regulacion Celular y Patologia ' Joaquin V. Luco' (CRCP), MIFAB, Departamento de Biologia Celular y Molecular, Facultad de Ciencias Biologicas, Pontificia Universidad Catolica de Chile, Santiago (Chile); Gonzalez, Mauricio, E-mail: mgonzale@inta.cl [INTA, Laboratorio de Bioinformatica y Expresion Genica, Universidad de Chile, El Libano 5524, Macul, Santiago (Chile)

    2009-05-15

    Amyloid precursor protein (APP) is a transmembrane glycoprotein widely expressed in mammalian tissues and plays a central role in Alzheimer's disease. However, its physiological function remains elusive. Cu{sup 2+} binding and reduction activities have been described in the extracellular APP135-156 region, which might be relevant for cellular copper uptake and homeostasis. Here, we assessed Cu{sup 2+} reduction and {sup 64}Cu uptake in two human HEK293 cell lines overexpressing APP. Our results indicate that Cu{sup 2+} reduction increased and cells accumulated larger levels of copper, maintaining cell viability at supra-physiological levels of Cu{sup 2+} ions. Moreover, wild-type cells exposed to both Cu{sup 2+} ions and APP135-155 synthetic peptides increased copper reduction and uptake. Complementation of function studies in human APP751 transformed Fre1 defective Saccharomyces cerevisiae cells rescued low Cu{sup 2+} reductase activity and increased {sup 64}Cu uptake. We conclude that Cu{sup 2+} reduction activity of APP facilitates copper uptake and may represent an early step in cellular copper homeostasis.

  7. Macrophages improve survival, proliferation and migration of engrafted myogenic precursor cells into MDX skeletal muscle.

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    Pierre-François Lesault

    Full Text Available Transplantation of muscle precursor cells is of therapeutic interest for focal skeletal muscular diseases. However, major limitations of cell transplantation are the poor survival, expansion and migration of the injected cells. The massive and early death of transplanted myoblasts is not fully understood although several mechanisms have been suggested. Various attempts have been made to improve their survival or migration. Taking into account that muscle regeneration is associated with the presence of macrophages, which are helpful in repairing the muscle by both cleansing the debris and deliver trophic cues to myoblasts in a sequential way, we attempted in the present work to improve myoblast transplantation by coinjecting macrophages. The present data showed that in the 5 days following the transplantation, macrophages efficiently improved: i myoblast survival by limiting their massive death, ii myoblast expansion within the tissue and iii myoblast migration in the dystrophic muscle. This was confirmed by in vitro analyses showing that macrophages stimulated myoblast adhesion and migration. As a result, myoblast contribution to regenerating host myofibres was increased by macrophages one month after transplantation. Altogether, these data demonstrate that macrophages are beneficial during the early steps of myoblast transplantation into skeletal muscle, showing that coinjecting these stromal cells may be used as a helper to improve the efficiency of parenchymal cell engraftment.

  8. Residual embryonic cells as precursors of a Barrett's-like metaplasia.

    Science.gov (United States)

    Wang, Xia; Ouyang, Hong; Yamamoto, Yusuke; Kumar, Pooja Ashok; Wei, Tay Seok; Dagher, Rania; Vincent, Matthew; Lu, Xin; Bellizzi, Andrew M; Ho, Khek Yu; Crum, Christopher P; Xian, Wa; McKeon, Frank

    2011-06-24

    Barrett's esophagus is an intestine-like metaplasia and precursor of esophageal adenocarcinoma. Triggered by gastroesophageal reflux disease, the origin of this metaplasia remains unknown. p63-deficient mice, which lack squamous epithelia, may model acid-reflux damage. We show here that p63 null embryos rapidly develop intestine-like metaplasia with gene expression profiles similar to Barrett's metaplasia. We track its source to a unique embryonic epithelium that is normally undermined and replaced by p63-expressing cells. Significantly, we show that a discrete population of these embryonic cells persists in adult mice and humans at the squamocolumnar junction, the source of Barrett's metaplasia. We show that upon programmed damage to the squamous epithelium, these embryonic cells migrate toward adjacent, specialized squamous cells in a process that may recapitulate early Barrett's. Our findings suggest that certain precancerous lesions, such as Barrett's, initiate not from genetic alterations but from competitive interactions between cell lineages driven by opportunity. Copyright © 2011 Elsevier Inc. All rights reserved.

  9. Human Neural Precursor Cells Promote Neurologic Recovery in a Viral Model of Multiple Sclerosis

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    Lu Chen

    2014-06-01

    Full Text Available Using a viral model of the demyelinating disease multiple sclerosis (MS, we show that intraspinal transplantation of human embryonic stem cell-derived neural precursor cells (hNPCs results in sustained clinical recovery, although hNPCs were not detectable beyond day 8 posttransplantation. Improved motor skills were associated with a reduction in neuroinflammation, decreased demyelination, and enhanced remyelination. Evidence indicates that the reduced neuroinflammation is correlated with an increased number of CD4+CD25+FOXP3+ regulatory T cells (Tregs within the spinal cords. Coculture of hNPCs with activated T cells resulted in reduced T cell proliferation and increased Treg numbers. The hNPCs acted, in part, through secretion of TGF-β1 and TGF-β2. These findings indicate that the transient presence of hNPCs transplanted in an animal model of MS has powerful immunomodulatory effects and mediates recovery. Further investigation of the restorative effects of hNPC transplantation may aid in the development of clinically relevant MS treatments.

  10. Hippocalcin Is Required for Astrocytic Differentiation through Activation of Stat3 in Hippocampal Neural Precursor Cells.

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    Min-Jeong Kang

    2016-10-01

    Full Text Available Hippocalcin (Hpca is a neuronal calcium sensor protein expressed in the mammalian brain. However, its function in neural stem/precursor cells has not yet been studied. Here, we clarify the function of Hpca in astrocytic differentiation in hippocampal neural precursor cells (HNPCs. When we overexpressed Hpca in HNPCs in the presence or absence of bFGF, expression levels of nerve-growth factors such as neurotrophin-3 (NT-3, neurotrophin-4/5 (NT-4/5 and brain-derived neurotrophic factor (BDNF, together with the proneural basic helix loop helix (bHLH transcription factors neuroD and neurogenin 1 (ngn1, increased significantly. In addition, there was an increase in the number of cells expressing glial fibrillary acidic protein (GFAP, an astrocyte marker, and in dendrite outgrowth, indicating astrocytic differentiation of the HNPCs. Downregulation of Hpca by transfection with Hpca siRNA reduced expression of NT-3, NT-4/5, BDNF, neuroD and ngn1 as well as levels of GFAP protein. Furthermore, overexpression of Hpca increased the phosphorylation of STAT3 (Ser727, and this effect was abolished by treatment with a STAT3 inhibitor (S3I-201, suggesting that STAT3 (Ser727 activation is involved in Hpca-mediated astrocytic differentiation. As expected, treatment with Stat3 siRNA or STAT3 inhibitor caused a complete inhibition of astrogliogenesis induced by Hpca overexpression. Taken together, this is the first report to show that Hpca, acting through Stat3, has an important role in the expression of neurotrophins and proneural bHLH transcription factors, and that it is an essential regulator of astrocytic differentiation and dendrite outgrowth in HNPCs.

  11. Long-term impact of radiation on the stem cell and oligodendrocyte precursors in the brain.

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    Georgia Panagiotakos

    Full Text Available The cellular basis of long term radiation damage in the brain is not fully understood.We administered a dose of 25Gy to adult rat brains while shielding the olfactory bulbs. Quantitative analyses were serially performed on different brain regions over 15 months. Our data reveal an immediate and permanent suppression of SVZ proliferation and neurogenesis. The olfactory bulb demonstrates a transient but remarkable SVZ-independent ability for compensation and maintenance of the calretinin interneuron population. The oligodendrocyte compartment exhibits a complex pattern of limited proliferation of NG2 progenitors but steady loss of the oligodendroglial antigen O4. As of nine months post radiation, diffuse demyelination starts in all irradiated brains. Counts of capillary segments and length demonstrate significant loss one day post radiation but swift and persistent recovery of the vasculature up to 15 months post XRT. MRI imaging confirms loss of volume of the corpus callosum and early signs of demyelination at 12 months. Ultrastructural analysis demonstrates progressive degradation of myelin sheaths with axonal preservation. Areas of focal necrosis appear beyond 15 months and are preceded by widespread demyelination. Human white matter specimens obtained post-radiation confirm early loss of oligodendrocyte progenitors and delayed onset of myelin sheath fragmentation with preserved capillaries.This study demonstrates that long term radiation injury is associated with irreversible damage to the neural stem cell compartment in the rodent SVZ and loss of oligodendrocyte precursor cells in both rodent and human brain. Delayed onset demyelination precedes focal necrosis and is likely due to the loss of oligodendrocyte precursors and the inability of the stem cell compartment to compensate for this loss.

  12. Neural precursor cells derived from induced pluripotent stem cells exhibit reduced susceptibility to infection with a neurotropic coronavirus.

    Science.gov (United States)

    Mangale, Vrushali; Marro, Brett S; Plaisted, Warren C; Walsh, Craig M; Lane, Thomas E

    2017-11-01

    The present study examines the susceptibility of mouse induced pluripotent stem cell-derived neural precursor cells (iPSC-NPCs) to infection with the neurotropic JHM strain of mouse hepatitis virus (JHMV). Similar to NPCs derived from striatum of day 1 postnatal GFP-transgenic mice (GFP-NPCs), iPSC-derived NPCs (iPSC-NPCs) are able to differentiate into terminal neural cell types and express MHC class I and II in response to IFN-γ treatment. However, in contrast to postnatally-derived NPCs, iPSC-NPCs express low levels of carcinoembryonic antigen-cell adhesion molecule 1a (CEACAM1a), the surface receptor for JHMV, and are less susceptible to infection and virus-induced cytopathic effects. The relevance of this in terms of therapeutic application of NPCs resistant to viral infection is discussed. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Lymphocyte formation, life span, fate, and potential for repopulating hemopoietic tissues of irradiated animals. Progress report

    Energy Technology Data Exchange (ETDEWEB)

    1975-04-15

    Progress is reported on studies of lymphocyte formation, life span, fate, and potential for repopulating hemopoietic tissues of irradiated animals. The labeling of lymphocytes with /sup 3/H-deoxycytidine (/sup 3/H-CdR) gave good results when compared with /sup 3/H-thymidine (/sup 3/H-TdR) labeling. Changes in pyrimidine metabolism during lymphopoiesis were studied by culturing rat thoracic duct lymphocytes on syngeneic fibroblast monolayers in the continued presence of PHA. A list is included of papers published and in print that report the results of studies in detail. (CH)

  14. Different mechanisms must be considered to explain the increase in hippocampal neural precursor cell proliferation by physical activity

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    Rupert W Overall

    2016-08-01

    Full Text Available The number of proliferating neural precursor cells in the adult hippocampus is strongly increased by physical activity. The mechanisms through which this behavioral stimulus induces cell proliferation, however, are not yet understood. In fact, even the mode of proliferation of the stem and progenitor cells is not exactly known. Evidence exists for several mechanisms including cell cycle shortening, reduced cell death and stem cell recruitment, but as yet no model can account for all observations. An appreciation of how the cells proliferate, however, is crucial to our ability to model the neurogenic process and predict its behavior in response to pro-neurogenic stimuli. In a recent study, we addressed modulation of the cell cycle length as one possible mode of regulation of precursor cell proliferation in running mice. Our results indicated that the observed increase in number of proliferating cells could not be explained through a shortening of the cell cycle. We must therefore consider other mechanisms by which physical activity leads to enhanced precursor cell proliferation. Here we review the evidence for and against several different hypotheses and discuss the implications for future research in the field.

  15. Intrinsic differences in adipocyte precursor cells from different white fat depots

    DEFF Research Database (Denmark)

    Macotela, Yazmín; Emanuelli, Brice; Mori, Marcelo A

    2012-01-01

    Obesity and body fat distribution are important risk factors for the development of type 2 diabetes and metabolic syndrome. Evidence has accumulated that this risk is related to intrinsic differences in behavior of adipocytes in different fat depots. In the current study, we demonstrate that adip......Obesity and body fat distribution are important risk factors for the development of type 2 diabetes and metabolic syndrome. Evidence has accumulated that this risk is related to intrinsic differences in behavior of adipocytes in different fat depots. In the current study, we demonstrate...... that adipocyte precursor cells (APCs) isolated from visceral and subcutaneous white adipose depots of mice have distinct patterns of gene expression, differentiation potential, and response to environmental and genetic influences. APCs derived from subcutaneous fat differentiate well in the presence of classical...

  16. Differentially activated macrophages orchestrate myogenic precursor cell fate during human skeletal muscle regeneration

    DEFF Research Database (Denmark)

    Saclier, Marielle; Yacoub-Youssef, Houda; Mackey, Abigail

    2013-01-01

    , we explored both in vitro and in vivo, in human, the interactions of differentially activated MPs with myogenic precursor cells (MPCs) during adult myogenesis and skeletal muscle regeneration. We showed in vitro that through the differential secretion of cytokines and growth factors, proinflammatory...... MPs inhibited MPC fusion while anti-inflammatory MPs strongly promoted MPC differentiation by increasing their commitment into differentiated myocytes and the formation of mature myotubes. Furthermore, the in vivo time course of expression of myogenic and MP markers was studied in regenerating human...... healthy muscle after damage. We observed that regenerating areas containing proliferating MPCs were preferentially associated with MPs expressing proinflammatory markers. In the same muscle, regenerating areas containing differentiating myogenin-positive MPCs were preferentially coupled to MPs harboring...

  17. Bioproduction of Antibody-Drug Conjugate Payload Precursors by Engineered Cell Factories.

    Science.gov (United States)

    Wang, Jie; Xiao, Han; Qian, Zhi-Gang; Zhong, Jian-Jiang

    2017-05-01

    Antibody-drug conjugates (ADCs), which combine the exquisite specificity of antibodies with the cell-killing ability of cytotoxic drug payloads, have emerged as an attractive means for treating cancers. All (pre)clinical ADCs employ biosynthesized cytotoxins as their ADC payload precursors (APPs). The cost-effective bioproduction of APPs is receiving great interest from both academia and industry. Given the lack of systematic overviews of the topic, we provide the current status of APPs and focus on their state-of-the-art bioproduction strategies, illustrated with typical examples and critical analyses. Challenges in further enhancing the bioproduction efficiency of APPs and other cytotoxins are also discussed. This research has implications for bioprocess and metabolic engineering, systems and synthetic biology, and biopharmaceutical drug discovery, development, and industrialization. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Dual-Source Precursor Approach for Highly Efficient Inverted Planar Heterojunction Perovskite Solar Cells.

    Science.gov (United States)

    Luo, Deying; Zhao, Lichen; Wu, Jiang; Hu, Qin; Zhang, Yifei; Xu, Zhaojian; Liu, Yi; Liu, Tanghao; Chen, Ke; Yang, Wenqiang; Zhang, Wei; Zhu, Rui; Gong, Qihuang

    2017-05-01

    The highest efficiencies reported for perovskite solar cells so far have been obtained mainly with methylammonium and formamidinium mixed cations. Currently, high-quality mixed-cation perovskite thin films are normally made by use of antisolvent protocols. However, the widely used "antisolvent"-assisted fabrication route suffers from challenges such as poor device reproducibility, toxic and hazardous organic solvent, and incompatibility with scalable fabrication process. Here, a simple dual-source precursor approach is developed to fabricate high-quality and mirror-like mixed-cation perovskite thin films without involving additional antisolvent process. By integrating the perovskite films into the planar heterojunction solar cells, a power conversion efficiency of 20.15% is achieved with negligible current density-voltage hysteresis. A stabilized power output approaching 20% is obtained at the maximum power point. These results shed light on fabricating highly efficient perovskite solar cells via a simple process, and pave the way for solar cell fabrication via scalable methods in the near future. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. JAK2 aberrations in childhood B-cell precursor acute lymphoblastic leukemia

    Science.gov (United States)

    de Goffau-Nobel, Willemieke; Hoogkamer, Alex Q.; Boer, Judith M.; Boeree, Aurélie; van de Ven, Cesca; Koudijs, Marco J.; Besselink, Nicolle J.M.; de Groot-Kruseman, Hester A.; Zwaan, Christian Michel; Horstmann, Martin A.; Pieters, Rob; den Boer, Monique L.

    2017-01-01

    JAK2 abnormalities may serve as target for precision medicines in pediatric B-cell precursor acute lymphoblastic leukemia (BCP-ALL). In the current study we performed a screening for JAK2 mutations and translocations, analyzed the clinical outcome and studied the efficacy of two JAK inhibitors in primary BCP-ALL cells. Importantly, we identify a number of limitations of JAK inhibitor therapy. JAK2 mutations mainly occurred in the poor prognostic subtypes BCR-ABL1-like and non- BCR-ABL1-like B-other (negative for sentinel cytogenetic lesions). JAK2 translocations were restricted to BCR-ABL1-like cases. Momelotinib and ruxolitinib were cytotoxic in both JAK2 translocated and JAK2 mutated cells, although efficacy in JAK2 mutated cells highly depended on cytokine receptor activation by TSLP. However, our data also suggest that the effect of JAK inhibition may be compromised by mutations in alternative survival pathways and microenvironment-induced resistance. Furthermore, inhibitors induced accumulation of phosphorylated JAK2Y1007, which resulted in a profound re-activation of JAK2 signaling upon release of the inhibitors. This preclinical evidence implies that further optimization and evaluation of JAK inhibitor treatment is necessary prior to its clinical integration in pediatric BCP-ALL. PMID:29163799

  20. Altered neutrophil immunophenotypes in childhood B-cell precursor acute lymphoblastic leukemia

    Science.gov (United States)

    Oliveira, Elen; Bacelar, Thiago S.; Ciudad, Juana; Ribeiro, Maria Cecília M.; Garcia, Daniela R.N.; Sedek, Lukasz; Maia, Simone F.; Aranha, Daniel B.; Machado, Indyara C.; Ikeda, Arissa; Baglioli, Bianca F.; Lopez-Duarte, Nathalia; Teixeira, Lisandra A. C.; Szczepanski, Tomasz; Silva, Maria Luiza M.; Land, Marcelo G.P.

    2016-01-01

    An increasing number of evidences suggest a genetic predisposition in acute lymphoblastic leukemia (ALL) that might favor the occurrence of the driver genetic alterations. Such genetic background might also translate into phenotypic alterations of residual hematopoietic cells. Whether such phenotypic alterations are present in bone marrow (BM) cells from childhood B-cell precursor (BCP)-ALL remains to be investigated. Here we analyzed the immunophenotypic profile of BM and peripheral blood (PB) maturing/matured neutrophils from 118 children with BCP-ALL and their relationship with the features of the disease. Our results showed altered neutrophil phenotypes in most (77%) BCP-ALL cases. The most frequently altered marker was CD10 (53%), followed by CD33 (34%), CD13 (15%), CD15/CD65 (10%) and CD123 (7%). Of note, patients with altered neutrophil phenotypes had younger age (p = 0.03) and lower percentages of BM maturing neutrophils (p = 0.004) together with greater BM lymphocyte (p = 0.04), and mature B-cell (p = 0.03) counts. No significant association was found between an altered neutrophil phenotype and other disease features. These findings point out the potential existence of an altered residual hematopoiesis in most childhood BCP-ALL cases. PMID:27028865

  1. NFIL3 Orchestrates the Emergence of Common Helper Innate Lymphoid Cell Precursors

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    Wei Xu

    2015-03-01

    Full Text Available Innate lymphoid cells (ILCs are a family of effectors that originate from a common innate lymphoid cell progenitor. However, the transcriptional program that sets the identity of the ILC lineage remains elusive. Here, we show that NFIL3 is a critical regulator of the common helper-like innate lymphoid cell progenitor (CHILP. Cell-intrinsic Nfil3 ablation led to variably impaired development of fetal and adult ILC subsets. Conditional gene targeting demonstrated that NFIL3 exerted its function prior to ILC subset commitment. Accordingly, NFIL3 ablation resulted in loss of ID2+ CHILP and PLZF+ ILC progenitors. Nfil3 expression in lymphoid progenitors was under the control of the mesenchyme-derived hematopoietin IL-7, and NFIL3 exerted its function via direct Id2 regulation in the CHILP. Moreover, ectopic Id2 expression in Nfil3-null precursors rescued defective ILC lineage development in vivo. Our data establish NFIL3 as a key regulator of common helper-like ILC progenitors as they emerge during early lymphopoiesis.

  2. Nanofiber-mediated microRNA delivery to enhance differentiation and maturation of oligodendroglial precursor cells.

    Science.gov (United States)

    Diao, Hua Jia; Low, Wei Ching; Milbreta, Ulla; Lu, Q Richard; Chew, Sing Yian

    2015-06-28

    Remyelination in the central nervous system (CNS) is critical in the treatment of many neural pathological conditions. Unfortunately, the ability to direct and enhance oligodendrocyte (OL) differentiation and maturation remains limited. It is known that microenvironmental signals, such as substrate topography and biochemical signaling, regulate cell fate commitment. Therefore, in this study, we developed a nanofiber-mediated microRNA (miR) delivery method to control oligodendroglial precursor cell (OPC) differentiation through a combination of fiber topography and gene silencing. Using poly(ε-caprolactone) nanofibers, efficient knockdown of OL differentiation inhibitory regulators were achieved by either nanofiber alone (20-40%, pnanofiber topography enhanced OPC differentiation by inducing 2-fold increase in RIP(+) cells (pnanofiber-mediated delivery of miR-219 and miR-338 promoted OL maturation by increasing the number of MBP(+) cells significantly (pnanofibers in providing topographical cues and microRNA reverse transfection to direct OPC differentiation. Such scaffolds may find useful applications in directing oligodendrocyte differentiation and myelination for treatment of CNS pathological conditions that require remyelination. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. The influence of retinoic acid on the human oligodendrocyte precursor cells by RNA-sequencing

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    Sun young Kim

    2017-03-01

    Full Text Available Retinoic acid (RA, a metabolite of vitamin A, has been found to influence regeneration in the adult central nervous system (CNS. There may be an effect of RA in the recovery/repair in multiple sclerosis (MS, an autoimmune and neurodegenerative disease of the CNS. We hypothesized that RA is a regulator of the further differentiation of oligodendrocyte precursor cells (OPCs – cells key to the remyelination process in MS. We conducted studies utilizing RNA-sequencing in human embryonic stem cell (hESC-derived neural stem cells (NSCs and OPCs so as to understand the role of transcriptional regulators during transition from both ESCs to NSCs and NSCs to OPCs. We identified that expression of retinoic acid receptors β and γ (RARβ and RARγ was significantly increased following the transition from NSCs to OPCs. We also demonstrated that long term in vitro culture of hESC-derived OPC with different isoforms of RA led to the significant up-regulation of two known transcriptional inhibitors of oligodendrocyte differentiation: Hes5 following prolonged treatment with all-trans-RA, 9-cis RA and 13-cis RA; and Id4 following treatment with 13cisRA. These results suggest that long term exposure to certain RA isoforms may impact the continued differentiation of this population.

  4. Precursor B-cell acute lymphoblastic leukemia presenting as obstructive jaundice: a case report

    Directory of Open Access Journals (Sweden)

    Awasum Michael

    2011-07-01

    Full Text Available Abstract Introduction Acute leukemias very rarely present with jaundice. Herein we report a case of precursor B-cell acute lymphoblastic leukemia that presented with jaundice in an adult. Case presentation A 44-year-old Hispanic man presented with right upper quadrant abdominal pain and jaundice. His initial blood work revealed pancytopenia and hyperbilirubinemia. Direct bilirubin was more than 50% of the total. His imaging studies were unremarkable except for hepatomegaly. All blood screening tests for various hepatocellular etiologies were normal. A diagnosis of precursor B-cell acute lymphoblastic leukemia was made upon liver biopsy. It also showed lymphocytic infiltration of the hepatic parenchyma leading to bile stasis. The diagnosis was subsequently confirmed upon bone marrow biopsy. The patient was treated with a hyperfractionated cyclophosphamide/vincristine/doxorubicin/dexamethasone regimen. Conclusion Acute lymphoblastic leukemia should be one of the differential diagnoses that should be considered when initial work-up for jaundice is inconclusive. Some cases of acute lymphoblastic leukemia have been reported in both adults and children to have presented with the initial manifestation of jaundice, but only a few had no radiographic evidence of biliary obstruction. Such presentation can pose a serious diagnostic dilemma for clinicians. This manuscript attempts to highlight it. Moreover, we believe that if acute lymphoblastic leukemia presentations similar to this case continue to be reported in adults or children, a specific immunophenotypic expression and cytogenetic abnormality may be found to be associated with hepatic infiltration by leukemia. This may substantially contribute to the further understanding of the pathophysiology of this hematologic disease.

  5. GDNF facilitates differentiation of the adult dentate gyrus-derived neural precursor cells into astrocytes via STAT3

    Energy Technology Data Exchange (ETDEWEB)

    Boku, Shuken, E-mail: shuboku@med.hokudai.ac.jp [Department of Psychiatry, Hokkaido University Graduate School of Medicine, Sapporo (Japan); Nakagawa, Shin [Department of Psychiatry, Hokkaido University Graduate School of Medicine, Sapporo (Japan); Takamura, Naoki [Pharmaceutical Laboratories, Dainippon Sumitomo Pharma Co. Ltd., Osaka (Japan); Kato, Akiko [Department of Psychiatry, Hokkaido University Graduate School of Medicine, Sapporo (Japan); Takebayashi, Minoru [Department of Psychiatry, National Hospital Organization Kure Medical Center, Kure (Japan); Hisaoka-Nakashima, Kazue [Department of Pharmacology, Hiroshima University Graduate School of Biomedical Sciences, Hiroshima (Japan); Omiya, Yuki; Inoue, Takeshi; Kusumi, Ichiro [Department of Psychiatry, Hokkaido University Graduate School of Medicine, Sapporo (Japan)

    2013-05-17

    Highlights: •GDNF has no effect on ADP proliferation and apoptosis. •GDNF increases ADP differentiation into astrocyte. •A specific inhibitor of STAT3 decreases the astrogliogenic effect of GDNF. •STAT3 knockdown by lentiviral shRNA vector also decreases the astrogliogenic effect of GDNF. •GDNF increases the phosphorylation of STAT3. -- Abstract: While the pro-neurogenic actions of antidepressants in the adult hippocampal dentate gyrus (DG) are thought to be one of the mechanisms through which antidepressants exert their therapeutic actions, antidepressants do not increase proliferation of neural precursor cells derived from the adult DG. Because previous studies showed that antidepressants increase the expression and secretion of glial cell line-derived neurotrophic factor (GDNF) in C6 glioma cells derived from rat astrocytes and GDNF increases neurogenesis in adult DG in vivo, we investigated the effects of GDNF on the proliferation, differentiation and apoptosis of cultured neural precursor cells derived from the adult DG. Data showed that GDNF facilitated the differentiation of neural precursor cells into astrocytes but had no effect on their proliferation or apoptosis. Moreover, GDNF increased the phosphorylation of STAT3, and both a specific inhibitor of STAT3 and lentiviral shRNA for STAT3 decreased their differentiation into astrocytes. Taken together, our findings suggest that GDNF facilitates astrogliogenesis from neural precursor cells in adult DG through activating STAT3 and that this action might indirectly affect neurogenesis.

  6. Epicardial HIF signaling regulates vascular precursor cell invasion into the myocardium

    Science.gov (United States)

    Tao, Jiayi; Doughman, Yongqiu; Yang, Ke; Ramirez-Bergeron, Diana; Watanabe, Michiko

    2013-01-01

    During cardiogenesis, a subset of epicardial cells undergoes epithelial-mesenchymal-transition (EMT) and the resulting epicardial derived cells (EPDCs) contribute to the formation of coronary vessels. Our previous data showed hypoxia inducible factor-1α (HIF-1α) expression at specific sites within the epicardium and support a link between hypoxia inducible factors (HIFs) and the patterning of coronary vasculogenesis. To better understand the autocrine role of HIFs in the epicardium, we transduced adenovirus mediated expression of constitutively active HIF-1α (AdcaHIF1α) into the embryonic avian epicardium where the vascular precursors reside. We found that introducing caHIF1α into the epicardial mesothelium prevented EPDCs from proper migration into the myocardium. In vitro collagen gel assays and ex vivo organ culture data further confirmed that infection with AdcaHIF1α impaired the ability of EPDCs to invade. However, the proficiency of epicardial cells to undergo EMT was enhanced while the movement of EPDCs within the sub-epicardium and their differentiation into smooth muscle cells were not disrupted by caHIF1α. We also showed that the transcript level of Flt-1 (VEGFR1), which can act as a VEGF signaling inhibitor, increased several fold after introducing caHIF1α into epicardial cells. Blocking the activation of the VEGF pathway in epicardial cells recapitulated the inhibition of EPDC invasion. These results suggest that caHIF1α mediated up-regulation of Flt-1, which blocks the activation of the VEGF pathway, is responsible for the inhibition of EPDC myocardial migration. In conclusion, our studies demonstrate that HIF signaling potentially regulates the degree of epicardial EMT and the extent of EPDC migration into the myocardium, both of which are likely critical in patterning the coronary vasculature during early cardiac vasculogenesis. These signals could explain why the larger coronaries appear and remain on the epicardial surface. PMID:23384563

  7. Effect of oxygen tension on bioenergetics and proteostasis in young and old myoblast precursor cells

    Directory of Open Access Journals (Sweden)

    M. Konigsberg

    2013-01-01

    Full Text Available In the majority of studies using primary cultures of myoblasts, the cells are maintained at ambient oxygen tension (21% O2, despite the fact that physiological O2 at the tissue level in vivo is much lower (~1–5% O2. We hypothesized that the cellular response in presence of high oxygen concentration might be particularly important in studies comparing energetic function or oxidative stress in cells isolated from young versus old animals. To test this, we asked whether oxygen tension plays a role in mitochondrial bioenergetics (oxygen consumption, glycolysis and fatty acid oxidation or oxidative damage to proteins (protein disulfides, carbonyls and aggregates in myoblast precursor cells (MPCs isolated from young (3–4 m and old (29–30 m C57BL/6 mice. MPCs were grown under physiological (3% or ambient (21% O2 for two weeks prior to exposure to an acute oxidative insult (H2O2. Our results show significantly higher basal mitochondrial respiration in young versus old MPCs, an increase in basal respiration in young MPCs maintained at 3% O2 compared to cells maintained at 21% O2, and a shift toward glycolytic metabolism in old MPCs grown at 21% O2. H2O2 treatment significantly reduced respiration in old MPCs grown at 3% O2 but did not further repress respiration at 21% O2 in old MPCs. Oxidative damage to protein was higher in cells maintained at 21% O2 and increased in response to H2O2 in old MPCs. These data underscore the importance of understanding the effect of ambient oxygen tension in cell culture studies, in particular studies measuring oxidative damage and mitochondrial function.

  8. Highly efficient differentiation of neural precursors from human embryonic stem cells and benefits of transplantation after ischemic stroke in mice.

    Science.gov (United States)

    Drury-Stewart, Danielle; Song, Mingke; Mohamad, Osama; Guo, Ying; Gu, Xiaohuan; Chen, Dongdong; Wei, Ling

    2013-08-08

    Ischemic stroke is a leading cause of death and disability, but treatment options are severely limited. Cell therapy offers an attractive strategy for regenerating lost tissues and enhancing the endogenous healing process. In this study, we investigated the use of human embryonic stem cell-derived neural precursors as a cell therapy in a murine stroke model. Neural precursors were derived from human embryonic stem cells by using a fully adherent SMAD inhibition protocol employing small molecules. The efficiency of neural induction and the ability of these cells to further differentiate into neurons were assessed by using immunocytochemistry. Whole-cell patch-clamp recording was used to demonstrate the electrophysiological activity of human embryonic stem cell-derived neurons. Neural precursors were transplanted into the core and penumbra regions of a focal ischemic stroke in the barrel cortex of mice. Animals received injections of bromodeoxyuridine to track regeneration. Neural differentiation of the transplanted cells and regenerative markers were measured by using immunohistochemistry. The adhesive removal test was used to determine functional improvement after stroke and intervention. After 11 days of neural induction by using the small-molecule protocol, over 95% of human embryonic stem-derived cells expressed at least one neural marker. Further in vitro differentiation yielded cells that stained for mature neuronal markers and exhibited high-amplitude, repetitive action potentials in response to depolarization. Neuronal differentiation also occurred after transplantation into the ischemic cortex. A greater level of bromodeoxyuridine co-localization with neurons was observed in the penumbra region of animals receiving cell transplantation. Transplantation also improved sensory recovery in transplant animals over that in control animals. Human embryonic stem cell-derived neural precursors derived by using a highly efficient small-molecule SMAD inhibition

  9. Sequential generation of olfactory bulb glutamatergic neurons by Neurog2-expressing precursor cells

    Directory of Open Access Journals (Sweden)

    Brill Monika S

    2011-04-01

    Full Text Available Abstract Background While the diversity and spatio-temporal origin of olfactory bulb (OB GABAergic interneurons has been studied in detail, much less is known about the subtypes of glutamatergic OB interneurons. Results We studied the temporal generation and diversity of Neurog2-positive precursor progeny using an inducible genetic fate mapping approach. We show that all subtypes of glutamatergic neurons derive from Neurog2 positive progenitors during development of the OB. Projection neurons, that is, mitral and tufted cells, are produced at early embryonic stages, while a heterogeneous population of glutamatergic juxtaglomerular neurons are generated at later embryonic as well as at perinatal stages. While most juxtaglomerular neurons express the T-Box protein Tbr2, those generated later also express Tbr1. Based on morphological features, these juxtaglomerular cells can be identified as tufted interneurons and short axon cells, respectively. Finally, targeted electroporation experiments provide evidence that while the majority of OB glutamatergic neurons are generated from intrabulbar progenitors, a small portion of them originate from extrabulbar regions at perinatal ages. Conclusions We provide the first comprehensive analysis of the temporal and spatial generation of OB glutamatergic neurons and identify distinct populations of juxtaglomerular interneurons that differ in their antigenic properties and time of origin.

  10. The genetic basis of early T-cell precursor acute lymphoblastic leukaemia

    Science.gov (United States)

    Zhang, Jinghui; Ding, Li; Holmfeldt, Linda; Wu, Gang; Heatley, Sue L.; Payne-Turner, Debbie; Easton, John; Chen, Xiang; Wang, Jianmin; Rusch, Michael; Lu, Charles; Chen, Shann-Ching; Wei, Lei; Collins-Underwood, J. Racquel; Ma, Jing; Roberts, Kathryn G.; Pounds, Stanley B.; Ulyanov, Anatoly; Becksfort, Jared; Gupta, Pankaj; Huether, Robert; Kriwacki, Richard W.; Parker, Matthew; McGoldrick, Daniel J.; Zhao, David; Alford, Daniel; Espy, Stephen; Bobba, Kiran Chand; Song, Guangchun; Pei, Deqing; Cheng, Cheng; Roberts, Stefan; Barbato, Michael I.; Campana, Dario; Coustan-Smith, Elaine; Shurtleff, Sheila A.; Raimondi, Susana C.; Kleppe, Maria; Cools, Jan; Shimano, Kristin A.; Hermiston, Michelle L.; Doulatov, Sergei; Eppert, Kolja; Laurenti, Elisa; Notta, Faiyaz; Dick, John E.; Basso, Giuseppe; Hunger, Stephen P.; Loh, Mignon L.; Devidas, Meenakshi; Wood, Brent; Winter, Stuart; Dunsmore, Kimberley P.; Fulton, Robert S.; Fulton, Lucinda L.; Hong, Xin; Harris, Christopher C.; Dooling, David J.; Ochoa, Kerri; Johnson, Kimberly J.; Obenauer, John C.; Evans, William E.; Pui, Ching-Hon; Naeve, Clayton W.; Ley, Timothy J.; Mardis, Elaine R.; Wilson, Richard K.; Downing, James R.; Mullighan, Charles G.

    2012-01-01

    Early T-cell precursor acute lymphoblastic leukaemia (ETP ALL) is an aggressive malignancy of unknown genetic basis. We performed whole-genome sequencing of 12 ETP ALL cases and assessed the frequency of the identified somatic mutations in 94 T-cell acute lymphoblastic leukaemia cases. ETP ALL was characterized by activating mutations in genes regulating cytokine receptor and RAS signalling (67% of cases; NRAS, KRAS, FLT3, IL7R, JAK3, JAK1, SH2B3 and BRAF), inactivating lesions disrupting haematopoietic development (58%; GATA3, ETV6, RUNX1, IKZF1 and EP300) and histone-modifying genes (48%; EZH2, EED, SUZ12, SETD2 and EP300). We also identified new targets of recurrent mutation including DNM2, ECT2L and RELN. The mutational spectrum is similar to myeloid tumours, and moreover, the global transcriptional profile of ETP ALL was similar to that of normal and myeloid leukaemia haematopoietic stem cells. These findings suggest that addition of myeloid-directed therapies might improve the poor outcome of ETP ALL. PMID:22237106

  11. Effect of drug precursor in cell uptake and cytotoxicity of redox-responsive camptothecin nanomedicines.

    Science.gov (United States)

    Botella, Pablo; Muniesa, Carlos; Vicente, Víctor; Cabrera-García, Alejandro

    2016-01-01

    Novel redox-responsive nanomedicines have been synthesized by conjugating camptothecin prodrugs ((pyridine-2-yldisulfanil)alkyl carbonate derivatives) to hybrid porous silica nanoparticles through disulfide bond. After disulfide reduction, camptothecin may be released by an intramolecular cyclization mechanism or by carbonate bond hydrolysis. Samples have been characterized by physico-chemical techniques, and stability and drug release in PBS and human serum have been determined. Moreover, cell uptake was studied by fluorescence microscopy and flow cytometry, whilst cytotoxic activity was validated by MTT test. Obtained results indicate that prodrug side chain carbon number (n=1,2,3) determines material hydrophobic properties and, as a consequence, its stability in aqueous medium. When n value increases, the negative surface charge decreases dramatically due to a shielding effect provoked by hydrophobic ligands, which promotes particle aggregation and favors cell internalization. Furthermore, the n value determines the type of products released and, subsequently, the cytotoxic activity. Full disulfide bridge reduction takes place in all cases, but quick delivery of the free drug by intramolecular cyclization is only possible with the shortest linker (n=1), whereas other nanomedicines only present slow discharge of camptothecin by carbonate hydrolysis. Overall, the drug precursor incorporated to the inorganic nanoplatform modulates both cell uptake rate and cytotoxicity according to the different functionalization. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Transplantation of oligodendrocyte precursor cells improves locomotion deficits in rats with spinal cord irradiation injury.

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    Yan Sun

    Full Text Available Demyelination contributes to the functional impairment of irradiation injured spinal cord. One potential therapeutic strategy involves replacing the myelin-forming cells. Here, we asked whether transplantation of Olig2(+-GFP(+-oligodendrocyte precursor cells (OPCs, which are derived from Olig2-GFP-mouse embryonic stem cells (mESCs, could enhance remyelination and functional recovery after spinal cord irradiation injury. We differentiated Olig2-GFP-mESCs into purified Olig2(+-GFP(+-OPCs and transplanted them into the rats' cervical 4-5 dorsal spinal cord level at 4 months after irradiation injury. Eight weeks after transplantation, the Olig2(+-GFP(+-OPCs survived and integrated into the injured spinal cord. Immunofluorescence analysis showed that the grafted Olig2(+-GFP(+-OPCs primarily differentiated into adenomatous polyposis coli (APC(+ oligodendrocytes (54.6±10.5%. The staining with luxol fast blue, hematoxylin & eosin (LFB/H&E and electron microscopy demonstrated that the engrafted Olig2(+-GFP(+-OPCs attenuated the demyelination resulted from the irradiation. More importantly, the recovery of forelimb locomotor function was enhanced in animals receiving grafts of Olig2(+-GFP(+-OPCs. We concluded that OPC transplantation is a feasible therapy to repair the irradiated lesions in the central nervous system (CNS.

  13. All Sequential Dip-Coating Processed Perovskite Layers from an Aqueous Lead Precursor for High Efficiency Perovskite Solar Cells.

    Science.gov (United States)

    Adnan, Muhammad; Lee, Jae Kwan

    2018-02-01

    A novel, sequential method of dip-coating a ZnO covered mesoporous TiO 2 electrode was performed using a non-halide lead precursor in an aqueous system to form a nanoscale perovskite film. The introduction of a ZnO interfacial layer induced significant adsorption in the non-halide lead precursor system. An efficient successive solid-state ion exchange and reaction process improved the morphology, crystallinity, and stability of perovskite solar cells. Improved surface coverage was achieved using successive ionic layer adsorption and reaction processes. When all sequential dipping conditions were controlled, a notable power conversion efficiency of 12.41% under standard conditions (AM 1.5, 100 mW·cm -2 ) was achieved for the perovskite solar cells fabricated from an aqueous non-halide lead precursor solution without spin-casting, which is an environmentally benign and low-cost manufacturing processes.

  14. Post-embryonic nerve-associated precursors to adult pigment cells: genetic requirements and dynamics of morphogenesis and differentiation.

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    Erine H Budi

    2011-05-01

    Full Text Available The pigment cells of vertebrates serve a variety of functions and generate a stunning variety of patterns. These cells are also implicated in human pathologies including melanoma. Whereas the events of pigment cell development have been studied extensively in the embryo, much less is known about morphogenesis and differentiation of these cells during post-embryonic stages. Previous studies of zebrafish revealed genetically distinct populations of embryonic and adult melanophores, the ectotherm homologue of amniote melanocytes. Here, we use molecular markers, vital labeling, time-lapse imaging, mutational analyses, and transgenesis to identify peripheral nerves as a niche for precursors to adult melanophores that subsequently migrate to the skin to form the adult pigment pattern. We further identify genetic requirements for establishing, maintaining, and recruiting precursors to the adult melanophore lineage and demonstrate novel compensatory behaviors during pattern regulation in mutant backgrounds. Finally, we show that distinct populations of latent precursors having differential regenerative capabilities persist into the adult. These findings provide a foundation for future studies of post-embryonic pigment cell precursors in development, evolution, and neoplasia.

  15. Sequence conservation and combinatorial complexity of Drosophila neural precursor cell enhancers

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    Kuzin Alexander

    2008-08-01

    Full Text Available Abstract Background The presence of highly conserved sequences within cis-regulatory regions can serve as a valuable starting point for elucidating the basis of enhancer function. This study focuses on regulation of gene expression during the early events of Drosophila neural development. We describe the use of EvoPrinter and cis-Decoder, a suite of interrelated phylogenetic footprinting and alignment programs, to characterize highly conserved sequences that are shared among co-regulating enhancers. Results Analysis of in vivo characterized enhancers that drive neural precursor gene expression has revealed that they contain clusters of highly conserved sequence blocks (CSBs made up of shorter shared sequence elements which are present in different combinations and orientations within the different co-regulating enhancers; these elements contain either known consensus transcription factor binding sites or consist of novel sequences that have not been functionally characterized. The CSBs of co-regulated enhancers share a large number of sequence elements, suggesting that a diverse repertoire of transcription factors may interact in a highly combinatorial fashion to coordinately regulate gene expression. We have used information gained from our comparative analysis to discover an enhancer that directs expression of the nervy gene in neural precursor cells of the CNS and PNS. Conclusion The combined use EvoPrinter and cis-Decoder has yielded important insights into the combinatorial appearance of fundamental sequence elements required for neural enhancer function. Each of the 30 enhancers examined conformed to a pattern of highly conserved blocks of sequences containing shared constituent elements. These data establish a basis for further analysis and understanding of neural enhancer function.

  16. Gold- and silver nanoparticles affect the growth characteristics of human embryonic neural precursor cells.

    Directory of Open Access Journals (Sweden)

    Erika Söderstjerna

    Full Text Available Rapid development of nanotechnologies and their applications in clinical research have raised concerns about the adverse effects of nanoparticles (NPs on human health and environment. NPs can be directly taken up by organs exposed, but also translocated to secondary organs, such as the central nervous system (CNS after systemic- or subcutaneous administration, or via the olfactory system. The CNS is particularly vulnerable during development and recent reports describe transport of NPs across the placenta and even into brain tissue using in vitro and in vivo experimental systems. Here, we investigated whether well-characterized commercial 20 and 80 nm Au- and AgNPs have an effect on human embryonic neural precursor cell (HNPC growth. After two weeks of NP exposure, uptake of NPs, morphological features and the amount of viable and dead cells, proliferative cells (Ki67 immunostaining and apoptotic cells (TUNEL assay, respectively, were studied. We demonstrate uptake of both 20 and 80 nm Au- and AgNPs respectively, by HNPCs during proliferation. A significant effect on the sphere size- and morphology was found for all cultures exposed to Au- and AgNPs. AgNPs of both sizes caused a significant increase in numbers of proliferating and apoptotic HNPCs. In contrast, only the highest dose of 20 nm AuNPs significantly affected proliferation, whereas no effect was seen on apoptotic cell death. Our data demonstrates that both Au- and AgNPs interfere with the growth profile of HNPCs, indicating the need of further detailed studies on the adverse effects of NPs on the developing CNS.

  17. Abnormal neural precursor cell regulation in the early postnatal Fragile X mouse hippocampus.

    Science.gov (United States)

    Sourial, Mary; Doering, Laurie C

    2017-07-01

    The regulation of neural precursor cells (NPCs) is indispensable for a properly functioning brain. Abnormalities in NPC proliferation, differentiation, survival, or integration have been linked to various neurological diseases including Fragile X syndrome. Yet, no studies have examined NPCs from the early postnatal Fragile X mouse hippocampus despite the importance of this developmental time point, which marks the highest expression level of FMRP, the protein missing in Fragile X, in the rodent hippocampus and is when hippocampal NPCs have migrated to the dentate gyrus (DG) to give rise to lifelong neurogenesis. In this study, we examined NPCs from the early postnatal hippocampus and DG of Fragile X mice (Fmr1-KO). Immunocytochemistry on neurospheres showed increased Nestin expression and decreased Ki67 expression, which collectively indicated aberrant NPC biology. Intriguingly, flow cytometric analysis of the expression of the antigens CD15, CD24, CD133, GLAST, and PSA-NCAM showed a decreased proportion of neural stem cells (GLAST + CD15 + CD133 + ) and an increased proportion of neuroblasts (PSA-NCAM + CD15 + ) in the DG of P7 Fmr1-KO mice. This was mirrored by lower expression levels of Nestin and the mitotic marker phospho-histone H3 in vivo in the P9 hippocampus, as well as a decreased proportion of cells in the G 2 /M phases of the P7 DG. Thus, the absence of FMRP leads to fewer actively cycling NPCs, coinciding with a decrease in neural stem cells and an increase in neuroblasts. Together, these results show the importance of FMRP in the developing hippocampal formation and suggest abnormalities in cell cycle regulation in Fragile X. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

  18. Postembryonic fast muscle growth of teleost fish depends upon a nonuniformly distributed population of mitotically active Pax7+ precursor cells.

    Science.gov (United States)

    Marschallinger, J; Obermayer, A; Sänger, A M; Stoiber, W; Steinbacher, Peter

    2009-09-01

    Muscle development in teleost embryos has been shown to depend on myogenic cell recruitment from the dermomyotome (DM). However, little is known as to the cellular mechanisms that account for myotome growth after the dissociation of the DM. Here we combine immunolabeling for cell-specific markers with quantitative analysis to determine the sources and patterns of activation of myogenic cells in pearlfish larvae. Results demonstrate that appearance of mitotically active myogenic precursors inside the myotome coincides with the dissociation of the DM. Such cells are preferentially aggregated within the posterior lateral fast muscle. We therefore propose a growth model in which a pool of proliferative DM-derived precursors transferred to the posterior lateral fast muscle functions as an important source of myogenic cell spread to carry forward stratified fast muscle hyperplasia. This indicates that postembryonic teleost muscle growth includes a cellular mechanism that has no direct equivalent in the amniotes.

  19. Functional plasticity of the N-methyl-d-aspartate receptor in differentiating human erythroid precursor cells.

    Science.gov (United States)

    Hänggi, Pascal; Telezhkin, Vsevolod; Kemp, Paul J; Schmugge, Markus; Gassmann, Max; Goede, Jeroen S; Speer, Oliver; Bogdanova, Anna

    2015-06-15

    Calcium signaling is essential to support erythroid proliferation and differentiation. Precise control of the intracellular Ca(2+) levels in erythroid precursor cells (EPCs) is afforded by coordinated expression and function of several cation channels, including the recently identified N-methyl-d-aspartate receptor (NMDAR). Here, we characterized the changes in Ca(2+) uptake and electric currents mediated by the NMDARs occurring during EPC differentiation using flow cytometry and patch clamp. During erythropoietic maturation, subunit composition and properties of the receptor changed; in proerythroblasts and basophilic erythroblasts, fast deactivating currents with high amplitudes were mediated by the GluN2A subunit-dominated receptors, while at the polychromatic and orthochromatic erythroblast stages, the GluN2C subunit was getting more abundant, overriding the expression of GluN2A. At these stages, the currents mediated by the NMDARs carried the features characteristic of the GluN2C-containing receptors, such as prolonged decay time and lower conductance. Kinetics of this switch in NMDAR properties and abundance varied markedly from donor to donor. Despite this variability, NMDARs were essential for survival of EPCs in any subject tested. Our findings indicate that NMDARs have a dual role during erythropoiesis, supporting survival of polychromatic erythroblasts and contributing to the Ca(2+) homeostasis from the orthochromatic erythroblast stage to circulating red blood cells. Copyright © 2015 the American Physiological Society.

  20. A new role for interferon gamma in neural stem/precursor cell dysregulation

    Directory of Open Access Journals (Sweden)

    Hartung Hans-Peter

    2011-03-01

    Full Text Available Abstract Background The identification of factors that compromise neurogenesis is aimed at improving stem cell-based approaches in the field of regenerative medicine. Interferon gamma (IFNγ is a main pro-inflammatory cytokine and up-regulated during several neurological diseases. IFNγ is generally thought to beneficially enhance neurogenesis from fetal or adult neural stem/precursor cells (NSPCs. Results We now provide direct evidence to the contrary that IFNγ induces a dysfunctional stage in a substantial portion of NSPC-derived progeny in vitro characterized by simultaneous expression of glial fibrillary acid protein (GFAP and neuronal markers, an abnormal gene expression and a functional phenotype neither typical for neurons nor for mature astrocytes. Dysfunctional development of NSPCs under the influence of IFNγ was finally demonstrated by applying the microelectrode array technology. IFNγ exposure of NSPCs during an initial 7-day proliferation period prevented the subsequent adequate differentiation and formation of functional neuronal networks. Conclusions Our results show that immunocytochemical analyses of NSPC-derived progeny are not necessarily indicating the correct cellular phenotype specifically under inflammatory conditions and that simultaneous expression of neuronal and glial markers rather point to cellular dysregulation. We hypothesize that inhibiting the impact of IFNγ on NSPCs during neurological diseases might contribute to effective neurogenesis and regeneration.

  1. CD73 protein as a source of extracellular precursors for sustained NAD+ biosynthesis in FK866-treated tumor cells.

    Science.gov (United States)

    Grozio, Alessia; Sociali, Giovanna; Sturla, Laura; Caffa, Irene; Soncini, Debora; Salis, Annalisa; Raffaelli, Nadia; De Flora, Antonio; Nencioni, Alessio; Bruzzone, Santina

    2013-09-06

    NAD(+) is mainly synthesized in human cells via the "salvage" pathways starting from nicotinamide, nicotinic acid, or nicotinamide riboside (NR). The inhibition with FK866 of the enzyme nicotinamide phosphoribosyltransferase (NAMPT), catalyzing the first reaction in the "salvage" pathway from nicotinamide, showed potent antitumor activity in several preclinical models of solid and hematologic cancers. In the clinical studies performed with FK866, however, no tumor remission was observed. Here we demonstrate that low micromolar concentrations of extracellular NAD(+) or NAD(+) precursors, nicotinamide mononucleotide (NMN) and NR, can reverse the FK866-induced cell death, this representing a plausible explanation for the failure of NAMPT inhibition as an anti-cancer therapy. NMN is a substrate of both ectoenzymes CD38 and CD73, with generation of NAM and NR, respectively. In this study, we investigated the roles of CD38 and CD73 in providing ectocellular NAD(+) precursors for NAD(+) biosynthesis and in modulating cell susceptibility to FK866. By specifically silencing or overexpressing CD38 and CD73, we demonstrated that endogenous CD73 enables, whereas CD38 impairs, the conversion of extracellular NMN to NR as a precursor for intracellular NAD(+) biosynthesis in human cells. Moreover, cell viability in FK866-treated cells supplemented with extracellular NMN was strongly reduced in tumor cells, upon pharmacological inhibition or specific down-regulation of CD73. Thus, our study suggests that genetic or pharmacologic interventions interfering with CD73 activity may prove useful to increase cancer cell sensitivity to NAMPT inhibitors.

  2. In vitro cultured progenitors and precursors of cardiac cell lineages from human normal and post-ischemic hearts

    Directory of Open Access Journals (Sweden)

    F Di Meglio

    2009-08-01

    Full Text Available The demonstration of the presence of dividing primitive cells in damaged hearts has sparked increased interest about myocardium regenerative processes. We examined the rate and the differentiation of in vitro cultured resident cardiac primitive cells obtained from pathological and normal human hearts in order to evaluate the activation of progenitors and precursors of cardiac cell lineages in post-ischemic human hearts. The precursors and progenitors of cardiomyocyte, smooth muscle and endothelial lineage were identified by immunocytochemistry and the expression of characteristic markers was studied by western blot and RT-PCR. The amount of proteins characteristic for cardiac cells (a-SA and MHC, VEGFR-2 and FVIII, SMA for the precursors of cardiomyocytes, endothelial and smooth muscle cells, respectively inclines toward an increase in both a-SA and MHC. The increased levels of FVIII and VEGFR2 are statistically significant, suggesting an important re-activation of neoangiogenesis. At the same time, the augmented expression of mRNA for Nkx 2.5, the trascriptional factor for cardiomyocyte differentiation, confirms the persistence of differentiative processes in terminally injured hearts. Our study would appear to confirm the activation of human heart regeneration potential in pathological conditions and the ability of its primitive cells to maintain their proliferative capability in vitro. The cardiac cell isolation method we used could be useful in the future for studying modifications to the microenvironment that positively influence cardiac primitive cell differentiation or inhibit, or retard, the pathological remodeling and functional degradation of the heart.

  3. Consumption of the epidermis: a suggested precursor of ulceration associated with increased proliferation of melanoma cells.

    Science.gov (United States)

    Bønnelykke-Behrndtz, Louise M; Schmidt, Henrik; Damsgaard, Tine E; Christensen, Ib Jarle; Bastholt, Lars; Møller, Holger J; Nørgaard, Peter; Steiniche, Torben

    2015-11-01

    It has recently been demonstrated that the extent of ulceration and the presence of epidermal involvement that theoretically precede ulceration (consumption of epidermis, COE) or seen subsequent to inflammation (reactive epidermal hyperplasia or re-epithelialization) allowed better prognostic stratification of ulcerated melanoma. Understanding why these histopathologic markers have prognostic potential is important, not least because accurate consensual assessment of ulceration lies at the root of proper staging and clinical management. The authors therefore performed immunohistochemical analyses of tumor cell proliferation (Melan-A/Ki67) and infiltration of inflammatory cells (CD66b neutrophils and CD163 macrophages) to better understand the biology of the epidermal changes described. Tumors with a COE configuration showed 37% (95% CI: 4-54, P = 0.0046) increased tumor cell proliferation compared with tumors of normal epidermal configuration. COE is therefore suggested a precursor of ulceration associated with increased proliferation of melanoma cells. There was no observed correlation between COE and an increased inflammatory response (CD163 macrophages or CD66b neutrophils), which supports that the proliferation drive is noninflammatory. In contrast, the presence of re-epithelialization and/or reactive epidermal hyperplasia demonstrated an 18% (95% CI: 6-53, P = 0.0021) increased density of neutrophils compared with tumor with no evidence of these possibly prolonged late-stage or resolved ulcerations. These results further support the relevance of including these epidermal changes into the definition of ulceration and to define ulceration of a primary melanoma as loss of epidermis with evidence of a host response (infiltration of neutrophils or fibrin deposition) and thinning, effacement, or reactive hyperplasia of the surrounding epidermis.

  4. Noninvasive PET Imaging and Tracking of Engineered Human Muscle Precursor Cells for Skeletal Muscle Tissue Engineering.

    Science.gov (United States)

    Haralampieva, Deana; Betzel, Thomas; Dinulovic, Ivana; Salemi, Souzan; Stoelting, Meline; Krämer, Stefanie D; Schibli, Roger; Sulser, Tullio; Handschin, Christoph; Eberli, Daniel; Ametamey, Simon M

    2016-09-01

    Transplantation of human muscle precursor cells (hMPCs) is envisioned for the treatment of various muscle diseases. However, a feasible noninvasive tool to monitor cell survival, migration, and integration into the host tissue is still missing. In this study, we designed an adenoviral delivery system to genetically modify hMPCs to express a signaling-deficient form of human dopamine D2 receptor (hD2R). The gene expression levels of the receptor were evaluated by reverse transcriptase polymerase chain reaction, and infection efficiency was evaluated by fluorescent microscopy. The viability, proliferation, and differentiation capacity of the transduced cells, as well as their myogenic phenotype, were determined by flow cytometry analysis and fluorescent microscopy. (18)F-fallypride and (18)F-fluoromisonidazole, two well-established PET radioligands, were assessed for their potential to image engineered hMPCs in a mouse model and their uptakes were evaluated at different time points after cell inoculation in vivo. Biodistribution studies, autoradiography, and PET experiments were performed to determine the extent of signal specificity. To address feasibility for tracking hMPCs in an in vivo model, the safety of the adenoviral gene delivery was evaluated. Finally, the harvested tissues were histologically examined to determine whether survival of the transplanted cells was sustained at different time points. Adenoviral gene delivery was shown to be safe, with no detrimental effects on the primary human cells. The viability, proliferation, and differentiation capacity of the transduced cells were confirmed, and flow cytometry analysis and fluorescent microscopy showed that their myogenic phenotype was sustained. (18)F-fallypride and (18)F-fluoromisonidazole were successfully synthesized. Specific binding of (18)F-fallypride to hD2R hMPCs was demonstrated in vitro and in vivo. Furthermore, the (18)F-fluoromisonidazole signal was high at the early stages. Finally

  5. Enhanced proliferation and dopaminergic differentiation of ventral mesencephalic precursor cells by synergistic effect of FGF2 and reduced oxygen tension

    DEFF Research Database (Denmark)

    Jensen, Pia; Gramsbergen, Jan-Bert; Zimmer, Jens

    2011-01-01

    Effective numerical expansion of dopaminergic precursors might overcome the limited availability of transplantable cells in replacement strategies for Parkinson's disease. Here we investigated the effect of fibroblast growth factor-2 (FGF2) and FGF8 on expansion and dopaminergic differentiation o...

  6. Combined transplantation of neural precursor cells and olfactory ensheathing cells for the treatment of X-linked adrenoleukodystrophy in children

    Directory of Open Access Journals (Sweden)

    Yang H

    2017-04-01

    Full Text Available Hui Yang,1,* Yu Zhang,1,* Zhaoyan Wang,1 Wei Lu,1 Fang Liu,1 Xin Yu,2 Xiaoyan Zheng,1 Yinxiang Yang,1 Zuo Luan,1 Suqing Qu1 1Department of Pediatrics, 2Department of Neurological Surgery, Navy General Hospital, Beijing, People’s Republic of China *These authors contributed equally to this work. Abstract: Hematopoietic stem cell transplantation is only suitable for early-stage adrenoleukodystrophy (ALD. In this study, we observed the therapeutic efficacy of combined transplantation of neural precursor cells (NPCs and olfactory ensheathing cells (OECs on late-stage X-linked ALD in nine children who were admitted in our hospital between June 2009 and January 2014. Related patient information included onset time 3 months to 1 year, magnetic resonance imaging (MRI score 11.02±0.90, and neurologic function score 2–3. All patients received combined transplantation of NPCs and OECs by injection around the lateral angle of the frontotemporal–occipital lesion under MRI guidance. It was found that the visual function, sleep, and communication obstacles were improved significantly without evidence of disease progression in six (66.7% of the nine patients within 1 month after transplantation. In two of the six patients, the lesions became significantly smaller than before, although their MRI scores remained unchanged significantly. In addition, cell therapy did not induce any irreversible adverse event during the study period, indicating that combined transplantation of NPCs and OECs was safe and reliable, and could improve the clinical manifestations of ALD in children within a short time. Although this cell therapy was not able to halt the progression of the disease 1–3 months after transplantation, it could still be used as an early treatment and provide patients with more opportunities for hematopoietic stem cell transplantation, which is the only effective long-term treatment for X-linked ALD at present. The preliminary results from this study

  7. Ago2 immunoprecipitation identifies predicted microRNAs in human embryonic stem cells and neural precursors.

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    Loyal A Goff

    2009-09-01

    Full Text Available MicroRNAs are required for maintenance of pluripotency as well as differentiation, but since more microRNAs have been computationally predicted in genome than have been found, there are likely to be undiscovered microRNAs expressed early in stem cell differentiation.SOLiD ultra-deep sequencing identified >10(7 unique small RNAs from human embryonic stem cells (hESC and neural-restricted precursors that were fit to a model of microRNA biogenesis to computationally predict 818 new microRNA genes. These predicted genomic loci are associated with chromatin patterns of modified histones that are predictive of regulated gene expression. 146 of the predicted microRNAs were enriched in Ago2-containing complexes along with 609 known microRNAs, demonstrating association with a functional RISC complex. This Ago2 IP-selected subset was consistently expressed in four independent hESC lines and exhibited complex patterns of regulation over development similar to previously-known microRNAs, including pluripotency-specific expression in both hESC and iPS cells. More than 30% of the Ago2 IP-enriched predicted microRNAs are new members of existing families since they share seed sequences with known microRNAs.Extending the classic definition of microRNAs, this large number of new microRNA genes, the majority of which are less conserved than their canonical counterparts, likely represent evolutionarily recent regulators of early differentiation. The enrichment in Ago2 containing complexes, the presence of chromatin marks indicative of regulated gene expression, and differential expression over development all support the identification of 146 new microRNAs active during early hESC differentiation.

  8. Intrinsic Differences in Adipocyte Precursor Cells From Different White Fat Depots

    Science.gov (United States)

    Macotela, Yazmín; Emanuelli, Brice; Mori, Marcelo A.; Gesta, Stephane; Schulz, Tim J.; Tseng, Yu-Hua; Kahn, C. Ronald

    2012-01-01

    Obesity and body fat distribution are important risk factors for the development of type 2 diabetes and metabolic syndrome. Evidence has accumulated that this risk is related to intrinsic differences in behavior of adipocytes in different fat depots. In the current study, we demonstrate that adipocyte precursor cells (APCs) isolated from visceral and subcutaneous white adipose depots of mice have distinct patterns of gene expression, differentiation potential, and response to environmental and genetic influences. APCs derived from subcutaneous fat differentiate well in the presence of classical induction cocktail, whereas those from visceral fat differentiate poorly but can be induced to differentiate by addition of bone morphogenetic protein (BMP)-2 or BMP-4. This difference correlates with major differences in gene expression signature between subcutaneous and visceral APCs. The number of APCs is higher in obesity-prone C57BL/6 mice than obesity-resistant 129 mice, and the number in both depots is increased by up to 270% by exposure of mice to high-fat diet. Thus, APCs from visceral and subcutaneous depots are dynamic populations, which have intrinsic differences in gene expression, differentiation properties, and responses to environmental/genetic factors. Regulation of these populations may provide a new target for the treatment and prevention of obesity and its metabolic complications. PMID:22596050

  9. Isolation of Mature (Peritoneum-Derived Mast Cells and Immature (Bone Marrow-Derived Mast Cell Precursors from Mice.

    Directory of Open Access Journals (Sweden)

    Steffen K Meurer

    Full Text Available Mast cells (MCs are a versatile cell type playing key roles in tissue morphogenesis and host defence against bacteria and parasites. Furthermore, they can enhance immunological danger signals and are implicated in inflammatory disorders like fibrosis. This granulated cell type originates from the myeloid lineage and has similarities to basophilic granulocytes, both containing large quantities of histamine and heparin. Immature murine mast cells mature in their destination tissue and adopt either the connective tissue (CTMC or mucosal (MMC type. Some effector functions are executed by activation/degranulation of MCs which lead to secretion of a typical set of MC proteases (MCPT and of the preformed or newly synthesized mediators from its granules into the local microenvironment. Due to the potential accumulation of mutations in key signalling pathway components of corresponding MC cell-lines, primary cultured MCs are an attractive mean to study general features of MC biology and aspects of MC functions relevant to human disease. Here, we describe a simple protocol for the simultaneous isolation of mature CTMC-like murine MCs from the peritoneum (PMCs and immature MC precursors from the bone marrow (BM. The latter are differentiated in vitro to yield BM-derived MCs (BMMC. These cells display the typical morphological and phenotypic features of MCs, express the typical MC surface markers, and can be propagated and kept in culture for several weeks. The provided protocol allows simple amplification of large quantities of homogenous, non-transformed MCs from the peritoneum and bone marrow-derived mast cells for cell- and tissue-based biomedical research.

  10. Myogenic Precursors from iPS Cells for Skeletal Muscle Cell Replacement Therapy

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    Isart Roca

    2015-01-01

    Full Text Available The use of adult myogenic stem cells as a cell therapy for skeletal muscle regeneration has been attempted for decades, with only moderate success. Myogenic progenitors (MP made from induced pluripotent stem cells (iPSCs are promising candidates for stem cell therapy to regenerate skeletal muscle since they allow allogenic transplantation, can be produced in large quantities, and, as compared to adult myoblasts, present more embryonic-like features and more proliferative capacity in vitro, which indicates a potential for more self-renewal and regenerative capacity in vivo. Different approaches have been described to make myogenic progenitors either by gene overexpression or by directed differentiation through culture conditions, and several myopathies have already been modeled using iPSC-MP. However, even though results in animal models have shown improvement from previous work with isolated adult myoblasts, major challenges regarding host response have to be addressed and clinically relevant transplantation protocols are lacking. Despite these challenges we are closer than we think to bringing iPSC-MP towards clinical use for treating human muscle disease and sporting injuries.

  11. Opioid precursor protein isoform is targeted to the cell nuclei in the human brain

    DEFF Research Database (Denmark)

    Kononenko, Olga; Bazov, Igor; Watanabe, Hiroyuki

    2017-01-01

    Neuropeptide precursors are traditionally viewed as proteins giving rise to small neuropeptide molecules. Prodynorphin (PDYN) is the precursor protein to dynorphins, endogenous ligands for the κ-opioid receptor. We here describe two novel splicing variants of human PDYN mRNA. Expression of one...... isolated from human striatum using fluorescence-activated nuclei sorting, and by immunofluorescence staining and confocal microscopy in the human caudate nucleus. These results along with the presence of putative NLS in other neuropeptide precursors raise questions of the nuclear localization is a general...

  12. Skin-Derived Precursor Cells Promote Angiogenesis and Stimulate Proliferation of Endogenous Neural Stem Cells after Cerebral Infarction

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    Duo Mao

    2015-01-01

    Full Text Available Stroke is one of the most common diseases that caused high mortality and has become burden to the health care systems. Stem cell transplantation has shown therapeutic effect in ameliorating ischemic damage after cerebral artery occlusion mainly due to their neurogenesis, immune regulation, or effects on the plasticity, proliferation, and survival of host cells. Recent studies demonstrated that skin-derived precursor cells (SKPs could promote central nervous system regeneration in spinal cord injury model or the neonatal peripheral neuron. Here, we investigated the therapeutic potential of SKPs in a rat model of cerebral ischemia. SKPs were isolated, expanded, and transplanted into rat cortex and striatum after transient middle cerebral artery occlusion. Our results revealed that SKPs transplantation could improve the behavioral measures of neurological deficit. Moreover, immunohistology confirmed that SKPs could secrete basic FGF and VEGF in the ischemic region and further markedly increase the proliferation of endogenous nestin+ and βIII-tubulin+ neural stem cells. Furthermore, increased angiogenesis induced by SKPs was observed by vWF and α-SMA staining. These data suggest that SKPs induced endogenous neurogenesis and angiogenesis and protected neuron from hypoxic-ischemic environment. In conclusion, SKPs transplantation may be a promising approach in treatment of stroke.

  13. Whole-genome DNA methylation characteristics in pediatric precursor B cell acute lymphoblastic leukemia (BCP ALL.

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    Radosław Chaber

    Full Text Available In addition to genetic alterations, epigenetic abnormalities have been shown to underlie the pathogenesis of acute lymphoblastic leukemia (ALL-the most common pediatric cancer. The purpose of this study was to characterize the whole genome DNA methylation profile in children with precursor B-cell ALL (BCP ALL and to compare this profile with methylation observed in normal bone marrow samples. Additional efforts were made to correlate the observed methylation patterns with selected clinical features. We assessed DNA methylation from bone marrow samples obtained from 38 children with BCP ALL at the time of diagnosis along with 4 samples of normal bone marrow cells as controls using Infinium MethylationEPIC BeadChip Array. Patients were diagnosed and stratified into prognosis groups according to the BFM ALL IC 2009 protocol. The analysis of differentially methylated sites across the genome as well as promoter methylation profiles allowed clear separation of the leukemic and control samples into two clusters. 86.6% of the promoter-associated differentially methylated sites were hypermethylated in BCP ALL. Seven sites were found to correlate with the BFM ALL IC 2009 high risk group. Amongst these, one was located within the gene body of the MBP gene and another was within the promoter region- PSMF1 gene. Differentially methylated sites that were significantly related with subsets of patients with ETV6-RUNX1 fusion and hyperdiploidy. The analyzed translocations and change of genes' sequence context does not affect methylation and methylation seems not to be a mechanism for the regulation of expression of the resulting fusion genes.

  14. Anosmin-1 over-expression regulates oligodendrocyte precursor cell proliferation, migration and myelin sheath thickness.

    Science.gov (United States)

    Murcia-Belmonte, Verónica; Esteban, Pedro F; Martínez-Hernández, José; Gruart, Agnès; Luján, Rafael; Delgado-García, José María; de Castro, Fernando

    2016-04-01

    During development of the central nervous system, anosmin-1 (A1) works as a chemotropic cue contributing to axonal outgrowth and collateralization, as well as modulating the migration of different cell types, fibroblast growth factor receptor 1 (FGFR1) being the main receptor involved in all these events. To further understand the role of A1 during development, we have analysed the over-expression of human A1 in a transgenic mouse line. Compared with control mice during development and in early adulthood, A1 over-expressing transgenic mice showed an enhanced oligodendrocyte precursor cell (OPC) proliferation and a higher number of OPCs in the subventricular zone and in the corpus callosum (CC). The migratory capacity of OPCs from the transgenic mice is increased in vitro due to a higher basal activation of ERK1/2 mediated through FGFR1 and they also produced more myelin basic protein (MBP). In vivo, the over-expression of A1 resulted in an elevated number of mature oligodendrocytes with higher levels of MBP mRNA and protein, as well as increased levels of activation of the ERK1/2 proteins, while electron microscopy revealed thicker myelin sheaths around the axons of the CC in adulthood. Also in the mature CC, the nodes of Ranvier were significantly longer and the conduction velocity of the nerve impulse in vivo was significantly increased in the CC of A1 over-expressing transgenic mice. Altogether, these data confirmed the involvement of A1 in oligodendrogliogenesis and its relevance for myelination.

  15. Immune regulatory neural stem/precursor cells protect from central nervous system autoimmunity by restraining dendritic cell function.

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    Stefano Pluchino

    Full Text Available BACKGROUND: The systemic injection of neural stem/precursor cells (NPCs provides remarkable amelioration of the clinico-pathological features of experimental autoimmune encephalomyelitis (EAE. This is dependent on the capacity of transplanted NPCs to engage concurrent mechanisms of action within specific microenvironments in vivo. Among a wide range of therapeutic actions alternative to cell replacement, neuroprotective and immune modulatory capacities of transplanted NPCs have been described. However, lacking is a detailed understanding of the mechanisms by which NPCs exert their therapeutic plasticity. This study was designed to identify the first candidate that exemplifies and sustains the immune modulatory capacity of transplanted NPCs. METHODOLOGY/PRINCIPAL FINDINGS: To achieve the exclusive targeting of the peripheral immune system, SJL mice with PLP-induced EAE were injected subcutaneously with NPCs and the treatment commenced prior to disease onset. NPC-injected EAE mice showed significant clinical improvement, as compared to controls. Exogenous NPCs lacking the expression of major neural antigens were reliably (and for long-term found at the level of draining lymph nodes, while establishing sophisticated anatomical interactions with lymph node cells. Importantly, injected NPCs were never found in organs other than lymph nodes, including the brain and the spinal cord. Draining lymph nodes from transplanted mice showed focal up-regulation of major developmental stem cell regulators, such as BMP-4, Noggin and Sonic hedgehog. In lymph nodes, injected NPCs hampered the activation of myeloid dendritic cells (DCs and steadily restrained the expansion of antigen-specific encephalitogenic T cells. Both ex vivo and in vitro experiments identified a novel highly NPC-specific-BMP-4-dependent-mechanism hindering the DC maturation. CONCLUSION/SIGNIFICANCE: The study described herein, identifies the first member of the TGF beta/BMP family of stem cell

  16. EPO Receptor Gain-of-Function Causes Hereditary Polycythemia, Alters CD34+ Cell Differentiation and Increases Circulating Endothelial Precursors

    Science.gov (United States)

    Perrotta, Silverio; Cucciolla, Valeria; Ferraro, Marcella; Ronzoni, Luisa; Tramontano, Annunziata; Rossi, Francesca; Scudieri, Anna Chiara; Borriello, Adriana; Roberti, Domenico; Nobili, Bruno; Cappellini, Maria Domenica; Oliva, Adriana; Amendola, Giovanni; Migliaccio, Anna Rita; Mancuso, Patrizia; Martin-Padura, Ines; Bertolini, Francesco; Yoon, Donghoon; Prchal, Josef T.; Della Ragione, Fulvio

    2010-01-01

    Background Gain-of-function of erythropoietin receptor (EPOR) mutations represent the major cause of primary hereditary polycythemia. EPOR is also found in non-erythroid tissues, although its physiological role is still undefined. Methodology/Principal Findings We describe a family with polycythemia due to a heterozygous mutation of the EPOR gene that causes a G→T change at nucleotide 1251 of exon 8. The novel EPOR G1251T mutation results in the replacement of a glutamate residue by a stop codon at amino acid 393. Differently from polycythemia vera, EPOR G1251T CD34+ cells proliferate and differentiate towards the erythroid phenotype in the presence of minimal amounts of EPO. Moreover, the affected individuals show a 20-fold increase of circulating endothelial precursors. The analysis of erythroid precursor membranes demonstrates a heretofore undescribed accumulation of the truncated EPOR, probably due to the absence of residues involved in the EPO-dependent receptor internalization and degradation. Mutated receptor expression in EPOR-negative cells results in EPOR and Stat5 phosphorylation. Moreover, patient erythroid precursors present an increased activation of EPOR and its effectors, including Stat5 and Erk1/2 pathway. Conclusions/Significance Our data provide an unanticipated mechanism for autosomal dominant inherited polycythemia due to a heterozygous EPOR mutation and suggest a regulatory role of EPO/EPOR pathway in human circulating endothelial precursors homeostasis. PMID:20700488

  17. EPO receptor gain-of-function causes hereditary polycythemia, alters CD34 cell differentiation and increases circulating endothelial precursors.

    Directory of Open Access Journals (Sweden)

    Silverio Perrotta

    2010-08-01

    Full Text Available Gain-of-function of erythropoietin receptor (EPOR mutations represent the major cause of primary hereditary polycythemia. EPOR is also found in non-erythroid tissues, although its physiological role is still undefined.We describe a family with polycythemia due to a heterozygous mutation of the EPOR gene that causes a G-->T change at nucleotide 1251 of exon 8. The novel EPOR G1251T mutation results in the replacement of a glutamate residue by a stop codon at amino acid 393. Differently from polycythemia vera, EPOR G1251T CD34(+ cells proliferate and differentiate towards the erythroid phenotype in the presence of minimal amounts of EPO. Moreover, the affected individuals show a 20-fold increase of circulating endothelial precursors. The analysis of erythroid precursor membranes demonstrates a heretofore undescribed accumulation of the truncated EPOR, probably due to the absence of residues involved in the EPO-dependent receptor internalization and degradation. Mutated receptor expression in EPOR-negative cells results in EPOR and Stat5 phosphorylation. Moreover, patient erythroid precursors present an increased activation of EPOR and its effectors, including Stat5 and Erk1/2 pathway.Our data provide an unanticipated mechanism for autosomal dominant inherited polycythemia due to a heterozygous EPOR mutation and suggest a regulatory role of EPO/EPOR pathway in human circulating endothelial precursors homeostasis.

  18. The effect of magnetic nanoparticles on neuronal differentiation of induced pluripotent stem cell-derived neural precursors

    Science.gov (United States)

    Jiráková, Klára; Šeneklová, Monika; Jirák, Daniel; Turnovcová, Karolína; Vosmanská, Magda; Babič, Michal; Horák, Daniel; Veverka, Pavel; Jendelová, Pavla

    2016-01-01

    Introduction Magnetic resonance (MR) imaging is suitable for noninvasive long-term tracking. We labeled human induced pluripotent stem cell-derived neural precursors (iPSC-NPs) with two types of iron-based nanoparticles, silica-coated cobalt zinc ferrite nanoparticles (CZF) and poly-l-lysine-coated iron oxide superparamagnetic nanoparticles (PLL-coated γ-Fe2O3) and studied their effect on proliferation and neuronal differentiation. Materials and methods We investigated the effect of these two contrast agents on neural precursor cell proliferation and differentiation capability. We further defined the intracellular localization and labeling efficiency and analyzed labeled cells by MR. Results Cell proliferation was not affected by PLL-coated γ-Fe2O3 but was slowed down in cells labeled with CZF. Labeling efficiency, iron content and relaxation rates measured by MR were lower in cells labeled with CZF when compared to PLL-coated γ-Fe2O3. Cytoplasmic localization of both types of nanoparticles was confirmed by transmission electron microscopy. Flow cytometry and immunocytochemical analysis of specific markers expressed during neuronal differentiation did not show any significant differences between unlabeled cells or cells labeled with both magnetic nanoparticles. Conclusion Our results show that cells labeled with PLL-coated γ-Fe2O3 are suitable for MR detection, did not affect the differentiation potential of iPSC-NPs and are suitable for in vivo cell therapies in experimental models of central nervous system disorders. PMID:27920532

  19. Precursor T-cell acute lymphoblastic leukemia presenting with bone marrow necrosis: a case report

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    Khoshnaw Najmaddin SH

    2012-10-01

    Full Text Available Abstract Introduction Bone marrow necrosis is a clinicopathological condition diagnosed most often at postmortem examination, but it is also seen during the course of malignancy and is not always associated with a poor prognosis. The morphological features of bone marrow necrosis are disruption of the normal marrow architecture and necrosis of myeloid tissue and medullary stroma. Non-malignant conditions associated with bone marrow necrosis are sickle cell anemia, infections, drugs (sulfasalazine, interferon α, all-trans retinoic acid, granulocyte colony-stimulating factor and fludarabine, disseminated intravascular coagulation, antiphospholipid antibody syndrome and acute graft versus host diseases. The malignant causes are leukemia, lymphoma and metastatic carcinomas. Herein we report the case of a patient with precursor T-cell acute lymphoblastic leukemia and bone marrow necrosis at initial presentation. Case presentation A 10-year-old Kurdish boy was presented with generalized bone pain and fever of 1 month’s duration which was associated with sweating, easy fatigability, nose bleeding, breathlessness and severe weight loss. On examination, we observed pallor, tachypnea, tachycardia, low blood pressure, fever, petechial hemorrhage, ecchymoses, tortuous dilated veins over the chest and upper part of abdomen, multiple small cervical lymph node enlargements, mildly enlarged spleen, palpable liver and gross abdominal distention. Blood analysis revealed pancytopenia and elevated lactate dehydrogenase and erythrocyte sedimentation rate. Imaging results showed mediastinal widening on a planar chest X-ray and diffuse focal infiltration of the axial bone marrow on magnetic resonance imaging of the lumbosacral vertebrae. Bone marrow aspiration and biopsy examination showed extensive bone marrow necrosis. Immunophenotyping analysis of the bone marrow biopsy confirmed T-cell acute lymphoblastic leukemia, as CD3 and terminal deoxynucleotidyl

  20. Advanced Precursor Reaction Processing for Cu(InGa)(SeS)2 Solar Cells

    Energy Technology Data Exchange (ETDEWEB)

    Shafarman, William N. [Univ. of Delaware, Newark, DE (United States)

    2015-10-12

    This project “Advanced Precursor Reaction Processing for Cu(InGa)(SeS)2 Solar Cells”, completed by the Institute of Energy Conversion (IEC) at the University of Delaware in collaboration with the Department of Chemical Engineering at the University of Florida, developed the fundamental understanding and technology to increase module efficiency and improve the manufacturability of Cu(InGa)(SeS)2 films using the precursor reaction approach currently being developed by a number of companies. Key results included: (1) development of a three-step H2Se/Ar/H2S reaction process to control Ga distribution through the film and minimizes back contact MoSe2 formation; (2) Ag-alloying to improve precursor homogeneity by avoiding In phase agglomeration, faster reaction and improved adhesion to allow wider reaction process window; (3) addition of Sb, Bi, and Te interlayers at the Mo/precursor junction to produce more uniform precursor morphology and improve adhesion with reduced void formation in reacted films; (4) a precursor structure containing Se and a reaction process to reduce processing time to 5 minutes and eliminate H2Se usage, thereby increasing throughput and reducing costs. All these results were supported by detailed characterization of the film growth, reaction pathways, thermodynamic assessment and device behavior.

  1. Planar Cell Polarity Breaks the Symmetry of PAR Protein Distribution prior to Mitosis in Drosophila Sensory Organ Precursor Cells.

    Science.gov (United States)

    Besson, Charlotte; Bernard, Fred; Corson, Francis; Rouault, Hervé; Reynaud, Elodie; Keder, Alyona; Mazouni, Khalil; Schweisguth, François

    2015-04-20

    During development, cell-fate diversity can result from the unequal segregation of fate determinants at mitosis. Polarization of the mother cell is essential for asymmetric cell division (ACD). It often involves the formation of a cortical domain containing the PAR complex proteins Par3, Par6, and atypical protein kinase C (aPKC). In the fly notum, sensory organ precursor cells (SOPs) divide asymmetrically within the plane of the epithelium and along the body axis to generate two distinct cells. Fate asymmetry depends on the asymmetric localization of the PAR complex. In the absence of planar cell polarity (PCP), SOPs divide with a random planar orientation but still asymmetrically, showing that PCP is dispensable for PAR asymmetry at mitosis. To study when and how the PAR complex localizes asymmetrically, we have used a quantitative imaging approach to measure the planar polarization of the proteins Bazooka (Baz, fly Par3), Par6, and aPKC in living pupae. By using imaging of functional GFP-tagged proteins with image processing and computational modeling, we find that Baz, Par6, and aPKC become planar polarized prior to mitosis in a manner independent of the AuroraA kinase and that PCP is required for the planar polarization of Baz, Par6, and aPKC during interphase. This indicates that a "mitosis rescue" mechanism establishes asymmetry at mitosis in PCP mutants. This study therefore identifies PCP as the initial symmetry-breaking signal for the planar polarization of PAR proteins in asymmetrically dividing SOPs. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Plasma as a scaffold for regeneration of neural precursor cells after transplantation into rats with spinal cord injury.

    Science.gov (United States)

    Takenaga, Mitsuko; Ohta, Yuki; Tokura, Yukie; Hamaguchi, Akemi; Suzuki, Noboru; Nakamura, Masaya; Okano, Hideyuki; Igarashi, Rie

    2007-01-01

    The present study investigated whether plasma could be useful as a scaffold for cell transplantation in rats with spinal cord injury (SCI). Transplantation of cells with plasma promoted the recovery of SCI-induced motor dysfunction. Immunohistochemical analysis revealed that the grafted cells had differentiated into the neural lineage. When dissociated neural precursor cells were cultured with plasma, extensive neurite outgrowth was observed along with increased expression of p35 and NF68. Neural markers were also expressed by the cultured cells. Culture with plasma reduced thymidine incorporation, but promoted cell growth and increased the RNA contents. These findings suggest that the cells underwent differentiation into neurons in the presence of plasma. In conclusion, plasma could be a promising scaffold for cell transplantation therapy.

  3. Polysialic acid modification of the synaptic cell adhesion molecule SynCAM 1 in human embryonic stem cell-derived oligodendrocyte precursor cells.

    Science.gov (United States)

    Werneburg, Sebastian; Buettner, Falk F R; Mühlenhoff, Martina; Hildebrandt, Herbert

    2015-05-01

    Oligodendrocyte precursor cells (OPCs) are the progenitors of myelinating oligodendrocytes in brain development and repair. Successful myelination depends on the control of adhesiveness during OPC migration and axon contact formation. The decoration of cell surface proteins with the glycan polysialic acid (polySia) is a key regulatory element of OPC interactions during development and under pathological conditions. By far the major protein carrier of polySia is the neural cell adhesion molecule NCAM, but recently, polysialylation of the synaptic cell adhesion molecule SynCAM 1 has been detected in the developing mouse brain. In mice, polySia-SynCAM 1 is associated with cells expressing NG2, a marker of a heterogeneous precursor cell population, which is the primary source for oligodendrocytes in development and myelin repair but can also give rise to astrocytes and possibly neurons. It is not yet clear if polySia-SynCAM 1 is expressed by OPCs and its occurrence in humans is elusive. By generating uniform human embryonic stem cell-derived OPC cultures, we demonstrate that polySia is present on human OPCs but down-regulated during differentiation into myelin basic protein-positive oligodendrocytes. PolySia on NCAM resides on the isoforms NCAM-180 and NCAM-140, and SynCAM 1 is identified as a novel polySia acceptor in human OPCs. Copyright © 2015. Published by Elsevier B.V.

  4. IKZF1 DELETIONS ARE INDEPENDENT PROGNOSTIC FACTOR IN PEDIATRIC B-CELL PRECURSOR ACUTE LYMPHOBLASTIC LEUKEMIA

    Directory of Open Access Journals (Sweden)

    G. A. Tsaur

    2016-01-01

    Full Text Available We assessed the prognostic significance of IKZF1 gene deletions in 141 pediatric patients with B-cell precursor acute lymphoblastic leukemia (BCP-ALL  on Russian multicenter trial in pediatric clinics of Ekaterinburg and Orenburg. IKZF1 deletions were estimated by multiplex ligation-dependent probe amplification. IKZF1 deletions were revealed in 15 (10.6 % patients. IKZF1 deletions were associated with age older than 10 years (p = 0.007, initial white blood cell count higher than 30 × 109/l (p = 0.003, t(9;22(q34.q11 (p = 0.003 and delayed blast clearance: М3 status of bone marrow at day 15 of remission induction (p = 0.003, lack of hematological remission at day 36 (p < 0.001 and high levels of minimal residual disease at days 15, 36 and 85 (p = 0.014; p < 0.001; p = 0.001 correspondingly. Patients with IKZF1 deletions had significantly lower event-free survival (EFS (0.30 ± 0.15 vs 0.89 ± 0.03; p < 0.001 and overall survival (OS (0.44 ± 0.19 vs 0.93 ± 0.02; p < 0.001, while cumulative incidence of relapse was higher (0.67 ± 0.18 vs 0.07 ± 0.02; p < 0.001. In the multivariate analysis IKZF1 deletions were associated with decreased EFS (hazard ratio (HR 4.755; 95 % confidence interval (CI 1.856–12.185; p = 0.001, and OS (HR 4.208; 95 % CI 1.322–13.393; p = 0.015, but increased relapse risk (HR 9,083; 95 % CI 3.119–26.451; p < 0.001. IKZF1 deletions retained their prognostic significance in the intermediate risk group patients (p < 0.001, but not in standard or high-risk groups. Majority of IKZF1 deletions – 12 (80 % of 15 – were revealed in the “B-other” group (n = 83. In this cohort of patients IKZF1 deletions led to inferior EFS (HR 6.172; 95 % CI 1.834–20.767; p = 0.003 and higher relapse rate (HR 16.303; 95 % CI 3.324–79.965; p = 0.015. Thus, our results showed that IKZF1 deletions are independent risk factor in BCP-ALL patients.

  5. An efficient copper phthalocyanine additive of perovskite precursor for improving the photovoltaic performance of planar perovskite solar cells

    Science.gov (United States)

    Wu, Shufang; Liu, Qingwei; Zheng, Ya; Li, Renjie; Peng, Tianyou

    2017-08-01

    Solution processable planar heterojunction perovskite solar cell has drawn much attention as a promising low-cost photovoltaic device, and much effort has been made to improve its power conversion efficiency by choosing appropriate additives for the perovskite precursor solution. Different to those additives reported, a soluble and thermal stable tert-butyl substituted copper phthalocyanine (CuPc(tBu)4) as additive is first introduced into the perovskite precursor solution of a planar perovskite solar cell that is fabricated via the one-step solution process. It is found that the pristine device without CuPc(tBu)4 additive exhibits a power conversion efficiency of 15.3%, while an extremely low concentration (4.4 × 10-3 mM) of CuPc(tBu)4 in the precursor solution leads to the corresponding device achieving an enhanced power conversion efficiency of 17.3%. CuPc(tBu)4 as an additive can improve the quality of perovskite layer with higher crystallinity and surface coverage, then resulting in enhanced light absorption and reduced charge recombination, and thus the better power conversion efficiency. The finding presented here provides a new choice for improving the quality of perovskite layer and the photovoltaic performance of the planar heterojunction perovskite solar cells.

  6. Transplantation of Photoreceptor Precursors Isolated via a Cell Surface Biomarker Panel From Embryonic Stem Cell-Derived Self-Forming Retina.

    Science.gov (United States)

    Lakowski, Jorn; Gonzalez-Cordero, Anai; West, Emma L; Han, Ya-Ting; Welby, Emily; Naeem, Arifa; Blackford, Samuel J I; Bainbridge, James W B; Pearson, Rachael A; Ali, Robin R; Sowden, Jane C

    2015-08-01

    Loss of photoreceptors due to retinal degeneration is a major cause of untreatable blindness. Cell replacement therapy, using pluripotent stem cell-derived photoreceptor cells, may be a feasible future treatment. Achieving safe and effective cell replacement is critically dependent on the stringent selection and purification of optimal cells for transplantation. Previously, we demonstrated effective transplantation of post-mitotic photoreceptor precursor cells labelled by fluorescent reporter genes. As genetically labelled cells are not desirable for therapy, here we developed a surface biomarker cell selection strategy for application to complex pluripotent stem cell differentiation cultures. We show that a five cell surface biomarker panel CD73(+)CD24(+)CD133(+)CD47(+)CD15(-) facilitates the isolation of photoreceptor precursors from three-dimensional self-forming retina differentiated from mouse embryonic stem cells. Importantly, stem cell-derived cells isolated using the biomarker panel successfully integrate and mature into new rod photoreceptors in the adult mouse retinae after subretinal transplantation. Conversely, unsorted or negatively selected cells do not give rise to newly integrated rods after transplantation. The biomarker panel also removes detrimental proliferating cells prior to transplantation. Notably, we demonstrate how expression of the biomarker panel is conserved in the human retina and propose that a similar selection strategy will facilitate isolation of human transplantation-competent cells for therapeutic application. © 2015 The Authors STEM CELLS published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

  7. Periostin associates with Notch1 precursor to maintain Notch1 expression under a stress condition in mouse cells.

    Directory of Open Access Journals (Sweden)

    Hideyuki Tanabe

    Full Text Available BACKGROUND: Matricellular proteins, including periostin, modulate cell-matrix interactions and cell functions by acting outside of cells. METHODS AND FINDINGS: In this study, however, we reported that periostin physically associates with the Notch1 precursor at its EGF repeats in the inside of cells. Moreover, by using the periodontal ligament of molar from periostin-deficient adult mice (Pn-/- molar PDL, which is a constitutively mechanically stressed tissue, we found that periostin maintained the site-1 cleaved 120-kDa transmembrane domain of Notch1 (N1 level without regulating Notch1 mRNA expression. N1 maintenance in vitro was also observed under such a stress condition as heat and H(2O(2 treatment in periostin overexpressed cells. Furthermore, we found that the expression of a downstream effector of Notch signaling, Bcl-xL was decreased in the Pn-/- molar PDL, and in the molar movement, cell death was enhanced in the pressure side of Pn-/- molar PDL. CONCLUSION: These results suggest the possibility that periostin inhibits cell death through up-regulation of Bcl-xL expression by maintaining the Notch1 protein level under the stress condition, which is caused by its physical association with the Notch1 precursor.

  8. Transplantation of adult mouse iPS cell-derived photoreceptor precursors restores retinal structure and function in degenerative mice.

    Directory of Open Access Journals (Sweden)

    Budd A Tucker

    2011-04-01

    Full Text Available This study was designed to determine whether adult mouse induced pluripotent stem cells (iPSCs, could be used to produce retinal precursors and subsequently photoreceptor cells for retinal transplantation to restore retinal function in degenerative hosts. iPSCs were generated using adult dsRed mouse dermal fibroblasts via retroviral induction of the transcription factors Oct4, Sox2, KLF4 and c-Myc. As with normal mouse ES cells, adult dsRed iPSCs expressed the pluripotency genes SSEA1, Oct4, Sox2, KLF4, c-Myc and Nanog. Following transplantation into the eye of immune-compromised retinal degenerative mice these cells proceeded to form teratomas containing tissue comprising all three germ layers. At 33 days post-differentiation a large proportion of the cells expressed the retinal progenitor cell marker Pax6 and went on to express the photoreceptor markers, CRX, recoverin, and rhodopsin. When tested using calcium imaging these cells were shown to exhibit characteristics of normal retinal physiology, responding to delivery of neurotransmitters. Following subretinal transplantation into degenerative hosts differentiated iPSCs took up residence in the retinal outer nuclear layer and gave rise to increased electro retinal function as determined by ERG and functional anatomy. As such, adult fibroblast-derived iPSCs provide a viable source for the production of retinal precursors to be used for transplantation and treatment of retinal degenerative disease.

  9. A brain slice culture model for studies of endogenous and exogenous precursor cell migration in the rostral migratory stream

    DEFF Research Database (Denmark)

    Tanvig, Mette; Blaabjerg, Morten; Andersen, Rikke K

    2009-01-01

    week old cultures. For testing the migratory abilities of exogenous precursor cells, rat SVZ neurospheres and human neural (HNS1 cells) and mesenchymal (hMSC-TERT) stem cell lines were micrografted to the rostral SVZ of 1 and 7 day old cultures. Two weeks later graft derivatives were identified......The rostral migratory stream (RMS) is the main pathway by which newly born subventricular zone (SVZ) cells reach the olfactory bulb (OB) in rodents. This migration has been well studied in vivo, but an organotypic in vitro model would facilitate more experimental investigations. Here we introduce...... a slice culture preparation of the rat forebrain including en suite the rostral part of the lateral ventricle, the RMS and the OB. The preparation was validated with regard to endogenous cell proliferation and migration by tracking bromodeoxyuridine (BrdU)-labelled cells in newly established and 3 and 6...

  10. Hybrid halide perovskite solar cell precursors: colloidal chemistry and coordination engineering behind device processing for high efficiency.

    Science.gov (United States)

    Yan, Keyou; Long, Mingzhu; Zhang, Tiankai; Wei, Zhanhua; Chen, Haining; Yang, Shihe; Xu, Jianbin

    2015-04-08

    The precursor of solution-processed perovskite thin films is one of the most central components for high-efficiency perovskite solar cells. We first present the crucial colloidal chemistry visualization of the perovskite precursor solution based on analytical spectra and reveal that perovskite precursor solutions for solar cells are generally colloidal dispersions in a mother solution, with a colloidal size up to the mesoscale, rather than real solutions. The colloid is made of a soft coordination complex in the form of a lead polyhalide framework between organic and inorganic components and can be structurally tuned by the coordination degree, thereby primarily determining the basic film coverage and morphology of deposited thin films. By utilizing coordination engineering, particularly through employing additional methylammonium halide over the stoichiometric ratio for tuning the coordination degree and mode in the initial colloidal solution, along with a thermal leaching for the selective release of excess methylammonium halides, we achieved full and even coverage, the preferential orientation, and high purity of planar perovskite thin films. We have also identified that excess organic component can reduce the colloidal size of and tune the morphology of the coordination framework in relation to final perovskite grains and partial chlorine substitution can accelerate the crystalline nucleation process of perovskite. This work demonstrates the important fundamental chemistry of perovskite precursors and provides genuine guidelines for accurately controlling the high quality of hybrid perovskite thin films without any impurity, thereby delivering efficient planar perovskite solar cells with a power conversion efficiency as high as 17% without distinct hysteresis owing to the high quality of perovskite thin films.

  11. High-efficiency perovskite solar cells prepared by using a sandwich structure MAI-PbI2-MAI precursor film.

    Science.gov (United States)

    Zhang, Xuhui; Ye, Jiajiu; Zhu, Liangzheng; Zheng, Haiying; Liu, Guozhen; Liu, Xuepeng; Duan, Bin; Pan, Xu; Dai, Songyuan

    2017-04-06

    Two-step deposition has been widely used in the perovskite layer preparation for perovskite solar cells due to its attractive morphology controllability. However, the limited diffusivity of CH 3 NH 3 I (MAI) might cause some PbI 2 to remain in the perovskite film. The residual PbI 2 in the perovskite film would lead to inferior performance of devices, such as, low power conversion efficiency (PCE), poor reproducibility and weak air stability. In this work, we developed a sandwich structure MAI-PbI 2 -MAI precursor film to prepare a PbI 2 -free CH 3 NH 3 PbI 3 perovskite film. In comparison to the two-step approach, the MAI-PbI 2 -MAI precursor film with a typical sandwich structure formed a uniform and pinhole-free perovskite film without any PbI 2 residue, which could significantly improve the performance of the devices. Moreover, the bottom MAI layer of the MAI-PbI 2 -MAI precursor film could improve the interfacial contact of the porous TiO 2 layer, leading to the promotion of the charge transfer and reduction of the recombination rate. Therefore, the devices fabricated from the sandwich structure MAI-PbI 2 -MAI precursor films showed dramatic improvements of open-circuit voltage (V oc ), short-circuit current density (J sc ), fill factor (FF) and PCE. As a result, a promising PCE of 17.8% with good long-term air stability was achieved for the MAI-PbI 2 -MAI precursor film based PSC, which is better than that prepared by a two-step approach.

  12. Novel Strategy for Phenotypic Characterization of Human B Lymphocytes from Precursors to Effector Cells by Flow Cytometry.

    Directory of Open Access Journals (Sweden)

    Giovanna Clavarino

    Full Text Available A precise identification and phenotypic characterization of human B-cell subsets is of crucial importance in both basic research and medicine. In the literature, flow cytometry studies for the phenotypic characterization of B-lymphocytes are mainly focused on the description of a particular cell stage, or of specific cell stages observed in a single type of sample. In the present work, we propose a backbone of 6 antibodies (CD38, CD27, CD10, CD19, CD5 and CD45 and an efficient gating strategy to identify, in a single analysis tube, a large number of B-cell subsets covering the whole B-cell differentiation from precursors to memory and plasma cells. Furthermore, by adding two antibodies in an 8-color combination, our approach allows the analysis of the modulation of any cell surface marker of interest along B-cell differentiation. We thus developed a panel of seven 8-colour antibody combinations to phenotypically characterize B-cell subpopulations in bone marrow, peripheral blood, lymph node and cord blood samples. Beyond qualitative information provided by biparametric representations, we also quantified antigen expression on each of the identified B-cell subsets and we proposed a series of informative curves showing the modulation of seventeen cell surface markers along B-cell differentiation. Our approach by flow cytometry provides an efficient tool to obtain quantitative data on B-cell surface markers expression with a relative easy-to-handle technique that can be applied in routine explorations.

  13. Expression of C4.4A in precursor lesions of pulmonary adenocarcinoma and squamous cell carcinoma

    DEFF Research Database (Denmark)

    Jacobsen, Benedikte; Santoni-Rugiu, Eric; Illemann, Martin

    2012-01-01

    The protein C4.4A, a structural homologue of the urokinase-type plasminogen activator receptor, is a potential new biomarker in non-small cell lung cancer, with high levels of expression recently shown to correlate to poor survival of adenocarcinoma patients. In this study, C4.4A immunoreactivity...... in precursor lesions of lung squamous cell carcinoma and adenocarcinoma was investigated by stainings with a specific anti-C4.4A antibody. In the transformation from normal bronchial epithelium to squamous cell carcinoma, C4.4A was weakly expressed in basal cell hyperplasia but dramatically increased...... finding that C4.4A expression levels do not provide prognostic information on the survival of squamous cell carcinoma patients. In the progression from normal alveolar epithelium to peripheral adenocarcinoma, we observed an unexpected, distinct cytoplasmic staining for C4.4A in a fraction of atypical...

  14. A gastrin precursor, gastrin-gly, upregulates VEGF expression in colonic epithelial cells through an HIF-1-independent mechanism

    Science.gov (United States)

    Bertrand, Claudine; Kowalski-Chauvel, Aline; Do, Catherine; Résa, Cécile; Najib, Souad; Daulhac, Laurence; Wang, Timothy C.; Ferrand, Audrey; Seva, Catherine

    2013-01-01

    One of the major angiogenic factor released by tumor cells is VEGF. Its high expression is correlated with poor prognosis in colorectal tumors. In colon cancer, gastrin gene expression is also upregulated. In these tumors, gastrin precursors are mainly produced and act as growth factors. Recently, a study has also shown that the gastrin precursor, G-gly induced in vitro tubules formation by vascular endothelial cells suggesting a potential proangiogenic role. Here, we demonstrate that stimulation of human colorectal cancer cell lines with G-gly increases the expression of the proangiogenic factor VEGF at the mRNA and protein levels. In addition, blocking the progastrin autocrine loop leads to a downregulation of VEGF. Although HIF-1 is a major transcriptional activator for VEGF our results suggest an alternative mechanism for VEGF regulation in normoxic conditions, independent of HIF-1 that involves the PI3K/AKT pathway. Indeed we show that G-gly does not lead to HIF-1 accumulation in colon cancer cells. Moreover, we found that G-gly activates the PI3K/AKT pathway and inhibition of this pathway reverses the effects of G-gly observed on VEGF mRNA and protein levels. In correlation with these results, we observed in vivo, on colon tissue sections from transgenic mice overexpressing G-gly, an increase in VEGF expression in absence of HIF-1 accumulation. In conclusion, our study demonstrates that gastrin precursors, known to promote colon epithelial cells proliferation and survival can also contribute to the angiogenesis process by stimulating the expression of the proangiogenic factor VEGF via the PI3K pathway and independently of hypoxia conditions. PMID:19876923

  15. Lamins and nesprin-1 mediate inside-out mechanical coupling in muscle cell precursors through FHOD1.

    Science.gov (United States)

    Schwartz, Christine; Fischer, Martina; Mamchaoui, Kamel; Bigot, Anne; Lok, Thevy; Verdier, Claude; Duperray, Alain; Michel, Richard; Holt, Ian; Voit, Thomas; Quijano-Roy, Suzanna; Bonne, Gisèle; Coirault, Catherine

    2017-04-28

    LINC complexes are crucial for the response of muscle cell precursors to the rigidity of their environment, but the mechanisms explaining this behaviour are not known. Here we show that pathogenic mutations in LMNA or SYNE-1 responsible for severe muscle dystrophies reduced the ability of human muscle cell precursors to adapt to substrates of different stiffness. Plated on muscle-like stiffness matrix, mutant cells exhibited contractile stress fibre accumulation, increased focal adhesions, and higher traction force than controls. Inhibition of Rho-associated kinase (ROCK) prevented cytoskeletal defects, while inhibiting myosin light chain kinase or phosphorylation of focal adhesion kinase was ineffective. Depletion or inactivation of a ROCK-dependent regulator of actin remodelling, the formin FHOD1, largely rescued morphology in mutant cells. The functional integrity of lamin and nesprin-1 is thus required to modulate the FHOD1 activity and the inside-out mechanical coupling that tunes the cell internal stiffness to match that of its soft, physiological-like environment.

  16. Transcriptional profiling of endogenous germ layer precursor cells identifies dusp4 as an essential gene in zebrafish endoderm specification

    Science.gov (United States)

    Brown, Jamie L.; Snir, Mirit; Noushmehr, Houtan; Kirby, Martha; Hong, Sung-Kook; Elkahloun, Abdel G.; Feldman, Benjamin

    2008-01-01

    A major goal for developmental biologists is to define the behaviors and molecular contents of differentiating cells. We have devised a strategy for isolating cells from diverse embryonic regions and stages in the zebrafish, using computer-guided laser photoconversion of injected Kaede protein and flow cytometry. This strategy enabled us to perform a genome-wide transcriptome comparison of germ layer precursor cells. Mesendoderm and ectoderm precursors cells isolated by this method differentiated appropriately in transplantation assays. Microarray analysis of these cells reidentified known genes at least as efficiently as previously reported strategies that relied on artificial mesendoderm activation or inhibition. We also identified a large set of uncharacterized mesendoderm-enriched genes as well as ectoderm-enriched genes. Loss-of-function studies revealed that one of these genes, the MAP kinase inhibitor dusp4, is essential for early development. Embryos injected with antisense morpholino oligonucleotides that targeted Dusp4 displayed necrosis of head tissues. Marker analysis during late gastrulation revealed a specific loss of sox17, but not of other endoderm markers, and analysis at later stages revealed a loss of foregut and pancreatic endoderm. This specific loss of sox17 establishes a new class of endoderm specification defect. PMID:18719100

  17. The role of Pitx2 in maintaining the phenotype of myogenic precursor cells in the extraocular muscles.

    Science.gov (United States)

    Hebert, Sadie L; Daniel, Mark L; McLoon, Linda K

    2013-01-01

    Many differences exist between extraocular muscles (EOM) and non-cranial skeletal muscles. One striking difference is the sparing of EOM in various muscular dystrophies compared to non-cranial skeletal muscles. EOM undergo continuous myonuclear remodeling in normal, uninjured adults, and distinct transcription factors are required for the early determination, development, and maintenance of EOM compared to limb skeletal muscle. Pitx2, a bicoid-like homeobox transcription factor, is required for the development of EOM and the maintenance of characteristic properties of the adult EOM phenotype, but is not required for the development of limb muscle. We hypothesize that these unique properties of EOM contribute to the constitutive differences between EOM and non-craniofacial skeletal muscles. Using flow cytometry, CD34(+)/Sca1(-/)CD45(-/)CD31(-) cells (EECD34 cells) were isolated from extraocular and limb skeletal muscle and in vitro, EOM EECD34 cells proliferated faster than limb muscle EECD34 cells. To further define these myogenic precursor cells from EOM and limb skeletal muscle, they were analyzed for their expression of Pitx2. Western blotting and immunohistochemical data demonstrated that EOM express higher levels of Pitx2 than limb muscle, and 80% of the EECD34 cells expressed Pitx2. siRNA knockdown of Pitx2 expression in EECD34 cells in vitro decreased proliferation rates and impaired the ability of EECD34 cells to fuse into multinucleated myotubes. High levels of Pitx2 were retained in dystrophic and aging mouse EOM and the EOM EECD34 cells compared to limb muscle. The differential expression of Pitx2 between EOM and limb skeletal muscle along with the functional changes in response to lower levels of Pitx2 expression in the myogenic precursor cells suggest a role for Pitx2 in the maintenance of constitutive differences between EOM and limb skeletal muscle that may contribute to the sparing of EOM in muscular dystrophies.

  18. The role of Pitx2 in maintaining the phenotype of myogenic precursor cells in the extraocular muscles.

    Directory of Open Access Journals (Sweden)

    Sadie L Hebert

    Full Text Available Many differences exist between extraocular muscles (EOM and non-cranial skeletal muscles. One striking difference is the sparing of EOM in various muscular dystrophies compared to non-cranial skeletal muscles. EOM undergo continuous myonuclear remodeling in normal, uninjured adults, and distinct transcription factors are required for the early determination, development, and maintenance of EOM compared to limb skeletal muscle. Pitx2, a bicoid-like homeobox transcription factor, is required for the development of EOM and the maintenance of characteristic properties of the adult EOM phenotype, but is not required for the development of limb muscle. We hypothesize that these unique properties of EOM contribute to the constitutive differences between EOM and non-craniofacial skeletal muscles. Using flow cytometry, CD34(+/Sca1(-/CD45(-/CD31(- cells (EECD34 cells were isolated from extraocular and limb skeletal muscle and in vitro, EOM EECD34 cells proliferated faster than limb muscle EECD34 cells. To further define these myogenic precursor cells from EOM and limb skeletal muscle, they were analyzed for their expression of Pitx2. Western blotting and immunohistochemical data demonstrated that EOM express higher levels of Pitx2 than limb muscle, and 80% of the EECD34 cells expressed Pitx2. siRNA knockdown of Pitx2 expression in EECD34 cells in vitro decreased proliferation rates and impaired the ability of EECD34 cells to fuse into multinucleated myotubes. High levels of Pitx2 were retained in dystrophic and aging mouse EOM and the EOM EECD34 cells compared to limb muscle. The differential expression of Pitx2 between EOM and limb skeletal muscle along with the functional changes in response to lower levels of Pitx2 expression in the myogenic precursor cells suggest a role for Pitx2 in the maintenance of constitutive differences between EOM and limb skeletal muscle that may contribute to the sparing of EOM in muscular dystrophies.

  19. Neuronal precursor cell proliferation in the hippocampus after transient cerebral ischemia: a comparative study of two rat strains using stereological tools

    DEFF Research Database (Denmark)

    Kelsen, Jesper; Larsen, Marianne; Sørensen, Jens Christian H.

    2010-01-01

    We are currently investigating microglial activation and neuronal precursor cell (NPC) proliferation after transient middle cerebral artery occlusion (tMCAo) in rats. This study aimed: (1) to investigate differences in hippocampal NPC proliferation in outbred male spontaneously hypertensive rats ...

  20. Genetic and epigenetic changes in vulvar squamous cell carcinoma and its precursor lesions: a review of the current literature.

    Science.gov (United States)

    Trietsch, Marjolijn D; Nooij, Linda S; Gaarenstroom, Katja N; van Poelgeest, Mariette I E

    2015-01-01

    Vulvar cancer is a relatively rare gynecologic malignancy with an annual incidence in developed countries of approximately 2 per 100,000 women. Vulvar squamous cell carcinoma (VSCC) has two etiological pathways: a high risk human papillomavirus (HPV)-dependent route, which has usual vulvar intraepithelial neoplasia (uVIN) as a precursor lesion, and an HPV-independent route, which is associated with differentiated VIN (dVIN), lichen sclerosus, and genetic alterations, such as TP53 mutations. Research on the molecular etiology of vulvar cancer has increased in the past years, not only regarding genetic alterations, but also epigenetic changes. In genetic alterations, a mutation irreversibly changes the nucleotide sequence of the DNA, or the number of copies of chromosomes per cell is altered. In epigenetics, the nucleotide sequence remains the same but genes can be 'switched' on or off by, for example, DNA methylation or histone modification. We searched the current literature on genetic and epigenetic alterations in VSCC and its precursor lesions. Many studies have reported a higher incidence of somatic mutations in HPV-negative tumors compared to HPV-positive tumors, with TP53 mutations being the most frequent. Allelic imbalances or loss of heterozygosity are more frequently found in higher stages of dysplasia and in invasive carcinomas, but it is not exclusive to HPV-negative tumors. A limited number of studies are available on epigenetic changes in vulvar lesions, with hypermethylation of CDKN2A being the most frequently investigated change. For most genes, hypermethylation occurs more frequently in vulvar squamous cell carcinomas than in precursor lesions. As most studies have focused on HPV infection and TP53 mutations, we suggest that more research should be performed using whole genome or next generation sequencing to determine the true landscape of genetic and epigenetic alterations in vulvar squamous cell carcinoma. Copyright © 2014 Elsevier Inc. All

  1. The Zebrafish Anillin-eGFP Reporter Marks Late Dividing Retinal Precursors and Stem Cells Entering Neuronal Lineages

    Science.gov (United States)

    Guglielmi, Luca; Patzel, Eva; Sel, Saadettin; Auffarth, Gerd U.; Carl, Matthias; Poggi, Lucia

    2017-01-01

    Monitoring cycling behaviours of stem and somatic cells in the living animal is a powerful tool to better understand tissue development and homeostasis. The tg(anillin:anillin-eGFP) transgenic line carries the full-length zebrafish F-actin binding protein Anillin fused to eGFP from a bacterial artificial chromosome (BAC) containing Anillin cis-regulatory sequences. Here we report the suitability of the Anillin-eGFP reporter as a direct indicator of cycling cells in the late embryonic and post-embryonic retina. We show that combining the anillin:anillin-eGFP with other transgenes such as ptf1a:dsRed and atoh7:gap-RFP allows obtaining spatial and temporal resolution of the mitotic potentials of specific retinal cell populations. This is exemplified by the analysis of the origin of the previously reported apically and non-apically dividing late committed precursors of the photoreceptor and horizontal cell layers. PMID:28107513

  2. A complex between contactin-1 and the protein tyrosine phosphatase PTPRZ controls the development of oligodendrocyte precursor cells

    Energy Technology Data Exchange (ETDEWEB)

    Lamprianou, Smaragda; Chatzopoulou, Elli; Thomas, Jean-Léon; Bouyain, Samuel; Harroch, Sheila (IP-Korea); (UPMC); (UMKC)

    2013-09-23

    The six members of the contactin (CNTN) family of neural cell adhesion molecules are involved in the formation and maintenance of the central nervous system (CNS) and have been linked to mental retardation and neuropsychiatric disorders such as autism. Five of the six CNTNs bind to the homologous receptor protein tyrosine phosphatases gamma (PTPRG) and zeta (PTPRZ), but the biological roles of these interactions remain unclear. We report here the cocrystal structure of the carbonic anhydrase-like domain of PTPRZ bound to tandem Ig repeats of CNTN1 and combine these structural data with binding assays to show that PTPRZ binds specifically to CNTN1 expressed at the surface of oligodendrocyte precursor cells. Furthermore, analyses of glial cell populations in wild-type and PTPRZ-deficient mice show that the binding of PTPRZ to CNTN1 expressed at the surface of oligodendrocyte precursor cells inhibits their proliferation and promotes their development into mature oligodendrocytes. Overall, these results implicate the PTPRZ/CNTN1 complex as a previously unknown modulator of oligodendrogenesis.

  3. Enhanced proliferation and dopaminergic differentiation of ventral mesencephalic precursor cells by synergistic effect of FGF2 and reduced oxygen tension

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, Pia [Department of Neurobiology Research, Institute of Molecular Medicine, University of Southern Denmark, Winslowparken 21, DK-5000 Odense C (Denmark); Department of Neurosurgery, University of Bern, CH-3010 Bern (Switzerland); Gramsbergen, Jan-Bert; Zimmer, Jens [Department of Neurobiology Research, Institute of Molecular Medicine, University of Southern Denmark, Winslowparken 21, DK-5000 Odense C (Denmark); Widmer, Hans R. [Department of Neurosurgery, University of Bern, CH-3010 Bern (Switzerland); Meyer, Morten, E-mail: MMeyer@health.sdu.dk [Department of Neurobiology Research, Institute of Molecular Medicine, University of Southern Denmark, Winslowparken 21, DK-5000 Odense C (Denmark)

    2011-07-15

    Effective numerical expansion of dopaminergic precursors might overcome the limited availability of transplantable cells in replacement strategies for Parkinson's disease. Here we investigated the effect of fibroblast growth factor-2 (FGF2) and FGF8 on expansion and dopaminergic differentiation of rat embryonic ventral mesencephalic neuroblasts cultured at high (20%) and low (3%) oxygen tension. More cells incorporated bromodeoxyuridine in cultures expanded at low as compared to high oxygen tension, and after 6 days of differentiation there were significantly more neuronal cells in low than in high oxygen cultures. Low oxygen during FGF2-mediated expansion resulted also in a significant increase in tyrosine hydroxylase-immunoreactive (TH-ir) dopaminergic neurons as compared to high oxygen tension, but no corresponding effect was observed for dopamine release into the culture medium. However, switching FGF2-expanded cultures from low to high oxygen tension during the last two days of differentiation significantly enhanced dopamine release and intracellular dopamine levels as compared to all other treatment groups. In addition, the short-term exposure to high oxygen enhanced in situ assessed TH enzyme activity, which may explain the elevated dopamine levels. Our findings demonstrate that modulation of oxygen tension is a recognizable factor for in vitro expansion and dopaminergic differentiation of rat embryonic midbrain precursor cells.

  4. Acute effects of wheel running on adult hippocampal precursor cells in mice are not caused by changes in cell cycle length or S phase length

    Directory of Open Access Journals (Sweden)

    Tim J. Fischer

    2014-10-01

    Full Text Available Exercise stimulates cellular brain plasticity by extending the pool of proliferating neural precursor cells in the adult hippocampus. This effect has been investigated extensively, but the most immediate cellular effect induced by exercise that results in this acute increase in the number of cycling cells remained unclear. In the developing brain as well as adult pathological models, cell cycle alterations have a major influence on the balance between proliferative and neurogenic divisions. In this study we investigated whether this might also apply to the acute physiological pro-neurogenic stimulus of physical exercise in adulthood. Do changes in cell cycle precede the measurable increase in proliferation? After 5 days of voluntary wheel running, however, we measured only a very small, statistically not significant acceleration in cell cycle, which could not quantitatively explain the observed increase in proliferating cells after exercise. Thus, at this acute stage, changes at the level of cell cycle control is not the primary causal mechanism for the expansion of the precursor cell population, although with time after the stimulus changes in cell cycle of the entire population of labeled cells might be the result of the expanded pool of cells that have progressed to the advanced neurogenic stages with shorter cell cycle length.

  5. Enhanced Performance of PbS-quantum-dot-sensitized Solar Cells via Optimizing Precursor Solution and Electrolytes

    Science.gov (United States)

    Tian, Jianjun; Shen, Ting; Liu, Xiaoguang; Fei, Chengbin; Lv, Lili; Cao, Guozhong

    2016-03-01

    This work reports a PbS-quantum-dot-sensitized solar cell (QDSC) with power conversion efficiency (PCE) of 4%. PbS quantum dots (QDs) were grown on mesoporous TiO2 film using a successive ion layer absorption and reaction (SILAR) method. The growth of QDs was found to be profoundly affected by the concentration of the precursor solution. At low concentrations, the rate-limiting factor of the crystal growth was the adsorption of the precursor ions, and the surface growth of the crystal became the limiting factor in the high concentration solution. The optimal concentration of precursor solution with respect to the quantity and size of synthesized QDs was 0.06 M. To further increase the performance of QDSCs, the 30% deionized water of polysulfide electrolyte was replaced with methanol to improve the wettability and permeability of electrolytes in the TiO2 film, which accelerated the redox couple diffusion in the electrolyte solution and improved charge transfer at the interfaces between photoanodes and electrolytes. The stability of PbS QDs in the electrolyte was also improved by methanol to reduce the charge recombination and prolong the electron lifetime. As a result, the PCE of QDSC was increased to 4.01%.

  6. PDGFRα(+) Cells in Embryonic Stem Cell Cultures Represent the In Vitro Equivalent of the Pre-implantation Primitive Endoderm Precursors.

    Science.gov (United States)

    Lo Nigro, Antonio; de Jaime-Soguero, Anchel; Khoueiry, Rita; Cho, Dong Seong; Ferlazzo, Giorgia Maria; Perini, Ilaria; Abon Escalona, Vanesa; Aranguren, Xabier Lopez; Chuva de Sousa Lopes, Susana M; Koh, Kian Peng; Conaldi, Pier Giulio; Hu, Wei-Shou; Zwijsen, An; Lluis, Frederic; Verfaillie, Catherine M

    2017-02-14

    In early mouse pre-implantation development, primitive endoderm (PrE) precursors are platelet-derived growth factor receptor alpha (PDGFRα) positive. Here, we demonstrated that cultured mouse embryonic stem cells (mESCs) express PDGFRα heterogeneously, fluctuating between a PDGFRα+ (PrE-primed) and a platelet endothelial cell adhesion molecule 1 (PECAM1)-positive state (epiblast-primed). The two surface markers can be co-detected on a third subpopulation, expressing epiblast and PrE determinants (double-positive). In vitro, these subpopulations differ in their self-renewal and differentiation capability, transcriptional and epigenetic states. In vivo, double-positive cells contributed to epiblast and PrE, while PrE-primed cells exclusively contributed to PrE derivatives. The transcriptome of PDGFRα(+) subpopulations differs from previously described subpopulations and shows similarities with early/mid blastocyst cells. The heterogeneity did not depend on PDGFRα but on leukemia inhibitory factor and fibroblast growth factor signaling and DNA methylation. Thus, PDGFRα(+) cells represent the in vitro counterpart of in vivo PrE precursors, and their selection from cultured mESCs yields pure PrE precursors. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  7. Value of liver elastography and abdominal ultrasound for detection of complications of allogeneic hemopoietic SCT.

    Science.gov (United States)

    Karlas, T; Weber, J; Nehring, C; Kronenberger, R; Tenckhoff, H; Mössner, J; Niederwieser, D; Tröltzsch, M; Lange, T; Keim, V

    2014-06-01

    Hepatic complications contribute to morbidity and mortality after allogeneic hemopoietic SCT. Liver Doppler ultrasound and elastography represent promising methods for pretransplant risk assessment and early detection of complications. Ultrasound (liver and spleen size, liver perfusion) and elastography (transient elastography (TE); right liver lobe acoustic radiation force impulse imaging (r-ARFI); left liver lobe ARFI (l-ARFI)) were prospectively evaluated in patients with indications for allo-SCT. Measurements were performed before and repeatedly after SCT. Results were compared with the incidence of life-threatening complications and death during the first 150 days after SCT. Of 59 included patients, 16 suffered from major complications and 9 of them died within the follow-up period. At baseline, liver and spleen size, liver perfusion, TE and r-ARFI did not differ significantly between patients with and without severe complications. In contrast, l-ARFI was significantly elevated in patients who later developed severe complications (1.58±0.30 m/s vs 1.37±0.27 m/s, P=0.030). After SCT, l-ARFI values remained elevated and TE showed increasing liver stiffness in patients with complications. The value of conventional liver ultrasound for prediction of severe SCT complications is limited. Increased values for TE and l-ARFI are associated with severe SCT complications and demand further evaluation.

  8. The effect of magnetic nanoparticles on neuronal differentiation of induced pluripotent stem cell-derived neural precursors

    Czech Academy of Sciences Publication Activity Database

    Jiráková, Klára; Šeneklová, Monika; Jirák, D.; Turnovcová, Karolína; Vosmanská, M.; Babič, Michal; Horák, Daniel; Veverka, Pavel; Jendelová, Pavla

    2016-01-01

    Roč. 11, č. 2016 (2016), s. 6267-6281 E-ISSN 1178-2013 R&D Projects: GA MŠk(CZ) LQ1604; GA MŠk(CZ) ED1.1.00/02.0109; GA MŠk(CZ) 7F14057 Institutional support: RVO:68378041 ; RVO:61389013 ; RVO:68378271 Keywords : neural precursors * magnetic resonance imaging * cell differentiation Subject RIV: FH - Neurology; EB - Genetics ; Molecular Biology (FGU-C); CD - Macromolecular Chemistry (UMCH-V) Impact factor: 4.300, year: 2016

  9. Atomic layer deposition precursor step repetition and surface plasma pretreatment influence on semiconductor–insulator–semiconductor heterojunction solar cell

    Energy Technology Data Exchange (ETDEWEB)

    Talkenberg, Florian, E-mail: florian.talkenberg@ipht-jena.de; Illhardt, Stefan; Schmidl, Gabriele; Schleusener, Alexander; Sivakov, Vladimir [Leibniz Institute of Photonic Technology, Albert-Einstein-Str. 9, D-07745 Jena (Germany); Radnóczi, György Zoltán; Pécz, Béla [Centre for Energy Research, Institute of Technical Physics and Materials Science, Konkoly-Thege Miklós u. 29-33, H-1121 Budapest (Hungary); Dikhanbayev, Kadyrjan; Mussabek, Gauhar [Department of Physics and Engineering, al-Farabi Kazakh National University, 71 al-Farabi Ave., 050040 Almaty (Kazakhstan); Gudovskikh, Alexander [Nanotechnology Research and Education Centre, St. Petersburg Academic University, Russian Academy of Sciences, Hlopina Str. 8/3, 194021 St. Petersburg (Russian Federation)

    2015-07-15

    Semiconductor–insulator–semiconductor heterojunction solar cells were prepared using atomic layer deposition (ALD) technique. The silicon surface was treated with oxygen and hydrogen plasma in different orders before dielectric layer deposition. A plasma-enhanced ALD process was applied to deposit dielectric Al{sub 2}O{sub 3} on the plasma pretreated n-type Si(100) substrate. Aluminum doped zinc oxide (Al:ZnO or AZO) was deposited by thermal ALD and serves as transparent conductive oxide. Based on transmission electron microscopy studies the presence of thin silicon oxide (SiO{sub x}) layer was detected at the Si/Al{sub 2}O{sub 3} interface. The SiO{sub x} formation depends on the initial growth behavior of Al{sub 2}O{sub 3} and has significant influence on solar cell parameters. The authors demonstrate that a hydrogen plasma pretreatment and a precursor dose step repetition of a single precursor improve the initial growth behavior of Al{sub 2}O{sub 3} and avoid the SiO{sub x} generation. Furthermore, it improves the solar cell performance, which indicates a change of the Si/Al{sub 2}O{sub 3} interface states.

  10. Impaired neurogenesis, learning and memory and low seizure threshold associated with loss of neural precursor cell survivin

    Directory of Open Access Journals (Sweden)

    Eisch Amelia

    2010-01-01

    Full Text Available Abstract Background Survivin is a unique member of the inhibitor of apoptosis protein (IAP family in that it exhibits antiapoptotic properties and also promotes the cell cycle and mediates mitosis as a chromosome passenger protein. Survivin is highly expressed in neural precursor cells in the brain, yet its function there has not been elucidated. Results To examine the role of neural precursor cell survivin, we first showed that survivin is normally expressed in periventricular neurogenic regions in the embryo, becoming restricted postnatally to proliferating and migrating NPCs in the key neurogenic sites, the subventricular zone (SVZ and the subgranular zone (SGZ. We then used a conditional gene inactivation strategy to delete the survivin gene prenatally in those neurogenic regions. Lack of embryonic NPC survivin results in viable, fertile mice (SurvivinCamcre with reduced numbers of SVZ NPCs, absent rostral migratory stream, and olfactory bulb hypoplasia. The phenotype can be partially rescued, as intracerebroventricular gene delivery of survivin during embryonic development increases olfactory bulb neurogenesis, detected postnatally. SurvivinCamcre brains have fewer cortical inhibitory interneurons, contributing to enhanced sensitivity to seizures, and profound deficits in memory and learning. Conclusions The findings highlight the critical role that survivin plays during neural development, deficiencies of which dramatically impact on postnatal neural function.

  11. IAP-Based Cell Sorting Results in Homogeneous Transplantable Dopaminergic Precursor Cells Derived from Human Pluripotent Stem Cells

    Directory of Open Access Journals (Sweden)

    Daniela Lehnen

    2017-10-01

    Full Text Available Human pluripotent stem cell (hPSC-derived mesencephalic dopaminergic (mesDA neurons can relieve motor deficits in animal models of Parkinson's disease (PD. Clinical translation of differentiation protocols requires standardization of production procedures, and surface-marker-based cell sorting is considered instrumental for reproducible generation of defined cell products. Here, we demonstrate that integrin-associated protein (IAP is a cell surface marker suitable for enrichment of hPSC-derived mesDA progenitor cells. Immunomagnetically sorted IAP+ mesDA progenitors showed increased expression of ventral midbrain floor plate markers, lacked expression of pluripotency markers, and differentiated into mature dopaminergic (DA neurons in vitro. Intrastriatal transplantation of IAP+ cells sorted at day 16 of differentiation in a rat model of PD resulted in functional recovery. Grafts from sorted IAP+ mesDA progenitors were more homogeneous in size and DA neuron density. Thus, we suggest IAP-based sorting for reproducible prospective enrichment of mesDA progenitor cells in clinical cell replacement strategies.

  12. Immature MEF2C-dysregulated T-cell leukemia patients have an early T-cell precursor acute lymphoblastic leukemia gene signature and typically have non-rearranged T-cell receptors

    Science.gov (United States)

    Zuurbier, Linda; Gutierrez, Alejandro; Mullighan, Charles G.; Canté-Barrett, Kirsten; Gevaert, A. Olivier; de Rooi, Johan; Li, Yunlei; Smits, Willem K.; Buijs-Gladdines, Jessica G.C.A.M.; Sonneveld, Edwin; Look, A. Thomas; Horstmann, Martin; Pieters, Rob; Meijerink, Jules P.P.

    2014-01-01

    Three distinct immature T-cell acute lymphoblastic leukemia entities have been described including cases that express an early T-cell precursor immunophenotype or expression profile, immature MEF2C-dysregulated T-cell acute lymphoblastic leukemia cluster cases based on gene expression analysis (immature cluster) and cases that retain non-rearranged TRG@ loci. Early T-cell precursor acute lymphoblastic leukemia cases exclusively overlap with immature cluster samples based on the expression of early T-cell precursor acute lymphoblastic leukemia signature genes, indicating that both are featuring a single disease entity. Patients lacking TRG@ rearrangements represent only 40% of immature cluster cases, but no further evidence was found to suggest that cases with absence of bi-allelic TRG@ deletions reflect a distinct and even more immature disease entity. Immature cluster/early T-cell precursor acute lymphoblastic leukemia cases are strongly enriched for genes expressed in hematopoietic stem cells as well as genes expressed in normal early thymocyte progenitor or double negative-2A T-cell subsets. Identification of early T-cell precursor acute lymphoblastic leukemia cases solely by defined immunophenotypic criteria strongly underestimates the number of cases that have a corresponding gene signature. However, early T-cell precursor acute lymphoblastic leukemia samples correlate best with a CD1 negative, CD4 and CD8 double negative immunophenotype with expression of CD34 and/or myeloid markers CD13 or CD33. Unlike various other studies, immature cluster/early T-cell precursor acute lymphoblastic leukemia patients treated on the COALL-97 protocol did not have an overall inferior outcome, and demonstrated equal sensitivity levels to most conventional therapeutic drugs compared to other pediatric T-cell acute lymphoblastic leukemia patients. PMID:23975177

  13. Regulation of Neurod1 contributes to the lineage potential of Neurogenin3+ endocrine precursor cells in the pancreas.

    Science.gov (United States)

    Mastracci, Teresa L; Anderson, Keith R; Papizan, James B; Sussel, Lori

    2013-01-01

    During pancreatic development, transcription factor cascades gradually commit precursor populations to the different endocrine cell fate pathways. Although mutational analyses have defined the functions of many individual pancreatic transcription factors, the integrative transcription factor networks required to regulate lineage specification, as well as their sites of action, are poorly understood. In this study, we investigated where and how the transcription factors Nkx2.2 and Neurod1 genetically interact to differentially regulate endocrine cell specification. In an Nkx2.2 null background, we conditionally deleted Neurod1 in the Pdx1+ pancreatic progenitor cells, the Neurog3+ endocrine progenitor cells, or the glucagon+ alpha cells. These studies determined that, in the absence of Nkx2.2 activity, removal of Neurod1 from the Pdx1+ or Neurog3+ progenitor populations is sufficient to reestablish the specification of the PP and epsilon cell lineages. Alternatively, in the absence of Nkx2.2, removal of Neurod1 from the Pdx1+ pancreatic progenitor population, but not the Neurog3+ endocrine progenitor cells, restores alpha cell specification. Subsequent in vitro reporter assays demonstrated that Nkx2.2 represses Neurod1 in alpha cells. Based on these findings, we conclude that, although Nkx2.2 and Neurod1 are both necessary to promote beta cell differentiation, Nkx2.2 must repress Neurod1 in a Pdx1+ pancreatic progenitor population to appropriately commit a subset of Neurog3+ endocrine progenitor cells to the alpha cell lineage. These results are consistent with the proposed idea that Neurog3+ endocrine progenitor cells represent a heterogeneous population of unipotent cells, each restricted to a particular endocrine lineage.

  14. Regulation of Neurod1 contributes to the lineage potential of Neurogenin3+ endocrine precursor cells in the pancreas.

    Directory of Open Access Journals (Sweden)

    Teresa L Mastracci

    Full Text Available During pancreatic development, transcription factor cascades gradually commit precursor populations to the different endocrine cell fate pathways. Although mutational analyses have defined the functions of many individual pancreatic transcription factors, the integrative transcription factor networks required to regulate lineage specification, as well as their sites of action, are poorly understood. In this study, we investigated where and how the transcription factors Nkx2.2 and Neurod1 genetically interact to differentially regulate endocrine cell specification. In an Nkx2.2 null background, we conditionally deleted Neurod1 in the Pdx1+ pancreatic progenitor cells, the Neurog3+ endocrine progenitor cells, or the glucagon+ alpha cells. These studies determined that, in the absence of Nkx2.2 activity, removal of Neurod1 from the Pdx1+ or Neurog3+ progenitor populations is sufficient to reestablish the specification of the PP and epsilon cell lineages. Alternatively, in the absence of Nkx2.2, removal of Neurod1 from the Pdx1+ pancreatic progenitor population, but not the Neurog3+ endocrine progenitor cells, restores alpha cell specification. Subsequent in vitro reporter assays demonstrated that Nkx2.2 represses Neurod1 in alpha cells. Based on these findings, we conclude that, although Nkx2.2 and Neurod1 are both necessary to promote beta cell differentiation, Nkx2.2 must repress Neurod1 in a Pdx1+ pancreatic progenitor population to appropriately commit a subset of Neurog3+ endocrine progenitor cells to the alpha cell lineage. These results are consistent with the proposed idea that Neurog3+ endocrine progenitor cells represent a heterogeneous population of unipotent cells, each restricted to a particular endocrine lineage.

  15. Hnf6 and Tcf2 (MODY5) are linked in a gene network operating in a precursor cell domain of the embryonic pancreas.

    Science.gov (United States)

    Maestro, Miguel A; Boj, Sylvia F; Luco, Reini F; Pierreux, Christophe E; Cabedo, Judit; Servitja, Joan M; German, Michael S; Rousseau, Guy G; Lemaigre, Frederic P; Ferrer, Jorge

    2003-12-15

    During pancreatic organogenesis endocrine cells arise from non self-renewing progenitors that express Ngn3. The precursors that give rise to Ngn3+ cells are presumably located within duct-like structures. However, the nature of such precursors is poorly understood. We show that, at E13-E18, the embryonic stage during which the major burst of beta-cell neogenesis takes place, pancreatic duct cells express Hnf1beta, the product of the maturity-onset diabetes of the young type 5 (MODY5) gene. Ngn3+ cells at this stage invariably cluster with mitotically competent Hnf1beta+ cells, and are often intercalated with these cells in the epithelium that lines the lumen of primitive ducts. We present several observations that collectively indicate that Hnf1beta+ cells are the immediate precursors of Ngn3+ cells. We furthermore show that Hnf1beta expression is markedly reduced in early pancreatic epithelial cells of Hnf6-deficient mice, in which formation of Ngn3+ cells is defective. These findings define a precursor cellular stage of the embryonic pancreas and place Hnf1beta in a genetic hierarchy that regulates the generation of pancreatic endocrine cells.

  16. Robust regeneration of adult zebrafish lateral line hair cells reflects continued precursor pool maintenance.

    Science.gov (United States)

    Cruz, Ivan A; Kappedal, Ryan; Mackenzie, Scott M; Hailey, Dale W; Hoffman, Trevor L; Schilling, Thomas F; Raible, David W

    2015-06-15

    We have examined lateral line hair cell and support cell maintenance in adult zebrafish when growth is largely complete. We demonstrate that adult zebrafish not only replenish hair cells after a single instance of hair cell damage, but also maintain hair cells and support cells after multiple rounds of damage and regeneration. We find that hair cells undergo continuous turnover in adult zebrafish in the absence of damage. We identify mitotically-distinct support cell populations and show that hair cells regenerate from underlying support cells in a region-specific manner. Our results demonstrate that there are two distinct support cell populations in the lateral line, which may help explain why zebrafish hair cell regeneration is extremely robust, retained throughout life, and potentially unlimited in regenerative capacity. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Receiver operating characteristic curve analysis of circulating blood dendritic cell precursors and T cells predicts response to extracorporeal photopheresis in patients with chronic graft-versus-host disease.

    Science.gov (United States)

    Akhtari, Mojtaba; Giver, Cynthia R; Ali, Zahir; Flowers, Christopher R; Gleason, Charise L; Hillyer, Christopher D; Kaufman, Jonathan; Khoury, H Jean; Langston, Amelia A; Lechowicz, Mary Jo; Lonial, Sagar; Renfroe, Heather M; Roback, John D; Tighiouart, Mourad; Vaughn, Louette; Waller, Edmund K

    2010-11-01

    One proposed mechanism of extracorporeal photopheresis (ECP) in reducing chronic graft-versus-host disease (cGVHD) is alteration in numbers of circulating dendritic cells (DCs). This hypothesis was tested by correlating numbers of DC precursors and T cells in the blood before and during ECP therapy with response of cGVHD. Twenty-five patients with cGVHD were treated with ECP. Data were collected with emphasis on blood cellular markers, clinical response to ECP, and overall survival. Fourteen patients (56%) responded and had better 2-year survival than nonresponders (88% vs. 18%, p=0.003). Responders had higher baseline circulating myeloid DC (mDC) and plasmacytoid DC precursors and CD4+ and CD8+ T cells compared with nonresponders. Receiver operating characteristic curve analyses showed that the best baseline cutoff values to predict response to ECP were mDC counts of 3.7 cells/µL (79% sensitivity, 82% specificity) and CD4+ T-cell counts of 104 cells/µL (71% sensitivity, 82% specificity). CD4+ T cells declined in responders over time, but not in nonresponders, and no significant changes were seen in CD8 T-cell or DC numbers over a 12-month period in responder or nonresponder groups. Higher baseline numbers of circulating DCs and T cells may predict clinical response to ECP in patients with cGVHD. © 2010 American Association of Blood Banks.

  18. Successful Vaccination Induces Multifunctional Memory T-Cell Precursors Associated with Early Control of Hepatitis C Virus

    Science.gov (United States)

    Park, Su-Hyung; Shin, Eui-Cheol; Capone, Stefania; Caggiari, Laura; De Re, Valli; Nicosia, Alfredo; Folgori, Antonella; Rehermann, Barbara

    2012-01-01

    Background & Aims T cells are an important component for development of a vaccine against hepatitis C virus (HCV), but little is known about the features of successful vaccine-induced T cells. Methods We compared the phenotype, function, and kinetics of vaccine-induced and infection-induced T cells in chimpanzees with HCV infection using multicolor flow cytometry and real-time PCR. Results In chimpanzees successfully vaccinated with recombinant adenovirus and DNA against HCV NS3-NS5, HCV-specific T cells appeared earlier, maintained better functionality, and persisted at higher frequencies, for a longer time after HCV-challenge, than those of mock-vaccinated chimpanzees. Vaccine-induced T cells displayed higher levels of CD127, a marker of memory precursors, and lower levels of programmed death (PD)-1 than infection-induced T cells. Vaccine-induced, but not infection-induced T cells, were multifunctional; their ability to secrete interferon-γ and tumor necrosis factor-α correlated with early expression of CD127 but not PD-1. Based on a comparison of vaccine-induced and infection-induced T cells from the same chimpanzee, the CD127+ memory precursor phenotype was induced by the vaccine itself, rather than by low viremia. In contrast, PD-1 induction correlated with viremia, and levels of intrahepatic PD-1, PD-L1, and 2,5-OAS-1 mRNAs correlated with peak titers of HCV. Conclusions Compared with infection, vaccination induced HCV-specific CD127+ T cells with high functionality that persisted at higher levels for a longer time. Control of viremia prevented upregulation of PD-1 on T cells, and induction of PD-1, PD-L1, and 2,5-OAS-1 in the liver. Early development of a memory T-cell phenotype and, via control of viremia, attenuation of the inhibitory PD1–PD-L1 pathway might be necessary components of successful vaccine-induced protection against HCV. PMID:22705008

  19. [Systemic lymphoma cells with T precursor condition of extreme female genital tract. A case report and literature review].

    Science.gov (United States)

    Butrón Valdez, Karla; Ramírez Galves, Miguel; Germes Piña, Fernando; Ramos Martínez, Ernesto; Zamora Perea, Arturo

    2009-06-01

    Primary female genital tract non Hodgkin's lymphoma is a rare presentation for a common disease in the childhood, and its classification as primary extranodal lymphoma is still controversial. There are a few cases reported as a primary precursor B-cell lymphoblastic lymphoma of the female genital tract, but there is not any case reported as primary precursor T-cell lymphoblastic lymphoma of the ovary in childhood. Herein we describe a 16 years old young woman with bilateral ovarian tumors, paraaortic lymphoadenophaty and disseminate disease to the female genital tract including extension of the tumor to neighboring organs like the omentum and the appendix. Exploratory laparatomy were performed with bilateral salpingo-oophorectomy, hysterectomy, omentectomy, appendectomy, pelvic and para-aortic lymphadenectomy, pelvic washings and with biopsy of vaginal vault. The chemotherapy regimen comprised of CHOP (Cyclophosphamide, Hydroxydaunorubicin, Oncovin, Prednisone/Prednisolone) and methotrexate, 3 months later presents left facial hemiparesia follow by right facial hemiparesia, 7 months later presents more Central Nervous System (CNS) complications and apparently was complicated with acute lymphocitic leukemia and after 16 months from the diagnosis, following by a torpid evolution, the pacient finally died.

  20. Nuclear factor-I regulates glial fibrillary acidic protein gene expression in astrocytes differentiated from cortical precursor cells.

    Science.gov (United States)

    Cebolla, Beatriz; Vallejo, Mario

    2006-05-01

    The elucidation of the transcriptional mechanisms that regulate glial fibrillary acidic protein (GFAP) gene expression is important for the understanding of the molecular mechanisms that control astrocyte differentiation during brain development. We investigated regulatory elements located in a proximal region of the GFAP promoter, important for expression in cortical precursor cells differentiating into astrocytes. One of these elements recognizes transcription factors of the nuclear factor-I family (NFI). We found that, in primary cultures of cortical cells, NFI occupies the GFAP promoter prior to the induction of astrocyte differentiation. In the developing cerebral cortex, the onset of expression of NFI coincides chronologically with the beginning of astrocytogenesis. Mutational analysis of the GFAP gene and transfections in primary cortical precursors show that inhibition of binding of NFI to the GFAP promoter results in decreased levels of transcriptional activity and is required for the synergistic stimulation of the GFAP promoter by the astrogenic agents, pituitary adenylate cyclase-activating polypeptide and ciliary neurotrophic factor, which in combination enhance astrocyte differentiation to generate astrocytes with longer processes. Thus, NFI appears to be an important factor for the integration of astrogenic stimuli in the developing central nervous system.

  1. gone early, a novel germline factor, ensures the proper size of the stem cell precursor pool in the Drosophila ovary.

    Directory of Open Access Journals (Sweden)

    Shinya Matsuoka

    Full Text Available In order to sustain lifelong production of gametes, many animals have evolved a stem cell-based gametogenic program. In the Drosophila ovary, germline stem cells (GSCs arise from a pool of primordial germ cells (PGCs that remain undifferentiated even after gametogenesis has initiated. The decision of PGCs to differentiate or remain undifferentiated is regulated by somatic stromal cells: specifically, epidermal growth factor receptor (EGFR signaling activated in the stromal cells determines the fraction of germ cells that remain undifferentiated by shaping a Decapentaplegic (Dpp gradient that represses PGC differentiation. However, little is known about the contribution of germ cells to this process. Here we show that a novel germline factor, Gone early (Goe, limits the fraction of PGCs that initiate gametogenesis. goe encodes a non-peptidase homologue of the Neprilysin family metalloendopeptidases. At the onset of gametogenesis, Goe was localized on the germ cell membrane in the ovary, suggesting that it functions in a peptidase-independent manner in cell-cell communication at the cell surface. Overexpression of Goe in the germline decreased the number of PGCs that enter the gametogenic pathway, thereby increasing the proportion of undifferentiated PGCs. Inversely, depletion of Goe increased the number of PGCs initiating differentiation. Excess PGC differentiation in the goe mutant was augmented by halving the dose of argos, a somatically expressed inhibitor of EGFR signaling. This increase in PGC differentiation resulted in a massive decrease in the number of undifferentiated PGCs, and ultimately led to insufficient formation of GSCs. Thus, acting cooperatively with a somatic regulator of EGFR signaling, the germline factor goe plays a critical role in securing the proper size of the GSC precursor pool. Because goe can suppress EGFR signaling activity and is expressed in EGF-producing cells in various tissues, goe may function by attenuating

  2. Human Müller Glia with Stem Cell Characteristics Differentiate into Retinal Ganglion Cell (RGC) Precursors In Vitro and Partially Restore RGC Function In Vivo Following Transplantation

    OpenAIRE

    Singhal, Shweta; Bhatia, Bhairavi; Jayaram, Hari; Becker, Silke; Jones, Megan F.; Cottrill, Phillippa B.; Khaw, Peng T.; Salt, Thomas E.; Limb, G. Astrid

    2012-01-01

    Müller glia with stem cell characteristics have been identified in the adult human eye, and although there is no evidence that they regenerate retina in vivo, they can be induced to grow and differentiate into retinal neurons in vitro. We differentiated human Müller stem cells into retinal ganglion cell (RGC) precursors by stimulation with fibroblast growth factor 2 together with NOTCH inhibition using the γ-secretase inhibitor N-[N-(3,5-difluorophenacetyl)-l-alanyl]-S-phenylglycine t-butyl e...

  3. N-methyl-D-aspartate receptors in human erythroid precursor cells and in circulating red blood cells contribute to the intracellular calcium regulation.

    Science.gov (United States)

    Makhro, Asya; Hänggi, Pascal; Goede, Jeroen S; Wang, Jue; Brüggemann, Andrea; Gassmann, Max; Schmugge, Markus; Kaestner, Lars; Speer, Oliver; Bogdanova, Anna

    2013-12-01

    The presence of N-methyl-d-aspartate receptor (NMDAR) was previously shown in rat red blood cells (RBCs) and in a UT-7/Epo human myeloid cell line differentiating into erythroid lineage. Here we have characterized the subunit composition of the NMDAR and monitored its function during human erythropoiesis and in circulating RBCs. Expression of the NMDARs subunits was assessed in erythroid progenitors during ex vivo erythropoiesis and in circulating human RBCs using quantitative PCR and flow cytometry. Receptor activity was monitored using a radiolabeled antagonist binding assay, live imaging of Ca(2+) uptake, patch clamp, and monitoring of cell volume changes. The receptor tetramers in erythroid precursor cells are composed of the NR1, NR2A, 2C, 2D, NR3A, and 3B subunits of which the glycine-binding NR3A and 3B and glutamate-binding NR2C and 2D subunits prevailed. Functional receptor is required for survival of erythroid precursors. Circulating RBCs retain a low number of the receptor copies that is higher in young cells compared with mature and senescent RBC populations. In circulating RBCs the receptor activity is controlled by plasma glutamate and glycine. Modulation of the NMDAR activity in RBCs by agonists or antagonists is associated with the alterations in whole cell ion currents. Activation of the receptor results in the transient Ca(2+) accumulation, cell shrinkage, and alteration in the intracellular pH, which is associated with the change in hemoglobin oxygen affinity. Thus functional NMDARs are present in erythroid precursor cells and in circulating RBCs. These receptors contribute to intracellular Ca(2+) homeostasis and modulate oxygen delivery to peripheral tissues.

  4. Rapid transgene expression in multiple precursor cell types of adult rat subventricular zone mediated by adeno-associated type 1 vectors.

    Science.gov (United States)

    Bockstael, Olivier; Melas, Catherine; Pythoud, Catherine; Levivier, Marc; McCarty, Douglas; Samulski, R Jude; De Witte, Olivier; Tenenbaum, Liliane

    2012-07-01

    The adult rat brain subventricular zone (SVZ) contains proliferative precursors that migrate to the olfactory bulb (OB) and differentiate into mature neurons. Recruitment of precursors constitutes a potential avenue for brain repair. We have investigated the kinetics and cellular specificity of transgene expression mediated by AAV2/1 vectors (i.e., adeno-associated virus type 2 pseudotyped with AAV1 capsid) in the SVZ. Self-complementary (sc) and single-stranded (ss) AAV2/1 vectors mediated efficient GFP expression, respectively, at 17 and 24 hr postinjection. Transgene expression was efficient in all the rapidly proliferating cells types, that is, Mash1(+) precursors (30% of the GFP(+) cells), Dlx2(+) neuronal progenitors (55%), Olig2(+) oligodendrocyte progenitors (35%), and doublecortin-positive (Dcx(+)) migrating cells (40%), but not in the slowly proliferating glial fibrillary acidic protein-positive (GFAP(+)) neural stem cell pool (5%). Because cell cycle arrest by wild-type and recombinant AAV has been described in primary cultures, we examined SVZ proliferative activity after vector injection. Indeed, cell proliferation was reduced immediately after vector injection but was normal after 1 month. In contrast, migration and differentiation of GFP(+) precursors were unaltered. Indeed, the proportion of Dcx(+) cells was similar in the injected and contralateral hemispheres. Furthermore, 1 month after vector injection into the SVZ, GFP(+) cells, found, as expected, in the OB granular cell layer, were mature GABAergic neurons. In conclusion, the rapid and efficient transgene expression in SVZ neural precursors mediated by scAAV2/1 vectors underlines their potential usefulness for brain repair via recruitment of immature cells. The observed transient precursor proliferation inhibition, not affecting their migration and differentiation, will likely not compromise this strategy.

  5. The formation of CuInSe{sub 2}-based thin-film solar cell absorbers from alternative low-cost precursors

    Energy Technology Data Exchange (ETDEWEB)

    Jost, S.

    2008-01-18

    This work deals with real-time investigations concerning the crystallisation process of CuInSe{sub 2}-based thin-film solar cell absorbers while annealing differently produced and composed ''low-cost'' precursors. Various types of precursors have been investigated concerning their crystallisation behaviour. Three groups of experiments have been performed: (i) Investigations concerning the crystallisation process of the quaternary chalcopyrite Cu(In,Al)Se{sub 2} and Cu(In,Al)S{sub 2}, (ii) investigations concerning the formation process of the compound semiconductor CuInSe{sub 2} from electroplated precursors, and (iii) investigations concerning the crystallisation of Cu(In,Ga)Se{sub 2} using precursors with thermally evaporated indium. A specific sample surrounding has been constructed, which enables to perform time-resolved angle-dispersive X-ray powder diffraction experiments during the annealing process of precursor samples. A thorough analysis of subsequently recorded diffraction patterns using the Rietveld method provides a detailed knowledge about the semiconductor crystallisation process while annealing. Based on these fundamental investigations, conclusions have been drawn concerning an adaptation of the precursor deposition process in order to optimise the final solar cell results. The investigations have shown, that one class of electroplated precursors shows a crystallisation behaviour identical to the one known for vacuum-deposited precursors. The investigations concerning the crystallisation process of the quaternary chalcopyrite Cu(In,Al)Se{sub 2} revealed, that the chalcopyrite forms from the ternary selenide (Al,In){sub 2}Se{sub 3} and Cu{sub 2}Se at elevated process temperatures. This result is used to explain the separation of the absorber layer into an aluminum-rich and an indium-rich chalcopyrite phase, which has been observed at processed Cu(In,Al)Se{sub 2} absorbers from several research groups. In addition, differences

  6. Phenotypic Screening Identifies Modulators of Amyloid Precursor Protein Processing in Human Stem Cell Models of Alzheimer’s Disease

    Directory of Open Access Journals (Sweden)

    Philip W. Brownjohn

    2017-04-01

    Full Text Available Human stem cell models have the potential to provide platforms for phenotypic screens to identify candidate treatments and cellular pathways involved in the pathogenesis of neurodegenerative disorders. Amyloid precursor protein (APP processing and the accumulation of APP-derived amyloid β (Aβ peptides are key processes in Alzheimer's disease (AD. We designed a phenotypic small-molecule screen to identify modulators of APP processing in trisomy 21/Down syndrome neurons, a complex genetic model of AD. We identified the avermectins, commonly used as anthelmintics, as compounds that increase the relative production of short Aβ peptides at the expense of longer, potentially more toxic peptides. Further studies demonstrated that this effect is not due to an interaction with the core γ-secretase responsible for Aβ production. This study demonstrates the feasibility of phenotypic drug screening in human stem cell models of Alzheimer-type dementia, and points to possibilities for indirectly modulating APP processing, independently of γ-secretase modulation.

  7. Skin-Derived Precursor Cells as an In Vitro Modelling Tool for the Study of Type 1 Neurofibromatosis

    Directory of Open Access Journals (Sweden)

    Araika Gutiérrez-Rivera

    2012-01-01

    Full Text Available The most characteristic feature of neurofibromatosis type 1 (NF1 is the development of neurofibromas. It has been suggested that these tumors are caused by somatic inactivation of the wild-type NF1 allele, but the cell that originally suffers this mutation remains controversial. Several lines of evidence support the clonal origin of these tumors, and it has been recently suggested that skin-derived precursor cells (SKPs could be the cell of origin of dermal neurofibromas. Nullizygous (NF1−/− SKPs do give rise to neurofibromas when transplanted to heterozygous mice. Moreover, a nullizygous population of cells that is S100β negative is present in human neurofibromas, and NF1+/− multipotent progenitor cells are seemingly recruited to the tumor. This evidence supports the neurofibroma stem cell hypothesis and a putative involvement of SKPs in the aetiopathogenesis of the disease, suggesting that SKPs could become a valuable tool for the in vitro study of NF1.

  8. Specifically modified Env immunogens activate B-cell precursors of broadly neutralizing HIV-1 antibodies in transgenic mice

    Science.gov (United States)

    McGuire, Andrew T.; Gray, Matthew D.; Dosenovic, Pia; Gitlin, Alexander D.; Freund, Natalia T.; Petersen, John; Correnti, Colin; Johnsen, William; Kegel, Robert; Stuart, Andrew B.; Glenn, Jolene; Seaman, Michael S.; Schief, William R.; Strong, Roland K.; Nussenzweig, Michel C.; Stamatatos, Leonidas

    2016-01-01

    VRC01-class broadly neutralizing HIV-1 antibodies protect animals from experimental infection and could contribute to an effective vaccine response. Their predicted germline forms (gl) bind Env inefficiently, which may explain why they are not elicited by HIV-1 Env-immunization. Here we show that an optimized Env immunogen can engage multiple glVRC01-class antibodies. Furthermore, this immunogen activates naive B cells expressing the human germline heavy chain of 3BNC60, paired with endogenous mouse light chains in vivo. To address whether it activates B cells expressing the fully humanized gl3BNC60 B-cell receptor (BCR), we immunized mice carrying both the heavy and light chains of gl3BNC60. B cells expressing this BCR display an autoreactive phenotype and fail to respond efficiently to soluble forms of the optimized immunogen, unless it is highly multimerized. Thus, specifically designed Env immunogens can activate naive B cells expressing human BCRs corresponding to precursors of broadly neutralizing HIV-1 antibodies even when the B cells display an autoreactive phenotype. PMID:26907590

  9. Artificial Extracellular Matrices with Oversulfated Glycosaminoglycan Derivatives Promote the Differentiation of Osteoblast-Precursor Cells and Premature Osteoblasts

    Directory of Open Access Journals (Sweden)

    Ute Hempel

    2014-01-01

    Full Text Available Sulfated glycosaminoglycans (GAG are components of the bone marrow stem cell niche and to a minor extent of mature bone tissue with important functions in regulating stem cell lineage commitment and differentiation. We anticipated that artificial extracellular matrices (aECM composed of collagen I and synthetically oversulfated GAG derivatives affect preferentially the differentiation of osteoblast-precursor cells and early osteoblasts. A set of gradually sulfated chondroitin sulfate and hyaluronan derivatives was used for the preparation of aECM. All these matrices were analysed with human bone marrow stromal cells to identify the most potent aECM and to determine the influence of the degree and position of sulfate groups and the kind of disaccharide units on the osteogenic differentiation. Oversulfated GAG derivatives with a sulfate group at the C-6 position of the N-acetylglycosamine revealed the most pronounced proosteogenic effect as determined by tissue nonspecific alkaline phosphatase activity and calcium deposition. A subset of the aECM was further analysed with different primary osteoblasts and cell lines reflecting different maturation stages to test whether the effect of sulfated GAG derivatives depends on the maturation status of the cells. It was shown that the proosteogenic effect of aECM was most prominent in early osteoblasts.

  10. Artificial Extracellular Matrices with Oversulfated Glycosaminoglycan Derivatives Promote the Differentiation of Osteoblast-Precursor Cells and Premature Osteoblasts

    Science.gov (United States)

    Hempel, Ute; Preissler, Carolin; Möller, Stephanie; Becher, Jana; Rauner, Martina; Hofbauer, Lorenz C.; Dieter, Peter

    2014-01-01

    Sulfated glycosaminoglycans (GAG) are components of the bone marrow stem cell niche and to a minor extent of mature bone tissue with important functions in regulating stem cell lineage commitment and differentiation. We anticipated that artificial extracellular matrices (aECM) composed of collagen I and synthetically oversulfated GAG derivatives affect preferentially the differentiation of osteoblast-precursor cells and early osteoblasts. A set of gradually sulfated chondroitin sulfate and hyaluronan derivatives was used for the preparation of aECM. All these matrices were analysed with human bone marrow stromal cells to identify the most potent aECM and to determine the influence of the degree and position of sulfate groups and the kind of disaccharide units on the osteogenic differentiation. Oversulfated GAG derivatives with a sulfate group at the C-6 position of the N-acetylglycosamine revealed the most pronounced proosteogenic effect as determined by tissue nonspecific alkaline phosphatase activity and calcium deposition. A subset of the aECM was further analysed with different primary osteoblasts and cell lines reflecting different maturation stages to test whether the effect of sulfated GAG derivatives depends on the maturation status of the cells. It was shown that the proosteogenic effect of aECM was most prominent in early osteoblasts. PMID:24864267

  11. Naturally death-resistant precursor cells revealed as the origin of retinoblastoma

    DEFF Research Database (Denmark)

    Trinh, Emmanuelle; Lazzerini Denchi, Eros; Helin, Kristian

    2004-01-01

    The molecular mechanisms and the cell-of-origin leading to retinoblastoma are not well defined. In this issue of Cancer Cell, Bremner and colleagues describe the first inheritable model of retinoblastoma, revealing that loss of the pocket proteins pRb and p107 deregulates cell cycle exit in retinal...

  12. Biosynthesis of the precursor of a soluble human insulin receptor ectodomain in insect Sf9 cells infected with a recombinant baculovirus.

    Science.gov (United States)

    Sissom, J F; Ellis, L

    1991-06-14

    In contrast to transfected mammalian cells, insect Sf9 cells infected with a recombinant Baculovirus inefficiently process and secrete a soluble derivative of the extracellular domain of the human insulin receptor. The high-mannose form of the receptor precursor that accumulates intracellularly is not grossly aberrant or malfolded, as its interaction with a diverse panel of monoclonal antibodies are comparable to secreted precursor and proteolytically processed receptor, both of which bear partially trimmed oligosaccharide chains. Thus the inefficient step in the biosynthesis of this protein in Sf9 cells is either at, or just preceding, the trimming of its high-mannose oligosaccharide chains.

  13. Changes in benign cell populations in cases of cervical cancer and its precursors.

    Science.gov (United States)

    Burger, G; Jutting, U; Rodenacker, K

    1981-12-01

    In two totally independent experiments, typical intermediate cells were visually selected by experienced cytotechnicians trained in the analysis of monodisperse Papanicolaou-stained ectocervical smears. The smears were carefully diagnosed per se and in correlation with routine smears from the same patients. For specimens of classes exhibiting tumor cells, the diagnosis was histologically verified. About 20 cells per specimen were selected from at least ten specimens per Papanicolaou class, amounting to total sample sizes of about 1,000 cells. In the first experiment, only cell nuclei were SMP scanned; in the second experiment, the whole cells were TV scanned. Correlation and classification analyses were performed; these resulted in the clear demonstration that intermediate cell populations in ectocervical smears are different in patients with different neoplastic gradings.

  14. Efficient differentiation of embryonic stem cells into mesodermal precursors by BMP, retinoic acid and Notch signalling.

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    Josema Torres

    Full Text Available The ability to direct differentiation of mouse embryonic stem (ES cells into specific lineages not only provides new insights into the pathways that regulate lineage selection but also has translational applications, for example in drug discovery. We set out to develop a method of differentiating ES cells into mesodermal cells at high efficiency without first having to induce embryoid body formation. ES cells were plated on a feeder layer of PA6 cells, which have membrane-associated stromal-derived inducing activity (SDIA, the molecular basis of which is currently unknown. Stimulation of ES/PA6 co-cultures with Bone Morphogenetic Protein 4 (BMP4 both favoured self-renewal of ES cells and induced differentiation into a Desmin and Nestin double positive cell population. Combined stimulation with BMP4 and all-trans Retinoic Acid (RA inhibited self-renewal and resulted in 90% of cells expressing Desmin and Nestin. Quantitative reverse transcription-polymerase chain reaction (qPCR analysis confirmed that the cells were of mesodermal origin and expressed markers of mesenchymal and smooth muscle cells. BMP4 activation of a MAD-homolog (Smad-dependent reporter in undifferentiated ES cells was attenuated by co-stimulation with RA and co-culture with PA6 cells. The Notch ligand Jag1 was expressed in PA6 cells and inhibition of Notch signalling blocked the differentiation inducing activity of PA6 cells. Our data suggest that mesodermal differentiation is regulated by the level of Smad activity as a result of inputs from BMP4, RA and the Notch pathway.

  15. Template based precursor route for the synthesis of CuInSe2 nanorod arrays for potential solar cell applications

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    Mikhail Pashchanka

    2013-12-01

    Full Text Available Polycrystalline CuInSe2 (CISe nanorods are promising for the fabrication of highly efficient active layers in solar cells. In this work we report on a nanocasting approach, which uses track-etched polycarbonate films as hard templates for obtaining three-dimensionally (3D arranged CISe nanorod arrays. Copper and indium ketoacidoximato complexes and selenourea were employed as molecular precursors. Arrays of parallel isolated cylindrical pores of 100 nm nominal diameter and 5 μm length were used for the infiltration of the precursor solution under inert atmosphere, followed by drying, thermal conversion into a preceramic ‘green body’, a subsequent dissolution of the template, and a final thermal treatment at 450 °C. The nanorods that where synthesised in this way have dimensions equal to the pore sizes of the template. Investigation of the CuInSe2 nanorod samples by spectroscopic and diffraction methods confirmed a high purity and crystallinity, and a stoichiometric composition of the CISe ternary semiconductor compound.

  16. Accelerated programmed cell death (apoptosis) in erythroid precursors of patients with severe beta-thalassemia (Cooley's anemia)

    Science.gov (United States)

    Yuan, J; Angelucci, E; Lucarelli, G; Aljurf, M; Snyder, L M; Kiefer, C R; Ma, L; Schrier, S L

    1993-07-15

    The profound and life-threatening anemia in patients with Cooley's anemia is ascribed primarily to intramedullary hemolysis (ineffective erythropoiesis), the cause of which is obscure. Based on prior morphologic data showing nuclear abnormalities, we hypothesized that accelerated apoptosis could occur in these erythroid precursors. The highly successful bone marrow (BM) transplantation program for patients with Cooley's anemia provided us with a unique opportunity to test this hypothesis. We obtained pretransplantation BM aspiration samples from patients undergoing BM transplantation in Pesaro, Italy and from their allogeneic donors. The erythroid precursors were isolated using ficoll sedimentation and then panning selecting fro CD45- cells. Cytospin and Giemsa staining showed that the separation provided greater than 90% erythroblasts. Five million of these erythroblasts were lysed and their DNA was isolated. There were obvious ladder patterns of DNA breakdown products in beta-thalassemia major samples, with less occurring in beta-thalassemia trait. Normal individuals showed only a slight smear of breakdown of DNA. These results indicate there is enhanced apoptosis in the erythroblasts in the BMs of Cooley's anemia patients. This finding might partially explain why most of these erythroblasts never survive to become mature erythrocytes.

  17. Defined and Scalable Differentiation of Human Oligodendrocyte Precursors from Pluripotent Stem Cells in a 3D Culture System

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    Gonçalo M.C. Rodrigues

    2017-06-01

    Full Text Available Oligodendrocyte precursor cells (OPCs offer considerable potential for the treatment of demyelinating diseases and injuries of the CNS. However, generating large quantities of high-quality OPCs remains a substantial challenge that impedes their therapeutic application. Here, we show that OPCs can be generated from human pluripotent stem cells (hPSCs in a three-dimensional (3D, scalable, and fully defined thermoresponsive biomaterial system. We used CRISPR/Cas9 to create a NKX2.2-EGFP human embryonic stem cell reporter line that enabled fine-tuning of early OPC specification and identification of conditions that markedly increased the number of OLIG2+ and NKX2.2+ cells generated from hPSCs. Transplantation of 50-day-old OPCs into the brains of NOD/SCID mice revealed that progenitors generated in 3D without cell selection or purification subsequently engrafted, migrated, and matured into myelinating oligodendrocytes in vivo. These results demonstrate the potential of harnessing lineage reporter lines to develop 3D platforms for rapid and large-scale production of OPCs.

  18. Ezh2 Controls an Early Hematopoietic Program and Growth and Survival Signaling in Early T Cell Precursor Acute Lymphoblastic Leukemia

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    Etienne Danis

    2016-03-01

    Full Text Available Early T cell precursor acute lymphoblastic leukemia (ETP-ALL is an aggressive subtype of ALL distinguished by stem-cell-associated and myeloid transcriptional programs. Inactivating alterations of Polycomb repressive complex 2 components are frequent in human ETP-ALL, but their functional role is largely undefined. We have studied the involvement of Ezh2 in a murine model of NRASQ61K-driven leukemia that recapitulates phenotypic and transcriptional features of ETP-ALL. Homozygous inactivation of Ezh2 cooperated with oncogenic NRASQ61K to accelerate leukemia onset. Inactivation of Ezh2 accentuated expression of genes highly expressed in human ETP-ALL and in normal murine early thymic progenitors. Moreover, we found that Ezh2 contributes to the silencing of stem-cell- and early-progenitor-cell-associated genes. Loss of Ezh2 also resulted in increased activation of STAT3 by tyrosine 705 phosphorylation. Our data mechanistically link Ezh2 inactivation to stem-cell-associated transcriptional programs and increased growth/survival signaling, features that convey an adverse prognosis in patients.

  19. Enhanced Expansion and Sustained Inductive Function of Skin‐Derived Precursor Cells in Computer‐Controlled Stirred Suspension Bioreactors

    Science.gov (United States)

    Agabalyan, Natacha A.; Borys, Breanna S.; Sparks, Holly D.; Boon, Kathryn; Raharjo, Eko W.; Abbasi, Sepideh; Kallos, Michael S.

    2016-01-01

    Abstract Endogenous dermal stem cells (DSCs) reside in the adult hair follicle mesenchyme and can be isolated and grown in vitro as self‐renewing colonies called skin‐derived precursors (SKPs). Following transplantation into skin, SKPs can generate new dermis and reconstitute the dermal papilla and connective tissue sheath, suggesting they could have important therapeutic value for the treatment of skin disease (alopecia) or injury. Controlled cell culture processes must be developed to efficiently and safely generate sufficient stem cell numbers for clinical use. Compared with static culture, stirred‐suspension bioreactors generated fivefold greater expansion of viable SKPs. SKPs from each condition were able to repopulate the dermal stem cell niche within established hair follicles. Both conditions were also capable of inducing de novo hair follicle formation and exhibited bipotency, reconstituting the dermal papilla and connective tissue sheath, although the efficiency was significantly reduced in bioreactor‐expanded SKPs compared with static conditions. We conclude that automated bioreactor processing could be used to efficiently generate large numbers of autologous DSCs while maintaining their inherent regenerative function. Stem Cells Translational Medicine 2017;6:434–443 PMID:28191777

  20. Adult skin-derived precursor Schwann cell grafts form growths in the injured spinal cord of Fischer rats.

    Science.gov (United States)

    May, Zacnicte; Kumar, Ranjan; Führmann, Tobias; Tam, Roger; Vulic, Katarina; Forero, Juan; Lucas-Osma, Ana M; Fenrich, Keith; Assinck, Peggy; Lee, Michael J; Moulson, Aaron; Shoichet, Molly S; Tetzlaff, Wolfram; Biernaskie, Jeff; Fouad, Karim

    2017-10-25

    In this study, GFP+ skin-derived precursor Schwann cells (SKP-SCs) from adult rats were grafted into the injured spinal cord of immunosuppressed rats. Our goal was to improve grafted cell survival in the injured spinal cord, which is typically low. Cells were grafted in hyaluronan-methylcellulose hydrogel (HAMC) or hyaluronan-methylcellulose modified with laminin- and fibronectin-derived peptide sequences (eHAMC). The criteria for selection of hyaluronan was for its shear-thinning properties, making the hydrogel easy to inject, methylcellulose for its inverse thermal gelation, helping to keep grafted cells in situ, and fibronectin and laminin to improve cell attachment and, thus, prevent cell death due to dissociation from substrate molecules (i.e., anoikis). Post-mortem examination revealed large masses of GFP+ SKP-SCs in the spinal cords of rats that received cells in HAMC (5 out of n = 8) and eHAMC (6 out of n = 8). Cell transplantation in eHAMC caused significantly greater spinal lesions compared to lesion and eHAMC only control groups. A parallel study showed similar masses in the contused spinal cord of rats after transplantation of adult GFP+ SKP-SCs without a hydrogel or immunosuppression. These findings suggest that adult GFP+ SKP-SCs, cultured/transplanted under the conditions described here, have a capacity for uncontrolled proliferation. Growth-formation in pre-clinical research has also been documented after transplantation of: human induced pluripotent stem cell-derived neural stem cells (Itakura et al., 2015), embryonic stem cells and embryonic stem cell-derived neurons (Brederlau et al., 2006; Dressel et al., 2008), bone marrow derived mesenchymal stem cells (Jeong et al., 2011) and rat nerve-derived SCs following in vitro expansion for ˃11 passages (Funk et al., 2007; Langford et al., 1988; Morrissey et al., 1991). It is of upmost importance to define the precise culture/transplantation parameters for maintenance of normal cell function and safe

  1. Differentiation of neurons from neural precursors generated in floating spheres from embryonic stem cells

    Directory of Open Access Journals (Sweden)

    Forrester Jeff

    2009-09-01

    Full Text Available Abstract Background Neural differentiation of embryonic stem (ES cells is usually achieved by induction of ectoderm in embryoid bodies followed by the enrichment of neuronal progenitors using a variety of factors. Obtaining reproducible percentages of neural cells is difficult and the methods are time consuming. Results Neural progenitors were produced from murine ES cells by a combination of nonadherent conditions and serum starvation. Conversion to neural progenitors was accompanied by downregulation of Oct4 and NANOG and increased expression of nestin. ES cells containing a GFP gene under the control of the Sox1 regulatory regions became fluorescent upon differentiation to neural progenitors, and ES cells with a tau-GFP fusion protein became fluorescent upon further differentiation to neurons. Neurons produced from these cells upregulated mature neuronal markers, or differentiated to glial and oligodendrocyte fates. The neurons gave rise to action potentials that could be recorded after application of fixed currents. Conclusion Neural progenitors were produced from murine ES cells by a novel method that induced neuroectoderm cells by a combination of nonadherent conditions and serum starvation, in contrast to the embryoid body method in which neuroectoderm cells must be selected after formation of all three germ layers.

  2. IL-7 and IL-15 instruct the generation of human memory stem T cells from naive precursors.

    Science.gov (United States)

    Cieri, Nicoletta; Camisa, Barbara; Cocchiarella, Fabienne; Forcato, Mattia; Oliveira, Giacomo; Provasi, Elena; Bondanza, Attilio; Bordignon, Claudio; Peccatori, Jacopo; Ciceri, Fabio; Lupo-Stanghellini, Maria Teresa; Mavilio, Fulvio; Mondino, Anna; Bicciato, Silvio; Recchia, Alessandra; Bonini, Chiara

    2013-01-24

    Long-living memory stem T cells (T(SCM)) with the ability to self-renew and the plasticity to differentiate into potent effectors could be valuable weapons in adoptive T-cell therapy against cancer. Nonetheless, procedures to specifically target this T-cell population remain elusive. Here, we show that it is possible to differentiate in vitro, expand, and gene modify in clinically compliant conditions CD8(+) T(SCM) lymphocytes starting from naive precursors. Requirements for the generation of this T-cell subset, described as CD62L(+)CCR7(+)CD45RA(+)CD45R0(+)IL-7Rα(+)CD95(+), are CD3/CD28 engagement and culture with IL-7 and IL-15. Accordingly, T(SCM) accumulates early after hematopoietic stem cell transplantation. The gene expression signature and functional phenotype define this population as a distinct memory T-lymphocyte subset, intermediate between naive and central memory cells. When transplanted in immunodeficient mice, gene-modified naive-derived T(SCM) prove superior to other memory lymphocytes for the ability to expand and differentiate into effectors able to mediate a potent xenogeneic GVHD. Furthermore, gene-modified T(SCM) are the only T-cell subset able to expand and mediate GVHD on serial transplantation, suggesting self-renewal capacity in a clinically relevant setting. These findings provide novel insights into the origin and requirements for T(SCM) generation and pave the way for their clinical rapid exploitation in adoptive cell therapy.

  3. Lithium promotes neural precursor cell proliferation: evidence for the involvement of the non-canonical GSK-3β-NF-AT signaling

    Directory of Open Access Journals (Sweden)

    Qu Zhaoxia

    2011-05-01

    Full Text Available Abstract Lithium, a drug that has long been used to treat bipolar disorder and some other human pathogenesis, has recently been shown to stimulate neural precursor growth. However, the involved mechanism is not clear. Here, we show that lithium induces proliferation but not survival of neural precursor cells. Mechanistic studies suggest that the effect of lithium mainly involved activation of the transcription factor NF-AT and specific induction of a subset of proliferation-related genes. While NF-AT inactivation by specific inhibition of its upstream activator calcineurin antagonized the effect of lithium on the proliferation of neural precursor cells, specific inhibition of the NF-AT inhibitor GSK-3β, similar to lithium treatment, promoted neural precursor cell proliferation. One important function of lithium appeared to increase inhibitory phosphorylation of GSK-3β, leading to GSK-3β suppression and subsequent NF-AT activation. Moreover, lithium-induced proliferation of neural precursor cells was independent of its role in inositol depletion. These findings not only provide mechanistic insights into the clinical effects of lithium, but also suggest an alternative therapeutic strategy for bipolar disorder and other neural diseases by targeting the non-canonical GSK-3β-NF-AT signaling.

  4. Differentiation of retinal ganglion cells and photoreceptor precursors from mouse induced pluripotent stem cells carrying an Atoh7/Math5 lineage reporter.

    Directory of Open Access Journals (Sweden)

    Bin-Bin Xie

    Full Text Available The neural retina is a critical component of the visual system, which provides the majority of sensory input in humans. Various retinal degenerative diseases can result in the permanent loss of retinal neurons, especially the light-sensing photoreceptors and the centrally projecting retinal ganglion cells (RGCs. The replenishment of lost RGCs and the repair of optic nerve damage are particularly challenging, as both RGC specification and their subsequent axonal growth and projection involve complex and precise regulation. To explore the developmental potential of pluripotent stem cell-derived neural progenitors, we have established mouse iPS cells that allow cell lineage tracing of progenitors that have expressed Atoh7/Math5, a bHLH transcription factor required for RGC production. These Atoh7 lineage reporter iPS cells encode Cre to replace one copy of the endogenous Atoh7 gene and a Cre-dependent YFP reporter in the ROSA locus. In addition, they express pluripotent markers and are capable of generating teratomas in vivo. Under anterior neural induction and neurogenic conditions in vitro, the Atoh7-Cre/ROSA-YFP iPS cells differentiate into neurons that co-express various RGC markers and YFP, indicating that these neurons are derived from Atoh7-expressing progenitors. Consistent with previous in vivo cell lineage studies, the Atoh7-Cre/ROSA-YFP iPS cells also give rise to a subset of Crx-positive photoreceptor precursors. Furthermore, inhibition of Notch signaling in the iPSC cultures results in a significant increase of YFP-positive RGCs and photoreceptor precursors. Together, these results show that Atoh7-Cre/ROSA-YFP iPS cells can be used to monitor the development and survival of RGCs and photoreceptors from pluripotent stem cells.

  5. Quantitative distinction of the morphological characteristic of erythrocyte precursor cells with texture analysis using gray level co-occurrence matrix.

    Science.gov (United States)

    Kono, Keigo; Hayata, Ruka; Murakami, Satoru; Yamamoto, Mai; Kuroki, Maiko; Nanato, Kana; Takahashi, Kazuto; Miwa, Keiko; Tsutsumi, Yutaka; Okada, Kazunori; Kaga, Sanae; Mikami, Taisei; Masauzi, Nobuo

    2017-02-21

    Morphological characteristics of blood cells are still qualitatively defined. So a texture analysis (Tx) method using gray level co-occurrence matrices (GLCMs; CM-Tx method) was applied to images of erythrocyte precursor cells (EPCs) for quantitatively distinguishing four types of EPC stages: proerythroblast, basophilic erythroblast, polychromatic erythroblast, and orthochromatic erythroblast. Fifty-five images of four types of EPCs were downloaded from an atlas uploaded by the Blood Cell Morphology Standardization Subcommittee (BCMSS) of the Japanese Society of Laboratory Hematology (JSLH). Using in-house programs, two types of GLCMs-(R: d=1, θ=0°) and (U: d=1, θ=270°)-and nine types of texture distinction index (TDI) were calculated with images removed outer part of cell. Three binary decision trees were sequentially divided among four types of EPC with the sum average of GLCM (U), the contrast of GLCM (R), and the sum average of GLCM (U). The average concordance rate (sensitivity) of CM-Tx method with the judgments of eleven experts in the BCMSS of the JSLH was 95.8% (87.5-100.0), and the average specificity was 97.6% (92.5-100.0). The CM-Tx method is an effective tool for quantitative distinction of EPC with their morphological features. © 2017 Wiley Periodicals, Inc.

  6. Clonal human fetal ventral mesencephalic dopaminergic neuron precursors for cell therapy research.

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    Tania Ramos-Moreno

    Full Text Available A major challenge for further development of drug screening procedures, cell replacement therapies and developmental studies is the identification of expandable human stem cells able to generate the cell types needed. We have previously reported the generation of an immortalized polyclonal neural stem cell (NSC line derived from the human fetal ventral mesencephalon (hVM1. This line has been biochemically, genetically, immunocytochemically and electrophysiologically characterized to document its usefulness as a model system for the generation of A9 dopaminergic neurons (DAn. Long-term in vivo transplantation studies in parkinsonian rats showed that the grafts do not mature evenly. We reasoned that diverse clones in the hVM1 line might have different abilities to differentiate. In the present study, we have analyzed 9 hVM1 clones selected on the basis of their TH generation potential and, based on the number of v-myc copies, v-myc down-regulation after in vitro differentiation, in vivo cell cycle exit, TH⁺ neuron generation and expression of a neuronal mature marker (hNSE, we selected two clones for further in vivo PD cell replacement studies. The conclusion is that homogeneity and clonality of characterized NSCs allow transplantation of cells with controlled properties, which should help in the design of long-term in vivo experiments.

  7. Programming Pluripotent Precursor Cells Derived from Xenopus Embryos to Generate Specific Tissues and Organs

    Directory of Open Access Journals (Sweden)

    Annette Borchers

    2010-11-01

    Full Text Available Xenopus embryos provide a rich source of pluripotent cells that can be differentiated into functional organs. Since the molecular principles of vertebrate organogenesis appear to be conserved between Xenopus and mammals, this system can provide useful guidelines for the directional manipulation of human embryonic stem cells. Pluripotent Xenopus cells can be easily isolated from the animal pole of blastula stage Xenopus embryos. These so called “animal cap” cells represent prospective ectodermal cells, but give rise to endodermal, mesodermal and neuro-ectodermal derivatives if treated with the appropriate factors. These factors include evolutionary conserved modulators of the key developmental signal transduction pathways that can be supplied either by mRNA microinjection or direct application of recombinant proteins. This relatively simple system has added to our understanding of pancreas, liver, kidney, eye and heart development. In particular, recent studies have used animal cap cells to generate ectopic eyes and hearts, setting the stage for future work aimed at programming pluripotent cells for regenerative medicine.

  8. Sulfurization of sputtered Ag–In precursors for AgInS{sub 2} solar cell absorber layers

    Energy Technology Data Exchange (ETDEWEB)

    Anantha Sunil, M. [Energy and Health Monitoring Instrumentation Laboratory, Department of Instrumentation & Applied Physics, Indian Institute of Science, Bangalore 560012 (India); Thota, Narayana [Advanced Materials Research Laboratory, Department of Physics, Yogi Vemana University, Kadapa 516003 (India); Deepa, K.G. [Energy and Health Monitoring Instrumentation Laboratory, Department of Instrumentation & Applied Physics, Indian Institute of Science, Bangalore 560012 (India); Jampana, Nagaraju, E-mail: solarjnr@gmail.com [Energy and Health Monitoring Instrumentation Laboratory, Department of Instrumentation & Applied Physics, Indian Institute of Science, Bangalore 560012 (India)

    2015-11-30

    Silver indium sulfide (AgInS{sub 2}) thin films are deposited by sequential sputtering of metallic precursor [Ag/In] followed by sulfurization. Effect of substrate temperature (T{sub sub}) during sulfurization process on the film growth is studied by varying the substrate temperature from 350 to 500 °C. Films prepared above 350 °C showed a mixture of orthorhombic and tetragonal phases of AgInS{sub 2} with tetragonal phase being dominant. Better crystalline, nearly stoichiometric and p-type films are obtained at a substrate temperature of 500 °C. The characteristic A{sub 1} mode of AgInS{sub 2} chalcopyrite structure is observed in the Raman spectra at 274 cm{sup −1} for the films prepared above 350 °C. The grain size of the film increases from 489 to 895 nm with the increase in substrate temperature. The binding energies of the constituent elements are determined using XPS. The band gap of AgInS{sub 2} films is in the range of 1.64–1.92 eV and the absorption coefficient is found to be > 10{sup 4} cm{sup −1}. Preliminary studies on the AgInS{sub 2}/ZnS solar cell showed an efficiency of 0.3%. - Highlights: • AgInS{sub 2} films are grown by sulfurization of sputtered metal precursors. • Effect of substrate temperature on the growth of AgInS{sub 2} films is studied. • Films sulfurized at 500 °C have the best structural and opto-electrical properties. • AgInS{sub 2}/ZnS solar cell has been fabricated with an efficiency of ~ 0.3%.

  9. Manoyl oxide (13R), the biosynthetic precursor of forskolin, is synthesized in specialized root cork cells in Coleus forskohlii.

    Science.gov (United States)

    Pateraki, Irini; Andersen-Ranberg, Johan; Hamberger, Britta; Heskes, Allison Maree; Martens, Helle Juel; Zerbe, Philipp; Bach, Søren Spanner; Møller, Birger Lindberg; Bohlmann, Jörg; Hamberger, Björn

    2014-03-01

    Forskolin, a complex labdane diterpenoid found in the root of Coleus forskohlii (Lamiaceae), has received attention for its broad range of pharmacological activities, yet the biosynthesis has not been elucidated. We detected forskolin in the root cork of C. forskohlii in a specialized cell type containing characteristic structures with histochemical properties consistent with oil bodies. Organelle purification and chemical analysis confirmed the localization of forskolin and of its simplest diterpene precursor backbone, (13R) manoyl oxide, to the oil bodies. The labdane diterpene backbone is typically synthesized by two successive reactions catalyzed by two distinct classes of diterpene synthases. We have recently described the identification of a small gene family of diterpene synthase candidates (CfTPSs) in C. forskohlii. Here, we report the functional characterization of four CfTPSs using in vitro and in planta assays. CfTPS2, which synthesizes the intermediate copal-8-ol diphosphate, in combination with CfTPS3 resulted in the stereospecific formation of (13R) manoyl oxide, while the combination of CfTPS1 and CfTPS3 or CfTPS4 led to formation of miltiradiene, precursor of abietane diterpenoids in C. forskohlii. Expression profiling and phylogenetic analysis of the CfTPS family further support the functional diversification and distinct roles of the individual diterpene synthases and the involvement of CfTPS1 to CfTPS4 in specialized metabolism and of CfTPS14 and CfTPS15 in general metabolism. Our findings pave the way toward the discovery of the remaining components of the pathway to forskolin, likely localized in this specialized cell type, and support a role of oil bodies as storage organelles for lipophilic bioactive metabolites.

  10. Endothelial Cells as Precursors for Osteoblasts in the Metastatic Prostate Cancer Bone

    Directory of Open Access Journals (Sweden)

    Ana E. Paiva

    2017-11-01

    Full Text Available Prostate cancer cells metastasize to the bones, causing ectopic bone formation, which results in fractures and pain. The cellular mechanisms underlying new bone production are unknown. In a recent study, Lin and colleagues, by using state-of-the-art techniques, including prostate cancer mouse models in combination with sophisticated in vivo lineage-tracing technologies, revealed that endothelial cells form osteoblasts induced by prostate cancer metastasis in the bone. Strikingly, genetic deletion of osteorix protein from endothelial cells affected prostate cancer–induced osteogenesis in vivo. Deciphering the osteoblasts origin in the bone microenvironment may result in the development of promising new molecular targets for prostate cancer therapy.

  11. Co-transplantation of syngeneic mesenchymal stem cells improves survival of allogeneic glial-restricted precursors in mouse brain.

    Science.gov (United States)

    Srivastava, Amit K; Bulte, Camille A; Shats, Irina; Walczak, Piotr; Bulte, Jeff W M

    2016-01-01

    Loss of functional cells from immunorejection during the early post-transplantation period is an important factor that reduces the efficacy of stem cell-based therapies. Recent studies have shown that transplanted mesenchymal stem cells (MSCs) can exert therapeutic effects by secreting anti-inflammatory and pro-survival trophic factors. We investigated whether co-transplantation of MSCs could improve the survival of other transplanted therapeutic cells. Allogeneic glial-restricted precursors (GRPs) were isolated from the brain of a firefly luciferase transgenic FVB mouse (at E13.5 stage) and intracerebrally transplanted, either alone, or together with syngeneic MSCs in immunocompetent BALB/c mice (n=20) or immunodeficient Rag2(-/-) mice as survival control (n=8). No immunosuppressive drug was given to any animal. Using bioluminescence imaging (BLI) as a non-invasive readout of cell survival, we found that co-transplantation of MSCs significantly improved (ptransplanted cells surviving in both the GRP only and the GRP+MSC group. In contrast, on day 21 post-transplantation, we observed a 94.2% decrease in BLI signal intensity in immunocompetent mice transplanted with GRPs alone versus 68.1% in immunocompetent mice co-transplanted with MSCs and GRPs (pcells, reduced astrogliosis, and a higher number of FoxP3(+) cells at the site of transplantation for the immunocompetent mice receiving MSCs. The present study demonstrates that co-transplantation of MSCs can be used to create a microenvironment that is more conducive to the survival of allogeneic GRPs. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. CXCR3 expression on CD34(+) hemopoietic progenitors induced by granulocyte-macrophage colony-stimulating factor

    DEFF Research Database (Denmark)

    Jinquan, T; Anting, L; Jacobi, H H

    2001-01-01

    CXCR3, known to have four ligands (IFN-gamma inducible protein 10 (gamma IP-10), monokine induced by IFN-gamma (Mig), I-TAC, and 6Ckine), is predominantly expressed on memory/activated T lymphocytes. We recently reported that GM-CSF induces CXCR3 expression on CD34(+) hemopoietic progenitors......, in which gamma IP-10 and Mig induce chemotaxis and adhesion. Here we further report that stimulation with GM-CSF causes phosphorylation of Syk protein kinase, but neither Casitas B-lineage lymphoma (Cbl) nor Cbl-b in CD34(+) hemopoietic progenitors can be blocked by anti-CD116 mAb. Specific Syk blocking...... generated by PNA antisense completely inhibits GM-CSF-induced CXCR3 expression in CD34(+) progenitors at both mRNA and protein as well as at functional levels (chemotaxis and adhesion). Cbl and Cbl-b blocking have no such effects. Thus, GM-CSF binds to its receptor CD116, and consequently activates Syk...

  13. Human iPSC Derived GABA Ergic Precursor Cell Therapy for Chronic Epilepsy

    Science.gov (United States)

    2016-10-01

    of hMGE progenitors (obtained from hPSCs expanded from human embryonic stem cells) that were transduced with DREADDs through CRISPR / Cas9 technology... CRISPR / Cas9 DREADDs). These cells were obtained from our collaborator, Dr. Su-Chun Zhang, University of Wisconsin. The second approach employed...with CRISPR / Cas9 DREADDs or mCherry DREADDs received daily subcutaneous injections of cyclosporine to prevent graft rejection. CERs assigned to CNO

  14. Phosphatidylserine functions as the major precursor of phosphatidylethanolamine in cultured BHK-21 cells.

    OpenAIRE

    Voelker, D R

    1984-01-01

    Pulse-chase experiments with [3H]serine provide evidence that significant amounts of phosphatidylserine turn over to form phosphatidylethanolamine in mammalian cells in tissue culture. Phospholipase C hydrolysis of [3H]phosphatidylethanolamine synthesized from [3H]serine by baby hamster kidney (BHK-21) cells demonstrates that nearly all of the radiolabel remains in the ethanolamine moiety. Uniform labeling experiments with [3H]serine further demonstrate that the distribution of radiolabel in ...

  15. Evidence for the formation of endothelin by lysed red blood cells from endogenous precursor.

    Science.gov (United States)

    Tippler, B; Herbst, C; Simmet, T

    1994-12-12

    The release of endothelin from various blood cell fractions was investigated. Human as well as rat blood cell fractions homogenized by sonification were incubated in buffer for up to 60 min. Neither in platelet nor leukocyte homogenates from either species could immunoreactive endothelin be detected. In contrast, homogenates of red blood cells from both species showed a rapid and time-dependent rise of immunoreactive endothelin levels, reaching a peak at 15 min and decreasing thereafter. However, at time point 0 no immunoreactive endothelin could be detected. Reverse phase high performance liquid chromatography showed immunoreactive endothelin to consist of endothelin-1 as well as big endothelin-1. The release of immunoreactive endothelin in human and rat homogenates was concentration-dependently inhibited by the protease inhibitors, leupeptin, phosphoramidon, chymostatin and pepstatin A in order of increasing potency. Intact red blood cells did not incorporate [125I]endothelin-1 nor did they transform exogenous big endothelin-1 to endothelin-1. However, haemolysis of red blood cells with hypotonic saline (0.2%) or incubation with pore-forming staphylococcal alpha-toxin induced the release of immunoreactive endothelin into the buffer samples. Thus, apart from the indirect vasoconstrictor, haemoglobin, red blood cells can also liberate the direct vasoconstrictor, endothelin, a finding expected to be of considerable pathophysiological significance.

  16. Reprogramming fibroblasts to neural-precursor-like cells by structured overexpression of pallial patterning genes.

    Science.gov (United States)

    Raciti, Marilena; Granzotto, Marilena; Duc, Minh Do; Fimiani, Cristina; Cellot, Giada; Cherubini, Enrico; Mallamaci, Antonello

    2013-11-01

    In this study, we assayed the capability of four genes implicated in embryonic specification of the cortico-cerebral field, Foxg1, Pax6, Emx2 and Lhx2, to reprogramme mouse embryonic fibroblasts towards neural identities. Lentivirus-mediated, TetON-dependent overexpression of Pax6 and Foxg1 transgenes specifically activated the neural stem cell (NSC) reporter Sox1-EGFP in a substantial fraction of engineered cells. The efficiency of this process was enhanced up to ten times by simultaneous inactivation of Trp53 and co-administration of a specific drug mix inhibiting HDACs, H3K27-HMTase and H3K4m2-demethylase. Remarkably, a fraction of the reprogrammed population expressed other NSC markers and retained its new identity, even after switching off the reprogramming transgenes. When transferred into a pro-differentiative environment, Pax6/Foxg1-overexpressing cells activated the neuronal marker Tau-EGFP. Frequency of Tau-EGFP positive cells was almost doubled upon delayed delivery of Emx2 and Lhx2 transgenes. A further improvement of the neuron-like cell output was achieved by inhibition of the BMP and TGFβ pathways. Tau-EGFP positive cells were able to generate action potentials upon injection of depolarizing current pulses, further indicating their neuron-like phenotype. © 2013.

  17. Regulatory Role of Redox Balance in Determination of Neural Precursor Cell Fate

    Directory of Open Access Journals (Sweden)

    Mohamed Ariff Iqbal

    2017-01-01

    Full Text Available In 1990s, reports of discovery of a small group of cells capable of proliferation and contribution to formation of new neurons in the central nervous system (CNS reversed a century-old concept on lack of neurogenesis in the adult mammalian brain. These cells are found in all stages of human life and contribute to normal cellular turnover of the CNS. Therefore, the identity of regulating factors that affect their proliferation and differentiation is a highly noteworthy issue for basic scientists and their clinician counterparts for therapeutic purposes. The cues for such control are embedded in developmental and environmental signaling through a highly regulated tempo-spatial expression of specific transcription factors. Novel findings indicate the importance of reactive oxygen species (ROS in the regulation of this signaling system. The elusive nature of ROS signaling in many vital processes from cell proliferation to cell death creates a complex literature in this field. Here, we discuss the emerging thoughts on the importance of redox regulation of proliferation and maintenance in mammalian neural stem and progenitor cells under physiological and pathological conditions. The current knowledge on ROS-mediated changes in redox-sensitive proteins that govern the molecular mechanisms in proliferation and differentiation of these cells is reviewed.

  18. Pulsed DC Electric Field-Induced Differentiation of Cortical Neural Precursor Cells.

    Directory of Open Access Journals (Sweden)

    Hui-Fang Chang

    Full Text Available We report the differentiation of neural stem and progenitor cells solely induced by direct current (DC pulses stimulation. Neural stem and progenitor cells in the adult mammalian brain are promising candidates for the development of therapeutic neuroregeneration strategies. The differentiation of neural stem and progenitor cells depends on various in vivo environmental factors, such as nerve growth factor and endogenous EF. In this study, we demonstrated that the morphologic and phenotypic changes of mouse neural stem and progenitor cells (mNPCs could be induced solely by exposure to square-wave DC pulses (magnitude 300 mV/mm at frequency of 100-Hz. The DC pulse stimulation was conducted for 48 h, and the morphologic changes of mNPCs were monitored continuously. The length of primary processes and the amount of branching significantly increased after stimulation by DC pulses for 48 h. After DC pulse treatment, the mNPCs differentiated into neurons, astrocytes, and oligodendrocytes simultaneously in stem cell maintenance medium. Our results suggest that simple DC pulse treatment could control the fate of NPCs. With further studies, DC pulses may be applied to manipulate NPC differentiation and may be used for the development of therapeutic strategies that employ NPCs to treat nervous system disorders.

  19. Pulsed DC Electric Field-Induced Differentiation of Cortical Neural Precursor Cells.

    Science.gov (United States)

    Chang, Hui-Fang; Lee, Ying-Shan; Tang, Tang K; Cheng, Ji-Yen

    2016-01-01

    We report the differentiation of neural stem and progenitor cells solely induced by direct current (DC) pulses stimulation. Neural stem and progenitor cells in the adult mammalian brain are promising candidates for the development of therapeutic neuroregeneration strategies. The differentiation of neural stem and progenitor cells depends on various in vivo environmental factors, such as nerve growth factor and endogenous EF. In this study, we demonstrated that the morphologic and phenotypic changes of mouse neural stem and progenitor cells (mNPCs) could be induced solely by exposure to square-wave DC pulses (magnitude 300 mV/mm at frequency of 100-Hz). The DC pulse stimulation was conducted for 48 h, and the morphologic changes of mNPCs were monitored continuously. The length of primary processes and the amount of branching significantly increased after stimulation by DC pulses for 48 h. After DC pulse treatment, the mNPCs differentiated into neurons, astrocytes, and oligodendrocytes simultaneously in stem cell maintenance medium. Our results suggest that simple DC pulse treatment could control the fate of NPCs. With further studies, DC pulses may be applied to manipulate NPC differentiation and may be used for the development of therapeutic strategies that employ NPCs to treat nervous system disorders.

  20. Vesicular glutamate transporters play a role in neuronal differentiation of cultured SVZ-derived neural precursor cells.

    Directory of Open Access Journals (Sweden)

    Eduardo H Sánchez-Mendoza

    Full Text Available The role of glutamate in the regulation of neurogenesis is well-established, but the role of vesicular glutamate transporters (VGLUTs and excitatory amino acid transporters (EAATs in controlling adult neurogenesis is unknown. Here we investigated the implication of VGLUTs in the differentiation of subventricular zone (SVZ-derived neural precursor cells (NPCs. Our results show that NPCs express VGLUT1-3 and EAAT1-3 both at the mRNA and protein level. Their expression increases during differentiation closely associated with the expression of marker genes. In expression analyses we show that VGLUT1 and VGLUT2 are preferentially expressed by cultured SVZ-derived doublecortin+ neuroblasts, while VGLUT3 is found on GFAP+ glial cells. In cultured NPCs, inhibition of VGLUT by Evans Blue increased the mRNA level of neuronal markers doublecortin, B3T and MAP2, elevated the number of NPCs expressing doublecortin protein and promoted the number of cells with morphological appearance of branched neurons, suggesting that VGLUT function prevents neuronal differentiation of NPCs. This survival- and differentiation-promoting effect of Evans blue was corroborated by increased AKT phosphorylation and reduced MAPK phosphorylation. Thus, under physiological conditions, VGLUT1-3 inhibition, and thus decreased glutamate exocytosis, may promote neuronal differentiation of NPCs.

  1. Gallium nitride induces neuronal differentiation markers in neural stem/precursor cells derived from rat cerebral cortex.

    Science.gov (United States)

    Chen, Chi-Ruei; Li, Yi-Chen; Young, Tai-Horng

    2009-09-01

    In the present study, gallium nitride (GaN) was used as a substrate to culture neural stem/precursor cells (NSPCs), isolated from embryonic rat cerebral cortex, to examine the effect of GaN on the behavior of NSPCs in the presence of basic fibroblast growth factor (bFGF) in serum-free medium. Morphological studies showed that neurospheres maintained their initial shape and formed many long and thick processes with the fasciculate feature on GaN. Immunocytochemical characterization showed that GaN could induce the differentiation of NSPCs into neurons and astrocytes. Compared to poly-d-lysine (PDL), the most common substrate used for culturing neurons, there was considerable expression of synapsin I for differentiated neurons on GaN, suggesting GaN could induce the differentiation of NSPCs towards the mature differentiated neurons. Western blot analysis showed that the suppression of glycogen synthase kinase-3beta (GSK-3beta) activity was one of the effects of GaN-promoted NSPC differentiation into neurons. Finally, compared to PDL, GaN could significantly improve cell survival to reduce cell death after long-term culture. These results suggest that GaN potentially has a combination of electric characteristics suitable for developing neuron and/or NSPC chip systems.

  2. Brown fat determination and development from muscle precursor cells by novel action of bone morphogenetic protein 6.

    Directory of Open Access Journals (Sweden)

    Ankur Sharma

    Full Text Available Brown adipose tissue (BAT plays a pivotal role in promoting energy expenditure by the virtue of uncoupling protein-1 (UCP-1 that differentiates BAT from its energy storing white adipose tissue (WAT counterpart. The clinical implication of "classical" BAT (originates from Myf5 positive myoblastic lineage or the "beige" fat (originates through trans-differentiation of WAT activation in improving metabolic parameters is now becoming apparent. However, the inducers and endogenous molecular determinants that govern the lineage commitment and differentiation of classical BAT remain obscure. We report here that in the absence of any forced gene expression, stimulation with bone morphogenetic protein 6 (BMP6 induces brown fat differentiation from skeletal muscle precursor cells of murine and human origins. Through a comprehensive transcriptional profiling approach, we have discovered that two days of BMP6 stimulation in C2C12 myoblast cells is sufficient to induce genes characteristic of brown preadipocytes. This developmental switch is modulated in part by newly identified regulators, Optineurin (Optn and Cyclooxygenase-2 (Cox2. Furthermore, pathway analyses using the Causal Reasoning Engine (CRE identified additional potential causal drivers of this BMP6 induced commitment switch. Subsequent analyses to decipher key pathway that facilitates terminal differentiation of these BMP6 primed cells identified a key role for Insulin Like Growth Factor-1 Receptor (IGF-1R. Collectively these data highlight a therapeutically innovative role for BMP6 by providing a means to enhance the amount of myogenic lineage derived brown fat.

  3. Pool sizes of precursors for phosphatidylcholine formation in adult rat lung type II cells

    NARCIS (Netherlands)

    Posta, M.; Batenburg, J.J.; Smith, B.T.; Golde, L.M.G. van

    1984-01-01

    1. 1. The pool sizes of the choline intermediates and cofactors involved in the CDPcholine pathway were studied in alveolar type II cells from adult rat lung. 2. 2. The choline phosphate pool was much larger than both the choline and CDPcholine pools. 3. 3. Kinetic analysis of the pool sizes

  4. BIOCONVERSION OF NATURALLY-OCCURRING PRECURSORS AND RELATED SYNTHETIC COMPOUNDS USING PLANT-CELL CULTURES

    NARCIS (Netherlands)

    PRAS, N

    1992-01-01

    The nearly unlimited enzymatic potential of cultured plant cells can basically be employed for bioconversion purposes. Plant enzymes are able to catalyze regio- and stereospecific reactions and can therefore be applied to the production of compounds of pharmaceutical interest. Naturally occurring as

  5. Characterization of precursor-based ZnO transport layers in inverted polymer solar cells

    NARCIS (Netherlands)

    Grossiord, N.; Bruyn, P. de; Moet, D.J.D.; Andriessen, R.; Blom, P.W.M.

    2014-01-01

    A wide range of characterization techniques are used to study spin-coated films of zinc oxide (ZnO) obtained from thermal decomposition of zinc acetylacetonate hydrate. Inverted organic solar cells with ZnO transport layers were prepared. Deposition conditions of the solution onto the substrate

  6. A vHNF1/TCF2-HNF6 cascade regulates the transcription factor network that controls generation of pancreatic precursor cells.

    Science.gov (United States)

    Poll, Aurélie V; Pierreux, Christophe E; Lokmane, Ludmilla; Haumaitre, Cécile; Achouri, Younes; Jacquemin, Patrick; Rousseau, Guy G; Cereghini, Silvia; Lemaigre, Frédéric P

    2006-01-01

    Generation of pancreatic precursor cells in the endoderm is controlled by a network of transcription factors. Hepatocyte nuclear factor-6 (HNF6) is a key player in this network, because it controls the initiation of the expression of pancreatic and duodenal homeobox 1 (Pdx1), the earliest marker of pancreatic precursor cells. To further characterize this network, we have investigated how the expression of HNF6 is controlled in mouse endoderm, by using in vitro and in vivo protein-DNA interaction techniques combined with endoderm electroporation, transgenesis, and gene inactivation in embryos. We delineated Hnf6 regulatory regions that confer expression of a reporter gene in the embryonic endoderm but not in extraembryonic visceral endoderm. HNF6 expression in the embryonic endoderm was found to depend on an intronic enhancer. This enhancer contains functional binding sites for the tissue-specific factors of the forkhead box A and HNF1 families. Among the latter, variant HNF1 (vHNF1)/TCF2, which is expressed before HNF6 in the endoderm, was found to be critical for HNF6 expression. Therefore, the sequential activation of vHNF1, HNF6, and Pdx1 in the endoderm appears to control the generation of pancreatic precursors. This cascade may be used to benchmark in vitro differentiation of pancreatic precursor cells from embryonic stem cells, for cell therapy of diabetes.

  7. BRCA1 promoter methylation of normal breast epithelial cells as a possible precursor for BRCA1-methylated breast cancer

    Science.gov (United States)

    Otani, Yoko; Miyake, Tomohiro; Kagara, Naofumi; Shimoda, Masafumi; Naoi, Yasuto; Maruyama, Naomi; Shimomura, Atsuhi; Shimazu, Kenzo; Kim, Seung Jin; Noguchi, Shinzaburo

    2014-01-01

    The breast cancer susceptibility gene 1 (BRCA1) and glutathione S-transferase P1 (GSTP1) promoters are reportedly often methylated in breast cancer tissues. Their methylation status in surrounding normal breast tissues has not been examined thoroughly although this may well be important for a better understanding of breast carcinogenesis. In this study, BRCA1 and GSTP1 promoter methylation was examined by methylation-specific PCR assay. Patients with BRCA1-methylated (n = 15) or BRCA1-unmethylated (n = 15) tumors and those with GSTP1-methylated (n = 9) or GSTP1-unmethylated (n = 11) tumors were included in the present study. Methylation status of manually micro-dissected normal epithelial cells from the formalin-fixed paraffin-embedded sections of normal breast tissues adjacent to and distant from the tumors was examined at multiple sites (n = 1–5). Of the 15 patients with BRCA1-methylated tumors, 9 harbored BRCA1 promoter methylation in at least one site of the normal breast tissues. However, no BRCA1 promoter methylation was observed at any site of the normal tissues of the 15 patients with BRCA1-unmethylated tumors. No GSTP1 promoter methylation was observed in the normal tissues regardless of the methylation status of the tumors. The presence of BRCA1 promoter methylation in the normal tissues was confirmed in the epithelial cells enriched with the magnetic-activated cell sorting method. Our findings suggest that a small proportion of normal breast epithelial cells with BRCA1 promoter methylation can be precursor cells from which BRCA1-methylated breast tumors may originate. This does not apply to GSTP1 promoter methylation. PMID:25155055

  8. Abrogation of β-catenin signaling in oligodendrocyte precursor cells reduces glial scarring and promotes axon regeneration after CNS injury.

    Science.gov (United States)

    Rodriguez, Justin P; Coulter, Michael; Miotke, Jill; Meyer, Ronald L; Takemaru, Ken-Ichi; Levine, Joel M

    2014-07-30

    When the brain or spinal cord is injured, glial cells in the damaged area undergo complex morphological and physiological changes resulting in the formation of the glial scar. This scar contains reactive astrocytes, activated microglia, macrophages and other myeloid cells, meningeal cells, proliferating oligodendrocyte precursor cells (OPCs), and a dense extracellular matrix. Whether the scar is beneficial or detrimental to recovery remains controversial. In the acute phase of recovery, scar-forming astrocytes limit the invasion of leukocytes and macrophages, but in the subacute and chronic phases of injury the glial scar is a physical and biochemical barrier to axonal regrowth. The signals that initiate the formation of the glial scar are unknown. Both canonical and noncanonical signaling Wnts are increased after spinal cord injury (SCI). Because Wnts are important regulators of OPC and oligodendrocyte development, we examined the role of canonical Wnt signaling in the glial reactions to CNS injury. In adult female mice carrying an OPC-specific conditionally deleted β-catenin gene, there is reduced proliferation of OPCs after SCI, reduced accumulation of activated microglia/macrophages, and reduced astrocyte hypertrophy. Using an infraorbital optic nerve crush injury, we show that reducing β-catenin-dependent signaling in OPCs creates an environment that is permissive to axonal regeneration. Viral-induced expression of Wnt3a in the normal adult mouse spinal cord induces an injury-like response in glia. Thus canonical Wnt signaling is both necessary and sufficient to induce injury responses among glial cells. These data suggest that targeting Wnt expression after SCI may have therapeutic potential in promoting axon regeneration. Copyright © 2014 the authors 0270-6474/14/3410285-13$15.00/0.

  9. Propofol at Clinically Relevant Concentrations Increases Neuronal Differentiation but Is Not Toxic to Hippocampal Neural Precursor Cells In Vitro

    Science.gov (United States)

    Sall, Jeffrey W.; Stratmann, Greg; Leong, Jason; Woodward, Elliott; Bickler, Philip E.

    2012-01-01

    Background Propofol in the early postnatal period has been shown to cause brain cell death. One proposed mechanism for cognitive dysfunction after anesthesia is alteration of neural stem cell function and neurogenesis. We examined the effect of propofol on neural precursor or stem cells (NPCs) grown in vitro. Methods Hippocampal derived NPCs from postnatal day 2 rats were exposed to propofol or to Diprivan. NPCs were then analyzed for bromodeoxyuridine incorporation to measure proliferation. Cell death was measured by lactate dehydrogenase release. Immunocytochemistry was used to evaluate the expression of neuronal and glial markers in differentiating NPCs exposed to propofol. Results Propofol dose dependently increases the release of lactate dehydrogenase from NPCs under both proliferating and differentiating conditions at supraclinical concentrations (> 7.1μM). Both Diprivan and propofol had the same effect on NPCs. Propofol mediated release of lactate dehydrogenase is not inhibited by blocking the γ-aminobutyric acid type A receptor or extracellular calcium influx and is not mediated by caspase-3/7. Direct γ-aminobutyric acid type A receptor activation did not have the same effect. In differentiating NPCs 6 h of propofol at 2.1 μM increased the number neurons but not glial cells 4 days later. Increased neuronal differentiation was not blocked by Bicuculline. Conclusions Only supraclinical concentrations of propofol or Diprivan kill NPCs in culture by a non-γ-aminobutyric acid type A, noncaspase 3 mechanism. Clinically relevant doses of propofol increase neuronal fate choice by a non-γ-aminobutyric acid type A mechanism. PMID:23001052

  10. Model Hirano bodies protect against tau-independent and tau-dependent cell death initiated by the amyloid precursor protein intracellular domain.

    Directory of Open Access Journals (Sweden)

    Matthew Furgerson

    Full Text Available The main pathological hallmarks of Alzheimer's disease are amyloid-beta plaques and neurofibrillary tangles, which are primarily composed of amyloid precursor protein (APP and tau, respectively. These proteins and their role in the mechanism of neurodegeneration have been extensively studied. Hirano bodies are a frequently occurring pathology in Alzheimer's disease as well as other neurodegenerative diseases. However, the physiological role of Hirano bodies in neurodegenerative diseases has yet to be determined. We have established cell culture models to study the role of Hirano bodies in amyloid precursor protein and tau-induced cell death mechanisms. Exogenous expression of APP and either of its c-terminal fragments c31 or Amyloid Precursor Protein Intracellular Domain c58 (AICDc58 enhance cell death. The presence of tau is not required for this enhanced cell death. However, the addition of a hyperphosphorylated tau mimic 352PHPtau significantly increases cell death in the presence of both APP and c31 or AICDc58 alone. The mechanism of cell death induced by APP and its c-terminal fragments and tau was investigated. Fe65, Tip60, p53, and caspases play a role in tau-independent and tau-dependent cell death. In addition, apoptosis was determined to contribute to cell death. The presence of model Hirano bodies protected against cell death, indicating Hirano bodies may play a protective role in neurodegeneration.

  11. Model Hirano bodies protect against tau-independent and tau-dependent cell death initiated by the amyloid precursor protein intracellular domain.

    Science.gov (United States)

    Furgerson, Matthew; Fechheimer, Marcus; Furukawa, Ruth

    2012-01-01

    The main pathological hallmarks of Alzheimer's disease are amyloid-beta plaques and neurofibrillary tangles, which are primarily composed of amyloid precursor protein (APP) and tau, respectively. These proteins and their role in the mechanism of neurodegeneration have been extensively studied. Hirano bodies are a frequently occurring pathology in Alzheimer's disease as well as other neurodegenerative diseases. However, the physiological role of Hirano bodies in neurodegenerative diseases has yet to be determined. We have established cell culture models to study the role of Hirano bodies in amyloid precursor protein and tau-induced cell death mechanisms. Exogenous expression of APP and either of its c-terminal fragments c31 or Amyloid Precursor Protein Intracellular Domain c58 (AICDc58) enhance cell death. The presence of tau is not required for this enhanced cell death. However, the addition of a hyperphosphorylated tau mimic 352PHPtau significantly increases cell death in the presence of both APP and c31 or AICDc58 alone. The mechanism of cell death induced by APP and its c-terminal fragments and tau was investigated. Fe65, Tip60, p53, and caspases play a role in tau-independent and tau-dependent cell death. In addition, apoptosis was determined to contribute to cell death. The presence of model Hirano bodies protected against cell death, indicating Hirano bodies may play a protective role in neurodegeneration.

  12. Preparation of CuIn(S,Se){sub 2} films by PLD of precursor layers and post-annealing and their application to solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Kawabe, Toshiyuki; Maeda, Tsuyoshi; Wada, Takahiro [Department of Materials Chemistry, Ryukoku University, Seta, Otsu (Japan)

    2017-06-15

    Cu-In-S precursor films were deposited at various substrate temperatures by pulsed laser deposition (PLD). CuIn(S,Se){sub 2} films were prepared by post-annealing the Cu-In-S precursor films in H{sub 2}S and Se atmosphere. CuIn(S,Se){sub 2} solar cells with a device structure of Au/ITO/i-ZnO/CdS/CuIn(S,Se){sub 2}/Mo/soda-lime (SLG) glass were fabricated and characterized. Higher conversion efficiency was obtained for the CuIn(S,Se){sub 2} solar cell with the precursor film deposited at room temperature. The phase and microstructure of the Cu-In-S precursor and the annealed CuIn(S,Se){sub 2} films were examined by X-ray diffraction (XRD) and scanning electron microscopy (SEM). We found that the quality of the CuIn(S,Se){sub 2} films was strongly affected by the deposition temperature of Cu-In-S precursor films. We discuss the grain growth and sintering in CuIn(S,Se){sub 2} films on the basis of the results of XRD and SEM. The highest conversion efficiency of 6.38% (V{sub oc}= 521 mV, J{sub sc}= 22.6 mA cm{sup -2}, FF = 0.541) was obtained for the CuIn(S,Se){sub 2} solar cell with the precursor film deposited at room temperature and post-annealed at 620 C. The solar cell was analyzed by secondary ion mass spectroscopy (SIMS) and transmission electron microscopy (TEM). (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  13. Tim-3 co-stimulation promotes short-lived effector T cells, restricts memory precursors, and is dispensable for T cell exhaustion.

    Science.gov (United States)

    Avery, Lyndsay; Filderman, Jessica; Szymczak-Workman, Andrea L; Kane, Lawrence P

    2018-02-20

    Tim-3 is highly expressed on a subset of T cells during T cell exhaustion in settings of chronic viral infection and tumors. Using lymphocytic choriomeningitis virus (LCMV) Clone 13, a model for chronic infection, we found that Tim-3 was neither necessary nor sufficient for the development of T cell exhaustion. Nonetheless, expression of Tim-3 was sufficient to drive resistance to PD-L1 blockade therapy during chronic infection. Strikingly, expression of Tim-3 promoted the development of short-lived effector T cells, at the expense of memory precursor development, after acute LCMV infection. These effects were accompanied by increased Akt/mTOR signaling in T cells expressing endogenous or ectopic Tim-3. Conversely, Akt/mTOR signaling was reduced in effector T cells from Tim-3-deficient mice. Thus, Tim-3 is essential for optimal effector T cell responses, and may also contribute to exhaustion by restricting the development of long-lived memory T cells. Taken together, our results suggest that Tim-3 is actually more similar to costimulatory receptors that are up-regulated after T cell activation than to a dominant inhibitory protein like PD-1. These findings have significant implications for the development of anti-Tim-3 antibodies as therapeutic agents.

  14. Single Molecular Precursor Solution for CuIn(S,Se)2 Thin Films Photovoltaic Cells: Structure and Device Characteristics.

    Science.gov (United States)

    Tiwari, Devendra; Koehler, Tristan; Lin, Xianzhong; Sarua, Andrei; Harniman, Robert; Wang, Lan; Klenk, Reiner; Fermin, David J

    2017-01-25

    A single molecular precursor solution is described for the deposition of CuIn(S,Se)2 (CIS) film onto Mo-coated glass substrates by spin coating, followed by annealing in Se atmosphere. Characterization of the films by X-ray diffraction, Raman spectroscopy and scanning electron microscopy demonstrates the formation of a highly homogeneous and compact 1.1 μm thick CIS layer, with a MoSe2 under-layer. Atomic force microscopy reveals the presence of spherical grains between 400 and 450 nm, featuring surface corrugation in the range of 30 nm. Film composition is found to be in close agreement with that of the precursor solution. Diffuse reflectance spectroscopy shows a direct band gap (Eg) of 1.36 eV. Intensity and temperature dependence photoluminescence spectra show characteristic features associated with a donor-acceptor pair recombination mechanism, featuring activation energy of 34 meV. Over 85 solar cell devices with the configuration Mo/CIS/CdS/i-ZnO/Al:ZnO/Ni-Al and an total area of 0.5 cm2 were fabricated and tested. The champion cell shows a power efficiency of 3.4% with an open circuit voltage of 521 mV and short circuit current of 14 mA/cm2 under AM 1.5 illumination and an external quantum efficiency above 60%. Overall variation in each of solar cell parameters remains below 10% of the average value, demonstrating the remarkable homogeneity of this solution processing method. To understand the limitation of devices, the dependence of the open-circuit voltage and impedance spectra upon temperature were analyzed. The data reveal that the CuIn(S,Se)2/CdS interface is the main recombination pathway with an activation energy of 0.79 eV as well as the presence of two "bulk" defect states with activation energies of 37 and 122 meV. We also estimated that the MoSe2 under-layer generates back contact barrier of 195 meV.

  15. Expansion and characterization of ventral mesencephalic precursor cells: effect of mitogens and investigation of FA1 as a potential dopaminergic marker

    DEFF Research Database (Denmark)

    Jensen, Pia; Bauer, Matthias; Jensen, Charlotte H

    2007-01-01

    Methods for identification and in vitro expansion of ventral mesencephalic dopaminergic precursor cells are of interest in the search for transplantable neurons for cell therapy in Parkinson's disease (PD). We investigated the potential use of fibroblast growth factor 2 (FGF2) and fibroblast growth...... factor 8 (FGF8) for expansion of such dopaminergic precursor cells, and fetal antigen-1 (FA1), a secreted neuronal protein of unknown function, as a non-invasive dopaminergic marker. Tissue from embryonic day (ED) 12 rat ventral mesencephalon was dissociated mechanically and cultured for 4 days...... in the presence of FGF2, FGF8, or without mitogens (control). After mitogen withdrawal and addition of 0.5% bovine serum, cells were differentiated for 6 days. Before differentiation, significantly more cells incorporated BrdU in cultures exposed to FGF2 (19-fold; P

  16. Precursor States of Brain Tumor Initiating Cell Lines Are Predictive of Survival in Xenografts and Associated with Glioblastoma Subtypes

    Directory of Open Access Journals (Sweden)

    Carlo Cusulin

    2015-07-01

    Full Text Available In glioblastoma multiforme (GBM, brain-tumor-initiating cells (BTICs with cancer stem cell characteristics have been identified and proposed as primordial cells responsible for disease initiation, recurrence, and therapeutic resistance. However, the extent to which individual, patient-derived BTIC lines reflect the heterogeneity of GBM remains poorly understood. Here we applied a stem cell biology approach and compared self-renewal, marker expression, label retention, and asymmetric cell division in 20 BTIC lines. Through cluster analysis, we identified two subgroups of BTIC lines with distinct precursor states, stem- or progenitor-like, predictive of survival after xenograft. Moreover, stem and progenitor transcriptomic signatures were identified, which showed a strong association with the proneural and mesenchymal subtypes, respectively, in the TCGA cohort. This study proposes a different framework for the study and use of BTIC lines and provides precursor biology insights into GBM.

  17. Nanofibers Support Oligodendrocyte Precursor Cell Growth and Function as a Neuron-Free Model for Myelination Study

    Science.gov (United States)

    Li, Yongchao; Ceylan, Muhammet; Shrestha, Bikesh; Wang, Haibo; Lu, Q.Richard; Asmatulu, Ramazan; Yao, Li

    2014-01-01

    Nanofiber-based scaffolds may simultaneously provide immediate contact guidance for neural regeneration and act as a vehicle for therapeutic cell delivery to enhance axonal myelination. Additionally, nanofibers can serve as a neuron-free model to study myelination of oligodendrocytes. In this study, we fabricated nanofibers using a polycaprolactone and gelatin co-polymer. The ratio of the gelatin component in the fibers was confirmed by energy dispersive x-ray spectroscopy. The addition of gelatin to the polycaprolactone (PCL) for nanofiber fabrication decreased the contact angle of the electrospun fibers. We showed that both polycaprolactone nanofibers as well as polycaprolactone and gelatin co-polymer nanofibers can support oligodendrocyte precursor cell (OPC) growth and differentiation. OPCs maintained their phenotype and viability on nanofibers and were induced to differentiate into oligodendrocytes. The differentiated oligodendrocytes extend their processes along the nanofibers and ensheathed the nanofibers. Oligodendrocytes formed significantly more myelinated segments on the PCL and gelatin co3polymer nanofibers than those on PCL nanofibers alone. PMID:24304204

  18. Transplanted Human Stem Cell-Derived Interneuron Precursors Mitigate Mouse Bladder Dysfunction and Central Neuropathic Pain after Spinal Cord Injury.

    Science.gov (United States)

    Fandel, Thomas M; Trivedi, Alpa; Nicholas, Cory R; Zhang, Haoqian; Chen, Jiadong; Martinez, Aida F; Noble-Haeusslein, Linda J; Kriegstein, Arnold R

    2016-10-06

    Neuropathic pain and bladder dysfunction represent significant quality-of-life issues for many spinal cord injury patients. Loss of GABAergic tone in the injured spinal cord may contribute to the emergence of these symptoms. Previous studies have shown that transplantation of rodent inhibitory interneuron precursors from the medial ganglionic eminence (MGE) enhances GABAergic signaling in the brain and spinal cord. Here we look at whether transplanted MGE-like cells derived from human embryonic stem cells (hESC-MGEs) can mitigate the pathological effects of spinal cord injury. We find that 6 months after transplantation into injured mouse spinal cords, hESC-MGEs differentiate into GABAergic neuron subtypes and receive synaptic inputs, suggesting functional integration into host spinal cord. Moreover, the transplanted animals show improved bladder function and mitigation of pain-related symptoms. Our results therefore suggest that this approach may be a valuable strategy for ameliorating the adverse effects of spinal cord injury. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Hemopoietic stem cells in rhesus monkeys : surface antigens, radiosensitivity, and responses to GM-CSF

    NARCIS (Netherlands)

    J.J. Wielenga (Jenne)

    1990-01-01

    textabstractRhesus monkeys (Macaca mulatta) were bred at the Primate Center TNO, Rijswijk, The Netherlands!. Both male and female animals were used for the experiments. The monkeys weighed 2.5-4 kg and were 2-4 years old at the time of the experiment. They were all typed for RhLA-A, -B and -DR

  20. Tumor suppressors BTG1 and IKZF1 cooperate during mouse leukemia development and increase relapse risk in B-cell precursor acute lymphoblastic leukemia patients.

    Science.gov (United States)

    Scheijen, Blanca; Boer, Judith M; Marke, René; Tijchon, Esther; van Ingen Schenau, Dorette; Waanders, Esmé; van Emst, Liesbeth; van der Meer, Laurens T; Pieters, Rob; Escherich, Gabriele; Horstmann, Martin A; Sonneveld, Edwin; Venn, Nicola; Sutton, Rosemary; Dalla-Pozza, Luciano; Kuiper, Roland P; Hoogerbrugge, Peter M; den Boer, Monique L; van Leeuwen, Frank N

    2017-03-01

    Deletions and mutations affecting lymphoid transcription factor IKZF1 (IKAROS) are associated with an increased relapse risk and poor outcome in B-cell precursor acute lymphoblastic leukemia. However, additional genetic events may either enhance or negate the effects of IKZF1 deletions on prognosis. In a large discovery cohort of 533 childhood B-cell precursor acute lymphoblastic leukemia patients, we observed that single-copy losses of BTG1 were significantly enriched in IKZF1 -deleted B-cell precursor acute lymphoblastic leukemia ( P =0.007). While BTG1 deletions alone had no impact on prognosis, the combined presence of BTG1 and IKZF1 deletions was associated with a significantly lower 5-year event-free survival ( P =0.0003) and a higher 5-year cumulative incidence of relapse ( P =0.005), when compared with IKZF1 -deleted cases without BTG1 aberrations. In contrast, other copy number losses commonly observed in B-cell precursor acute lymphoblastic leukemia, such as CDKN2A/B, PAX5, EBF1 or RB1 , did not affect the outcome of IKZF1 -deleted acute lymphoblastic leukemia patients. To establish whether the combined loss of IKZF1 and BTG1 function cooperate in leukemogenesis, Btg1 -deficient mice were crossed onto an Ikzf1 heterozygous background. We observed that loss of Btg1 increased the tumor incidence of Ikzf1 +/- mice in a dose-dependent manner. Moreover, murine B cells deficient for Btg1 and Ikzf1 +/- displayed increased resistance to glucocorticoids, but not to other chemotherapeutic drugs. Together, our results identify BTG1 as a tumor suppressor in leukemia that, when deleted, strongly enhances the risk of relapse in IKZF1 -deleted B-cell precursor acute lymphoblastic leukemia, and augments the glucocorticoid resistance phenotype mediated by the loss of IKZF1 function. Copyright© Ferrata Storti Foundation.

  1. Live cell monitoring of mu-opioid receptor-mediated G-protein activation reveals strong biological activity of close morphine biosynthetic precursors.

    Science.gov (United States)

    Nikolaev, Viacheslav O; Boettcher, Chotima; Dees, Christian; Bünemann, Moritz; Lohse, Martin J; Zenk, Meinhart H

    2007-09-14

    G-protein activation by receptors is generally measured using (35)S-GTPgammaS binding assays in cell membranes and cannot be well assessed in intact cells. We have recently developed a fluorescence resonance energy transfer (FRET)-based approach to monitor G(i)-protein activation in living cells. Here we report that this technique can be used to determine structure-activity relationships of receptor agonists in intact cells. We have recently shown that morphine is biosynthesized de novo by mammals via a multistep pathway different from that in plants. However, the pharmacological properties of morphine precursors are poorly understood. Here, we directly monitored mu-opioid receptor (MOR)-mediated G(i)-protein activation in living cells by FRET and validated this method with classical GTPgammaS binding assays. Receptor binding studies and FRET measurements demonstrated that several (R)-configurated morphine precursors such as (R)-reticuline, salutaridine, salutaridinol, thebaine, and codeine were partial MOR agonists. Some closer precursors such as oripavine, codeinone, and morphinone activated G(i)-proteins as strongly as morphine, but with slightly lower potencies. The more distant the precursors were positioned in the pathway with respect to morphine, the less efficient and potent they were at MOR. Comparison of pharmacological properties of close morphine precursors and concentrations in which they occur in animal tissues suggests that they might activate MOR signaling under physiological conditions. Taken together, our data indicate that FRET-based assays of G-protein activation can serve to determine the abilities of compounds to activate G-protein signaling directly and in living cells.

  2. Hair Follicle and Sebaceous Gland De Novo Regeneration With Cultured Epidermal Stem Cells and Skin-Derived Precursors.

    Science.gov (United States)

    Wang, Xiaoxiao; Wang, Xusheng; Liu, Jianjun; Cai, Ting; Guo, Ling; Wang, Shujuan; Wang, Jinmei; Cao, Yanpei; Ge, Jianfeng; Jiang, Yuyang; Tredget, Edward E; Cao, Mengjun; Wu, Yaojiong

    2016-12-01

    : Stem cell-based organ regeneration is purported to enable the replacement of impaired organs in the foreseeable future. Here, we demonstrated that a combination of cultured epidermal stem cells (Epi-SCs) derived from the epidermis and skin-derived precursors (SKPs) was capable of reconstituting functional hair follicles and sebaceous glands (SG). When Epi-SCs and SKPs were mixed in a hydrogel and implanted into an excisional wound in nude mice, the Epi-SCs formed de novo epidermis along with hair follicles, and SKPs contributed to dermal papilla in the neogenic hair follicles. Notably, a combination of culture-expanded Epi-SCs and SKPs derived from the adult human scalp were sufficient to generate hair follicles and hair. Bone morphogenetic protein 4, but not Wnts, sustained the expression of alkaline phosphatase in SKPs in vitro and the hair follicle-inductive property in vivo when SKPs were engrafted with neonatal epidermal cells into excisional wounds. In addition, Epi-SCs were capable of differentiating into sebocytes and formed de novo SGs, which excreted lipids as do normal SGs. Thus our results indicate that cultured Epi-SCs and SKPs are sufficient to generate de novo hair follicles and SGs, implying great potential to develop novel bioengineered skin substitutes with appendage genesis capacity. In postpartum humans, skin appendages lost in injury are not regenerated, despite the considerable achievement made in skin bioengineering. In this study, transplantation of a combination of culture-expanded epidermal stem cells and skin-derived progenitors from mice and adult humans led to de novo regeneration of functional hair follicles and sebaceous glands. The data provide transferable knowledge for the development of novel bioengineered skin substitutes with epidermal appendage regeneration capacity. ©AlphaMed Press.

  3. Chondroitinase and growth factors enhance activation and oligodendrocyte differentiation of endogenous neural precursor cells after spinal cord injury.

    Directory of Open Access Journals (Sweden)

    Soheila Karimi-Abdolrezaee

    Full Text Available The adult spinal cord harbours a population of multipotent neural precursor cells (NPCs with the ability to replace oligodendrocytes. However, despite this capacity, proliferation and endogenous remyelination is severely limited after spinal cord injury (SCI. In the post-traumatic microenvironment following SCI, endogenous spinal NPCs mainly differentiate into astrocytes which could contribute to astrogliosis that exacerbate the outcomes of SCI. These findings emphasize a key role for the post-SCI niche in modulating the behaviour of spinal NPCs after SCI. We recently reported that chondroitin sulphate proteoglycans (CSPGs in the glial scar restrict the outcomes of NPC transplantation in SCI by reducing the survival, migration and integration of engrafted NPCs within the injured spinal cord. These inhibitory effects were attenuated by administration of chondroitinase (ChABC prior to NPC transplantation. Here, in a rat model of compressive SCI, we show that perturbing CSPGs by ChABC in combination with sustained infusion of growth factors (EGF, bFGF and PDGF-AA optimize the activation and oligodendroglial differentiation of spinal NPCs after injury. Four days following SCI, we intrathecally delivered ChABC and/or GFs for seven days. We performed BrdU incorporation to label proliferating cells during the treatment period after SCI. This strategy increased the proliferation of spinal NPCs, reduced the generation of new astrocytes and promoted their differentiation along an oligodendroglial lineage, a prerequisite for remyelination. Furthermore, ChABC and GF treatments enhanced the response of non-neural cells by increasing the generation of new vascular endothelial cells and decreasing the number of proliferating macrophages/microglia after SCI. In conclusions, our data strongly suggest that optimization of the behaviour of endogenous spinal NPCs after SCI is critical not only to promote endogenous oligodendrocyte replacement, but also to reverse

  4. Serial in vivo positive contrast MRI of iron oxide-labeled embryonic stem cell-derived cardiac precursor cells in a mouse model of myocardial infarction.

    Science.gov (United States)

    Mani, Venkatesh; Adler, Eric; Briley-Saebo, Karen C; Bystrup, Anne; Fuster, Valentin; Keller, Gordon; Fayad, Zahi A

    2008-07-01

    Myocardial regeneration with stem-cell transplantation is a possible treatment option to reverse deleterious effects that occur after myocardial infarction. Since little is known about stem cell survival after transplantation, developing techniques for "tracking" cells would be desirable. Iron-oxide-labeled stem cells have been used for in vivo tracking using MRI but produce negative contrast images that are difficult to interpret. The aim of the current study was to test a positive contrast MR technique using reduced z-gradient rephasing (GRASP) to aid in dynamically tracking stem cells in an in vivo model of mouse myocardial infraction. Ferumoxides and protamine sulfate were complexed and used to magnetically label embryonic stem cell-derived cardiac-precursor-cells (ES-CPCs). A total of 500,000 ES-CPCs were injected in the border zone of infarcted mice and MR imaging was performed on a 9.4T scanner using T(2)*-GRE sequences (negative contrast) and positive contrast GRASP technique before, 24 hours, and 1 week after ES-CPC implantation. Following imaging, mice were sacrificed for histology and Perl's staining was used to confirm iron within myocardium. Good correlation was observed between signal loss seen on conventional T(2)* images, bright areas on GRASP, and the presence of iron on histology. This demonstrated the feasibility of in vivo stem cell imaging with positive contrast MRI. (c) 2008 Wiley-Liss, Inc.

  5. What is the relevance of Ikaros gene deletions as a prognostic marker in pediatric Philadelphia-negative B-cell precursor acute lymphoblastic leukemia?

    National Research Council Canada - National Science Library

    Chiara Palmi; Maria Grazia Valsecchi; Giulia Longinotti; Daniela Silvestri; Valentina Carrino; Valentino Conter; Giuseppe Basso; Andrea Biondi; Geertruy Te Kronnie; Giovanni Cazzaniga

    2013-01-01

    .... We focused our analysis on Ikaros (IKZF1) gene deletions in a homogeneous cohort of 410 pediatric patients with Philadelphia chromosome-negative, B-cell precursor acute lymphoblastic leukemia enrolled in Italy into the AIEOP-BFM ALL2000 study...

  6. Selective in vitro expansion of HLA class I-restricted HIV-1 gag-specific CD8+ T cells: cytotoxic T-lymphocyte epitopes and precursor frequencies.

    NARCIS (Netherlands)

    C.A. van Baalen (Carel); M.R. Klein (Michèl); A.M. Geretti (Anna Maria); R.I.P.M. Keet; F. Miedema (Frank); C.A.C.M. van Els (Cécile); A.D.M.E. Osterhaus (Albert)

    1993-01-01

    textabstractOBJECTIVE: To identify HIV-1 Gag cytotoxic T-lymphocyte (CTL) epitopes and HLA restriction of their recognition, and to define precursor frequencies of HIV-1 Gag-specific CTL in the blood of seropositive individuals. METHODS: B-lymphoblastoid cell lines (B-LCL) infected with recombinant

  7. Transcription factor complex formation and chromatin fine structure alterations at the murine c-fms (CSF-1 receptor) locus during maturation of myeloid precursor cells

    NARCIS (Netherlands)

    Tagoh, H; Himes, R; Clarke, D; Leenen, PJM; Riggs, AD; Hume, D; Bonifer, C

    2002-01-01

    Expression of the gene for the macrophage colony stimulating factor receptor (CSF-1R), c-fms, has been viewed as a hallmark of the commitment of multipotent precursor cells to macrophages. Lineage-restricted expression of the gene is controlled by conserved elements in the proximal promoter and

  8. Quiescence and activation of stem and precursor cell populations in the subependymal zone of the mammalian brain are associated with distinct cellular and extracellular matrix signals

    Science.gov (United States)

    The subependymal zone (SEZ) of the lateral ventricles is one of the areas of the adult brain where new neurons are continuously generated from neural stem cells (NSCs), via rapidly dividing precursors. This neurogenic niche is a complex cellular and extracellular microenvironment, highly vascularize...

  9. Minocycline Directly Enhances the Self-Renewal of Adult Neural Precursor Cells.

    Science.gov (United States)

    Kuroda, Anri; Fuchigami, Takahiro; Fuke, Satoshi; Koyama, Natsu; Ikenaka, Kazuhiro; Hitoshi, Seiji

    2017-10-28

    Minocycline not only has antibacterial action but also produces a variety of pharmacological effects. It has drawn considerable attention as a therapeutic agent for symptoms caused by inflammation in many neurological disorders, leading to several clinical trials. Although some of these effects are mediated through its function of suppressing microglial activation, it is not clear whether minocycline acts on other cell types in the adult brain. In this study, we utilized a colony-forming neurosphere assay, in which neural stem cells (NSCs) clonally proliferate to form floating colonies, called neurospheres. We found that minocycline (at therapeutically relevant concentrations in cerebrospinal fluid) enhances the self-renewal capability of NSCs derived from the subependymal zone of adult mouse brain and facilitates their differentiation into oligodendrocytes. Importantly, these effects were independent of a suppression of microglial activation and were specifically observed with minocycline (among tetracycline derivatives). In addition, the size of the NSC population in the adult brain was increased when minocycline was infused into the lateral ventricle by an osmotic minipump in vivo. While precise molecular mechanisms of how minocycline alters the behavior of adult NSCs remain unknown, our data provide a basis for the clinical use of minocycline to treat neurodegenerative and demyelinating diseases.

  10. Hypoxia-elicited impairment of cell wall integrity, glycosylation precursor synthesis, and growth in scaled-up high-cell density fed-batch cultures of Saccharomyces cerevisiae.

    Science.gov (United States)

    Aon, Juan C; Sun, Jianxin; Leighton, Julie M; Appelbaum, Edward R

    2016-08-15

    In this study we examine the integrity of the cell wall during scale up of a yeast fermentation process from laboratory scale (10 L) to industrial scale (10,000 L). In a previous study we observed a clear difference in the volume fraction occupied by yeast cells as revealed by wet cell weight (WCW) measurements between these scales. That study also included metabolite analysis which suggested hypoxia during scale up. Here we hypothesize that hypoxia weakens the yeast cell wall during the scale up, leading to changes in cell permeability, and/or cell mechanical resistance, which in turn may lead to the observed difference in WCW. We tested the cell wall integrity by probing the cell wall sensitivity to Zymolyase. Also exometabolomics data showed changes in supply of precursors for the glycosylation pathway. The results show a more sensitive cell wall later in the production process at industrial scale, while the sensitivity at early time points was similar at both scales. We also report exometabolomics data, in particular a link with the protein glycosylation pathway. Significantly lower levels of Man6P and progressively higher GDP-mannose indicated partially impaired incorporation of this sugar nucleotide during co- or post-translational protein glycosylation pathways at the 10,000 L compared to the 10 L scale. This impairment in glycosylation would be expected to affect cell wall integrity. Although cell viability from samples obtained at both scales were similar, cells harvested from 10 L bioreactors were able to re-initiate growth faster in fresh shake flask media than those harvested from the industrial scale. The results obtained help explain the WCW differences observed at both scales by hypoxia-triggered weakening of the yeast cell wall during the scale up.

  11. [Outcome of treatment of anal squamous cell carcinoma and its precursor in HIV-infected patients].

    Science.gov (United States)

    Nadal, Sidney Roberto; Horta, Sergio Henrique Couto; Calore, Edenilson Eduardo; Manzione, Carmen Ruth

    2007-01-01

    Incidence of anal squamous cell carcinoma is increasing mainly among HIV-positive patients. Treatment consists of radiotherapy and chemotherapy, sometimes followed by tumor resection. The objective was to evaluate the follow-up of such patients to verify recurrences and evolution from HAIN to cancer. This is a report of cases treated at the "Instituto de Infectologia Emílio Ribas", Sao Paulo, Brazil. We attended 45 HIV-positive patients between July 1996 and June 2006. Most were male (97.7%), with ages ranging from 23 to 55 years (mean: 38.5 years). Thirty patients had high grade anal intra-epithelial neoplasia (HAIN), treated with local resection, and 15 with anal canal invasive squamous cell carcinoma were first submitted to chemo radiation, while biopsies were obtained during follow-up. Patients with HAIN had recurrences in 16.7% of cases and remained cancer free for up to five years. Chemoradiation was not possible in five patients with invasive carcinoma (40%) because three had advanced AIDS and two refused treatment. Eight (88.8%) out of nine patients had complete response to chemoradiation and remained cancer free for a period from three to six years. Chemoradiation failed in the ninth patient: abdominal perineal resection was performed, and there was no recurrence over a five-year period. We concluded that HAIN can recur after local resection in HIV-positive patients but does not evolve to invasive carcinoma. Invasive cancer can be treated in the same way as in HIV seronegative persons, when clinical conditions permit.

  12. Alloreactive and leukemia-reactive T cells are preferentially derived from naive precursors in healthy donors: implications for immunotherapy with memory T cells.

    Science.gov (United States)

    Distler, Eva; Bloetz, Andrea; Albrecht, Jana; Asdufan, Saliha; Hohberger, Alexander; Frey, Michaela; Schnürer, Elke; Thomas, Simone; Theobald, Matthias; Hartwig, Udo F; Herr, Wolfgang

    2011-07-01

    HLA mismatch antigens are major targets of alloreactive T cells in HLA-incompatible stem-cell transplantation, which can trigger severe graft-versus-host disease and reduce survival in transplant recipients. Our objective was to identify T-cell subsets with reduced in vitro reactivity to allogeneic HLA antigens. We sorted CD4 and CD8 T-cell subsets from peripheral blood by flow cytometry according to their expression of naive and memory markers CD45RA, CD45RO, CD62L, and CCR7. Subsets were defined by a single marker to facilitate future establishment of a clinical-grade procedure for reducing alloreactive T-cell precursors and graft-versus-host disease. T cells were stimulated in mixed lymphocyte reactions against HLA-deficient K562 cells transfected with single HLA-A/-B/-C/-DR/-DQ mismatch alleles. Alloreactivity was measured by interferon-γ spot production and cell proliferation. We observed that allogeneic HLA-reactivity was preferentially derived from subsets enriched for naïve T cells rather than memory T cells in healthy donors, irrespective of the HLA mismatch allele. This separation was most efficient if CD45RA (versus other markers) was used for sorting. The numbers of allogeneic HLA-reactive effector cells were in median 7.2-fold and 16.6-fold lower in CD45RA(neg) memory CD8 and CD4 T cells than in entire CD8 and CD4 T cells, respectively. In contrast, proliferation of memory T cells in response to allogeneic HLA was more variably reduced (CD8) or equivalent (CD4) when compared to that of naïve T cells. We also demonstrated in HLA-matched donor-patient pairs that leukemia-reactive CD8 cytotoxic T-lymphocytes were mainly derived from subsets enriched for naïve T cells compared to memory T cells. Memory T-cell subsets of most healthy individuals showed decreased allogeneic HLA-reactivity, but lacked significant anti-leukemia responses in vitro. The clinical use of memory or naïve-depleted T cells might be beneficial for HLA-mismatched patients at high

  13. Reversible immortalization of Nestin-positive precursor cells from pancreas and differentiation into insulin-secreting cells

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Pei; Li, Li; Qi, Hui [The Clinical Medical Research Center, The Second Clinical Medical College (Shenzhen People' s Hospital), Jinan University, 518020 Shenzhen (China); Zhou, Han-xin [Department of General Surgery, First Hospital (Shenzhen Second People' s Hospital) of Shenzhen University, 518020 Shenzhen (China); Deng, Chun-yan [The Clinical Medical Research Center, The Second Clinical Medical College (Shenzhen People' s Hospital), Jinan University, 518020 Shenzhen (China); Li, Fu-rong, E-mail: frli62@yahoo.com [The Clinical Medical Research Center, The Second Clinical Medical College (Shenzhen People' s Hospital), Jinan University, 518020 Shenzhen (China); Shenzhen Institution of Gerontology, 518020 Shenzhen (China)

    2012-02-10

    Highlights: Black-Right-Pointing-Pointer The NPPCs from mouse pancreas were isolated. Black-Right-Pointing-Pointer Tet-on system for SV40 large in NPPCs was used to get RINPPCs. Black-Right-Pointing-Pointer The RINPPCs can undergo at least 80 population doublings without senescence. Black-Right-Pointing-Pointer The RINPPCs can be induced to differentiate into insulin-producing cells. Black-Right-Pointing-Pointer The combination of GLP-1 and sodium butyrate promoted the differentiation process. -- Abstract: Pancreatic stem cells or progenitor cells posses the ability of directed differentiation into pancreatic {beta} cells. However, these cells usually have limited proliferative capacity and finite lifespan in vitro. In the present study, Nestin-positive progenitor cells (NPPCs) from mouse pancreas that expressed the pancreatic stem cells or progenitor cell marker Nestin were isolated to obtain a sufficient number of differentiated pancreatic {beta} cells. Tet-on system for SV40 large T-antigen expression in NPPCs was used to achieve reversible immortalization. The reversible immortal Nestin-positive progenitor cells (RINPPCs) can undergo at least 80 population doublings without senescence in vitro while maintaining their biological and genetic characteristics. RINPPCs can be efficiently induced to differentiate into insulin-producing cells that contain a combination of glucagon-like peptide-1 (GLP-1) and sodium butyrate. The results of the present study can be used to explore transplantation therapy of type I diabetes mellitus.

  14. Inhibition of phosphodiesterase-4 promotes oligodendrocyte precursor cell differentiation and enhances CNS remyelination

    Science.gov (United States)

    Syed, Yasir A; Baer, Alexandra; Hofer, Matthias P; González, Ginez A; Rundle, Jon; Myrta, Szymon; Huang, Jeffrey K; Zhao, Chao; Rossner, Moritz J; Trotter, Matthew W B; Lubec, Gert; Franklin, Robin J M; Kotter, Mark R

    2013-01-01

    The increasing effectiveness of new disease-modifying drugs that suppress disease activity in multiple sclerosis has opened up opportunities for regenerative medicines that enhance remyelination and potentially slow disease progression. Although several new targets for therapeutic enhancement of remyelination have emerged, few lend themselves readily to conventional drug development. Here, we used transcription profiling to identify mitogen-activated protein kinase (Mapk) signalling as an important regulator involved in the differentiation of oligodendrocyte progenitor cells (OPCs) into oligodendrocytes. We show in tissue culture that activation of Mapk signalling by elevation of intracellular levels of cyclic adenosine monophosphate (cAMP) using administration of either dibutyryl-cAMP or inhibitors of the cAMP-hydrolysing enzyme phosphodiesterase-4 (Pde4) enhances OPC differentiation. Finally, we demonstrate that systemic delivery of a Pde4 inhibitor leads to enhanced differentiation of OPCs within focal areas of toxin-induced demyelination and a consequent acceleration of remyelination. These data reveal a novel approach to therapeutic enhancement of remyelination amenable to pharmacological intervention and hence with significant potential for translation. PMID:24293318

  15. Inhibition of phosphodiesterase-4 promotes oligodendrocyte precursor cell differentiation and enhances CNS remyelination.

    Science.gov (United States)

    Syed, Yasir A; Baer, Alexandra; Hofer, Matthias P; González, Ginez A; Rundle, Jon; Myrta, Szymon; Huang, Jeffrey K; Zhao, Chao; Rossner, Moritz J; Trotter, Matthew W B; Lubec, Gert; Franklin, Robin J M; Kotter, Mark R

    2013-12-01

    The increasing effectiveness of new disease-modifying drugs that suppress disease activity in multiple sclerosis has opened up opportunities for regenerative medicines that enhance remyelination and potentially slow disease progression. Although several new targets for therapeutic enhancement of remyelination have emerged, few lend themselves readily to conventional drug development. Here, we used transcription profiling to identify mitogen-activated protein kinase (Mapk) signalling as an important regulator involved in the differentiation of oligodendrocyte progenitor cells (OPCs) into oligodendrocytes. We show in tissue culture that activation of Mapk signalling by elevation of intracellular levels of cyclic adenosine monophosphate (cAMP) using administration of either dibutyryl-cAMP or inhibitors of the cAMP-hydrolysing enzyme phosphodiesterase-4 (Pde4) enhances OPC differentiation. Finally, we demonstrate that systemic delivery of a Pde4 inhibitor leads to enhanced differentiation of OPCs within focal areas of toxin-induced demyelination and a consequent acceleration of remyelination. These data reveal a novel approach to therapeutic enhancement of remyelination amenable to pharmacological intervention and hence with significant potential for translation. © 2013 The Authors. Published by John Wiley and Sons, Ltd on behalf of EMBO.

  16. Targeted deletion of Hand2 in enteric neural precursor cells affects its functions in neurogenesis, neurotransmitter specification and gangliogenesis, causing functional aganglionosis

    Science.gov (United States)

    Lei, Jun; Howard, Marthe J.

    2011-01-01

    Targeted deletion of the bHLH DNA-binding protein Hand2 in the neural crest, impacts development of the enteric nervous system (ENS), possibly by regulating the transition from neural precursor cell to neuron. We tested this hypothesis by targeting Hand2 deletion in nestin-expressing neural precursor (NEP) cells. The mutant mice showed abnormal ENS development, resulting in lethal neurogenic pseudo-obstruction. Neurogenesis of neurons derived from NEP cells identified a second nestin non-expressing neural precursor (NNEP) cell in the ENS. There was substantial compensation for the loss of neurons derived from the NEP pool by the NNEP pool but this was insufficient to abrogate the negative impact of Hand2 deletion. Hand2-mediated regulation of proliferation affected both neural precursor and neuron numbers. Differentiation of glial cells derived from the NEP cells was significantly decreased with no compensation from the NNEP pool of cells. Our data indicate differential developmental potential of NEPs and NNEPs; NNEPs preferentially differentiate as neurons, whereas NEPs give rise to both neurons and glial cells. Deletion of Hand2 also resulted in complete loss of NOS and VIP and a significant decrease in expression of choline acetyltransferase and calretinin, demonstrating a role for Hand2 in neurotransmitter specification and/or expression. Loss of Hand2 resulted in a marked disruption of the developing neural network, exemplified by lack of a myenteric plexus and extensive overgrowth of fibers. Thus, Hand2 is essential for neurogenesis, neurotransmitter specification and neural network patterning in the developing ENS. PMID:21989918

  17. Identification of potential biomarkers of hepatitis B-induced acute liver failure using hepatic cells derived from human skin precursors.

    Science.gov (United States)

    Rodrigues, Robim M; Sachinidis, Agapios; De Boe, Veerle; Rogiers, Vera; Vanhaecke, Tamara; De Kock, Joery

    2015-09-01

    Besides their role in the elucidation of pathogenic processes of medical and pharmacological nature, biomarkers can also be used to document specific toxicological events. Hepatic cells generated from human skin-derived precursors (hSKP-HPC) were previously shown to be a promising in vitro tool for the evaluation of drug-induced hepatotoxicity. In this study, their capacity to identify potential liver-specific biomarkers at the gene expression level was investigated with particular emphasis on acute liver failure (ALF). To this end, a set of potential ALF-specific biomarkers was established using clinically relevant liver samples obtained from patients suffering from hepatitis B-associated ALF. Subsequently, this data was compared to data obtained from primary human hepatocyte cultures and hSKP-HPC, both exposed to the ALF-inducing reference compound acetaminophen. It was found that both in vitro systems revealed a set of molecules that was previously identified in the ALF liver samples. Yet, only a limited number of molecules was common between both in vitro systems and the ALF liver samples. Each of the in vitro systems could be used independently to identify potential toxicity biomarkers related to ALF. It seems therefore more appropriate to combine primary human hepatocyte cultures with complementary in vitro models to efficiently screen out potential hepatotoxic compounds. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Development of plurimetallic electrocatalysts prepared by decomposition of polymeric precursors for EtOH/O{sub 2} fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Palma, Livia M.; Almeida, Thiago S.; Andrade, Adalgisa R. de, E-mail: ardandra@ffclrp.usp.br [Departamento de Quimica, Faculdade de Filosofia, Ciencias e Letras de Ribeirao Preto, Universidade de Sao Paulo, Ribeirao Preto, SP (Brazil)

    2012-03-15

    This work aimed to develop plurimetallic electrocatalysts composed of Pt, Ru, Ni, and Sn supported on C by decomposition of polymeric precursors (DPP), at a constant metal:carbon ratio of 40:60 wt.%, for application in direct ethanol fuel cell (DEFC). The obtained nanoparticles were physico-chemically characterized by X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDX). XRD results revealed a face-centered cubic crystalline Pt with evidence that Ni, Ru, and Sn atoms were incorporated into the Pt structure. Electrochemical characterization of the nanoparticles was accomplished by cyclic voltammetry (CV) and chronoamperometry (CA) in slightly acidic medium (0.05 mol L{sup -1}H{sub 2}SO{sub 4}), in the absence and presence of ethanol. Addition of Sn to PtRuNi/C catalysts significantly shifted the ethanol and CO onset potentials toward lower values, thus increasing the catalytic activity, especially for the quaternary composition Pt{sub 64}Sn{sub 15}Ru{sub 13}Ni{sub 8}/C. Electrolysis of ethanol solutions at 0.4 V vs. RHE allowed determination of acetaldehyde and acetic acid as the main reaction products. The presence of Ru in alloys promoted formation of acetic acid as the main product of ethanol oxidation. The Pt{sub 64}Sn{sub 15}Ru{sub 13}Ni{sub 8}/C catalyst displayed the best performance for DEFC. (author)

  19. Chondroitin sulfate proteoglycans regulate the growth, differentiation and migration of multipotent neural precursor cells through the integrin signaling pathway

    Directory of Open Access Journals (Sweden)

    Lü He-Zuo

    2009-10-01

    Full Text Available Abstract Background Neural precursor cells (NPCs are defined by their ability to proliferate, self-renew, and retain the potential to differentiate into neurons and glia. Deciphering the factors that regulate their behaviors will greatly aid in their use as potential therapeutic agents or targets. Chondroitin sulfate proteoglycans (CSPGs are prominent components of the extracellular matrix (ECM in the central nervous system (CNS and are assumed to play important roles in controlling neuronal differentiation and development. Results In the present study, we demonstrated that CSPGs were constitutively expressed on the NPCs isolated from the E16 rat embryonic brain. When chondroitinase ABC was used to abolish the function of endogenous CSPGs on NPCs, it induced a series of biological responses including the proliferation, differentiation and migration of NPCs, indicating that CSPGs may play a critical role in NPC development and differentiation. Finally, we provided evidence suggesting that integrin signaling pathway may be involved in the effects of CSPGs on NPCs. Conclusion The present study investigating the influence and mechanisms of CSPGs on the differentiation and migration of NPCs should help us to understand the basic biology of NPCs during CNS development and provide new insights into developing new strategies for the treatment of the neurological disorders in the CNS.

  20. Modeling the evolution of ETV6-RUNX1-induced B-cell precursor acute lymphoblastic leukemia in mice.

    Science.gov (United States)

    van der Weyden, Louise; Giotopoulos, George; Rust, Alistair G; Matheson, Louise S; van Delft, Frederik W; Kong, Jun; Corcoran, Anne E; Greaves, Mel F; Mullighan, Charles G; Huntly, Brian J; Adams, David J

    2011-07-28

    The t(12;21) translocation that generates the ETV6-RUNX1 (TEL-AML1) fusion gene, is the most common chromosomal rearrangement in childhood cancer and is exclusively associated with B-cell precursor acute lymphoblastic leukemia (BCP-ALL). The translocation arises in utero and is necessary but insufficient for the development of leukemia. Single-nucleotide polymorphism array analysis of ETV6-RUNX1 patient samples has identified multiple additional genetic alterations; however, the role of these lesions in leukemogenesis remains undetermined. Moreover, murine models of ETV6-RUNX1 ALL that faithfully recapitulate the human disease are lacking. To identify novel genes that cooperate with ETV6-RUNX1 in leukemogenesis, we generated a mouse model that uses the endogenous Etv6 locus to coexpress the Etv6-RUNX1 fusion and Sleeping Beauty transposase. An insertional mutagenesis screen was performed by intercrossing these mice with those carrying a Sleeping Beauty transposon array. In contrast to previous models, a substantial proportion (20%) of the offspring developed BCP-ALL. Isolation of the transposon insertion sites identified genes known to be associated with BCP-ALL, including Ebf1 and Epor, in addition to other novel candidates. This is the first mouse model of ETV6-RUNX1 to develop BCP-ALL and provides important insight into the cooperating genetic alterations in ETV6-RUNX1 leukemia.

  1. Overexpression of Polysialylated Neural Cell Adhesion Molecule Improves the Migration Capacity of Induced Pluripotent Stem Cell-Derived Oligodendrocyte Precursors

    NARCIS (Netherlands)

    Czepiel, Marcin; Leicher, Lasse; Becker, Katja; Boddeke, Erik; Copray, Sjef

    Cell replacement therapy aiming at the compensation of lost oligodendrocytes and restoration of myelination in acquired or congenital demyelination disorders has gained considerable interest since the discovery of induced pluripotent stem cells (iPSCs). Patient-derived iPSCs provide an inexhaustible

  2. Association between CTL precursor frequency to HLA-C mismatches and HLA-C antigen cell surface expression

    Directory of Open Access Journals (Sweden)

    Moshe eIsraeli

    2014-10-01

    Full Text Available Previous studies showed the relevance of the cytotoxic T cell precursor frequency assay (CTLp for prediction of the outcome of HLA mismatched hematopoietic cell transplantation (HCT. Recently it has been shown that HLA-C cell surface expression is correlated with virus specific cytotoxic T cell responses and viremia control in HIV patients.The aim of the current study was to investigate the association between HLA-C antigen expression and the CTLp frequency to the mismatched HLA-C antigen.In total 115 recipient–donor pairs, for whom a successful CTLp assay was performed, were evaluated for this pilot study. All donor-recipient pairs were matched at 9/10 alleles with a single mismatch at the HLA-C locus. Antigen expression level of the mismatched HLA-C allele for each recipient and donor was based on the MFI values as described by Apps et al (Science, 2013.The cell surface expression of recipient’s mismatched HLA-C antigen was significantly lower among CTLp negative (n=59 compared to CTLp positive (n=56 pairs (154 and 193 MFI units, respectively; p=0.0031. This difference was more pronounced in donor-recipient pairs that were mismatched for amino-acid residue-116 located in the groove of the HLA-C antigen, suggesting the importance of peptide binding in the allo-recognition. Furthermore, in the particular case of low expression of the recipient mismatched HLA-C antigen (MFI<115, CTLp reactivity depended on HLA-C expression level in the donor; the median MFI of donor’s mismatched HLA-C antigen was 114 in CTLp negative cases (n=26, while in CTLp positive cases (n=15 the median MFI of donor’s HLA-C antigen was 193. (P=0.0093.We conclude that the expression level of the donor and recipient mismatched HLA-C antigens affect CTLp outcome. HLA-C antigen expression levels in combination with the CTLp assay may prove useful for the prediction of the clinical outcome of HLA-C mismatched HCT.

  3. 1,25-dihydroxyvitamin D3 increases the transplantation success of human muscle precursor cells in SCID mice.

    Science.gov (United States)

    Stephan, Lionel; Bouchentouf, Manaf; Mills, Philippe; Lafreniere, Jean-François; Tremblay, Jacques P

    2007-01-01

    Human muscle precursor cell (hMPC) transplantation is a potential therapy for severe muscle trauma or myopathies. Some previous studies demonstrated that 1,25-dihydroxyvitamin-D3 (1,25-D3) acted directly on myoblasts, regulating their proliferation and fusion. 1,25-D3 is also involved in apoptosis modulation of other cell types and may thus contribute to protect the transplanted hMPCs. We have therefore investigated whether 1,25-D3 could improve the hMPC graft success. The 1,25-D3 effects on hMPC proliferation, fusion, and survival were initially monitored in vitro. hMPCs were also grafted in the tibialis anterior of SCID mice treated or not with 1,25-D3 to determine its in vivo effect. Graft success, proliferation, and viability of transplanted hMPCs were evaluated. 1,25-D3 enhanced proliferation and fusion of hMPCs in vitro and in vivo. However, 1,25-D3 did not protect hMPCs from various proapoptotic factors (in vitro) or during the early posttransplantation period. 1,25-D3 enhanced hMPC graft success because the number of muscle fibers expressing human dystrophin was significantly increased in the TA sections of 1,25-D3-treated mice (166.75 +/- 20.64) compared to the control mice (97.5 +/- 16.58). This result could be partly attributed to the improvement of the proliferation and differentiation of hMPCs in the presence of 1,25-D3. Thus, 1,25-D3 administration could improve the clinical potential of hMPC transplantation currently developed for muscle trauma or myopathies.

  4. Impact of cytogenetic abnormalities in adults with Ph-negative B-cell precursor acute lymphoblastic leukemia.

    Science.gov (United States)

    Lafage-Pochitaloff, Marina; Baranger, Laurence; Hunault, Mathilde; Cuccuini, Wendy; Lefebvre, Christine; Bidet, Audrey; Tigaud, Isabelle; Eclache, Virginie; Delabesse, Eric; Bilhou-Nabéra, Chrystèle; Terré, Christine; Chapiro, Elise; Gachard, Nathalie; Mozziconacci, Marie-Joelle; Ameye, Geneviève; Porter, Sarah; Grardel, Nathalie; Béné, Marie C; Chalandon, Yves; Graux, Carlos; Huguet, Françoise; Lhéritier, Véronique; Ifrah, Norbert; Dombret, Hervé

    2017-10-19

    Multiple cytogenetic subgroups have been described in adult Philadelphia chromosome (Ph)-negative B-cell precursor (BCP) acute lymphoblastic leukemia (ALL), often comprising small numbers of patients. In this study, we aimed to reassess the prognostic value of cytogenetic abnormalities in a large series of 617 adult patients with Ph-negative BCP-ALL (median age, 38 years), treated in the intensified Group for Research on Adult Acute Lymphoblastic Leukemia (GRAALL)-2003/2005 trials. Combined data from karyotype, DNA index, fluorescence in situ hybridization, and polymerase chain reaction screening for relevant abnormalities were centrally reviewed and were informative in 542 cases (88%), allowing classification in 10 exclusive primary cytogenetic subgroups and in secondary subgroups, including complex and monosomal karyotypes. Prognostic analyses focused on cumulative incidence of failure (including primary refractoriness and relapse), event-free survival, and overall survival. Only 2 subgroups, namely t(4;11)/ KMT2A-AFF1 and 14q32/ IGH translocations, displayed a significantly worse outcome in this context, still observed after adjustment for age and after censoring patients who received allogeneic stem cell transplantation (SCT) in first remission at SCT time. A worse outcome was also observed in patients with low hypodiploidy/near triploidy, but this was likely related to their higher age and worse tolerance to therapy. The other cytogenetic abnormalities, including complex and monosomal karyotypes, had no prognostic value in these intensive protocols designed for adult patients up to the age of 60 years. © 2017 by The American Society of Hematology.

  5. EP300-ZNF384 fusion gene product up-regulates GATA3 gene expression and induces hematopoietic stem cell gene expression signature in B-cell precursor acute lymphoblastic leukemia cells.

    Science.gov (United States)

    Yaguchi, Akinori; Ishibashi, Takeshi; Terada, Kazuki; Ueno-Yokohata, Hitomi; Saito, Yuya; Fujimura, Junya; Shimizu, Toshiaki; Ohki, Kentaro; Manabe, Atsushi; Kiyokawa, Nobutaka

    2017-08-01

    ZNF384-related fusion genes are associated with a distinct subgroup of B-cell precursor acute lymphoblastic leukemias in childhood, with a frequency of approximately 3-4%. We previously identified a novel EP300-ZNF384 fusion gene. Patients with the ZNF384-related fusion gene exhibit a hematopoietic stem cell (HSC) gene expression signature and characteristic immunophenotype with negative or low expression of CD10 and aberrant expression of myeloid antigens, such as CD33 and CD13. However, the molecular basis of this pathogenesis remains completely unknown. In the present study, we examined the biological effects of EP300-ZNF384 expression induced by retrovirus-mediated gene transduction in an REH B-cell precursor acute lymphoblastic leukemia cell line, and observed the acquisition of the HSC gene expression signature and an up-regulation of GATA3 gene expression, as assessed by microarray analysis. In contrast, the gene expression profile induced by wild-type ZNF384 in REH cells was significantly different from that by EP300-ZNF384 expression. Together with the results of reporter assays, which revealed the enhancement of GATA3-promoter activity by EP300-ZNF384 expression, these findings suggest that EP300-ZNF384 mediates GATA3 gene expression and may be involved in the acquisition of the HSC gene expression signature and characteristic immunophenotype in B-cell precursor acute lymphoblastic leukemia cells.

  6. Focal adhesion kinase activation is necessary for stretch-induced alignment and enhanced differentiation of myogenic precursor cells

    DEFF Research Database (Denmark)

    Andersen, Jens Isak; Pennisi, Cristian Pablo; Fink, Trine

    2017-01-01

    Myogenic precursors sense and dynamically respond to mechanical stimulation through complex integrin-mediated mechanotransduction, in which focal adhesion kinase (FAK) is a fundamental intracellular signaling mediator. When skeletal myoblasts are exposed to uniaxial cyclic tensile strain (UCTS...

  7. Improved performance of CH3NH3PbBr3 perovskite solar cells utilizing PbI2 precursors

    Science.gov (United States)

    Yang, Yang; Zhang, Taiyang; Tian, Hongxiang; Zhao, Zhiguo; Qin, Xiaojun; Wu, Junbo

    2017-11-01

    High-quality CH3NH3PbBr3 films have been made utilizing the PbI2 precursor via a two-step sequential deposition method. The use of the PbI2 precursor has significantly improved the film quality. UV-Vis results show that the PbI2 precursor leads to moderately enhanced absorptions. XRD and SEM characterizations suggest that compact and uniform films with large grain sizes and high crystallinity can be obtained utilizing PbI2. The power conversion efficiency of the FTO/compact-TiO2/MAPbBr3/Spiro-OMeTAD/Ag device increased from 5.3% to 7.6% after changing the PbBr2 precursor to PbI2. The reaction between PbI2 and excess MABr generated MAPbBr3 through halide anion exchange.

  8. Concise review: preleukemic stem cells: molecular biology and clinical implications of the precursors to leukemia stem cells.

    Science.gov (United States)

    Pandolfi, Ashley; Barreyro, Laura; Steidl, Ulrich

    2013-02-01

    Recent experimental evidence has shown that acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS) arise from transformed immature hematopoietic cells following the accumulation of multiple stepwise genetic and epigenetic changes in hematopoietic stem cells and committed progenitors. The series of transforming events initially gives rise to preleukemic stem cells (pre-LSC), preceding the formation of fully transformed leukemia stem cells (LSC). Despite the established use of poly-chemotherapy, relapse continues to be the most common cause of death in AML and MDS. The therapeutic elimination of all LSC, as well as pre-LSC, which provide a silent reservoir for the re-formation of LSC, will be essential for achieving lasting cures. Conventional sequencing and next-generation genome sequencing have allowed us to describe many of the recurrent mutations in the bulk cell populations in AML and MDS, and recent work has also focused on identifying the initial molecular changes contributing to leukemogenesis. Here we review recent and ongoing advances in understanding the roles of pre-LSC, and the aberrations that lead to pre-LSC formation and subsequent LSC transformation.

  9. OTX2 exhibits cell-context-dependent effects on cellular and molecular properties of human embryonic neural precursors and medulloblastoma cells

    Directory of Open Access Journals (Sweden)

    Ravinder Kaur

    2015-10-01

    Full Text Available Medulloblastoma (MB is the most common malignant primary pediatric brain tumor and is currently divided into four subtypes based on different genomic alterations, gene expression profiles and response to treatment: WNT, Sonic Hedgehog (SHH, Group 3 and Group 4. This extensive heterogeneity has made it difficult to assess the functional relevance of genes to malignant progression. For example, expression of the transcription factor Orthodenticle homeobox2 (OTX2 is frequently dysregulated in multiple MB variants; however, its role may be subtype specific. We recently demonstrated that neural precursors derived from transformed human embryonic stem cells (trans-hENs, but not their normal counterparts (hENs, resemble Groups 3 and 4 MB in vitro and in vivo. Here, we tested the utility of this model system as a means of dissecting the role of OTX2 in MB using gain- and loss-of-function studies in hENs and trans-hENs, respectively. Parallel experiments with MB cells revealed that OTX2 exerts inhibitory effects on hEN and SHH MB cells by regulating growth, self-renewal and migration in vitro and tumor growth in vivo. This was accompanied by decreased expression of pluripotent genes, such as SOX2, and was supported by overexpression of SOX2 in OTX2+ SHH MB and hENs that resulted in significant rescue of self-renewal and cell migration. By contrast, OTX2 is oncogenic and promotes self-renewal of trans-hENs and Groups 3 and 4 MB independent of pluripotent gene expression. Our results demonstrate a novel role for OTX2 in self-renewal and migration of hENs and MB cells and reveal a cell-context-dependent link between OTX2 and pluripotent genes. Our study underscores the value of human embryonic stem cell derivatives as alternatives to cell lines and heterogeneous patient samples for investigating the contribution of key developmental regulators to MB progression.

  10. PPARγ inhibits inflammation and RANKL expression in epoxy resin-based sealer-induced osteoblast precursor cells E1 cells.

    Science.gov (United States)

    Kim, Tae-Gun; Lee, Young-Hee; Bhattari, Govinda; Lee, Nan-Hee; Lee, Kwang-Won; Yi, Ho-Keun; Yu, Mi-Kyung

    2013-01-01

    The AH26 of epoxy resin-based sealer is used widely owing to its excellent physical characteristics but it induces oxidative stress and cytotoxicity at the periapical tissues. AH26 exhibited cytotoxicity towards MC-3T3-E1 cells, which resulted in mitochondria-mediated apoptosis. Peroxisome proliferator-activated receptor (PPARγ) has an anti-inflammatory effect in several tissue and cells, but its action of AH26-related inflammation is not completely understood. The aim of this study is to investigate the anti-inflammatory and anti-osteoclastic mechanisms of PPARγ in AH26-induced MC-3T3 E1 cells. AH26 was prepared according to the manufacturer's instructions. The 1-day extraction sample, which was diluted by 30%, was tested in this experiment. Recombinant deficiency adenoviral PPARγ (Ad/PPARγ) was used to examine PPARγ over-expression in MC-3T3 E1 cells. AH26-induced reactive oxygen species (ROS) formation was analysed using 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA) with fluorescence-activated cell sorting (FACS), and the expression of receptor activator of nuclear factor-κB ligand (RANKL) and inflammatory molecules was determined by immunoblotting. The anti-inflammatory and anti-osteoclastic mechanisms of the PPARγ-involved signal pathway was examined by immunoblotting. The AH26 elutes induced inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), RANKL expression and ROS formation. In addition, the AH26 elutes suppressed the expression of PPARγ. However, the recovery of PPARγ expression with Ad/PPARγ resulted in the inhibition of iNOS, COX-2, RANKL and ROS formation despite the AH26 treatment in MC-3T3 E1 cells. The mechanism of PPARγ was confirmed by the blocking of nuclear factor kappa B (NF-κB) translocation to the nucleus after the suppression of ERK1/2, SAPK/JNK and AP-1 in AH26-induced MC-3T3 E1 cells. From this result, PPARγ acts to inhibit bone destruction in AH26-induced bone cells. Therefore, the anti-inflammatory and

  11. Thermo-radiosensitivity of the granulocyte and macrophage precursor cells of mice. I.-Development of the in vivo culture and effects induced by the hyperthermia; Termo-radiosensibilidad del precursor hematopoyetico que origina las series granulocitica y macrofaga de raton. I.- Desarrollo del cultivo in vivo y efectos producidos por la hipertermia

    Energy Technology Data Exchange (ETDEWEB)

    Bueren, J. A.; Nieto, M.

    1983-07-01

    The present report shows the agar diffusion chamber technique for culturing granulocyte- macrophage precursor cells, obtained from mice bone marrow. Diffusion chambers containing the bone marrow suspension are implanted intraperitoneally Into mice and constitute a compartment which avoids the migration of cells, but allows the transit of the mouse biological fluxes, necessary for the cellular proliferation. By means of this technique, we studied the lethal effects of the hyperthermia on the precursors and their capacity to repair sublethal damage. (Author) 129 refs.

  12. Skin-derived precursors from human subjects with Type 2 diabetes yield dysfunctional vascular smooth muscle cells.

    Science.gov (United States)

    Steinbach, Sarah K; Yau, Terrence M; Ouzounian, Maral; Abdel-Qadir, Husam; Chandy, Mark; Waddell, Thomas K; Husain, Mansoor

    2017-08-01

    Objective : Few methods enable molecular and cellular studies of vascular aging or Type 2 diabetes (T2D). Here, we report a new approach to studying human vascular smooth muscle cell (VSMC) pathophysiology by examining VSMCs differentiated from progenitors found in skin. Approach and results : Skin-derived precursors (SKPs) were cultured from biopsies ( N =164, ∼1 cm 2 ) taken from the edges of surgical incisions of older adults ( N =158; males 72%; mean age 62.7 ± 13 years) undergoing cardiothoracic surgery, and differentiated into VSMCs at high efficiency (>80% yield). The number of SKPs isolated from subjects with T2D was ∼50% lower than those without T2D (cells/g: 0.18 ± 0.03, N =58 versus 0.40 ± 0.05, N =100, P <0.05). Importantly, SKP-derived VSMCs from subjects with T2D had higher Fluo-5F-determined baseline cytosolic Ca 2+ concentrations (AU: 1,968 ± 160, N =7 versus 1,386 ± 170, N =13, P <0.05), and a trend toward greater Ca 2+ cycling responses to norepinephrine (NE) (AUC: 177,207 ± 24,669, N =7 versus 101,537 ± 15,881, N =20, P <0.08) despite a reduced frequency of Ca 2+ cycling (events s -1 cell -1 : 0.011 ± 0.004, N =8 versus 0.021 ± 0.003, N =19, P <0.05) than those without T2D. SKP-derived VSMCs from subjects with T2D also manifest enhanced sensitivity to phenylephrine (PE) in an impedance-based assay (EC 50 nM: 72.3 ± 63.6, N =5 versus 3,684 ± 3,122, N =9, P <0.05), and impaired wound closure in vitro (% closure: 21.9 ± 3.6, N =4 versus 67.0 ± 10.3, N =4, P <0.05). Compared with aortic- and saphenous vein-derived primary VSMCs, SKP-derived VSMCs are functionally distinct, but mirror defects of T2D also exhibited by primary VSMCs. Skin biopsies from older adults yield sufficient SKPs to differentiate VSMCs, which reveal abnormal phenotypes of T2D that survive differentiation and persist even after long-term normoglycemic culture. © 2017 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

  13. Large-scale expansion of human skin-derived precursor cells (hSKPs) in stirred suspension bioreactors.

    Science.gov (United States)

    Surrao, Denver C; Boon, Kathryn; Borys, Breanna; Sinha, Sarthak; Kumar, Ranjan; Biernaskie, Jeff; Kallos, Michael S

    2016-12-01

    Human skin-derived precursor cells (hSKPs) are multipotent adult stem cells found in the dermis of human skin. Incorporation of hSKPs into split-thickness skin grafts (STSGs), the current gold standard to treat severe burns or tissue resections, has been proposed as a treatment option to enhance skin wound healing and tissue function. For this approach to be clinically viable substantial quantities of hSKPs are required, which is the rate-limiting step, as only a few thousand hSKPs can be isolated from an autologous skin biopsy without causing donor site morbidity. In order to produce sufficient quantities of clinically viable cells, we have developed a bioprocess capable of expanding hSKPs as aggregates in stirred suspension bioreactors (SSBs). In this study, we found hSKPs from adult donors to expand significantly more (P < 0.05) at 60 rpm in SSBs than in static cultures. Furthermore, the utility of the SSBs, at 60 rpm is demonstrated by serial passaging of hSKPs from a small starting population, which can be isolated from an autologous skin biopsy without causing donor site morbidity. At 60 rpm, aggregates were markedly smaller and did not experience oxygen diffusional limitations, as seen in hSKPs cultured at 40 rpm. While hSKPs also grew at 80 rpm (0.74 Pa) and 100 rpm (1 Pa), they produced smaller aggregates due to high shear stress. The pH of the media in all the SSBs was closer to biological conditions and significantly different (P < 0.05) from static cultures, which recorded acidic pH conditions. The nutrient concentrations of the media in all the SSBs and static cultures did not drop below acceptable limits. Furthermore, there was no significant build-up of waste products to limit hSKP expansion in the SSBs. In addition, hSKP markers were maintained in the 60 rpm SSB as demonstrated by immunocytochemistry. This method of growing hSKPs in a batch culture at 60 rpm in a SSB represents an important first step in developing an

  14. Paclitaxel and CYC3, an aurora kinase A inhibitor, synergise in pancreatic cancer cells but not bone marrow precursor cells

    Science.gov (United States)

    Lin, Y; Richards, F M; Krippendorff, B-F; Bramhall, J L; Harrington, J A; Bapiro, T E; Robertson, A; Zheleva, D; Jodrell, D I

    2012-01-01

    Background: Amplification of aurora kinase A (AK-A) overrides the mitotic spindle assembly checkpoint, inducing resistance to taxanes. RNA interference targeting AK-A in human pancreatic cancer cell lines enhanced taxane chemosensitivity. In this study, a novel AK-A inhibitor, CYC3, was investigated in pancreatic cancer cell lines, in combination with paclitaxel. Methods: Western blot, flow cytometry and immunostaining were used to investigate the specificity of CYC3. Sulforhodamine B staining, time-lapse microscopy and colony-formation assays were employed to evaluate the cytotoxic effect of CYC3 and paclitaxel. Human colony-forming unit of granulocyte and macrophage (CFU-GM) cells were used to compare the effect in tumour and normal tissue. Results: CYC3 was shown to be a specific AK-A inhibitor. Three nanomolar paclitaxel (growth inhibition 50% (GI50) 3 nℳ in PANC-1, 5.1 nℳ in MIA PaCa-2) in combination with 1 μℳ CYC3 (GI50 1.1 μℳ in MIA PaCa2 and 2 μℳ in PANC-1) was synergistic in inhibiting pancreatic cell growth and causing mitotic arrest, achieving similar effects to 10-fold higher concentrations of paclitaxel (30 nℳ). In CFU-GM cells, the effect of the combination was simply additive, displaying significantly less myelotoxicity compared with high concentrations of paclitaxel (30 nℳ; 60–70% vs 100% inhibition). Conclusion: The combination of lower doses of paclitaxel and CYC3 merits further investigation with the potential for an improved therapeutic index in vivo. PMID:23037716

  15. Transplantation of ciliary neurotrophic factor-expressing adult oligodendrocyte precursor cells promotes remyelination and functional recovery after spinal cord injury.

    Science.gov (United States)

    Cao, Qilin; He, Qian; Wang, Yaping; Cheng, Xiaoxin; Howard, Russell M; Zhang, Yiping; DeVries, William H; Shields, Christopher B; Magnuson, David S K; Xu, Xiao-Ming; Kim, Dong H; Whittemore, Scott R

    2010-02-24

    Demyelination contributes to the dysfunction after traumatic spinal cord injury (SCI). We explored whether the combination of neurotrophic factors and transplantation of adult rat spinal cord oligodendrocyte precursor cells (OPCs) could enhance remyelination and functional recovery after SCI. Ciliary neurotrophic factor (CNTF) was the most effective neurotrophic factor to promote oligodendrocyte (OL) differentiation and survival of OPCs in vitro. OPCs were infected with retroviruses expressing enhanced green fluorescent protein (EGFP) or CNTF and transplanted into the contused adult thoracic spinal cord 9 d after injury. Seven weeks after transplantation, the grafted OPCs survived and integrated into the injured spinal cord. The survival of grafted CNTF-OPCs increased fourfold compared with EGFP-OPCs. The grafted OPCs differentiated into adenomatus polyposis coli (APC(+)) OLs, and CNTF significantly increased the percentage of APC(+) OLs from grafted OPCs. Immunofluorescent and immunoelectron microscopic analyses showed that the grafted OPCs formed central myelin sheaths around the axons in the injured spinal cord. The number of OL-remyelinated axons in ventrolateral funiculus (VLF) or lateral funiculus (LF) at the injured epicenter was significantly increased in animals that received CNTF-OPC grafts compared with all other groups. Importantly, 75% of rats receiving CNTF-OPC grafts recovered transcranial magnetic motor-evoked potential and magnetic interenlargement reflex responses, indicating that conduction through the demyelinated axons in VLF or LF, respectively, was partially restored. More importantly, recovery of hindlimb locomotor function was significantly enhanced in animals receiving grafts of CNTF-OPCs. Thus, combined treatment with OPC grafts expressing CNTF can enhance remyelination and facilitate functional recovery after traumatic SCI.

  16. Transplantation of CNTF-expressing adult oligodendrocyte precursor cells promotes remyelination and functional recovery after spinal cord injury

    Science.gov (United States)

    Cao, Qilin; He, Qian; Wang, Yaping; Cheng, Xiaoxin; Howard, Russell M.; Zhang, Yiping; DeVries, William H.; Shields, Christopher B.; Magnuson, David S.K.; Xu, Xiaoming; Kim, Dong H.; Whittemore, Scott R.

    2010-01-01

    Demyelination contributes to the dysfunction after traumatic spinal cord injury (SCI). We explored whether the combination of neurotrophic factors and transplantation of adult rat spinal cord oligodendrocyte precursor cells (OPCs) could enhance remyelination and functional recovery after SCI. Ciliary neurotrophic factor (CNTF) was the most effective neurotrophic factor to promote oligodendrocyte (OL) differentiation and survival of OPCs in vitro. OPCs were infected with retroviruses expressing EGFP or CNTF and transplanted into the contused adult thoracic spinal cord 9 days post-injury. Seven weeks after transplantation, the grafted OPCs survived and integrated into the injured spinal cord. The survival of grafted CNTF-OPCs increased 4-fold compared to EGFP-OPCs. The grafted OPCs differentiated into adenomatus polyposis coli (APC+) OLs and CNTF significantly increased the percentage of APC+ OLs from grafted OPCs. Immunofluoresent and immuno-electron microscopic analyses showed that the grafted OPCs formed central myelin sheaths around the axons in the injured spinal cord. The number of OL-remyelinated axons in ventrolateral funiculus (VLF) or lateral funiculus (LF) at the injured epiecenter was significantly increased in animals that received CNTF-OPC grafts compared to all other groups. Importantly, 75% of rats receiving CNTF-OPC grafts recovered transcranial magnetic motor-evoked potential (tcMMEP) and magnetic inter-englargement reflex (MIER) responses, indicating that conduction through the demyelinated axons in VLF or LF, respectively, was partially restored. More importantly, recovery of hindlimb locomotor function was significantly enhanced in animals receiving grafts of CNTF-OPCs. Thus, combined treatment with OPC grafts expressing CNTF can enhance remyelination and facilitate functional recovery after traumatic SCI. PMID:20181596

  17. Intrathecal Transplantation of Embryonic Stem Cell-Derived Spinal GABAergic Neural Precursor Cells Attenuates Neuropathic Pain in a Spinal Cord Injury Rat Model.

    Science.gov (United States)

    Hwang, Insik; Hahm, Suk-Chan; Choi, Kyung-Ah; Park, Sung-Ho; Jeong, Hyesun; Yea, Ji-Hye; Kim, Junesun; Hong, Sunghoi

    2016-01-01

    Neuropathic pain following spinal cord injury (SCI) is a devastating disease characterized by spontaneous pain such as hyperalgesia and allodynia. In this study, we investigated the therapeutic potential of ESC-derived spinal GABAergic neurons to treat neuropathic pain in a SCI rat model. Mouse embryonic stem cell-derived neural precursor cells (mESC-NPCs) were cultured in media supplemented with sonic hedgehog (SHH) and retinoic acid (RA) and efficiently differentiated into GABAergic neurons. Interestingly, low doses of SHH and RA induced MGE-like progenitors, which expressed low levels of DARPP32 and Nkx2.1 and high levels of Irx3 and Pax6. These cells subsequently generated the majority of the DARPP32(-) GABAergic neurons after in vitro differentiation. The spinal mESC-NPCs were intrathecally transplanted into the lesion area of the spinal cord around T10-T11 at 21 days after SCI. The engrafted spinal GABAergic neurons remarkably increased both the paw withdrawal threshold (PWT) below the level of the lesion and the vocalization threshold (VT) to the level of the lesion (T12, T11, and T10 vertebrae), which indicates attenuation of chronic neuropathic pain by the spinal GABAergic neurons. The transplanted cells were positive for GABA antibody staining in the injured region, and cells migrated to the injured spinal site and survived for more than 7 weeks in L4-L5. The mESC-NPC-derived spinal GABAergic neurons dramatically attenuated the chronic neuropathic pain following SCI, suggesting that the spinal GABAergic mESC-NPCs cultured with low doses of SHH and RA could be alternative cell sources for treatment of SCI neuropathic pain by stem cell-based therapies.

  18. Role of receptors to fibroblast growth factor (FGF) on mesenchymal precursor cells in the realization of regenerative effects of alkaloid songorine.

    Science.gov (United States)

    Zyuz'kov, G N; Chaikovskii, A V; Ligacheva, A A; Zhdanov, V V; Udut, E V; Danilets, M G; Miroshnichenko, L A; Simanina, E V; Suslov, N I; Losev, E A; Trofimova, E S; Povet'eva, T N; Nesterova, Yu V; Fomina, T I; Minakova, M Yu; Dygai, A M

    2014-05-01

    We studied the mechanisms of regenerative (wound healing) effects of songorine associated with functional activation of mesenchymal progenitor cells. The key role of FGF receptors on these progenitor cells in the stimulation of realization of their growth potential under the effect of the alkaloid was demonstrated. Under in vitro conditions, the antibodies to FGF receptor abolished the songorine-induced increase in the number of fibroblast colony-forming units in bone marrow cell culture. The intensity of differentiation of mesenchymal precursors remained unchanged.

  19. Neuroprotective Properties of Endocannabinoids N-Arachidonoyl Dopamine and N-Docosahexaenoyl Dopamine Examined in Neuronal Precursors Derived from Human Pluripotent Stem Cells.

    Science.gov (United States)

    Novosadova, E V; Arsenyeva, E L; Manuilova, E S; Khaspekov, L G; Bobrov, M Yu; Bezuglov, V V; Illarioshkin, S N; Grivennikov, I A

    2017-11-01

    Neuroprotective properties of endocannabinoids N-arachidonoyl dopamine (NADA) and N-docosahexaenoyl dopamine (DHDA) were examined in neuronal precursor cells differentiated from human induced pluripotent stem cells and subjected to oxidative stress. Both compounds exerted neuroprotective activity, which was enhanced by elevating the concentration of the endocannabinoids within the 0.1-10 µM range. However, both agents at 10 µM concentration showed a marked toxic effect resulting in death of ~30% of the cells. Finally, antagonists of cannabinoid receptors as well as the receptor of the TRPV1 endovanilloid system did not hamper the neuroprotective effects of these endocannabinoids.

  20. Facile synthesis of Cu2ZnSnS4 absorber layer for thin film solar cells using a highly stable precursor solution

    Science.gov (United States)

    Dhanasekar, M.; Bhat, S. Venkataprasad

    2017-10-01

    In search of simpler, environment friendly, scalable method to make device quality Cu2ZnSnS4 semiconductor thinfilms for solar cell applications, we have developed a solution based technique based on a highly stable precursor solution. A clear transparent precursor solution, stable for more than a year was prepared using a novel combination of the sulfur source and the solvent. The absorber film on Mo coated glass substrate was formed by dip-coating and drying in open air, followed by annealing in inert atmosphere. Further, we have fabricated and demonstrated a simple solar cell, combining this method with vacuum-free laminated conductive tape as the top electrode, having the device structure of glass/Mo/CZTS/CdS/Al.

  1. THE AMYLOID PRECURSOR PROTEIN-FRAGMENT HIS-657-LYS-676 INHIBITS NORADRENALINE-INDUCED AND ENKEPHALINE-INDUCED SUPPRESSION OF VOLTAGE-SENSITIVE CALCIUM CURRENTS IN NG108-15 HYBRID-CELLS

    NARCIS (Netherlands)

    BODDEKE, HWGM; MEIGEL, [No Value; SWOBODA, R; BOEIJINGA, PH

    1994-01-01

    We have investigated the effects of the C-terminal amyloid precursor protein fragment His 657-Lys 676 upon calcium currents in NG108-15 neuroblastoma x glioma hybrid cells. The amyloid precursor protein fragment His 657-Lys 676 (1-10 mu M) did not affect calcium currents pel se, but clearly blocked

  2. Remyelination Is Correlated with Regulatory T Cell Induction Following Human Embryoid Body-Derived Neural Precursor Cell Transplantation in a Viral Model of Multiple Sclerosis.

    Directory of Open Access Journals (Sweden)

    Warren C Plaisted

    Full Text Available We have recently described sustained clinical recovery associated with dampened neuroinflammation and remyelination following transplantation of neural precursor cells (NPCs derived from human embryonic stem cells (hESCs in a viral model of the human demyelinating disease multiple sclerosis. The hNPCs used in that study were derived by a novel direct differentiation method (direct differentiation, DD-NPCs that resulted in a unique gene expression pattern when compared to hNPCs derived by conventional methods. Since the therapeutic potential of human NPCs may differ greatly depending on the method of derivation and culture, we wanted to determine whether NPCs differentiated using conventional methods would be similarly effective in improving clinical outcome under neuroinflammatory demyelinating conditions. For the current study, we utilized hNPCs differentiated from a human induced pluripotent cell line via an embryoid body intermediate stage (EB-NPCs. Intraspinal transplantation of EB-NPCs into mice infected with the neurotropic JHM strain of mouse hepatitis virus (JHMV resulted in decreased accumulation of CD4+ T cells in the central nervous system that was concomitant with reduced demyelination at the site of injection. Dampened neuroinflammation and remyelination was correlated with a transient increase in CD4+FOXP3+ regulatory T cells (Tregs concentrated within the peripheral lymphatics. However, compared to our earlier study, pathological improvements were modest and did not result in significant clinical recovery. We conclude that the genetic signature of NPCs is critical to their effectiveness in this model of viral-induced neurologic disease. These comparisons will be useful for understanding what factors are critical for the sustained clinical improvement.

  3. FLT3 mutations in early T-cell precursor ALL characterize a stem cell like leukemia and imply the clinical use of tyrosine kinase inhibitors.

    Directory of Open Access Journals (Sweden)

    Martin Neumann

    Full Text Available Early T-cell precursor acute lymphoblastic leukemia (ETP-ALL has been identified as high-risk subgroup of acute T-lymphoblastic leukemia (T-ALL with a high rate of FLT3-mutations in adults. To unravel the underlying pathomechanisms and the clinical course we assessed molecular alterations and clinical characteristics in a large cohort of ETP-ALL (n = 68 in comparison to non-ETP T-ALL adult patients. Interestingly, we found a high rate of FLT3-mutations in ETP-ALL samples (n = 24, 35%. Furthermore, FLT3 mutated ETP-ALL was characterized by a specific immunophenotype (CD2+/CD5-/CD13+/CD33-, a distinct gene expression pattern (aberrant expression of IGFBP7, WT1, GATA3 and mutational status (absence of NOTCH1 mutations and a low frequency, 21%, of clonal TCR rearrangements. The observed low GATA3 expression and high WT1 expression in combination with lack of NOTCH1 mutations and a low rate of TCR rearrangements point to a leukemic transformation at the pluripotent prothymocyte stage in FLT3 mutated ETP-ALL. The clinical outcome in ETP-ALL patients was poor, but encouraging in those patients with allogeneic stem cell transplantation (3-year OS: 74%. To further explore the efficacy of targeted therapies, we demonstrate that T-ALL cell lines transfected with FLT3 expression constructs were particularly sensitive to tyrosine kinase inhibitors. In conclusion, FLT3 mutated ETP-ALL defines a molecular distinct stem cell like leukemic subtype. These data warrant clinical studies with the implementation of FLT3 inhibitors in addition to early allogeneic stem cell transplantation for this high risk subgroup.

  4. ZNF384-related fusion genes define a subgroup of childhood B-cell precursor acute lymphoblastic leukemia with a characteristic immunotype.

    Science.gov (United States)

    Hirabayashi, Shinsuke; Ohki, Kentaro; Nakabayashi, Kazuhiko; Ichikawa, Hitoshi; Momozawa, Yukihide; Okamura, Kohji; Yaguchi, Akinori; Terada, Kazuki; Saito, Yuya; Yoshimi, Ai; Ogata-Kawata, Hiroko; Sakamoto, Hiromi; Kato, Motohiro; Fujimura, Junya; Hino, Moeko; Kinoshita, Akitoshi; Kakuda, Harumi; Kurosawa, Hidemitsu; Kato, Keisuke; Kajiwara, Ryosuke; Moriwaki, Koichi; Morimoto, Tsuyoshi; Nakamura, Kozue; Noguchi, Yasushi; Osumi, Tomoo; Sakashita, Kazuo; Takita, Junko; Yuza, Yuki; Matsuda, Koich; Yoshida, Teruhiko; Matsumoto, Kenji; Hata, Kenichiro; Kubo, Michiaki; Matsubara, Yoichi; Fukushima, Takashi; Koh, Katsuyoshi; Manabe, Atsushi; Ohara, Akira; Kiyokawa, Nobutaka

    2017-01-01

    Fusion genes involving ZNF384 have recently been identified in B-cell precursor acute lymphoblastic leukemia, and 7 fusion partners have been reported. We further characterized this type of fusion gene by whole transcriptome sequencing and/or polymerase chain reaction. In addition to previously reported genes, we identified BMP2K as a novel fusion partner for ZNF384 Including the EP300-ZNF384 that we reported recently, the total frequency of ZNF384-related fusion genes was 4.1% in 291 B-cell precursor acute lymphoblastic leukemia patients enrolled in a single clinical trial, and TCF3-ZNF384 was the most recurrent, with a frequency of 2.4%. The characteristic immunophenotype of weak CD10 and aberrant CD13 and/or CD33 expression was revealed to be a common feature of the leukemic cells harboring ZNF384-related fusion genes. The signature gene expression profile in TCF3-ZNF384-positive patients was enriched in hematopoietic stem cell features and related to that of EP300-ZNF384-positive patients, but was significantly distinct from that of TCF3-PBX1-positive and ZNF384-fusion-negative patients. However, clinical features of TCF3-ZNF384-positive patients are markedly different from those of EP300-ZNF384-positive patients, exhibiting higher cell counts and a younger age at presentation. TCF3-ZNF384-positive patients revealed a significantly poorer steroid response and a higher frequency of relapse, and the additional activating mutations in RAS signaling pathway genes were detected by whole exome analysis in some of the cases. Our observations indicate that ZNF384-related fusion genes consist of a distinct subgroup of B-cell precursor acute lymphoblastic leukemia with a characteristic immunophenotype, while the clinical features depend on the functional properties of individual fusion partners. Copyright© Ferrata Storti Foundation.

  5. Secretion of a precursor form of lysosomal alpha-glucosidase from the brush border of human kidney proximal tubule cells

    NARCIS (Netherlands)

    Klumperman, J.; Oude Elferink, R.P.; Fransen, J.A.; Ginsel, L.A.; Tager, J.M.

    1989-01-01

    We have shown previously (R.P.J. Oude Elferink, E.M. Brouwer-Kelder, I. Surya, A. Strijland, M. Kroos, A.J.J. Reuser, J.M. Tager, Eur. J. Biochem. 139, 489-495 (1984)) that human urine contains considerable amounts of a precursor form of lysosomal alpha-glucosidase (about 50% of the total

  6. Muscle precursor cells in the developing limbs of two isopods (Crustacea, Peracarida): an immunohistochemical study using a novel monoclonal antibody against myosin heavy chain

    Science.gov (United States)

    Kreissl, S.; Uber, A.

    2008-01-01

    In the hot debate on arthropod relationships, Crustaceans and the morphology of their appendages play a pivotal role. To gain new insights into how arthropod appendages evolved, developmental biologists recently have begun to examine the expression and function of Drosophila appendage genes in Crustaceans. However, cellular aspects of Crustacean limb development such as myogenesis are poorly understood in Crustaceans so that the interpretative context in which to analyse gene functions is still fragmentary. The goal of the present project was to analyse muscle development in Crustacean appendages, and to that end, monoclonal antibodies against arthropod muscle proteins were generated. One of these antibodies recognises certain isoforms of myosin heavy chain and strongly binds to muscle precursor cells in malacostracan Crustacea. We used this antibody to study myogenesis in two isopods, Porcellio scaber and Idotea balthica (Crustacea, Malacostraca, Peracarida), by immunohistochemistry. In these animals, muscles in the limbs originate from single muscle precursor cells, which subsequently grow to form multinucleated muscle precursors. The pattern of primordial muscles in the thoracic limbs was mapped, and results compared to muscle development in other Crustaceans and in insects. Electronic supplementary material The online version of this article (doi:10.1007/s00427-008-0216-1) contains supplementary material, which is available to authorized users. PMID:18443823

  7. Lead decreases cell survival, proliferation, and neuronal differentiation of primary cultured adult neural precursor cells through activation of the JNK and p38 MAP kinases

    Science.gov (United States)

    Engstrom, Anna; Wang, Hao; Xia, Zhengui

    2015-01-01

    Adult hippocampal neurogenesis is the process whereby adult neural precursor cells (aNPCs) in the subgranular zone (SGZ) of the dentate gyrus (DG) generate adult-born, functional neurons in the hippocampus. This process is modulated by various extracellular and intracellular stimuli, and the adult-born neurons have been implicated in hippocampus-dependent learning and memory. However, studies on how neurotoxic agents affect this process and the underlying mechanisms are limited. The goal of this study was to determine whether lead, a heavy metal, directly impairs critical processes in adult neurogenesis and to characterize the underlying signaling pathways using primary cultured SGZ-aNPCs isolated from adult mice. We report here that lead significantly increases apoptosis and inhibits proliferation in SGZ-aNPCs. In addition, lead significantly impairs spontaneous neuronal differentiation and maturation. Furthermore, we found that activation of the c-Jun NH2-terminal kinase (JNK) and p38 mitogen activated protein (MAP) kinase signaling pathways are important for lead cytotoxicity. Our data suggest that lead can directly act on adult neural stem cells and impair critical processes in adult hippocampal neurogenesis, which may contribute to its neurotoxicity and adverse effects on cognition in adults. PMID:25967738

  8. Thermo-radiosensitivity of the granulocyte and macrophage precursor cells of mice. I I . - X- irradiation effects and influence of hyperthermia on the radiosensitivity; Termo-radiosensibilidad del precursor hematopoyetico que origina las series granulocitica y macrofaga de raton. II. - Efectos producidos por la radiacion X e influencia de la hipertermia sobre la radiosensibilidad celular

    Energy Technology Data Exchange (ETDEWEB)

    Bueren, J. A.; Nieto, M.

    1983-07-01

    The effects of the X-irradiation on the viability of the granulocyte-macrophage precursors, has been determined by means of the agar diffusion chamber culture technique. The results show the high radiosensitivity of these cells, with survival parameter similar to those previously reported in the literature about different granulocyte-macrophage precursors. When a hyperthermic treatment is performed prior to the X-irradiation, a radiosensitization phenomenon is observed due to the synergism existent between hyperthermia and X rays on the lethality of the precursors. (Authors) 37 refs.

  9. Erythroblast cell expansion as a marker for disease severity in β ...

    African Journals Online (AJOL)

    Yomi

    2012-01-05

    Jan 5, 2012 ... differentiation in culture. The cell surface antigen CD34 or hemopoietic progenitor cell antigen 1 (HPCA1), is expressed selectively on early hematopoietic stem cells and this expression can be used to isolate these cells using specific monoclonal antibodies directed against this antigen (Giarratana et al., ...

  10. Gum hypertrophy--an unusual presenting feature in a case of precursor T-cell acute lymphoblastic leukemia/ Dis eti hipertrofisi ile giden bir prekursor T hucreli akut lenfoblastik losemi olgusu

    National Research Council Canada - National Science Library

    Premalata, Chennagiri Srinivasamurthy; Madhumathi, Davanam Satyanarayana; Lakshmidevi, Visweswraiah; Pradeep, Rudramurthy; Appaji, Lingappa; Mukherjee, Geetashree

    2008-01-01

    ... and the central nervous system. We present a rare case of precursor T-cell acute lymphoblastic leukemia/lymphoma with initial oral manifestation, presenting with the unusual features of gum hypertrophy and involvement of upper jaw...

  11. Low NKp30, NKp46 and NKG2D expression and reduced cytotoxic activity on NK cells in cervical cancer and precursor lesions

    Directory of Open Access Journals (Sweden)

    Bravo-Cuellar Alejandro

    2009-06-01

    Full Text Available Abstract Background Persistent high risk HPV infection can lead to cervical cancer, the second most common malignant tumor in women worldwide. NK cells play a crucial role against tumors and virus-infected cells through a fine balance between activating and inhibitory receptors. Expression of triggering receptors NKp30, NKp44, NKp46 and NKG2D on NK cells correlates with cytolytic activity against tumor cells, but these receptors have not been studied in cervical cancer and precursor lesions. The aim of the present work was to study NKp30, NKp46, NKG2D, NKp80 and 2B4 expression in NK cells from patients with cervical cancer and precursor lesions, in the context of HPV infection. Methods NKp30, NKp46, NKG2D, NKp80 and 2B4 expression was analyzed by flow cytometry on NK cells from 59 patients with cervical cancer and squamous intraepithelial lesions. NK cell cytotoxicity was evaluated in a 4 hour CFSE/7-AAD flow cytometry assay. HPV types were identified by PCR assays. Results We report here for the first time that NK cell-activating receptors NKp30 and NKp46 are significantly down-regulated in cervical cancer and high grade squamous intraepithelial lesion (HGSIL patients. NCRs down-regulation correlated with low cytolytic activity, HPV-16 infection and clinical stage. NKG2D was also down-regulated in cervical cancer patients. Conclusion Our results suggest that NKp30, NKp46 and NKG2D down-regulation represent an evasion mechanism associated to low NK cell activity, HPV-16 infection and cervical cancer progression.

  12. Substituted 2,1,3-Benzothiadiazole- And Thiophene-Based Polymers for Solar Cells - Introducing a New Thermocleavable Precursor

    DEFF Research Database (Denmark)

    Petersen, Martin Helgesen; Gevorgyan, Suren; Krebs, Frederik C

    2009-01-01

    a reduced band gap in the range of 1.69−1.75 eV and were explored in polymer photovoltaic devices as mixtures with the soluble fullerene PCBM. High open circuit voltages of up to 0.93 V and power conversion efficiencies (PCE) of up to 2.22% was observed for materials without the thermally labile groups...... performance than for the soluble precursor polymers; however, we found processing conditions that lead to a higher performance for the thermocleaved product, where open circuit voltages of up to 0.9 V could be obtained with power conversion efficiencies of up to 0.42%, representing a doubling as compared...... to the soluble precursor polymer. Copyright © 2009 American Chemical Society...

  13. Atlantic salmon (Salmo salar) muscle precursor cells differentiate into osteoblasts in vitro: polyunsaturated fatty acids and hyperthermia influence gene expression and differentiation.

    Science.gov (United States)

    Ytteborg, Elisabeth; Vegusdal, Anne; Witten, P Eckhard; Berge, Gerd Marit; Takle, Harald; Østbye, Tone-Kari; Ruyter, Bente

    2010-02-01

    The formation and mineralisation of bone are two critical processes in fast-growing Atlantic salmon (Salmo salar). The mechanisms of these processes, however, have not been described in detail. Thus, in vitro systems that allow the study of factors that influence bone formation in farmed Atlantic salmon are highly warranted. We describe here a method by which unspecialized primary cells from salmon white muscle can differentiate to osteoblasts in vitro. We have subsequently used the differentiated cells as a model system to study the effects of two factors that influence bone formation in Atlantic salmon under commercial farming conditions, namely polyunsaturated fatty acids, PUFAs, and temperature. Muscle precursor cells changed their morphology from triangular or spindle-shaped cells to polygonal or cubical cells after 3 weeks in osteogenic medium. In addition, gene expression studies showed that marker genes for osteoblastogenesis; alp, col1a1, osteocalcin, bmp2 and bmp4 increased after 3 weeks of incubation in osteogenic media showing that these cells have differentiated to osteoblasts at this stage. Adding CLA or DHA to the osteoblast media resulted in a reduced PGE(2) production and increased expression of osteocalcin. Further, temperature studies showed that differentiating osteoblasts are highly sensitive to increased incubation temperature at early stages of differentiation. Our studies show that unspecialized precursor cells isolated from salmon muscle tissue can be caused to differentiate to osteoblasts in vitro. Furthermore, this model system appears to be suitable for the study of osteoblast biology in vitro. 2009 Elsevier B.V. All rights reserved.

  14. Cu2ZnSnSe4 Thin Film Solar Cell with Depth Gradient Composition Prepared by Selenization of Sputtered Novel Precursors.

    Science.gov (United States)

    Lai, Fang-I; Yang, Jui-Fu; Chen, Wei-Chun; Kuo, Shou-Yi

    2017-11-22

    In this study, we proposed a new method for the synthesis of the target material used in a two stage process for preparation of a high quality CZTSe thin film. The target material consisting of a mixture of CuxSe and ZnxSn1-x alloy was synthesized, providing a quality CZTSe precursor layer for highly efficient CZTSe thin film solar cells. The CZTSe thin film can be obtained by annealing the precursor layers through a 30 min selenization process under a selenium atmosphere at 550 °C. The CZTSe thin films prepared by using the new precursor thin film were investigated and characterized using X-ray diffraction, Raman scattering, and photoluminescence spectroscopy. It was found that diffusion of Sn occurred and formed the CTSe phase and CuxSe phase in the resultant CZTSe thin film. By selective area electron diffraction transmission electron microscopy images, the crystallinity of the CZTSe thin film was verified to be single crystal. By secondary ion mass spectroscopy measurements, it was confirmed that a double-gradient band gap profile across the CZTSe absorber layer was successfully achieved. The CZTSe solar cell with the CZTSe absorber layer consisting of the precursor stack exhibited a high efficiency of 5.46%, high short circuit current (JSC) of 37.47 mA/cm2, open circuit voltage (VOC) of 0.31 V, and fill factor (F.F.) of 47%, at a device area of 0.28 cm2. No crossover of the light and dark current-voltage (I-V) curves of the CZTSe solar cell was observed, and also, no red kink was observed under red light illumination, indicating a low defect concentration in the CZTSe absorber layer. Shunt leakage current with a characteristic metal/CZTSe/metal leakage current model was observed by temperature-dependent I-V curves, which led to the discovery of metal incursion through the CdS buffer layer on the CZTSe absorber layer. This leakage current, also known as space charge-limited current, grew larger as the measurement temperature increased and completely

  15. Viability, differentiation capacity, and detectability of super-paramagnetic iron oxide-labeled muscle precursor cells for magnetic-resonance imaging.

    Science.gov (United States)

    Azzabi, Fahd; Rottmar, Markus; Jovaisaite, Virginija; Rudin, Markus; Sulser, Tullio; Boss, Andreas; Eberli, Daniel

    2015-02-01

    Cell therapies are a promising approach for the treatment of a variety of human conditions including stress urinary incontinence, but their success greatly depends on the biodistribution, migration, survival, and differentiation of the transplanted cells. Noninvasive in vivo cell tracking therefore presents an important aspect for translation of such a procedure into the clinics. Upon labeling with superparamagnetic iron oxide (SPIO) nanoparticles, cells can be tracked by magnetic resonance imaging (MRI), but possible adverse effect of the labeling have to be considered when labeling stem cells with SPIOs. In this study, human muscle precursor cells (hMPC) were labeled with increasing concentrations of SPIO nanoparticles (100-1600 μg/mL) and cell viability and differentiation capacity upon labeling was assessed in vitro. While a linear dependence between cell viability and nanoparticle concentration could be observed, differentiation capacity was not affected by the presence of SPIOs. Using a nude mouse model, a concentration (400 μg/mL) could be defined that allows reliable detection of hMPCs by MRI but does not influence myogenic in vivo differentiation to mature and functional muscle tissue. This suggests that such an approach can be safely used in a clinical setting to track muscle regeneration in patients undergoing cell therapy without negative effects on the functionality of the bioengineered muscle.

  16. Expansion of revertant fibers in dystrophic mdx muscles reflects activity of muscle precursor cells and serves as an index of muscle regeneration.

    Science.gov (United States)

    Yokota, Toshifumi; Lu, Qi-Long; Morgan, Jennifer E; Davies, Kay E; Fisher, Rosie; Takeda, Shin'ichi; Partridge, Terence A

    2006-07-01

    Duchenne muscular dystrophy and the mdx mouse myopathies reflect a lack of dystrophin in muscles. However, both contain sporadic clusters of revertant fibers (RFs) that express dystrophin. RF clusters expand in size with age in mdx mice. To test the hypothesis that the expansion of clusters is achieved through the process of muscle degeneration and regeneration, we analyzed muscles of mdx mice in which degeneration and regeneration were inhibited by the expression of micro-dystrophins or utrophin transgenes. Postnatal RF expansion was diminished in direct correlation to the protective effect of the transgene expression. Similarly, expansion of RFs was inhibited when muscle regeneration was blocked by irradiation. However, in irradiated muscles, irradiation-tolerant quiescent muscle precursor cells reactivated by notexin effectively restored RF expansion. Our observations demonstrate that revertant events occur initially within a subset of muscle precursor cells. The proliferation of these cells, as part of the regeneration process, leads to the expansion of RF clusters within degenerating muscles. This expansion of revertant clusters depicts the cumulative history of regeneration, thus providing a useful index for functional evaluation of therapies that counteract muscle degeneration.

  17. CZTS absorber layer for thin film solar cells from electrodeposited metallic stacked precursors (Zn/Cu-Sn)

    Energy Technology Data Exchange (ETDEWEB)

    Khalil, M.I., E-mail: mdibrahim.khalil@polimi.it [Dipartimento di Chimica, Materiali e Ing. Chimica “Giulio Natta”, Politecnico di Milano, Via Mancinelli 7, 20131 Milano (Italy); Atici, O. [Dipartimento di Chimica, Materiali e Ing. Chimica “Giulio Natta”, Politecnico di Milano, Via Mancinelli 7, 20131 Milano (Italy); Lucotti, A. [Dipartimento di Chimica, Materiali e Ing. Chimica “Giulio Natta”, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano (Italy); Binetti, S.; Le Donne, A. [Department of Materials Science and Solar Energy Research Centre (MIB-SOLAR), University of Milano- Bicocca, Via Cozzi 53, 20125 Milano (Italy); Magagnin, L., E-mail: luca.magagnin@polimi.it [Dipartimento di Chimica, Materiali e Ing. Chimica “Giulio Natta”, Politecnico di Milano, Via Mancinelli 7, 20131 Milano (Italy)

    2016-08-30

    Highlights: • CZTS absorber layer was fabricated by electrodeposition—annealing route from stacked bilayer precursor (Zn/Cu-Sn). • Different characterization techniques have ensured the well formed Kesterite CZTS along the film thickness also. • Two different excitation wavelengths of laser lines (514.5 and 785 nm) have been used for the Raman characterization of the films. • No significant Sn loss is observed in CZTS films after the sulfurization of the stacked bilayer precursors. • Photoluminescence spectroscopy reveals the PL peak of CZTS at 1.15 eV at low temperature (15 K). - Abstract: In the present work, Kesterite-Cu{sub 2}ZnSnS{sub 4} (CZTS) thin films were successfully synthesized from stacked bilayer precursor (Zn/Cu-Sn) through electrodeposition-annealing route. Adherent and homogeneous Cu-poor, Zn-rich stacked metal Cu-Zn-Sn precursors with different compositions were sequentially electrodeposited, in the order of Zn/Cu-Sn onto Mo foil substrates. Subsequently, stacked layers were soft annealed at 350 °C for 20 min in flowing N{sub 2} atmosphere in order to improve intermixing of the elements. Then, sulfurization was completed at 585 °C for 15 min in elemental sulfur environment in a quartz tube furnace with N{sub 2} atmosphere. Morphological, compositional and structural properties of the films were investigated using SEM, EDS and XRD methods. Raman spectroscopy with two different excitation lines (514.5 and 785 nm), has been carried out on the sulfurized films in order to fully characterize the CZTS phase. Higher excitation wavelength showed more secondary phases, but with low intensities. Glow discharge optical emission spectroscopy (GDOES) has also been performed on films showing well formed Kesterite CZTS along the film thickness as compositions of the elements do not change along the thickness. In order to investigate the electronic structure of the CZTS, Photoluminescence (PL) spectroscopy has been carried out on the films, whose

  18. Preparation of thin films, with base to precursor materials of type Cu-In-Se elaborated by electrodeposition for the solar cells elaboration; Preparacion de peliculas delgadas, con base a materiales precursores del tipo Cu-In-Se, elaboradas por electrodeposito para la elaboracion de celdas solares

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, A.M. [Centro de Investigaciones en Energia, Universidad Nacional Autonoma de Mexico. Av. Xochicalco s/n. 62580 Temixco, Morelos (Mexico)

    1999-11-01

    Thin films of chalcogenide compounds are promising because they have excellent optoelectronic characteristics to be applied in solar cells. In particular, CuInSe{sub 2} and Cd Te thin films have shown high solar to electrical conversion efficiency. However, this efficiency is limited by the method of preparation, in this case, physical vapor deposition techniques are used. In order to increase the area of deposition t is necessary to use chemical methods, for example, electrodeposition technique. In this paper, the preparation of Cu-In-Se precursors thin films by electrochemical method is reported. These precursors were used to build solar cells with 7.9 % of efficiency. (Author)

  19. Brain fatty acid binding protein (Fabp7 is diurnally regulated in astrocytes and hippocampal granule cell precursors in adult rodent brain.

    Directory of Open Access Journals (Sweden)

    Jason R Gerstner

    Full Text Available Brain fatty acid binding protein (Fabp7, which is important in early nervous system development, is expressed in astrocytes and neuronal cell precursors in mature brain. We report here that levels of Fabp7 mRNA in adult murine brain change over a 24 hour period. Unlike Fabp5, a fatty acid binding protein that is expressed widely in various cell types within brain, RNA analysis revealed that Fabp7 mRNA levels were elevated during the light period and lower during dark in brain regions involved in sleep and activity mechanisms. This pattern of Fabp7 mRNA expression was confirmed using in situ hybridization and found to occur throughout the entire brain. Changes in the intracellular distribution of Fabp7 mRNA were also evident over a 24 hour period. Diurnal changes in Fabp7, however, were not found in postnatal day 6 brain, when astrocytes are not yet mature. In contrast, granule cell precursors of the subgranular zone of adult hippocampus did undergo diurnal changes in Fabp7 expression. These changes paralleled oscillations in Fabp7 mRNA throughout the brain suggesting that cell-coordinated signals likely control brain-wide Fabp7 mRNA expression. Immunoblots revealed that Fabp7 protein levels also underwent diurnal changes in abundance, with peak levels occurring in the dark period. Of clock or clock-regulated genes, the synchronized, global cycling pattern of Fabp7 expression is unique and implicates glial cells in the response or modulation of activity and/or circadian rhythms.

  20. EphA4 Regulates the Balance between Self-Renewal and Differentiation of Radial Glial Cells and Intermediate Neuronal Precursors in Cooperation with FGF Signaling.

    Directory of Open Access Journals (Sweden)

    Qingfa Chen

    Full Text Available In mouse cerebral corticogenesis, neurons are generated from radial glial cells (RGCs or from their immediate progeny, intermediate neuronal precursors (INPs. The balance between self-renewal of these neuronal precursors and specification of cell fate is critical for proper cortical development, but the signaling mechanisms that regulate this progression are poorly understood. EphA4, a member of the receptor tyrosine kinase superfamily, is expressed in RGCs during embryogenesis. To illuminate the function of EphA4 in RGC cell fate determination during early corticogenesis, we deleted Epha4 in cortical cells at E11.5 or E13.5. Loss of EphA4 at both stages led to precocious in vivo RGC differentiation toward neurogenesis. Cortical cells isolated at E14.5 and E15.5 from both deletion mutants showed reduced capacity for neurosphere formation with greater differentiation toward neurons. They also exhibited lower phosphorylation of ERK and FRS2α in the presence of FGF. The size of the cerebral cortex at P0 was smaller than that of controls when Epha4 was deleted at E11.5 but not when it was deleted at E13.5, although the cortical layers were formed normally in both mutants. The number of PAX6-positive RGCs decreased at later developmental stages only in the E11.5 Epha4 deletion mutant. These results suggest that EphA4, in cooperation with an FGF signal, contributes to the maintenance of RGC self-renewal and repression of RGC differentiation through the neuronal lineage. This function of EphA4 is especially critical and uncompensated in early stages of corticogenesis, and thus deletion at E11.5 reduces the size of the neonatal cortex.

  1. S100A6 (calcyclin) is a novel marker of neural stem cells and astrocyte precursors in the subgranular zone of the adult mouse hippocampus.

    Science.gov (United States)

    Yamada, Jun; Jinno, Shozo

    2014-01-01

    S100A6 (calcyclin), an EF-hand calcium binding protein, is considered to play various roles in the brain, for example, cell proliferation and differentiation, calcium homeostasis, and neuronal degeneration. In addition to some limbic nuclei, S100A6 is distributed in the rostral migratory stream, one of the major neurogenic niches of the adult brain. However, the potential involvement of S100A6 in adult neurogenesis remains unclear. In this study, we aimed to elucidate the role of S100A6 in the other major neurogenic niche, the subgranular zone of the dentate gyrus in the adult mouse hippocampus. Immunofluorescent multiple labeling showed that S100A6 was highly expressed in neural stem cells labeled by sex determining region Y-box 2, brain lipid-binding protein protein and glial fibrillary acidic protein. S100A6+ cells often extended a long process typical of radial glial morphology. In addition, S100A6 was found in some S100β+ astrocyte lineage cells. Interestingly, proliferating cell nuclear antigen was detected in a fraction of S100A6+/S100β+ cells. These cells were considered to be lineage-restricted astrocyte precursors maintaining mitotic potential. On the other hand, S100A6 was rarely seen in neural lineage cells labeled by T-box brain protein 2, doublecortin, calretinin and calbindin D28K. Cell fate-tracing experiment using BrdU showed that the majority of newly generated immature astrocytes were immunoreactive for S100A6, while mature astrocytes lacked S100A6 immunoreactivity. Administration of S100 protein inhibitor, trifluoperazine, caused a reduction in production of S100β+ astrocyte lineage cells, but had no impact on neurogenesis. Overall, our data provide the first evidence that S100A6 is a specific marker of neural stem cells and astrocyte precursors, and may be especially important for generation of astrocytes in the adult hippocampus. Copyright © 2013 Wiley Periodicals, Inc.

  2. Laser method of biological activity stimulation of cryoconserved hemopoietic tissue transplant

    Science.gov (United States)

    Khyznyak, Anatoly I.; Lesnik, Svetlana A.; Kogut, Georgy I.; Glukhenkaya, Galina T.

    1994-02-01

    The biological activity of cryoconserved fetal liver cells of mice (FLM) having undergone the He-Ne laser action has been estimated by the efficiency of their transplantation to mice- recipients exposed to lethal x-ray dose. The survival rate 30 days after x-ray exposure for those mice was 75% in comparison with 70% for mice with cryoconserved nonirradiated graft. The trial animals' peripheral blood investigations have been made. The obtained results indicate that the laser method of cryoconserved cells stimulation can help to increase the therapeutic efficiency of mielotransplantation.

  3. Studies on trigonelline from Moringa oleifera and its in vitro regulation by feeding precursor in cell cultures

    Directory of Open Access Journals (Sweden)

    Manas Mathur

    2012-04-01

    Full Text Available Trigonelline (N-methylnicotinate biosynthesized from nicotinate is one of the metabolically active pyridine alkaloid, widely distributed in plant kingdom. In the present study trigonelline has been isolated from various plant parts and callus cultures of Moringa oleifera Lam., Moringaceae, and was identified using TLC, GLC, GC-MS, which was comparable to that of the standard trigonelline. The trigonelline recovery was found to be maximum in the pods and minimum in flowers. In order to enhance the production of trigonelline in vitro grown cultures, different treatment doses of nicotinic acid (250, 500 and 750 mg L-1 were supplemented in the medium as precursor. Maximum increase (up to 1.10 fold was observed in the treatment dose of 500 mg L-1 of nicotinic acid.

  4. Highly conductive, multi-layer composite precursor composition to fuel cell flow field plate or bipolar plate

    Science.gov (United States)

    Jang, Bor Z [Centerville, OH; Zhamu, Aruna [Centerville, OH; Guo, Jiusheng [Centerville, OH

    2011-02-15

    This invention provides a moldable, multiple-layer composite composition, which is a precursor to an electrically conductive composite flow field plate or bipolar plate. In one preferred embodiment, the composition comprises a plurality of conductive sheets and a plurality of mixture layers of a curable resin and conductive fillers, wherein (A) each conductive sheet is attached to at least one resin-filler mixture layer; (B) at least one of the conductive sheets comprises flexible graphite; and (C) at least one resin-filler mixture layer comprises a thermosetting resin and conductive fillers with the fillers being present in a sufficient quantity to render the resulting flow field plate or bipolar plate electrically conductive with a conductivity no less than 100 S/cm and thickness-direction areal conductivity no less than 200 S/cm.sup.2.

  5. The eukaryotic translation elongation factor eEF1A2 induces neoplastic properties and mediates tumorigenic effects of ZNF217 in precursor cells of human ovarian carcinomas

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Yu; Wong, Nicholas; Guan, Yinghui; Salamanca, Clara M.; Cheng, Jung Chien; Lee, Jonathan M.; Gray, Joe W.; Auersperg, Nelly

    2008-04-25

    Ovarian epithelial carcinomas (OEC) frequently exhibit amplifications at the 20q13 locus which is the site of several oncogenes, including the eukaryotic elongation factor EEF1A2 and the transcription factor ZNF217. We reported previously that overexpressed ZNF217 induces neoplastic characteristics in precursor cells of OEC. Unexpectedly, ZNF217, which is a transcriptional repressor, enhanced expression of eEF1A2. In this study, array comparative genomic hybridization, single nucleotide polymorphism and Affymetrix analysis of ZNF217-overexpressing cell lines confirmed consistently increased expression of eEF1A2 but not of other oncogenes, and revealed early changes in EEF1A2 gene copy numbers and increased expression at crisis during immortalization. We defined the influence of eEF1A2 overexpression on immortalized ovarian surface epithelial cells, and investigated interrelationships between effects of ZNF217 and eEF1A2 on cellular phenotypes. Lentivirally induced eEF1A2 overexpression caused delayed crisis, apoptosis resistance and increases in serum-independence, saturation densities, and anchorage independence. siRNA to eEF1A2 reversed apoptosis resistance and reduced anchorage independence in eEF1A2-overexpressing lines. Remarkably, siRNA to eEF1A2 was equally efficient in inhibiting both anchorage independence and resistance to apoptosis conferred by ZNF217 overexpression. Our data define neoplastic properties that are caused by eEF1A2 in nontumorigenic ovarian cancer precursor cells, and suggest that eEF1A2 plays a role in mediating ZNF217-induced neoplastic progression.

  6. Sphingosine kinases modulate the secretion of amyloid β precursor protein from SH-SY5Y neuroblastoma cells: the role of α-synuclein.

    Science.gov (United States)

    Jesko, Henryk; Okada, Taro; Strosznajder, Robert P; Nakamura, Shun-ichi

    2014-01-01

    Sphingosine kinases (SphK 1&2) are involved in the regulation of cell survival, differentiation and neurotransmitter secretion. Current data suggest potential links between sphingolipid signalling, α-synuclein (ASN) and Alzheimer's disease (AD). Our aim was to investigate the possible role of SphKs and ASN in the regulation of the production and secretion of the amyloid β precursor protein (APP). We have previously shown that ASN intensified the secretion and toxicity of amyloid β (Aβ) to the point where it caused cell death. Our current results show that APP, the precursor protein for Aβ, is also influenced by ASN. The stable overexpression of wtASN in SH-SY5Y cells caused a three-fold, significant increase of the cellular APP level. This suggests that the influence of ASN on Aβ metabolism may actually occur at the level of APP protein rather than only through the changes of its cleavage into Aβ. To elucidate the mechanisms of APP modulation the cells were exposed to S1P and an SphK inhibitor (SKI). 72 h S1P treatment at 5 µM caused a nearly 50% reduction of the cellular APP signal. S1P also caused a tendency towards higher APP secretion, though the results were insignificant. The inhibition of SphKs decreased medium APP levels in a dose-dependent manner, reaching significance at 5 µM SKI with a correspondingly elevated intracellular level. Thus, it is reasonable to expect that in fact the influence of SphK activity on APP might be pro-secretory. This would also be in agreement with numerous articles on SphK-dependent secretion in the literature. The chronic nature of AD further suggests that subtle alterations in APP metabolism could have the potential to drive important changes in brain condition.

  7. BDNF Increases Survival and Neuronal Differentiation of Human Neural Precursor Cells Cotransplanted with a Nanofiber Gel to the Auditory Nerve in a Rat Model of Neuronal Damage

    Directory of Open Access Journals (Sweden)

    Yu Jiao

    2014-01-01

    Full Text Available Objectives. To study possible nerve regeneration of a damaged auditory nerve by the use of stem cell transplantation. Methods. We transplanted HNPCs to the rat AN trunk by the internal auditory meatus (IAM. Furthermore, we studied if addition of BDNF affects survival and phenotypic differentiation of the grafted HNPCs. A bioactive nanofiber gel (PA gel, in selected groups mixed with BDNF, was applied close to the implanted cells. Before transplantation, all rats had been deafened by a round window niche application of β-bungarotoxin. This neurotoxin causes a selective toxic destruction of the AN while keeping the hair cells intact. Results. Overall, HNPCs survived well for up to six weeks in all groups. However, transplants receiving the BDNF-containing PA gel demonstrated significantly higher numbers of HNPCs and neuronal differentiation. At six weeks, a majority of the HNPCs had migrated into the brain stem and differentiated. Differentiated human cells as well as neurites were observed in the vicinity of the cochlear nucleus. Conclusion. Our results indicate that human neural precursor cells (HNPC integration with host tissue benefits from additional brain derived neurotrophic factor (BDNF treatment and that these cells appear to be good candidates for further regenerative studies on the auditory nerve (AN.

  8. Properties of Retinal Precursor Cells Grown on Vertically Aligned Multiwalled Carbon Nanotubes Generated for the Modification of Retinal Implant-Embedded Microelectrode Arrays

    Directory of Open Access Journals (Sweden)

    Sandra Johnen

    2016-01-01

    Full Text Available Background. To analyze the biocompatibility of vertically aligned multiwalled carbon nanotubes (MWCNT, used as nanomodification to optimize the properties of prostheses-embedded microelectrodes that induce electrical stimulation of surviving retinal cells. Methods. MWCNT were synthesized on silicon wafers. Their growth was achieved by iron particles (Fe or mixtures of iron-platinum (Fe-Pt and iron-titanium (Fe-Ti acting as catalysts. Viability, growth, adhesion, and gene expression of L-929 and retinal precursor (R28 cells were analyzed after nondirect and direct contact. Results. Nondirect contact had almost no influence on cell growth, as measured in comparison to reference materials with defined levels of cytotoxicity. Both cell types exhibited good proliferation properties on each MWCNT-coated wafer. Viability ranged from 95.9 to 99.8%, in which better survival was observed for nonfunctionalized MWCNT generated with the Fe-Pt and Fe-Ti catalyst mixtures. R28 cells grown on the MWCNT-coated wafers showed a decreased gene expression associated with neural and glial properties. Expression of the cell cycle-related genes CCNC, MYC, and TP53 was slightly downregulated. Cultivation on plasma-treated MWCNT did not lead to additional changes. Conclusions. All tested MWCNT-covered slices showed good biocompatibility profiles, confirming that this nanotechnology is a promising tool to improve prostheses bearing electrodes which connect with retinal tissue.

  9. Effect of leukemia inhibitory factor on long-term propagation of precursor cells derived from rat forebrain subventricular zone and ventral mesencephalon

    DEFF Research Database (Denmark)

    Andersen, Rikke K; Zimmer, Jens; Wahlberg, Lars U

    2008-01-01

    propagated and maintained for more than 6 months with a cell population doubling time of 21.5 days. The replacement of EGF by leukemia inhibitory factor (LIF) resulted in a cell population doubling time of 19.8 days, corresponding to a 10-fold increase in estimated cell numbers over a period of 70 days......Tissue blocks containing neural precursor cells were isolated from the rat forebrain subventricular zone (SVZ) and ventral mesencephalon (VM) and propagated as neural tissue-spheres (NTS). In the presence of fibroblast growth factor-2 (FGF2) and epidermal growth factor (EGF), SVZ-derived NTS were......, at which point these NTS ceased to grow. In the presence of FGF2 and LIF, VM-derived NTS displayed a cell population doubling time of 24.6 days, which was maintained over a period of more than 200 days. However, when LIF was replaced by EGF, the cell numbers only increased 1.2 fold over 50 days. Using...

  10. IL-7 and IL-15 instruct the generation of human memory stem T cells from naive precursors

    National Research Council Canada - National Science Library

    Cieri, Nicoletta; Camisa, Barbara; Cocchiarella, Fabienne; Forcato, Mattia; Oliveira, Giacomo; Provasi, Elena; Bondanza, Attilio; Bordignon, Claudio; Peccatori, Jacopo; Ciceri, Fabio; Lupo-Stanghellini, Maria Teresa; Mavilio, Fulvio; Mondino, Anna; Bicciato, Silvio; Recchia, Alessandra; Bonini, Chiara

    2013-01-01

    Long-living memory stem T cells (T(SCM)) with the ability to self-renew and the plasticity to differentiate into potent effectors could be valuable weapons in adoptive T-cell therapy against cancer...

  11. Protective Effects of Squid Ink Extract Towards Hemopoietic Injuries Induced by Cyclophosphamine

    OpenAIRE

    Zhong, Jie-Ping; Wang, Guang; Shang, Jiang-Hua; Pan, Jiang-Qiu; Li, Kun; Huang, Yan; Liu, Hua-Zhong

    2009-01-01

    To investigate the protective effects of squid ink in chemotherapy, BALB/c mice were used as animal models of injuries induced by cyclophosphamine, a well known chemotherapeutic drug. The mice were randomly divided into five groups with the same number of males and females in each group. At the end of the experiment, animals were sacrificed to investigate organ indexes and antioxidant ability of the spleen, peripheral blood profile and quantities of bone marrow nucleated cells. Results showed...

  12. B-cell recovery after stem cell transplantation of Artemis-deficient SCID requires elimination of autologous bone marrow precursor-B-cells.

    NARCIS (Netherlands)

    Burg, M. van der; Weemaes, C.M.R.; Preijers, F.W.M.B.; Brons, P.P.T.; Barendregt, B.H.; Tol, M. van; Hoogerbrugge, P.M.; Dongen, J.J.M. van

    2006-01-01

    Severe combined immunodeficiencies (SCID) are commonly fatal early in life. Adequate diagnosis and rapid institution of treatment, such as allogeneic stem cell transplantation (SCT), is essential. Several studies demonstrated that reconstitution of B-cell function after SCT is better in B-positive

  13. Direct observations of dynamic PtCo interactions in fuel cell catalyst precursors at the atomic level using E(S)TEM.

    Science.gov (United States)

    Ward, M R; Theobald, B; Sharman, J; Boyes, E D; Gai, P L

    2018-02-01

    Reduction reactions in practical bimetallic platinum-cobalt electrode catalyst precursors containing platinum, cobalt and cobalt oxides in hydrogen at 200, 450 and 700 °C for 6 h have been studied in situ using an aberration corrected environmental (scanning) transmission electron microscope (AC E(S)TEM). Little difference was observed in reduction at 200 °C but during and after reduction at 450 °C, small nanoparticles less than 3 nm in diameter with tetragonal PtCo structures were observed and limited Pt 3 Co ordering could be seen on the surfaces of larger nanoparticles. During and after reduction at 700 °C, fully ordered Pt 3 Co and PtCo nanoparticles larger than 4 nm were produced and the average nanoparticle size almost trebled relative to the fresh precursor. After reduction at 450 and 700 °C, most nanoparticles were disordered platinum/cobalt alloys with fcc structure. After reduction at 700 °C many of the smallest nanoparticles disappeared suggesting Ostwald ripening had occurred. Mechanisms concerning the thermal transformation of mixed cobalt and platinum species are discussed, offering new insights into the creation of bimetallic platinum-cobalt nanoparticles in fuel cell catalysts. © 2017 The Authors Journal of Microscopy © 2017 Royal Microscopical Society.

  14. Enhanced Biosynthesis of Withanolides by Elicitation and Precursor Feeding in Cell Suspension Culture of Withania somnifera (L.) Dunal in Shake-Flask Culture and Bioreactor

    Science.gov (United States)

    Sivanandhan, Ganeshan; Selvaraj, Natesan; Ganapathi, Andy; Manickavasagam, Markandan

    2014-01-01

    The present study investigated the biosynthesis of major and minor withanolides of Withania somnifera in cell suspension culture using shake-flask culture and bioreactor by exploiting elicitation and precursor feeding strategies. Elicitors like cadmium chloride, aluminium chloride and chitosan, precursors such as cholesterol, mevalonic acid and squalene were examined. Maximum total withanolides detected [withanolide A (7606.75 mg), withanolide B (4826.05 mg), withaferin A (3732.81 mg), withanone (6538.65 mg), 12 deoxy withanstramonolide (3176.63 mg), withanoside IV (2623.21 mg) and withanoside V (2861.18 mg)] were achieved in the combined treatment of chitosan (100 mg/l) and squalene (6 mM) along with 1 mg/l picloram, 0.5 mg/l KN, 200 mg/l L-glutamine and 5% sucrose in culture at 4 h and 48 h exposure times respectively on 28th day of culture in bioreactor. We obtained higher concentrations of total withanolides in shake-flask culture (2.13-fold) as well as bioreactor (1.66-fold) when compared to control treatments. This optimized protocol can be utilized for commercial level production of withanolides from suspension culture using industrial bioreactors in a short culture period. PMID:25089711

  15. Enhanced biosynthesis of withanolides by elicitation and precursor feeding in cell suspension culture of Withania somnifera (L. Dunal in shake-flask culture and bioreactor.

    Directory of Open Access Journals (Sweden)

    Ganeshan Sivanandhan

    Full Text Available The present study investigated the biosynthesis of major and minor withanolides of Withania somnifera in cell suspension culture using shake-flask culture and bioreactor by exploiting elicitation and precursor feeding strategies. Elicitors like cadmium chloride, aluminium chloride and chitosan, precursors such as cholesterol, mevalonic acid and squalene were examined. Maximum total withanolides detected [withanolide A (7606.75 mg, withanolide B (4826.05 mg, withaferin A (3732.81 mg, withanone (6538.65 mg, 12 deoxy withanstramonolide (3176.63 mg, withanoside IV (2623.21 mg and withanoside V (2861.18 mg] were achieved in the combined treatment of chitosan (100 mg/l and squalene (6 mM along with 1 mg/l picloram, 0.5 mg/l KN, 200 mg/l L-glutamine and 5% sucrose in culture at 4 h and 48 h exposure times respectively on 28th day of culture in bioreactor. We obtained higher concentrations of total withanolides in shake-flask culture (2.13-fold as well as bioreactor (1.66-fold when compared to control treatments. This optimized protocol can be utilized for commercial level production of withanolides from suspension culture using industrial bioreactors in a short culture period.

  16. An experimental study of chondrule formation from chondritic precursors via evaporation and condensation in Knudsen cell: Shock heating model of dust aggregates

    Science.gov (United States)

    Imae, Naoya; Isobe, Hiroshi

    2017-09-01

    Chondrules, igneous objects of ∼1 mm in diameter, formed in the earliest solar system via a transient heating event, are divided into two types: main (type I, FeO-poor) and minor (type II, FeO-rich). Using various chondritic materials for different redox conditions and grain sizes, chondrule reproduction experiments were carried out at IW-2 to IW-3.8, with cooling rates mainly ∼100°C/h, with peak temperatures mainly at 1450 °C, and mainly at 100 Pa in a Knudsen cell providing near chemical equilibrium between the charge and the surrounding gas at the peak temperatures. Vapor pressures in the capsule were controlled using solid buffers. After and during the significant evaporation of the iron component from the metallic iron-poor starting materials in near equilibrium, crystallization occurred. This resulted in the formation of a product similar to the type I chondrules. Dusty olivine grains occurred in charges that had precursor type II chondrules containing coarse ferroan olivine, but such grains are not common in type I chondrules. Therefore fine-grained ferroan matrices rather than type II chondrules are main precursor for type I chondrules. The type I chondrules would have evolved via evaporation and condensation in the similar conditions to the present experimental system. Residual gas, which escaped in experiments, could have condensed to form matrices, leading to complementary compositions. Clusters of matrices and primordial chondrules could have been recycled to form main-generation chondrules originated from the shock heating.

  17. Enhanced production of vanillin flavour metabolites by precursor feeding in cell suspension cultures of Decalepis hamiltonii Wight & Arn., in shake flask culture.

    Science.gov (United States)

    Matam, Pradeep; Parvatam, Giridhar; Shetty, Nandini P

    2017-12-01

    The flavour rich tuberous roots of Decalepis hamiltonii are known for its edible and medicinal use and have become endangered due to commercial over-exploitation. Besides 2-Hydroxy-4-methoxy benzaldehyde (2H4MB), other flavour metabolites in tuberous roots include vanillin, 4-Methoxy Cinnamic acid derivatives, aromatic alcohols etc. So far, there are no reports on the pathway of 2H4MB biosynthesis nor there is an organized work on biotransformation using normal and cell suspension cultures for obtaining these metabolites using precursors. The main aim of the study is to develop a method for enhanced production of flavour attributing metabolites through ferulic acid (FA) feeding to the D. hamiltonii callus culture medium. Biomass of D. hamiltonii cell suspension cultures was maximum (200.38 ± 1.56 g/l) by 4th week. Maximum production of 2H4MB was recorded on 4th week (0.08 ± 0.01 mg/100 g dry weight) as quantified by HPLC. Addition of 0.1-1.5 mM ferulic acid as precursor in the culture medium showed significant (p < 0.001) effect on suspension cultures biomass and respective phenylpropanoid metabolites content and 2H4MB accumulation. The maximum accumulation of vanillin, 2H4MB, vanillic acid, ferulic acid were of 0.1 ± 0.02 mg/100 g, 0.44 ± 0.01 mg/100 g, 0.52 ± 0.04 mg/100 g, 0.18 ± 0.02 mg/100 g DW respectively in 4 weeks of cultured cells supplemented with 1 mM ferulic acid as a precursor. The results indicate that, substantial increase in the levels of flavour metabolites in D. hamiltonii callus suspension culture was achieved. This would be having implications in biosynthesis of respective vanilla flavour attributing metabolites at very high levels for their large scale production.

  18. A facile route to inverted polymer solar cells using a precursor based zinc oxide electron transport layer

    OpenAIRE

    de Bruyn, P.; Moet, D. J. D.; Blom, P. W. M.

    2010-01-01

    Inverted polymer: fullerene solar cells with ZnO and MoO(3) transport layers are demonstrated. ZnO films are prepared through spin casting of a zinc acetylacetonate hydrate solution, followed by low temperature annealing under ambient conditions. The performance of solar cells with an inverted structure is shown to be equivalent to that of conventional cells with a bottom-anode-top-cathode configuration for three efficient polymer: fullerene systems. (C) 2010 Elsevier B.V. All rights reserved.

  19. Cytokine-dependent long-term culture of highly enriched precursors of hematopoietic progenitor cells from human bone marrow.

    Science.gov (United States)

    Brandt, J; Srour, E F; van Besien, K; Briddell, R A; Hoffman, R

    1990-09-01

    Human marrow cells positive for the CD34 antigen but not expressing HLA-DR, CD15, or CD71 antigens were isolated. In a liquid culture system supplemented with 48-hourly additions of recombinant interleukins IL-1 alpha, IL-3, IL-6, or granulocyte/macrophage colony-stimulating factor (GM-CSF), these cells were capable of sustaining in vitro hematopoiesis for up to eight weeks. The establishment of an adherent cell layer was never observed. Cultures containing no exogenous cytokine produced clonogenic cells for only 1 wk. IL-1 alpha and IL-6 were alone able to support hematopoiesis for 2 or 3 wk. Cells maintained with GM-CSF proliferated and contained assayable colony-forming cells for 3 or 4 wk, while maximal cellular expansion and generation of assayable progenitor cells occurred in the presence of IL-3 for 4-5 wk. When IL-3 was combined with IL-1 alpha or IL-6, hematopoiesis was sustained for 8 wks. Basophil numbers were markedly increased in the presence of IL-3. These studies indicate that marrow subpopulations can sustain hematopoiesis in vitro in the presence of repeated additions of cytokines. We conclude that a major function of marrow adherent cells in long-term cultures is that of providing cytokines which promote the proliferation and differentiation of primitive hematopoietic cells.

  20. The E1 copper binding domain of full-length amyloid precursor protein mitigates copper-induced growth inhibition in brain metastatic prostate cancer DU145 cells

    Energy Technology Data Exchange (ETDEWEB)

    Gough, Mallory, E-mail: m.gough1@lancaster.ac.uk; Blanthorn-Hazell, Sophee, E-mail: s.blanthorn-hazell@lancaster.ac.uk; Delury, Craig, E-mail: c.delury@lancaster.ac.uk; Parkin, Edward, E-mail: e.parkin@lancaster.ac.uk

    2014-10-31

    Highlights: • Copper levels are elevated in the tumour microenvironment. • APP mitigates copper-induced growth inhibition of DU145 prostate cancer (PCa) cells. • The APP intracellular domain is a prerequisite; soluble forms have no effect. • The E1 CuBD of APP is also a prerequisite. • APP copper binding potentially mitigates copper-induced PCa cell growth inhibition. - Abstract: Copper plays an important role in the aetiology and growth of tumours and levels of the metal are increased in the serum and tumour tissue of patients affected by a range of cancers including prostate cancer (PCa). The molecular mechanisms that enable cancer cells to proliferate in the presence of elevated copper levels are, therefore, of key importance in our understanding of tumour growth progression. In the current study, we have examined the role played by the amyloid precursor protein (APP) in mitigating copper-induced growth inhibition of the PCa cell line, DU145. A range of APP molecular constructs were stably over-expressed in DU145 cells and their effects on cell proliferation in the presence of copper were monitored. Our results show that endogenous APP expression was induced by sub-toxic copper concentrations in DU145 cells and over-expression of the wild-type protein was able to mitigate copper-induced growth inhibition via a mechanism involving the cytosolic and E1 copper binding domains of the full-length protein. APP likely represents one of a range of copper binding proteins that PCa cells employ in order to ensure efficient proliferation despite elevated concentrations of the metal within the tumour microenvironment. Targeting the expression of such proteins may contribute to therapeutic strategies for the treatment of cancers.

  1. A facile route to inverted polymer solar cells using a precursor based zinc oxide electron transport layer

    NARCIS (Netherlands)

    Bruyn, P. de; Moet, D.J.D.; Blom, P.W.M.

    2010-01-01

    Inverted polymer:fullerene solar cells with ZnO and MoO3 transport layers are demonstrated. ZnO films are prepared through spin casting of a zinc acetylacetonate hydrate solution, followed by low temperature annealing under ambient conditions. The performance of solar cells with an inverted

  2. A facile route to inverted polymer solar cells using a precursor based zinc oxide electron transport layer

    NARCIS (Netherlands)

    de Bruyn, P.; Moet, D. J. D.; Blom, P. W. M.

    Inverted polymer: fullerene solar cells with ZnO and MoO(3) transport layers are demonstrated. ZnO films are prepared through spin casting of a zinc acetylacetonate hydrate solution, followed by low temperature annealing under ambient conditions. The performance of solar cells with an inverted

  3. Ultraviolet irradiation modulates MHC-alloreactive cytotoxic T-cell precursors involved in the onset of graft-versus-host disease

    Energy Technology Data Exchange (ETDEWEB)

    Prooijen, H.C. Van; Aarts-Riemens, M.I.; Weelden, H. Van (University Hospital, Utrecht (Netherlands)); Grijzenhout, M.A. (National Inst. of Public Health and Environmental Protection, Bilthoven (Netherlands))

    1992-05-01

    Ultraviolet B (UVB) irradiation of cellular blood components has been proposed as a new technology to prevent HLA sensitization in recipients. Earlier studies have shown that a dose of 2 J/cm[sup 2] abrogates the ability of lymphocytes to serve as stimulators in mixed lymphocyte cultures (MLC). In this study the authors evaluate the effect of UV energy on T-lymphocytes for the prevention of transfusion-associated graft-versus-host disease (TA-GvHD). The response of cytotoxic T-lymphocyte precursors against host alloantigens was almost undetectable at a dose of 0.5 J/cm[sup 2]. T-cell proliferation in MLC or in response to phytohaemagglutinin was inhibited by more than 95% at doses of 1 J/cm[sup 2] or higher. The data suggest that UV irradiation can be used to prevent both HLA sensitization and TA-GvHD in recipients. (Author).

  4. Preparation of Pt-Re/Vulcan carbon nanocomposites using a single-source molecular precursor and relative performance as a direct methanol fuel cell electrooxidation catalyst.

    Science.gov (United States)

    Anderson, Angela D; Deluga, Gregg A; Moore, Joshua T; Vergne, Matthew J; Hercules, David M; Kenik, Edward A; Lukehart, C M

    2004-09-01

    Pt-Re/Vulcan carbon powder nanocomposites have been prepared with total metal loadings of 18 wt.% and 40 wt.% using a new non-cluster (1:1)-PtRe bimetallic precursor as the source of metal. Pt-Re nanoparticles having an average diameter of ca. 6 nm and atomic stoichiometry near 1:1 are formed. TEM, on-particle HR-EDS, and powder XRD data are consistent with the formation of Pt-Re alloy nanoparticles having a hexagonal unit cell with cell constants of a = 2.77 A and c = 4.47 A. A nanocomposite prepared at higher total metal loading under more rigorous thermal treatment also contains Pt-Re alloy nanoparticles having a fcc unit cell structure (a = 3.95 A). The precise dependence of Pt-Re nanocrystal structure on the thermal history of the nanocomposite specimen has not been investigated in detail. While these Pt-Re/carbon nanocomposites are active as anode catalysts in operating direct methanol fuel cells, the measured performance is less than that of commercial Pt-Ru/carbon catalysts and has marginal practical importance.

  5. Baccatin III, a precursor for the semisynthesis of paclitaxel, inhibits the accumulation and suppressive activity of myeloid-derived suppressor cells in tumor-bearing mice.

    Science.gov (United States)

    Lee, Young-Hee; Lee, Young-Ran; Park, Chan-Su; Im, Sun-A; Song, Sukgil; Hong, Jin Tae; Whang, Bang Yeon; Kim, Kyungjae; Lee, Chong-Kil

    2014-08-01

    Myeloid-derived suppressor cells (MDSCs) mediate tumor-associated immune suppression in both cancer patients and tumor-bearing animals. Reduction or elimination of MDSCs reduces the rate of tumor progression and improves cancer therapies that employ mechanisms of immunity. Here we show that baccatin III, which is the precursor for the semisynthesis of paclitaxel, exerts anti-tumor immunomodulatory activity in very low doses (0.05-0.5mg/kg), although it is regarded as an inactive derivative of paclitaxel. Oral administration of baccatin III significantly reduced the growth of tumors induced by engrafting BALB/c mice with either 4 T1 mammary carcinoma or CT26 colon cancer cells. Baccatin III (0.5mg/kg) did not exert anti-tumor activity in athymic nude mice. Baccatin III decreased the accumulation of MDSCs in the spleens of the tumor-bearing mice. Furthermore, MDSCs isolated from baccatin III-treated mice, compared with those isolated from vehicle-treated mice, had a significantly reduced suppressive effect on T cells treated with the anti-CD3 and anti-CD28 monoclonal antibodies. Moreover, these cells produced significantly reduced amounts of reactive oxygen species and nitric oxide. These results suggest that baccatin III reduced tumor progression by inhibiting the accumulation and suppressive function of MDSCs. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Neural precursors exhibit distinctly different patterns of cell migration upon transplantation during either the acute or chronic phase of EAE: a serial MR imaging study.

    Science.gov (United States)

    Muja, Naser; Cohen, Mikhal E; Zhang, Jiangyang; Kim, Heechul; Gilad, Assaf A; Walczak, Piotr; Ben-Hur, Tamir; Bulte, Jeff W M

    2011-06-01

    As the complex pathogenesis of multiple sclerosis contributes to spatiotemporal variations in the trophic micromilieu of the central nervous system, the optimal intervention period for cell-replacement therapy must be systematically defined. We applied serial, 3D high-resolution magnetic resonance imaging to transplanted neural precursor cells (NPCs) labeled with superparamagnetic iron oxide nanoparticles and 5-bromo-2-deoxyuridine, and compared the migration pattern of NPCs in acute inflamed (n = 10) versus chronic demyelinated (n = 9) brains of mice induced with experimental allergic encephalomyelitis (EAE). Serial in vivo and ex-vivo 3D magnetic resonance imaging revealed that NPCs migrated 2.5 ± 1.3 mm along the corpus callosum in acute EAE. In chronic EAE, cell migration was slightly reduced (2.3 ± 1.3 mm) and only occurred in the lateral side of transplantation. Surprisingly, in 6/10 acute EAE brains, NPCs were found to migrate in a radial pattern along RECA-1(+) cortical blood vessels, in a pattern hitherto only reported for migrating glioblastoma cells. This striking radial biodistribution pattern was not detected in either chronic EAE or disease-free control brains. In both acute and chronic EAE brain, Iba1(+) microglia/macrophage number was significantly higher in central nervous system regions containing migrating NPCs. The existence of differential NPC migration patterns is an important consideration for implementing future translational studies in multiple sclerosis patients with variable disease. Copyright © 2011 Wiley-Liss, Inc.

  7. The NG2 Proteoglycan Protects Oligodendrocyte Precursor Cells against Oxidative Stress via Interaction with OMI/HtrA2.

    Science.gov (United States)

    Maus, Frank; Sakry, Dominik; Binamé, Fabien; Karram, Khalad; Rajalingam, Krishnaraj; Watts, Colin; Heywood, Richard; Krüger, Rejko; Stegmüller, Judith; Werner, Hauke B; Nave, Klaus-Armin; Krämer-Albers, Eva-Maria; Trotter, Jacqueline

    2015-01-01

    The NG2 proteoglycan is characteristically expressed by oligodendrocyte progenitor cells (OPC) and also by aggressive brain tumours highly resistant to chemo- and radiation therapy. Oligodendrocyte-lineage cells are particularly sensitive to stress resulting in cell death in white matter after hypoxic or ischemic insults of premature infants and destruction of OPC in some types of Multiple Sclerosis lesions. Here we show that the NG2 proteoglycan binds OMI/HtrA2, a mitochondrial serine protease which is released from damaged mitochondria into the cytosol in response to stress. In the cytosol, OMI/HtrA2 initiates apoptosis by proteolytic degradation of anti-apoptotic factors. OPC in which NG2 has been downregulated by siRNA, or OPC from the NG2-knockout mouse show an increased sensitivity to oxidative stress evidenced by increased cell death. The proapoptotic protease activity of OMI/HtrA2 in the cytosol can be reduced by the interaction with NG2. Human glioma expressing high levels of NG2 are less sensitive to oxidative stress than those with lower NG2 expression and reducing NG2 expression by siRNA increases cell death in response to oxidative stress. Binding of NG2 to OMI/HtrA2 may thus help protect cells against oxidative stress-induced cell death. This interaction is likely to contribute to the high chemo- and radioresistance of glioma.

  8. Physical exercise counteracts MPTP-induced changes in neural precursor cell proliferation in the hippocampus and restores spatial learning but not memory performance in the water maze.

    Science.gov (United States)

    Klein, C; Rasińska, J; Empl, L; Sparenberg, M; Poshtiban, A; Hain, E G; Iggena, D; Rivalan, M; Winter, Y; Steiner, B

    2016-07-01

    Parkinson's disease (PD) is characterized by a continuous loss of dopaminergic neurons in the substantia nigra, which not only leads to characteristic motor symptoms but also to cognitive impairments. Physical exercise has been shown to improve hippocampus-dependent cognitive functions in PD patients. Animal studies have demonstrated the involvement of adult hippocampal neurogenesis in exercise-induced improvements of visuo-spatial learning and memory. Here, we investigated the direct impact of voluntary wheel running on hippocampal neurogenesis and spatial learning and memory in the Morris water maze (MWM) using the1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model of PD. We also analyzed striatal and hippocampal dopamine transmission and mRNA expression levels of dopamine receptors. We show that MPTP-induced spatial learning deficits were alleviated by short-term physical exercise but not MPTP-induced spatial memory impairments in either exercise intervention group. Neural precursor proliferation was transiently altered in MPTP-treated mice, while the cell survival was increased by exercise. Dopamine was progressively depleted by MPTP and its turnover altered by exercise. In addition, gene expression of dopamine receptor D1/D5 was transiently upregulated following MPTP treatment but not affected by physical exercise. Our findings suggest that physical exercise benefits spatial learning but not memory performance in the MWM after MPTP-induced dopamine depletion by restoring precursor cell proliferation in the hippocampus and influencing dopamine transmission. This adds to the understanding of cognitive decline and mechanisms for potential improvements by physical exercise in PD patients. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Manoyl Oxide (13R), the Biosynthetic Precursor of Forskolin, Is Synthesized in Specialized Root Cork Cells in Coleus forskohlii1[W][OPEN

    Science.gov (United States)

    Pateraki, Irini; Andersen-Ranberg, Johan; Hamberger, Britta; Heskes, Allison Maree; Martens, Helle Juel; Zerbe, Philipp; Bach, Søren Spanner; Møller, Birger Lindberg; Bohlmann, Jörg; Hamberger, Björn

    2014-01-01

    Forskolin, a complex labdane diterpenoid found in the root of Coleus forskohlii (Lamiaceae), has received attention for its broad range of pharmacological activities, yet the biosynthesis has not been elucidated. We detected forskolin in the root cork of C. forskohlii in a specialized cell type containing characteristic structures with histochemical properties consistent with oil bodies. Organelle purification and chemical analysis confirmed the localization of forskolin and of its simplest diterpene precursor backbone, (13R) manoyl oxide, to the oil bodies. The labdane diterpene backbone is typically synthesized by two successive reactions catalyzed by two distinct classes of diterpene synthases. We have recently described the identification of a small gene family of diterpene synthase candidates (CfTPSs) in C. forskohlii. Here, we report the functional characterization of four CfTPSs using in vitro and in planta assays. CfTPS2, which synthesizes the intermediate copal-8-ol diphosphate, in combination with CfTPS3 resulted in the stereospecific formation of (13R) manoyl oxide, while the combination of CfTPS1 and CfTPS3 or CfTPS4 led to formation of miltiradiene, precursor of abietane diterpenoids in C. forskohlii. Expression profiling and phylogenetic analysis of the CfTPS family further support the functional diversification and distinct roles of the individual diterpene synthases and the involvement of CfTPS1 to CfTPS4 in specialized metabolism and of CfTPS14 and CfTPS15 in general metabolism. Our findings pave the way toward the discovery of the remaining components of the pathway to forskolin, likely localized in this specialized cell type, and support a role of oil bodies as storage organelles for lipophilic bioactive metabolites. PMID:24481136

  10. The influence of anti-inflammatory medication on exercise-induced myogenic precursor cell responses in humans

    DEFF Research Database (Denmark)

    Mackey, A L; Kjær, Michael; Dandanell, Sune

    2007-01-01

    62 ml x kg(-1) x min(-1)) volunteered for the study, which involved running 36 km. They were divided into two groups and received either 100 mg indomethacin per day or placebo. Muscle biopsies collected before the run and on days 1, 3, and 8 afterward were analyzed for satellite cells...... by immunohistochemistry with the aid of neural cell adhesion molecule (NCAM) and fetal antigen-1 (FA1) antibodies. Muscle biopsies were also collected from untrained individuals for comparison. Compared with preexercise levels, a 27% increase in the number of NCAM+ cells was observed on day 8 postexercise in the placebo...

  11. Cytokine-dependent long-term culture of highly enriched precursors of hematopoietic progenitor cells from human bone marrow.

    OpenAIRE

    Brandt, J.; Srour, E F; van Besien, K.; Briddell, R A; Hoffman, R.

    1990-01-01

    Human marrow cells positive for the CD34 antigen but not expressing HLA-DR, CD15, or CD71 antigens were isolated. In a liquid culture system supplemented with 48-hourly additions of recombinant interleukins IL-1 alpha, IL-3, IL-6, or granulocyte/macrophage colony-stimulating factor (GM-CSF), these cells were capable of sustaining in vitro hematopoiesis for up to eight weeks. The establishment of an adherent cell layer was never observed. Cultures containing no exogenous cytokine produced clon...

  12. Resultados do tratamento do carcinoma espinocelular anal e do seu precursor em doentes HIV-positivos Outcome of treatment of anal squamous cell carcinoma and its precursor in HIV-infected patients

    Directory of Open Access Journals (Sweden)

    Sidney Roberto Nadal

    2007-08-01

    Full Text Available OBJETIVO: A incidência de carcinomas espinocelulares anais vem aumentando nos doentes HIV-positivos. O tratamento consiste de radio e/ou quimioterapia, eventualmente seguidos pela ressecção do tumor. O objetivo é avaliar o seguimento desses doentes para verificar as recidivas e a evolução do NIAA para câncer. Apresentação da casuística da Equipe Técnica de Proctologia do Instituto de Infectologia Emílio Ribas, de São Paulo. MÉTODOS: Acompanhamos 45 doentes HIV-positivos portadores de carcinoma espinocelular anal e seu precursor no período de 1996 a 2006. Eram 30 neoplasias intra-epiteliais anais de alto grau (NIAA, tratadas com ressecção local e 15 carcinomas invasores do canal anal. Nove das 15 lesões invasivas foram submetidas ao esquema de Nigro isolado ou associado à ressecção local, amputação abdominoperineal ou colostomia para derivação. RESULTADOS: No seguimento ambulatorial das NIAA tivemos recidiva em 16,7% e não observamos evolução para carcinoma, num período mínimo de três anos. Entre os nove tumores submetidos ao esquema de Nigro, com ou sem operação complementar, cinco estão livres de tumor. Nenhum tratamento foi feito em cinco doentes. Em três, devido às péssimas condições clínicas, e em dois, pois recusaram tratamento. Outro teve diagnóstico na vigência de oclusão intestinal sendo submetido à colostomia de derivação. CONCLUSÃO: Concluímos que a NIAA pode reincidir após excisão local em doentes HIV-positivos, mas não evolui para carcinoma invasor e que os doentes de câncer anal invasor podem ser tratados da mesma maneira que a população soronegativa para o HIV desde que as condições clínicas o permitam.OBJECTIVE: Incidence of anal squamous cell carcinoma is increasing mainly among HIV-positive patients. Treatment consists of radiotherapy and chemotherapy, sometimes followed by tumor resection. The objective was to evaluate the follow-up of such patients to verify recurrences

  13. Effects of Intermittent Administration of Parathyroid Hormone (1-34 on Bone Differentiation in Stromal Precursor Antigen-1 Positive Human Periodontal Ligament Stem Cells

    Directory of Open Access Journals (Sweden)

    Xiaoxiao Wang

    2016-01-01

    Full Text Available Periodontitis is the most common cause of tooth loss and bone destruction in adults worldwide. Human periodontal ligament stem cells (hPDLSCs may represent promising new therapeutic biomaterials for tissue engineering applications. Stromal precursor antigen-1 (STRO-1 has been shown to have roles in adherence, proliferation, and multipotency. Parathyroid hormone (PTH has been shown to enhance proliferation in osteoblasts. Therefore, in this study, we aimed to compare the functions of STRO-1(+ and STRO-1(− hPDLSCs and to investigate the effects of PTH on the osteogenic capacity of STRO-1(+ hPDLSCs in order to evaluate their potential applications in the treatment of periodontitis. Our data showed that STRO-1(+ hPDLSCs expressed higher levels of the PTH-1 receptor (PTH1R than STRO-1(− hPDLSCs. In addition, intermittent PTH treatment enhanced the expression of PTH1R and osteogenesis-related genes in STRO-1(+ hPDLSCs. PTH-treated cells also exhibited increased alkaline phosphatase activity and mineralization ability. Therefore, STRO-1(+ hPDLSCs represented a more promising cell resource for biomaterials and tissue engineering applications. Intermittent PTH treatment improved the capacity for STRO-1(+ hPDLSCs to repair damaged tissue and ameliorate the symptoms of periodontitis.

  14. Differential effects of IL-2 and IL-6 on the development of three distinct precursor T-cell populations in the thymus.

    Science.gov (United States)

    Nakano, N; Kikutani, H; Kishimoto, T

    1990-01-01

    Three distinct T-cell precursors: bone marrow cells that express low levels of the Thy-1 antigen but no lineage markers (Thy-1-lo/BM); CD4-, CD8-, and CD3- thymocytes that express low levels of the Thy-1 antigen (Thy-1-lo/Thym); and CD4-, CD8-, and CD3- thymocytes that express high levels of the Thy-1 antigen and the IL-2 R alpha chain (Thy-1+/IL2R+) were isolated by fluorescence-activated cell sorter (FACS). These three populations expanded with different kinetics in the thymus of irradiated recipient mice after intrathymic transfer. When a high dose of human recombinant IL-2 (r-IL-2) or human recombinant IL-6 (r-IL-6) was administered, r-IL-6 accelerated donor Thy-1+/IL2R+ to differentiate, whereas r-IL-2 blocked normal differentiation and expansion of donor Thy-1-lo/Thym, but did not show any significant effect on donor Thy-1+/IL2R+. Neither r-IL-2 nor r-IL-6 worked directly on donor Thy-1-lo/BM in this transfer system.

  15. Neural precursor cell proliferation is disrupted through activation of the aryl hydrocarbon receptor by 2,3,7,8-tetrachlorodibenzo-p-dioxin.

    Science.gov (United States)

    Latchney, Sarah E; Lioy, Daniel T; Henry, Ellen C; Gasiewicz, Thomas A; Strathmann, Frederick G; Mayer-Pröschel, Margot; Opanashuk, Lisa A

    2011-02-01

    Neurogenesis involves the proliferation of multipotent neuroepithelial stem cells followed by differentiation into lineage-restricted neural precursor cells (NPCs) during the embryonic period. Interestingly, these progenitor cells express robust levels of the aryl hydrocarbon receptor (AhR), a ligand-activated transcription factor that regulates expression of genes important for growth regulation, and xenobiotic metabolism. Upon binding 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a pervasive environmental contaminant and potent AhR ligand, AhR, is activated and disrupts gene expression patterns to produce cellular toxicity. Because of its widespread distribution in the brain during critical proliferative phases of neurogenesis, it is conceivable that AhR participates in NPC expansion. Therefore, this study tested the hypothesis that AhR activation by TCDD disrupts signaling events that regulate NPC proliferation. The C17.2 NPC line served as a model system to (1) assess whether NPCs are targets for TCDD-induced neurotoxicity and (2) characterize the effects of TCDD on NPC proliferation. We demonstrated that C17.2 NPCs express an intact AhR signaling pathway that becomes transcriptionally active after TCDD exposure. (3)H-thymidine and alamar blue reduction assays indicated that TCDD suppresses NPC proliferation in a concentration-dependent manner without the loss of cell viability. Cell cycle distribution analysis by flow cytometry revealed that TCDD-induced growth arrest results from an impaired G1 to S cell cycle transition. Moreover, TCDD exposure altered p27( kip1) and cyclin D1 cell cycle regulatory protein expression levels consistent with a G1 phase arrest. Initial studies in primary NPCs isolated from the ventral forebrain of embryonic mice demonstrated that TCDD reduced cell proliferation through a G1 phase arrest, corroborating our findings in the C17.2 cell line. Together, these observations suggest that the inappropriate or sustained activation of Ah

  16. T-cell effector function and unresponsiveness in the murine lymphocytic choriomeningitis virus infection. II. Delayed-type hypersensitivity unresponsiveness reflects a defective differentiation from TD precursor to effector cell

    DEFF Research Database (Denmark)

    Thomsen, Allan Randrup; Marker, O

    1986-01-01

    is markedly depressed in high-dose mice, suggesting an association between DTH and virus clearance. When virus-primed memory cells are transferred, DTH reactivity as well as virus-clearing capacity is restored in high-dose mice, indicating that the virus is not present in a changed or concealed form. The role...... transfer a DTH response emerged, indicating that TD priming had taken place in high-dose animals. Pre-irradiation of high-dose primed cells markedly inhibited the antiviral activity as well as DTH, suggesting that upon transfer to naive recipients TD precursors from high-dose mice would proliferate...... into effector cells capable of mediating both functions. Treatment with anti-Lyt2+C' abrogated the capacity to induce virus-specific DTH, thus confirming that the cells involved are not helper T (TH) cells. We conclude that the DTH unresponsiveness in high-dose mice reflects a defective differentiation of TD...

  17. Precursor B-Cell Acute Lymphoblastic Leukemia/Lymphoma with L3 Morphology, Philadelphia Chromosome, MYC Gene Translocation, and Coexpression of TdT and Surface Light Chains: A Case Report

    Directory of Open Access Journals (Sweden)

    Alicia C. Hirzel

    2013-01-01

    Full Text Available Acute lymphoblastic leukemia is predominantly found in children. It is a neoplasm of precursor cells or lymphoblasts committed to either a B- or T-cell lineage. The immature cells in B-acute lymphoblastic leukemia/lymphoma can be small or medium sized with scant or moderate cytoplasm and typically express B-cell markers such as CD19, cytoplasmic CD79a, and TdT without surface light chains. These markers, along with cytogenetic studies, are vital to the diagnosis, classification, and treatment of these neoplasms. We present an unusual case of a precursor B-cell ALL, in an 82-year-old woman, who presented with pancytopenia and widespread lymphadenopathy. The cells show L3 morphology (Burkitt-like lymphoma with coexpression of TdT and surface light chains in addition to an MYC gene translocation and Philadelphia chromosome.

  18. Effect of orientation and density of hydroxide precursor films on performance of dye-sensitized ZnO solar cells

    National Research Council Canada - National Science Library

    KAJIHARA, Hisasuke; HAGIWARA, Manabu; FUJIHARA, Shinobu

    2016-01-01

    .... The increase in the film density resulted in the improvement of the open-circuit voltage and the fill factor of dye-sensitized solar cells using N719-loaded ZnO films as photoanodes. The light-to-electricity conversion efficiency of 3.49% was obtained in the DSSC using the present ZnO film.

  19. Focal adhesion kinase activation is necessary for stretch-induced alignment and enhanced differentiation of myogenic precursor cells

    DEFF Research Database (Denmark)

    Andersen, Jens Isak; Pennisi, Cristian Pablo; Fink, Trine

    2017-01-01

    ), they display uniform alignment and an enhanced rate of differentiation. In this work, we explored the role of FAK activation by using C2C12 myoblasts that were grown on flexible culture plates and exposed to UCTS during the early differentiation phase. After 24 h, the cells oriented perpendicularly...

  20. Bone marrow precursors of nonobese diabetic mice develop into defective macrophage-like dendritic cells in vitro

    NARCIS (Netherlands)

    T. Nikolic (Tatjana); M. Bunk; H.A. Drexhage (Hemmo); P.J. Leenen (Pieter)

    2004-01-01

    textabstractThe NOD mouse spontaneously develops autoimmune diabetes. Dendritic cells (DC) play a crucial role in the autoimmune response. Previous studies have reported a defective DC generation in vitro from the NOD mouse bone marrow (BM), but a deviated development of myeloid

  1. Unspliced precursors of NMD-sensitive β-globin transcripts exhibit decreased steady-state levels in erythroid cells.

    Directory of Open Access Journals (Sweden)

    Ana Morgado

    Full Text Available Nonsense-mediated mRNA decay (NMD is a quality control mechanism that detects and rapidly degrades mRNAs carrying premature translation-termination codons (PTCs. Mammalian NMD depends on both splicing and translation, and requires recognition of the premature stop codon by the cytoplasmic ribosomes. Surprisingly, some published data have suggested that nonsense codons may also affect the nuclear metabolism of the nonsense-mutated transcripts. To determine if nonsense codons could influence nuclear events, we have directly assessed the steady-state levels of the unspliced transcripts of wild-type and PTC-containing human β-globin genes stably transfected in mouse erythroleukemia (MEL cells, after erythroid differentiation induction, or in HeLa cells. Our analyses by ribonuclease protection assays and reverse transcription-coupled quantitative PCR show that β-globin pre-mRNAs carrying NMD-competent PTCs, but not those containing a NMD-resistant PTC, exhibit a significant decrease in their steady-state levels relatively to the wild-type or to a missense-mutated β-globin pre-mRNA. On the contrary, in HeLa cells, human β-globin pre-mRNAs carrying NMD-competent PTCs accumulate at normal levels. Functional analyses of these pre-mRNAs in MEL cells demonstrate that their low steady-state levels do not reflect significantly lower pre-mRNA stabilities when compared to the normal control. Furthermore, our results also provide evidence that the relative splicing efficiencies of intron 1 and 2 are unaffected. This set of data highlights potential nuclear pathways that might be promoter- and/or cell line-specific, which recognize the NMD-sensitive transcripts as abnormal. These specialized nuclear pathway(s may be superimposed on the general NMD mechanism.

  2. Efficient Planar Structured Perovskite Solar Cells with Enhanced Open-Circuit Voltage and Suppressed Charge Recombination Based on a Slow Grown Perovskite Layer from Lead Acetate Precursor.

    Science.gov (United States)

    Li, Cong; Guo, Qiang; Wang, Zhibin; Bai, Yiming; Liu, Lin; Wang, Fuzhi; Zhou, Erjun; Hayat, Tasawar; Alsaedi, Ahmed; Tan, Zhan'ao

    2017-12-06

    For planar structured organic-inorganic hybrid perovskite solar cells (PerSCs) with the poly(3,4-ethylenedioxythiophene:polystyrene sulfonate) (PEDOT:PSS) hole transport layer, the open-circuit voltage (Voc) of the device is limited to be about 1.0 V, resulting in inferior performance in comparison with TiO2-based planar counterparts. Therefore, increasing Voc of the PEDOT:PSS-based planar device is an important way to enhance the efficiency of the PerSCs. Herein, we demonstrate a novel approach for perovskite film formation and the film is formed by slow growth from lead acetate precursor via a one-step spin-coating process without the thermal annealing (TA) process. Because the perovskite layer grows slowly and naturally, high-quality perovskite film can be achieved with larger crystalline particles, less defects, and smoother surface morphology. Ultraviolet absorption, X-ray diffraction, scanning electron microscopy, steady-state fluorescence spectroscopy (photoluminescence), and time-resolved fluorescence spectroscopy are used to clarify the crystallinity, morphology, and internal defects of perovskite thin films. The power conversion efficiency of p-i-n PerSCs based on slow-grown film (16.33%) shows greatly enhanced performance compared to that of the control device based on traditional thermally annealed perovskite film (14.33%). Furthermore, the Voc of the slow-growing device reaches 1.12 V, which is 0.1 V higher than that of the TA device. These findings indicate that slow growth of the perovskite layer from lead acetate precursor is a promising approach to achieve high-quality perovskite film for high-performance PerSCs.

  3. Human mesenchymal precursor cells (Stro-1⁺) from spinal cord injury patients improve functional recovery and tissue sparing in an acute spinal cord injury rat model.

    Science.gov (United States)

    Hodgetts, Stuart I; Simmons, Paul J; Plant, Giles W

    2013-01-01

    This study aimed to determine the potential of purified (Stro-1(+)) human mesenchymal precursor cells (hMPCs) to repair the injured spinal cord (SC) after transplantation into T-cell-deficient athymic RNU nude rats following acute moderate contusive spinal cord injury (SCI). hMPCs were isolated from the bone marrow (BM) stroma of SCI patients and transplanted as a suspension graft in medium [with or without immunosuppression using cyclosporin A (CsA)]. Extensive anatomical analysis shows statistically significant improvement in functional recovery, tissue sparing, and cyst reduction. We provide quantitative assessment of supraspinal projections in combination with functional outcomes. hMPC-transplanted animals consistently achieved mean BBB scores of 15 at 8 weeks post injury. Quantitative histological staining revealed that graft-recipient animals possessed more intact spinal tissue and reduced cyst formation than controls. Fluorogold (FG) retrograde tracing revealed sparing/regeneration of supraspinal and local propriospinal axonal pathways, but no statistical differences were observed compared to controls. Immunohistochemical analysis revealed increased serotonergic (5-HT) and sensory (CGRP) axonal growth within and surrounding transplanted donor hMPCs 2 weeks posttransplantation, but no evidence of hMPC transdifferentiation was seen. Although hMPCs initially survive at 2 weeks posttransplantation, their numbers were dramatically reduced and no cells were detected at 8 weeks posttransplantation using retroviral/lentiviral GFP labeling and a human nuclear antigen (HNA) antibody. Additional immunosuppression with CsA did not improve hMPC survival or their ability to promote tissue sparing or functional recovery. We propose Stro-1(+)-selected hMPCs provide (i) a reproducible source for stem cell transplantation for SC therapy and (ii) a positive host microenvironment resulting in the promotion of tissue sparing/repair that subsequently improves behavioral outcomes

  4. Selective elimination of marrow precursors with the bone-seeking isotope /sup 89/Sr: implications for hemopoiesis, lymphopoiesis, viral leukemogenesis, and infection

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, M.; Baker, E.E.; Eastcott, J.W.; Kumar, V.; Yonkosky, D.

    1976-07-01

    Radioactive strontium (/sup 89/Sr) is a bone-seeking isotope that becomes incorporated into bone and emits alpha particles, thus destroying hemopoietic cells within marrow cavities. Other hemopoietic tissues are spared and the spleen takes over all stem cell functions of the mouse. This procedure is effectively equivalent to a bone marrow-ectomy and the question can be asked: Do any particular cell types depend upon residence within the marrow for critical stages in their differentiation. Mice treated with /sup 89/Sr were able to generate Ab-forming cells and to reject skin allografts. These data indicated that stem cells from the spleen were able to differentiate into B cells in the bursa equivalent central lymphoid organ (which was obviously not the bone marrow), into T cells in the thymus, into monocyte/macrophage cells which function as accessory cells in humoral immunity and into effector cells in tissue allograft immunity. The effects of /sup 89/Sr administration on various T cell, B cell, and macrophage functions in mice were investigated. Most of the functions tested were normal and results of these investigations are presented in detail.

  5. Differential sensitivity of T lymphocytes and hematopoietic precursor cells to photochemotherapy with 8-methoxypsoralen and ultraviolet A light.

    Science.gov (United States)

    Mabed, Mohamed; Coffe, Christian; Racadot, Evelyne; Angonin, Regis; Pavey, Jean-Jaques; Tiberghien, Pierre; Herve, Patrick

    2006-01-01

    The combination of 8-methoxypsoralen (8-MOP) and long wave ultraviolet radiation (UV-A) has immunomodulatory effects and might abolish both graft-vs-host and host-vs-graft reactions after allogeneic hematopoietic stem cell transplantation. In the present study, we have confirmed the sensitivity of T lymphocytes to 8-MOP treatment plus UV-A exposure as evidenced by the abrogation of the alloreactivity in mixed lymphocyte cultures as well as the inhibition of the response to phytohemagglutinin A. However, the clonogenic capacity of the bone marrow hematopoietic progenitors was inhibited with UV-A doses lower than the doses needed to inhibit T-lymphocytes alloreactivity. Moreover, long-term bone marrow cultures showed that 8-MOP plus UV-A treatment had detrimental effects on the more immature bone marrow stem cells. These data were confirmed when murine bone marrow graft was treated with 8-MOP, exposed to UV-A, then transplanted into semiallogeneic recipient mice. The treated cells could not maintain their clonogenic capacity in vivo resulting in death of all animals. Taken together, these data show that ex vivo 8-MOP plus UV-A treatment of the marrow graft cannot be used to prevent post-bone marrow transplantation alloreactivity.

  6. Precursors and BRST symmetry

    Science.gov (United States)

    de Boer, Jan; Freivogel, Ben; Kabir, Laurens; Lokhande, Sagar F.

    2017-07-01

    In the AdS/CFT correspondence, bulk information appears to be encoded in the CFT in a redundant way. A local bulk field corresponds to many different non-local CFT operators (precursors). We recast this ambiguity in the language of BRST symmetry, and propose that in the large N limit, the difference between two precursors is a BRST exact and ghost-free term. This definition of precursor ambiguities has the advantage that it generalizes to any gauge theory. Using the BRST formalism and working in a simple model with global symmetries, we re-derive a precursor ambiguity appearing in earlier work. Finally, we show within this model that the obtained ambiguity has the right number of parameters to explain the freedom to localize precursors within different spatial regions of the boundary order by order in the large N expansion.

  7. The extracellular matrix, p53 and estrogen compete to regulate cell-surface Fas/Apo-1 suicide receptor expression in proliferating embryonic cerebral cortical precursors, and reciprocally, Fas-ligand modifies estrogen control of cell-cycle proteins

    Directory of Open Access Journals (Sweden)

    Newman Joseph M

    2004-03-01

    Full Text Available Abstract Background Apoptosis is important for normal cerebral cortical development. We previously showed that the Fas suicide receptor was expressed within the developing cerebral cortex, and that in vitro Fas activation resulted in caspase-dependent death. Alterations in cell-surface Fas expression may significantly influence cortical development. Therefore, in the following studies, we sought to identify developmentally relevant cell biological processes that regulate cell-surface Fas expression and reciprocal consequences of Fas receptor activation. Results Flow-cytometric analyses identified two distinct neural sub-populations that expressed Fas on their cell surface at high (FasHi or moderate (FasMod levels. The anti-apoptotic protein FLIP further delineated a subset of Fas-expressing cells with potential apoptosis-resistance. FasMod precursors were mainly in G0, while FasHi precursors were largely apoptotic. However, birth-date analysis indicated that neuroblasts express the highest levels of cell-surface Fas at the end of S-phase, or after their final round of mitosis, suggesting that Fas expression is induced at cell cycle checkpoints or during interkinetic nuclear movements. FasHi expression was associated with loss of cell-matrix adhesion and anoikis. Activation of the transcription factor p53 was associated with induction of Fas expression, while the gonadal hormone estrogen antagonistically suppressed cell-surface Fas expression. Estrogen also induced entry into S-phase and decreased the number of Fas-expressing neuroblasts that were apoptotic. Concurrent exposure to estrogen and to soluble Fas-ligand (sFasL suppressed p21/waf-1 and PCNA. In contrast, estrogen and sFasL, individually and together, induced cyclin-A expression, suggesting activation of compensatory survival mechanisms. Conclusions Embryonic cortical neuronal precursors are intrinsically heterogeneous with respect to Fas suicide-sensitivity. Competing intrinsic (p53

  8. Effect of immunization with polyvinylpyrrolidone on the counts of stromal precursor cells in bone marrow and spleen of CBA and CBA/N mice and cytokine gene expression in primary cultures of these cells.

    Science.gov (United States)

    Gorskaya, U F; Danilova, T A; Mezentzeva, M V; Shapoval, M M; Nesterenko, V G

    2012-05-01

    Injection of polyvinylpyrrolidone (synthetic type 2 T-independent antigen) stimulated the efficiency of clone-forming efficiency and the content of stromal precursor cells in CBA mice in the femoral bone marrow (almost 3-fold) and in the spleen (by 1.7 times) with the peak within 24 h and normalization by day 3 after immunization. The expression of IL-6, IL-8, and TNF-α genes in bone marrow and spleen cultures from immunized animals appeared on day 1 and disappeared on day 3. Hence, stimulation of stromal tissue in response to polyvinylpyrrolidone immunization was significantly less pronounced in comparison with immunization with S. typhimurium antigens. The counts of stromal precursor cells in these organs did not increase in CBA/N mice not responding to polyvinylpyrrolidone because they had no xid-mutation in Brutton's tyrosine kinase (Btk) gene, and the proinflammatory cytokine genes expression in primary cultures derived from these animals did not increase either. These data indicated that the degree of stromal tissue stimulation in immunized mice correlated with the immune response intensity. This indicated a close relationship between the stromal tissue and immune system. Stromal tissue seemed to be stimulated not only and not so much through the stromal cell Toll-like receptors, but mainly through interactions of immunocompetent and stromal cells, the former presumably playing the leading role in this process.

  9. An early thymic precursor phenotype predicts outcome exclusively in HOXA-overexpressing adult T-cell acute lymphoblastic leukemia: a Group for Research in Adult Acute Lymphoblastic Leukemia study.

    Science.gov (United States)

    Bond, Jonathan; Marchand, Tony; Touzart, Aurore; Cieslak, Agata; Trinquand, Amélie; Sutton, Laurent; Radford-Weiss, Isabelle; Lhermitte, Ludovic; Spicuglia, Salvatore; Dombret, Hervé; Macintyre, Elizabeth; Ifrah, Norbert; Hamel, Jean-François; Asnafi, Vahid

    2016-06-01

    Gene expression studies have consistently identified a HOXA-overexpressing cluster of T-cell acute lymphoblastic leukemias, but it is unclear whether these constitute a homogeneous clinical entity, and the biological consequences of HOXA overexpression have not been systematically examined. We characterized the biology and outcome of 55 HOXA-positive cases among 209 patients with adult T-cell acute lymphoblastic leukemia uniformly treated during the Group for Research on Adult Acute Lymphoblastic Leukemia (GRAALL)-2003 and -2005 studies. HOXA-positive patients had markedly higher rates of an early thymic precursor-like immunophenotype (40.8% versus 14.5%, P=0.0004), chemoresistance (59.3% versus 40.8%, P=0.026) and positivity for minimal residual disease (48.5% versus 23.5%, P=0.01) than the HOXA-negative group. These differences were due to particularly high frequencies of chemoresistant early thymic precursor-like acute lymphoblastic leukemia in HOXA-positive cases harboring fusion oncoproteins that transactivate HOXA Strikingly, the presence of an early thymic precursor-like immunophenotype was associated with marked outcome differences within the HOXA-positive group (5-year overall survival 31.2% in HOXA-positive early thymic precursor versus 66.7% in HOXA-positive non-early thymic precursor, P=0.03), but not in HOXA-negative cases (5-year overall survival 74.2% in HOXA-negative early thymic precursor versus 57.2% in HOXA-negative non-early thymic precursor, P=0.44). Multivariate analysis further revealed that HOXA positivity independently affected event-free survival (P=0.053) and relapse risk (P=0.039) of chemoresistant T-cell acute lymphoblastic leukemia. These results show that the underlying mechanism of HOXA deregulation dictates the clinico-biological phenotype, and that the negative prognosis of early thymic precursor acute lymphoblastic leukemia is exclusive to HOXA-positive patients, suggesting that early treatment intensification is currently

  10. The role of the N-methyl-D-aspartate receptor in the proliferation of adult hippocampal neural stem and precursor cells.

    Science.gov (United States)

    Taylor, Chanel J; He, RongQiao; Bartlett, Perry F

    2014-04-01

    New neurons are continuously generated from resident pools of neural stem and precursor cells (NSPCs) in the adult brain. There are multiple pathways through which adult neurogenesis is regulated, and here we review the role of the N-methyl-D-aspartate receptor (NMDAR) in regulating the proliferation of NSPCs in the adult hippocampus. Hippocampal-dependent learning tasks, enriched environments, running, and activity-dependent synaptic plasticity, all potently up-regulate hippocampal NSPC proliferation. We first consider the requirement of the NMDAR in activity-dependent synaptic plasticity, and the role the induction of synaptic plasticity has in regulating NSPCs and newborn neurons. We address how specific NMDAR agonists and antagonists modulate proliferation, both in vivo and in vitro, and then review the evidence supporting the hypothesis that NMDARs are present on NSPCs. We believe it is important to understand the mechanisms underlying the activation of adult neurogenesis, given the potential that endogenous stem cell populations have for repopulating the hippocampus with functional new neurons. In conditions such as age-related memory decline, neurodegeneration and psychiatric disease, mature neurons are lost or become defective; as such, stimulating adult neurogenesis may provide a therapeutic strategy to overcome these conditions.

  11. Cu{sub 2}ZnSnS{sub 4} solar cells prepared by sulfurization of sputtered ZnS/Sn/CuS precursors

    Energy Technology Data Exchange (ETDEWEB)

    Li, Zhi-Shan; Wang, Shu-Rong, E-mail: shrw88@aliyun.com; Jiang, Zhi; Yang, Min; Lu, Yi-Lei; Liu, Si-Jia; Zhao, Qi-Chen; Hao, Rui-Ting

    2016-12-01

    Cu{sub 2}ZnSnS{sub 4} (CZTS) thin films were grown on Mo-coated Soda-lime-glass (SLG) substrates by sulfurization of sputtered ZnS/Sn/CuS precursors at different temperatures i.e. 560 °C, 580 °C and 600 °C. The effects of sulfurization temperature on the quality of CZTS thin films and solar cells were investigated. The crystal structure, surface morphology, chemical composition, phase purity and surface roughness of CZTS thin films fabricated at different sulfurization temperatures were characterized by X Ray Diffraction (XRD), scanning electron microscopy (SEM) equipped with an energy dispersive spectrometer (EDS), Raman spectroscopy and atomic force microscope (AFM), respectively. The results show that all CZTS thin films exhibit a polycrystalline kesterite structure and preferred (112) orientation. For the sulfurization temperature of 580 °C, the obtained CZTS thin films are dense and flat with larger grain size. Meanwhile composition studying indicates that the fabricated CZTS with single phase is copper poor and zinc rich. Furthermore, the surface roughness of CZTS film is the lowest. Finally, the CZTS solar cells with the structure of SLG/Mo/CZTS/CdS/i-ZnO/ITO/Al were fabricated and demonstrated the best power conversion efficiency of 3.59% when used sulfurization temperature was 580 °C.

  12. Cu2ZnSnS4 solar cells prepared by sulfurization of sputtered ZnS/Sn/CuS precursors

    Science.gov (United States)

    Li, Zhi-Shan; Wang, Shu-Rong; Jiang, Zhi; Yang, Min; Lu, Yi-Lei; Liu, Si-Jia; Zhao, Qi-Chen; Hao, Rui-Ting

    2016-12-01

    Cu2ZnSnS4 (CZTS) thin films were grown on Mo-coated Soda-lime-glass (SLG) substrates by sulfurization of sputtered ZnS/Sn/CuS precursors at different temperatures i.e. 560 °C, 580 °C and 600 °C. The effects of sulfurization temperature on the quality of CZTS thin films and solar cells were investigated. The crystal structure, surface morphology, chemical composition, phase purity and surface roughness of CZTS thin films fabricated at different sulfurization temperatures were characterized by X Ray Diffraction (XRD), scanning electron microscopy (SEM) equipped with an energy dispersive spectrometer (EDS), Raman spectroscopy and atomic force microscope (AFM), respectively. The results show that all CZTS thin films exhibit a polycrystalline kesterite structure and preferred (112) orientation. For the sulfurization temperature of 580 °C, the obtained CZTS thin films are dense and flat with larger grain size. Meanwhile composition studying indicates that the fabricated CZTS with single phase is copper poor and zinc rich. Furthermore, the surface roughness of CZTS film is the lowest. Finally, the CZTS solar cells with the structure of SLG/Mo/CZTS/CdS/i-ZnO/ITO/Al were fabricated and demonstrated the best power conversion efficiency of 3.59% when used sulfurization temperature was 580 °C.

  13. Pyocyanin and its precursor phenazine-1-carboxylic acid increase IL-8 and intercellular adhesion molecule-1 expression in human airway epithelial cells by oxidant-dependent mechanisms.

    Science.gov (United States)

    Look, Dwight C; Stoll, Lynn L; Romig, Sara A; Humlicek, Alicia; Britigan, Bradley E; Denning, Gerene M

    2005-09-15

    Pseudomonas aeruginosa secretes numerous factors that alter host cell function and may contribute to disease pathogenesis. Among recognized virulence factors is the redox-active phenazine pyocyanin. We have recently demonstrated that the precursor for pyocyanin, phenazine-1-carboxylic acid (PCA), increases oxidant formation and alters gene expression in human airway epithelial cells. We report in this work that PCA and pyocyanin increase expression of ICAM-1 both in vivo and in vitro. Moreover, phenazines enhanced cytokine-dependent increases in IL-8 and ICAM-1. Antioxidant intervention studies indicated both similarities and differences between PCA and pyocyanin. The thiol antioxidant N-acetyl cysteine, extracellular catalase, and inducible NO synthase inhibitors inhibited ICAM-1 and IL-8 increases in response to both phenazines. However, pyocyanin was significantly more sensitive to N-acetylcysteine inhibition. Interestingly, hydroxyl radical scavengers inhibited the response to pyocyanin, but not to PCA. These studies suggest that P. aeruginosa phenazines coordinately up-regulate chemokines (IL-8) and adhesion molecules (ICAM-1) by mechanisms that are, at least in part, oxidant dependent. However, results indicate that the mechanisms by which PCA and pyocyanin exert their effects are not identical, and not all antioxidant interventions are equally effective in inhibiting phenazine-mediated proinflammatory effects.

  14. An in vitro study on the involvement of LINGO-1 and Rho GTPases in Nogo-A regulated differentiation of oligodendrocyte precursor cells.

    Science.gov (United States)

    Zhao, Xiang-Hui; Jin, Wei-Lin; Ju, Gong

    2007-10-01

    Nogo-A has been considered as one of the most important myelin-associated axonal regeneration inhibitors in the central nervous system. Recent studies have demonstrated various additional physiological roles of Nogo family members. To understand the possible effect of Nogo-A on the differentiation of oligodendrocytes, antibodies against distinct extracellular domains of Nogo-A were applied in cell cultures. Oligodendrocyte precursor cells from P2 rat cortex were grown in the presence of monoclonal antibody against the N-terminal inhibitory domain of Nogo-A or the C-terminal 66 amino acid loop of Nogo-A for 3 days, and the antibody treatment resulted in stunted process extension and inhibited differentiation of oligodendrocytes. Concomitant with morphology changes, Rho GTPases activity was greatly increased upon the antibody treatment and the expression level of LINGO-1, which was recently shown to be a negative regulator for the oligodendrocyte maturation, was upregulated in the process of antibody treatment. These results indicate that endogenous Nogo-A expressed in oligodendrocyte may act though Rho GTPase and LINGO-1 to influence the morphological differentiation of oligodendrocytes and will help us to understand the physiology role of Nogo-A in oligodendrocyte biology.

  15. Ocular manifestation in myeloid/NK cell precursor acute leukemia: a case report. Diagnosed by flow cytometry and PCR from aqueous humor.

    Science.gov (United States)

    Akaike, Sayaka; Kamoi, Koju; Tezuka, Mari; Tomizawa, Daisuke; Yoshimura, Ryoichi; Takagi, Masatoshi; Ohno-Matsui, Kyoko

    2016-09-01

    Myeloid/NK cell precursor acute leukemia (MNKL) is a rare type of leukemia, and ocular complications have not previously been reported. We now report a patient with MNKL who developed intraocular infiltrates during follow-up. A 13-year-old boy diagnosed with MNKL developed left eye pain 3 months after starting treatment. Examination of the left eye revealed a visual acuity of counting fingers at 20 cm, ciliary hyperemia, small corneal keratic precipitates, hypopyon, grade 4 vitreous opacities, and an obscured fundus. The differential diagnosis was between an opportunistic infection associated with immunodeficiency and an intraocular leukemic cell infiltrate. Therefore, a sample of aqueous humor was aspirated. Multiplex PCR/broad-range PCR of the aqueous humor was below detection limits for viruses, bacteria, and fungi. Flow cytometry (FCM) detected NK-related CD56-positive cells, thus leading to a diagnosis of ocular infiltrates due to MNKL. With treatment of the ocular infiltrates by consolidation systemic chemotherapy including intrathecal methotrexate (MTX), there was clearing of the vitreous opacities; and optic disc swelling, retinal hemorrhages, exudates, and protuberant lesions were now seen. With the addition of local radiation therapy to the eye, there was a dramatic treatment response, with regression of the optic disc findings and retinal lesions, and an improved visual acuity of 1.5. We encountered the first case of MNKL in which ocular infiltrates developed during follow-up. Multiplex PCR and FCM of the aqueous humor were useful in rapidly distinguishing leukemic cell infiltrates from an opportunistic infection. This case highlights the usefulness of intrathecal MTX and local radiotherapy in treating ocular infiltrates in patients with MNKL.

  16. A novel unbalanced de novo translocation der(5t(4;5(q26;q21.1 in adult T-cell precursor lymphoblastic leukemia

    Directory of Open Access Journals (Sweden)

    Kjeldsen Eigil

    2012-05-01

    Full Text Available Abstract We here describe a novel unbalanced de novo translocation der(5t(4;5(q26;q21.1 in a 39-year-old male diagnosed with acute T-cell lymphoblastic leukemia. Bone marrow (BM was massively infiltrated with 85 % highly proliferative polymorphic T-cell precursors. Immunologically, the malignant cells stained positive for CD7, CD34, intracytoplasmic CD3+, TdT + and negative for CD3 and CD5. G-banded chromosome analysis of BM cells showed the normal karyotype 46,XY[25] whereas BAC-based aCGH analysis revealed partial gain of 4q and partial loss of 5q. Multicolor karyotyping confirmed the presence of an unbalanced der(5t(4;5 as the sole structural abnormality. Subsequent high-resolution oligonucleotide-based aCGH analysis showed that the der(5t(4;5(q26;q21.1 resulted in partial trisomy of 4q26qter (117,719,015-190,613,014 and partial monosomy of 5q21.1qter (100,425,442-180,857,866 and that there was no indication of any gene disruptions resulting from the breakages. Interphase FISH analysis using BAC-based specific probes for 4q26 and 5q21.1 confirmed the breakpoints and revealed approximately 80 % abnormal cells accordingly. At 4q26 the MIR1973 gene is located centromeric to the breakpoint in the copy number neutral region and the TRAM1L1 gene is located within the gained region. At 5q21.1 the genes ST8SIA4 and MIR548p are located centromeric to the breakpoint and no known genes up to approximately 1 Mb telomeric to the breakpoint in the copy number loss region. Interestingly, only the gene ST8SIA4 at 5q21.1 have been implicated in T-cell regulation as it encodes one of the key enzymes for polysialysation of surface proteins on dendritic cells which are important regulators for T-cell proliferation. The der(5t(4;5 is thought to play a crucial role in the pathogenesis of acute T-ALL due to either gain of 4q, the loss of 5q, or deregulation of genes in proximity to the breakpoints.

  17. Paediatric B-cell precursor acute lymphoblastic leukaemia with t(1;19)(q23;p13): clinical and cytogenetic characteristics of 47 cases from the Nordic countries treated according to NOPHO protocols

    DEFF Research Database (Denmark)

    Andersen, Mette Klarskov; Autio, Kirsi; Barbany, Gisela

    2011-01-01

    The translocation t(1;19)(q23;p13)/der(19)t(1;19) is a risk stratifying aberration in childhood B-cell precursor acute lymphoblastic leukaemia (BCP ALL) in the Nordic countries. We have identified 47 children/adolescents with t(1;19)/der(19)t(1;19)-positive BCP ALL treated on two successive Nordi...

  18. Clinical and cytogenetic features of pediatric dic(9;20)(p13.2;q11.2)-positive B-cell precursor acute lymphoblastic leukemias: a Nordic series of 24 cases and review of the literature

    DEFF Research Database (Denmark)

    Forestier, Erik; Gauffin, Fredrika; Andersen, Mette K

    2008-01-01

    Although dic(9;20)(p13.2;q11.2) is a characteristic abnormality in childhood B-cell precursor acute lymphoblastic leukemias (BCP ALL), little is known about its clinical impact or the type and frequency of additional aberrations it may occur together with. We here review the clinical and cytogene...

  19. Aging alters bone-fat reciprocity by shifting in vivo mesenchymal precursor cell fate towards an adipogenic lineage.

    Science.gov (United States)

    Singh, Lakshman; Brennan, Tracy A; Russell, Elizabeth; Kim, Jung-Hoon; Chen, Qijun; Brad Johnson, F; Pignolo, Robert J

    2016-04-01

    Bone marrow derived mesenchymal progenitor cells (MPCs) play an important role in bone homeostasis. Age-related changes occur in bone resulting in a decrease in bone density and a relative increase in adipocity. Although in vitro studies suggest the existence of an age-related lineage switch between osteogenic and adipogenic fates, stem cell and microenvironmental contributions to this process have not been elucidated in vivo. In order to study the effects of MPC and microenvironmental aging on functional engraftment and lineage switching, transplantation studies were performed under non-myeloablative conditions in old recipients, with donor MPCs derived from young and old green fluorescent protein (GFP) transgenic mice. Robust engraftment by young MPCs or their progeny was observed in the marrow, bone-lining region and in the matrix of young recipients; however, significantly lower engraftment was seen at the same sites in old recipients transplanted with old MPCs. Differentiation of transplanted MPCs strongly favored adipogenesis over osteogenesis in old recipients irrespective of MPC donor age, suggesting that microenvironmental alterations that occur with in vivo aging are predominately responsible for MPC lineage switching. These data indicate that aging alters bone-fat reciprocity and differentiation of mesenchymal progenitors towards an adipogenic fate. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. SnHPO{sub 4}: a promising precursor for active material as negative electrode in Li-ion cells

    Energy Technology Data Exchange (ETDEWEB)

    Moubtassim, M.L.E.; Corredor, J.I.; Tirado, J.L.; Vicente, C.P. [Universidad de Cordoba (Spain). Laboratorio de Quimica Inorganica

    2001-07-01

    SnHPO{sub 4} was synthesized by precipitation and characterized by X-ray diffraction. The discharge curve of electrochemical cells using SnHPO{sub 4} as active cathode material and metallic lithium as anode showed a first reduction step at ca. 1.5 V. X-ray diffraction patterns of lithiated samples showed very weak bands ascribable to metallic tin. For the voltage values lower than 0.8 V the well-known Li-Sn alloy formation takes place. An intermediate step appears in the range from 1.2 to 0.8 V. The capacity retention is stabilized after 10 cycles at ca. 200 mA h/g. (author)

  1. Ferrocene-Modified Phospholipid: An Innovative Precursor for Redox-Triggered Drug Delivery Vesicles Selective to Cancer Cells.

    Science.gov (United States)

    Noyhouzer, Tomer; L'Homme, Chloé; Beaulieu, Isabelle; Mazurkiewicz, Stephanie; Kuss, Sabine; Kraatz, Heinz-Bernhard; Canesi, Sylvain; Mauzeroll, Janine

    2016-05-03

    Controlled payload release is one of the key elements in the creation of a reliable drug delivery system. We report the discovery of a drug delivery vessel able to transport chemotherapeutic agents to target cancer cells and selectively trigger their release using the electrochemical activity of a ferrocene-modified phospholipid. Supported by in vitro assays, the competitive advantages of this discovery are (i) the simple one step scalability of the synthetic process, (ii) the stable encapsulation of toxic drugs (doxorubicin) during transport, and (iii) the selective redox triggering of the liposomes to harness their cytotoxic payload at the cancer site. Specifically, the redox-modified giant unilamellar vesicle and liposomes were characterized using advanced methods such as scanning electrochemical microscopy (SECM), transmission electron microscopy (TEM), dynamic light scattering (DLS), and fluorescent imaging.

  2. A genome-wide screen for bacterial envelope biogenesis mutants identifies a novel factor involved in cell wall precursor metabolism.

    Directory of Open Access Journals (Sweden)

    Catherine Paradis-Bleau

    2014-01-01

    Full Text Available The cell envelope of Gram-negative bacteria is a formidable barrier that is difficult for antimicrobial drugs to penetrate. Thus, the list of treatments effective against these organisms is small and with the rise of new resistance mechanisms is shrinking rapidly. New therapies to treat Gram-negative bacterial infections are therefore sorely needed. This goal will be greatly aided by a detailed mechanistic understanding of envelope assembly. Although excellent progress in the identification of essential envelope biogenesis systems has been made in recent years, many aspects of the process remain to be elucidated. We therefore developed a simple, quantitative, and high-throughput assay for mutants with envelope biogenesis defects and used it to screen an ordered single-gene deletion library of Escherichia coli. The screen was robust and correctly identified numerous mutants known to be involved in envelope assembly. Importantly, the screen also implicated 102 genes of unknown function as encoding factors that likely impact envelope biogenesis. As a proof of principle, one of these factors, ElyC (YcbC, was characterized further and shown to play a critical role in the metabolism of the essential lipid carrier used for the biogenesis of cell wall and other bacterial surface polysaccharides. Further analysis of the function of ElyC and other hits identified in our screen is likely to uncover a wealth of new information about the biogenesis of the Gram-negative envelope and the vulnerabilities in the system suitable for drug targeting. Moreover, the screening assay described here should be readily adaptable to other organisms to study the biogenesis of different envelope architectures.

  3. High-stability Ti{sup 4+} precursor for the TiO{sub 2} compact layer of dye-sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Yi, Qinghua; Cong, Shan; Wang, Hao; Wang, Yun; Dai, Xiao; Zhao, Jie; Sun, Yinghui; Lou, Yanhui; Zou, Guifu, E-mail: zouguifu@suda.edu.cn

    2015-11-30

    Graphical abstract: - Highlights: • We developed an aqueous polymer-assisted deposition method to improve the chemical stability of the TiCl{sub 4} aqueous solution. • The Ti{sup 4+} is encapsulated by the polymer can maintain their initial performances for several months. • The film is dense, smooth and uniform, preparing by this method. • The power conversion efficiency of the DSSC based on P-TiO{sub 2} compact film is about 12.5% higher than that based on H-TiO{sub 2}. - Abstract: A compact layer (blocking layer) can effectively block the direct contact between the fluorine-doped tin oxide (FTO) glass substrate and electrolyte in dye-sensitized solar cells (DSSCs). The TiCl{sub 4} hydrolysis has been widely adopted for preparing the TiO{sub 2} compact layer (H-TiO{sub 2}). However, the TiCl{sub 4} aqueous solution is unstable for its high reactivity. To improve the chemical stability of TiCl{sub 4} aqueous solution, the Ti{sup 4+} is encapsulated by the polymer, polyethyleneimine (PEI). Experimentals show that the Ti-PEI precursor solution can maintain their initial performances for several months. The resulting TiO{sub 2} film (P-TiO{sub 2}) grown by the Ti-PEI precursor is dense, smooth and uniform without any visible and detectable cracks or voids. The P-TiO{sub 2} compact layer is even denser than the H-TiO{sub 2} compact layer, suggesting reducing the electron recombination and prolonging the electron lifetime in dye-sensitized solar cells. Indeed, the electron lifetime of the DSSC based on the P-TiO{sub 2} is 13.15 ms, which is longer than the 10.83 ms based on H-TiO{sub 2}. Meanwhile, the power conversion efficiency of the DSSC based on P-TiO{sub 2} compact film is about 12.5% higher than that based on H-TiO{sub 2}. Therefore, this encapsulation technology can not only improve the stability of the metal ions solution but also meet a large-scale fabrication demand of the TiO{sub 2} compact layer in future DSSCs.

  4. [Humoral regulation of stem cell proliferation].

    Science.gov (United States)

    Musashi, M; Ogawa, M

    1991-05-01

    The central feature of hematopoiesis is life-long, stable cell renewal. This process is supported by hemopoietic stem cells which, in the steady state, appear to be dormant in cell cycling. The recruitment of the dormant stem cells into cell cycle may be promoted by such factors as interleukin (IL)-1, IL-6, granulocyte-colony stimulating factor (G-CSF), and newly discovered IL-11. The effects of IL-1 on stem cells may be indirect. Once the stem cells leave Go and begin proliferation, the subsequent process is characterized by continued proliferation and differentiation. Though several models of stem cell differentiation have been proposed, micromanipulation studies of individual progenitors suggest that the commitment of multipotential progenitors to single lineages is a stochastic process. The proliferation of early hemopoietic progenitors requires the presence of IL-3 and/or IL-4, and the intermediate process appears to be supported by granulocyte/macrophage-CSF (GM-CSF). Once the progenitors are committed to individual lineages, the subsequent maturation process appears to be supported by late-acting, lineage-specific factors such as erythropoietin (erythropoiesis), G-CSF (neutrophil production), and IL-5 (eosinophilopoiesis). Thus, hemopoietic proliferation appears to be regulated by a cascade of factors directed at different developmental stages.

  5. Non-invasive Imaging and Tracking of Engineered Human Muscle Precursor Cells for Skeletal Muscle Tissue Engineering Using Positron Emission Tomography

    Science.gov (United States)

    Haralampieva, Deana; Betzel, Thomas; Dinulovic, Ivana; Salemi, Souzan; Stoelting, Meline; Kraemer, Stefanie; Schibli, Roger; Sulser, Tullio; Handschin, Christoph; Eberli, Daniel; Ametamey, Simon M.

    2016-01-01

    Transplantation of human muscle precursor cells (hMPCs) is envisioned for the treatment of various muscle diseases. However, a feasible non-invasive tool to monitor cell survival, migration and integration into the host tissue is still missing. Methods In this study, we designed an adenoviral delivery system to genetically modify hMPCs to express a signaling-deficient form of a human dopamine D2 receptor (hD2R). The gene expression levels of the receptor were evaluated by Reverse Transcriptase Polymerase Chain Reaction (RTPCR) and infection efficiency was visualized by fluorescent microscopy. Viability, proliferation and differentiation capacity of the transduced cells were confirmed and their sustained myogenic phenotype was shown by flow cytometry analysis and fluorescent microscopy. 18F-Fallypride and 18F-FMISO, two well-established PET radioligands, were successfully synthesized and evaluated for their potential to image engineered hMPCs in a mouse model. Furthermore, biodistribution studies and autoradiography were also performed to determine the extent of signal specificity. Results To address the feasibility of the presented approach for tracking of hMPCs in an in vivo model, we first evaluated the safety of the adenoviral gene-delivery, which showed no detrimental effects on the primary human cells. Specific binding of 18F-Fallypride to hD2R_hMPCs was demonstrated in vitro, as well as in vivo, by performing autoradiography, biodistribution and PET experiments, respectively. Furthermore, 18F-FMISO uptake was evaluated at different time-points after cell inoculation in vivo, showing high signal only at the early stages. Finally, histological assessment of the harvested tissues confirmed the sustained survival of the transplanted cells at different time-points with formation of muscle tissue at the site of injection. Conclusion We here propose a signaling-deficient human D2R as a potent reporter for in vivo hMPCs PET tracking by 18F-Fallypride. This approach

  6. Human fetal lymphoid tissue-inducer cells are interleukin 17-producing precursors to RORC(+) CD127(+) natural killer-like cells

    NARCIS (Netherlands)

    Cupedo, Tom; Crellin, Natasha K.; Papazian, Natalie; Rombouts, Elwin J.; Weijer, Kees; Grogan, Jane L.; Fibbe, Willem E.; Cornelissen, Jan J.; Spits, Hergen

    2009-01-01

    The human body contains over 500 individual lymph nodes, yet the biology of their formation is poorly understood. Here we identify human lymphoid tissue-inducer cells (LTi cells) as lineage-negative RORC(+) CD127(+) cells with the functional ability to interact with mesenchymal cells through

  7. CD20 up-regulation in pediatric B-cell precursor acute lymphoblastic leukemia during induction treatment: setting the stage for anti-CD20 directed immunotherapy

    Science.gov (United States)

    Schumich, Angela; Printz, Dieter; Pötschger, Ulrike; Husak, Zvenyslava; Attarbaschi, Andishe; Basso, Giuseppe; Gaipa, Giuseppe; Ratei, Richard; Mann, Georg; Gadner, Helmut

    2008-01-01

    CD20 is expressed in approximately one- half of pediatric acute lymphoblastic leukemia (ALL) cases with B-cell precursor (BCP) origin. We observed that it is occasionally up-regulated during treatment. To understand the impact of this on the potential effectiveness of anti-CD20 immunotherapy, we studied 237 CD10+ pediatric BCP-ALL patients with Berlin-Frankfurt-Munster (BFM)–type therapy. We analyzed CD20 expression changes from diagnosis to end-induction, focusing on sample pairs with more than or equal to 0.1% residual leukemic blasts, and assessed complement-induced cytotoxicity by CD20-targeting with rituximab in vitro. CD20-positivity significantly increased from 45% in initial samples to 81% at end-induction (day 15, 71%). The levels of expression also increased; 52% of cases at end-induction had at least 90% CD20pos leukemic cells, as opposed to 5% at diagnosis (day 15, 20%). CD20 up-regulation was frequent in high-risk patients, patients with high minimal residual disease at end-induction, and patients who suffered later from relapse, but not in TEL/AML1 cases. Notably, up-regulation occurred in viable cells sustaining chemotherapy. In vitro, CD20 up-regulation significantly enhanced rituximab cytotoxicity and could be elicited on prednisolone incubation. In conclusion, CD20 up-regulation is frequently induced in BCP-ALL during induction, and this translates into an acquired state of higher sensitivity to rituximab. This study was registered at http://www.clinicaltrials.gov as #NCT00430118. PMID:18780832

  8. The Na+/H+ exchanger NHE6 modulates endosomal pH to control processing of amyloid precursor protein in a cell culture model of Alzheimer disease.

    Science.gov (United States)

    Prasad, Hari; Rao, Rajini

    2015-02-27

    Early intervention may be key to safe and effective therapies in patients with Alzheimer disease. Endosomal dysfunction is an early step in neurodegeneration. Endosomes are a major site of production of Aβ peptide from the processing of amyloid precursor protein (APP) by clipping enzymes (β- and γ-secretases). The β-secretase enzyme BACE1 requires acidic lumen pH for optimum function, and acid pH promotes Aβ aggregation. The Na(+)/H(+) exchanger NHE6 provides a leak pathway for protons, limiting luminal acidification by proton pumps. Like APP, NHE6 expression was induced upon differentiation of SH-SY5Y neuroblastoma cells and localized to an endosomal compartment. Therefore, we investigated whether NHE6 expression altered APP localization and processing in a stably transfected cell culture model of human APP expression. We show that co-expression with NHE6 or treatment with the Na(+)/H(+) ionophore monensin shifted APP away from the trans-Golgi network into early and recycling endosomes in HEK293 cells. NHE6 alkalinized the endosomal lumen, similar to monensin, and significantly attenuated APP processing and Aβ secretion. In contrast, Aβ production was elevated upon NHE6 knockdown. We show that NHE6 transcript and protein levels are lowered in Alzheimer brains relative to control. These findings, taken together with emerging genetic evidence linking endosomal Na(+)/H(+) exchangers with Alzheimer disease, suggest that proton leak pathways may regulate Aβ generation and contribute to disease etiology. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  9. Ex Vivo Mesenchymal Precursor Cell-Expanded Cord Blood Transplantation after Reduced-Intensity Conditioning Regimens Improves Time to Neutrophil Recovery.

    Science.gov (United States)

    Mehta, Rohtesh S; Saliba, Rima M; Cao, Kai; Kaur, Indreshpal; Rezvani, Katy; Chen, Julianne; Olson, Amanda; Parmar, Simrit; Shah, Nina; Marin, David; Alousi, Amin; Hosing, Chitra; Popat, Uday; Kebriaei, Partow; Champlin, Richard; de Lima, Marcos; Skerrett, Donna; Burke, Elizabeth; Shpall, Elizabeth J; Oran, Betul

    2017-08-01

    We previously showed the safety of using cord blood (CB) expanded ex vivo in cocultures with allogeneic mesenchymal precursor cells (MPC) after myeloablative conditioning with faster recovery of neutrophils and platelets compared with historical controls. Herein, we report the transplantation outcomes of 27 patients with hematologic cancers who received 1 CB unit expanded ex vivo with MPCs in addition to an unmanipulated CB (MPC group) after reduced-intensity conditioning (RIC). The results in this group were compared with 51 historical controls who received 2 unmanipulated CB units (control group). The analyses were stratified for 2 RIC treatment groups: (1) total body irradiation 200 cGy + cyclophosphamide + fludarabine) (TCF), and (2) fludarabine + melphalan  (FM). Coculture of CB with MPCs led to an expansion of total nucleated cells by a median factor of 12 and of CD34(+) cells by a median factor of 49. In patients in whom engraftment occurred, the median time to neutrophil engraftment was 12 days in the MPC group, as compared with 16 days in controls (P = .02). The faster neutrophil engraftment was observed in both RIC groups. The cumulative incidence of neutrophil engraftment on day 26 was 75% with expansion versus 50% without expansion in patients who received FM as the RIC regimen (P = .03). Incidence of neutrophil engraftment was comparable in MPC and control groups if treated with TCF (82% versus 79%, P = .40). Transplantation of CB units expanded with MPCs is safe and effective with faster neutrophil engraftment even after RIC regimens. Copyright © 2017. Published by Elsevier Inc.

  10. IKAP deficiency in an FD mouse model and in oligodendrocyte precursor cells results in downregulation of genes involved in oligodendrocyte differentiation and myelin formation.

    Science.gov (United States)

    Cheishvili, David; Dietrich, Paula; Maayan, Channa; Even, Aviel; Weil, Miguel; Dragatsis, Ioannis; Razin, Aharon

    2014-01-01

    The splice site mutation in the IKBKAP gene coding for IKAP protein leads to the tissue-specific skipping of exon 20, with concomitant reduction in IKAP protein production. This causes the neurodevelopmental, autosomal-recessive genetic disorder - Familial Dysautonomia (FD). The molecular hallmark of FD is the severe reduction of IKAP protein in the nervous system that is believed to be the main reason for the devastating symptoms of this disease. Our recent studies showed that in the brain of two FD patients, genes linked to oligodendrocyte differentiation and/or myelin formation are significantly downregulated, implicating IKAP in the process of myelination. However, due to the scarcity of FD patient tissues, these results awaited further validation in other models. Recently, two FD mouse models that faithfully recapitulate FD were generated, with two types of mutations resulting in severely low levels of IKAP expression. Here we demonstrate that IKAP deficiency in these FD mouse models affects a similar set of genes as in FD patients' brains. In addition, we identified two new IKAP target genes involved in oligodendrocyte cells differentiation and myelination, further underscoring the essential role of IKAP in this process. We also provide proof that IKAP expression is needed cell-autonomously for the regulation of expression of genes involved in myelin formation since knockdown of IKAP in the Oli-neu oligodendrocyte precursor cell line results in similar deficiencies. Further analyses of these two experimental models will compensate for the lack of human postmortem tissues and will advance our understanding of the role of IKAP in myelination and the disease pathology.

  11. Behavior of Electrochemically Prepared CuInSe{sub 2} as Photovoltaic Absorber in thin Film Solar Cells; Comportamiento del CuInSe{sub 2} Basado en Precursores Electrodepositados como Absorbente Fotovoltaico en Celulas Solares de Lamina Delgada

    Energy Technology Data Exchange (ETDEWEB)

    Guillen, C.; Martinez, M. A.; Dona, J. M.; Herrero, J.; Gutierrez, M. T. [Ciemat.Madrid (Spain)

    2000-07-01

    Two different objective have been pursued in the present investigation: (1) optimization of the CuInSe{sub 2} preparation parameters from electrodeposited precursors, and (2) evaluation of their photovoltaic behavior by preparing and enhancing Mo/CuInSe{sub 2}/CdS/TCO devices. When Cu-In-Se precursors are directly electrodeposited, the applied potential fit is essential to improve the photovoltaic performance. Suitable absorbers have been also obtained by evaporing an In layer onto electrodeposited Cu-Se precursors. In this case, the substrate temperature during evaporation determines the CuInSe{sub 2} quality. Similar results have been reached by substituting typical Mo-Coated glass substrates by flexible Mo foils. Different TCO tested (ZnO and ITO) have been found equivalent as front electrical contact in the devices. Solar cell performance can be improved by annealing in air at 200 degree centigree. (Author) 46 refs.

  12. Effect of the nature of cationic precursors for SILAR deposition on the performance of CdS and PbS/CdS quantum dot-sensitized solar cells

    Science.gov (United States)

    Liu, Yingbo; Li, Zhen; Yu, Libo; Sun, Shuqing

    2015-03-01

    In this work, the influences of cationic precursors on the quality of photoelectrode, consequently on the performance of the quantum dot-sensitized solar cells (QDSCs) have been studied. CdS QDSCs have been prepared using successive ionic layer absorption and reaction (SILAR) method. Three cadmium precursors including nitrate (Cd(NO3)2), chloride (CdCl2), and acetate (Cd(Ac)2) were employed for the synthesis and absorption of CdS nanoparticles on nanostructure TiO2 film. The loading amount and nanoparticle size of the CdS on mesoporous TiO2 film showed a significant difference while using various cadmium precursors in the same SILAR cycles. Both the light-harvesting ability and the obtained incident photon-to-current conversion efficiency values show the trend of deposition rate caused by cadmium precursors. Further, it was proposed that an effective cationic precursor could provide a good connection between QD sensitizer and TiO2 interface by electrochemical impedance spectroscopy analysis. Under AM 1.5 G full one sun illumination, the final power conversion efficiency of CdS QDSC based on Cd(Ac)2 was 2.10 %, and PCE values of 1.57 and 1.20 % were obtained for solar cells sensitized by CdS QDs prepared by CdCl2 and Cd(NO3)2, respectively. The cationic precursor effect was further applied in PbS/CdS co-sensitized solar cells. The PbS/CdS QDSCs based on acetate cationic precursors provide a photocurrent of 19.24 mA/cm2 and PCE of 3.23 % in comparison with 11.26 mA and 2.13 % obtained with nitrate acetate salts. Noticeably, the CdS and PbS/CdS QDSCs based on various cationic precursors prepared by SILAR exhibited good photocurrent stability under several light on-off cycles.

  13. Synthesis and structures of metal chalcogenide precursors

    Science.gov (United States)

    Hepp, Aloysius F.; Duraj, Stan A.; Eckles, William E.; Andras, Maria T.

    1990-01-01

    The reactivity of early transition metal sandwich complexes with sulfur-rich molecules such as dithiocarboxylic acids was studied. Researchers recently initiated work on precursors to CuInSe2 and related chalcopyrite semiconductors. Th every high radiation tolerance and the high absorption coefficient of CuInSe2 makes this material extremely attractive for lightweight space solar cells. Their general approach in early transition metal chemistry, the reaction of low-valent metal complexes or metal powders with sulfur and selenium rich compounds, was extended to the synthesis of chalcopyrite precursors. Here, the researchers describe synthesis, structures, and and routes to single molecule precursors to metal chalcogenides.

  14. Earthquakes: hydrogeochemical precursors

    Science.gov (United States)

    Ingebritsen, Steven E.; Manga, Michael

    2014-01-01

    Earthquake prediction is a long-sought goal. Changes in groundwater chemistry before earthquakes in Iceland highlight a potential hydrogeochemical precursor, but such signals must be evaluated in the context of long-term, multiparametric data sets.

  15. SNP association mapping across the extended major histocompatibility complex and risk of B-cell precursor acute lymphoblastic leukemia in children.

    Directory of Open Access Journals (Sweden)

    Kevin Y Urayama

    Full Text Available The extended major histocompatibility complex (xMHC is the most gene-dense region of the genome and harbors a disproportionately large number of genes involved in immune function. The postulated role of infection in the causation of childhood B-cell precursor acute lymphoblastic leukemia (BCP-ALL suggests that the xMHC may make an important contribution to the risk of this disease. We conducted association mapping across an approximately 4 megabase region of the xMHC using a validated panel of single nucleotide polymorphisms (SNPs in childhood BCP-ALL cases (n=567 enrolled in the Northern California Childhood Leukemia Study (NCCLS compared with population controls (n=892. Logistic regression analyses of 1,145 SNPs, adjusted for age, sex, and Hispanic ethnicity indicated potential associations between several SNPs and childhood BCP-ALL. After accounting for multiple comparisons, one of these included a statistically significant increased risk associated with rs9296068 (OR=1.40, 95% CI=1.19-1.66, corrected p=0.036, located in proximity to HLA-DOA. Sliding window haplotype analysis identified an additional locus located in the extended class I region in proximity to TRIM27 tagged by a haplotype comprising rs1237485, rs3118361, and rs2032502 (corrected global p=0.046. Our findings suggest that susceptibility to childhood BCP-ALL is influenced by genetic variation within the xMHC and indicate at least two important regions for future evaluation.

  16. Investigation of selenization process of electrodeposited Cu–Zn–Sn precursor for Cu{sub 2}ZnSnSe{sub 4} thin-film solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Kondrotas, R., E-mail: rokas.kondrotas@ftmc.lt [State Research Institute Centre for Physical Sciences and Technology, Chemistry Institute, Savanoriu ave. 231, Vilnius (Lithuania); Juškėnas, R.; Naujokaitis, A.; Niaura, G.; Mockus, Z.; Kanapeckaitė, S. [State Research Institute Centre for Physical Sciences and Technology, Chemistry Institute, Savanoriu ave. 231, Vilnius (Lithuania); Čechavičius, B. [State Research Institute Centre for Physical Sciences and Technology, Semiconductor Physics Institute, Savanoriu ave. 231, Vilnius Lithuania (Lithuania); Juškevičius, K. [State Research Institute Centre for Physical Sciences and Technology, Physics Institute, Savanoriu ave. 231, Vilnius (Lithuania); Saucedo, E.; Sánchez, Y. [Catalonia Institute for Energy Research (IREC), Jardins de les dones de negre 1, Sant Adrià de Besòs, Barcelona (Spain)

    2015-08-31

    In this study we present the investigation of Cu{sub 2}ZnSnSe{sub 4} (CZTSe) absorber layers formed using electrochemical co-deposition in the stirred citrate solution. Two different Mo back contacts were tested to evaluate the formation of MoSe{sub 2} during selenization of electrodeposited Cu–Zn–Sn (CZT) precursor. Cleaved and focused ion beam made cross-sections of CZT/Mo and CZTSe/MoSe{sub 2}/Mo layers and surface morphology of CZTSe were studied by scanning microscopy. The chemical composition was determined by x-ray energy dispersive and fluorescence spectroscopy, whereas phase composition was examined by x-ray diffraction and Raman spectroscopy. The formation of MoSe{sub 2} strongly depended on the microstructure of Mo and annealing conditions. Possible reasons for different selenization of Mo back contacts used were discussed. Photoluminescence (PL) measurements revealed that characteristics of CZTSe main PL peak were compositional dependent. The highest CZTSe solar cell efficiency obtained was 2.64%. - Highlights: • The thickness of MoSe{sub 2} of home-made Mo substrate was constant. • Center of photoluminescence peak was dependent on Cu{sub 2}ZnSnSe{sub 4} composition. • Poor quality of Mo/Cu{sub 2}ZnSnSe{sub 4} interface resulted in low shunt resistance.

  17. The Influence of Water Vapor on the Stability and Processing of Hybrid Perovskite Solar Cells Made from Non-Stoichiometric Precursor Mixtures.

    Science.gov (United States)

    Petrus, Michiel L; Hu, Yinghong; Moia, Davide; Calado, Philip; Leguy, Aurélien M A; Barnes, Piers R F; Docampo, Pablo

    2016-09-22

    We investigated the influence of moisture on methylammonium lead iodide perovskite (MAPbI 3 ) films and solar cells derived from non-stoichiometric precursor mixtures. We followed both the structural changes under controlled air humidity through in situ X-ray diffraction, and the electronic behavior of devices prepared from these films. A small PbI 2 excess in the films improved the stability of the perovskite compared to stoichiometric samples. We assign this to excess PbI 2 layers at the perovskite grain boundaries or to the termination of the perovskite crystals with Pb and I. In contrast, the MAI-excess films composed of smaller perovskite crystals showed increased electronic disorder and reduced device performance owing to poor charge collection. Upon exposure to moisture followed by dehydration (so-called solvent annealing), these films recrystallized to form larger, highly oriented crystals with fewer electronic defects and a remarkable improvement in photocurrent and photovoltaic efficiency. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Systemic Central Nervous System (CNS)-targeted Delivery of Neuropeptide Y (NPY) Reduces Neurodegeneration and Increases Neural Precursor Cell Proliferation in a Mouse Model of Alzheimer Disease.

    Science.gov (United States)

    Spencer, Brian; Potkar, Rewati; Metcalf, Jeff; Thrin, Ivy; Adame, Anthony; Rockenstein, Edward; Masliah, Eliezer

    2016-01-22

    Neuropeptide Y (NPY) is one of the most abundant protein transmitters in the central nervous system with roles in a variety of biological functions including: food intake, cardiovascular regulation, cognition, seizure activity, circadian rhythms, and neurogenesis. Reduced NPY and NPY receptor expression is associated with numerous neurodegenerative disorders including Alzheimer disease (AD). To determine whether replacement of NPY could ameliorate some of the neurodegenerative and behavioral pathology associated with AD, we generated a lentiviral vector expressing NPY fused to a brain transport peptide (apoB) for widespread CNS delivery in an APP-transgenic (tg) mouse model of AD. The recombinant NPY-apoB effectively reversed neurodegenerative pathology and behavioral deficits although it had no effect on accumulation of Aβ. The subgranular zone of the hippocampus showed a significant increase in proliferation of neural precursor cells without further differentiation into neurons. The neuroprotective and neurogenic effects of NPY-apoB appeared to involve signaling via ERK and Akt through the NPY R1 and NPY R2 receptors. Thus, widespread CNS-targeted delivery of NPY appears to be effective at reversing the neuronal and glial pathology associated with Aβ accumulation while also increasing NPC proliferation. Overall, increased delivery of NPY to the CNS for AD might be an effective therapy especially if combined with an anti-Aβ therapeutic. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  19. Pituitary adenylate cyclase-activating polypeptide stimulates glial fibrillary acidic protein gene expression in cortical precursor cells by activating Ras and Rap1.

    Science.gov (United States)

    Lastres-Becker, Isabel; Fernández-Pérez, Antonio; Cebolla, Beatriz; Vallejo, Mario

    2008-11-01

    Pituitary adenylate cyclase-activating polypeptide (PACAP) acts on cortical precursor cells to trigger glial fibrillary acidic protein (GFAP) gene expression and astrocyte differentiation by stimulation of intracellular cAMP production. Here, we show that as expected, PACAP activates cAMP-dependent protein kinase A. However, inhibition of protein kinase A does not prevent PACAP-induced GFAP gene expression or astrocytogenesis. PACAP also activates the small GTPases Rap1 and Ras, but either activation of Rap1 alone by selective stimulation of the guanine nucleotide exchange factor Epac, or expression of a constitutively active form of Ras, do not induce GFAP gene expression. Ras is activated by PACAP in a cAMP-dependent manner, and inhibition of Ras and/or Rap1 decreases PACAP-induced GFAP promoter stimulation. Thus, cAMP-dependent PACAP-induced GFAP expression during astrocytogenesis involves the coordinated activation of both Ras and Rap1, but activation of either one of them in isolation is not sufficient to trigger this response.

  20. Potential for Cell-Transplant Therapy with Human Neuronal Precursors to Treat Neuropathic Pain in Models of PNS and CNS Injury: Comparison of hNT2.17 and hNT2.19 Cell Lines

    Directory of Open Access Journals (Sweden)

    Mary J. Eaton

    2012-01-01

    Full Text Available Effective treatment of sensory neuropathies in peripheral neuropathies and spinal cord injury (SCI is one of the most difficult problems in modern clinical practice. Cell therapy to release antinociceptive agents near the injured spinal cord is a logical next step in the development of treatment modalities. But few clinical trials, especially for chronic pain, have tested the potential of transplant of cells to treat chronic pain. Cell lines derived from the human neuronal NT2 cell line parentage, the hNT2.17 and hNT2.19 lines, which synthesize and release the neurotransmitters gamma-aminobutyric acid (GABA and serotonin (5HT, respectively, have been used to evaluate the potential of cell-based release of antinociceptive agents near the lumbar dorsal (horn spinal sensory cell centers to relieve neuropathic pain after PNS (partial nerve and diabetes-related injury and CNS (spinal cord injury damage in rat models. Both cell lines transplants potently and permanently reverse behavioral hypersensitivity without inducing tumors or other complications after grafting. Functioning as cellular minipumps for antinociception, human neuronal precursors, like these NT2-derived cell lines, would likely provide a useful adjuvant or replacement for current pharmacological treatments for neuropathic pain.

  1. Blastic plasmacytoid dendritic cell neoplasm with leukemic manifestation and ETV6 gene rearrangement: A case report.

    Science.gov (United States)

    Gao, N A; Wang, Xue-Xia; Sun, Jian-Rong; Yu, Wen-Zheng; Guo, Nong-Jian

    2015-04-01

    Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare malignant tumor of the hemopoietic system that arises from plasmacytoid dendritic cell precursors with a highly aggressive course. BPDCN frequently involves the skin, lymph nodes, peripheral blood and bone marrow. BPDCN is known to develop leukemic dissemination as a feature of myelomonocytic leukemia in the late phase of the disease, which leads to a poorer prognosis. In the present study, a case of BPDCN with leukemic manifestation without cutaneous involvement was reported. In addition, ETS variant gene 6 (ETV6) gene rearrangement was detected in the patient. The patient relapsed soon after complete remisson and had no response to further treatment. To the best of our knowledge, this is the first reported case of BPDCN with ETV6 rearrangement. Following chemotherapy treatment, the patient suffered from severe headache in the complete remission stage; however, brain CT scans showed no significant abnormalities. Several lumbar punctures and intrathecal chemotherapy were performed, and the patient recovered gradually. Therefore, the patient was considered to suffer from central nervous system leukemia. In conclusion, implementation of lumbar punctures and preventive intrathecal chemotherapy are required in BPDCN patients with leukemic manifestation during the remission stage.

  2. Critical role of astrocytic interleukin-17 A in post-stroke survival and neuronal differentiation of neural precursor cells in adult mice

    Science.gov (United States)

    Lin, Y; Zhang, J-C; Yao, C-Y; Wu, Y; Abdelgawad, A F; Yao, S-L; Yuan, S-Y

    2016-01-01

    The brain and the immune system interact in complex ways after ischemic stroke, and the long-term effects of immune response associated with stroke remain controversial. As a linkage between innate and adaptive immunity, interleukin-17 A (IL-17 A) secreted from gamma delta (γδ) T cells has detrimental roles in the pathogenesis of acute ischemic stroke. However, to date, the long-term actions of IL-17 A after stroke have not been investigated. Here, we found that IL-17 A showed two distinct peaks of expression in the ischemic hemisphere: the first occurring within 3 days and the second on day 28 after stroke. Our data also showed that astrocyte was the major cellular source of IL-17 A that maintained and augmented subventricular zone (SVZ) neural precursor cells (NPCs) survival, neuronal differentiation, and subsequent synaptogenesis and functional recovery after stroke. IL-17 A also promoted neuronal differentiation in cultured NPCs from the ischemic SVZ. Furthermore, our in vitro data revealed that in primary astrocyte cultures activated astrocytes released IL-17 A via p38 mitogen-activated protein kinase (MAPK). Culture media from reactive astrocytes increased neuronal differentiation of NSCs in vitro. Blockade of IL-17 A with neutralizing antibody prevented this effect. In addition, after screening for multiple signaling pathways, we revealed that the p38 MAPK/calpain 1 signaling pathway was involved in IL-17 A-mediated neurogenesis in vivo and in vitro. Thus, our results reveal a previously uncharacterized property of astrocytic IL-17 A in the maintenance and augment of survival and neuronal differentiation of NPCs, and subsequent synaptogenesis and spontaneous recovery after ischemic stroke. PMID:27336717

  3. Early T-cell precursor acute lymphoblastic leukemia/lymphoma (ETP-ALL/LBL) in adolescents and adults: a high-risk subtype.

    Science.gov (United States)

    Jain, Nitin; Lamb, Audrey V; O'Brien, Susan; Ravandi, Farhad; Konopleva, Marina; Jabbour, Elias; Zuo, Zhuang; Jorgensen, Jeffrey; Lin, Pei; Pierce, Sherry; Thomas, Deborah; Rytting, Michael; Borthakur, Gautam; Kadia, Tapan; Cortes, Jorge; Kantarjian, Hagop M; Khoury, Joseph D

    2016-04-14

    Early T-cell precursor (ETP) acute lymphoblastic leukemia/lymphoma (ALL/LBL) is a recently recognized high-risk T lymphoblastic leukemia/lymphoma (T-ALL/LBL) subgroup. The optimal therapeutic approaches to adult patients with ETP-ALL/LBL are poorly characterized. In this study, we compared the outcomes of adults with ETP-ALL/LBL who received treatment on frontline regimens with those of patients with other T-ALL/LBL immunophenotypic subtypes. Patients with newly diagnosed T-ALL/LBL who received frontline chemotherapy between the years 2000 and 2014 at The University of Texas MD Anderson Cancer Center were identified and immunophenotypically categorized into early, thymic, and mature per the World Health Organization (WHO) classification using CD1a and surface CD3 status. Patients with ETP-ALL/LBL were identified on the basis of the following immunophenotypes: CD1a(-), CD8(-), CD5(-)(dim), and positivity for 1 or more stem cell or myeloid antigens. A total of 111 patients with T-ALL/LBL (68% T-ALL; 32% T-LBL) with adequate immunophenotype data were identified. The median age was 30 years (range, 13-79). There was no difference in the outcomes of patients based on the WHO subtypes. Nineteen patients (17%) had ETP-ALL/LBL. The complete remission rate /complete remission with incomplete platelet recovery rate in patients with ETP-ALL/LBL was significantly lower than that of non-ETP-ALL/LBL patients (73% vs 91%;P= .03). The median overall survival for patients with ETP-ALL/LBL was 20 months vs not reached for the non-ETP-ALL/LBL patients (P= .008). ETP-ALL/LBL represents a high-risk disease subtype of adult ALL. Novel treatment strategies are needed to improve treatment outcomes in this T-ALL/LBL subset. © 2016 by The American Society of Hematology.

  4. Use of plankton-derived vitamin B1 precursors, especially thiazole-related precursor, by key marine picoeukaryotic phytoplankton.

    Science.gov (United States)

    Paerl, Ryan W; Bouget, Francois-Yves; Lozano, Jean-Claude; Vergé, Valérie; Schatt, Philippe; Allen, Eric E; Palenik, Brian; Azam, Farooq

    2017-03-01

    Several cosmopolitan marine picoeukaryotic phytoplankton are B1 auxotrophs requiring exogenous vitamin B1 or precursor to survive. From genomic evidence, representatives of picoeukaryotic phytoplankton (Ostreococcus and Micromonas spp.) were predicted to use known thiazole and pyrimidine B1 precursors to meet their B1 demands, however, recent culture-based experiments could not confirm this assumption. We hypothesized these phytoplankton strains could grow on precursors alone, but required a thiazole-related precursor other the well-known and extensively tested 4-methyl-5-thiazoleethanol. This hypothesis was tested using bioassays and co-cultures of picoeukaryotic phytoplankton and bacteria. We found that specific B1-synthesizing proteobacteria and phytoplankton are sources of a yet-to-be chemically identified thiazole-related precursor(s) that, along with pyrimidine B1 precursor 4-amino-5-hydroxymethyl-2-methylpyrimidine, can support growth of Ostreococcus spp. (also Micromonas spp.) without B1. We additionally found that the B1-synthesizing plankton do not require contact with picoeukaryotic phytoplankton cells to produce thiazole-related precursor(s). Experiments with wild-type and genetically engineered Ostreococcus lines revealed that the thiazole kinase, ThiM, is required for growth on precursors, and that thiazole-related precursor(s) accumulate to appreciable levels in the euphotic ocean. Overall, our results point to thiazole-related B1 precursors as important micronutrients promoting the survival of abundant phytoplankton influencing surface ocean production and biogeochemical cycling.

  5. Circulating precursor CCR7(lo)PD-1(hi) CXCR5⁺ CD4⁺ T cells indicate Tfh cell activity and promote antibody responses upon antigen reexposure.

    Science.gov (United States)

    He, Jing; Tsai, Louis M; Leong, Yew Ann; Hu, Xin; Ma, Cindy S; Chevalier, Nina; Sun, Xiaolin; Vandenberg, Kirsten; Rockman, Steve; Ding, Yan; Zhu, Lei; Wei, Wei; Wang, Changqi; Karnowski, Alexander; Belz, Gabrielle T; Ghali, Joanna R; Cook, Matthew C; Riminton, D Sean; Veillette, André; Schwartzberg, Pamela L; Mackay, Fabienne; Brink, Robert; Tangye, Stuart G; Vinuesa, Carola G; Mackay, Charles R; Li, Zhanguo; Yu, Di

    2013-10-17

    Follicular B helper T (Tfh) cells support high affinity and long-term antibody responses. Here we found that within circulating CXCR5⁺ CD4⁺ T cells in humans and mice, the CCR7(lo)PD-1(hi) subset has a partial Tfh effector phenotype, whereas CCR7(hi)PD-1(lo) cells have a resting phenotype. The circulating CCR7(lo)PD-1(hi) subset was indicative of active Tfh differentiation in lymphoid organs and correlated with clinical indices in autoimmune diseases. Thus the CCR7(lo)PD-1(hi) subset provides a biomarker to monitor protective antibody responses during infection or vaccination and pathogenic antibody responses in autoimmune diseases. Differentiation of both CCR7(hi)PD-1(lo) and CCR7(lo)PD-1(hi) subsets required ICOS and BCL6, but not SAP, suggesting that circulating CXCR5⁺ helper T cells are primarily generated before germinal centers. Upon antigen reencounter, CCR7(lo)PD-1(hi) CXCR5⁺ precursors rapidly differentiate into mature Tfh cells to promote antibody responses. Therefore, circulating CCR7(lo)PD-1(hi) CXCR5⁺ CD4⁺ T cells are generated during active Tfh differentiation and represent a new mechanism of immunological early memory. Copyright © 2013 Elsevier Inc. All rights reserved.

  6. Temperature-dependent modification of muscle precursor cell behaviour is an underlying reason for lasting effects on muscle cellularity and body growth of teleost fish.

    Science.gov (United States)

    Steinbacher, Peter; Marschallinger, Julia; Obermayer, Astrid; Neuhofer, Alois; Sänger, Alexandra M; Stoiber, Walter

    2011-06-01

    Temperature is an important factor influencing teleost muscle growth, including a lasting ('imprinted') influence of embryonic thermal experience throughout all further life. However, little is known about the cellular processes behind this phenomenon. The study reported here used digital morphometry and immunolabelling for Pax7, myogenin and H3P to quantitatively examine the effects of thermal history on muscle precursor cell (MPC) behaviour and muscle growth in pearlfish (Rutilus meidingeri) until the adult stage. Fish were reared at three different temperatures (8.5, 13 and 16°C) until hatching and subsequently kept under the same (ambient) thermal conditions. Cellularity data were combined with a quantitative analysis of Pax7+ MPCs including those that were mitotically active (Pax7+/H3P+) or had entered differentiation (Pax7+/myogenin+). The results demonstrate that at hatching, body lengths, fast and slow muscle cross-sectional areas and fast fibre numbers are lower in fish reared at 8.5 and 13°C than at 16°C. During the larval period, this situation changes in the 13°C-fish, so that these fish are finally the largest. The observed effects can be related to divergent cellular mechanisms at the MPC level that are initiated in the embryo during the imprinting period. Embryos of 16°C-fish have reduced MPC proliferation but increased differentiation, and thus give rise to larger hatchlings. However, their limited MPC reserves finally lead to smaller adults. By contrast, embryos of 13°C-fish and, to a lesser extent, 8.5°-fish, show enhanced MPC proliferation but reduced differentiation, thus leading to smaller hatchlings but allowing for a larger MPC pool that can be used for enhanced post-hatching growth, finally resulting in larger adults.

  7. Deferoxamine immobilized poly(D,L-lactide) membrane via polydopamine adhesive coating: The influence on mouse embryo osteoblast precursor cells and human umbilical vein endothelial cells.

    Science.gov (United States)

    Li, Huihua; Luo, Binghong; Wen, Wei; Zhou, Changren; Tian, Lingling; Ramakrishna, Seeram

    2017-01-01

    Osteogenesis and angiogenesis play the prominent role in the bone regeneration. In this study, deferoxamine (DFO), an induced agent for osteogenesis and angiogenesis, was modified onto the surface of poly(D,L-lactide) (PDLLA) membrane via a facile and convenient approach based on the self-polymerization of dopamine (DOPA). The surface composition, morphology, hydrophilicity and surface energy of the original and modified PDLLA membranes were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electronic microscopy (SEM), atomic force microscopy (AFM) and contact angle measurement. The surface roughness and hydrophilicity of the PDLLA membrane were obviously increased by introducing either the single polydopamine (PDOPA) or the dual layers of PDOPA and DFO. In vitro cells culture experiments indicated that both the PDLLA/PDOPA and PDLLA/PDOPA-DFO composite membranes were more beneficial to the attachment, proliferation and spreading of MC3T3-E1 cells and HUVECs compared to the original PDLLA membrane. The PDLLA/PDOPA-DFO membrane was supportive for the proliferation of both MC3T3-E1