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Sample records for cell colony-forming cells

  1. Relationship of colony-stimulating activity to apparent kill of human colony-forming cells by irradiation and hydroxyurea

    International Nuclear Information System (INIS)

    Broxmeyer, H.E.; Galbraith, P.R.; Baker, F.L.

    1976-01-01

    Suspensions of human bone marrow cells were subjected to 137 Cs irradiation in vitro and then cultured in semisolid agar medium. Cultures of irradiated cells were stimulated with colony-stimulating activity (CSA) of different potencies, and it was found that the amount of stimulation applied to cultures influenced the apparent kill of colony-forming cells (CFC). It was also found that the effects of irradiation on colony formation were not confined to CFC kill since medium conditioned by cells during irradiation exhibited stimulatory and inhibitory properties after treatment by 600 and 1000 rads, respectively. Studies in which irradiated cells were pretreated with hydroxyurea indicated that CFC in the DNA synthetic phase of the cell cycle were particularly sensitive to low doses of irradiation. The proliferative capacity of CFC surviving 1000 rads was undiminished as judged by their ability to form large colonies. Estimates of CFC kill by hydroxyurea were also affected by the level of CSA

  2. Fabrication of corneal epithelial cell sheets maintaining colony-forming cells without feeder cells by oxygen-controlled method.

    Science.gov (United States)

    Nakajima, Ryota; Takeda, Shizu

    2014-01-01

    The use of murine 3T3 feeder cells needs to be avoided when fabricating corneal epithelial cell sheets for use in treating ocular surface diseases. However, the expression level of the epithelial stem/progenitor cell marker, p63, is down-regulated in feeder-free culture systems. In this study, in order to fabricate corneal epithelial cell sheets that maintain colony-forming cells without using any feeder cells, we investigated the use of an oxygen-controlled method that was developed previously to fabricate cell sheets efficiently. Rabbit limbal epithelial cells were cultured under hypoxia (1-10% O2) and under normoxia during stratification after reaching confluence. Multilayered corneal epithelial cell sheets were fabricated using an oxygen-controlled method, and immunofluorescence analysis showed that cytokeratin 3 and p63 was expressed in appropriate localization in the cell sheets. The colony-forming efficiency of the cell sheets fabricated by the oxygen-controlled method without feeder cells was significantly higher than that of cell sheets fabricated under 20% O2 without feeder cells. These results indicate that the oxygen-controlled method has the potential to achieve a feeder-free culture system for fabricating corneal epithelial cell sheets for corneal regeneration. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Increased numbers of spleen colony forming units in B cell deficient CBA/N mice

    International Nuclear Information System (INIS)

    Wiktor-Jedrzejczak, W.; Krupienicz, A.; Scher, I.

    1986-01-01

    The formation of exogenous and endogenous spleen colonies was studied in immune-defective mice expressing the CBA/N X-linked xid gene. Bone marrow and spleen cells of immune deficient mice formed increased numbers of eight-day exogenous spleen colonies when transferred to either normal or B cell deficient lethally irradiated recipients. Moreover, defective mice showed increased formation of five-day endogenous spleen colonies (derived from transient endogenous colony forming units; T-CFU) and of ten-day endogenous spleen colonies (derived from CFU-S). Among the possible mechanisms responsible for the observed effects, the most probable appears the one in which decreased numbers of B cell precursors stimulate stem cell pools through a feedback mechanism. (orig.) [de

  4. Responses of the Murine Myeloid Colony-Forming Cell to Ansamycin Antibiotics

    Science.gov (United States)

    Horoszewicz, Julius S.; Carter, William A.

    1974-01-01

    The in vitro susceptibility of murine myeloid colony-forming cells to the antiproliferative activities of three ansamycin antibiotics was determined. These cells were found to be 10- to 40-fold more susceptible than the corresponding human ones. PMID:4151701

  5. Identification and enrichment of colony-forming cells from the adult murine pituitary

    International Nuclear Information System (INIS)

    Lepore, D.A.; Roeszler, K.; Wagner, J.; Ross, S.A.; Bauer, K.; Thomas, P.Q.

    2005-01-01

    Stem and progenitor cells have been identified in many adult tissues including bone marrow, the central nervous system, and skin. While there is direct evidence to indicate the activity of a progenitor cell population in the pituitary gland, this putative subpopulation has not yet been identified. Herein we describe the isolation and characterization of a novel clonogenic cell type in the adult murine pituitary, which we have termed Pituitary Colony-Forming Cells (PCFCs). PCFCs constitute 0.2% of pituitary cells, and generate heterogeneous colonies from single cells. PCFCs exhibit variable proliferative potential, and may exceed 11 population doublings in 14 days. Enrichment of PCFCs to 61.5-fold with 100% recovery can be obtained through the active uptake of the fluorescent dipeptide, β-Ala-Lys-Nε-AMCA. PCFCs are mostly contained within the large, agranular subpopulation of AMCA + cells, and constitute 28% of this fraction, corresponding to 140.5-fold enrichment. Interestingly, the AMCA + population contains rare cells that are GH + or PRL + . GH + cells were also identified in PCFC single cell colonies, suggesting that PCFCs have the potential to differentiate into GH + cells. Together, these data show that the pituitary contains a rare clonogenic population which may correspond to the somatotrope/lactotrope progenitors suggested by previous experiments

  6. Binucleate cell formation correlates to loss of colony-forming ability in X-irradiated cultured mammalian cells

    International Nuclear Information System (INIS)

    Sasaki, H.; Yoshinaga, H.; Kura, S.

    1986-01-01

    The relationship between binucleate cell formation and the loss of colony-forming ability was examined in several cultured mammalian cell lines irradiated with X rays. The maximum fraction of binucleate cells after X irradiation increased dose-dependently within the range in which reproductive cell death might predominate over interphase cell death. When the logarithm of percentage survival was plotted against the percentage binucleate cells, a similar correlation was found for all cell lines tested, with the exception of mouse leukemia L5178Y cells, the most radiosensitive cells used. These observations suggest that the fraction of binucleate cells in the cell population can serve as a measure of cellular radiation damage

  7. Heterogeneity within the spleen colony-forming cell population in rat bone marrow

    International Nuclear Information System (INIS)

    Martens, A.C.; van Bekkum, D.W.; Hagenbeek, A.

    1986-01-01

    The pluripotent hemopoietic stem cell (HSC) of the rat can be enumerated in a spleen colony assay (SCA) in rats as well as mice. After injection of rat bone marrow into lethally irradiated mice, macroscopically visible spleen colonies (CFU-S) are found from day 6 through 14, but the number varies on consecutive days. In normal bone marrow a constant ratio of day-8 to day-12 colony numbers is observed. However, this ratio is changed after in vivo treatment of rats with cyclophosphamide, as well as after in vitro treatment of rat bone marrow with cyclophosphamide derivatives. This indicates that the CFU-S that form colonies on day 8 react differently to this treatment than the CFU-S that form colonies on day 12, and suggests heterogeneity among the CFU-S population. Posttreatment regrowth of day-8 and day-12 CFU-S is characterized by differences in population-doubling times (Td = 0.85 days vs 1.65 days). Another argument in support of the postulate of heterogeneity within the rat CFU-S population is derived from the fact that (in contrast to normal rat spleen) the spleen of leukemic rats contains high numbers of CFU-S that show a ratio of day-8 to day-12 CFU-S of 4.5, which is different than that observed for a CFU-S population in normal bone marrow (a ratio of 2.4). It is concluded that, in rat hemopoiesis, two populations of spleen colony-forming cells can be distinguished using the rat-to-mouse SCA. This indicates that mouse and rat hemopoiesis are comparable in this respect and that heterogeneity in the stem cell compartment is a general phenomenon

  8. Impaired T-lymphocyte colony formation by cord blood mononuclear cells

    International Nuclear Information System (INIS)

    Herrod, H.G.; Valenski, W.R.

    1982-01-01

    When compared to adult mononuclear cells, cord blood mononuclear cells demonstrated significantly decreased T-lymphocyte colony formation (1351 +/- 643 vs 592 +/- 862, P less than 0.01). This diminished colony-forming activity did not appear to be associated with impaired responsiveness to the stimulant phytohemagglutinin or with excessive suppressor-cell activity. Irradiation reduced the colony-forming capacity of cord blood mononuclear cells more than it did that of adult mononuclear cells. Depletion of adherent cells reduced cord blood mononuclear-cell colony-forming capacity by 40%, while similar treatment reduced adult colony formation by 10%. Lymphocyte proliferation in liquid culture of cord and adult cells was minimally affected by these procedures. The colony-forming capacity of cord blood could be enhanced by the addition of irradiated adult cells (284 +/- 72 vs 752 +/- 78, P less than 0.01). This enhancement was demonstrated to be due to a soluble factor produced by a population of irradiated adult cells depleted of the OKT8+ subpopulation of lymphocytes. These results indicate that the progenitor cells of T-lymphocyte colonies in cord blood have distinct biologic characteristics when compared to colony progenitors present in adult blood. This assay may prove to be useful in our efforts to understand the differentiation of T-cell function in man

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

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    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).

  10. Functional Differences Between Placental Micro- and Macrovascular Endothelial Colony-Forming Cells

    Science.gov (United States)

    Solomon, Ioana; O’Reilly, Megan; Ionescu, Lavinia; Alphonse, Rajesh S.; Rajabali, Saima; Zhong, Shumei; Vadivel, Arul; Shelley, W. Chris; Yoder, Mervin C.

    2016-01-01

    Alterations in the development of the placental vasculature can lead to pregnancy complications, such as preeclampsia. Currently, the cause of preeclampsia is unknown, and there are no specific prevention or treatment strategies. Further insight into the placental vasculature may aid in identifying causal factors. Endothelial colony-forming cells (ECFCs) are a subset of endothelial progenitor cells capable of self-renewal and de novo vessel formation in vitro. We hypothesized that ECFCs exist in the micro- and macrovasculature of the normal, term human placenta. Human placentas were collected from term pregnancies delivered by cesarean section (n = 16). Placental micro- and macrovasculature was collected from the maternal and fetal side of the placenta, respectively, and ECFCs were isolated and characterized. ECFCs were CD31+, CD105+, CD144+, CD146+, CD14−, and CD45−, took up 1,1′-dioctadecyl-3,3,3′,3′-tetramethyl-indocarbocyanine perchlorate-labeled acetylated low-density lipoprotein, and bound Ulex europaeus agglutinin 1. In vitro, macrovascular ECFCs had a greater potential to generate high-proliferative colonies and formed more complex capillary-like networks on Matrigel compared with microvascular ECFCs. In contrast, in vivo assessment demonstrated that microvascular ECFCs had a greater potential to form vessels. Macrovascular ECFCs were of fetal origin, whereas microvascular ECFCs were of maternal origin. ECFCs exist in the micro- and macrovasculature of the normal, term human placenta. Although macrovascular ECFCs demonstrated greater vessel and colony-forming potency in vitro, this did not translate in vivo, where microvascular ECFCs exhibited a greater vessel-forming ability. These important findings contribute to the current understanding of normal placental vascular development and may aid in identifying factors involved in preeclampsia and other pregnancy complications. Significance This research confirms that resident endothelial colony-forming

  11. Isolation and characterization of human umbilical cord-derived endothelial colony-forming cells

    Science.gov (United States)

    Zhang, Hao; Tao, Yanling; Ren, Saisai; Liu, Haihui; Zhou, Hui; Hu, Jiangwei; Tang, Yongyong; Zhang, Bin; Chen, Hu

    2017-01-01

    Endothelial colony-forming cells (ECFCs) are a population of endothelial progenitor cells (EPCs) that display robust proliferative potential and vessel-forming capability. Previous studies have demonstrated that a limited number of ECFCs may be obtained from adult bone marrow, peripheral blood and umbilical cord (UC) blood. The present study describes an effective method for isolating ECFCs from human UC. The ECFCs derived from human UC displayed the full properties of EPCs. Analysis of the growth kinetics, cell cycle and colony-forming ability of the isolated human UC-ECFCs indicated that the cells demonstrated properties of stem cells, including relative stability and rapid proliferation in vitro. Gene expression of Fms related tyrosine kinase 1, kinase insert domain receptor, vascular endothelial cadherin, cluster of differentiation (CD)31, CD34, epidermal growth factor homology domains-2, von Willebrand factor and endothelial nitric oxide synthase was assessed by reverse transcription-polymerase chain reaction. The cells were positive for CD34, CD31, CD73, CD105 and vascular endothelial growth factor receptor-2, and negative for CD45, CD90 and human leukocyte antigen-antigen D related protein according to flow cytometry. 1,1′-dioctadecyl-3,3,3′,3′-tetra-methyl-indocarbocyanine perchlorate-labeled acetylated low-density lipoprotein and fluorescein isothiocyanate-Ulex europaeus-l were used to verify the identity of the UC-ECFCs. Matrigel was used to investigate tube formation capability. The results demonstrated that the reported technique is a valuable method for isolating human UC-ECFCs, which have potential for use in vascular regeneration. PMID:29067104

  12. Single cell time-lapse analysis reveals that podoplanin enhances cell survival and colony formation capacity of squamous cell carcinoma cells.

    Science.gov (United States)

    Miyashita, Tomoyuki; Higuchi, Youichi; Kojima, Motohiro; Ochiai, Atsushi; Ishii, Genichiro

    2017-01-06

    Tumor initiating cells (TICs) are characterized by high clonal expansion capacity. We previously reported that podoplanin is a TIC-specific marker for the human squamous cell carcinoma cell line A431. The aim of this study is to explore the molecular mechanism underlying the high clonal expansion potential of podoplanin-positive A431cells using Fucci imaging. Single podoplanin-positive cells created large colonies at a significantly higher frequency than single podoplanin-negative cells, whereas no difference was observed between the two types of cells with respect to cell cycle status. Conversely, the cell death ratio of progenies derived from podoplanin-positive single cell was significantly lower than that of cells derived from podoplanin-negative cells. Single A431 cells, whose podoplanin expression was suppressed by RNA interference, exhibited increased cell death ratios and decreased frequency of large colony forming. Moreover, the frequency of large colony forming decreased significantly when podoplanin-positive single cells was treated with a ROCK (Rho-associated coiled-coil kinase) inhibitor, whereas no difference was observed in single podoplanin-negative cells. Our current study cleared that high clonal expansion capacity of podoplanin-positive TICs populations was the result of reduced cell death by podoplanin-mediated signaling. Therefore, podoplanin activity may be a therapeutic target in the treatment of squamous cell carcinomas.

  13. Increase in colony-forming efficiency in soft agar of thymus cells from radiation-induced thymomas of NIH Swiss mice

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    Mori, Nobuko; Takamori, Yasuhiko; Hori, Yasuharu [Radiation Center of Osaka Prefecture, Sakai (Japan)

    1982-03-01

    Colony-forming efficiency in soft agar of radiation-induced thymoma in NIH Swiss mice was determined in the presence of cultured medium of reticulo-epitherial cells from normal thymus of NIH Swiss mouse as conditioned medium. A similar experiment was done with thymomas spontaneously developed in AKR mice. Most of colonies developed in soft agar were not composed of thymic lymphoma cells, but of macrophage-like cells. The ratio of the number of colonies to that of the seeded cells significantly increased in thymomas comparing with that in normal thymus. This result corresponded with the increased number of macrophages in thymoma, as determined by counting phagocytic cells of adherent cells.

  14. Effect of adrenalectomy on recipients of allogeneic lymphocytes on inactivation of endogenous colony-forming cells in mice

    International Nuclear Information System (INIS)

    Semenkov, V.F.

    1985-01-01

    This paper presents a study of the killer functions of lymph node cells directed against endogenous colony-forming cells in adrenalectomized recipients in a genetic system with one-way incompatibility: parental line - F 1 hybrid. Mice were irradiated with Co 60 gamma rays on the EGO-2 apparatus with dose rate from 200 to 250 R/min. The results were subjected to statistical analysis by Student's test. It can be tentatively suggested that the killer action of T lymphocytes on endogenous colonies was intensified in adrenal-ectomized recipients with endogenous hypocorticism, as a result of cooperation with the cortisol-sensitive subpopulation of T helper cells, of a change in the properties of the antigen-recognizing receptors, or an increase in the sensitivity of target cells to the killer action of T lymphocytes

  15. Precursors (pre-CFCmulti) of multilineage hemopoietic colony-forming cells quantitated in vitro. Uniqueness of IL-1 requirement, partial separation from pluripotential colony-forming cells, and correlation with long term reconstituting cells in vivo

    International Nuclear Information System (INIS)

    Iscove, N.N.; Yan, X.Q.

    1990-01-01

    Pluripotential colony-forming cells (CFCmulti) from mouse marrow can expand significantly in number during 4 days of suspension culture with IL-1 and IL-3. In this study, the cells (pre-CFCmulti) which originate this response are characterized in terms of their frequency, progeny number, factor requirements, buoyant density, and extent of restoration following marrow transplantation. Parallel measurements of both CFCmulti and cells providing long term marrow reconstitution in vivo allowed direct comparisons to be made with pre-CFCmulti. The proliferative response of pre-CFCmulti was found to depend uniquely on the combination of IL-1 and IL-3, and neither of these regulators was replaceable by any of IL-4, IL-6, IL-7, GM-CSF, G-CSF, M-CSF or LIF. After separation on density gradients, pre-CFCmulti were recovered in fractions of lower density than most of the CFCmulti, but in the same fractions that contained most of the in vivo reconstituting cells. After irradiation and marrow transplantation, marrow CFCmulti were restored to near normal levels, while both pre-CFCmulti as well as reconstituting stem cells remained profoundly depressed. These results show pre-CFCmulti to be distinct from most CFCmulti and to represent the closest approach to quantitative detection of reconstituting stem cells so far achieved in vitro

  16. Isolation of endothelial colony-forming cells from blood samples collected from the jugular and cephalic veins of healthy adult horses.

    Science.gov (United States)

    Sharpe, Ashley N; Seeto, Wen J; Winter, Randolph L; Zhong, Qiao; Lipke, Elizabeth A; Wooldridge, Anne A

    2016-10-01

    OBJECTIVE To evaluate optimal isolation of endothelial colony-forming cells (ECFCs) from peripheral blood of horses. SAMPLE Jugular and cephalic venous blood samples from 17 adult horses. PROCEDURES Each blood sample was divided; isolation was performed with whole blood adherence (WBA) and density gradient centrifugation (DGC). Isolated cells were characterized by uptake of 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate-labeled acetylated low-density lipoprotein (DiI-Ac-LDL), vascular tubule formation, and expression of endothelial (CD34, CD105, vascular endothelial growth factor receptor-2, and von Willebrand factor) and hematopoietic (CD14) cell markers by use of indirect immunofluorescence assay (IFA) and flow cytometry. RESULTS Colonies with cobblestone morphology were isolated from 15 of 17 horses. Blood collected from the cephalic vein yielded colonies significantly more often (14/17 horses) than did blood collected from the jugular vein (8/17 horses). Of 14 cephalic blood samples with colonies, 13 were obtained with DGC and 8 with WBA. Of 8 jugular blood samples with colonies, 8 were obtained with DGC and 4 with WBA. Colony frequency (colonies per milliliter of blood) was significantly higher for cephalic blood samples and samples isolated with DGC. Cells formed vascular tubules, had uptake of DiI-Ac-LDL, and expressed endothelial markers by use of IFA and flow cytometry, which confirmed their identity as ECFCs. CONCLUSIONS AND CLINICAL RELEVANCE Maximum yield of ECFCs was obtained for blood samples collected from both the jugular and cephalic veins and use of DGC to isolate cells. Consistent yield of ECFCs from peripheral blood of horses will enable studies to evaluate diagnostic and therapeutic uses.

  17. The Transcription Factor Nrf2 Protects Angiogenic Capacity of Endothelial Colony-Forming Cells in High-Oxygen Radical Stress Conditions

    NARCIS (Netherlands)

    Gremmels, Hendrik; De Jong, Olivier G.; Hazenbrink, Diënty H.; Fledderus, Joost O.; Verhaar, Marianne C.

    2017-01-01

    Background. Endothelial colony forming cells (ECFCs) have shown a promise in tissue engineering of vascular constructs, where they act as endothelial progenitor cells. After implantation, ECFCs are likely to be subjected to elevated reactive oxygen species (ROS). The transcription factor Nrf2

  18. Endogenous Sheet-Averaged Tension Within a Large Epithelial Cell Colony.

    Science.gov (United States)

    Dumbali, Sandeep P; Mei, Lanju; Qian, Shizhi; Maruthamuthu, Venkat

    2017-10-01

    Epithelial cells form quasi-two-dimensional sheets that function as contractile media to effect tissue shape changes during development and homeostasis. Endogenously generated intrasheet tension is a driver of such changes, but has predominantly been measured in the presence of directional migration. The nature of epithelial cell-generated forces transmitted over supracellular distances, in the absence of directional migration, is thus largely unclear. In this report, we consider large epithelial cell colonies which are archetypical multicell collectives with extensive cell-cell contacts but with a symmetric (circular) boundary. Using the traction force imbalance method (TFIM) (traction force microscopy combined with physical force balance), we first show that one can determine the colony-level endogenous sheet forces exerted at the midline by one half of the colony on the other half with no prior assumptions on the uniformity of the mechanical properties of the cell sheet. Importantly, we find that this colony-level sheet force exhibits large variations with orientation-the difference between the maximum and minimum sheet force is comparable to the average sheet force itself. Furthermore, the sheet force at the colony midline is largely tensile but the shear component exhibits significantly more variation with orientation. We thus show that even an unperturbed epithelial colony with a symmetric boundary shows significant directional variation in the endogenous sheet tension and shear forces that subsist at the colony level.

  19. Effect of barbiturates on radiosensitivity of cells: a comparative study of electrophoretic mobility, colony forming ability and thymidine uptake on human amnion cells

    International Nuclear Information System (INIS)

    Lalwani, N.D.; Chaubal, K.A.

    1980-01-01

    Suspensions of human amnion cells were 60 Co γ-irradiated in the presence of phenobarbital or thiobarbital (50 μg/ml). The barbiturates protected the cells against the dose-dependent reduction in electrophoretic mobility (EPM) observed 4 hours after irradiation of untreated cells, although there was an initial decrease in the EPM of treated cells followed by recovery. Treated irradiated cells exhibited greater colony-forming ability than the untreated cells. Pentobarbital and phenobarbital had similar effects, but thiobarbital was not so effective. 3 H-TdR uptake increased within 4 hours of irradiation for the treated cells. The reproductive capacity of the cells was retained at doses as high as 500 rad. The results are discussed with reference to the effects of anaesthetics on cell membranes. (U.K.)

  20. Study of budding yeast colony formation and its characterizations by using circular granular cell

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    Aprianti, D.; Haryanto, F.; Purqon, A.; Khotimah, S. N.; Viridi, S.

    2016-03-01

    Budding yeast can exhibit colony formation in solid substrate. The colony of pathogenic budding yeast can colonize various surfaces of the human body and medical devices. Furthermore, it can form biofilm that resists drug effective therapy. The formation of the colony is affected by the interaction between cells and with its growth media. The cell budding pattern holds an important role in colony expansion. To study this colony growth, the molecular dynamic method was chosen to simulate the interaction between budding yeast cells. Every cell was modelled by circular granular cells, which can grow and produce buds. Cohesion force, contact force, and Stokes force govern this model to mimic the interaction between cells and with the growth substrate. Characterization was determined by the maximum (L max) and minimum (L min) distances between two cells within the colony and whether two lines that connect the two cells in the maximum and minimum distances intersect each other. Therefore, it can be recognized the colony shape in circular, oval, and irregular shapes. Simulation resulted that colony formation are mostly in oval shape with little branch. It also shows that greater cohesion strength obtains more compact colony formation.

  1. Human T cell colony formation in microculture: analysis of growth requirements and functional activities.

    Science.gov (United States)

    Gelfand, E W; Lee, J W; Dosch, H M; Price, G B

    1981-03-01

    A microculture method in methylcellulose has been developed for the study of human T cell colony formation. The technique is simple, reliable, does not require preincubation with lectin and requires small numbers of cells. Colony formation was dependent on the presence of phytohemagglutin-conditioned medium, a T colony precursor cell (TCPC), and a "helper" or accessory T cell. Plating efficiency was increased 10-fold in the presence of irradiated feeder cells. Progenitors of the T colony cells were identified in peripheral blood, tonsil, and spleen but not in thymus or thoracic duct. They were isolated in the E-rosetting, theophylline-resistant, Fc-IgG-negative cell populations. In peripheral blood the frequency of TCPC and accessory cells, the T colony forming unit, was estimated to be 8 X 10(-3). Colony cells proliferated in response to lectins and allogeneic cells. Forty to 80% of the cells were Ia-positive and stimulated both autologous and allogeneic mixed lymphocyte responses. They were incapable of mediating antibody-dependent cytotoxicity. In contrast, they were effective in assays of spontaneous cytotoxicity but only against certain target cells. This method for the analysis of T colony formation should prove valuable in the functional analysis of T cell subsets in immunodeficiency states or the transplant recipient.

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

    Science.gov (United States)

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

    2014-11-15

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

  3. Photoreactivation of ultraviolet light-induced damage in cultured fish cells as revealed by increased colony forming ability and decreased content of pyrimidine dimers

    International Nuclear Information System (INIS)

    Shima, A.; Ikenaga, M.; Egami, N.

    1981-01-01

    Cultured cells derived from a goldfish were irradiated with 254 nm ultraviolet light. Cell survival and splitting of pyrimidine dimers after photoreactivation treatment with white fluorescent lamps were examined by colony forming ability and by a direct dimer assay, respectively. When UV-irradiated (5 J/m 2 ) cells were illuminated by photoreactivating light, cell survival was enhanced up to a factor of 9(40 min) followed by a decline after prolonged exposures. Exposure of UV-irradiated (15 J/m 2 ) cells to radiation from white fluorescent lamps reduced the amounts of thymine-containing dimers in a photoreactivating fluence dependent manner, up to about 60% reduction at 120 min exposure. Keeping UV-irradiated cells in the dark for up to 120 min did not affect either cell survival or the amount of pyrimidine dimers in DNA, indicating that there were not detectable levels of a dark-repair system in the cells under our conditions. Correlation between photoreactivation of colony forming ability and photoreactivation of the pyrimidine dimers was demonstrated, at least at relatively low fluences of photoreactivating light. (author)

  4. Photoreactivation of ultraviolet light-induced damage in cultured fish cells as revealed by increased colony forming ability and decreased content of pyrimidine dimers

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    Shima, A. (Shiga University of Medical Science, Otsu (Japan)); Ikenaga, M. (Osaka Univ. (Japan). Faculty of Medicine); Nikaido, O.; Takebe, H. (Kyoto Univ. (Japan)); Egami, N. (Tokyo Univ. (Japan). Faculty of Science)

    1981-03-01

    Cultured cells derived from a goldfish were irradiated with 254 nm ultraviolet light. Cell survival and splitting of pyrimidine dimers after photoreactivation treatment with white fluorescent lamps were examined by colony forming ability and by a direct dimer assay, respectively. When UV-irradiated (5 J/m/sup 2/) cells were illuminated by photoreactivating light, cell survival was enhanced up to a factor of 9(40 min) followed by a decline after prolonged exposures. Exposure of UV-irradiated (15 J/m/sup 2/) cells to radiation from white fluorescent lamps reduced the amounts of thymine-containing dimers in a photoreactivating fluence dependent manner, up to about 60% reduction at 120 min exposure. Keeping UV-irradiated cells in the dark for up to 120 min did not affect either cell survival or the amount of pyrimidine dimers in DNA, indicating that there were not detectable levels of a dark-repair system in the cells under our conditions. Correlation between photoreactivation of colony forming ability and photoreactivation of the pyrimidine dimers was demonstrated, at least at relatively low fluences of photoreactivating light.

  5. Optimization of the culturing conditions of human umbilical cord blood-derived endothelial colony-forming cells under xeno-free conditions applying a transcriptomic approach

    NARCIS (Netherlands)

    Zeisberger, Steffen M.; Zoller, Stefan; Riegel, Mariluce; Chen, Shuhua; Krenning, Guido; Harmsen, Martin C.; Sachinidis, Agapios; Zisch, Andreas H.

    Establishment of fetal bovine serum (FBS)-free cell culture conditions is essential for transplantation therapies. Blood-derived endothelial colony-forming cells (ECFCs) are potential candidates for regenerative medicine applications. ECFCs were isolated from term umbilical cord blood units and

  6. A stimulator of proliferation of spleen colony-forming cells (CFU-S) in the bone marrow of irradiated rats

    Energy Technology Data Exchange (ETDEWEB)

    Ivanovic, Z.; Milenkovic, P.; Stojanovic, N.; Lukic, M.; Kataranovski, M.

    1993-07-01

    The presence and activity of a spleen colony - forming cell (CFU-S) proliferation stimulator was investigated in rat bone marrow after irradiation. The dose dependent increase in cytosine arabinoside induced cell dealth of normal mouse bone marrow. The results demonstrate the existence of a CFU-S proliferation stimulator in rat bone marrow similar to that originally found as a macrophage product in regenarating mouse bone marrow. The CFU-S proliferation stimulator activity was not associated with the presence of interleukin - 1,2, or 6 like activities in the material tested.

  7. Matrix production and organization by endothelial colony forming cells in mechanically strained engineered tissue constructs.

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    Nicky de Jonge

    Full Text Available AIMS: Tissue engineering is an innovative method to restore cardiovascular tissue function by implanting either an in vitro cultured tissue or a degradable, mechanically functional scaffold that gradually transforms into a living neo-tissue by recruiting tissue forming cells at the site of implantation. Circulating endothelial colony forming cells (ECFCs are capable of differentiating into endothelial cells as well as a mesenchymal ECM-producing phenotype, undergoing Endothelial-to-Mesenchymal-transition (EndoMT. We investigated the potential of ECFCs to produce and organize ECM under the influence of static and cyclic mechanical strain, as well as stimulation with transforming growth factor β1 (TGFβ1. METHODS AND RESULTS: A fibrin-based 3D tissue model was used to simulate neo-tissue formation. Extracellular matrix organization was monitored using confocal laser-scanning microscopy. ECFCs produced collagen and also elastin, but did not form an organized matrix, except when cultured with TGFβ1 under static strain. Here, collagen was aligned more parallel to the strain direction, similar to Human Vena Saphena Cell-seeded controls. Priming ECFC with TGFβ1 before exposing them to strain led to more homogenous matrix production. CONCLUSIONS: Biochemical and mechanical cues can induce extracellular matrix formation by ECFCs in tissue models that mimic early tissue formation. Our findings suggest that priming with bioactives may be required to optimize neo-tissue development with ECFCs and has important consequences for the timing of stimuli applied to scaffold designs for both in vitro and in situ cardiovascular tissue engineering. The results obtained with ECFCs differ from those obtained with other cell sources, such as vena saphena-derived myofibroblasts, underlining the need for experimental models like ours to test novel cell sources for cardiovascular tissue engineering.

  8. Human endothelial colony-forming cells expanded with an improved protocol are a useful endothelial cell source for scaffold-based tissue engineering.

    Science.gov (United States)

    Denecke, Bernd; Horsch, Liska D; Radtke, Stefan; Fischer, Johannes C; Horn, Peter A; Giebel, Bernd

    2015-11-01

    One of the major challenges in tissue engineering is to supply larger three-dimensional (3D) bioengineered tissue transplants with sufficient amounts of nutrients and oxygen and to allow metabolite removal. Consequently, artificial vascularization strategies of such transplants are desired. One strategy focuses on endothelial cells capable of initiating new vessel formation, which are settled on scaffolds commonly used in tissue engineering. A bottleneck in this strategy is to obtain sufficient amounts of endothelial cells, as they can be harvested only in small quantities directly from human tissues. Thus, protocols are required to expand appropriate cells in sufficient amounts without interfering with their capability to settle on scaffold materials and to initiate vessel formation. Here, we analysed whether umbilical cord blood (CB)-derived endothelial colony-forming cells (ECFCs) fulfil these requirements. In a first set of experiments, we showed that marginally expanded ECFCs settle and survive on different scaffold biomaterials. Next, we improved ECFC culture conditions and developed a protocol for ECFC expansion compatible with 'Good Manufacturing Practice' (GMP) standards. We replaced animal sera with human platelet lysates and used a novel type of tissue-culture ware. ECFCs cultured under the new conditions revealed significantly lower apoptosis and increased proliferation rates. Simultaneously, their viability was increased. Since extensively expanded ECFCs could still settle on scaffold biomaterials and were able to form tubular structures in Matrigel assays, we conclude that these ex vivo-expanded ECFCs are a novel, very potent cell source for scaffold-based tissue engineering. Copyright © 2013 John Wiley & Sons, Ltd.

  9. An improved method for staining cell colonies in clonogenic assays.

    Science.gov (United States)

    Guda, Kishore; Natale, Leanna; Markowitz, Sanford D

    2007-06-01

    Clonogenic assay is a widely used experimental approach to test for the effects of drugs/genes on the growth and proliferative characteristics of cells in vitro. Accurate quantitation of treatment effects in clonogeneic assays depends on the ability to visualize and count cell colonies precisely. We report a novel method (referred as ETeB) for staining cell colonies grown on plastic and specially coated substrates like collagen. Using colon cancer cell lines grown on plastic and collagen, we compared the colony staining efficiencies of the widely used methylene blue, and Ethidium bromide (ETeB) stains. Results show that the ETeB protocol works well on plastic and is extremely effective for staining colonies on collagen when compared to methylene blue. The key features and advantages of ETeB technique are; (a) reduction in background for colonies grown on collagen and possibly other substrates, (b) the whole procedure takes less than a minute, (c) no post-stain washing step is required which eliminates colony losses for cell lines that are loosely adherent, (d) colony visualization and counting can be done immediately following the staining procedure using a standard UV illuminator and software, and (e) the method works across a wide variety of cell lines. The simplicity and robustness of this procedure should warrant its usage in both small and large-scale clonogenic experiments.

  10. Colony variation of Helicobacter pylori: pathogenic potential is correlated to cell wall lipid composition.

    Science.gov (United States)

    Bukholm, G; Tannaes, T; Nedenskov, P; Esbensen, Y; Grav, H J; Hovig, T; Ariansen, S; Guldvog, I

    1997-05-01

    Differences in expression of disease after infection with Helicobacter pylori have so far been connected with host factors and bacterial interstrain variation. In this study, spontaneous and ecology-mediated intrastrain variation was examined. Four clinical isolates of H. pylori were shown to give rise to two colony forms. Bacterial morphology was examined by electron microscopy. Bacterial fractions were examined for proteins using ion exchange chromatography and SDS-PAGE; for lipids using thin-layer chromatography, lipid anion-exchange chromatography, column chromatography on silica gel, 31P-NMR, gas chromatography and mass spectrometry. Bacterial in vitro invasiveness and adhesiveness were examined in two different systems, and urease and VacA toxin were assayed by Western blot analysis. H. pylori was shown to give rise to two colony forms: at normal pH the population was dominated by L colonies. One strain was chosen for further studies. Bacteria from L colonies retained VacA toxin and urease, did not invade or adhere to epithelial cells, and contained normal quantities of phosphatidylethanolamine. In a small frequency, spontaneous S colonies were formed. Bacteria from these colonies released VacA and urease, adhered to and invaded epithelial cells and contained increased amounts of lysophosphatidyl ethanolamine and phosphatidyl serine. After addition of HCl to the culture medium (pH6), almost only S colonies were formed. The results demonstrate that environmental factors, such as HCl, can change the bacterial cell wall, and thereby enhance expression of virulence factors of H. pylori in vitro. A similar in vivo variation would have implications for our understanding of the interaction between HCl secretion in the gastric mucosa and H. pylori in the development of peptic ulcer disease.

  11. Exercise increases the frequency of circulating hematopoietic progenitor cells, but reduces hematopoietic colony-forming capacity.

    Science.gov (United States)

    Kroepfl, Julia Maria; Pekovits, Karin; Stelzer, Ingeborg; Fuchs, Robert; Zelzer, Sieglinde; Hofmann, Peter; Sedlmayr, Peter; Dohr, Gottfried; Wallner-Liebmann, Sandra; Domej, Wolfgang; Mueller, Wolfram

    2012-11-01

    Circulating hematopoietic progenitor cells (CPCs) may be triggered by physical exercise and/or normobaric hypoxia from the bone marrow. The aim of the study was to investigate the influence of physical exercise and normobaric hypoxia on CPC number and functionality in the peripheral blood as well as the involvement of oxidative stress parameters as possibly active agents. Ten healthy male subjects (25.3±4.4 years) underwent a standardized cycle incremental exercise test protocol (40 W+20 W/min) under either normoxic (FiO2 ∼0.21) or hypoxic conditions (FiO2exercise. The number of CPCs in the peripheral blood was analyzed by flow cytometry (CD34/CD45-positive cells). The functionality of cells present was addressed by secondary colony-forming unit-granulocyte macrophage (CFU-GM) assays. To determine a possible correlation between the mobilization of CPCs and reactive oxygen species, parameters for oxidative stress such as malondialdehyde (MDA) and myeloperoxidase (MPO) were obtained. Data showed a significant increase of CPC release under normoxic as well as hypoxic conditions after 10 min of recovery (Pexercise (Pexercise, possibly due to the influence of increased oxidative stress levels.

  12. Effect of X-Rays on Growth Rate of Rose Shoot Cultures and the Ability of Isolated Protoplasts to Form Cell Colonies

    International Nuclear Information System (INIS)

    Moustafa, R. A. K.

    2004-01-01

    The popularity of rose as a garden plant, allied with its use in the production of cut flowers and also as a source of aromatic rose oils, make it one of the most important ornamental crops. Roses, however, have suffered from a narrow genetic base to which only few species have contributed significantly. In vitro culture of plants might facilitate the improvement of rose via the exploitation of somaclonal variation to generate new genetic variability and selection within the variation for desirable traits. The application of mutagens for in vitro cultures, in addition to the induced mutations, may lead to increase the somaclonal variation, thus providing additional variation for selection. On the other hand, plant protoplasts offer exciting possibilities to establish in vitro selection programs based on single cells. Induced variation in isolated protoplasts using mutagen agents may be one mean to select useful mutants. Thus the present experiments were conducted to determine the effect of X-rays on shoot cultures and the isolated protoplasts of rose (Rosa sp.). The materials consisted of the three rose varieties Rosa wichuriana, Paricer charm and Heckenzauber.The applied doses were 0, 10, 20, 30, 40, 50 and 60 Gy. Obtained results indicated that the genotypes differed in their sensitivity to X-rays. Rosa wichuriana seemed to be the most sensitive variety to radiation, where a dose of 20 Gy caused approximately 50% reduction in growth rate of shoot cultures, while the same dose decreased the growth rate of Paricer charm only by 25% and did not affect the growth of Heckenzauber. Results also revealed that the ability of irradiated protoplasts to form cell colonies increased when a dose of 10 Gy was performed. Doses higher than that level caused gradual decreasing in the forming of cell colonies, but however, the protoplasts could form colonies even when a dose of 60 Gy was applied. (Author)

  13. An improved method for staining cell colonies in clonogenic assays

    OpenAIRE

    Guda, Kishore; Natale, Leanna; Markowitz, Sanford D.

    2007-01-01

    Clonogenic assay is a widely used experimental approach to test for the effects of drugs/genes on the growth and proliferative characteristics of cells in vitro. Accurate quantitation of treatment effects in clonogeneic assays depends on the ability to visualize and count cell colonies precisely. We report a novel method (referred as ETeB) for staining cell colonies grown on plastic and specially coated substrates like collagen. Using colon cancer cell lines grown on plastic and collagen, we ...

  14. Longevity of U cells of differentiated yeast colonies grown on respiratory medium depends on active glycolysis.

    Science.gov (United States)

    Čáp, Michal; Váchová, Libuše; Palková, Zdena

    2015-01-01

    Colonies of Saccharomyces cerevisiae laboratory strains pass through specific developmental phases when growing on solid respiratory medium. During entry into the so-called alkali phase, in which ammonia signaling is initiated, 2 prominent cell types are formed within the colonies: U cells in upper colony regions, which have a longevity phenotype and activate the expression of a large number of metabolic genes, and L cells in lower regions, which die more quickly and exhibit a starvation phenotype. Here, we performed a detailed analysis of the activities of enzymes of central carbon metabolism in lysates of both cell types and determined several fermentation end products, showing that previously reported expression differences are reflected in the different enzymatic capabilities of each cell type. Hence, U cells, despite being grown on respiratory medium, behave as fermenting cells, whereas L cells rely on respiratory metabolism and possess active gluconeogenesis. Using a spectrum of different inhibitors, we showed that glycolysis is essential for the formation, and particularly, the survival of U cells. We also showed that β-1,3-glucans that are released from the cell walls of L cells are the most likely source of carbohydrates for U cells.

  15. Stem cells in Nanomia bijuga (Siphonophora), a colonial animal with localized growth zones.

    Science.gov (United States)

    Siebert, Stefan; Goetz, Freya E; Church, Samuel H; Bhattacharyya, Pathikrit; Zapata, Felipe; Haddock, Steven H D; Dunn, Casey W

    2015-01-01

    Siphonophores (Hydrozoa) have unparalleled colony-level complexity, precision of colony organization, and functional specialization between zooids (i.e., the units that make up colonies). Previous work has shown that, unlike other colonial animals, most growth in siphonophores is restricted to one or two well-defined growth zones that are the sites of both elongation and zooid budding. It remained unknown, however, how this unique colony growth and development is realized at the cellular level. To understand the colony-level growth and development of siphonophores at the cellular level, we characterize the distribution of proliferating cells and interstitial stem cells (i-cells) in the siphonophore Nanomia bijuga. Within the colony, we find evidence that i-cells are present at the tip of the horn, the structure within the growth zone that gives rise to new zooids. Co-localized gene expression of vasa-1, pl10, piwi, nanos-1, and nanos-2 suggests that i-cells persist in the youngest zooid buds and that i-cells become progressively restricted to specific regions within the zooids until they are mostly absent from the oldest zooids. The examined genes remain expressed in gametogenic regions. No evidence for i-cells is found in the stem between maturing zooids. Domains of high cell proliferation include regions where the examined genes are expressed, but also include some areas in which the examined genes were not expressed such as the stem within the growth zones. Cell proliferation in regions devoid of vasa-1, pl10, piwi, nanos-1, and nanos-2 expression indicates the presence of mitotically active epithelial cell lineages and, potentially, progenitor cell populations. We provide the first evidence for i-cells in a siphonophore. Our findings suggest maintenance of i-cell populations at the sites of growth zones and that these sites are the main source of i-cells. This restriction of stem cells to particular regions in the colony, in combination with localized budding

  16. Colony, hanging drop, and methylcellulose three dimensional hypoxic growth optimization of renal cell carcinoma cell lines.

    Science.gov (United States)

    Matak, Damian; Brodaczewska, Klaudia K; Lipiec, Monika; Szymanski, Łukasz; Szczylik, Cezary; Czarnecka, Anna M

    2017-08-01

    Renal cell carcinoma (RCC) is the most lethal of the common urologic malignancies, comprising 3% of all human neoplasms, and the incidence of kidney cancer is rising annually. We need new approaches to target tumor cells that are resistant to current therapies and that give rise to recurrence and treatment failure. In this study, we focused on low oxygen tension and three-dimensional (3D) cell culture incorporation to develop a new RCC growth model. We used the hanging drop and colony formation methods, which are common in 3D culture, as well as a unique methylcellulose (MC) method. For the experiments, we used human primary RCC cell lines, metastatic RCC cell lines, human kidney cancer stem cells, and human healthy epithelial cells. In the hanging drop assay, we verified the potential of various cell lines to create solid aggregates in hypoxic and normoxic conditions. With the semi-soft agar method, we also determined the ability of various cell lines to create colonies under different oxygen conditions. Different cell behavior observed in the MC method versus the hanging drop and colony formation assays suggests that these three assays may be useful to test various cell properties. However, MC seems to be a particularly valuable alternative for 3D cell culture, as its higher efficiency of aggregate formation and serum independency are of interest in different areas of cancer biology.

  17. Method of monolayer cultures of the guinea pig spleen used to evaluate the radioprotective action of mexamine on the survival of colony-forming cells. [Method of monolayer cultures, quantitative estimation of radioprotective action of drugs

    Energy Technology Data Exchange (ETDEWEB)

    Baisogolov, G D; Rudakova, S F; Rudakov, I A; Konoplyannikov, A G [Akademiya Meditsinskikh Nauk SSSR, Obninsk. Nauchno-Issledovatel' skij Inst. Meditsinskoj Radiologii

    1976-01-01

    Dose dependent survival of colony-forming splenic cells of guinea pigs has been studied after ..gamma..-irradiation in vitro. The average lethal dose (D/sub 0/) for colony-forming cells is 245 rads, the extrapolation number - 1.5. Radiosensitivity of the splenic cells is markedly lower than that of the bone marrow cells (128 rads). After intraperitoneal administration of mexamine (150 mg/kg) to guinea pigs 10-15 min before irradiation, D/sub 0/ increases up to 319 rads, extrapolation number is 1.4, and DRF is 1.3.

  18. Changes in numbers and types of mast cell colony-forming cells in the peritoneal cavity of mice after injection of distilled water: evidence that mast cells suppress differentiation of bone marrow-derived precursors

    International Nuclear Information System (INIS)

    Kanakura, Y.; Kuriu, A.; Waki, N.; Nakano, T.; Asai, H.; Yonezawa, T.; Kitamura, Y.

    1988-01-01

    Two different types of cells in the peritoneal cavity of mice produce mast cell colonies in methylcellulose. Large mast cell colonies are produced by bone marrow-derived precursors resembling lymphoid cells by light microscopy (L-CFU-Mast), whereas medium and small mast cell colonies are produced by morphologically identifiable mast cells (M-CFU-Mast and S-CFU-Mast, respectively). In the present study we eradicated peritoneal mast cells by intraperitoneal (IP) injection of distilled water. The regeneration process was investigated to clarify the relationship between L-CFU-Mast, M-CFU-Mast, and S-CFU-Mast. After injection of distilled water, M-CFU-Mast and S-CFU-Mast disappeared, but L-CFU-Mast increased, and then M-CFU-Mast and S-CFU-Mast appeared, suggesting the presence of a hierarchic relationship. When purified peritoneal mast cells were injected two days after the water injection, the L-CFU-Mast did not increase. In the peritoneal cavity of WBB6F1-+/+ mice that had been lethally irradiated and rescued by bone marrow cells of C57BL/6-bgJ/bgJ (beige, Chediak-Higashi syndrome) mice, L-CFU-Mast were of bgJ/bgJ type, but M-CFU-Mast and S-CFU-Mast were of +/+ type. The injection of distilled water to the radiation chimeras resulted in the development of bgJ/bgJ-type M-CFU-Mast and then S-CFU-Mast. The presence of mast cells appeared to suppress the recruitment of L-CFU-Mast from the bloodstream and to inhibit the differentiation of L-CFU-Mast to M-CFU-Mast

  19. Impedimetric quantification of the formation process and the chemosensitivity of cancer cell colonies suspended in 3D environment.

    Science.gov (United States)

    Lei, Kin Fong; Wu, Zong-Ming; Huang, Chia-Hao

    2015-12-15

    In cancer research, colony formation assay is a gold standard for the investigation of the development of early tumors and the effects of cytotoxic agents on tumors in vitro. Quantification of cancer cell colonies suspended in hydrogel is currently achieved by manual counting under microscope. It is challenging to microscopically quantify the colony number and size without subjective bias. In this work, impedimetric quantification of cancer cell colonies suspended in hydrogel was successfully developed and provides a quantitative and objective method to describe the colony formation process and the development of colony size during the culture course. A biosensor embedded with a pair of parallel plate electrodes was fabricated for the impedimetric quantification. Cancer cell (cell line: Huh-7) were encapsulated in methyl cellulose hydrogel and cultured to gradually form cancer cell colonies suspended in 3D environment. At pre-set schedule during the culture course, small volume (50 μL) of colonies/MC hydrogel was collected, mixed with measurement hydrogel, and loaded to the biosensor for measurement. Hence, the colony formation process could be quantitatively represented by a colony index and a colony size index calculated from electrical impedance. Based on these developments, chemosensitivity of cancer cell colonies under different concentrations of anti-cancer drug, i.e., doxorubicin, was quantitatively investigated to study the efficacy of anti-cancer drug. Also, dose-response curve was constructed to calculate the IC50 value, which is an important indicator for chemosensitivity assay. These results showed the impedimetric quantification is a promising technique for the colony formation assay. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Morphology and dynamics of tumor cell colonies propagating in epidermal growth factor supplemented media

    Science.gov (United States)

    Muzzio, N. E.; Carballido, M.; Pasquale, M. A.; González, P. H.; Azzaroni, O.; Arvia, A. J.

    2018-07-01

    The epidermal growth factor (EGF) plays a key role in physiological and pathological processes. This work reports on the influence of EGF concentration (c EGF) on the modulation of individual cell phenotype and cell colony kinetics with the aim of perturbing the colony front roughness fluctuations. For this purpose, HeLa cell colonies that remain confluent along the whole expansion process with initial quasi-radial geometry and different initial cell populations, as well as colonies with initial quasi-linear geometry and large cell population, are employed. Cell size and morphology as well as its adhesive characteristics depend on c EGF. Quasi-radial colonies (QRC) expansion kinetics in EGF-containing medium exhibits a complex behavior. Namely, at the first stages of growth, the average QRC radius evolution can be described by a t 1/2 diffusion term coupled with exponential growth kinetics up to a critical time, and afterwards a growth regime approaching constant velocity. The extension of each regime depends on c EGF and colony history. In the presence of EGF, the initial expansion of quasi-linear colonies (QLCs) also exhibits morphological changes at both the cell and the colony levels. In these cases, the cell density at the colony border region becomes smaller than in the absence of EGF and consequently, the extension of the effective rim where cell duplication and motility contribute to the colony expansion increases. QLC front displacement velocity increases with c EGF up to a maximum value in the 2–10 ng ml‑1 range. Individual cell velocity is increased by EGF, and an enhancement in both the persistence and the ballistic characteristics of cell trajectories can be distinguished. For an intermediate c EGF, collective cell displacements contribute to the roughening of the colony contours. This global dynamics becomes compatible with the standard Kardar–Parisi–Zhang growth model, although a faster colony roughness saturation in EGF-containing medium

  1. Video Bioinformatics Analysis of Human Embryonic Stem Cell Colony Growth

    Science.gov (United States)

    Lin, Sabrina; Fonteno, Shawn; Satish, Shruthi; Bhanu, Bir; Talbot, Prue

    2010-01-01

    Because video data are complex and are comprised of many images, mining information from video material is difficult to do without the aid of computer software. Video bioinformatics is a powerful quantitative approach for extracting spatio-temporal data from video images using computer software to perform dating mining and analysis. In this article, we introduce a video bioinformatics method for quantifying the growth of human embryonic stem cells (hESC) by analyzing time-lapse videos collected in a Nikon BioStation CT incubator equipped with a camera for video imaging. In our experiments, hESC colonies that were attached to Matrigel were filmed for 48 hours in the BioStation CT. To determine the rate of growth of these colonies, recipes were developed using CL-Quant software which enables users to extract various types of data from video images. To accurately evaluate colony growth, three recipes were created. The first segmented the image into the colony and background, the second enhanced the image to define colonies throughout the video sequence accurately, and the third measured the number of pixels in the colony over time. The three recipes were run in sequence on video data collected in a BioStation CT to analyze the rate of growth of individual hESC colonies over 48 hours. To verify the truthfulness of the CL-Quant recipes, the same data were analyzed manually using Adobe Photoshop software. When the data obtained using the CL-Quant recipes and Photoshop were compared, results were virtually identical, indicating the CL-Quant recipes were truthful. The method described here could be applied to any video data to measure growth rates of hESC or other cells that grow in colonies. In addition, other video bioinformatics recipes can be developed in the future for other cell processes such as migration, apoptosis, and cell adhesion. PMID:20495527

  2. Leukemic blast cell colony formation in semisolid culture with erythropoietin: a case report of acute poorly differentiated erythroid leukemia.

    Science.gov (United States)

    Tomonaga, M; Jinnai, I; Tagawa, M; Amenomori, T; Nishino, K; Yao, E; Nonaka, H; Kuriyama, K; Yoshida, Y; Matsuo, T

    1987-02-01

    The bone marrow of a patient with acute undifferentiated leukemia developed unique colonies after a 14-day culture in erythropoietin (EPO)-containing methylcellulose. The colonies consisted of 20 to 200 nonhemoglobinized large blast cells. Cytogenetic analysis of single colonies revealed hypotetraploid karyotypes with several marker chromosomes that were identical to those found in directly sampled bone marrow. The concurrently formed erythroid bursts showed only normal karyotypes. No leukemic colony formation was observed in other culture systems with either colony-stimulating activity (CSA) or phytohemagglutinin-stimulated leukocyte-conditioned medium (PHA-LCM). The leukemic colonies exhibited a complete EPO-dose dependency similar to that of the patient's normal BFU-E. Although cytochemical and immunologic marker studies of the bone marrow cells failed to clarify the cell lineage of the leukemic cells with extraordinarily large cell size, ultrastructural study revealed erythroid differentiation such as siderosome formation in the cytoplasm and ferritin particles in the rhophecytosis invaginations. These findings indicate that the patient had poorly differentiated erythroid leukemia and that some of the clonogenic cells might respond to EPO in vitro. Corresponding to this biological feature, the leukemic cells were markedly decreased in number in response to repeated RBC transfusions, and partial remission was obtained. These observations suggest that erythroid leukemia distinct from erythroleukemia (M6) with a myeloblastic component, can develop as a minor entity of human acute leukemia.

  3. High-Throughput Quantification of Bacterial-Cell Interactions Using Virtual Colony Counts

    Directory of Open Access Journals (Sweden)

    Stefanie Hoffmann

    2018-02-01

    Full Text Available The quantification of bacteria in cell culture infection models is of paramount importance for the characterization of host-pathogen interactions and pathogenicity factors involved. The standard to enumerate bacteria in these assays is plating of a dilution series on solid agar and counting of the resulting colony forming units (CFU. In contrast, the virtual colony count (VCC method is a high-throughput compatible alternative with minimized manual input. Based on the recording of quantitative growth kinetics, VCC relates the time to reach a given absorbance threshold to the initial cell count using a series of calibration curves. Here, we adapted the VCC method using the model organism Salmonella enterica sv. Typhimurium (S. Typhimurium in combination with established cell culture-based infection models. For HeLa infections, a direct side-by-side comparison showed a good correlation of VCC with CFU counting after plating. For MDCK cells and RAW macrophages we found that VCC reproduced the expected phenotypes of different S. Typhimurium mutants. Furthermore, we demonstrated the use of VCC to test the inhibition of Salmonella invasion by the probiotic E. coli strain Nissle 1917. Taken together, VCC provides a flexible, label-free, automation-compatible methodology to quantify bacteria in in vitro infection assays.

  4. Chromosome aberrations and cell survival in irradiated mammalian cells

    International Nuclear Information System (INIS)

    Tremp, J.

    1981-01-01

    A possible correlation between chromosome aberrations and reduced proliferation capacity or cell death was investigated. Synchronized Chinese hamster fibroblast cells were irradiated with 300 rad of x rays in early G 1 . Despite synchronization the cells reached the subsequent mitosis at different times. The frequency of chromosome aberrations was determined in the postirradiation division at 2-h intervals. The highest frequency occurred in cells with a first cell cycle of medium length. The colony-forming ability of mitotic cells was measured in parallel samples by following the progress of individual mitoses. The proportion of cells forming macrocolonies decreased with increasing cell cycle length, and the number of non-colony-forming cells increased. Irrespective of various first cell cycle lengths and different frequencies of chromosome aberrations, the number of cells forming microcolonies remained constant. A correlation was found between the absence of chromosome aberrations and the ability of cells to form macrocolonies. However, cells with a long first cell cycle formed fewer macrocolonies than expected

  5. Culture on fibrin matrices maintains the colony-forming capacity and osteoblastic differentiation of mesenchymal stem cells

    International Nuclear Information System (INIS)

    Colley, Helen; McArthur, Sally L; Stolzing, Alexandra; Scutt, Andy

    2012-01-01

    Mesenchymal stem cells (MSC) are multipotent cells capable of differentiating into a number of mesenchymal tissues including bone, cartilage, and tendon. Low numbers in vivo means exponential growth is needed in culture to enable therapeutic applications. MSC can expand rapidly in culture but usually lose their extensive capacity for differentiation that makes them therapeutically attractive. To try and maintain their capacity for differentiation and expansion in vitro, we cultured MSC on fibrin gels of different concentrations to create more physiological growth conditions for the cells. The cells were then re-plated onto tissue culture plastic and analysed. The cells that had been pre-cultured for seven days on fibrin, proliferated and maintained their differential potential to the osteogenic lineage better than tissue culture plastic expanded MSC. A concentration relationship between colony number and fibrin concentration was seen with decreasing numbers as fibrin concentration increased. These data support the concept that substrate signals significantly influence MSC growth and differentiation and that growth on a fibrin matrix could be used to maintain a stem cell phenotype during MSC expansion. (paper)

  6. Determination of the stem cell number by the amount of nondifferentiated cell colonies in the bone marrow of irradiated animals

    International Nuclear Information System (INIS)

    Shcherbova, E.N.; Gruzdev, G.P.

    1982-01-01

    A method is proposed for determination of the amout of haemopoietic stem cells in different mammalian species according to the number of nondifferentiated cell colonies (NCC) formed in the bone marrow on days 3 or 4 after irradiation. A quantitative similarity of NCC and haemopoietic stem cells, and also sameness of their reaction to irradiation were demonstated by determining the NCC number in histological preparations of the bone marrow and by the use of the Till and McCulloch method. A method is proposed for the deter-- mination and calculation of the number of NCC in the bone marrow

  7. Determination of the stem cell number by the amount of nondifferentiated cell colonies in the bone marrow of irradiated animals

    Energy Technology Data Exchange (ETDEWEB)

    Shcherbova, E.N.; Gruzdev, G.P.

    A method is proposed for determination of the amout of haemopoietic stem cells in different mammalian species according to the number of nondifferentiated cell colonies (NCC) formed in the bone marrow on days 3 or 4 after irradiation. A quantitative similarity of NCC and haemopoietic stem cells, and also sameness of their reaction to irradiation were demonstated by determining the NCC number in histological preparations of the bone marrow and by the use of the Till and McCulloch method. A method is proposed for the determination and calculation of the number of NCC in the bone marrow.

  8. Patterns of proliferation and differentiation of irradiated haemopoietic stem cells cultured on normal 'stromal' cell colonies in vitro

    International Nuclear Information System (INIS)

    Mori, K.J.

    1981-01-01

    Experiments were designed to elucidate whether or not the irradiated bone marrow cells receive any stimulation for the self-replication and differentiation from normal 'stromal' cell colonies in the bone marrow cell culture in vitro. When irradiated or unirradiated bone marrow cells were overlaid on the normal adherent cell colonies, the proliferation of haemopoietic stem cells was supported, the degree of the stimulation depending on the starting cellular concentration. There was, however, no significant changes in the concentration of either CFUs or CFUc regardless of the dose of irradiation on the bone marrow cells overlaid. This was a great contrast to the dose-dependent decrease of CFUs or CFUc within the culture in which both the stem cells and stromal cells were simultaneously irradiated. These results suggest that the balance of self-replication and differentiation of the haemopoietic stem cells is affected only when haemopoietic microenvironment is perturbed. (author)

  9. Application of Artificial Bee Colony in Model Parameter Identification of Solar Cells

    Directory of Open Access Journals (Sweden)

    Rongjie Wang

    2015-07-01

    Full Text Available The identification of values of solar cell parameters is of great interest for evaluating solar cell performances. The algorithm of an artificial bee colony was used to extract model parameters of solar cells from current-voltage characteristics. Firstly, the best-so-for mechanism was introduced to the original artificial bee colony. Then, a method was proposed to identify parameters for a single diode model and double diode model using this improved artificial bee colony. Experimental results clearly demonstrate the effectiveness of the proposed method and its superior performance compared to other competing methods.

  10. The effects of electrospun substrate-mediated cell colony morphology on the self-renewal of human induced pluripotent stem cells.

    Science.gov (United States)

    Maldonado, Maricela; Wong, Lauren Y; Echeverria, Cristina; Ico, Gerardo; Low, Karen; Fujimoto, Taylor; Johnson, Jed K; Nam, Jin

    2015-05-01

    The development of xeno-free, chemically defined stem cell culture systems has been a primary focus in the field of regenerative medicine to enhance the clinical application of pluripotent stem cells (PSCs). In this regard, various electrospun substrates with diverse physiochemical properties were synthesized utilizing various polymer precursors and surface treatments. Human induced pluripotent stem cells (IPSCs) cultured on these substrates were characterized by their gene and protein expression to determine the effects of the substrate physiochemical properties on the cells' self-renewal, i.e., proliferation and the maintenance of pluripotency. The results showed that surface chemistry significantly affected cell colony formation via governing the colony edge propagation. More importantly, when surface chemistry of the substrates was uniformly controlled by collagen conjugation, the stiffness of substrate was inversely related to the sphericity, a degree of three dimensionality in colony morphology. The differences in sphericity subsequently affected spontaneous differentiation of IPSCs during a long-term culture, implicating that the colony morphology is a deciding factor in the lineage commitment of PSCs. Overall, we show that the capability of controlling IPSC colony morphology by electrospun substrates provides a means to modulate IPSC self-renewal. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Lysophosphatidic Acid Upregulates Laminin-332 Expression during A431 Cell Colony Dispersal

    Directory of Open Access Journals (Sweden)

    Hironobu Yamashita

    2010-01-01

    Full Text Available Lysophosphatidic acid (LPA is a bioactive phospholipid that affects various biological functions, such as cell proliferation, migration, survival, wound healing, and tumor invasion through LPA receptors. Previously, we reported that LPA induces A431 colony dispersal, accompanied by disruption of cell-cell contacts and cell migration. However, it remains unclear how LPA affects cell migration and gene expression during A431 colony dispersal. In this paper, we performed cDNA microarray analysis to investigate this question by comparing gene expression between untreated and LPA-treated A431 cells. Interestingly, these results revealed that LPA treatment upregulates several TGF-β1 target genes, including laminin-332 (Ln-332 components (α3, β3, and γ2 chains. Western blot analysis also showed that LPA increased phosphorylation of Smad2, an event that is carried out by TGF-β1 interactions. Among the genes upregulated, we further addressed the role of Ln-332. Real-time PCR analysis confirmed the transcriptional upregulation of all α3, β3, and γ2 chains of Ln-332 by LPA, corresponding to the protein level increases revealed by western blot. Further, the addition of anti-Ln-332 antibody prevented LPA-treated A431 colonies from dispersing. Taken together, our results suggest that LPA-induced Ln-332 plays a significant role in migration of individual cells from A431 colonies.

  12. Stimulation and support of haemopoietic stem cell proliferation by irradiated stroma cell colonies in bone marrow cell culture in vitro

    International Nuclear Information System (INIS)

    Mori, K.J.; Izumi, Hiroko; Seto, Akira

    1981-01-01

    A culture system was established in which haemopoietic stem cells can undergo a recovery proliferation after a depletion of the stem cells, completely in vitro. To elucidate the source of the stimulatory factors, normal bone marrow cells were overlayed on top of the irradiated adherent 'stromal' cell colonies in the bone marrow cell culture. This stimulated the proliferation of haemopoietic stem cells in the cultured cells in suspension. The present results indicate that the stromal cells produce factors which stimulate stem cell proliferation. Whether the stimulation is evoked by direct cell-cell interactions or by humoral factors is as yet to be studied. (author)

  13. Cell colony formation induced by Xenopus egg extract as a marker for improvement of cloned blastocyst formation in pig

    DEFF Research Database (Denmark)

    Liu, Ying; Østrup, Olga; Li, Juan

    2011-01-01

    method based on the colony formation of cells after extract treatment, and subsequent in vitro cloning efficiency using treated cells as chromatin donors. Porcine fetal fibroblasts were treated with each batch of extract, and cultured in embryonic stem cell (ES) medium for 12 days. The number of forming...

  14. In vitro assays for cobblestone area-forming cells, LTC-IC, and CFU-C

    NARCIS (Netherlands)

    van Os, Ronald P; Dethmers-Ausema, Bertien; de Haan, Gerald; Bunting, Kevin

    2008-01-01

    Various assays exist that measure the function of hematopoietic stemcells (HSCs). In this chapter, in vitro assays are described that measure the frequency of progenitors (colony-forming unit in culture; CFU-C), stem cells (long-term culture-initiating cell; LTC-IC), or both (cobblestone

  15. Reduced proliferation of endothelial colony-forming cells in unprovoked venous thromboembolic disease as a consequence of endothelial dysfunction

    Science.gov (United States)

    Hernandez-Lopez, Rubicel; Chavez-Gonzalez, Antonieta; Torres-Barrera, Patricia; Moreno-Lorenzana, Dafne; Lopez-DiazGuerrero, Norma; Santiago-German, David; Isordia-Salas, Irma; Smadja, David; C. Yoder, Mervin; Majluf-Cruz, Abraham

    2017-01-01

    Background Venous thromboembolic disease (VTD) is a public health problem. We recently reported that endothelial colony-forming cells (ECFCs) derived from endothelial cells (EC) (ECFC-ECs) from patients with VTD have a dysfunctional state. For this study, we proposed that a dysfunctional status of these cells generates a reduction of its proliferative ability, which is also associated with senescence and reactive oxygen species (ROS). Methods and results Human mononuclear cells (MNCs) were obtained from peripheral blood from 40 healthy human volunteers (controls) and 50 patients with VTD matched by age (20−50 years) and sex to obtain ECFCs. We assayed their proliferative ability with plasma of patients and controls and supernatants of cultures from ECFC-ECs, senescence-associated β-galactosidase (SA-β-gal), ROS, and expression of ephrin-B2/Eph-B4 receptor. Compared with cells from controls, cells from VTD patients showed an 8-fold increase of ECFCs that emerged 1 week earlier, reduced proliferation at long term (39%) and, in passages 4 and 10, a highly senescent rate (30±1.05% vs. 91.3±15.07%, respectively) with an increase of ROS and impaired expression of ephrin-B2/Eph-4 genes. Proliferation potential of cells from VTD patients was reduced in endothelial medium [1.4±0.22 doubling population (DP)], control plasma (1.18±0.31 DP), or plasma from VTD patients (1.65±0.27 DP). Conclusions As compared with controls, ECFC-ECs from individuals with VTD have higher oxidative stress, proliferation stress, cellular senescence, and low proliferative potential. These findings suggest that patients with a history of VTD are ECFC-ECs dysfunctional that could be associated to permanent risk for new thrombotic events. PMID:28910333

  16. Quantitative assay for the number of leukemic spleen colony forming unit in radiation-induced murine myeloid leukemia

    Energy Technology Data Exchange (ETDEWEB)

    Nara, N [Tokyo Medical and Dental Univ. (Japan). School of Medicine; Bessho, M

    1981-11-01

    In mice with myelogenous leukemia, leukemic spleen colony forming units were assayed quantitatively. When 5 x 10/sup 3/ - 2 x 10/sup 4/ leukemic cells were transplanted to other mice of the same strain, a rectilinear relationship (p < 0.01) was found between the number of the cells transplanted and that of the colonies formed on the surface of the spleen. From these results, the authors considered that myelogenous leukemia in mice is an adequate model for acute myelogenous leukemia in human adults, and that the quantitative assay of the leukemic colony forming units can be used for sensitivity tests of antileukemic agents.

  17. Tritiated thymidine and deoxycytidine suicide of mouse hemopoietic colony forming cells (CFC)

    International Nuclear Information System (INIS)

    Uyeki, E.M.; Wierzba, K.; Bisel, T.U.

    1981-01-01

    Significant enhancement of tritiated dCyd suicide occurred when unlabelled dThd was added to cultures of mouse monocytic colony-forming cells. Incorporation experiments supported the suicide experiments in that incorporation of tritiated dCyd into DNA was significantly increased. One hundred micromolar dCyd significantly reduced the radiotoxicity of 0.3 μCi of tritiated dThd; incorporation experiments indicated a dose-related reduction in the incorporation of tritiated dThd into DNA with the addition of 1-100 μM unlabelled dCyd. The addition of 1 μM aminopterin reversed the effect of 100 μM deoxycytidine; viz., incorporation of dThd into DNA was 90% of controls. Aminopterin had a similar effect on deoxyuridine reversal of tritiated dThd incorporation into DNA. Aminopterin had no effect on the reduction of tritiated dThd incorporation into DNA due to the addition of 100 μM unlabelled thymidine. Unlabelled ribonucleosides, Urd and Cyd, did not significantly affect the suicide pattern of tritiated dThd or dCyd when they were added to CFC cultures. Unlabelled deoxyribonucleosides, dThd or dCyd, did not significantly affect the suicide pattern of either tritiated Cyd or Urd when they were added to cultures containing tritiated ribonucleosides. Unlabelled Urd or Cyd was effective in reversing the suicide due to tritiated Urd or Cyd. (author)

  18. Defibrotide in combination with granulocyte colony-stimulating factor significantly enhances the mobilization of primitive and committed peripheral blood progenitor cells in mice.

    Science.gov (United States)

    Carlo-Stella, Carmelo; Di Nicola, Massimo; Magni, Michele; Longoni, Paolo; Milanesi, Marco; Stucchi, Claudio; Cleris, Loredana; Formelli, Franca; Gianni, Massimo A

    2002-11-01

    Defibrotide is a polydeoxyribonucleotide, which significantly reduces the expression of adhesion molecules on endothelial cells. We investigated the activity of Defibrotide alone or in combination with recombinant human granulocyte colony-stimulating factor (rhG-CSF) to mobilize peripheral blood progenitor cells (PBPCs) in BALB/c mice. A 5-day treatment with Defibrotide alone (1-15 mg/mouse/day) had no effect on WBC counts, frequencies and absolute numbers of total circulating colony-forming cells (CFCs), i.e., granulocyte-macrophage colony-forming units, erythroid burst-forming units, and multilineage colony-forming units. As compared with mock-injected mice, administration of rhG-CSF alone (5 micro g/mouse/day) for 5 days significantly (P Defibrotide (15 mg/mouse/day) and rhG-CSF significantly (P Defibrotide plus rhG-CSF resulted in a significant increase (P Defibrotide/rhG-CSF-mobilized mononuclear cells rescued 43% and 71% of recipient mice, respectively. Experiments of CFC homing performed in lethally irradiated or nonirradiated recipients showed that marrow homing of transplanted PBPCs was reduced by 3-fold in Defibrotide-treated animals as compared with mock-injected mice (P Defibrotide might be because of an effect on PBPC trafficking. In conclusion, our data demonstrate that Defibrotide synergizes with rhG-CSF and significantly increases the mobilization of a broad spectrum of PBPCs, including primitive and committed progenitor cells. These data might have relevant implications for autologous and allogeneic anticancer therapy in humans.

  19. Contact enhancement of locomotion in spreading cell colonies

    Science.gov (United States)

    D'Alessandro, Joseph; Solon, Alexandre P.; Hayakawa, Yoshinori; Anjard, Christophe; Detcheverry, François; Rieu, Jean-Paul; Rivière, Charlotte

    2017-10-01

    The dispersal of cells from an initially constrained location is a crucial aspect of many physiological phenomena, ranging from morphogenesis to tumour spreading. In such processes, cell-cell interactions may deeply alter the motion of single cells, and in turn the collective dynamics. While contact phenomena like contact inhibition of locomotion are known to come into play at high densities, here we focus on the little explored case of non-cohesive cells at moderate densities. We fully characterize the spreading of micropatterned colonies of Dictyostelium discoideum cells from the complete set of individual trajectories. From data analysis and simulation of an elementary model, we demonstrate that contact interactions act to speed up the early population spreading by promoting individual cells to a state of higher persistence, which constitutes an as-yet unreported contact enhancement of locomotion. Our findings also suggest that the current modelling paradigm of memoryless active particles may need to be extended to account for the history-dependent internal state of motile cells.

  20. The Effects of Sertoli Cells Condition Medium and Retinoic Acid on the Number of Colonies of Bone Marrow Mesenchymal Stem Cells

    Directory of Open Access Journals (Sweden)

    Maryam Salem

    2017-04-01

    Full Text Available Background & objectives: According to importance of bone marrow mesenchymal stem cells in production of different cell lines, transplantation of these cells are used for treatment of many different diseases during cell therapy. Viability and proliferation of these cells after transplantation are very important. Since infertility is as public health problem in men and women, the scientists attempt to produce germ cells from differentiation of stem cells. It is supposed to use these cells for treatment of different illnesses especially for men with lack of germ cells in testes in future. However, in using stem cells for cell therapy the culture medium should be designed to increase the number of cells and efficiency of transplantation and to guarantee the health of the cells in terms of DNA damage. This study designed a suitable culture medium in order to increase the number of colonies and decrease the cell injuries. Methods: In this study mesenchymal stem cells isolated from bone marrow of mice and exposed to retinoic acid (RA with concentration of 10-6 M and Sertoli cells condition medium. Since mesenchymal stem cells (MSCs produce fibroblastic colonies so the number of colonies was counted every 3 days after culture (days of 2, 5, 8, 11, and 15 under inverted microscope. The staining of ethidium bromide-acridine orange was also done for determination of apoptotic nucleus in days of 10 and 15 after culture. Results: The results showed that the effects of retinoic acid on grow and viability of MSCs is related to the time. It seems that RA increased the proliferation of the cells and the number of colonies increased in low time but the apoptotic cells elevated with increasing the time of culture. Condition medium of Sertoli cells also increased the proliferation of bone marrow stem cells. Conclusion: According to proliferative properties of condition medium, it seems that using condition medium together with RA is better than RA alone for

  1. Manufacture of endothelial colony-forming progenitor cells from steady-state peripheral blood leukapheresis using pooled human platelet lysate.

    Science.gov (United States)

    Siegel, Georg; Fleck, Erika; Elser, Stefanie; Hermanutz-Klein, Ursula; Waidmann, Marc; Northoff, Hinnak; Seifried, Erhard; Schäfer, Richard

    2018-05-01

    Endothelial colony-forming progenitor cells (ECFCs) are promising candidates for cell therapies. However, ECFC translation to the clinic requires optimized isolation and manufacture technologies according to good manufacturing practice (GMP). ECFCs were manufactured from steady-state peripheral blood (PB) leukapheresis (11 donors), using GMP-compliant technologies including pooled human platelet (PLT) lysate, and compared to human umbilical cord endothelial cells, human aortic endothelial cells, and human cerebral microvascular endothelial cells. Specific variables assessed were growth kinetics, phenotype, trophic factors production, stimulation of tube formation, and Dil-AcLDL uptake. ECFCs could be isolated from PB leukapheresis units with mean processed volume of 5411 mL and mean white blood cell (WBC) concentration factor of 8.74. The mean frequency was 1.44 × 10 -8 ECFCs per WBC, corresponding to a mean of 177.8 ECFCs per apheresis unit. Expandable for up to 12 cumulative population doublings, calculated projection showed that approximately 730 × 10 3 ECFCs could be manufactured from 1 apheresis unit. ECFCs produced epidermal growth factor, hepatocyte growth factor, vascular endothelial growth factor (VEGF)-A, PLT-derived growth factor-B, interleukin-8, and monocyte chemoattractant protein-1, featured high potential for capillary-like tubes formation, and showed no telomerase activity. They were characterized by CD29, CD31, CD44, CD105, CD117, CD133, CD144, CD146, and VEGF-R2 expression, with the most common subpopulation CD34+CD117-CD133-. Compared to controls, ECFCs featured greater Dil-AcLDL uptake and higher expression of CD29, CD31, CD34, CD44, CD144, and VEGF-R2. Here we show that isolation of ECFCs with proangiogenic profile from steady-state PB leukapheresis is feasible, marking a first step toward ECFC product manufacture according to GMP. © 2018 AABB.

  2. Arsenic promotes centrosome abnormalities and cell colony formation in p53 compromised human lung cells

    International Nuclear Information System (INIS)

    Liao Weiting; Lin Pinpin; Cheng, T.-S.; Yu, H.-S.; Chang, Louis W.

    2007-01-01

    Epidemiological evidence indicated that residents, especially cigarette smokers, in arseniasis areas had significantly higher lung cancer risk than those living in non-arseniasis areas. Thus, an interaction between arsenic and cigarette smoking in lung carcinogenesis was suspected. p53 dysfunction or mutation in lung epithelial cells was frequently observed in cigarette smokers. Our present study was to explore the differential effects by arsenic on H1355 cells (human lung adenocarcinoma cell line with mutation in p53), BEAS-2B (immortalized lung epithelial cell with functional p53) and pifithrin-α-treated BEAS-2B cells (p53-inhibited cells). These cells were treated with different doses of sodium arsenite (0, 0.1, 1, 5 and 10 μM) for 48 h. A greater reduction in cell viability was observed in the BEAS-2B cells vs. p53 compromised cells (H1355 or p53-inhibited BEAS-2B). Similar observation was also made on 7-day cell survival (growth) study. TUNEL analysis confirmed that there was indeed a significantly reduced arsenite-induced apoptosis found in p53-compromised cells. Centrosomal abnormality has been attributed to eventual chromosomal missegregation, aneuploidy and tumorigenesis. In our present study, reduced p21 and Gadd45a expressions and increased centrosomal abnormality (atopic and multiple centrosomes) were observed in both arsenite-treated H1355 and p53-inhibited BEAS-2B cells as compared with similarly treated BEAS-2B cells. Increased anchorage-independent growth (colony formation) of BEAS-2B cells co-treated with pifithrin-α and 5 μM sodium arsenite was also observed in soft agar. Our present investigation demonstrated that arsenic would act specifically on p53 compromised cells (either with p53 dysfunction or inhibited) to induce centrosomal abnormality and colony formation. These findings provided strong evidence on the carcinogenic promotional role of arsenic, especially under the condition of p53 dysfunction

  3. Area-based cell colony surviving fraction evaluation: A novel fully automatic approach using general-purpose acquisition hardware.

    Science.gov (United States)

    Militello, Carmelo; Rundo, Leonardo; Conti, Vincenzo; Minafra, Luigi; Cammarata, Francesco Paolo; Mauri, Giancarlo; Gilardi, Maria Carla; Porcino, Nunziatina

    2017-10-01

    The current methodology for the Surviving Fraction (SF) measurement in clonogenic assay, which is a technique to study the anti-proliferative effect of treatments on cell cultures, involves manual counting of cell colony forming units. This procedure is operator-dependent and error-prone. Moreover, the identification of the exact colony number is often not feasible due to the high growth rate leading to the adjacent colony merging. As a matter of fact, conventional assessment does not deal with the colony size, which is generally correlated with the delivered radiation dose or the administered cytotoxic agent. Considering that the Area Covered by Colony (ACC) is proportional to the colony number and size as well as to the growth rate, we propose a novel fully automatic approach exploiting Circle Hough Transform, to automatically detect the wells in the plate, and local adaptive thresholding, which calculates the percentage of ACC for the SF quantification. This measurement relies just on this covering percentage and does not consider the colony number, preventing inconsistencies due to intra- and inter-operator variability. To evaluate the accuracy of the proposed approach, we compared the SFs obtained by our automatic ACC-based method against the conventional counting procedure. The achieved results (r = 0.9791 and r = 0.9682 on MCF7 and MCF10A cells, respectively) showed values highly correlated with the measurements using the traditional approach based on colony number alone. The proposed computer-assisted methodology could be integrated in laboratory practice as an expert system for the SF evaluation in clonogenic assays. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. vasa-related genes and their expression in stem cells of colonial parasitic rhizocephalan barnacle Polyascus polygenea (Arthropoda: Crustacea: Cirripedia: Rhizocephala).

    Science.gov (United States)

    Shukalyuk, Andrey I; Golovnina, Kseniya A; Baiborodin, Sergei I; Gunbin, Konstantin V; Blinov, Alexander G; Isaeva, Valeria V

    2007-02-01

    vasa (vas)-related genes are members of the DEAD-box protein family and are expressed in the germ cells of many Metazoa. We cloned vasa-related genes (PpVLG, CpVLG) and other DEAD-box family related genes (PpDRH1, PpDRH2, CpDRH, AtDRHr) from the colonial parasitic rhizocephalan barnacle Polyascus polygenea, the non-colonial Clistosaccus paguri (Crustacea: Cirripedia: Rhizocephala), and the parasitic isopodan Athelgis takanoshimensis (Crustacea: Isopoda). The colonial Polyascus polygenea, a parasite of the coastal crabs Hemigrapsus sanguineus and Hemigrapsus longitarsis was used as a model object for further detailed investigations. Phylogenetic analysis suggested that PpVLG and CpVLG are closely related to vasa-like genes of other Arthropoda. The rest of the studied genes form their own separate branch on the phylogenetic tree and have a common ancestry with the p68 and PL10 subfamilies. We suppose this group may be a new subfamily of the DEAD-box RNA helicases that is specific for parasitic Crustacea. We found PpVLG and PpDRH1 expression products in stem cells from stolons and buds of internae, during asexual reproduction of colonial P. polygenea, and in germ cells from sexually reproducing externae, including male spermatogenic cells and female oogenic cells.

  5. Agar Technique for the Cultivation In Vitro of Bone-Marrow Colonies

    Energy Technology Data Exchange (ETDEWEB)

    Metcalf, D. [Walter and Eliza Hall Institute, Royal Melbourne Hospital, Melbourne, VIC (Australia)

    1969-07-15

    In solid-state agar cultures certain haemopoietic cells proliferate and form discrete colonies of 200 - 4000 cells. Colony formation is dependent on stimulation by the colony-stimulating factor, and this is achieved by (1) the use of a cell feeder layer, (2) the addition of conditioned medium, or (3) the addition of human or mouse serum or urine containing the factor. All colonies initially contain granulocytic cells which differentiate from myeloblasts to polymorphs as colony growth proceeds. Later colonies develop a second population of phagocytic mononuclear cells (macrophages). The colony-forming-system is simple, readily quantitated and highly reproducible. Linear dose responses occur between the dose of colony-stimulating factor and the number and size of colonies developing from a standard number of bone-marrow cells. In-vitro colony formation has been achieved with haemopoietic cells of the following species: mouse, rat, hamster, guinea pig, rabbit and human. In the adult mouse, colony-forming cells are located in the bone marrow, spleen and blood and in the embryo, in the yolk sac, liver and spleen. The colony-forming cell appears to be an early member of the granulocytic series. The colony-forming system has been used as a quantitative assay system: (1) to assay levels of colony-stimulating factor in serum and urine and in the chemical- characterization and purification of the factor; and (2) to enumerate the number of colony-forming cells in haemopoietic tissues in response to a variety of experimental procedures and disease states. Since the system is applicable to human bone-marrow cells, it should prove of value in the quantitative assay of (1) survival of human bone marrow on storage, and (2) bone-marrow content of granulocytic precursor cells in various disease states and following various types of therapy. The system is not suitable for the mass production in vitro of haemopoietic cells for therapeutic use. (author)

  6. Granulocyte colony-stimulating factor mobilizes functional endothelial progenitor cells in patients with coronary artery disease.

    Science.gov (United States)

    Powell, Tiffany M; Paul, Jonathan D; Hill, Jonathan M; Thompson, Michael; Benjamin, Moshe; Rodrigo, Maria; McCoy, J Philip; Read, Elizabeth J; Khuu, Hanh M; Leitman, Susan F; Finkel, Toren; Cannon, Richard O

    2005-02-01

    Endothelial progenitor cells (EPCs) that may repair vascular injury are reduced in patients with coronary artery disease (CAD). We reasoned that EPC number and function may be increased by granulocyte colony-stimulating factor (G-CSF) used to mobilize hematopoietic progenitor cells in healthy donors. Sixteen CAD patients had reduced CD34(+)/CD133(+) (0.0224+/-0.0063% versus 0.121+/-0.038% mononuclear cells [MNCs], P<0.01) and CD133(+)/VEGFR-2(+) cells, consistent with EPC phenotype (0.00033+/-0.00015% versus 0.0017+/-0.0006% MNCs, P<0.01), compared with 7 healthy controls. Patients also had fewer clusters of cells in culture, with out-growth consistent with mature endothelial phenotype (2+/-1/well) compared with 16 healthy subjects at high risk (13+/-4/well, P<0.05) or 14 at low risk (22+/-3/well, P<0.001) for CAD. G-CSF 10 microg/kg per day for 5 days increased CD34(+)/CD133(+) cells from 0.5+/-0.2/microL to 59.5+/-10.6/microL and CD133(+)/ VEGFR-2(+) cells from 0.007+/-0.004/microL to 1.9+/-0.6/microL (both P<0.001). Also increased were CD133(+) cells that coexpressed the homing receptor CXCR4 (30.4+/-8.3/microL, P<0.05). Endothelial cell-forming clusters in 10 patients increased to 27+/-9/well after treatment (P<0.05), with a decline to 9+/-4/well at 2 weeks (P=0.06). Despite reduced EPCs compared with healthy controls, patients with CAD respond to G-CSF with increases in EPC number and homing receptor expression in the circulation and endothelial out-growth in culture. Endothelial progenitor cells (EPCs) are reduced in coronary artery disease. Granulocyte colony-stimulating factor (CSF) administered to patients increased: (1) CD133+/VEGFR-2+ cells consistent with EPC phenotype; (2) CD133+ cells coexpressing the chemokine receptor CXCR4, important for homing of EPCs to ischemic tissue; and (3) endothelial cell-forming clusters in culture. Whether EPCs mobilized into the circulation will be useful for the purpose of initiating vascular growth and myocyte repair

  7. Observations of radiation-induced chromosome fragment loss in live mammalian cells in culture, and its effect on colony-forming ability

    International Nuclear Information System (INIS)

    Grote, S.J.; Joshi, G.P.; Revell, S.H.; Shaw, C.A.

    1981-01-01

    A preceding paper (Grote, Joshi, Revell and Shaw 1981) describe a method for the direct scrutiny of live cultured mammalian cells with a microscope, and reported that all diploid Syrian hamster cells (BHK 21 C13) of a sample given 1.4 Gy of 220 kV X-rays in G1 reached post-radiation mitosis without discernible abnormality, but then diverged in observed behaviour: descendant cells from some first mitoses continued to proliferate normally while cells from other first mitoses behaved abnormally and produced either slow-growth or stop-growth colonies. This paper completes the study of the same irradiated cell sample, and shows that these post-mitotic differences in clonogenic ability were related to acentric chromosome fragment losses at post-radiation mitosis, which were detected in live daughter-cell pairs as micronuclei. The proportion of live daughter-cell pairs scored as deficient was at least 80 per cent of the proportion of comparable fixed-and-stained mitoses with detected acentric fragments. (author)

  8. The Transcription Factor Nrf2 Protects Angiogenic Capacity of Endothelial Colony-Forming Cells in High-Oxygen Radical Stress Conditions

    Directory of Open Access Journals (Sweden)

    Hendrik Gremmels

    2017-01-01

    Full Text Available Background. Endothelial colony forming cells (ECFCs have shown a promise in tissue engineering of vascular constructs, where they act as endothelial progenitor cells. After implantation, ECFCs are likely to be subjected to elevated reactive oxygen species (ROS. The transcription factor Nrf2 regulates the expression of antioxidant enzymes in response to ROS. Methods. Stable knockdown of Nrf2 and Keap1 was achieved by transduction with lentiviral shRNAs; activation of Nrf2 was induced by incubation with sulforaphane (SFN. Expression of Nrf2 target genes was assessed by qPCR, oxidative stress was assessed using CM-DCFDA, and angiogenesis was quantified by scratch-wound and tubule-formation assays. Results. Nrf2 knockdown led to a reduction of antioxidant gene expression and increased ROS. Angiogenesis was disturbed after Nrf2 knockdown even in the absence of ROS. Conversely, angiogenesis was preserved in high ROS conditions after knockdown of Keap1. Preincubation of ECFCs with SFN reduced intracellular ROS in the presence of H2O2 and preserved scratch-wound closure and tubule-formation. Conclusion. The results of this study indicate that Nrf2 plays an important role in the angiogenic capacity of ECFCs, particularly under conditions of increased oxidative stress. Pretreatment of ECFCs with SFN prior to implantation may be a protective strategy for tissue-engineered constructs or cell therapies.

  9. An In Vitro Study of Differentiation of Hematopoietic Cells to Endothelial Cells

    Directory of Open Access Journals (Sweden)

    Qi Ru Wang

    2011-01-01

    medium (ECCM. BM-EPCs were characterized in terms of phenotype, lineage potential, and their functional properties. Endothelial cell colonies derived from BM-EPC were cultured with ECCM for 3 months. Cultured EPC colony cells expressed endothelial cell markers and formed the capillary-like network in vitro. EPC colony cells expressed differential proliferative capacity; some of the colonies exhibited a high proliferative potential (HPP capacity up to 20 population doublings. More importantly, these HPP-EPCs expressed hematopoietic marker CD45, exhibited endocytic activities, and preserved some of the myeloid cell activity. In addition, the HPP-EPCs secrete various growth factors including VEGF and GM-CSF into the culture medium. The results demonstrate that these EPCs were primarily derived from hematopoietic origin of early precursor cells and maintained high proliferative potential capacity, a feature with a significant potential in the application of cell therapy in ischemic diseases.

  10. The Self-Identity Protein IdsD Is Communicated between Cells in Swarming Proteus mirabilis Colonies.

    Science.gov (United States)

    Saak, Christina C; Gibbs, Karine A

    2016-12-15

    Proteus mirabilis is a social bacterium that is capable of self (kin) versus nonself recognition. Swarming colonies of this bacterium expand outward on surfaces to centimeter-scale distances due to the collective motility of individual cells. Colonies of genetically distinct populations remain separate, while those of identical populations merge. Ids proteins are essential for this recognition behavior. Two of these proteins, IdsD and IdsE, encode identity information for each strain. These two proteins bind in vitro in an allele-restrictive manner. IdsD-IdsE binding is correlated with the merging of populations, whereas a lack of binding is correlated with the separation of populations. Key questions remained about the in vivo interactions of IdsD and IdsE, specifically, whether IdsD and IdsE bind within single cells or whether IdsD-IdsE interactions occur across neighboring cells and, if so, which of the two proteins is exchanged. Here we demonstrate that IdsD must originate from another cell to communicate identity and that this nonresident IdsD interacts with IdsE resident in the recipient cell. Furthermore, we show that unbound IdsD in recipient cells does not cause cell death and instead appears to contribute to a restriction in the expansion radius of the swarming colony. We conclude that P. mirabilis communicates IdsD between neighboring cells for nonlethal kin recognition, which suggests that the Ids proteins constitute a type of cell-cell communication. We demonstrate that self (kin) versus nonself recognition in P. mirabilis entails the cell-cell communication of an identity-encoding protein that is exported from one cell and received by another. We further show that this intercellular exchange affects swarm colony expansion in a nonlethal manner, which adds social communication to the list of potential swarm-related regulatory factors. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  11. Clonogenic assay: adherent cells.

    Science.gov (United States)

    Rafehi, Haloom; Orlowski, Christian; Georgiadis, George T; Ververis, Katherine; El-Osta, Assam; Karagiannis, Tom C

    2011-03-13

    The clonogenic (or colony forming) assay has been established for more than 50 years; the original paper describing the technique was published in 1956. Apart from documenting the method, the initial landmark study generated the first radiation-dose response curve for X-ray irradiated mammalian (HeLa) cells in culture. Basically, the clonogenic assay enables an assessment of the differences in reproductive viability (capacity of cells to produce progeny; i.e. a single cell to form a colony of 50 or more cells) between control untreated cells and cells that have undergone various treatments such as exposure to ionising radiation, various chemical compounds (e.g. cytotoxic agents) or in other cases genetic manipulation. The assay has become the most widely accepted technique in radiation biology and has been widely used for evaluating the radiation sensitivity of different cell lines. Further, the clonogenic assay is commonly used for monitoring the efficacy of radiation modifying compounds and for determining the effects of cytotoxic agents and other anti-cancer therapeutics on colony forming ability, in different cell lines. A typical clonogenic survival experiment using adherent cells lines involves three distinct components, 1) treatment of the cell monolayer in tissue culture flasks, 2) preparation of single cell suspensions and plating an appropriate number of cells in petri dishes and 3) fixing and staining colonies following a relevant incubation period, which could range from 1-3 weeks, depending on the cell line. Here we demonstrate the general procedure for performing the clonogenic assay with adherent cell lines with the use of an immortalized human keratinocyte cell line (FEP-1811). Also, our aims are to describe common features of clonogenic assays including calculation of the plating efficiency and survival fractions after exposure of cells to radiation, and to exemplify modification of radiation-response with the use of a natural antioxidant

  12. Peripheral blood cells from children with RASopathies show enhanced spontaneous colonies growth in vitro and hyperactive RAS signaling

    International Nuclear Information System (INIS)

    Gaipa, G; Bugarin, C; Cianci, P; Sarno, J; Bonaccorso, P; Biondi, A; Selicorni, A

    2015-01-01

    Germline mutations in genes coding for molecules involved in the RAS/RAF/MEK/ERK pathway are the hallmarks of a newly classified family of autosomal dominant syndromes termed RASopathies. Myeloproliferative disorders (MPDs), in particular, juvenile myelomonocytic leukemia, can lead to potentially severe complications in children with Noonan syndrome (NS). We studied 27 children with NS or other RASopathies and 35 age-matched children as control subjects. Peripheral blood (PB) cells from these patients were studied for in vitro colony-forming units (CFUs) activity, as well as for intracellular phosphosignaling. Higher spontaneous growth of both burst-forming units-erythroid (BFU-E) and CFU-granulocyte/macrophage (CFU-GM) colonies from RAS-mutated patients were observed as compared with control subjects. We also observed a significantly higher amount of GM-colony-stimulating factor-induced p-ERK in children with RASopathies. Our findings demonstrate for the first time that PB cells isolated from children suffering from NS or other RASopathies without MPD display enhanced BFU-E and CFU-GM colony formation in vitro. The biological significance of these findings clearly awaits further studies. Collectively, our data provide a basis for further investigating of only partially characterized hematological alterations present in children suffering from RASopathies, and may provide new markers for progression toward malignant MPD in these patients

  13. Colony shape as a genetic trait in the pattern-forming Bacillus mycoides

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    Pisaneschi Giuseppe

    2002-11-01

    Full Text Available Abstract Background Bacillus mycoides Flügge, a Gram-positive, non-motile soil bacterium assigned to Bacillus cereus group, grows on agar as chains of cells linked end to end, forming radial filaments curving clock- or counter-clockwise (SIN or DX morphotypes. The molecular mechanism causing asymmetric curving is not known: our working hypothesis considers regulation of filamentous growth as the prerequisite for these morphotypes. Results SIN and DX strains isolated from the environment were classified as B. mycoides by biochemical and molecular biology tests. Growth on agar of different hardness and nutrient concentration did not abolish colony patterns, nor was conversion between SIN and DX morphotypes ever noticed. A number of morphotype mutants, all originating from one SIN strain, were obtained. Some lost turn direction becoming fluffy, others became round and compact. All mutants lost wild type tight aggregation in liquid culture. Growth on agar was followed by microscopy, exploring the process of colony formation and details of cell divisions. A region of the dcw (division cell wall cluster, including ftsQ, ftsA, ftsZ and murC, was sequenced in DX and SIN strains as a basis for studying cell division. This confirmed the relatedness of DX and SIN strains to the B. cereus group. Conclusions DX and SIN asymmetric morphotypes stem from a close but not identical genomic context. Asymmetry is established early during growth on agar. Wild type bacilli construct mostly uninterrupted filaments with cells dividing at the free ends: they "walk" longer distances compared to mutants, where enhanced frequency of cell separation produces new growing edges resulting in round compact colonies.

  14. Live-cell imaging of conidial anastomosis tube fusion during colony initiation in Fusarium oxysporum.

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    Smija M Kurian

    Full Text Available Fusarium oxysporum exhibits conidial anastomosis tube (CAT fusion during colony initiation to form networks of conidial germlings. Here we determined the optimal culture conditions for this fungus to undergo CAT fusion between microconidia in liquid medium. Extensive high resolution, confocal live-cell imaging was performed to characterise the different stages of CAT fusion, using genetically encoded fluorescent labelling and vital fluorescent organelle stains. CAT homing and fusion were found to be dependent on adhesion to the surface, in contrast to germ tube development which occurs in the absence of adhesion. Staining with fluorescently labelled concanavalin A indicated that the cell wall composition of CATs differs from that of microconidia and germ tubes. The movement of nuclei, mitochondria, vacuoles and lipid droplets through fused germlings was observed by live-cell imaging.

  15. From cell differentiation to cell collectives: Bacillus subtilis uses division of labor to migrate.

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    Jordi van Gestel

    2015-04-01

    Full Text Available The organization of cells, emerging from cell-cell interactions, can give rise to collective properties. These properties are adaptive when together cells can face environmental challenges that they separately cannot. One particular challenge that is important for microorganisms is migration. In this study, we show how flagellum-independent migration is driven by the division of labor of two cell types that appear during Bacillus subtilis sliding motility. Cell collectives organize themselves into bundles (called "van Gogh bundles" of tightly aligned cell chains that form filamentous loops at the colony edge. We show, by time-course microscopy, that these loops migrate by pushing themselves away from the colony. The formation of van Gogh bundles depends critically on the synergistic interaction of surfactin-producing and matrix-producing cells. We propose that surfactin-producing cells reduce the friction between cells and their substrate, thereby facilitating matrix-producing cells to form bundles. The folding properties of these bundles determine the rate of colony expansion. Our study illustrates how the simple organization of cells within a community can yield a strong ecological advantage. This is a key factor underlying the diverse origins of multicellularity.

  16. From cell differentiation to cell collectives: Bacillus subtilis uses division of labor to migrate.

    Science.gov (United States)

    van Gestel, Jordi; Vlamakis, Hera; Kolter, Roberto

    2015-04-01

    The organization of cells, emerging from cell-cell interactions, can give rise to collective properties. These properties are adaptive when together cells can face environmental challenges that they separately cannot. One particular challenge that is important for microorganisms is migration. In this study, we show how flagellum-independent migration is driven by the division of labor of two cell types that appear during Bacillus subtilis sliding motility. Cell collectives organize themselves into bundles (called "van Gogh bundles") of tightly aligned cell chains that form filamentous loops at the colony edge. We show, by time-course microscopy, that these loops migrate by pushing themselves away from the colony. The formation of van Gogh bundles depends critically on the synergistic interaction of surfactin-producing and matrix-producing cells. We propose that surfactin-producing cells reduce the friction between cells and their substrate, thereby facilitating matrix-producing cells to form bundles. The folding properties of these bundles determine the rate of colony expansion. Our study illustrates how the simple organization of cells within a community can yield a strong ecological advantage. This is a key factor underlying the diverse origins of multicellularity.

  17. Stimulated human fibroblast cell survival

    International Nuclear Information System (INIS)

    Smith, B.P.; Gale, K.L.; Einspenner, M.; Greenstock, C.L.; Gentner, N.E.

    1992-01-01

    Techniques for cloning cultured mammalian cells have supported the most universally-accepted method for measuring the induction of lethality by geno-toxicants such as ionizing radiation: the 'survival of colony-forming ability (CFA)' assay. Since most cultured human cell lines exhibit plating efficiency (i.e. the percentage of cells that are capable of reproductively surviving and dividing to form visible colonies) well below 100%, such assays are in essence 'survival of plating efficiency' assays, since they are referred to the plating (or cloning) efficiency of control (i.e. unirradiated) cells. (author). 8 refs., 2 figs

  18. Small-cell comb does not control Varroa mites in colonies of honeybees of European origin

    OpenAIRE

    Seeley , Thomas; Griffin , Sean

    2011-01-01

    International audience; We tested the idea that Varroa destructor can be controlled in colonies of the European subspecies of Apis mellifera by providing them with combs built of small cells, in which immature mites might have difficulty developing for lack of space. We established seven pairs of equal-size colonies that started out equally infested with mites. In each pair, one hive contained only standard-cell (5.4 mm) comb, and the other contained only small-cell (4.8 mm) comb. We measured...

  19. Cell cycle of spermatogonial colony forming stem cells in the CBA mouse after neutron irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Bootsma, A.L. (Rijksuniversiteit Utrecht (Netherlands). Academisch Ziekenhuis); Davids, J.A.G. (Netherlands Energy Research Foundation, Petten (Netherlands))

    1988-03-01

    In the CBA mouse testis, about 10% of the stem cell population is highly resistant to neutron irradiation (D/sub 0/, 0.75 Gy). Following a dose of 1.50 Gy these cells rapidly increase their sensitivity towards a second neutron dose and progress fairly synchronously through their first post-irradiation cell cycle. From experiments in which neutron irradiation was combined with hydroxyurea, it appeared that in this cycle the S-phase is less radiosensitive (D/sub 0/, 0.43 Gy) than the other phases of the cell cycle (D/sub 0/, 0.25 Gy). From experiments in which hydroxyurea was injected twice after irradiation, the speed of inflow of cells in S and the duration of S and the cell cycle could be calculated. Between 32 and 36 hr after irradiation cells start to enter the S-phase at a speed of 30% of the population every 12 hr. At 60 hr 50% of the population has already passed the S-phase while 30% is still in S. The data point to a cell cycle time of about 36 hr, while the S-phase lasts 12 hr at the most. (author).

  20. Acidic preconditioning of endothelial colony-forming cells (ECFC) promote vasculogenesis under proinflammatory and high glucose conditions in vitro and in vivo.

    Science.gov (United States)

    Mena, Hebe Agustina; Zubiry, Paula Romina; Dizier, Blandine; Schattner, Mirta; Boisson-Vidal, Catherine; Negrotto, Soledad

    2018-05-02

    We have previously demonstrated that acidic preconditioning of human endothelial colony-forming cells (ECFC) increased proliferation, migration, and tubulogenesis in vitro, and increased their regenerative potential in a murine model of hind limb ischemia without baseline disease. We now analyze whether this strategy is also effective under adverse conditions for vasculogenesis, such as the presence of ischemia-related toxic molecules or diabetes, one of the main target diseases for cell therapy due to their well-known healing impairments. Cord blood-derived CD34 + cells were seeded in endothelial growth culture medium (EGM2) and ECFC colonies were obtained after 14-21 days. ECFC were exposed at pH 6.6 (preconditioned) or pH 7.4 (nonpreconditioned) for 6 h, and then pH was restored at 7.4. A model of type 2 diabetes induced by a high-fat and high-sucrose diet was developed in nude mice and hind limb ischemia was induced in these animals by femoral artery ligation. A P value < 0.05 was considered statistically significant (by one-way analysis of variance). We found that acidic preconditioning increased ECFC adhesion and the release of pro-angiogenic molecules, and protected ECFC from the cytotoxic effects of monosodium urate crystals, histones, and tumor necrosis factor (TNF)α, which induced necrosis, pyroptosis, and apoptosis, respectively. Noncytotoxic concentrations of high glucose, TNFα, or their combination reduced ECFC proliferation, stromal cell-derived factor (SDF)1-driven migration, and tubule formation on a basement membrane matrix, whereas almost no inhibition was observed in preconditioned ECFC. In type 2 diabetic mice, intravenous administration of preconditioned ECFC significantly induced blood flow recovery at the ischemic limb as measured by Doppler, compared with the phosphate-buffered saline (PBS) and nonpreconditioned ECFC groups. Moreover, the histologic analysis of gastrocnemius muscles showed an increased vascular density and reduced

  1. Stem-Cell Inactivation on Transplantation of Haemopoietic Cell Suspensions from Genetically Different Donors

    Energy Technology Data Exchange (ETDEWEB)

    Petrov, R. V. [Institute of Biophysics, Ministry of Public Health of the USSR, Moscow, USSR (Russian Federation)

    1969-07-15

    The transplantation of a mixture of haemopoietic or lymphoid cells from two genetically different mice into lethally irradiated F{sub 1} recipients results in marked or total inactivation of the colony-forming units of the graft. This phenomenon is observed following transplantation of mixtures of spleen cells or bone-marrow cells from animals of different genotypes: CBA + C57BL, A + CBA, A + C57BL, C3H + C57BL, CBA + (CBA x C57BL) F{sub 1}. Maximum inactivation is observed when lymph-node cells of one genotype are transplanted with spleen or bone-marrow cells of another genotype. Use of non-syngenic kidney cells or lymphoid cells inactivated by irradiation as one component of the mixture shows that inactivation of genetically heterogeneous stem cells requires the participation of viable lymphoid cells. The inactivation phenomenon is also observed with Jerne's method. This shows that inactivation affects not only colony-forming cells but also the immunologically competent precursors of antibody-producing cells. (author)

  2. Correlation of proliferative and clonogenic tumor cells in multiple myeloma

    International Nuclear Information System (INIS)

    Karp, J.E.; Burke, P.J.; Saylor, P.L.; Humphrey, R.L.

    1984-01-01

    To expand on the findings from previous clinical trials that the growth of residual tumor is increased at a predictable time following initial drug administration, malignant plasma cells from bone marrows of patients with multiple myeloma (MM) were examined for changes in proliferation and clonogenicity induced in vivo by cyclophosphamide and in vitro by drug-induced humoral stimulatory activity. Peak plasma cell [ 3 H]thymidine labeling index (LI) occurred predictably following drug and paralleled changes in agar colony formation by marrow cells obtained during therapy. Colony-forming capacity of pretreatment MM marrow populations was enhanced when those cells were cultured with humoral stimulatory activity, similar to the increased colony formation detected in Day 9 postcyclophosphamide marrows at the time of peak plasma cell LI. To further define a relationship between proliferative plasma cells and colony-forming tumor cells, MM marrows were fractionated by sedimentation on an isokinetic gradient. Enrichment of a proliferative tumor cell cohort was achieved, evidenced by [ 3 H]thymidine LI. Colony-forming cells were also enriched by isokinetic gradient sedimentation, and agar colony formation by MM marrow cell fractions correlated with the kinetic characteristics of the isolated subpopulations. These studies of whole and fractionated human MM marrow cell populations suggest that the kinetically active cells which are induced to proliferate in vivo and in vitro are closely related to the clonogenic tumor cells which produce colonies in agar and which, like those cells measured by [ 3 H]thymidine LI, respond to growth stimulation by drug-induced humoral stimulatory activity

  3. Manipulation of the response of human endothelial colony-forming cells by focal adhesion assembly using gradient nanopattern plates.

    Science.gov (United States)

    Cui, Long-Hui; Joo, Hyung Joon; Kim, Dae Hwan; Seo, Ha-Rim; Kim, Jung Suk; Choi, Seung-Cheol; Huang, Li-Hua; Na, Ji Eun; Lim, I-Rang; Kim, Jong-Ho; Rhyu, Im Joo; Hong, Soon Jun; Lee, Kyu Back; Lim, Do-Sun

    2018-01-01

    Nanotopography plays a pivotal role in the regulation of cellular responses. Nonetheless, little is known about how the gradient size of nanostructural stimuli alters the responses of endothelial progenitor cells without chemical factors. Herein, the fabrication of gradient nanopattern plates intended to mimic microenvironment nanotopography is described. The gradient nanopattern plates consist of nanopillars of increasing diameter ranges [120-200 nm (GP 120/200), 200-280 nm (GP 200/280), and 280-360 nm (GP 280/360)] that were used to screen the responses of human endothelial colony-forming cells (hECFCs). Nanopillars with a smaller nanopillar diameter caused the cell area and perimeter of hECFCs to decrease and their filopodial outgrowth to increase. The structure of vinculin (a focal adhesion marker in hECFCs) was also modulated by nanostructural stimuli of the gradient nanopattern plates. Moreover, Rho-associated protein kinase (ROCK) gene expression was significantly higher in hECFCs cultured on GP 120/200 than in those on flat plates (no nanopillars), and ROCK suppression impaired the nanostructural-stimuli-induced vinculin assembly. These results suggest that the gradient nanopattern plates generate size-specific nanostructural stimuli suitable for manipulation of the response of hECFCs, in a process dependent on ROCK signaling. This is the first evidence of size-specific nanostructure-sensing behavior of hECFCs. Nano feature surfaces are of growing interest as materials for a controlled response of various cells. In this study, we successfully fabricated gradient nanopattern plates to manipulate the response of blood-derived hECFCs without any chemical stimulation. Interestingly, we find that the sensitive nanopillar size for manipulation of hECFCs is range between 120 nm and 200 nm, which decreased the area and increased the filopodial outgrowth of hECFCs. Furthermore, we only modulate the nanopillar size to increase ROCK expression can be an

  4. Nature of leukemic stem cells in murine myelogenous leukemia

    International Nuclear Information System (INIS)

    Yoshida, K.; Nemoto, K.; Nishimura, M.; Hayata, I.; Inoue, T.; Seki, M.

    1986-01-01

    We investigated the nature of myelogenous leukemic stem cells in mice. L-8057, a megakaryoblastic leukemia cell line used in this study, produces in vivo and in vitro colonies. By means of typical chromosomal aberrations in L-8057, one can conveniently detect the origin of the cells in each colony derived from a leukemic stem cell. Direct evidence of whether cells from each colony had leukemogenicity in recipient mice was successfully obtained by the colony transplantation assay. Both leukemic colony-forming unit-spleen (L-CFU-s) and leukemic colony-forming unit-culture (L-CFU-c) in L-8057 may have belonged to the same differentiating stage in the stem cells because of their similar radiosensitivity, although some parts of the L-CFU of L-8057 seemed to have lost their capability to regenerate L-CFU-s when the cells were plated in dishes. This leukemic stem cell preserves high self-renewal ability in vitro after 10 passages. In addition, in vitro colony formation by this leukemic cell during the above course of serial passages did not require any additional exogenous stimulators. The same sort of trials have been made on other types of leukemias. Leukemic stem cells showed remarkable variety in their response to stimulating factors and in their self-renewal activity, which suggests that they may have consisted of heterogeneous populations

  5. Differentiation of Mouse Ovarian Stem Cells Toward Oocyte-Like Structure by Coculture with Granulosa Cells.

    Science.gov (United States)

    Parvari, Soraya; Yazdekhasti, Hossein; Rajabi, Zahra; Gerayeli Malek, Valliollah; Rastegar, Tayebeh; Abbasi, Mehdi

    2016-11-01

    An increasing body of evidence has confirmed existence and function of ovarian stem cells (OSCs). In this study, a novel approach on differentiation of OSCs into oocyte-like cells (OLCs) has been addressed. Recently, different methods have been recruited to isolate and describe aspects of OSCs, but newer and more convenient strategies in isolation are still growing. Herein, a morphology-based method was used to isolate OSCs. Cell suspension of mouse neonatal ovaries was cultured and formed colonies were harvested mechanically and cultivated on mouse embryonic fibroblasts. For differentiation induction, colonies transferred on inactive granulosa cells. Results showed that cells in colonies were positive for alkaline phosphatase activity and reverse transcription-polymerase chain reaction (RT-PCR) confirmed the pluripotency characteristics of cells. Immunofluorescence revealed a positive signal for OCT4, DAZL, MVH, and SSEA1 in colonies as well. Results of RT-PCR and immunofluorescence confirmed that some OLCs were generated within the germ stem cell (GSCs) colonies. The applicability of morphological selection for isolation of GSCs was verified. This method is easier and more economic than other techniques. Our results demonstrate that granulosa cells were effective in inducing the differentiation of OSCs into OLCs through direct cell-to-cell contacts.

  6. Enhancement of the grafting efficiency of transplanted marrow cells by preincubation with interleukin-3 and granulocyte-macrophage colony-stimulating factor

    Energy Technology Data Exchange (ETDEWEB)

    Tavassoli, M.; Konno, M.; Shiota, Y.; Omoto, E.; Minguell, J.J.; Zanjani, E.D.

    1991-04-01

    To improve the grafting efficiency of transplanted murine hematopoietic progenitors, we briefly preincubated mouse bone marrow cells with interleukin-3 (IL-3) or granulocyte-macrophage colony-stimulating factor (GM-CSF) ex vivo before their transplantation into irradiated recipients. This treatment was translated into an increase in the seeding efficiency of colony-forming unit-spleen (CFU-S) and CFU-GM after transplantation. Not only was the concentration of CFU-S in the tibia increased 2 and 24 hours after transplantation, but the total cell number and CFU-S and CFU-GM concentrations were persistently higher in IL-3- and GM-CSF-treated groups 1 to 3 weeks after transplantation. In addition, the survival of animals as a function of transplanted cell number was persistently higher in IL-3- and GM-CSF-treated groups compared with controls. The data indicate that the pretreatment of marrow cells with IL-3 and GM-CSF before transplantation increases the seeding efficiency of hematopoietic stem cells and probably other progenitor cells after transplantation. This increased efficiency may be mediated by upward modulation of homing receptors. Therefore, ex vivo preincubation of donor marrow cells with IL-3 and GM-CSF may be a useful tactic in bone marrow transplantation.

  7. High frequency of endothelial colony forming cells marks a non-active myeloproliferative neoplasm with high risk of splanchnic vein thrombosis.

    Directory of Open Access Journals (Sweden)

    Vittorio Rosti

    Full Text Available Increased mobilization of circulating endothelial progenitor cells may represent a new biological hallmark of myeloproliferative neoplasms. We measured circulating endothelial colony forming cells (ECFCs in 106 patients with primary myelofibrosis, fibrotic stage, 49 with prefibrotic myelofibrosis, 59 with essential thrombocythemia or polycythemia vera, and 43 normal controls. Levels of ECFC frequency for patient's characteristics were estimated by using logistic regression in univariate and multivariate setting. The sensitivity, specificity, likelihood ratios, and positive predictive value of increased ECFC frequency were calculated for the significantly associated characteristics. Increased frequency of ECFCs resulted independently associated with history of splanchnic vein thrombosis (adjusted odds ratio = 6.61, 95% CI = 2.54-17.16, and a summary measure of non-active disease, i.e. hemoglobin of 13.8 g/dL or lower, white blood cells count of 7.8×10(9/L or lower, and platelet count of 400×10(9/L or lower (adjusted odds ratio = 4.43, 95% CI = 1.45-13.49 Thirteen patients with splanchnic vein thrombosis non associated with myeloproliferative neoplasms were recruited as controls. We excluded a causal role of splanchnic vein thrombosis in ECFCs increase, since no control had elevated ECFCs. We concluded that increased frequency of ECFCs represents the biological hallmark of a non-active myeloproliferative neoplasm with high risk of splanchnic vein thrombosis. The recognition of this disease category copes with the phenotypic mimicry of myeloproliferative neoplasms. Due to inherent performance limitations of ECFCs assay, there is an urgent need to arrive to an acceptable standardization of ECFC assessment.

  8. Hybrid clone cells derived from human breast epithelial cells and human breast cancer cells exhibit properties of cancer stem/initiating cells.

    Science.gov (United States)

    Gauck, Daria; Keil, Silvia; Niggemann, Bernd; Zänker, Kurt S; Dittmar, Thomas

    2017-08-02

    The biological phenomenon of cell fusion has been associated with cancer progression since it was determined that normal cell × tumor cell fusion-derived hybrid cells could exhibit novel properties, such as enhanced metastatogenic capacity or increased drug resistance, and even as a mechanism that could give rise to cancer stem/initiating cells (CS/ICs). CS/ICs have been proposed as cancer cells that exhibit stem cell properties, including the ability to (re)initiate tumor growth. Five M13HS hybrid clone cells, which originated from spontaneous cell fusion events between M13SV1-EGFP-Neo human breast epithelial cells and HS578T-Hyg human breast cancer cells, and their parental cells were analyzed for expression of stemness and EMT-related marker proteins by Western blot analysis and confocal laser scanning microscopy. The frequency of ALDH1-positive cells was determined by flow cytometry using AldeRed fluorescent dye. Concurrently, the cells' colony forming capabilities as well as the cells' abilities to form mammospheres were investigated. The migratory activity of the cells was analyzed using a 3D collagen matrix migration assay. M13HS hybrid clone cells co-expressed SOX9, SLUG, CK8 and CK14, which were differently expressed in parental cells. A variation in the ALDH1-positive putative stem cell population was observed among the five hybrids ranging from 1.44% (M13HS-7) to 13.68% (M13HS-2). In comparison to the parental cells, all five hybrid clone cells possessed increased but also unique colony formation and mammosphere formation capabilities. M13HS-4 hybrid clone cells exhibited the highest colony formation capacity and second highest mammosphere formation capacity of all hybrids, whereby the mean diameter of the mammospheres was comparable to the parental cells. In contrast, the largest mammospheres originated from the M13HS-2 hybrid clone cells, whereas these cells' mammosphere formation capacity was comparable to the parental breast cancer cells. All M13HS

  9. Freeze-drying of mononuclear cells derived from umbilical cord blood followed by colony formation.

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    Dity Natan

    Full Text Available BACKGROUND: We recently showed that freeze-dried cells stored for 3 years at room temperature can direct embryonic development following cloning. However, viability, as evaluated by membrane integrity of the cells after freeze-drying, was very low; and it was mainly the DNA integrity that was preserved. In the present study, we improved the cells' viability and functionality after freeze-drying. METHODOLOGY/PRINCIPAL FINDINGS: We optimized the conditions of directional freezing, i.e. interface velocity and cell concentration, and we added the antioxidant EGCG to the freezing solution. The study was performed on mononuclear cells (MNCs derived from human umbilical cord blood. After freeze-drying, we tested the viability, number of CD34(+-presenting cells and ability of the rehydrated hematopoietic stem cells to differentiate into different blood cells in culture. The viability of the MNCs after freeze-drying and rehydration with pure water was 88%-91%. The total number of CD34(+-presenting cells and the number of colonies did not change significantly when evaluated before freezing, after freeze-thawing, and after freeze-drying (5.4 x 10(4+/-4.7, 3.49 x 10(4+/-6 and 6.31 x 10(4+/-12.27 cells, respectively, and 31+/-25.15, 47+/-45.8 and 23.44+/-13.3 colonies, respectively. CONCLUSIONS: This is the first report of nucleated cells which have been dried and then rehydrated with double-distilled water remaining viable, and of hematopoietic stem cells retaining their ability to differentiate into different blood cells.

  10. Effect of aspirin on tumour cell colony formation and evolution.

    Science.gov (United States)

    Wodarz, Dominik; Goel, Ajay; Boland, C Richard; Komarova, Natalia L

    2017-09-01

    Aspirin is known to reduce the risk of colorectal cancer (CRC) incidence, but the underlying mechanisms are not fully understood. In a previous study, we quantified the in vitro growth kinetics of different CRC tumour cell lines treated with varying doses of aspirin, measuring the rate of cell division and cell death. Here, we use these measured parameters to calculate the chances of successful clonal expansion and to determine the evolutionary potential of the tumour cell lines in the presence and absence of aspirin. The calculations indicate that aspirin increases the probability that a single tumour cell fails to clonally expand. Further, calculations suggest that aspirin increases the evolutionary potential of an expanding tumour cell colony. An aspirin-treated tumour cell population is predicted to result in the accumulation of more mutations (and is thus more virulent and more difficult to treat) than a cell population of the same size that grew without aspirin. This indicates a potential trade-off between delaying the onset of cancer and increasing its evolutionary potential through chemoprevention. Further work needs to investigate to what extent these findings apply to in vivo settings, and to what degree they contribute to the epidemiologically documented aspirin-mediated protection. © 2017 The Author(s).

  11. Sphere-forming cell subpopulations with cancer stem cell properties in human hepatoma cell lines

    Directory of Open Access Journals (Sweden)

    Chen Lei

    2011-06-01

    Full Text Available Abstract Background Cancer stem cells (CSCs are regarded as the cause of tumor formation and recurrence. The isolation and identification of CSCs could help to develop novel therapeutic strategies specifically targeting CSCs. Methods Human hepatoma cell lines were plated in stem cell conditioned culture system allowed for sphere forming. To evaluate the stemness characteristics of spheres, the self-renewal, proliferation, chemoresistance, tumorigenicity of the PLC/PRF/5 sphere-forming cells, and the expression levels of stem cell related proteins in the PLC/PRF/5 sphere-forming cells were assessed, comparing with the parental cells. The stem cell RT-PCR array was performed to further explore the biological properties of liver CSCs. Results The PLC/PRF/5, MHCC97H and HepG2 cells could form clonal nonadherent 3-D spheres and be serially passaged. The PLC/PRF/5 sphere-forming cells possessed a key criteria that define CSCs: persistent self-renewal, extensive proliferation, drug resistance, overexpression of liver CSCs related proteins (Oct3/4, OV6, EpCAM, CD133 and CD44. Even 500 sphere-forming cells were able to form tumors in NOD/SCID mice, and the tumor initiating capability was not decreased when spheres were passaged. Besides, downstream proteins DTX1 and Ep300 of the CSL (CBF1 in humans, Suppressor of hairless in Drosophila and LAG1 in C. elegans -independent Notch signaling pathway were highly expressed in the spheres, and a gamma-secretase inhibitor MRK003 could significantly inhibit the sphere formation ability. Conclusions Nonadherent tumor spheres from hepatoma cell lines cultured in stem cell conditioned medium possess liver CSC properties, and the CSL-independent Notch signaling pathway may play a role in liver CSCs.

  12. Post-UV colony-forming ability of normal fibroblast strains and of the xeroderma pigmentosum group G strain

    International Nuclear Information System (INIS)

    Barrett, S.F.; Tarone, R.E.; Moshell, A.N.; Ganges, M.B.; Robbins, J.H.

    1981-01-01

    In xeroderma pigmentosum, an inherited disorder of defective DNA repair, post-uv colony-forming ability of fibroblasts from patients in complementation groups A through F correlates with the patients' neurological status. The first xeroderma pigmentosum patient assigned to the recently discovered group G had the neurological abnormalities of XP. Researchers have determined the post-uv colony-forming ability of cultured fibroblasts from this patient and from 5 more control donors. Log-phase fibroblasts were irradiated with 254 nm uv light from a germicidal lamp, trypsinized, and replated at known densities. After 2 to 4 weeks' incubation the cells were fixed, stained and scored for colony formation. The strains' post-uv colony-forming ability curves were obtained by plotting the log of the percent remaining post-uv colony-forming ability as a function of the uv dose. The post-uv colony-forming ability of 2 of the 5 new normal strains was in the previously defined control donor zone, but that of the other 3 extended down to the level of the most resistant xeroderma pigmentosum strain. The post-uv colony-forming ability curve of the group G fibroblasts was not significantly different from the curves of the group D fibroblast strains from patients with clinical histories similar to that of the group G patient

  13. Colony Expansion of Socially Motile Myxococcus xanthus Cells Is Driven by Growth, Motility, and Exopolysaccharide Production.

    Directory of Open Access Journals (Sweden)

    Pintu Patra

    2016-06-01

    Full Text Available Myxococcus xanthus, a model organism for studies of multicellular behavior in bacteria, moves exclusively on solid surfaces using two distinct but coordinated motility mechanisms. One of these, social (S motility is powered by the extension and retraction of type IV pili and requires the presence of exopolysaccharides (EPS produced by neighboring cells. As a result, S motility requires close cell-to-cell proximity and isolated cells do not translocate. Previous studies measuring S motility by observing the colony expansion of cells deposited on agar have shown that the expansion rate increases with initial cell density, but the biophysical mechanisms involved remain largely unknown. To understand the dynamics of S motility-driven colony expansion, we developed a reaction-diffusion model describing the effects of cell density, EPS deposition and nutrient exposure on the expansion rate. Our results show that at steady state the population expands as a traveling wave with a speed determined by the interplay of cell motility and growth, a well-known characteristic of Fisher's equation. The model explains the density-dependence of the colony expansion by demonstrating the presence of a lag phase-a transient period of very slow expansion with a duration dependent on the initial cell density. We propose that at a low initial density, more time is required for the cells to accumulate enough EPS to activate S-motility resulting in a longer lag period. Furthermore, our model makes the novel prediction that following the lag phase the population expands at a constant rate independent of the cell density. These predictions were confirmed by S motility experiments capturing long-term expansion dynamics.

  14. Colony Expansion of Socially Motile Myxococcus xanthus Cells Is Driven by Growth, Motility, and Exopolysaccharide Production.

    Science.gov (United States)

    Patra, Pintu; Kissoon, Kimberley; Cornejo, Isabel; Kaplan, Heidi B; Igoshin, Oleg A

    2016-06-01

    Myxococcus xanthus, a model organism for studies of multicellular behavior in bacteria, moves exclusively on solid surfaces using two distinct but coordinated motility mechanisms. One of these, social (S) motility is powered by the extension and retraction of type IV pili and requires the presence of exopolysaccharides (EPS) produced by neighboring cells. As a result, S motility requires close cell-to-cell proximity and isolated cells do not translocate. Previous studies measuring S motility by observing the colony expansion of cells deposited on agar have shown that the expansion rate increases with initial cell density, but the biophysical mechanisms involved remain largely unknown. To understand the dynamics of S motility-driven colony expansion, we developed a reaction-diffusion model describing the effects of cell density, EPS deposition and nutrient exposure on the expansion rate. Our results show that at steady state the population expands as a traveling wave with a speed determined by the interplay of cell motility and growth, a well-known characteristic of Fisher's equation. The model explains the density-dependence of the colony expansion by demonstrating the presence of a lag phase-a transient period of very slow expansion with a duration dependent on the initial cell density. We propose that at a low initial density, more time is required for the cells to accumulate enough EPS to activate S-motility resulting in a longer lag period. Furthermore, our model makes the novel prediction that following the lag phase the population expands at a constant rate independent of the cell density. These predictions were confirmed by S motility experiments capturing long-term expansion dynamics.

  15. Comparison of 864 and 935 MHz microwave radiation effects on cell culture

    International Nuclear Information System (INIS)

    Pavicic, I.; Trosic, I.; Sarolic, A.

    2005-01-01

    The aim of our study was to evaluate and compare the effect of 864 and 935 MHz microwave radiation on proliferation, colony forming and viability of Chinese hamster lung cells, cell line V79. Cell cultures were exposed both to the 864 MHz microwave field in transversal electromagnetic mode cell (TEM-cell) and to the 935 MHz field in Gigahertz transversal electromagnetic mode cell (GTEM-cell) for 1, 2 and 3 hours. Philips PM 5508 generator connected with a signal amplifier generated the frequency of 864 MHz, whereas Hewlett Packard HP8657A signal generator was used to generate the frequency of 935 MHz. The average specific absorption rate (SAR) was 0.08 W/kg for 864 MHz and 0.12 W/kg for 935 MHz. To determine the cell growth, V79 cells were plated in the concentration of 1x10 4 cells per milliliter of nutrient medium. Cells were cultured in a humidified atmosphere at 37 degrees of C in 5% CO 2 . Cell proliferation was determined by cell counts for each hour of exposure during the five post-exposure days. To identify colony-forming ability, cells were cultivated in the concentration of 40 cells/mL of medium and incubated as described above. Colony-forming ability was assessed for each exposure time by colony count on post-exposure day 7. Trypan blue exclusion test was used to determine cell viability. On post-exposure day 3, the growth curve of 864 MHz irradiated cells showed a significant decrease (p less than 0.05) after 2 and 3 hours of exposure in comparison with control cells. Cells exposed to 935 MHz radiation showed a significant decrease (p less than 0.05) after 3 hours of exposure on post-exposure day 3. Both the colony-forming ability and viability of 864 MHz and 935 MHz exposed cells did not significantly differ from matched control cells. In conclusion, both applied RF/MW fields have shown similar effects on cell culture growth, colony forming and cell viability of the V79 cell line.(author)

  16. Thymidine kinase deficient human cells have increased UV sensitivity in their capacity to support herpes simplex virus but normal UV sensitivity for colony formation

    International Nuclear Information System (INIS)

    Rainbow, A.J.

    1989-01-01

    A thymidine kinase deficient (tk - ) and two thymidine kinase proficient (tk + ) human cell lines were compared for UV sensitivity using colony-forming ability as well as their capacity to support the plaque formation of herpes simplex type 1 (HSV-1).The tk - line (143 cells) was a derivative of one of the tk + lines (R970-5), whereas the other tk + line (AC4 cells) was a derivative of the 143 cells obtained by transfection with purified sheared HSV-2 DNA encoding the viral tk gene. 143, R970-5 and AC4 cells showed a similar UV sensitivity for colony-forming ability. In contrast, the capacity to support HSV-1 plaque formation immediately (within 1 h) afte UV-irradiation was reduced to a greater extent in the 143 cells compared to the R970-5 and AC4 cells. Capacity curves for plaque formation of the HSV-1: KOS wild-type (tk + ) strain were similar to those for the HSV-1: PTK3B mutant (tk - ) strain were similar to those for the HSV-1: PTK3B mutant (tk - ) strain in the 3 cell strains, indicating that the viral tk gene does not influence the ability of HSV-1 to form plaques in UV-irradiated compared to unirradiated human cells. Cellular capacity for HSV-1 plaque formation was found to recover in both tk - and tk + cells for cultures infected 24 h after UV-irradiation. These results suggest that repair of UV-damaged DNA takes place to a similar extent in both tk - and tk + human cells, but the kinetics of repair are initially slower in tk - compared to tk + human cells. (author). 33 refs.; 3 figs.; 1 tab

  17. Resistance of human and mouse myeloid leukemia cells to UV radiation

    International Nuclear Information System (INIS)

    Poljak-Blazi, M.; Osmak, M.; Hadzija, M.

    1989-01-01

    Sensitivity of mouse bone marrow and myeloid leukemia cells and sensitivity of human myeloid leukemia cells to UV light was tested. Criteria were the in vivo colony-forming ability of UV exposed cells and the inhibition of DNA synthesis during post-irradiation incubation for 24 h in vitro. Mouse bone marrow cells irradiated with a small dose of UV light (5 J/m 2 ) and injected into x-irradiated animals did not form hemopoietic colonies on recipient's spleens, and recipients died. However, mouse leukemia cells, after irradiation with higher doses of UV light, retained the ability to form colonies on the spleens, and all recipient mice died with typical symptoms of leukemia. In vitro, mouse bone marrow cells exhibited high sensitivity to UV light compared to mouse myeloid leukemia cells. Human leukemia cells were also resistant to UV light, but more sensitive than mouse leukemia cells. (author)

  18. Clonal analysis of the progeny of UV-irradiated cells of Bacillus subtilis (uvr+ and uvr)

    International Nuclear Information System (INIS)

    Lotareva, O.V.; Filippov, V.D.

    1975-01-01

    The revertants to adenine prototrophy or mutants to auxotrophy can be easily identified on synthetic media which are pathly enriched with caseine hydrolyzate and yeast extract. It is shown with the use of these media that 1.5% colonies formed by Bacillus subtilis cells of the original type (ade6 met5) have mutant clones which are initiated by spontaneous revertants to adenine prototrophy. These revertants arise in the time of division of cells in macrocolonies. After plating diluted suspension of irradiated cells those colonies which contain mutant clones formed by spontaneous revertants can be erroneously taken for mixed colonies formed by induced revertants. About 40% mutants to auxotrophy induced by high dose of UV-light in uvr + cells form pure mutant colonies. The same mutants, induced in uvr cells by a five-times as-low UV-dose, usually form mixed colonies

  19. Deep vector-based convolutional neural network approach for automatic recognition of colonies of induced pluripotent stem cells.

    Directory of Open Access Journals (Sweden)

    Muthu Subash Kavitha

    Full Text Available Pluripotent stem cells can potentially be used in clinical applications as a model for studying disease progress. This tracking of disease-causing events in cells requires constant assessment of the quality of stem cells. Existing approaches are inadequate for robust and automated differentiation of stem cell colonies. In this study, we developed a new model of vector-based convolutional neural network (V-CNN with respect to extracted features of the induced pluripotent stem cell (iPSC colony for distinguishing colony characteristics. A transfer function from the feature vectors to the virtual image was generated at the front of the CNN in order for classification of feature vectors of healthy and unhealthy colonies. The robustness of the proposed V-CNN model in distinguishing colonies was compared with that of the competitive support vector machine (SVM classifier based on morphological, textural, and combined features. Additionally, five-fold cross-validation was used to investigate the performance of the V-CNN model. The precision, recall, and F-measure values of the V-CNN model were comparatively higher than those of the SVM classifier, with a range of 87-93%, indicating fewer false positives and false negative rates. Furthermore, for determining the quality of colonies, the V-CNN model showed higher accuracy values based on morphological (95.5%, textural (91.0%, and combined (93.2% features than those estimated with the SVM classifier (86.7, 83.3, and 83.4%, respectively. Similarly, the accuracy of the feature sets using five-fold cross-validation was above 90% for the V-CNN model, whereas that yielded by the SVM model was in the range of 75-77%. We thus concluded that the proposed V-CNN model outperforms the conventional SVM classifier, which strongly suggests that it as a reliable framework for robust colony classification of iPSCs. It can also serve as a cost-effective quality recognition tool during culture and other experimental

  20. Accumulation of neutral mutations in growing cell colonies with competition.

    Science.gov (United States)

    Sorace, Ron; Komarova, Natalia L

    2012-12-07

    Neutral mutations play an important role in many biological processes including cancer initiation and progression, the generation of drug resistance in bacterial and viral diseases as well as cancers, and the development of organs in multicellular organisms. In this paper we study how neutral mutants are accumulated in nonlinearly growing colonies of cells subject to growth constraints such as crowding or lack of resources. We investigate different types of growth control which range from "division-controlled" to "death-controlled" growth (and various mixtures of both). In division-controlled growth, the burden of handling overcrowding lies with the process of cell-divisions, the divisions slow down as the carrying capacity is approached. In death-controlled growth, it is death rate that increases to slow down expansion. We show that division-controlled growth minimizes the number of accumulated mutations, and death-controlled growth corresponds to the maximum number of mutants. We check that these results hold in both deterministic and stochastic settings. We further develop a general (deterministic) theory of neutral mutations and achieve an analytical understanding of the mutant accumulation in colonies of a given size in the absence of back-mutations. The long-term dynamics of mutants in the presence of back-mutations is also addressed. In particular, with equal forward- and back-mutation rates, if division-controlled and a death-controlled types are competing for space and nutrients, cells obeying division-controlled growth will dominate the population. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Stable radioresistance in ataxia-telangiectasia cells containing DNA from normal human cells

    International Nuclear Information System (INIS)

    Kapp, L.N.; Painter, R.B.

    1989-01-01

    SV40-transformed ataxia-telangiectasia (AT) cells were transfected with a cosmid containing a normal human DNA library and selectable marker, the neo gene, which endows successfully transformed mammalian cells with resistance to the antibiotic G418. Cells from this line were irradiated with 50 Gy of X-rays and fused with non-transfected AT cells. Among the G418-resistant colonies recovered was one stably resistant to radiation. Resistance to ionizing radiation of both primary transfectant line and its fusion derivative was intermediate between that of AT cells and normal cells, as assayed by colony-forming ability and measurement of radiation-induced G 2 chromatic aberrations; both cell lines retained AT-like radioresistant DNA synthesis. Results suggest that, because radioresistance in transfected cells was not as great as in normal human cells, two hallmarks of AT, radiosensitivity and radioresistant DNA synthesis, may still be the result of a single defective AT gene. (author)

  2. Culture and Characterization of Circulating Endothelial Progenitor Cells in Patients with Renal Cell Carcinoma.

    Science.gov (United States)

    Gu, Wenyu; Sun, Wei; Guo, Changcheng; Yan, Yang; Liu, Min; Yao, Xudong; Yang, Bin; Zheng, Junhua

    2015-07-01

    Although emerging evidence demonstrates increased circulating endothelial progenitor cells in patients with solid tumors, to our knowledge it is still unknown whether such cells can be cultured from patients with highly angiogenic renal cell carcinoma. We cultured and characterized circulating endothelial progenitor cells from patients with renal cell carcinoma. The circulating endothelial progenitor cell level (percent of CD45(-)CD34(+) VEGF-R2(+) cells in total peripheral blood mononuclear cells) was quantified in 47 patients with renal cell carcinoma and 40 healthy controls. Peripheral blood mononuclear cells were then isolated from 33 patients with renal cell carcinoma and 30 healthy controls to culture and characterize circulating endothelial progenitor cells. The circulating endothelial progenitor cell level was significantly higher in patients with renal cell carcinoma than in healthy controls (0.276% vs 0.086%, p cells first emerged significantly earlier in patient than in control preparations (6.72 vs 14.67 days, p culture success rate (87.8% vs 40.0% of participants) and the number of colonies (10.06 vs 1.83) were significantly greater for patients than for controls (each p cell level correlated positively with the number of patient colonies (r = 0.762, p Cells cultured from patients and controls showed a similar growth pattern, immunophenotype, ability to uptake Ac-LDL and bind lectin, and form capillary tubes in vitro. However, significantly more VEGF-R2(+) circulating endothelial progenitor cells were found in preparations from patients with renal cell carcinoma than from healthy controls (21.1% vs 13.4%, p cell colonies, a higher cell culture success rate and more colonies were found for patients with renal cell carcinoma than for healthy controls. Results indicate the important significance of VEGF-R2(+) circulating endothelial progenitors in patients with renal cell carcinoma. Copyright © 2015 American Urological Association Education and Research

  3. Multiscale modeling of bacterial colonies: how pili mediate the dynamics of single cells and cellular aggregates

    Science.gov (United States)

    Pönisch, Wolfram; Weber, Christoph A.; Juckeland, Guido; Biais, Nicolas; Zaburdaev, Vasily

    2017-01-01

    Neisseria gonorrhoeae is the causative agent of one of the most common sexually transmitted diseases, gonorrhea. Over the past two decades there has been an alarming increase of reported gonorrhea cases where the bacteria were resistant to the most commonly used antibiotics thus prompting for alternative antimicrobial treatment strategies. The crucial step in this and many other bacterial infections is the formation of microcolonies, agglomerates consisting of up to several thousands of cells. The attachment and motility of cells on solid substrates as well as the cell-cell interactions are primarily mediated by type IV pili, long polymeric filaments protruding from the surface of cells. While the crucial role of pili in the assembly of microcolonies has been well recognized, the exact mechanisms of how they govern the formation and dynamics of microcolonies are still poorly understood. Here, we present a computational model of individual cells with explicit pili dynamics, force generation and pili-pili interactions. We employ the model to study a wide range of biological processes, such as the motility of individual cells on a surface, the heterogeneous cell motility within the large cell aggregates, and the merging dynamics and the self-assembly of microcolonies. The results of numerical simulations highlight the central role of pili generated forces in the formation of bacterial colonies and are in agreement with the available experimental observations. The model can quantify the behavior of multicellular bacterial colonies on biologically relevant temporal and spatial scales and can be easily adjusted to include the geometry and pili characteristics of various bacterial species. Ultimately, the combination of the microbiological experimental approach with the in silico model of bacterial colonies might provide new qualitative and quantitative insights on the development of bacterial infections and thus pave the way to new antimicrobial treatments.

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

    International Nuclear Information System (INIS)

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

    2009-01-01

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

  5. Early Developmental Program Shapes Colony Morphology in Bacteria

    Directory of Open Access Journals (Sweden)

    Gideon Mamou

    2016-03-01

    Full Text Available When grown on a solid surface, bacteria form highly organized colonies, yet little is known about the earliest stages of colony establishment. Following Bacillus subtilis colony development from a single progenitor cell, a sequence of highly ordered spatiotemporal events was revealed. Colony was initiated by the formation of leading-cell chains, deriving from the colony center and extending in multiple directions, typically in a “Y-shaped” structure. By eradicating particular cells during these early stages, we could influence the shape of the resulting colony and demonstrate that Y-arm extension defines colony size. A mutant in ymdB encoding a phosphodiesterase displayed unordered developmental patterns, indicating a role in guiding these initial events. Finally, we provide evidence that intercellular nanotubes contribute to proper colony formation. In summary, we reveal a “construction plan” for building a colony and provide the initial molecular basis for this process.

  6. In vitro induction of alkaline phosphatase levels predicts in vivo bone forming capacity of human bone marrow stromal cells

    Directory of Open Access Journals (Sweden)

    Henk-Jan Prins

    2014-03-01

    Full Text Available One of the applications of bone marrow stromal cells (BMSCs that are produced by ex vivo expansion is for use in in vivo bone tissue engineering. Cultured stromal cells are a mixture of cells at different stages of commitment and expansion capability, leading to a heterogeneous cell population that each time can differ in the potential to form in vivo bone. A parameter that predicts for in vivo bone forming capacity is thus far lacking. We employed single colony-derived BMSC cultures to identify such predictive parameters. Using limiting dilution, we have produced sixteen single CFU-F derived BMSC cultures from human bone marrow and found that only five of these formed bone in vivo. The single colony-derived BMSC strains were tested for proliferation, osteogenic-, adipogenic- and chondrogenic differentiation capacity and the expression of a variety of associated markers. The only robust predictors of in vivo bone forming capacity were the induction of alkaline phosphatase, (ALP mRNA levels and ALP activity during in vitro osteogenic differentiation. The predictive value of in vitro ALP induction was confirmed by analyzing “bulk-cultured” BMSCs from various bone marrow biopsies. Our findings show that in BMSCs, the additional increase in ALP levels over basal levels during in vitro osteogenic differentiation is predictive of in vivo performance.

  7. Inhibition of Blumeria graminis germination and germling development within colonies of oat mildew

    DEFF Research Database (Denmark)

    Carver, T.L.W.; Roberts, P.C.; Thomas, B.J.

    2001-01-01

    Germination by Blumeria graminis. DC Speer ff. spp. avenae, hordei and tritici, was greatly suppressed when conidia fell within colonies of ff. spp. avenae or hordei established on susceptible oat or barley, respectively. On healthy oat or barley, and when distant from powdery mildew, colonies. all...... ff. spp. formed normal appressoria. This was also true When conidia germinated within established barley mildew colonies. Within barley mildew colonies, appressoria of f. sp. hordei penetrated epidermal cells formed haustoria more frequently than appressoria distant from colonies. Similarly, ff. spp....... avenae and tritici, normally unable to infect barley. frequently penetrated epidermal cells subtending established barley mildew colonies. Thus, colony, establishment induced barley epidermal cell accessibility, even to non-pathogenic ff. spp, In contrast. when all three ff. spp. germinated within...

  8. Effects of ultrasound, cysteamine, and x-rays on V79 Chinese hamster cells

    International Nuclear Information System (INIS)

    Fu, Y.K.

    1978-01-01

    Chinese hamster V79 cells were exposed to different intensities and durations of 1 MHz ultrasound and were studied for cell lysis and colony-forming ability. The threshold for cell lysis and loss of viability (reduction in colony-forming ability) were found to be ultrasonic intensity, sonication duration, and energy dependent. Above the threshold there was an initial correlation between ultrasound intensity and biological effect: the higher the intensity, the greater the amount of cell lysis and reduction in colony-forming ability. These effects were maximal at an intensity of 10-20 W/cm 2 , and were less at 30 W/cm 2 . Cells were also exposed to ultrasound in the presence of cysteamine and results are compared with the effects of x radiation on cells exposed in the presence of cysteamine or methionine

  9. Long-Term Expansion in Platelet Lysate Increases Growth of Peripheral Blood-Derived Endothelial-Colony Forming Cells and Their Growth Factor-Induced Sprouting Capacity.

    Science.gov (United States)

    Tasev, Dimitar; van Wijhe, Michiel H; Weijers, Ester M; van Hinsbergh, Victor W M; Koolwijk, Pieter

    2015-01-01

    Efficient implementation of peripheral blood-derived endothelial-colony cells (PB-ECFCs) as a therapeutical tool requires isolation and generation of a sufficient number of cells in ex vivo conditions devoid of animal-derived products. At present, little is known how the isolation and expansion procedure in xenogeneic-free conditions affects the therapeutical capacity of PB-ECFCs. The findings presented in this study indicate that human platelet lysate (PL) as a serum substitute yields twice more colonies per mL blood compared to the conventional isolation with fetal bovine serum (FBS). Isolated ECFCs displayed a higher proliferative ability in PL supplemented medium than cells in FBS medium during 30 days expansion. The cells at 18 cumulative population doubling levels (CPDL) retained their proliferative capacity, showed higher sprouting ability in fibrin matrices upon stimulation with FGF-2 and VEGF-A than the cells at 6 CPDL, and displayed low β-galactosidase activity. The increased sprouting of PB-ECFCs at 18 CPDL was accompanied by an intrinsic activation of the uPA/uPAR fibrinolytic system. Induced deficiency of uPA (urokinase-type plasminogen activator) or uPAR (uPA receptor) by siRNA technology completely abolished the angiogenic ability of PB-ECFCs in fibrin matrices. During the serial expansion, the gene induction of the markers associated with inflammatory activation such as VCAM-1 and ICAM-1 did not occur or only to limited extent. While further propagation up to 31 CPDL proceeded at a comparable rate, a marked upregulation of inflammatory markers occurred in all donors accompanied by a further increase of uPA/uPAR gene induction. The observed induction of inflammatory genes at later stages of long-term propagation of PB-ECFCs underpins the necessity to determine the right time-point for harvesting of sufficient number of cells with preserved therapeutical potential. The presented isolation method and subsequent cell expansion in platelet lysate

  10. Long-Term Expansion in Platelet Lysate Increases Growth of Peripheral Blood-Derived Endothelial-Colony Forming Cells and Their Growth Factor-Induced Sprouting Capacity.

    Directory of Open Access Journals (Sweden)

    Dimitar Tasev

    Full Text Available Efficient implementation of peripheral blood-derived endothelial-colony cells (PB-ECFCs as a therapeutical tool requires isolation and generation of a sufficient number of cells in ex vivo conditions devoid of animal-derived products. At present, little is known how the isolation and expansion procedure in xenogeneic-free conditions affects the therapeutical capacity of PB-ECFCs.The findings presented in this study indicate that human platelet lysate (PL as a serum substitute yields twice more colonies per mL blood compared to the conventional isolation with fetal bovine serum (FBS. Isolated ECFCs displayed a higher proliferative ability in PL supplemented medium than cells in FBS medium during 30 days expansion. The cells at 18 cumulative population doubling levels (CPDL retained their proliferative capacity, showed higher sprouting ability in fibrin matrices upon stimulation with FGF-2 and VEGF-A than the cells at 6 CPDL, and displayed low β-galactosidase activity. The increased sprouting of PB-ECFCs at 18 CPDL was accompanied by an intrinsic activation of the uPA/uPAR fibrinolytic system. Induced deficiency of uPA (urokinase-type plasminogen activator or uPAR (uPA receptor by siRNA technology completely abolished the angiogenic ability of PB-ECFCs in fibrin matrices. During the serial expansion, the gene induction of the markers associated with inflammatory activation such as VCAM-1 and ICAM-1 did not occur or only to limited extent. While further propagation up to 31 CPDL proceeded at a comparable rate, a marked upregulation of inflammatory markers occurred in all donors accompanied by a further increase of uPA/uPAR gene induction. The observed induction of inflammatory genes at later stages of long-term propagation of PB-ECFCs underpins the necessity to determine the right time-point for harvesting of sufficient number of cells with preserved therapeutical potential.The presented isolation method and subsequent cell expansion in platelet

  11. Photovoltaic cell module and method of forming

    Science.gov (United States)

    Howell, Malinda; Juen, Donnie; Ketola, Barry; Tomalia, Mary Kay

    2017-12-12

    A photovoltaic cell module, a photovoltaic array including at least two modules, and a method of forming the module are provided. The module includes a first outermost layer and a photovoltaic cell disposed on the first outermost layer. The module also includes a second outermost layer disposed on the photovoltaic cell and sandwiching the photovoltaic cell between the second outermost layer and the first outermost layer. The method of forming the module includes the steps of disposing the photovoltaic cell on the first outermost layer, disposing a silicone composition on the photovoltaic cell, and compressing the first outermost layer, the photovoltaic cell, and the second layer to form the photovoltaic cell module.

  12. Increased biological activity of deglycosylated recombinant human granulocyte/macrophage colony-stimulating factor produced by yeast or animal cells

    International Nuclear Information System (INIS)

    Moonen, P.; Mermod, J.J.; Ernst, J.F.; Hirschi, M.; DeLamarter, J.F.

    1987-01-01

    Human granulocyte/macrophage colony-stimulating factor (hGM-CSF) produced by several recombinant sources including Escherichia coli, yeast, and animal cells was studied. Recombinant animal cells produced hGM-CSF in low quantities and in multiple forms of varying size. Mammalian hGM-CSF was purified 200,000-fold using immunoaffinity and lectin chromatography. Partially purified proteins produced in yeast and mammalian cells were assayed for the effects of deglycosylation. Following enzymatic deglycosylation, immunoreactivity was measured by radioimmunoassay and biological activity was measured in vitro on responsive human primary cells. Removal of N-linked oligosaccharides from both proteins increased their immunoreactivities by 4- to 8-fold. Removal of these oligosaccharides also increased their specific biological activities about 20-fold, to reach approximately the specific activity of recombinant hGM-CSF from E. coli. The E. coli produced-protein-lacking any carbohydrate- had by far the highest specific activity observed for the recombinant hGM-CSFs

  13. Diffuse colonies of human skin fibroblasts in relation to cellular senescence and proliferation.

    Science.gov (United States)

    Zorin, Vadim; Zorina, Alla; Smetanina, Nadezhda; Kopnin, Pavel; Ozerov, Ivan V; Leonov, Sergey; Isaev, Artur; Klokov, Dmitry; Osipov, Andreyan N

    2017-05-16

    Development of personalized skin treatment in medicine and skin care may benefit from simple and accurate evaluation of the fraction of senescent skin fibroblasts that lost their proliferative capacity. We examined whether enriched analysis of colonies formed by primary human skin fibroblasts, a simple and widely available cellular assay, could reveal correlations with the fraction of senescent cells in heterogenic cell population. We measured fractions of senescence associated β-galactosidase (SA-βgal) positive cells in either mass cultures or colonies of various morphological types (dense, mixed and diffuse) formed by skin fibroblasts from 10 human donors. Although the donors were chosen to be within the same age group (33-54 years), the colony forming efficiency of their fibroblasts (ECO-f) and the percentage of dense, mixed and diffuse colonies varied greatly among the donors. We showed, for the first time, that the SA-βgal positive fraction was the largest in diffuse colonies, confirming that they originated from cells with the least proliferative capacity. The percentage of diffuse colonies was also found to correlate with the SA-βgal positive cells in mass culture. Using Ki67 as a cell proliferation marker, we further demonstrated a strong inverse correlation (r=-0.85, p=0.02) between the percentage of diffuse colonies and the fraction of Ki67+ cells. Moreover, a significant inverse correlation (r=-0.94, p=0.0001) between the percentage of diffuse colonies and ECO-f was found. Our data indicate that quantification of a fraction of diffuse colonies may provide a simple and useful method to evaluate the extent of cellular senescence in human skin fibroblasts.

  14. Effect of fluid motion on colony formation in Microcystis aeruginosa

    Directory of Open Access Journals (Sweden)

    Lin Li

    2013-01-01

    Full Text Available Microcystis aeruginosa, generally occurring in large colonies under natural conditions, mainly exists as single cells in laboratory cultures. The mechanisms involved in colony formation in Microcystis aeruginosa and their roles in algal blooms remain unknown. In this study, based on previous research findings that fluid motion may stimulate the colony formation in green algae, culture experiments were conducted under axenic conditions in a circular water chamber where the flow rate, temperature, light, and nutrients were controlled. The number of cells of Microcystis aeruginosa, the number of cells per colony, and the colonial characteristics in various growth phases were observed and measured. The results indicated that the colony formation in Microcystis aeruginosa, which was not observed under stagnant conditions, was evident when there was fluid motion, with the number of cells per largest colony reaching 120 and the proportion of the number of cells in colonial form to the total number of cells and the mean number of cells per colony reaching their peak values at a flow rate of 35 cm/s. Based on the analysis of colony formation process, fluid motion stimulates the colony formation in Microcystis aeruginosa in the lag growth phase, while flushes and disaggregates the colonies in the exponential growth phase. The stimulation effect in the lag growth phase may be attributable to the involvement of fluid motion in a series of physiological processes, including the uptake of trace elements and the synthesis and secretion of polysaccharides. In addition, the experimental groups exhibiting typical colonial characteristics in the lag growth phase were found to have higher cell biomass in the later phase.

  15. The influence of interleukin-2, feeder cells, and timing of irradiation on the radiosensitivity of human T lymphocytes assessed by the colony-forming assay

    International Nuclear Information System (INIS)

    Gerber, M.; Guichard, M.; Pioch, Y.; Dubois, J.B.

    1989-01-01

    The radiosensitivity of human lymphocytes was investigated by the method of colony formation in the absence of interleukin-2 (IL2) and feeder cells, both of which enhance growth of T-cell colonies. The shape of the survival curve and the radiosensitivity was shown to depend upon the ability of lymphocytes to produce IL2: the survival curve for lymphocytes that were the most competent producers of IL2 is the closest to linearity; the lymphocytes that were poor producers show biphasic survival curves. The radiosensitivity of the lymphocytes from the first group is less than that of the latter, when the comparison is based on the first part of the biphasic survival curve. This is more easily seen when cultures are irradiated 24 h after stimulation by phytohemagglutinin (the time of the peak IL2 production) than when cultures are irradiated 2 h before stimulation. This study demonstrates that growth conditions influence the response of lymphocytes to irradiation and that optimal growth conditions result in a linear survival curve

  16. Potential in a single cancer cell to produce heterogeneous morphology, radiosensitivity and gene expression

    International Nuclear Information System (INIS)

    Ban, Sadayuki; Ishikawa, Ken-ichi; Kawai, Seiko; Koyama-Saegusa, Kumiko; Ishikawa, Atsuko; Imai, Takashi; Shimada, Yutaka; Inazawa, Johji

    2005-01-01

    Morphologically heterogeneous colonies were formed from a cultured cell line (KYSE70) established from one human esophageal carcinoma tissue. Two subclones were separated from a single clone (clone 13) of KYSE70 cells. One subclone (clone 13-3G) formed mainly mounding colonies and the other (clone 13-6G) formed flat, diffusive colonies. X-irradiation stimulated the cells to dedifferentiate from the mounding state to the flat, diffusive state. Clone 13-6G cells were more radiosensitive than the other 3 cell lines. Clustering analysis for gene expression level by oligonucleotide microarray demonstrated that in the radiosensitive clone 13-6G cells, expression of genes involved in cell adhesion was upregulated, but genes involved in the response to DNA damage stimulus were downregulated. The data demonstrated that a single cancer cell had the potential to produce progeny heterogeneous in terms of morphology, radiation sensitivity and gene expression, and irradiation enhanced the dedifferentiation of cancer cells. (author)

  17. ROCK inhibitor Y-27632 enhances the survivability of dissociated buffalo (Bubalus bubalis) embryonic stem cell-like cells.

    Science.gov (United States)

    Sharma, Ruchi; George, Aman; Chauhan, Manmohan S; Singla, Suresh; Manik, Radhey S; Palta, Prabhat

    2013-01-01

    This study investigated the effects of supplementation of culture medium with 10 μM Y-27632, a specific inhibitor of Rho kinase activity, for 6 days on self-renewal of buffalo embryonic stem (ES) cell-like cells at Passage 50-80. Y-27632 increased mean colony area (P<0.05) although it did not improve their survival. It decreased OCT4 expression (P<0.05), increased NANOG expression (P<0.05), but had no effect on SOX2 expression. It also increased expression of anti-apoptotic gene BCL-2 (P<0.05) and decreased that of pro-apoptotic genes BAX and BID (P<0.05). It increased plating efficiency of single-cell suspensions of ES cells (P<0.05). Following vitrification, the presence of Y-27632 in the vitrification solution or thawing medium or both did not improve ES cell colony survival. However, following seeding of clumps of ES cells transfected with pAcGFP1N1 carrying green fluorescent protein (GFP), Y-27632 increased colony formation rate (P<0.01). ES cell colonies that formed in all Y-27632-supplemented groups were confirmed for expression of pluripotency markers alkaline phosphatase, SSEA-4 and TRA-1-60, and for their ability to generate embryoid bodies containing cells that expressed markers of ectoderm, mesoderm and endoderm. In conclusion, Y-27632 improves survival of buffalo ES cells under unfavourable conditions such as enzymatic dissociation to single cells or antibiotic-assisted selection after transfection, without compromising their pluripotency.

  18. Extrapulmonary colony formation after intravenous injection of tumour cells into heparin treated animals

    NARCIS (Netherlands)

    Maat, B.

    1978-01-01

    Recent data on extrapulmonary colony formation after heparin administration are inconclusive. A systemic study of this topic was undertaken with 4 experimental tumour systems and 2 distinct periods of reduced clotting capacity in rats and mice. I.v. injection of various numbers of tumour cells into

  19. Effect of poly-A:U, dextran sulfate and yeast RNA on the bone marrow colony-forming ability in irradiated mice

    International Nuclear Information System (INIS)

    Chernyavskij, V.I.; Lysenko, A.I.; Kulakova, G.S.

    1977-01-01

    It has been shown, that poly-A:U, dextran sulfate and yeast RNA increased a number of endogenic colonies (COE) in the mouse spleen sublethally irradiated, as a result of, apparently, their mitogenic effect on proliferous COE. The preparations did not affect the number of exogenic colonies when introducting them together with transfer of syngenic cells of bone marrow, taken from the intact donors. Dextran sulfate increased 2.7 times the number of the endogenic colonies in the spleens of nonuniformly irradiated mice mainly due to the COE migration from protected bone marrow areas. The complex of poly-A:U and yest RNA in such experiment type were ineffective. One of the most important factors in the mechanism of the dextran sulfate adjuvant activity possibly is its ability to increase migration potencies of the stem blood-forming cells

  20. Convergence of bone morphogenetic protein and laminin-1 signaling pathways promotes proliferation and colony formation by fetal mouse pancreatic cells

    International Nuclear Information System (INIS)

    Jiang Fangxu; Harrison, Leonard C.

    2005-01-01

    We previously reported that bone morphogenetic proteins (BMPs), members of the transforming growth factor superfamily, together with the basement membrane glycoprotein laminin-1 (Ln-1), promote proliferation of fetal pancreatic cells and formation of colonies containing peripheral insulin-positive cells. Here, we further investigate the cross-talk between BMP and Ln-1 signals. By RT-PCR, receptors for BMP (BMPR) (excepting BMPR-1B) and Ln-1 were expressed in the fetal pancreas between E13.5 and E17.5. Specific blocking antibodies to BMP-4 and -6 and selective BMP antagonists partially inhibited colony formation by fetal pancreas cells. Colony formation induced by BMP-6 and Ln-1 was completely abolished in a dose-dependent manner by blocking Ln-1 binding to its α 6 integrin and α-dystroglycan receptors or by blocking the Ln-1 signaling molecules, phosphatidyl-inositol-3-kinase (P13K) and MAP kinase kinase-1. These results demonstrate a convergence of BMP and Ln-1 signaling through P13K and MAP kinase pathways to induce proliferation and colony formation in E15.5 fetal mouse pancreatic cells

  1. Characterization and molecular features of the cell surface receptor for human granulocyte-macrophage colony-stimulating factor

    International Nuclear Information System (INIS)

    Chiba, S.; Tojo, A.; Kitamura, T.; Urabe, A.; Miyazono, K.; Takaku, F.

    1990-01-01

    The receptors for human granulocyte-macrophage colony-stimulating factor (GM-CSF) on the surfaces of normal and leukemic myeloid cells were characterized using 125I-labeled bacterially synthesized GM-CSF. The binding was rapid, specific, time dependent, and saturable. Scatchard analysis of the 125I-GM-CSF binding to peripheral blood neutrophils indicated the presence of a single class of binding site (Kd = 99 +/- 21 pM; 2,304 +/- 953 sites/cell). However, for peripheral blood monocytes and two GM-CSF-responsive myeloid cell lines (U-937 and TF-1), the Scatchard plots were biphasic curvilinear, which were best fit by curves derived from two binding site model: one with high affinity (Kd1 = 10-40 pM) and the other with low affinity (Kd2 = 0.9-2.0 nM). For U-937 cells, the number of high-affinity receptors was 1,058 +/- 402 sites/cell and that of low-affinity receptors was estimated to be 10,834 +/- 2,396 sites/cell. Cross-linking studies yielded three major bands with molecular masses of 150 kDa, 115 kDa, and 95 kDa, which were displaced by an excess amount of unlabeled GM-CSF, suggesting 135-kDa, 100-kDa, and 80-kDa species for the individual components of the human GM-CSF receptor. These bands comigrated for different cell types including peripheral blood neutrophils, U-937 cells and TF-1 cells. In experiments using U-937 cells, only the latter two bands appeared to be labeled in a dose-dependent manner in a low-affinity state. These results suggest that the human GM-CSF receptor possibly forms a multichain complex

  2. Studies of hematopoietic stem cells spared by 5-fluorouracil

    International Nuclear Information System (INIS)

    Van Zant, G.

    1984-01-01

    Mouse marrow cells were exposed to 5-fluorouracil (FU) either in vivo or in vitro and the effects on the hematopoietic stem cell compartment were studied. The drug was highly toxic to bone marrow cells including the spleen colony-forming unit (CFU-S) population. The small population of stem cells surviving FU, however, caused a different pattern of spleen colony growth when injected into lethally irradiated mice. Whereas numbers of spleen colonies caused by normal marrow cells remained constant during an 8-14 d period after transplantation, spleen colonies derived from FU-treated marrow cells increased by as much as 100-fold during this time. This effect on stem cells was dose dependent both in vitro and in vivo. When FU was given in vivo, the day 14/day 8 ratio of colonies was greatest 1 d after injection and, over the next 7 d, returned to a near-normal value, that is, unity. A number of studies have shown that the stem cell compartment is heterogeneous with respect to self-replicative capacity and developmental potential. An age structure for the stem cell compartment has been proposed wherein cells with a short mitotic history are more likely to self-replicate than they are to differentiate; hence they are more primitive. I propose that the delayed spleen colony appearance in normal hosts is the result of developmental maturation of the primitive stem cell compartment that survives FU and is responsible for spleen colonies arising around day 14. This maturation, at least initially, occurs in the marrow and leads to the replenishment of the more differentiated CFU-S subsets ablated by FU, which are normally responsible for spleen colonies appearing earlier after transplantation

  3. Blood-Forming Stem Cell Transplants

    Science.gov (United States)

    ... to Ask about Your Treatment Research Blood-Forming Stem Cell Transplants On This Page What are bone marrow ... Considering becoming a bone marrow or a blood stem cell donor? View this video on YouTube. Follow a ...

  4. Colony stimulating factors and their clinical implication

    International Nuclear Information System (INIS)

    Asano, Shigetaka

    1989-01-01

    Granulocytes and macrophage are dependent for their production and/or functional activation in vitro on the presence of a family of glycoproteins. They are generally called colony-stimulating factors (CSFs) because of their capacity to stimulate colony formation in semi-solid cultures, and are currently classified into four distinct subtypes, that is, Multi-CSF, GM-CSF, G-CSF and M-CSF, according to the cell type of colonies formed under their stimulation or their target cell specificity. All of the murine and human CSF subtypes and the genes for them have become available in a purified form and in a large scale, and now allow us to investigate their interactions, the mechanisms for their actions, the cell-cell interactions leading to their production and secretion, and their actions in vivo. Furthermore, the preclinical and/or clinical studies which were carried out using the purified CSFs strongly indicate that human CSFs will be effective strategies for preventing and treating opportunistic bacterial and fungal infection as a major cause of death in granulocytopenic patients. (author)

  5. Optimization of culture conditions to support long-term self-renewal of buffalo (Bubalus bubalis) embryonic stem cell-like cells.

    Science.gov (United States)

    Sharma, Ruchi; George, Aman; Kamble, Nitin Manchindra; Singh, Karn Pratap; Chauhan, Manmohan Singh; Singla, Suresh Kumar; Manik, Radhey Sham; Palta, Prabhat

    2011-12-01

    A culture system capable of sustaining self-renewal of buffalo embryonic stem (ES) cell-like cells in an undifferentiated state over a long period of time was developed. Inner cell masses were seeded on KO-DMEM+15% KO-serum replacer on buffalo fetal fibroblast feeder layer. Supplementation of culture medium with 5 ng/mL FGF-2 and 1000 IU/mL mLIF gave the highest (p<0.05) rate of primary colony formation. The ES cell-like cells' colony survival rate and increase in colony size were highest (p<0.05) following supplementation with FGF-2 and LIF compared to other groups examined. FGF-2 supplementation affected the quantitative expression of NANOG, SOX-2, ACTIVIN A, BMP 4, and TGFβ1, but not OCT4 and GREMLIN. Supplementation with SU5402, an FGFR inhibitor (≥20 μM) increased (p<0.05) the percentage of colonies that differentiated. FGFR1-3 and ERK1, K-RAS, E-RAS, and SHP-2, key signaling intermediates of FGF signaling, were detected in ES cell-like cells. Under culture conditions described, three ES cell lines were derived that, to date, have been maintained for 135, 95, and 85 passages for over 27, 19, and 17 months, respectively, whereas under other conditions examined, ES cell-like cells did not survive beyond passage 10. The ES cell-like cells were regularly monitored for expression of pluripotency markers and their potency to form embryoid bodies.

  6. Inhibitory effects of different forms of tocopherols, tocopherol phosphates, and tocopherol quinones on growth of colon cancer cells.

    Science.gov (United States)

    Dolfi, Sonia C; Yang, Zhihong; Lee, Mao-Jung; Guan, Fei; Hong, Jungil; Yang, Chung S

    2013-09-11

    Tocopherols are the major source of dietary vitamin E. In this study, the growth inhibitory effects of different forms of tocopherols (T), tocopheryl phosphates (TP), and tocopherol quinones (TQ) on human colon cancer HCT116 and HT29 cells were investigated. δ-T was more active than γ-T in inhibiting colon cancer cell growth, decreasing cancer cell colony formation, and inducing apoptosis; however, α-T was rather ineffective. Similarly, the rate of cellular uptake also followed the ranking order δ-T > γ-T ≫ α-T. TP and TQ generally had higher inhibitory activities than their parent compounds. Interestingly, the γ forms of TP and TQ were more active than the δ forms in inhibiting cancer cell growth, whereas the α forms were the least effective. The potencies of γ-TQ and δ-TQ (showing IC50 values of ∼0.8 and ∼2 μM on HCT116 cells after a 72 h incubation, respectively) were greater than 100-fold and greater than 20-fold higher, respectively, than those of their parent tocopherols. Induction of cancer cell apoptosis by δ-T, γ-TP, and γ-TQ was characterized by the cleavage of caspase 3 and PARP1 and DNA fragmentation. These studies demonstrated the higher growth inhibitory activity of δ-T than γ-T, the even higher activities of the γ forms of TP and TQ, and the ineffectiveness of the α forms of tocopherol and their metabolites against colon cancer cells.

  7. Effect of Co-Culturing of Mice Liver Cells and Embryonic Carcinomatous Stem Cells on the Rate of Differentiation to Hematopoietic Cells

    Directory of Open Access Journals (Sweden)

    AA Pourfatollah

    2005-10-01

    Full Text Available Introduction: Considering the importance of co-culture in differentiation of embryonic stem cells, the aim of this study was evaluation of the effect of co-culturing fetal liver stroma cells with P19 cells on the line of differentiation. Materials and Methods: For this purpose, P19 cells were cultured directly in semisolid medium. These cells proliferated and primarily differentiated to colonies know as embryoid bodies (EBs after 8-12 days. The Ebs cells were trypsinized and dissociated to single or double cells. Then these cells were co-cultured on the mouse fetal liver feeder layer in the absence of exogenous factors. After 14-18 days, the colonies were studied morphologically by benzidine and giemsa staining and also counted under invert microscope. Results: The percentages of benzidine positive (or erythroid and negative colonies were 94% and 6% respectively and also the cells of colonies were studied by Giemsa staining. Results showed that they were myeloid or lymphoid type cells. Thus, the results show that in the presence of mouse fetal liver feeder layer, the number of erythroid colonies was increased. Conclusions: Therefore, this technique may be effective for differentiation of stem cells from different sources into hematopoietic cells and can be used in future for human cell therapy.

  8. Swarming and complex pattern formation in Paenibacillus vortex studied by imaging and tracking cells

    Directory of Open Access Journals (Sweden)

    Jacob Eshel

    2008-02-01

    Full Text Available Abstract Background Swarming motility allows microorganisms to move rapidly over surfaces. The Gram-positive bacterium Paenibacillus vortex exhibits advanced cooperative motility on agar plates resulting in intricate colonial patterns with geometries that are highly sensitive to the environment. The cellular mechanisms that underpin the complex multicellular organization of such a simple organism are not well understood. Results Swarming by P. vortex was studied by real-time light microscopy, by in situ scanning electron microscopy and by tracking the spread of antibiotic-resistant cells within antibiotic-sensitive colonies. When swarming, P. vortex was found to be peritrichously flagellated. Swarming by the curved cells of P. vortex occurred on an extremely wide range of media and agar concentrations (0.3 to 2.2% w/v. At high agar concentrations (> 1% w/v rotating colonies formed that could be detached from the main mass of cells by withdrawal of cells into the latter. On lower percentage agars, cells moved in an extended network composed of interconnected "snakes" with short-term collision avoidance and sensitivity to extracts from swarming cells. P. vortex formed single Petri dish-wide "supercolonies" with a colony-wide exchange of motile cells. Swarming cells were coupled by rapidly forming, reversible and non-rigid connections to form a loose raft, apparently connected via flagella. Inhibitors of swarming (p-Nitrophenylglycerol and Congo Red were identified. Mitomycin C was used to trigger filamentation without inhibiting growth or swarming; this facilitated dissection of the detail of swarming. Mitomycin C treatment resulted in malcoordinated swarming and abortive side branch formation and a strong tendency by a subpopulation of the cells to form minimal rotating aggregates of only a few cells. Conclusion P. vortex creates complex macroscopic colonies within which there is considerable reflux and movement and interaction of cells. Cell

  9. Radiation-induced DNA damage in canine hemopoietic cells and stromal cells as measured by the comet assay

    International Nuclear Information System (INIS)

    Kreja, L.; Selig, C.; Plappert, U.; Nothdurft, W.

    1996-01-01

    Stromal cell progenitors (fibroblastoid colony-forming unit; CFU-Fs) are representative of the progenitor cell population of the hemopoietic microenvironment in bone marrow (BM). Previous studies of the radiation dose-effect relationships for colony formation have shown that canine CFU-Fs are relatively radioresistant as characterized by a D 0 value of about 2.4 Gy. In contrast, hemopoietic progenitors are particularly radiosensitive (D 0 values = 0.12-0.60 Gy). In the present study, the alkaline single-cell gel electrophoresis technique for the in situ quantitation of DNA strand breaks and alkalilabile site was employed. Canine buffy coat cells from BM aspirates and cells harvested from CFU-F colonies or from mixed populations of adherent BM stromal cell (SC) layers were exposed to increasing doses of X-rays, embedded in agarose gel on slides, lysed with detergents, and placed in an electric field. DNA migrating from single cells in the gel was made visible as open-quotes cometsclose quotes by ethidium bromide staining. Immediate DNA damage was much less in cultured stromal cells than in hemopoietic cells in BM aspirates. These results suggest that the observed differences in clonogenic survival could be partly due to differences in the type of the initial DNA damage between stromal cells and hemopoietic cells. 37 refs., 2 figs., 1 tab

  10. Mobilization of hematopoietic stem cells with highest self-renewal by G-CSF precedes clonogenic cell mobilization peak.

    Science.gov (United States)

    Winkler, Ingrid G; Wiercinska, Eliza; Barbier, Valerie; Nowlan, Bianca; Bonig, Halvard; Levesque, Jean-Pierre

    2016-04-01

    Harvest of granulocyte colony-stimulating factor (G-CSF)-mobilized hematopoietic stem cells (HSCs) begins at day 5 of G-CSF administration, when most donors have achieved maximal mobilization. This is based on surrogate markers for HSC mobilization, such as CD34(+) cells and colony-forming activity in blood. However, CD34(+) cells or colony-forming units in culture (CFU-C) are heterogeneous cell populations with hugely divergent long-term repopulation potential on transplantation. HSC behavior is influenced by the vascular bed in the vicinity of which they reside. We hypothesized that G-CSF may mobilize sequentially cells proximal and more distal to bone marrow venous sinuses where HSCs enter the blood. We addressed this question with functional serial transplantation assays using blood and bone marrow after specific time points of G-CSF treatment in mice. We found that in mice, blood collected after only 48 hours of G-CSF administration was as enriched in serially reconstituting HSCs as blood collected at 5 days of G-CSF treatment. Similarly, mobilized Lin(-)CD34(+) cells were relatively enriched in more primitive Lin(-)CD34(+)CD38(-) cells at day 2 of G-CSF treatment compared with later points in half of human donors tested (n = 6). This suggests that in both humans and mice, hematopoietic progenitor and stem cells do not mobilize uniformly according to their maturation stage, with most potent HSCs mobilizing as early as day 2 of G-CSF. Copyright © 2016 ISEH - International Society for Experimental Hematology. Published by Elsevier Inc. All rights reserved.

  11. Loss of the ability to generate large burst-forming unit-like megakaryocytic colonies from thawed cord blood in semisolid cultures after short term suspension culture.

    Science.gov (United States)

    Eskola, M; Bäckman, S; Möttönen, S; Kekomäki, R

    2015-04-01

    Total colony-forming cells from thawed cord blood units (CBUs) include megakaryocytic colony-forming units (CFU-Mks), which survive the freezing process. The aim of this study was to evaluate whether different megakaryocytic progenitors from unseparated CBUs survive the freezing process and a short-term liquid culture. Thawed samples of CBUs were cultured in liquid medium. During the cultures, serial samples were drawn to assess the growth of different megakaryocytic progenitors in a semisolid collagen medium with identical cytokines as in the liquid medium. Megakaryocytic cells were detected using immunohistochemistry and flow cytometry. In suspension culture, the megakaryocytic progenitors almost completely lost the ability to generate large (burst-forming unit-like, BFU-like) megakaryocytic colonies in semisolid cultures (large colonies, median count per chamber d0: 7.25 vs. d7: 1.5; P culture in suspension resulted in the decline of small colonies as well (d7: 16.0 vs. d14: 5.75; P = 0.0088). Total CFU-Mk count declined from 23.3 (range 12.5-34.0) at d0 to 7.25 (range 1.0-13.5) at d14 (P culture after a short suspension culture. Small CFU-Mks were observed throughout the cultures. It may be that the BFU-Mk colonies matured and acquired CFU-Mk behaviour. © 2014 International Society of Blood Transfusion.

  12. An Aqueous Extract of Marine Microalgae Exhibits Antimetastatic Activity through Preferential Killing of Suspended Cancer Cells and Anticolony Forming Activity

    Science.gov (United States)

    Somasekharan, Syam Prakash; El-Naggar, Amal; Sorensen, Poul H.

    2016-01-01

    Research on marine natural products as potential anticancer agents is still limited. In the present study, an aqueous extract of a Canadian marine microalgal preparation was assessed for anticancer activities using various assays and cell lines of human cancers, including lung, prostate, stomach, breast, and pancreatic cancers, as well as an osteosarcoma. In vitro, the microalgal extract exhibited marked anticolony forming activity. In addition, it was more toxic, as indicated by increased apoptosis, to nonadherent cells (grown in suspension) than to adherent cells. In vivo, an antimetastatic effect of the extract was observed in NOD-SCID mice carrying subrenal capsule xenografts of PC3 prostate cancer cells. The results of the present study suggest that the antimetastatic effect of the aqueous microalgal extract is based on inhibition of colony forming ability of cancer cells and the preferential killing of suspended cancer cells. Further research aimed at identification of the molecular basis of the anticancer activities of the microalgal extract appears to be warranted. PMID:27656243

  13. An Aqueous Extract of Marine Microalgae Exhibits Antimetastatic Activity through Preferential Killing of Suspended Cancer Cells and Anticolony Forming Activity

    Directory of Open Access Journals (Sweden)

    Syam Prakash Somasekharan

    2016-01-01

    Full Text Available Research on marine natural products as potential anticancer agents is still limited. In the present study, an aqueous extract of a Canadian marine microalgal preparation was assessed for anticancer activities using various assays and cell lines of human cancers, including lung, prostate, stomach, breast, and pancreatic cancers, as well as an osteosarcoma. In vitro, the microalgal extract exhibited marked anticolony forming activity. In addition, it was more toxic, as indicated by increased apoptosis, to nonadherent cells (grown in suspension than to adherent cells. In vivo, an antimetastatic effect of the extract was observed in NOD-SCID mice carrying subrenal capsule xenografts of PC3 prostate cancer cells. The results of the present study suggest that the antimetastatic effect of the aqueous microalgal extract is based on inhibition of colony forming ability of cancer cells and the preferential killing of suspended cancer cells. Further research aimed at identification of the molecular basis of the anticancer activities of the microalgal extract appears to be warranted.

  14. In vivo stem cell function of interleukin-3-induced blast cells

    International Nuclear Information System (INIS)

    Tsunoda, J.; Okada, S.; Suda, J.; Nagayoshi, K.; Nakauchi, H.; Hatake, K.; Miura, Y.; Suda, T.

    1991-01-01

    The treatment of mice with high doses of 5-fluorouracil (5-FU) results in an enrichment of primitive hematopoietic progenitors. Using this procedure, the authors obtained a new class of murine hematopoietic colonies that had very high secondary plating efficiencies in vitro and could differentiate into not only myeloid cells but also into lymphoid lineage cells. The phenotypes of interleukin-3 (IL-3) induced blast colony cells were Thy-1-positive and lineage-marker-negative. They examined whether these blast colony cells contained primitive hematopoietic stem cells in vivo and could reconstitute hematopoietic tissues in lethally irradiated mice. Blast colony cells could generate macroscopic visible spleen colonies on days 8 and 12, and 5 x 10(3) blast cells were sufficient to protect them from lethally irradiation. It was shown that 6 or 8 weeks after transplantation of 5 x 10(3) blast cells, donor male cells were detected in the spleen and thymus of the female recipients but not in the bone marrow by Southern blot analysis using Y-encoded DNA probe. After 10 weeks, bone marrow cells were partially repopulated from donor cells. In a congenic mouse system, donor-derived cells (Ly5.2) were detected in the thymus and spleen 6 weeks after transplantation. Fluorescence-activated cell sorter analyses showed that B cells and macrophages developed from donor cells in the spleen. In the thymus, donor-derived cells were found in CD4, CD8 double-positive, single-positive, and double-negative populations. Reconstitution of bone marrow was delayed and myeloid and lymphoid cells were detected 10 weeks after transplantation. These results indicate that IL-3-induced blast cells contain the primitive hematopoietic stem cells capable of reconstituting hematopoietic organs in lethally irradiated mice

  15. Spatio-temporal morphology changes in and quenching effects on the 2D spreading dynamics of cell colonies in both plain and methylcellulose-containing culture media.

    Science.gov (United States)

    Muzzio, N E; Pasquale, M A; Huergo, M A C; Bolzán, A E; González, P H; Arvia, A J

    2016-06-01

    To deal with complex systems, microscopic and global approaches become of particular interest. Our previous results from the dynamics of large cell colonies indicated that their 2D front roughness dynamics is compatible with the standard Kardar-Parisi-Zhang (KPZ) or the quenched KPZ equations either in plain or methylcellulose (MC)-containing gel culture media, respectively. In both cases, the influence of a non-uniform distribution of the colony constituents was significant. These results encouraged us to investigate the overall dynamics of those systems considering the morphology and size, the duplication rate, and the motility of single cells. For this purpose, colonies with different cell populations (N) exhibiting quasi-circular and quasi-linear growth fronts in plain and MC-containing culture media are investigated. For small N, the average radial front velocity and its change with time depend on MC concentration. MC in the medium interferes with cell mitosis, contributes to the local enlargement of cells, and increases the distribution of spatio-temporal cell density heterogeneities. Colony spreading in MC-containing media proceeds under two main quenching effects, I and II; the former mainly depending on the culture medium composition and structure and the latter caused by the distribution of enlarged local cell domains. For large N, colony spreading occurs at constant velocity. The characteristics of cell motility, assessed by measuring their trajectories and the corresponding velocity field, reflect the effect of enlarged, slow-moving cells and the structure of the medium. Local average cell size distribution and individual cell motility data from plain and MC-containing media are qualitatively consistent with the predictions of both the extended cellular Potts models and the observed transition of the front roughness dynamics from a standard KPZ to a quenched KPZ. In this case, quenching effects I and II cooperate and give rise to the quenched

  16. Cell envelope stress response in cell wall-deficient L-forms of Bacillus subtilis.

    Science.gov (United States)

    Wolf, Diana; Domínguez-Cuevas, Patricia; Daniel, Richard A; Mascher, Thorsten

    2012-11-01

    L-forms are cell wall-deficient bacteria that can grow and proliferate in osmotically stabilizing media. Recently, a strain of the Gram-positive model bacterium Bacillus subtilis was constructed that allowed controlled switching between rod-shaped wild-type cells and corresponding L-forms. Both states can be stably maintained under suitable culture conditions. Because of the absence of a cell wall, L-forms are known to be insensitive to β-lactam antibiotics, but reports on the susceptibility of L-forms to other antibiotics that interfere with membrane-anchored steps of cell wall biosynthesis are sparse, conflicting, and strongly influenced by strain background and method of L-form generation. Here we investigated the response of B. subtilis to the presence of cell envelope antibiotics, with regard to both antibiotic resistance and the induction of the known LiaRS- and BceRS-dependent cell envelope stress biosensors. Our results show that B. subtilis L-forms are resistant to antibiotics that interfere with the bactoprenol cycle, such as bacitracin, vancomycin, and mersacidin, but are hypersensitive to nisin and daptomycin, which both affect membrane integrity. Moreover, we established a lacZ-based reporter gene assay for L-forms and provide evidence that LiaRS senses its inducers indirectly (damage sensing), while the Bce module detects its inducers directly (drug sensing).

  17. Cell growth, intracellular calcium concentration and metabolic cooperation measured in cells exposed to 50 Hz electromagnetic fields

    International Nuclear Information System (INIS)

    Skauli, K.S.

    1996-08-01

    Colony-forming efficiency, DNA/protein and DNA/cell were measured in cells exposed to magnetic fields of 0.2 and 1 mT at a frequency of 50 Hz. Intracellular calcium concentrations were measured in cells exposed to 0.3 and 1 mT at 50 Hz. Metabolic cooperation was measured in cells exposed to 1 mT at 50 Hz. No significant effects of the fields were observed. 20 refs., 10 figs

  18. Heterogeneity of functional properties of Clone 66 murine breast cancer cells expressing various stem cell phenotypes.

    Science.gov (United States)

    Mukhopadhyay, Partha; Farrell, Tracy; Sharma, Gayatri; McGuire, Timothy R; O'Kane, Barbara; Sharp, J Graham

    2013-01-01

    Breast cancer grows, metastasizes and relapses from rare, therapy resistant cells with a stem cell phenotype (cancer stem cells/CSCs). However, there is a lack of studies comparing the functions of CSCs isolated using different phenotypes in order to determine if CSCs are homogeneous or heterogeneous. Cells with various stem cell phenotypes were isolated by sorting from Clone 66 murine breast cancer cells that grow orthotopically in immune intact syngeneic mice. These populations were compared by in vitro functional assays for proliferation, growth, sphere and colony formation; and in vivo limiting dilution analysis of tumorigenesis. The proportion of cells expressing CD44(high)CD24(low/neg), side population (SP) cells, ALDH1(+), CD49f(high), CD133(high), and CD34(high) differed, suggesting heterogeneity. Differences in frequency and size of tumor spheres from these populations were observed. Higher rates of proliferation of non-SP, ALDH1(+), CD34(low), and CD49f(high) suggested properties of transit amplifying cells. Colony formation was higher from ALDH1(-) and non-SP cells than ALDH1(+) and SP cells suggesting a progenitor phenotype. The frequency of clonal colonies that grew in agar varied and was differentially altered by the presence of Matrigel™. In vivo, fewer cells with a stem cell phenotype were needed for tumor formation than "non-stem" cells. Fewer SP cells were needed to form tumors than ALDH1(+) cells suggesting further heterogeneities of cells with stem phenotypes. Different levels of cytokines/chemokines were produced by Clone 66 with RANTES being the highest. Whether the heterogeneity reflects soluble factor production remains to be determined. These data demonstrate that Clone 66 murine breast cancer cells that express stem cell phenotypes are heterogeneous and exhibit different functional properties, and this may also be the case for human breast cancer stem cells.

  19. Proliferation, differentiation, and possible radiation-induced chromosome abnormalities in circulating hemopoietic stem cells

    International Nuclear Information System (INIS)

    Amenomori, Tatsuhiko; Honda, Takeo; Matsuo, Tatsuki; Otake, Masanori; Hazama, Ryuji; Tomonaga, Yu; Tomonaga, Masao; Ichimaru, Michito.

    1986-07-01

    The effects of atomic bomb radiation on hemopoietic stem cells were studied cytogenetically and from the aspect of differentiation and proliferation, using single colonies derived from human hemopoietic stem cells. The subjects studied were A-bomb survivors in the high dose exposure group (T65D 100 + rad) with a high incidence (10 % or more) of radiation-induced chromosome abnormalities in their peripheral lymphocytes, and their controls. Examinations were performed on 21 A-bomb survivors (10 males and 11 females) and 11 controls (5 males and 6 females). Colony formation of hemopoietic stem cells (granulocyte/monocyte-colony-forming cells, GM-CFC and burst-forming unit-erythrocytes, BFU-E) was made by the methylcellulose method patterned after the methods of Iscove et al and Ogawa et al using 5 - 10 ml of peripheral blood. Chromosome specimens were prepared from single colonies by the micromethod which we have reported elsewhere. The total number of colonies analyzed in the exposed group was 131 GM-CFC and 75 BFU-E. Chromosome abnormalities were observed in 15 (11.5 %) and 9 (12.0 %) colonies, respectively. In the control group, the total number of colonies analyzed was 61 GM-CFC and 41 BFU-E, but none of the colonies showed chromosome abnormalities. A highly significant difference in chromosome abnormalities was demonstrated by an exact test with a probability of 0.3 % for GM-CFC and 1.7 % for BFU-E. The karyotypes of chromosome abnormalities obtained from the colonies of hemopoietic stem cells in the exposed group were mostly translocations, but deletion and marker chromosomes were also observed. In two individuals, such karyotypic abnormalities as observed in the peripheral lymphocytes were seen also in the hemopoietic precursor cells. This finding suggests that radiation may produce an effect even on relatively undifferentiated hemopoietic stem cells. (author)

  20. Peripheral blood stem cell harvest in patients with limited stage small-cell lung cancer

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    Katakami, Nobuyuki; Takakura, Shunji; Fujii, Hiroshi; Nishimura, Takashi; Umeda, Bunichi [Kobe City General Hospital (Japan)

    2000-06-01

    Chemotherapy plus granulocyte colony-stimulating factor (G-CSF) induced mobilization of peripheral blood stem cells (PBSC) was performed in patients with limited stage small-cell lung cancer. Chemotherapy consisted of cisplatin/etoposide or cisplatin/adriamycin/etoposide. The amounts of CD34 positive cells and granulocyte-macrophage colony forming units (CFU-GM) collected during 2-3 courses of apheresis were 3.1{+-}2.9 x 10{sup 6}/kg (n=10) and 3.1{+-}1.5 x 10{sup 5}/kg (n=8) , respectively. Adequate amounts of PBSC were also harvested even in patients treated with concurrent chemoradiotherapy. Eight patients were successfully treated with high-dose chemotherapy consisting of ifosfamide, carboplatin and etoposide with PBSC transfusion. The patients'-bone marrow reconstruction was rapid and no treatment-related death was observed. (author)

  1. Endothelial Cells Promote Expansion of Long-Term Engrafting Marrow Hematopoietic Stem and Progenitor Cells in Primates.

    Science.gov (United States)

    Gori, Jennifer L; Butler, Jason M; Kunar, Balvir; Poulos, Michael G; Ginsberg, Michael; Nolan, Daniel J; Norgaard, Zachary K; Adair, Jennifer E; Rafii, Shahin; Kiem, Hans-Peter

    2017-03-01

    Successful expansion of bone marrow (BM) hematopoietic stem and progenitor cells (HSPCs) would benefit many HSPC transplantation and gene therapy/editing applications. However, current expansion technologies have been limited by a loss of multipotency and self-renewal properties ex vivo. We hypothesized that an ex vivo vascular niche would provide prohematopoietic signals to expand HSPCs while maintaining multipotency and self-renewal. To test this hypothesis, BM autologous CD34 + cells were expanded in endothelial cell (EC) coculture and transplanted in nonhuman primates. CD34 + C38 - HSPCs cocultured with ECs expanded up to 17-fold, with a significant increase in hematopoietic colony-forming activity compared with cells cultured with cytokines alone (colony-forming unit-granulocyte-erythroid-macrophage-monocyte; p < .005). BM CD34 + cells that were transduced with green fluorescent protein lentivirus vector and expanded on ECs engrafted long term with multilineage polyclonal reconstitution. Gene marking was observed in granulocytes, lymphocytes, platelets, and erythrocytes. Whole transcriptome analysis indicated that EC coculture altered the expression profile of 75 genes in the BM CD34 + cells without impeding the long-term engraftment potential. These findings show that an ex vivo vascular niche is an effective platform for expansion of adult BM HSPCs. Stem Cells Translational Medicine 2017;6:864-876. © 2016 The Authors Stem Cells Translational Medicine published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

  2. Mobilization and collection of CD34+ cells for autologous transplantation of peripheral blood hematopoietic progenitor cells in children: analysis of two different granulocyte-colony stimulating factor doses

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    Kátia Aparecida de Brito Eid

    2015-06-01

    Full Text Available Introduction: The use of peripheral hematopoietic progenitor cells (HPCs is the cell choice in autologous transplantation. The classic dose of granulocyte-colony stimulating factor (G- CSF for mobilization is a single daily dose of 10 µg/kg of patient body weight. There is a theory that higher doses of granulocyte-colony stimulating factor applied twice daily could increase the number of CD34+ cells collected in fewer leukapheresis procedures. Objective: The aim of this study was to compare a fractionated dose of 15 µg G-CSF/kg of body weight and the conventional dose of granulocyte-colony stimulating factor in respect to the number of leukapheresis procedures required to achieve a minimum collection of 3 × 106 CD34+ cells/kg body weight. Methods: Patients were divided into two groups: Group 10 - patients who received a single daily dose of 10 µg G-CSF/kg body weight and Group 15 - patients who received a fractioned dose of 15 µg G-CSF/kg body weight daily. The leukapheresis procedure was carried out in an automated cell separator. The autologous transplantation was carried out when a minimum number of 3 × 106 CD34+ cells/kg body weight was achieved. Results: Group 10 comprised 39 patients and Group 15 comprised 26 patients. A total of 146 apheresis procedures were performed: 110 (75.3% for Group 10 and 36 (24.7% for Group 15. For Group 10, a median of three (range: 1-7 leukapheresis procedures and a mean of 8.89 × 106 CD34+ cells/kg body weight (±9.59 were collected whereas for Group 15 the corresponding values were one (range: 1-3 and 5.29 × 106 cells/kg body weight (±4.95. A statistically significant difference was found in relation to the number of apheresis procedures (p-value <0.0001. Conclusions: To collect a minimum target of 3 × 106 CD34+ cells/kg body weight, the administration of a fractionated dose of 15 µg G-CSF/kg body weight significantly decreased the number of leukapheresis procedures performed.

  3. Evaluation of drug-induced hematotoxicity using novel in vitro monkey CFU-GM and BFU-E colony assays.

    Science.gov (United States)

    Goto, Koichi; Goto, Mayumi; Ando-Imaoka, Masako; Kai, Kiyonori; Mori, Kazuhiko

    2017-01-01

    In order to evaluate drug-induced hematotoxicity in monkey cells in vitro, colony-forming unit-granulocyte, macrophage (CFU-GM), and burst-forming unit-erythroid (BFU-E) colony assays were established using mononuclear cells in the bone marrow collected from male cynomolgus monkeys. Furthermore, the effects of doxorubicin, chloramphenicol, and linezolid on CFU-GM and BFU-E colony formation were investigated using established monkey CFU-GM and BFU-E colony assays in comparison with those on human CFU-GM and BFU-E colonies acquired from human umbilical cord blood cells. Bone marrow mononuclear cells were collected from the ischial or iliac bone of male cynomolgus monkeys. The cells were subsequently processed by density gradient separation at 1.067, 1.070, or 1.077 g/mL for CFU-GM or 1.077 g/mL for BFU-E, and then cultured in methylcellulose medium for 9 or 13 days, respectively. A sufficient number of CFU-GM colonies were formed from mononuclear cells processed at a density of 1.070 g/mL. Moreover, the number of BFU-E colonies from the cells processed at a density of 1.077 g/mL was sufficient for the colony assay. The number of CFU-GM or BFU-E colonies decreased after treatment with the drugs of interest in a concentration-dependent manner. Compared with human CFU-GM, monkey CFU-GM were more sensitive to chloramphenicol and resistant to doxorubicin, whereas monkey BFU-E were more sensitive to all compounds in comparison to the sensitivity of human BFU-E. In conclusion, monkey CFU-GM and BFU-E colony assays were established and considered useful tools to evaluate the differences in drug-induced hematotoxicity between species.

  4. Long-active granulocyte colony-stimulating factor for peripheral blood hematopoietic progenitor cell mobilization.

    Science.gov (United States)

    Martino, Massimo; Laszlo, Daniele; Lanza, Francesco

    2014-06-01

    Peg-filgrastim (PEG-FIL), a polyethylene glycol-conjugated form of granulocyte colony-stimulating factor (G-CSF), has been introduced in clinical practice and is effective in shortening the time of neutropenia after cytotoxic chemotherapy. G-CSF has emerged as the preferred cytokine for hematopoietic progenitor cells' (HPC) mobilization. Nevertheless, data on the ability of PEG-FIL in this field have been published. We review publications in the field with the goal of providing an overview of this approach. PEG-FIL may be able to mobilize CD34(+) cells in a more timely fashion than G-CSF, with the advantages of only a single-dose administration, an earlier start and a reduction in the number of apheresis procedures. The main controversies concern the dosage of the drug and the optimal dose. In the context of chemo-mobilization, a single dose of 6 mg PEG-FIL seems effective in terms of HPC's mobilization and there is no increase in this effect if the dose is doubled to 12 mg. Steady-state mobilization requires higher doses of PEG-FIL and this approach is not cost-effective when compared with G-CSF. The experiences with PEG-FIL in the healthy donor setting are very limited.

  5. Isolation of hemopoietic stem cell subsets from murine bone marrow: II. Evidence for an early precursor of day-12 CFU-S and cells associated with radioprotective ability

    International Nuclear Information System (INIS)

    Ploemacher, R.E.; Brons, N.H.

    1988-01-01

    Counterflow centrifugal elutriation (CCE) in combination with plastic adherence and fluorescence-activated cell sorting were used consecutively to enrich functionally different subpopulations of pluripotent hemopoietic stem cells (HSC) from mouse bone marrow. The nonadherent CCE fractions were labeled with wheat germ agglutinin (WGA)-fluorescein isothiocyanate (FITC) and sorted according to differences in fluorescence within various windows on the basis of forward (FLS) and perpendicular (PLS) light scatter. The sorted cells were then assayed for their (1) in vivo colony-forming ability (day-7 and day-12 spleen colony-forming units [CFU-S]), (2) radioprotective ability (RPA; 30-day survival), and (3) their ability to repopulate the bone marrow or spleen over a 13-day period with day-12 CFU-S, granulocyte-macrophage colony-forming units (CFU-GM), nucleated cells, or cells associated with RPA. The highest incidence of day-12 CFU-S and cells with RPA was obtained by sorting the most WGA-positive cells with relatively high PLS (enrichment, 50- to 200-fold), lowering the effective dose (ED 50/30) to an average of 80 cells. The separative procedure enabled hemopoietic stem cells that repopulate both bone marrow and spleen with secondary RPA cells, CFU-S-12, and CFU-GM to be enriched and separated from part of the RPA cells, CFU-S-12, and cells that reconstitute the cellularity of bone marrow and spleen. These data suggest that cells generating both day-12 CFU-S and RPA cells differ from day-12 CFU-S and RPA cells themselves on the basis of PLS characteristics and affinity for WGA. Such early stem cells have also been detected in sorted fractions meeting the FLS/PLS characteristics of lymphocytes

  6. Clonal proliferation of multipotent stem/progenitor cells in the neonatal and adult salivary glands

    International Nuclear Information System (INIS)

    Kishi, Teruki; Takao, Tukasa; Fujita, Kiyohide; Taniguchi, Hideki

    2006-01-01

    Salivary gland stem/progenitor cells are thought to be present in intercalated ductal cells, but the fact is unclear. In this study, we sought to clarify if stem/progenitor cells are present in submandibular glands using colony assay, which is one of the stem cell assay methods. Using a low-density culture of submandibular gland cells of neonatal rats, we developed a novel culture system that promotes single cell colony formation. Average doubling time for the colony-forming cells was 24.7 (SD = ±7.02) h, indicating high proliferative potency. When epidermal growth factor (EGF) and hepatocyte growth factor (HGF) were added to the medium, the number of clonal colonies increased greater than those cultured without growth factors (13.2 ± 4.18 vs. 4.5 ± 1.73). The RT-PCR and immunostaining demonstrated expressing acinar, ductal, and myoepithelial cell lineage markers. This study demonstrated the presence of the salivary gland stem/progenitor cells that are highly proliferative and multipotent in salivary glands

  7. Formation of large colonies: a defense mechanism of Microcystis aeruginosa under continuous grazing pressure by flagellate Ochromonas sp.

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    Fanxiang Kong

    2012-01-01

    Full Text Available Induced colony formation under grazing pressure has been reported in our previous results. However, the colonies induced in these studies comprised only tens of cells which are far smaller than the naturally occurring colonies. In this work, unicellular Microcystis aeruginosa Kützing were co-cultivated with flagellate Ochromonas sp. for 50 d to investigate colony formation in M. aeruginosa under continuous grazing pressure. Results revealed that colonial M. aeruginosa formed on the 10th d under the grazing pressure of flagellate. These algal colonies resulted from the daughter cells of freshly dividing cells that failed to separate during the reproductive process. The diameters and cell numbers of the colonies increased slowly with time. Under continuous grazing pressure by Ochromonas sp. for 50 d, the diameter of some colonies reached over 180 μm. Analysis showed that the extracellular polysaccharide (EPS content and relative gas vesicle (RGV of each cell increased significantly after colony formation. However, there was no significant difference on the monosaccharide composition between unicellular and colonial M. aeruginosa. The loose aggregation of cells in the floating colonies suggests that a correlation probably exists between cell compactness and colony buoyancy.

  8. Identification of rabbit annulus fibrosus-derived stem cells.

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    Chen Liu

    Full Text Available Annulus fibrosus (AF injuries can lead to substantial deterioration of intervertebral disc (IVD which characterizes degenerative disc disease (DDD. However, treatments for AF repair/regeneration remain challenging due to the intrinsic heterogeneity of AF tissue at cellular, biochemical, and biomechanical levels. In this study, we isolated and characterized a sub-population of cells from rabbit AF tissue which formed colonies in vitro and could self-renew. These cells showed gene expression of typical surface antigen molecules characterizing mesenchymal stem cells (MSCs, including CD29, CD44, and CD166. Meanwhile, they did not express negative markers of MSCs such as CD4, CD8, and CD14. They also expressed Oct-4, nucleostemin, and SSEA-4 proteins. Upon induced differentiation they showed typical osteogenesis, chondrogenesis, and adipogenesis potential. Together, these AF-derived colony-forming cells possessed clonogenicity, self-renewal, and multi-potential differentiation capability, the three criteria characterizing MSCs. Such AF-derived stem cells may potentially be an ideal candidate for DDD treatments using cell therapies or tissue engineering approaches.

  9. Characterization of a resident population of adventitial macrophage progenitor cells in postnatal vasculature.

    Science.gov (United States)

    Psaltis, Peter J; Puranik, Amrutesh S; Spoon, Daniel B; Chue, Colin D; Hoffman, Scott J; Witt, Tyra A; Delacroix, Sinny; Kleppe, Laurel S; Mueske, Cheryl S; Pan, Shuchong; Gulati, Rajiv; Simari, Robert D

    2014-07-18

    Macrophages regulate blood vessel structure and function in health and disease. The origins of tissue macrophages are diverse, with evidence for local production and circulatory renewal. We identified a vascular adventitial population containing macrophage progenitor cells and investigated their origins and fate. Single-cell disaggregates from adult C57BL/6 mice were prepared from different tissues and tested for their capacity to form hematopoietic colony-forming units. Aorta showed a unique predilection for generating macrophage colony-forming units. Aortic macrophage colony-forming unit progenitors coexpressed stem cell antigen-1 and CD45 and were adventitially located, where they were the predominant source of proliferating cells in the aortic wall. Aortic Sca-1(+)CD45(+) cells were transcriptionally and phenotypically distinct from neighboring cells lacking stem cell antigen-1 or CD45 and contained a proliferative (Ki67(+)) Lin(-)c-Kit(+)CD135(-)CD115(+)CX3CR1(+)Ly6C(+)CD11b(-) subpopulation, consistent with the immunophenotypic profile of macrophage progenitors. Adoptive transfer studies revealed that Sca-1(+)CD45(+) adventitial macrophage progenitor cells were not replenished via the circulation from bone marrow or spleen, nor was their prevalence diminished by depletion of monocytes or macrophages by liposomal clodronate treatment or genetic deficiency of macrophage colony-stimulating factor. Rather adventitial macrophage progenitor cells were upregulated in hyperlipidemic ApoE(-/-) and LDL-R(-/-) mice, with adventitial transfer experiments demonstrating their durable contribution to macrophage progeny particularly in the adventitia, and to a lesser extent the atheroma, of atherosclerotic carotid arteries. The discovery and characterization of resident vascular adventitial macrophage progenitor cells provides new insight into adventitial biology and its participation in atherosclerosis and provokes consideration of the broader existence of local macrophage

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

    Energy Technology Data Exchange (ETDEWEB)

    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)

  11. Cell kinetics of GM-CFC in the steady state

    International Nuclear Information System (INIS)

    Hagan, M.P.; MacVittie, T.J.; Dodgen, D.P.

    1985-01-01

    The kinetics of cell turnover for myeloid/monocyte cells that form colonies in agar (GM-CFC) were measured through the progressive increase in their sensitivity to 313-nm light during a period of cell labeling with BrdCyd. Two components of cell killing with distinctly separate labeling kinetics revealed both the presence of two generations within the GM-CFC compartment and the properties of the kinetics of the precursors of the GM-CFC. These precursors of the GM-CFC were not assayable in a routine GM-CFC assay when pregnant mouse uterus extract and mouse L-cell-conditioned medium were used to stimulate colony formation but were revealed by the labeling kinetics of the assayable GM-CFC. Further, these precursor cells appeared to enter the assayable GM-CFC population from a noncycling state. This was evidenced by the failure of the majority of these cells to incorporate BrdCyd during five days of infusion. The half-time for cell turnover within this precursor compartment was measured to be approximately 5.5 days. Further, these normally noncycling cells proliferated rapidly in response to endotoxin. High-proliferative-potential colony-forming cells (HPP-CFC) were tested as a candidate for this precursor population. The results of the determination of the kinetics for these cells showed that the HPP-CFC exist largely in a Go state, existing at an average rate of once every four days. The slow turnover time for these cells and their response to endotoxin challenge are consistent with a close relationship between the HPP-CFC and the Go pool of cells that is the direct precursor of the GM-CFC

  12. Blue light inhibits the growth of B16 melanoma cells

    International Nuclear Information System (INIS)

    Ohara, Masayuki; Katoh, Osamu; Watanabe, Hiromitsu

    2002-01-01

    Although a number of studies have been carried out to examine the biological effects of radiation and ultraviolet radiation (UV), little is known concerning the effects of visible light. In the present study, exposure of B16 melanoma cells to blue light (wavelength 470 nm, irradiance 5.7 mW/cm 2 ) from a light-emitting diode (LED) inhibited cell growth in proportion to the period of exposure, with no increase observed in the number of dead cells. The number of B16 melanoma colonies that formed after exposure to blue light for 20 min was only slightly less than that in non-exposed controls, but the colony size as assessed by the area covered by colonies and cell counts per colony were markedly decreased. The percentages of G0/G1 and G2/M phase cells were markedly increased, with a reduction in S phase cells as determined by flow cytometry after exposure to blue light. Furthermore, analysis of the incorporation of 5-bromo-2'-deoxyuridine (BrdU) into DNA also showed a reduction in the percentage of S phase cells after exposure. These results indicate that blue light exerts cytostatic effects, but not a cytocidal action, on B16 melanoma cells. (author)

  13. Blue light inhibits the growth of B16 melanoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Ohara, Masayuki; Katoh, Osamu; Watanabe, Hiromitsu [Hiroshima Univ. (Japan). Research Inst. for Radiation Biology and Medicine; Kawashima, Yuzo [Otsuka Pharmaceutical Factory, Inc., Naruto, Tokushima (Japan)

    2002-05-01

    Although a number of studies have been carried out to examine the biological effects of radiation and ultraviolet radiation (UV), little is known concerning the effects of visible light. In the present study, exposure of B16 melanoma cells to blue light (wavelength 470 nm, irradiance 5.7 mW/cm{sup 2}) from a light-emitting diode (LED) inhibited cell growth in proportion to the period of exposure, with no increase observed in the number of dead cells. The number of B16 melanoma colonies that formed after exposure to blue light for 20 min was only slightly less than that in non-exposed controls, but the colony size as assessed by the area covered by colonies and cell counts per colony were markedly decreased. The percentages of G0/G1 and G2/M phase cells were markedly increased, with a reduction in S phase cells as determined by flow cytometry after exposure to blue light. Furthermore, analysis of the incorporation of 5-bromo-2'-deoxyuridine (BrdU) into DNA also showed a reduction in the percentage of S phase cells after exposure. These results indicate that blue light exerts cytostatic effects, but not a cytocidal action, on B16 melanoma cells. (author)

  14. Establishment of automated culture system for murine induced pluripotent stem cells

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    Koike Hiroyuki

    2012-11-01

    Full Text Available Abstract Background Induced pluripotent stem (iPS cells can differentiate into any cell type, which makes them an attractive resource in fields such as regenerative medicine, drug screening, or in vitro toxicology. The most important prerequisite for these industrial applications is stable supply and uniform quality of iPS cells. Variation in quality largely results from differences in handling skills between operators in laboratories. To minimize these differences, establishment of an automated iPS cell culture system is necessary. Results We developed a standardized mouse iPS cell maintenance culture, using an automated cell culture system housed in a CO2 incubator commonly used in many laboratories. The iPS cells propagated in a chamber uniquely designed for automated culture and showed specific colony morphology, as for manual culture. A cell detachment device in the system passaged iPS cells automatically by dispersing colonies to single cells. In addition, iPS cells were passaged without any change in colony morphology or expression of undifferentiated stem cell markers during the 4 weeks of automated culture. Conclusions Our results show that use of this compact, automated cell culture system facilitates stable iPS cell culture without obvious effects on iPS cell pluripotency or colony-forming ability. The feasibility of iPS cell culture automation may greatly facilitate the use of this versatile cell source for a variety of biomedical applications.

  15. Single-cell printing to form three-dimensional lines of olfactory ensheathing cells

    International Nuclear Information System (INIS)

    Othon, Christina M; Ringeisen, Bradley R; Wu Xingjia; Anders, Juanita J

    2008-01-01

    Biological laser printing (BioLP(TM)) is a unique tool capable of printing high resolution two- and three-dimensional patterns of living mammalian cells, with greater than 95% viability. These results have been extended to primary cultured olfactory ensheathing cells (OECs), harvested from adult Sprague-Dawley rats. OECs have been found to provide stimulating environments for neurite outgrowth in spinal cord injury models. BioLP is unique in that small load volumes (∼μLs) are required to achieve printing, enabling low numbers of OECs to be harvested, concentrated and printed. BioLP was used to form several 8 mm lines of OECs throughout a multilayer hydrogel scaffold. The line width was as low as 20 μm, with most lines comprising aligned single cells. Fluorescent confocal microscopy was used to determine the functionality of the printed OECs, to monitor interactions between printed OECs, and to determine the extent of cell migration throughout the 3D scaffold. High-resolution printing of low cell count, harvested OECs is an important advancement for in vitro study of cell interactions and functionality. In addition, these cell-printed scaffolds may provide an alternative for spinal cord repair studies, as the single-cell patterns formed here are on relevant size scales for neurite outgrowth

  16. Yeast Colonies: A Model for Studies of Aging, Environmental Adaptation, and Longevity

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    Libuše Váchová

    2012-01-01

    Full Text Available When growing on solid surfaces, yeast, like other microorganisms, develops organized multicellular populations (colonies and biofilms that are composed of differentiated cells with specialized functions. Life within these populations is a prevalent form of microbial existence in natural settings that provides the cells with capabilities to effectively defend against environmental attacks as well as efficiently adapt and survive long periods of starvation and other stresses. Under such circumstances, the fate of an individual yeast cell is subordinated to the profit of the whole population. In the past decade, yeast colonies, with their complicated structure and high complexity that are also developed under laboratory conditions, have become an excellent model for studies of various basic cellular processes such as cell interaction, signaling, and differentiation. In this paper, we summarize current knowledge on the processes related to chronological aging, adaptation, and longevity of a colony cell population and of its differentiated cell constituents. These processes contribute to the colony ability to survive long periods of starvation and mostly differ from the survival strategies of individual yeast cells.

  17. Colony formation in the cyanobacterium Microcystis.

    Science.gov (United States)

    Xiao, Man; Li, Ming; Reynolds, Colin S

    2018-02-22

    Morphological evolution from a unicellular to multicellular state provides greater opportunities for organisms to attain larger and more complex living forms. As the most common freshwater cyanobacterial genus, Microcystis is a unicellular microorganism, with high phenotypic plasticity, which forms colonies and blooms in lakes and reservoirs worldwide. We conducted a systematic review of field studies from the 1990s to 2017 where Microcystis was dominant. Microcystis was detected as the dominant genus in waterbodies from temperate to subtropical and tropical zones. Unicellular Microcystis spp. can be induced to form colonies by adjusting biotic and abiotic factors in laboratory. Colony formation by cell division has been induced by zooplankton filtrate, high Pb 2+ concentration, the presence of another cyanobacterium (Cylindrospermopsis raciborskii), heterotrophic bacteria, and by low temperature and light intensity. Colony formation by cell adhesion can be induced by zooplankton grazing, high Ca 2+ concentration, and microcystins. We hypothesise that single cells of all Microcystis morphospecies initially form colonies with a similar morphology to those found in the early spring. These colonies gradually change their morphology to that of M. ichthyoblabe, M. wesenbergii and M. aeruginosa with changing environmental conditions. Colony formation provides Microcystis with many ecological advantages, including adaption to varying light, sustained growth under poor nutrient supply, protection from chemical stressors and protection from grazing. These benefits represent passive tactics responding to environmental stress. Microcystis colonies form at the cost of decreased specific growth rates compared with a unicellular habit. Large colony size allows Microcystis to attain rapid floating velocities (maximum recorded for a single colony, ∼ 10.08 m h -1 ) that enable them to develop and maintain a large biomass near the surface of eutrophic lakes, where they may shade

  18. Inhibitory Effects of Salinomycin on Cell Survival, Colony Growth, Migration, and Invasion of Human Non-Small Cell Lung Cancer A549 and LNM35: Involvement of NAG-1.

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    Kholoud Arafat

    Full Text Available A major challenge for oncologists and pharmacologists is to develop more potent and less toxic drugs that will decrease the tumor growth and improve the survival of lung cancer patients. Salinomycin is a polyether antibiotic used to kill gram-positive bacteria including mycobacteria, protozoans such as plasmodium falciparum, and the parasites responsible for the poultry disease coccidiosis. This old agent is now a serious anti-cancer drug candidate that selectively inhibits the growth of cancer stem cells. We investigated the impact of salinomycin on survival, colony growth, migration and invasion of the differentiated human non-small cell lung cancer lines LNM35 and A549. Salinomycin caused concentration- and time-dependent reduction in viability of LNM35 and A549 cells through a caspase 3/7-associated cell death pathway. Similarly, salinomycin (2.5-5 µM for 7 days significantly decreased the growth of LNM35 and A549 colonies in soft agar. Metastasis is the main cause of death related to lung cancer. In this context, salinomycin induced a time- and concentration-dependent inhibition of cell migration and invasion. We also demonstrated for the first time that salinomycin induced a marked increase in the expression of the pro-apoptotic protein NAG-1 leading to the inhibition of lung cancer cell invasion but not cell survival. These findings identify salinomycin as a promising novel therapeutic agent for lung cancer.

  19. EXAMINATION OF THE GERM CELL CHIMERA FORMING POTENTIAL OF MOUSE EMBRYONIC STEM CELLS

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    V.B. CÂRSTEA

    2007-05-01

    Full Text Available The aim of this study was to examine the factors, which influence the chimeraforming potential of mouse embryonic stem cells (ES cells. In our work, we examinethe chimera producing ability of R1 and R1/E mouse ES cell lines. We found that thepassage number affects chimera-forming capability of the ES cells. With theincreasing of the passage number, it could be getting less chimera animal, and onlythe R1/E ES cell line derived cells could contribute to the germ cells. At first, wecompared the marker of pluripotency using immunostaining and RT PCR, but wecould not find any difference between the R1 and R1/E cell in this way. Atchromosome analysis, we found, that the number of aneuploid cells, in R1 ES cellline, dramatically increased after 10 passages. We thought that the reason is thatduring the cell division Y chromosome could not arrange correctly between the twonewly derived progeny cells. To prove our conception, we made X and YchromosomeFISH analyses. We found, that the aneuploid R1 and R1/E ES cellscontain only one X and one Y chromosome, so not the loss of Y chromosome causethe problem at the germ cell formation. At last, we made the karyotypeanalysis of R1 and R1/E ES cells at different passages. The karyotype analysisdemonstrated that in the case of R1 ES cell line, the 41 and 42-chromosomecontaining cells hold trisomy. With the increasing of the passages number, thenumber of trisomy containing aneuploid cells increased. The aneuploid ES cells cancontribute to the different tissuses of chimera animals, but cannot form viable germcells.

  20. EXAMINATION OF THE GERM CELL CHIMERA FORMING POTENTIAL OF MOUSE EMBRYONIC STEM CELLS

    Directory of Open Access Journals (Sweden)

    CÂRSTEA V. B

    2007-01-01

    Full Text Available The aim of this study was to examine the factors, which influence the chimeraforming potential of mouse embryonic stem cells (ES cells. In our work, we examinethe chimera producing ability of R1 and R1/E mouse ES cell lines. We found that thepassage number affects chimera-forming capability of the ES cells. With theincreasing of the passage number, it could be getting less chimera animal, and onlythe R1/E ES cell line derived cells could contribute to the germ cells. At first, wecompared the marker of pluripotency using immunostaining and RT PCR, but wecould not find any difference between the R1 and R1/E cell in this way. Atchromosome analysis, we found, that the number of aneuploid cells, in R1 ES cellline, dramatically increased after 10 passages. We thought that the reason is thatduring the cell division Y chromosome could not arrange correctly between the twonewly derived progeny cells. To prove our conception, we made X and YchromosomeFISH analyses. We found, that the aneuploid R1 and R1/E ES cellscontain only one X and one Y chromosome, so not the loss of Y chromosome causethe problem at the germ cell formation. At last, we made the karyotypeanalysis of R1 and R1/E ES cells at different passages. The karyotype analysisdemonstrated that in the case of R1 ES cell line, the 41 and 42-chromosomecontaining cells hold trisomy. With the increasing of the passages number, thenumber of trisomy containing aneuploid cells increased. The aneuploid ES cells cancontribute to the different tissuses of chimera animals, but cannot form viable germcells.

  1. Response to high LET radiation 12C (LET, 295 keV/microm) in M5 cells, a radio resistant cell strain derived from Chinese hamster V79 cells.

    Science.gov (United States)

    Pathak, R; Sarma, A; Sengupta, B; Dey, S K; Khuda-Bukhsh, A R

    2007-01-01

    To study the effects of 12C-beam of 295 keV/microm (57.24 MeV) on M5 and Chinese hamster V79 cells by using cytogenetic assays like micronuclei (MN) induction, chromosomal aberrations (CA) and apoptosis. Additionally, the relative survival of these two cell lines was tested by the colony forming ability of the cells, with a view to understanding the mechanism of cellular damages that lead to difference in cell survival. Confluent cells were irradiated with 12C-beam at various doses using 15UD Pelletron accelerator. Cell survival was studied by the colony forming ability of cells. MN assay was done by fluorescent staining. Different types of chromosomal aberrations in metaphase cells were scored at 12 h after irradiation. Apoptosis was measured at different post irradiation times as detected by nuclear fragmentation and DNA ladder was prepared after 48 h of incubation. Dose-dependent decrease in surviving fractions was found in both the cell lines. However, the surviving fractions were higher in M5 cells in comparison to V79 cells when exposed to the same radiation doses. On the other hand, induced MN frequencies, CA frequencies and apoptosis percentages were less in M5 cells than V79 cells. Very good correlations between surviving fractions and induced MN frequencies or induced total CA or induced apoptosis percentages were obtained in this study. The cell strain M5 showed relatively more radio-resistance to 12C-beam compared to Chinese hamster V79 cells in this study. As the MN formation, CA and apoptosis induction were less in M5 cells as compared to parental V79 cells, the higher cell survival in the former could possibly be attributed to their better repairing ability leading to higher cell survival.

  2. Colony form variation of Bacillus pumilus E601 after cultured and neutron irradiation

    International Nuclear Information System (INIS)

    Chen Xiaoming; Wei Baoli; Zhang Jianguo

    2008-01-01

    The distribution of two colony forms of Bacillus pumilus E601 and the effect of neutron irradiation on the colony form were reported. The translucent and opaque colonies were cultured several generations to observe the proportion of two form colonies. The spores of opaque colony were irradiated at 80, 800 and 2000 Gy of fast neutron from CFBR-II pulse pile, and the survivors of opaque colony were irradiated again at the same doses. The results showed that: (1) Bacillus pumilus E601 observed two types of colony form: translucent and opaque colony; (2) the translucent colony could produce both translucent and opaque colonies in equal, while the opaque colony couldn't produce translucent colony generally; (3) neutron irradiation could affect the colony form distribution. The ratio of survival translucent colony was increased with the increase of the first neutron irradiation doses, and the second neutron irradiation also increased the ratio of translucent colony. It was concluded that the instability of translucent colony was the main reason to produce two colony forms of Bacillus pumilus E601. The strain of translucent colony had a stronger ability to resist neutron irradiation than the opaque colony. (authors)

  3. Left-right asymmetry is formed in individual cells by intrinsic cell chirality.

    Science.gov (United States)

    Hatori, Ryo; Ando, Tadashi; Sasamura, Takeshi; Nakazawa, Naotaka; Nakamura, Mitsutoshi; Taniguchi, Kiichiro; Hozumi, Shunya; Kikuta, Junichi; Ishii, Masaru; Matsuno, Kenji

    2014-08-01

    Many animals show left-right (LR) asymmetric morphology. The mechanisms of LR asymmetric development are evolutionarily divergent, and they remain elusive in invertebrates. Various organs in Drosophila melanogaster show stereotypic LR asymmetry, including the embryonic gut. The Drosophila embryonic hindgut twists 90° left-handedly, thereby generating directional LR asymmetry. We recently revealed that the hindgut epithelial cell is chiral in shape and other properties; this is termed planar cell chirality (PCC). We previously showed by computer modeling that PCC is sufficient to induce the hindgut rotation. In addition, both the PCC and the direction of hindgut twisting are reversed in Myosin31DF (Myo31DF) mutants. Myo31DF encodes Drosophila MyosinID, an actin-based motor protein, whose molecular functions in LR asymmetric development are largely unknown. Here, to understand how PCC directs the asymmetric cell-shape, we analyzed PCC in genetic mosaics composed of cells homozygous for mutant Myo31DF, some of which also overexpressed wild-type Myo31DF. Wild-type cell-shape chirality only formed in the Myo31DF-overexpressing cells, suggesting that cell-shape chirality was established in each cell and reflects intrinsic PCC. A computer model recapitulating the development of this genetic mosaic suggested that mechanical interactions between cells are required for the cell-shape behavior seen in vivo. Our mosaic analysis also suggested that during hindgut rotation in vivo, wild-type Myo31DF suppresses the elongation of cell boundaries, supporting the idea that cell-shape chirality is an intrinsic property determined in each cell. However, the amount and distribution of F-actin and Myosin II, which are known to help generate the contraction force on cell boundaries, did not show differences between Myo31DF mutant cells and wild-type cells, suggesting that the static amount and distribution of these proteins are not involved in the suppression of cell-boundary elongation

  4. Growth of cells superinoculated onto irradiated and nonirradiated confluent monolayers

    International Nuclear Information System (INIS)

    Matsuoka, H.; Ueo, H.; Sugimachi, K.

    1990-01-01

    We prepared confluent monolayers of normal BALB/c 3T3 cells and compared differences in the growth of four types of cells superinoculated onto these nonirradiated and irradiated monolayers. The test cells were normal BALB/c 3T3 A31 cells, a squamous cell carcinoma from a human esophageal cancer (KSE-1), human fetal fibroblasts, and V-79 cells from Chinese hamster lung fibroblasts. Cell growth was checked by counting the cell number, determining [3H]thymidine incorporation and assessing colony formation. We found that on nonirradiated monolayers, colony formation of human fetal fibroblasts and normal BALB/c 3T3 cells was completely inhibited. On irradiated cells, test cells did exhibit some growth. KSE-1 cells, which had a low clonogenic efficiency on plastic surfaces, formed colonies on both irradiated and nonirradiated cells. On these monolayers, the clonogenic efficiency of V-79 cells was also higher than that on plastic surfaces. We conclude that the nonirradiated monolayer of BALB/c 3T3 cells completely inhibits the growth of superinoculated normal BALB/c 3T3 and human fetal fibroblasts, while on the other hand, they facilitate the growth of neoplastic KSE-1 and V-79 cells by providing a surface for cell adherence and growth, without affecting the presence of normal cells in co-cultures

  5. Adaptive T cell responses induced by oncolytic Herpes Simplex Virus-granulocyte macrophage-colony-stimulating factor therapy expanded by dendritic cell and cytokine-induced killer cell adoptive therapy.

    Science.gov (United States)

    Ren, Jun; Gwin, William R; Zhou, Xinna; Wang, Xiaoli; Huang, Hongyan; Jiang, Ni; Zhou, Lei; Agarwal, Pankaj; Hobeika, Amy; Crosby, Erika; Hartman, Zachary C; Morse, Michael A; H Eng, Kevin; Lyerly, H Kim

    2017-01-01

    Purpose : Although local oncolytic viral therapy (OVT) may enhance tumor lysis, antigen release, and adaptive immune responses, systemic antitumor responses post-therapy are limited. Adoptive immunotherapy with autologous dendritic cells (DC) and cytokine-induced killer cells (DC-CIK) synergizes with systemic therapies. We hypothesized that OVT with Herpes Simplex Virus-granulocyte macrophage-colony-stimulating factor (HSV-GM-CSF) would induce adaptive T cell responses that could be expanded systemically with sequential DC-CIK therapy. Patients and Methods : We performed a pilot study of intratumoral HSV-GM-CSF OVT followed by autologous DC-CIK cell therapy. In addition to safety and clinical endpoints, we monitored adaptive T cell responses by quantifying T cell receptor (TCR) populations in pre-oncolytic therapy, post-oncolytic therapy, and after DC-CIK therapy. Results : Nine patients with advanced malignancy were treated with OVT (OrienX010), of whom seven experienced stable disease (SD). Five of the OVT treated patients underwent leukapheresis, generation, and delivery of DC-CIKs, and two had SD, whereas three progressed. T cell receptor sequencing of TCR β sequences one month after OVT therapy demonstrates a dynamic TCR repertoire in response to OVT therapy in the majority of patients with the systematic expansion of multiple T cell clone populations following DC-CIK therapy. This treatment was well tolerated and long-term event free and overall survival was observed in six of the nine patients. Conclusions : Strategies inducing the local activation of tumor-specific immune responses can be combined with adoptive cellular therapies to expand the adaptive T cell responses systemically and further studies are warranted.

  6. Effect of hydroxyurea and vinblastine on the proliferation of the pluripotential stem cells

    International Nuclear Information System (INIS)

    Necas, E.; Neuwirt, J.

    1977-01-01

    The population of the pluripotential hemopoietic stem cells in mice, i.e., cells forming colonies in the spleens of lethally irradiated mice (colony forming cells CFc) proliferates relatively slowly. After partial damage the population regenerates which is achieved by an increased proliferation rate. The effect of damage caused by different doses of hydroxyurea or vinblastine to the proliferation of the CFc was investigated. CFc population was measured in femur bone marrow after the grafting of a bone marrow sample into lethally irradiated mice recipients (spleen colony method). The proliferation rate was estimated either according to the magnitude of the fraction of cells synthesizing DNA in the S phase of the cell cycle, or according to the sensitivity of the population to repeated injections of vinblastine. Data showed that even after very minute damage by hydroxyurea the stem cells started to proliferate intensively. The effect was dose dependent. The comparable damage caused by vinblastine had a significantly weaker effect on the proliferation of the stem cells. It is concluded from the results that the proliferation response of the pluripotential stem cells depends on two factors: the extent of the damage caused to the hemopoietic tissue and the position of the killed cells in the cell cycle. (author)

  7. In vitro repopulation of haemopoietic stem cells after irradiation

    International Nuclear Information System (INIS)

    Mori, K.J.; Kumagai, Keiko; Seto, Akira; Ito, Yohei

    1981-01-01

    A culture system was designed in which proliferation of the haemopoietic stem cells was supported by adherent 'stromal' cell colonies. Application of the culture system to studies on kinetic behaviour of the haemopoietic stem cells after irradiation revealed; i) bone marrow stromal cells were radiosensitive with D 0 = 95R, when measured as the capability to proliferate and form adherent cell colonies in vitro, ii) radiosensitivity of the pluripotent stem cells (CFUs) in vitro was within the range of the in vivo sensitivity, iii) irradiated bone marrow cells under in vitro condition could repopulate at the same rate as those under in vivo condition, thereby suggesting that the function related to the support of haemopoiesis was radioresistant, iv) concentrations of both CFUs and granulocyte-macrophage precursor cells (CFUc) were higher in the irradiated cultures than those in unirradiated control culture at 3 weeks after irradiation. (author)

  8. Elimination of clonogenic tumor cells from HL-60, Daudi, and U-937 cell lines by laser photoradiation therapy: implications for autologous bone marrow purging

    International Nuclear Information System (INIS)

    Gulliya, K.S.; Pervaiz, S.

    1989-01-01

    Laser photoradiation therapy was tested in an in vitro model for its efficacy in the elimination of non-Hodgkin's lymphoma cells. Results show that at 31.2 J/cm2 of laser light in the presence of 20 micrograms/mL of merocyanine 540 (MC540) there was greater than 5 log reduction in Burkitt's lymphoma (Daudi) cells. Similar tumor cell kill was obtained for leukemia (HL-60) cells at a laser light dose of 93.6 J/cm2. However, to obtain the same efficiency of killing for histiocytic lymphoma (U-937) cells, a higher dose of MC540 (25 micrograms/mL) was required. Clonogenic tumor stem cell colony formation was reduced by greater than 5 logs after laser photoradiation therapy. Under identical conditions for each cell line the percent survival for granulocyte-macrophage colony-forming units (CFU-GM, 45.9%, 40%, 17.5%), granulocyte/erythroid/macrophage/megakaryocyte (GEMM, 40.1%, 20.1%, 11.5%), colony-forming units (CFU-C, 16.2%, 9.1%, 1.8%), and erythroid burst-forming units (BFU-E, 33.4%, 17.8%, 3.9%) was significantly higher than the tumor cells. Mixing of gamma ray-irradiated normal marrow cells with tumor cells (1:1 and 10:1 ratio) did not interfere with the elimination of tumor cells. The effect of highly purified recombinant interferon alpha (rIFN) on laser photoradiation therapy of tumor cells was also investigated. In the presence of rIFN (30 to 3,000 U/mL), the viability of leukemic cells was observed to increase from 0% to 1.5% with a concurrent decrease in membrane polarization, suggesting an increase in fluidity of cell membrane in response to rIFN. However, at higher doses of rIFN (6,000 to 12,000 U/mL) this phenomenon was not observed. The viability of lymphoma cells remained unaffected at all doses of rIFN tested

  9. Mammalian-enabled (MENA) protein enhances oncogenic potential and cancer stem cell-like phenotype in hepatocellular carcinoma cells.

    Science.gov (United States)

    Hu, Kunpeng; Huang, Pinzhu; Luo, Hui; Yao, Zhicheng; Wang, Qingliang; Xiong, Zhiyong; Lin, Jizong; Huang, He; Xu, Shilei; Zhang, Peng; Liu, Bo

    2017-08-01

    Mammalian-enabled (MENA) protein is an actin-regulatory protein that influences cell motility and adhesion. It is known to play a role in tumorigenicity of hepatocellular carcinoma (HCC) but the underlying molecular mechanism remains unknown. This study aimed to investigate the oncogenic potential of MENA and its capacity to regulate cancer stem cell (CSC)-like phenotypes in HCC cells. Real-time-PCR and western blot were used to assess mRNA and protein levels of target genes in human HCC tissue specimens and HCC cell lines, respectively. Stable MENA-overexpressing HCC cells were generated from HCC cell lines. Transwell cell migration and colony formation assays were employed to evaluate tumorigenicity. Ectopic expression of MENA significantly enhanced cell migration and colony-forming ability in HCC cells. Overexpression of MENA upregulated several hepatic progenitor/stem cell markers in HCC cells. A high MENA protein level was associated with high mRNA levels of MENA, CD133, cytokeratin 19 (CK19), and epithelial cell adhesion molecule (EpCAM) in human HCC tissues. Overexpression of MENA enhanced epithelial-to-mesenchymal transition (EMT) markers, extracellular signal-regulated kinases (ERK) phosphorylation, and the level of β-catenin in HCC cells. This study demonstrated that overexpression of MENA in HCC cells promoted stem cell markers, EMT markers, and tumorigenicity. These effects may involve, at least partially, the ERK and β-catenin signaling pathways.

  10. The effect of resveratrol in combination with irradiation and chemotherapy. Study using Merkel cell carcinoma cell lines

    International Nuclear Information System (INIS)

    Heiduschka, G.; Lill, C.; Brunner, M.; Thurnher, D.; Seemann, R.; Schmid, R.; Houben, R.; Bigenzahn, J.

    2014-01-01

    Merkel cell carcinoma (MCC) is a rare, but highly malignant tumor of the skin. In case of systemic disease, possible therapeutic options include irradiation or chemotherapy. The aim of this study was to evaluate whether the flavonoid resveratrol enhances the effect of radiotherapy or chemotherapy in MCC cell lines. The two MCC cell lines MCC13 and MCC26 were treated with increasing doses of resveratrol. Combination experiments were conducted with cisplatin and etoposide. Colony forming assays were performed after sequential irradiation with 1, 2, 3, 4, 6, and 8 Gy and apoptosis was assessed with flow cytometry. Expression of cancer drug targets was analyzed by real-time PCR array. Resveratrol is cytotoxic in MCC cell lines. Cell growth is inhibited by induction of apoptosis. The combination with cisplatin and etoposide resulted in a partially synergistic inhibition of cell proliferation. Resveratrol and irradiation led to a synergistic reduction in colony formation compared to irradiation alone. Evaluation of gene expression did not show significant difference between the cell lines. Due to its radiosensitizing effect, resveratrol seems to be a promising agent in combination with radiation therapy. The amount of chemosensitizing depends on the cell lines tested. (orig.) [de

  11. Cytokinetics and Regulation of Progenitor Cells

    Energy Technology Data Exchange (ETDEWEB)

    Lajtha, L. G. [Paterson Laboratories, Christie Hospital and Holt Radium Institute, Manchester (United Kingdom)

    1967-07-15

    Full text: In spite of great differences in the life-span of fully differentiated haemic cells, the cellular kinetics of their production appears to be similar. Recent evidence indicates a common ultimate stem cell for most of the cells in the peripheral blood. The various pathways of differentiation, however, result in transient dividing and differentiating cell populations which differ from each other not only in their specific biochemical processes but also in the manner of control and kinetic pattern of their proliferation. The population best understood is the erythroid progenitor series of cells, primarily because it has the greatest number of experimentally measurable parameters at the present. This will be discussed in detail and comparisons will be made with the myeloid and lymphoid progenitor populations. The fine structure of the bone-marrow stem cell population will be examined in particular, with regard to the suitability or otherwise of the current stem cell models to explain the kinetic pattern of all the peripheral blood elements after perturbations of their steady-state values. Four different assay methods of bone-marrow stem cells have been examined with regard to the kinetic pattern following perturbation of the steady-state system, e.g. by irradiation. Basically, the stem cell assays fall into two categories: those depending on grafting haemopoietic cells into suitably treated recipients, and those in which recovery of the population is allowed in the animal in which the perturbation was produced, without handling the cells. Evidence is accumulating which indicates that in the grafting techniques, a selective loss of stem cells may occur, . especially stem cells in cell cycle, hence in early stages of recovery of the population unduly low numerical values might be noted. In view of this observation, the concept of the colony-forming cell may have to be revised and instead the colony-forming property of the stem cell introduced. (author)

  12. Cytokinetics and Regulation of Progenitor Cells

    International Nuclear Information System (INIS)

    Lajtha, L.G.

    1967-01-01

    Full text: In spite of great differences in the life-span of fully differentiated haemic cells, the cellular kinetics of their production appears to be similar. Recent evidence indicates a common ultimate stem cell for most of the cells in the peripheral blood. The various pathways of differentiation, however, result in transient dividing and differentiating cell populations which differ from each other not only in their specific biochemical processes but also in the manner of control and kinetic pattern of their proliferation. The population best understood is the erythroid progenitor series of cells, primarily because it has the greatest number of experimentally measurable parameters at the present. This will be discussed in detail and comparisons will be made with the myeloid and lymphoid progenitor populations. The fine structure of the bone-marrow stem cell population will be examined in particular, with regard to the suitability or otherwise of the current stem cell models to explain the kinetic pattern of all the peripheral blood elements after perturbations of their steady-state values. Four different assay methods of bone-marrow stem cells have been examined with regard to the kinetic pattern following perturbation of the steady-state system, e.g. by irradiation. Basically, the stem cell assays fall into two categories: those depending on grafting haemopoietic cells into suitably treated recipients, and those in which recovery of the population is allowed in the animal in which the perturbation was produced, without handling the cells. Evidence is accumulating which indicates that in the grafting techniques, a selective loss of stem cells may occur, . especially stem cells in cell cycle, hence in early stages of recovery of the population unduly low numerical values might be noted. In view of this observation, the concept of the colony-forming cell may have to be revised and instead the colony-forming property of the stem cell introduced. (author)

  13. Oxygen concentration inside a functioning photosynthetic cell.

    Science.gov (United States)

    Kihara, Shigeharu; Hartzler, Daniel A; Savikhin, Sergei

    2014-05-06

    The excess oxygen concentration in the photosynthetic membranes of functioning oxygenic photosynthetic cells was estimated using classical diffusion theory combined with experimental data on oxygen production rates of cyanobacterial cells. The excess oxygen concentration within the plesiomorphic cyanobacterium Gloeobactor violaceus is only 0.025 μM, or four orders of magnitude lower than the oxygen concentration in air-saturated water. Such a low concentration suggests that the first oxygenic photosynthetic bacteria in solitary form could have evolved ∼2.8 billion years ago without special mechanisms to protect them against reactive oxygen species. These mechanisms instead could have been developed during the following ∼500 million years while the oxygen level in the Earth's atmosphere was slowly rising. Excess oxygen concentrations within individual cells of the apomorphic cyanobacteria Synechocystis and Synechococcus are 0.064 and 0.25 μM, respectively. These numbers suggest that intramembrane and intracellular proteins in isolated oxygenic photosynthetic cells are not subjected to excessively high oxygen levels. The situation is different for closely packed colonies of photosynthetic cells. Calculations show that the excess concentration within colonies that are ∼40 μm or larger in diameter can be comparable to the oxygen concentration in air-saturated water, suggesting that species forming colonies require protection against reactive oxygen species even in the absence of oxygen in the surrounding atmosphere. Copyright © 2014 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  14. Accumulated lipids rather than the rigid cell walls impede the extraction of genetic materials for effective colony PCRs in Chlorella vulgaris

    Science.gov (United States)

    2013-01-01

    Background Failure of colony PCRs in green microalga Chlorella vulgaris is typically attributed to the difficulty in disrupting its notoriously rigid cell walls for releasing the genetic materials and therefore the development of an effective colony PCR procedure in C. vulgaris presents a challenge. Results Here we identified that colony PCR results were significantly affected by the accumulated lipids rather than the rigid cell walls of C. vulgaris. The higher lipids accumulated in C. vulgaris negatively affects the effective amplification by DNA polymerase. Based on these findings, we established a simple and extremely effective colony PCR procedure in C. vulgaris. By simply pipetting/votexing the pellets of C. vulgaris in 10 ul of either TE (10 mM Tris/1 mM EDTA) or 0.2% SDS buffer at room temperature, followed by the addition of 10 ul of either hexane or Phenol:Chloroform:Isoamyl Alcohol in the same PCR tube for extraction. The resulting aqueous phase was readily PCR-amplified as genomic DNA templates as demonstrated by successful amplification of the nuclear 18S rRNA and the chloroplast rbcL gene. This colony PCR protocol is effective and robust in C. vulgaris and also demonstrates its effectiveness in other Chlorella species. Conclusions The accumulated lipids rather than the rigid cell walls of C. vulgaris significantly impede the extraction of genetic materials and subsequently the effective colony PCRs. The finding has the potential to aid the isolation of high-quality total RNAs and mRNAs for transcriptomic studies in addition to the genomic DNA isolation in Chlorella. PMID:24219401

  15. Ant Colony Optimization Algorithm for Centralized Dynamic Channel Allocation in Multi-Cell OFDMA Systems

    Science.gov (United States)

    Kim, Hyo-Su; Kim, Dong-Hoi

    The dynamic channel allocation (DCA) scheme in multi-cell systems causes serious inter-cell interference (ICI) problem to some existing calls when channels for new calls are allocated. Such a problem can be addressed by advanced centralized DCA design that is able to minimize ICI. Thus, in this paper, a centralized DCA is developed for the downlink of multi-cell orthogonal frequency division multiple access (OFDMA) systems with full spectral reuse. However, in practice, as the search space of channel assignment for centralized DCA scheme in multi-cell systems grows exponentially with the increase of the number of required calls, channels, and cells, it becomes an NP-hard problem and is currently too complicated to find an optimum channel allocation. In this paper, we propose an ant colony optimization (ACO) based DCA scheme using a low-complexity ACO algorithm which is a kind of heuristic algorithm in order to solve the aforementioned problem. Simulation results demonstrate significant performance improvements compared to the existing schemes in terms of the grade of service (GoS) performance and the forced termination probability of existing calls without degrading the system performance of the average throughput.

  16. RECOMBINANT HUMAN MAST-CELL GROWTH-FACTOR SUPPORTS ERYTHROID COLONY FORMATION IN POLYCYTHEMIA-VERA IN THE PRESENCE AND ABSENCE OF ERYTHROPOIETIN AND SERUM

    NARCIS (Netherlands)

    MULLER, EW; DEWOLF, JTM; HENDRIKS, DW; ESSELINK, MT; HALIE, MR; VELLENGA, E

    The effect of mast cell growth factor (MGF) was studied on erythropoietin (Epo)-dependent and Epo-independent (''spontaneous'') erythroid colony formation in patients with polycythemia vera (PV). MGF stimulated both Epo-dependent and Epo-independent erythroid colony formation from PV peripheral

  17. Effect of cell-phone radiofrequency on angiogenesis and cell invasion in human head and neck cancer cells.

    Science.gov (United States)

    Alahmad, Yaman M; Aljaber, Mohammed; Saleh, Alaaeldin I; Yalcin, Huseyin C; Aboulkassim, Tahar; Yasmeen, Amber; Batist, Gerald; Moustafa, Ala-Eddin Al

    2018-05-13

    Today, the cell phone is the most widespread technology globally. However, the outcome of cell-phone radiofrequency on head and neck cancer progression has not yet been explored. The chorioallantoic membrane (CAM) and human head and neck cancer cell lines, FaDu and SCC25, were used to explore the outcome of cell-phone radiofrequency on angiogenesis, cell invasion, and colony formation of head and neck cancer cells, respectively. Western blot analysis was used to investigate the impact of the cell phone on the regulation of E-cadherin and Erk1/Erk2 genes. Our data revealed that cell-phone radiofrequency promotes angiogenesis of the CAM. In addition, the cell phone enhances cell invasion and colony formation of human head and neck cancer cells; this is accompanied by a downregulation of E-cadherin expression. More significantly, we found that the cell phone can activate Erk1/Erk2 in our experimental models. Our investigation reveals that cell-phone radiofrequency could enhance head and neck cancer by stimulating angiogenesis and cell invasion via Erk1/Erk2 activation. © 2018 Wiley Periodicals, Inc.

  18. Endothelial progenitor cell subsets and preeclampsia: Findings and controversies

    Directory of Open Access Journals (Sweden)

    Armin Attar

    2017-10-01

    Full Text Available Vascular remodeling is an essential component of gestation. Endothelial progenitor cells (EPCs play an important role in the regulation of vascular homeostasis. The results of studies measuring the number of EPCs in normal pregnancies and in preeclampsia have been highly controversial or even contradictory because of some variations in technical issues and different methodologies enumerating three distinct subsets of EPCs: circulating angiogenic cells (CAC, colony forming unit endothelial cells (CFU-ECs, and endothelial colony-forming cells (ECFCs. In general, most studies have shown an increase in the number of CACs in the maternal circulation with a progression in the gestational age in normal pregnancies, while functional capacities measured by CFU-ECs and ECFCs remain intact. In the case of preeclampsia, mobilization of CACs and ECFCs occurs in the peripheral blood of pregnant women, but the functional capacities shown by culture of the derived colony-forming assays (CFU-EC and ECFC assays are altered. Furthermore, the number of all EPC subsets will be reduced in umbilical cord blood in the case of preeclampsia. As EPCs play an important role in the homeostasis of vascular networks, the difference in their frequency and functionality in normal pregnancies and those with preeclampsia can be expected. In this review, there was an attempt to provide a justification for these controversies.

  19. Importance of Sox2 in maintenance of cell proliferation and multipotency of mesenchymal stem cells in low-density culture.

    Science.gov (United States)

    Yoon, D S; Kim, Y H; Jung, H S; Paik, S; Lee, J W

    2011-10-01

    This study has aimed to repopulate 'primitive' cells from late-passage mesenchymal stem cells (MSCs) of poor multipotentiality and low cell proliferation rate, by simply altering plating density. Effects of low density culture compared t high density culture on late-passage bone marrow (BM)-derived MSCs and pluripotency markers of multipotentiality were investigated. Cell proliferation, gene expression, RNA interference and differentiation potential were assayed. We repopulated 'primitive' cells by replating late-passage MSCs at low density (17 cells/cm(2) ) regardless of donor age. Repopulated MSCs from low-density culture were smaller cells with spindle shaped morphology compared to MSCs from high-density culture. The latter had enhanced colony-forming ability, proliferation rate, and adipogenic and chondrogenic potential. Strong expression of osteogenic-related genes (Cbfa1, Dlx5, alkaline phosphatase and type Ι collagen) in late-passage MSCs was reduced by replating at low density, whereas expression of three pluripotency markers (Sox2, Nanog and Oct-4), Osterix and Msx2 reverted to levels of early-passage MSCs. Knockdown of Sox2 and Msx2 but not Nanog, using RNA interference, showed significant decrease in colony-forming ability. Specifically, knockdown of Sox2 significantly inhibited multipotentiality and cell proliferation. Our data suggest that plating density should be considered to be a critical factor for enrichment of 'primitive' cells from heterogeneous BM and that replicative senescence and multipotentiality of MSCs during in vitro expansion may be predominantly regulated through Sox2. © 2011 Blackwell Publishing Ltd.

  20. Novel method for isolation of murine clara cell secretory protein-expressing cells with traces of stemness.

    Directory of Open Access Journals (Sweden)

    Xiao-Yang Wang

    Full Text Available Clara cells are non-ciliated, secretory bronchiolar epithelial cells that serve to detoxify harmful inhaled substances. Clara cells also function as stem/progenitor cells for repair in the bronchioles. Clara cell secretory protein (CCSP is specifically expressed in pulmonary Clara cells and is widely used as a Clara cell marker. In addition CCSP promoter is commonly used to direct gene expression into the lung in transgenic models. The discovery of CCSP immunoreactivity in plasma membranes of airway lining cells prompted us to explore the possibility of enriching Clara cells by flow cytometry. We established a novel and simple method for the isolation of CCSP-expressing cell Clara cells using a combination of mechanical and enzymatic dissociation followed by flow cytometry sorting technology. We showed that ∼25% of dissociated cells from whole lung expressed CCSP. In the resulting preparation, up to 98% of cells expressed CCSP. Notably, we found that several common stem cell markers including CD44, CD133, Sca-1 and Sox2 were expressed in CCSP(+ cells. Moreover, CCSP(+ cells were able to form spheroid colonies in vitro with 0.97‰ efficiency. Parallel studies in vivo confirmed that a small population of CCSP(-expressing cells in mouse airways also demonstrates stem cell-like properties such as label retention and harboring rare bronchioalveolar stem cells (BASCs in terminal bronchioles (TBs. We conclude that CCSP(+ cells exhibit a number of stem cell-like features including stem cell marker expression, bronchosphere colony formation and self-renewal ability. Clara cell isolation by flow cytometry sorting is a useful method for investigating the function of primary Clara cells in stem cell research and mouse models.

  1. Capacity of ultraviolet-induced DNA repair in human glioma cells

    Energy Technology Data Exchange (ETDEWEB)

    Itoh, Hiroji

    1987-04-01

    A DNA repair abnormality is likely related to an increased incidence of neoplasms in several autosomal recessive diseases such as xeroderma pigmentosum, Fanconi's anemia, Bloom's syndrome and ataxia telangiectasia. In human glioma cells, however, there are only a few reports on DNA repair. In this study, an ultraviolet (UV)-induced DNA repair was examined systematically in many human glioma cells. Two human malignant glioma cell lines (MMG-851, U-251-MG) and 7 human glioma cell strains (4, benign; 3, malignant) of short term culture, in which glial fibrillary acidic protein (GFAP) staining were positive, were used. To investigate the capacity of DNA repair, UV sensitivity was determined by colony formation; excision repair by autoradiography and Cytosine Arabinoside (Ara-C) assay; and post-replication repair by the joining rate of newly synthesized DNA. As a result, the colony-forming abilities of malignant glioma cell lines were lower than those of normal human fibroblasts, but no difference was found between two malignant glioma cell lines. The excision repair of the malignant group (2 cell lines and 3 cell strains) was apparently lower than that of the benign group (4 cell strains). In two malignant glioma cell lines, the excision repair of MMG-851 was lower than that of U-251-MG, and the post-replication repair of MMG-851 was higher than that of U-251-MG. These results were considered to correspond well with colony-forming ability. The results indicate that there are some differences in each human malignant glioma cell in its UV-induced DNA repair mechanism, and that the excision repair of the malignant glioma cells is apparently lower than that of the benign glioma cells. These findings may be useful for diagnosis and treatment.

  2. X-ray-induced in vitro neoplastic transformation of human diploid cells

    International Nuclear Information System (INIS)

    Borek, C.

    1980-01-01

    The neoplastic transformation, in vitro, of human diploid cells by x-ray irradiation into cells which can progress, in vitro, into advanced stages of neoplastic development is described. The cells are shown to form colonies in agar and to give rise to tumours when injected into nude mice. (U.K.)

  3. Detection and quantification of intracellular bacterial colonies by automated, high-throughput microscopy.

    Science.gov (United States)

    Ernstsen, Christina L; Login, Frédéric H; Jensen, Helene H; Nørregaard, Rikke; Møller-Jensen, Jakob; Nejsum, Lene N

    2017-08-01

    To target bacterial pathogens that invade and proliferate inside host cells, it is necessary to design intervention strategies directed against bacterial attachment, cellular invasion and intracellular proliferation. We present an automated microscopy-based, fast, high-throughput method for analyzing size and number of intracellular bacterial colonies in infected tissue culture cells. Cells are seeded in 48-well plates and infected with a GFP-expressing bacterial pathogen. Following gentamicin treatment to remove extracellular pathogens, cells are fixed and cell nuclei stained. This is followed by automated microscopy and subsequent semi-automated spot detection to determine the number of intracellular bacterial colonies, their size distribution, and the average number per host cell. Multiple 48-well plates can be processed sequentially and the procedure can be completed in one working day. As a model we quantified intracellular bacterial colonies formed by uropathogenic Escherichia coli (UPEC) during infection of human kidney cells (HKC-8). Urinary tract infections caused by UPEC are among the most common bacterial infectious diseases in humans. UPEC can colonize tissues of the urinary tract and is responsible for acute, chronic, and recurrent infections. In the bladder, UPEC can form intracellular quiescent reservoirs, thought to be responsible for recurrent infections. In the kidney, UPEC can colonize renal epithelial cells and pass to the blood stream, either via epithelial cell disruption or transcellular passage, to cause sepsis. Intracellular colonies are known to be clonal, originating from single invading UPEC. In our experimental setup, we found UPEC CFT073 intracellular bacterial colonies to be heterogeneous in size and present in nearly one third of the HKC-8 cells. This high-throughput experimental format substantially reduces experimental time and enables fast screening of the intracellular bacterial load and cellular distribution of multiple

  4. RNA interference-mediated silencing of speckle-type POZ protein promotes apoptosis of renal cell cancer cells

    Directory of Open Access Journals (Sweden)

    Liu X

    2016-04-01

    Full Text Available Xiaoxia Liu, Guiling Sun, Xiuju Sun Department of Nephrology, Affiliated Hospital of Weifang Medical University, Weifang, People’s Republic of China Abstract: This study aimed to investigate the effects of silencing the speckle-type POZ protein (SPOP gene on renal cell cancer (RCC cells and to explore its possible mechanism. The A498 and ACHN RCC cells were transfected with small interference RNA (siRNA-SPOP by lipofection methods. The silencing efficiency was monitored by quantitative real-time polymerase chain reaction and Western blot. The effects of SPOP silencing on cell apoptosis, cell viability, colony formation ability, cell migration ability, and chemosensitivity to Sorafenib were assessed by flow cytometry, an MTT assay, a colony formation assay, a trans-well migration assay, and a CCK-8 assay, respectively. Its effects on the expression of several cytokines were determined by a protein microarray. Relevant signaling pathways were also analyzed. Compared with the control group, the cell apoptosis rate was significantly higher; the cell viability, the colony formation, and migration ability were significantly decreased in the siRNA-SPOP group. The protein microarray screening showed that the expression of vascular endothelial growth factor receptor, matrix metallopeptidase-9, vascular cell adhesion molecule-1, and stromal cell-derived factor-1 in the siRNA group was significantly decreased and that the expression of granulocyte–macrophage colony-stimulating factor and E-cadherin was significantly increased (P<0.05. The relevant signaling pathways were the integrin-mediated cell surface interactions pathway and extracellular matrix organization signal pathway. SPOP gene silencing induced cell apoptosis, decreased cell viability, colony formation, and migration ability, and elevated the drug sensitivity in the RCC cells. A possible mechanism is that silencing SPOP induces the differential expression of E-cadherin, vascular endothelial

  5. Implementation of the Bee Colony Optimization method for the design of fuel cells; Implementacion del metodo Bee Colony Optimization para el diseno de celdas de combustible

    Energy Technology Data Exchange (ETDEWEB)

    Esquivel E, J.; Ortiz S, J. J., E-mail: jaime.esquivel@fi.uaemex.mx [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2011-11-15

    The present work shows the results obtained after applying the Bee Colony Optimization algorithm in the design of fuel cells for a BWR. The algorithm that is implemented, works following the behavior that have the bees when pollinating a flowers field. The bees carry out an exhaustive analysis in the cell, so they leave generating diverse configurations where different fuel bars are placed with different uranium enrichments to reach a value mean, with a specific number of gadolinium bars. The behavior of the generated cell is evaluated by means of the use of the commercial code CASMO-4, which shows the variables that allow fixing if the cell fulfills the requirements. Such variables are the local potential peak factor and the neutrons multiplication factor in an infinite medium. (Author)

  6. Differential effect of procaine on irradiated mammalian cells in culture

    International Nuclear Information System (INIS)

    Djordjevic, B.

    1979-01-01

    HeLa and V-79 Chinese hamster cells temporarily stored in ampoules were treated with the local anesthetic procaine. Postirradiation treatment increased lethality in HeLa cells depending on drug concentration, duration of treatment, and cell density, as measured by colony-forming ability upon plating. If present during irradiation only, procaine protected from irradiation. In V-79 cells, procaine potentiated radiation lethality only in freshly trypsinized cells. Procaine effect was thus cell type specific and most likely involved the cell membrane

  7. Radiosensitivity of four human tumor xenografts. Influence of hypoxia and cell-cell contact

    International Nuclear Information System (INIS)

    Guichard, M.; Dertinger, H.; Malaise, E.P.

    1983-01-01

    Contact effect (CE) and hypoxia have been studied in human tumor cell lines transplanted in athymic nude mice. Four cell lines - one melanoma (Bell) and three colorectal adenocarcinomas (HT29, HRT18, and HCT8) - were studied. Cell survival was determined with an in vivo in vitro colony-forming assay. Survival curves were obtained under three different conditions: (1) tumor cells irradiated in air-breathing mice, (2) tumor cells irradiated in animals asphyxiated for 10 min, and (3) tumor cells plated and irradiated either immediately or 5 hr later. For all cell lines, radiosensitivity appeared to be lower when cells were irradiated in vivo than when they were irradiated in vitro. Only in the case of the HCT8 tumor did the relative in vivo radioresistance seem to be linked to hypoxia; in the other cell lines, hypoxia alone could not account for the lower in vivo radiosensitivity. Our results suggest that a CE plays an important role in the response of human xenografts to irradiation

  8. RNA interference-mediated silencing of speckle-type POZ protein promotes apoptosis of renal cell cancer cells.

    Science.gov (United States)

    Liu, Xiaoxia; Sun, Guiling; Sun, Xiuju

    2016-01-01

    This study aimed to investigate the effects of silencing the speckle-type POZ protein (SPOP) gene on renal cell cancer (RCC) cells and to explore its possible mechanism. The A498 and ACHN RCC cells were transfected with small interference RNA (siRNA)-SPOP by lipofection methods. The silencing efficiency was monitored by quantitative real-time polymerase chain reaction and Western blot. The effects of SPOP silencing on cell apoptosis, cell viability, colony formation ability, cell migration ability, and chemosensitivity to Sorafenib were assessed by flow cytometry, an MTT assay, a colony formation assay, a trans-well migration assay, and a CCK-8 assay, respectively. Its effects on the expression of several cytokines were determined by a protein microarray. Relevant signaling pathways were also analyzed. Compared with the control group, the cell apoptosis rate was significantly higher; the cell viability, the colony formation, and migration ability were significantly decreased in the siRNA-SPOP group. The protein microarray screening showed that the expression of vascular endothelial growth factor receptor, matrix metallopeptidase-9, vascular cell adhesion molecule-1, and stromal cell-derived factor-1 in the siRNA group was significantly decreased and that the expression of granulocyte-macrophage colony-stimulating factor and E-cadherin was significantly increased (Pmatrix organization signal pathway. SPOP gene silencing induced cell apoptosis, decreased cell viability, colony formation, and migration ability, and elevated the drug sensitivity in the RCC cells. A possible mechanism is that silencing SPOP induces the differential expression of E-cadherin, vascular endothelial growth factor receptor, matrix metallopeptidase-9, and vascular cell adhesion molecule, which are related to the integrin-mediated cell surface interactions and extracellular matrix organization signaling pathway.

  9. Feeder-cell-independent culture of the pig-embryonic-stem-cell-derived exocrine pancreatic cell line, PICM-31

    Science.gov (United States)

    The adaptation to feeder-independent growth of a pig embryonic stem cell-derived pancreatic cell line is described. The parental PICM-31 cell line, previously characterized as an exocrine pancreas cell line, was colony-cloned two times in succession resulting in the subclonal cell line, PICM-31A1. P...

  10. High level of expression of recombinant human granulocyte-macrophage colony stimulating factor in transgenic rice cell suspension culture

    DEFF Research Database (Denmark)

    Shin, Yun-Ji; Hong, Shin-Young; Kwon, Tae-Ho

    2003-01-01

    Recombinant human granulocyte-macrophage colony stimulating factor (hGM-CSF) has been previously produced in tobacco cell suspension cultures. However, the amount of hGM-CSF accumulated in the culture medium dropped quickly from its maximum of 150 microg/L at 5 d after incubation. To overcome...... of recombinant hGM-CSF in transgenic rice cell suspension culture and protease activity of this culture medium was low compared to that of tobacco culture system....

  11. Buckling instability in ordered bacterial colonies

    Science.gov (United States)

    Boyer, Denis; Mather, William; Mondragón-Palomino, Octavio; Orozco-Fuentes, Sirio; Danino, Tal; Hasty, Jeff; Tsimring, Lev S.

    2011-04-01

    Bacterial colonies often exhibit complex spatio-temporal organization. This collective behavior is affected by a multitude of factors ranging from the properties of individual cells (shape, motility, membrane structure) to chemotaxis and other means of cell-cell communication. One of the important but often overlooked mechanisms of spatio-temporal organization is direct mechanical contact among cells in dense colonies such as biofilms. While in natural habitats all these different mechanisms and factors act in concert, one can use laboratory cell cultures to study certain mechanisms in isolation. Recent work demonstrated that growth and ensuing expansion flow of rod-like bacteria Escherichia coli in confined environments leads to orientation of cells along the flow direction and thus to ordering of cells. However, the cell orientational ordering remained imperfect. In this paper we study one mechanism responsible for the persistence of disorder in growing cell populations. We demonstrate experimentally that a growing colony of nematically ordered cells is prone to the buckling instability. Our theoretical analysis and discrete-element simulations suggest that the nature of this instability is related to the anisotropy of the stress tensor in the ordered cell colony.

  12. Neutrophil-induced transmigration of tumour cells treated with tumour-conditioned medium is facilitated by granulocyte-macrophage colony-stimulating factor.

    LENUS (Irish Health Repository)

    Wu, Q D

    2012-02-03

    OBJECTIVE: To investigate the effect of different cytokines that are present in tumour-conditioned medium on human neutrophil (PMN)-induced tumour cell transmigration. DESIGN: Laboratory study. SETTING: University hospital, Ireland. MATERIAL: Isolated human PMN and cultured human breast tumour cell line, MDA-MB-231. Interventions: Human PMN treated with either tumour-conditioned medium or different media neutralised with monoclonal antibodies (MoAb), and MDA-MB-231 cells were plated on macrovascular and microvascular endothelial monolayers in collagen-coated transwells to assess migration of tumour cells. MAIN OUTCOME MEASURES: Cytokines present in tumour-conditioned medium, PMN cytocidal function and receptor expression, and tumour cell transmigration. RESULTS: tumour-conditioned medium contained high concentrations of granulocyte-macrophage colony-stimulating factor (GM-CSF), vascular endothelial growth factor (VEGF), and interleukin 8 (IL-8), but not granulocyte colony-stimulating factor (G-CSF) and interleukin 3 (IL-3). Anti-GM-CSF MoAb significantly reduced PMN-induced transmigration of tumour cells treated with tumour-conditioned medium (p < 0.05), whereas anti-VEGF and anti-IL-8 MoAbs did not affect their migration. In addition, anti-GM-CSF MoAb, but not anti-VEGF or anti-IL-8 MoAb, reduced PMN CD11b and CD18 overexpression induced by tumour-conditioned medium (p < 0.05). CONCLUSION: These results indicate that the GM-CSF that is present in tumour-conditioned medium may be involved, at least in part, in alterations in PMN function mediated by the medium and subsequently PMN-induced transmigration of tumour cells.

  13. Autoradiographic assay of mutants resistant to diphtheria toxin in mammalian cells in vitro

    International Nuclear Information System (INIS)

    Ronen, A.; Gingerich, J.D.; Duncan, A.M.V.; Heddle, J.A.

    1984-01-01

    Diptheria toxin kills mammalian cells by ribosylating elongation factor 2, a protein factor necessary for protein synthesis. The frequency of cells able to form colonies in the presence of the toxin can be used as an assay for mutation to diphtheria toxin resistance. Resistance to diphtheria toxin can also be detected autoradiographically in cells exposed to [ 3 H]leucine after treatment with the toxin. In cultures of Chinese hamster ovary cells, the frequency of such resistant cells is increased by exposure of the cells to γ-rays, ultraviolet light, ethylnitrosourea, mitomycin c, ethidium bromide, and 5-bromo-2'-deoxyuridine in a dose- and time-dependent manner. The resistant cells form discrete microcolonies if they are allowed to divide several times before intoxication which indicates that they are genuine mutants. The assay is potentially adaptable to any cell population that can be intoxicated with diphtheria toxin and labeled with [ 3 H]leucine, whether or not the cells can form colonies. It may be useful, therefore, for measuring mutation rates in slowly growing or nondividing cell populations such as breast, brain, and liver, as well as in cells that do divide but cannot be readily cloned, such as the colonic epithelium. 23 references, 6 figures

  14. Isolation of sphere-forming stem cells from the mouse inner ear.

    Science.gov (United States)

    Oshima, Kazuo; Senn, Pascal; Heller, Stefan

    2009-01-01

    The mammalian inner ear has very limited ability to regenerate lost sensory hair cells. This deficiency becomes apparent when hair cell loss leads to hearing loss as a result of either ototoxic insult or the aging process. Coincidently, with this inability to regenerate lost hair cells, the adult cochlea does not appear to harbor cells with a proliferative capacity that could serve as progenitor cells for lost cells. In contrast, adult mammalian vestibular sensory epithelia display a limited ability for hair cell regeneration, and sphere-forming cells with stem cell features can be isolated from the adult murine vestibular system. The neonatal inner ear, however, does harbor sphere-forming stem cells residing in cochlear and vestibular tissues. Here, we provide protocols to isolate sphere-forming stem cells from neonatal vestibular and cochlear sensory epithelia as well as from the spiral ganglion. We further describe procedures for sphere propagation, cell differentiation, and characterization of inner ear cell types derived from spheres. Sphere-forming stem cells from the mouse inner ear are an important tool for the development of cellular replacement strategies of damaged inner ears and are a bona fide progenitor cell source for transplantation studies.

  15. Spontaneous emergence of large-scale cell cycle synchronization in amoeba colonies

    International Nuclear Information System (INIS)

    Segota, Igor; Boulet, Laurent; Franck, David; Franck, Carl

    2014-01-01

    Unicellular eukaryotic amoebae Dictyostelium discoideum are generally believed to grow in their vegetative state as single cells until starvation, when their collective aspect emerges and they differentiate to form a multicellular slime mold. While major efforts continue to be aimed at their starvation-induced social aspect, our understanding of population dynamics and cell cycle in the vegetative growth phase has remained incomplete. Here we show that cell populations grown on a substrate spontaneously synchronize their cell cycles within several hours. These collective population-wide cell cycle oscillations span millimeter length scales and can be completely suppressed by washing away putative cell-secreted signals, implying signaling by means of a diffusible growth factor or mitogen. These observations give strong evidence for collective proliferation behavior in the vegetative state. (paper)

  16. Buckling instability in ordered bacterial colonies

    International Nuclear Information System (INIS)

    Boyer, Denis; Mather, William; Mondragón-Palomino, Octavio; Danino, Tal; Hasty, Jeff; Orozco-Fuentes, Sirio; Tsimring, Lev S

    2011-01-01

    Bacterial colonies often exhibit complex spatio-temporal organization. This collective behavior is affected by a multitude of factors ranging from the properties of individual cells (shape, motility, membrane structure) to chemotaxis and other means of cell–cell communication. One of the important but often overlooked mechanisms of spatio-temporal organization is direct mechanical contact among cells in dense colonies such as biofilms. While in natural habitats all these different mechanisms and factors act in concert, one can use laboratory cell cultures to study certain mechanisms in isolation. Recent work demonstrated that growth and ensuing expansion flow of rod-like bacteria Escherichia coli in confined environments leads to orientation of cells along the flow direction and thus to ordering of cells. However, the cell orientational ordering remained imperfect. In this paper we study one mechanism responsible for the persistence of disorder in growing cell populations. We demonstrate experimentally that a growing colony of nematically ordered cells is prone to the buckling instability. Our theoretical analysis and discrete-element simulations suggest that the nature of this instability is related to the anisotropy of the stress tensor in the ordered cell colony

  17. Isolation and characterization of a radiosensitive Chinese hamster ovary cell line

    International Nuclear Information System (INIS)

    Fuller, L.F.

    1987-01-01

    A x-ray sensitive Chinese hamster ovary cell line was isolated using a semi-automated procedure in which mutagenized CHO cells were allowed to form colonies on top of agar, x-irradiated, then photographed at two later times. Comparison of the photographs allowed the identification of colonies which displayed significant growth arrest. One of the colonies identified in this manner produced a stable, radiosensitive line. This cell line is normal in x-ray induced inhibition of DNA synthesis, and single- and double-strand break repair, and is moderately sensitive to ethyl methane sulfonate and UV light. The sensitive line performs only half as much x-ray-induced repair replication as the parental line and this deficiency is believed to be the primary cause of its radiosensitivity. The sensitive line produces significantly higher numbers of x-ray-induced chromosome and chromatid aberrations including chromatid aberrations following exposure during the G 1 phase of the cell cycle. The line is hypomutable compared to the parental line with x-ray exposure inducing only one-third as many 6-thioguanine resistant colonies

  18. A full genomic characterization of the development of a stable Small Colony Variant cell-type by a clinical Staphylococcus aureus strain.

    Science.gov (United States)

    Bui, Long M G; Kidd, Stephen P

    2015-12-01

    A key to persistent and recurrent Staphylococcus aureus infections is its ability to adapt to diverse and toxic conditions. This ability includes a switch into a biofilm or to the quasi-dormant Small Colony Variant (SCV). The development and molecular attributes of SCVs have been difficult to study due to their rapid reversion to their parental cell-type. We recently described the unique induction of a matrix-embedded and stable SCV cell-type in a clinical S. aureus strain (WCH-SK2) by growing the cells with limiting conditions for a prolonged timeframe. Here we further study their characteristics. They possessed an increased viability in the presence of antibiotics compared to their non-SCV form. Their stability implied that there had been genetic changes; we therefore determined both the genome sequence of WCH-SK2 and its stable SCV form at a single base resolution, employing Single Molecular Real-Time (SMRT) sequencing that enabled the methylome to also be determined. The genetic features of WCH-SK2 have been identified; the SCCmec type, the pathogenicity and genetic islands and virulence factors. The genetic changes that had occurred in the stable SCV form were identified; most notably being in MgrA, a global regulator, and RsbU, a phosphoserine phosphatase within the regulatory pathway of the sigma factor SigB. There was a shift in the methylomes of the non-SCV and stable SCV forms. We have also shown a similar induction of this cell-type in other S. aureus strains and performed a genetic comparison to these and other S. aureus genomes. We additionally map RNAseq data to the WCH-SK2 genome in a transcriptomic analysis of the parental, SCV and stable SCV cells. The results from this study represent the unique identification of a suite of epigenetic, genetic and transcriptional factors that are implicated in the switch in S. aureus to its persistent SCV form. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Comparative Effects of Platelet-Rich Plasma, Platelet Lysate, and Fetal Calf Serum on Mesenchymal Stem Cells.

    Science.gov (United States)

    Lykov, A P; Bondarenko, N A; Surovtseva, M A; Kim, I I; Poveshchenko, O V; Pokushalov, E A; Konenkov, V I

    2017-10-01

    We studied the effects of human platelet-rich plasma and platelet lysate on proliferation, migration, and colony-forming properties of rat mesenchymal stem cells. Platelet-rich plasma and platelet lysate stimulated the proliferation, migration, and colony formation of mesenchymal stem cells. A real-time study showed that platelet-rich plasma produces the most potent stimulatory effect, while both platelet-rich plasma and platelet lysate stimulated migration of cells.

  20. The effect of thymus cells on bone marrow transplants into sublethally irradiated mice

    International Nuclear Information System (INIS)

    Kruszewski, J.A.; Szcylik, C.; Wiktor-Jedrzejczak, W.

    1984-01-01

    Bone marrow cells formed similar numbers of 10-days spleen colonies in sublethally (6 Gy) irradiated C57B1/6 mice as in lethally (7.5 Gy) irradiated mice i.e. approximately 20 per 10 5 cells. Numbers of 10 day endogenous spleen colonies in sublethally irradiated mice (0.2 to 0.6 per spleen) did not differ significantly from the numbers in lethally irradiated mice. Yet, transplants of 10 7 coisogenic marrow cells into sublethally irradiated mice resulted in predominantly endogenous recovery of granulocyte system as evidenced by utilization of ''beige'' marker for transplanted cells. Nevertheless, transplanted cells engrafted into sublethally irradiated mice were present in their hemopoietic tissues throughout the observation period of 2 months never exceeding 5 to 10% of cells. Thymus cells stimulated endogenous and exogenous spleen colony formation as well as endogenous granulopoietic recovery. Additionally, they increased both the frequency and absolute numbers of graft-derived granulocytic cells in hemopoietic organs of transplanted mice. They failed, however, to essentially change the quantitative relationships between endogenous and exogenous hemopoietic recovery. These results may suggest that spleen colony studies are not suitable for prediction of events following bone marrow transplant into sublethally irradiated mice. Simultaneously, they have strengthened the necessity for appropriate conditioning of recipients of marrow transplants. (orig.) [de

  1. Gonococcal attachment to eukaryotic cells

    International Nuclear Information System (INIS)

    James, J.F.; Lammel, C.J.; Draper, D.L.; Brown, D.A.; Sweet, R.L.; Brooks, G.F.

    1983-01-01

    The attachment of Neisseria gonorrhoeae to eukaryotic cells grown in tissue culture was analyzed by use of light and electron microscopy and by labeling of the bacteria with [ 3 H]- and [ 14 C]adenine. Isogenic piliated and nonpiliated N. gonorrhoeae from opaque and transparent colonies were studied. The results of light microscopy studies showed that the gonococci attached to cells of human origin, including Flow 2000, HeLa 229, and HEp 2. Studies using radiolabeled gonococci gave comparable results. Piliated N. gonorrhoeae usually attached in larger numbers than nonpiliated organisms, and those from opaque colonies attached more often than isogenic variants from transparent colonies. Day-to-day variation in rate of attachment was observed. Scanning electron microscopy studies showed the gonococcal attachment to be specific for microvilli of the host cells. It is concluded that more N. gonorrhoeae from opaque colonies, as compared with isogenic variants from transparent colonies, attach to eukaryotic cells grown in tissue culture

  2. Evidence for epithelial-mesenchymal transition in cancer stem-like cells derived from carcinoma cell lines of the cervix uteri.

    Science.gov (United States)

    Lin, Jiaying; Liu, Xishi; Ding, Ding

    2015-01-01

    The cancer stem cell (CSC) paradigm is one possible way to understand the genesis of cancer, and cervical cancer in particular. We quantified and enriched ALDH1(+) cells within cervical cancer cell lines and subsequently characterized their phenotypical and functional properties like invasion capacity and epithelial-mesenchymal transition (EMT). ALDH1 expression in spheroid-derived cells (SDC) and the parental monolayer-derived cell (MDC) line was compared by flow-cytometry. Invasion capability was evaluated by Matrigel assay and expression of EMT-related genes Twist 1, Twist 2, Snail 1, Snail 2, Vimentin and E-cadherin by real-time PCR. ALDH1 expression was significantly higher in SDC. ALDH1(+) cells showed increased colony-formation. SDC expressed lower levels of E-cadherin and elevated levels of Twist 1, Twist 2, Snail 1, Snail 2 and Vimentin compared to MDC. Cervical cancer cell lines harbor potential CSC, characterized by ALDH1 expression as well as properties like invasiveness, colony-forming ability, and EMT. CSC can be enriched by anchorage-independent culture techniques, which may be important for the investigation of their contribution to therapy resistance, tumor recurrence and metastasis.

  3. Bioactive form of resveratrol in glioblastoma cells and its safety for normal brain cells

    Directory of Open Access Journals (Sweden)

    Xiao-Hong Shu

    2013-05-01

    Full Text Available ABSTRACTBackground: Resveratrol, a plant polyphenol existing in grapes and many other natural foods, possesses a wide range of biological activities including cancer prevention. It has been recognized that resveratrol is intracellularly biotransformed to different metabolites, but no direct evidence has been available to ascertain its bioactive form because of the difficulty to maintain resveratrol unmetabolized in vivo or in vitro. It would be therefore worthwhile to elucidate the potential therapeutic implications of resveratrol metabolism using a reliable resveratrol-sensitive cancer cells.Objective: To identify the real biological form of trans-resveratrol and to evaluate the safety of the effective anticancer dose of resveratrol for the normal brain cells.Methods: The samples were prepared from the condition media and cell lysates of human glioblastoma U251 cells, and were purified by solid phase extraction (SPE. The samples were subjected to high performance liquid chromatography (HPLC and liquid chromatography/tandem mass spectrometry (LC/MS analysis. According to the metabolite(s, trans-resveratrol was biotransformed in vitro by the method described elsewhere, and the resulting solution was used to treat U251 cells. Meanwhile, the responses of U251 and primarily cultured rat normal brain cells (glial cells and neurons to 100μM trans-resveratrol were evaluated by multiple experimental methods.Results: The results revealed that resveratrol monosulfate was the major metabolite in U251 cells. About half fraction of resveratrol monosulfate was prepared in vitro and this trans-resveratrol and resveratrol monosulfate mixture showed little inhibitory effect on U251 cells. It is also found that rat primary brain cells (PBCs not only resist 100μM but also tolerate as high as 200μM resveratrol treatment.Conclusions: Our study thus demonstrated that trans-resveratrol was the bioactive form in glioblastoma cells and, therefore, the biotransforming

  4. Immune suppressor factor confers stromal cell line with enhanced supporting activity for hematopoietic stem cells

    International Nuclear Information System (INIS)

    Nakajima, Hideaki; Shibata, Fumi; Fukuchi, Yumi; Goto-Koshino, Yuko; Ito, Miyuki; Urano, Atsushi; Nakahata, Tatsutoshi; Aburatani, Hiroyuki; Kitamura, Toshio

    2006-01-01

    Immune suppressor factor (ISF) is a subunit of the vacuolar ATPase proton pump. We earlier identified a short form of ISF (ShIF) as a stroma-derived factor that supports cytokine-independent growth of mutant Ba/F3 cells. Here, we report that ISF/ShIF supports self-renewal and expansion of primary hematopoietic stem cells (HSCs). Co-culture of murine bone marrow cells with a stromal cell line overexpressing ISF or ShIF (MS10/ISF or MS10/ShIF) not only enhanced their colony-forming activity and the numbers of long-term culture initiating cells, but also maintained the competitive repopulating activity of HSC. This stem cell supporting activity depended on the proton-transfer function of ISF/ShIF. Gene expression analysis of ISF/ShIF-transfected cell lines revealed down-regulation of secreted frizzled-related protein-1 and tissue inhibitor of metalloproteinase-3, and the restoration of their expressions in MS10/ISF cells partially reversed its enhanced LTC-IC supporting activity to a normal level. These results suggest that ISF/ShIF confers stromal cells with enhanced supporting activities for HSCs by modulating Wnt-activity and the extracellular matrix

  5. Caffeine-enhanced survival of radiation-sensitive, repair-deficient Chinese hamster cells

    International Nuclear Information System (INIS)

    Utsumi, H.; Elkind, M.M.

    1983-01-01

    A clone of V79 Chinese hamster cells (V79-AL162/S-10) with unique properties has been isolated after a challenge of parental cells (V79-AL162) with 1 mM ouabain. Compared with parental cells, or with other clones isolated after the ouabain challenge, these cells form smaller colonies, are more sensitive to both x rays and fission-spectrum neutrons, and respond atypically to a postirradiation treatment with caffeine. Their enhanced response to x rays results mainly from a large reduction in the shoulder of their survival curve, probably because in late S phase, the most resistant phase in the cell cycle, the survival curve of these cells has a reduced shoulder width. Caffeine, and to a lesser extent theophylline, added to the colony-forming medium immediately after exposure appreciably increases the width of the shoulder of these sensitive cells, whereas caffeine has the opposite effect on the response of normal V79 cells. Thus the unique response of the V79-AL162/S-10 cells to a radiation posttreatment with caffeine (increased survival) results from a net increase in their ability to repair damage that is otherwise lethal; caffeine treatment ordinarly prevents normal V79 cells from repairing damage that is only potentially lethal

  6. Origins and Properties of Dental, Thymic, and Bone Marrow Mesenchymal Cells and Their Stem Cells

    Science.gov (United States)

    Komada, Yukiya; Yamane, Toshiyuki; Kadota, Daiji; Isono, Kana; Takakura, Nobuyuki; Hayashi, Shin-Ichi; Yamazaki, Hidetoshi

    2012-01-01

    Mesenchymal cells arise from the neural crest (NC) or mesoderm. However, it is difficult to distinguish NC-derived cells from mesoderm-derived cells. Using double-transgenic mouse systems encoding P0-Cre, Wnt1-Cre, Mesp1-Cre, and Rosa26EYFP, which enabled us to trace NC-derived or mesoderm-derived cells as YFP-expressing cells, we demonstrated for the first time that both NC-derived (P0- or Wnt1-labeled) and mesoderm-derived (Mesp1-labeled) cells contribute to the development of dental, thymic, and bone marrow (BM) mesenchyme from the fetal stage to the adult stage. Irrespective of the tissues involved, NC-derived and mesoderm-derived cells contributed mainly to perivascular cells and endothelial cells, respectively. Dental and thymic mesenchyme were composed of either NC-derived or mesoderm-derived cells, whereas half of the BM mesenchyme was composed of cells that were not derived from the NC or mesoderm. However, a colony-forming unit-fibroblast (CFU-F) assay indicated that CFU-Fs in the dental pulp, thymus, and BM were composed of NC-derived and mesoderm-derived cells. Secondary CFU-F assays were used to estimate the self-renewal potential, which showed that CFU-Fs in the teeth, thymus, and BM were entirely NC-derived cells, entirely mesoderm-derived cells, and mostly NC-derived cells, respectively. Colony formation was inhibited drastically by the addition of anti-platelet–derived growth factor receptor-β antibody, regardless of the tissue and its origin. Furthermore, dental mesenchyme expressed genes encoding critical hematopoietic factors, such as interleukin-7, stem cell factor, and cysteine-X-cysteine (CXC) chemokine ligand 12, which supports the differentiation of B lymphocytes and osteoclasts. Therefore, the mesenchymal stem cells found in these tissues had different origins, but similar properties in each organ. PMID:23185234

  7. Effect of histones on hematopoietic stem cells-precursor in normal and irradiated organism

    International Nuclear Information System (INIS)

    Semina, O.V.; Semenets, T.N.; Zeppezauer, M.; Cebecauer, L.; Poverenny, A.M.

    1994-01-01

    Radiotherapeutic activity of histone fractions H 1 and H 2A /H 2B were studied. It was demonstrated that both fractions are able to reduce the damaging effect of ionizing radiation on spleen colony forming unit (CFU-S) population. Histone preparations stimulated colony-forming activity of bone marrow cells exposed to dose of 0.5-3.0 Gy both in the case of incubation with preparations and intravenous or intraperitoneal administration into recipients of irradiated cells. The effect of histones and accessory thymocytes on CFU-S population is compared

  8. [Effect of DOT1L gene silence on proliferation of acute monocytic leukemia cell line THP-1].

    Science.gov (United States)

    Zhang, Yu-Juan; Li, Hua-Wen; Chang, Guo-Qiang; Zhang, Hong-Ju; Wang, Jian; Lin, Ya-Ni; Zhou, Jia-Xi; Li, Qing-Hua; Pang, Tian-Xiang

    2013-08-01

    This study was aimed to investigate the influence of short hairpin RNA (shRNA) on proliferation of human leukemia cell line THP-1. The shRNA targeting the site 732-752 of DOT1L mRNA was designed and chemically synthesized, then a single-vector lentiviral, tet-inducible shRNA-DOT1L system (Plko-Tet-On) was generated. Thereafter, the THP-1 cells with lentivirus were infected to create stable cell line with regulatable shRNA expression. The expression of DOT1L in the THP-1 cell line was assayed by RT-PCR. Effect of shRNA-DOT1L on the proliferation of THP-1 cells was detected with MTT method,and the change of colony forming potential of THP-1 cells was analyzed by colony forming unit test. Cell cycle distribution was tested by flow cytometry. The results indicated that the expression of DOT1L was statistically lower than that in the control groups. The proliferation and colony forming capacity of THP-1 cells were significantly inhibited. The percentage of cells at G0/G1 phase increased in THP-1/shRNA cells treated with Dox while the percentage of cells at S phase significantly decreased as compared with that in the control group. It is concluded that the shRNA targeting DOT1L can effectively inhibit the proliferation of acute monocytic leukemia cell line THP-1.

  9. Enhancement of committed hematopoietic stem cell colony formation by nandrolone decanoate after sublethal whole body irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Gallicchio, V.S.; Chen, M.G.; Watts, T.D.

    1984-11-01

    The ability of an anabolic steroid, nandrolone decanoate, to increase committed topoietic stem cell (CFU-gm, CFU-e, and BFU-e) colony formation after sublethal irradiation was evaluated. Immediately after receiving whole body irradiation and on the next two days, each mouse was injected intraperitoneally with nandrolone decanoate (1.25 mg) in propylene glycol. Irradiated control mice received only propylene glycol. Compared to controls, drug-treated mice showed marked peripheral blood leukocytosis and more stable packed red cell volume. Drug-treated mice also demonstrated increased erythropoiesis, as CFU-e/BFU-e concentrations from both marrow (9% to 581%) and spleen (15% to 797%) were elevated. Granulopoiesis was increased similarly, as CFU-gm concentrations from marrow (38% to 685%) and spleen (9% to 373%) were elevated. These results demonstrate that nandrolone decanoate enhances hematopoietic stem cell recovery after sublethal whole body irradiation. This suggests that following hematopoietic suppression, nandrolone decanoate may stimulate the recovery of hematopoiesis at the stem cell level and in peripheral blood.

  10. Enhancement of committed hematopoietic stem cell colony formation by nandrolone decanoate after sublethal whole body irradiation

    International Nuclear Information System (INIS)

    Gallicchio, V.S.; Chen, M.G.; Watts, T.D.

    1984-01-01

    The ability of an anabolic steroid, nandrolone decanoate, to increase committed topoietic stem cell (CFU-gm, CFU-e, and BFU-e) colony formation after sublethal irradiation was evaluated. Immediately after receiving whole body irradiation and on the next two days, each mouse was injected intraperitoneally with nandrolone decanoate (1.25 mg) in propylene glycol. Irradiated control mice received only propylene glycol. Compared to controls, drug-treated mice showed marked peripheral blood leukocytosis and more stable packed red cell volume. Drug-treated mice also demonstrated increased erythropoiesis, as CFU-e/BFU-e concentrations from both marrow (9% to 581%) and spleen (15% to 797%) were elevated. Granulopoiesis was increased similarly, as CFU-gm concentrations from marrow (38% to 685%) and spleen (9% to 373%) were elevated. These results demonstrate that nandrolone decanoate enhances hematopoietic stem cell recovery after sublethal whole body irradiation. This suggests that following hematopoietic suppression, nandrolone decanoate may stimulate the recovery of hematopoiesis at the stem cell level and in peripheral blood

  11. Differentiation, Evaluation, and Application of Human Induced Pluripotent Stem Cell-Derived Endothelial Cells.

    Science.gov (United States)

    Lin, Yang; Gil, Chang-Hyun; Yoder, Mervin C

    2017-11-01

    The emergence of induced pluripotent stem cell (iPSC) technology paves the way to generate large numbers of patient-specific endothelial cells (ECs) that can be potentially delivered for regenerative medicine in patients with cardiovascular disease. In the last decade, numerous protocols that differentiate EC from iPSC have been developed by many groups. In this review, we will discuss several common strategies that have been optimized for human iPSC-EC differentiation and subsequent studies that have evaluated the potential of human iPSC-EC as a cell therapy or as a tool in disease modeling. In addition, we will emphasize the importance of using in vivo vessel-forming ability and in vitro clonogenic colony-forming potential as a gold standard with which to evaluate the quality of human iPSC-EC derived from various protocols. © 2017 American Heart Association, Inc.

  12. CD24 negative lung cancer cells, possessing partial cancer stem cell properties, cannot be considered as cancer stem cells.

    Science.gov (United States)

    Xu, Haineng; Mu, Jiasheng; Xiao, Jing; Wu, Xiangsong; Li, Maolan; Liu, Tianrun; Liu, Xinyuan

    2016-01-01

    Cancer stem cells (CSCs) play vital role in lung cancer progression, resistance, metastasis and relapse. Identifying lung CSCs makers for lung CSCs targeting researches are critical for lung cancer therapy. In this study, utilizing previous identified lung CSCs as model, we compared the expression of CD24, CD133 and CD44 between CSCs and non-stem cancer cells. Increased ratio of CD24- cells were found in CSCs. CD24- cells were then sorted by flow cytometry and their proliferative ability, chemo-resistance property and in vivo tumor formation abilities were detected. A549 CD24- cells formed smaller colonies, slower proliferated in comparison to A549 CD24+ cells. Besides, A549 CD24- exhibited stronger resistance to chemotherapy drug. However, A549 CD24- didn't exert any stronger tumor formation ability in vivo, which is the gold standard of CSCs. These results showed that CD24- A549 cells showed some properties of CSCs but not actually CSCs. This study provides evidence that CD24 cannot be considered as lung CSCs marker.

  13. Anticancer effects of kaempferol in A375 human malignant melanoma cells are mediated via induction of apoptosis, cell cycle arrest, inhibition of cell migration and downregulation of m-TOR/PI3K/AKT pathway.

    Science.gov (United States)

    Yang, Jia; Xiao, Peng; Sun, Jiaming; Guo, Liang

    2018-01-01

    Melanoma is an aggressive form of human cancer with limited treatment options currently available. The present study was aimed to evaluate the anticancer activity of kaempferol (KAM) against the human malignant melanoma A375 cell line along with evaluation of its effects on apoptosis, cell cycle, cell migration and m-TOR/PI3K/AKT pathway. Effects on cell viability were assessed by MTT assay while clonogenic assay measured the effects of KAM on colony formation. Annexin V assay evaluated the apoptotic effects of KAM in these cells using flow cytometry. Effects on cell cycle were determined by using flow cytometry with propidium iodide (PI) as probe. The effects of KAM on m-TOR/ PI3K/AKT signalling pathway were evaluated by western blot assay. MTT assay indicated that KAM exhibits a significant anticancer activity against A375 cells with an IC50 of 20 μM. These antiproliferative effects of KAM were also supported by the colony formation assay wherein KAM reduced the colony formation in a dose-dependent manner. The anticancer effect of KAM was found to be due to the initiation of apoptosis in human malignant melanoma A375 cells. Additionally, KAM also exhibited the capacity to trigger G2/M cell cycle arrest and to inhibit the cell migratory potential of A375 cells. KAM caused significant downregulation of m-TOR, phosphorylated (p) m-TOR, PI3K, p-PI3K and Akt protein levels in A375 malignantmelanoma cells. KAM exerts potent anticancer effects via induction of apoptosis, G2/M cell cycle arrest, cell migration inhibition and downregulation of m-TOR, pm-TOR, PI3K, p-PI3K and Akt protein levels.

  14. Characteristics of cells producing stimulator for the proliferation of colony forming unit-spleen (CFU-S)

    International Nuclear Information System (INIS)

    Abdul Manaf Ali; Wright, E.G.; Riches, A.C.

    1994-01-01

    The presence of stimulator for haemopoietic stem cell (CFU-S) proliferation in regenerating bone marrow was assayed by incubating the conditioned medium (CM) prepared from bone marrow with quiescent CFU-S from normal bone marrow. The percentage of CFU-S normal bone marrow in DNA synthesis increased more than 30 percent after incubating with CM of 4.5 Gy regenerating bone marrow. Stimulator was also present in bone marrow of mice at 9.0 Gy whole body X-irradiation. However the conditioned medium prepared from regenerating bone marrow without Fc and Ia-2k cells failed to increase the percentage of CFU-S in DNA synthesis. On the other hand, elimination of Thy 1.2 positive cells with complement cytolysis did not affect the ability of regenerating bone marrow to produce stimulator. These observations suggest that the stimulator producing cells are radio-resistant, Thy 1.2 negative, Fc and Ia-2k positive

  15. Gene expression profile and functionality of ESC-derived Lin-ckit+Sca-1+ cells are distinct from Lin-ckit+Sca-1+ cells isolated from fetal liver or bone marrow.

    Directory of Open Access Journals (Sweden)

    Irina Fernandez

    Full Text Available In vitro bioreactor-based cultures are being extensively investigated for large-scale production of differentiated cells from embryonic stem cells (ESCs. However, it is unclear whether in vitro ESC-derived progenitors have similar gene expression profiles and functionalities as their in vivo counterparts. This is crucial in establishing the validity of ESC-derived cells as replacements for adult-isolated cells for clinical therapies. In this study, we compared the gene expression profiles of Lin-ckit+Sca-1+ (LKS cells generated in vitro from mouse ESCs using either static or bioreactor-based cultures, with that of native LKS cells isolated from mouse fetal liver (FL or bone marrow (BM. We found that in vitro-generated LKS cells were more similar to FL- than to BM LKS cells in gene expression. Further, when compared to cells derived from bioreactor cultures, static culture-derived LKS cells showed fewer differentially expressed genes relative to both in vivo LKS populations. Overall, the expression of hematopoietic genes was lower in ESC-derived LKS cells compared to cells from BM and FL, while the levels of non-hematopoietic genes were up-regulated. In order to determine if these molecular profiles correlated with functionality, we evaluated ESC-derived LKS cells for in vitro hematopoietic-differentiation and colony formation (CFU assay. Although static culture-generated cells failed to form any colonies, they did differentiate into CD11c+ and B220+ cells indicating some hematopoietic potential. In contrast, bioreactor-derived LKS cells, when differentiated under the same conditions failed to produce any B220+ or CD11c+ cells and did not form colonies, indicating that these cells are not hematopoietic progenitors. We conclude that in vitro culture conditions significantly affect the transcriptome and functionality of ESC-derived LKS cells and although in vitro differentiated LKS cells were lineage negative and expressed both ckit and Sca-1

  16. Capacity of bone marrow colony forming unit-fibroblasts in vitro from mice with combined radiation-burn injury

    International Nuclear Information System (INIS)

    Chen Xinghua; Luo Chengji; Guo Chaohua; Wang Ping

    1999-01-01

    Objective: To investigate the capacity of bone marrow colony forming unit-fibroblasts (CFU-F) from mice with combined radiation-burn injury. Methods: Mice were treated with 5.0 Gy γ-ray radiation alone, 15% total body surface area (TBSA) III degree burn alone or combined radiation-burn. The numbers of CFU-Fs were assayed by Dexter's method. Results: The numbers of CFU-Fs from mice with radiation and combined radiation-burn injury were significantly decreased, compared with those of controls and mice with burn injury alone (P<0.05-0.01). conclusion: The results reveal that the repairing process of bone marrow stromal cells from mice with radiation injury and combined radiation-burn injury is slow, and the combined radiation-burn injury inflicted on the stromal cells possesses the characteristic of radiation injury

  17. Morphogen and community effects determine cell fates in response to BMP4 signaling in human embryonic stem cells.

    Science.gov (United States)

    Nemashkalo, Anastasiia; Ruzo, Albert; Heemskerk, Idse; Warmflash, Aryeh

    2017-09-01

    Paracrine signals maintain developmental states and create cell fate patterns in vivo and influence differentiation outcomes in human embryonic stem cells (hESCs) in vitro Systematic investigation of morphogen signaling is hampered by the difficulty of disentangling endogenous signaling from experimentally applied ligands. Here, we grow hESCs in micropatterned colonies of 1-8 cells ('µColonies') to quantitatively investigate paracrine signaling and the response to external stimuli. We examine BMP4-mediated differentiation in µColonies and standard culture conditions and find that in µColonies, above a threshold concentration, BMP4 gives rise to only a single cell fate, contrary to its role as a morphogen in other developmental systems. Under standard culture conditions BMP4 acts as a morphogen but this requires secondary signals and particular cell densities. We find that a 'community effect' enforces a common fate within µColonies, both in the state of pluripotency and when cells are differentiated, and that this effect allows a more precise response to external signals. Using live cell imaging to correlate signaling histories with cell fates, we demonstrate that interactions between neighbors result in sustained, homogenous signaling necessary for differentiation. © 2017. Published by The Company of Biologists Ltd.

  18. Stem cells are units of natural selection for tissue formation, for germline development, and in cancer development.

    Science.gov (United States)

    Weissman, Irving L

    2015-07-21

    It is obvious that natural selection operates at the level of individuals and collections of individuals. Nearly two decades ago we showed that in multi-individual colonies of protochordate colonial tunicates sharing a blood circulation, there exists an exchange of somatic stem cells and germline stem cells, resulting in somatic chimeras and stem cell competitions for gonadal niches. Stem cells are unlike other cells in the body in that they alone self-renew, so that they form clones that are perpetuated for the life of the organism. Stem cell competitions have allowed the emergence of competitive somatic and germline stem cell clones. Highly successful germline stem cells usually outcompete less successful competitors both in the gonads of the genotype partner from which they arise and in the gonads of the natural parabiotic partners. Therefore, natural selection also operates at the level of germline stem cell clones. In the colonial tunicate Botryllus schlosseri the formation of natural parabionts is prevented by a single-locus highly polymorphic histocompatibility gene called Botryllus histocompatibility factor. This limits germline stem cell predation to kin, as the locus has hundreds of alleles. We show that in mice germline stem cells compete for gonad niches, and in mice and humans, blood-forming stem cells also compete for bone marrow niches. We show that the clonal progression from blood-forming stem cells to acute leukemias by successive genetic and epigenetic events in blood stem cells also involves competition and selection between clones and propose that this is a general theme in cancer.

  19. Heterogeneity of clonogenic cells in acute myeloblastic leukemia.

    Science.gov (United States)

    Sabbath, K D; Ball, E D; Larcom, P; Davis, R B; Griffin, J D

    1985-02-01

    The expression of differentiation-associated surface antigens by the clonogenic leukemic cells from 20 patients with acute myeloblastic leukemia (AML) was studied with a panel of seven cytotoxic monoclonal antibodies (anti-Ia, -MY9, -PM-81, -AML-2-23, -Mol, -Mo2, and -MY3). The surface antigen phenotypes of the clonogenic cells were compared with the phenotypes of the whole leukemic cell population, and with the phenotypes of normal hematopoietic progenitor cells. In each case the clonogenic leukemic cells were found within a distinct subpopulation that was less "differentiated" than the total cell population. Clonogenic leukemic cells from different patients could be divided into three phenotype groups. In the first group (7 of 20 cases), the clonogenic cells expressed surface antigens characteristic of the normal multipotent colony-forming cell (Ia, MY9). These cases tended to have "undifferentiated" (FAB M1) morphology, and the total cell population generally lacked expression of "late" monocyte antigens such as MY3 and Mo2. A second group (seven cases) of clonogenic cells expressed surface antigens characteristic of an "early" (day 14) colony-forming unit granulocyte-monocyte (CFU-GM), and a third group (six cases) was characteristic of a "late" (day 7) CFU-GM. The cases in these latter two groups tended to have myelomonocytic (FAB M4) morphology and to express monocyte surface antigens. These results suggest that the clonogenic cells are a distinct subpopulation in all cases of AML, and may be derived from normal hematopoietic progenitor cells at multiple points in the differentiation pathway. The results further support the possibility that selected monoclonal antibodies have the potential to purge leukemic clonogenic cells from bone marrow in some AML patients without eliminating critical normal progenitor cells.

  20. Characterization of bone marrow derived mesenchymal stem cells in suspension

    Science.gov (United States)

    2012-01-01

    Introduction Bone marrow mesenchymal stem cells (BMMSCs) are a heterogeneous population of postnatal precursor cells with the capacity of adhering to culture dishes generating colony-forming unit-fibroblasts (CFU-F). Here we identify a new subset of BMMSCs that fail to adhere to plastic culture dishes and remain in culture suspension (S-BMMSCs). Methods To catch S-BMMSCs, we used BMMSCs-produced extracellular cell matrix (ECM)-coated dishes. Isolated S-BMMSCs were analyzed by in vitro stem cell analysis approaches, including flow cytometry, inductive multiple differentiation, western blot and in vivo implantation to assess the bone regeneration ability of S-BMMSCs. Furthermore, we performed systemic S-BMMSCs transplantation to treat systemic lupus erythematosus (SLE)-like MRL/lpr mice. Results S-BMMSCs are capable of adhering to ECM-coated dishes and showing mesenchymal stem cell characteristics with distinction from hematopoietic cells as evidenced by co-expression of CD73 or Oct-4 with CD34, forming a single colony cluster on ECM, and failure to differentiate into hematopoietic cell lineage. Moreover, we found that culture-expanded S-BMMSCs exhibited significantly increased immunomodulatory capacities in vitro and an efficacious treatment for SLE-like MRL/lpr mice by rebalancing regulatory T cells (Tregs) and T helper 17 cells (Th17) through high NO production. Conclusions These data suggest that it is feasible to improve immunotherapy by identifying a new subset BMMSCs. PMID:23083975

  1. Metabolic differentiation of surface and invasive cells of yeast colony biofilms revealed by gene expression profiling

    Czech Academy of Sciences Publication Activity Database

    Maršíková, J.; Wilkinson, D.; Hlaváček, Otakar; Gilfillan, G.D.; Mizeranschi, A.; Hughes, T.; Begany, Markéta; Rešetárová, Stanislava; Váchová, Libuše; Palková, Z.

    2017-01-01

    Roč. 18, OCT 23 (2017), s. 814 ISSN 1471-2164 R&D Projects: GA MŠk(CZ) 7F14083; GA MŠk(CZ) LQ1604; GA MŠk(CZ) ED1.1.00/02.0109 Institutional support: RVO:61388971 Keywords : Saccharomyces cerevisiae * Colony biofilms * Cell differentiation Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 3.729, year: 2016

  2. Method of forming a package for MEMS-based fuel cell

    Science.gov (United States)

    Morse, Jeffrey D; Jankowski, Alan F

    2013-05-21

    A MEMS-based fuel cell package and method thereof is disclosed. The fuel cell package comprises seven layers: (1) a sub-package fuel reservoir interface layer, (2) an anode manifold support layer, (3) a fuel/anode manifold and resistive heater layer, (4) a Thick Film Microporous Flow Host Structure layer containing a fuel cell, (5) an air manifold layer, (6) a cathode manifold support structure layer, and (7) a cap. Fuel cell packages with more than one fuel cell are formed by positioning stacks of these layers in series and/or parallel. The fuel cell package materials such as a molded plastic or a ceramic green tape material can be patterned, aligned and stacked to form three dimensional microfluidic channels that provide electrical feedthroughs from various layers which are bonded together and mechanically support a MEMS-based miniature fuel cell. The package incorporates resistive heating elements to control the temperature of the fuel cell stack. The package is fired to form a bond between the layers and one or more microporous flow host structures containing fuel cells are inserted within the Thick Film Microporous Flow Host Structure layer of the package.

  3. Renal cells express different forms of vimentin: the independent expression alteration of these forms is important in cell resistance to osmotic stress and apoptosis.

    Directory of Open Access Journals (Sweden)

    Bettina S Buchmaier

    Full Text Available Osmotic stress has been shown to regulate cytoskeletal protein expression. It is generally known that vimentin is rapidly degraded during apoptosis by multiple caspases, resulting in diverse vimentin fragments. Despite the existence of the known apoptotic vimentin fragments, we demonstrated in our study the existence of different forms of vimentin VIM I, II, III, and IV with different molecular weights in various renal cell lines. Using a proteomics approach followed by western blot analyses and immunofluorescence staining, we proved the apoptosis-independent existence and differential regulation of different vimentin forms under varying conditions of osmolarity in renal cells. Similar impacts of osmotic stress were also observed on the expression of other cytoskeleton intermediate filament proteins; e.g., cytokeratin. Interestingly, 2D western blot analysis revealed that the forms of vimentin are regulated independently of each other under glucose and NaCl osmotic stress. Renal cells, adapted to high NaCl osmotic stress, express a high level of VIM IV (the form with the highest molecular weight, besides the three other forms, and exhibit higher resistance to apoptotic induction with TNF-α or staurosporin compared to the control. In contrast, renal cells that are adapted to high glucose concentration and express only the lower-molecular-weight forms VIM I and II, were more susceptible to apoptosis. Our data proved the existence of different vimentin forms, which play an important role in cell resistance to osmotic stress and are involved in cell protection against apoptosis.

  4. The interaction between Sertoli cells and luekemia inhibitory factor on the propagation and differentiation of spermatogonial stem cells in vitro.

    Science.gov (United States)

    Rastegar, Tayebeh; Habibi Roudkenar, Mehryar; Parvari, Soraya; Baazm, Maryam

    2015-11-01

    Sertoli cells play a pivotal role in creating microenvironments essential for spermatogonial stem cells (SSCs) self-renewal and commitment to differentiation. Maintenance of SSCs and or induction of in vitro spermiogenesis may provide a therapeutic strategy to treat male infertility. This study investigated the role of luekemia inhibitory factor (LIF) on the propagation of SSCs and both functions of Sertoli cells on the proliferation and differentiation of these cells. SSCs were sorted from the testes of adult male mice by magnetic activated cell sorting and thymus cell antigen 1 antibody. On the other hand, isolated Sertoli cells were enriched using lectin coated plates. SSCs were cultured on Sertoli cells for 7 days in the absence or presence of LIF. The effects of these conditions were evaluated by microscopy and expression of meiotic and post meiotic transcripts by reverse transcriptase polymerase chain reaction. Our data showed that SSCs co-cultured with Sertoli cells in the presence of LIF formed colonies on top of the Sertoli cells. These colonies had alkaline phosphatesase activity and expressed SSCs specific genes. SSCs were enjoyed limited development after the mere removal of LIF, and exhibiting expression of meiotic and postmeiotic transcript and loss of SSCs specific gene expression (p< 0.05). Our findings represent co-culture of SSCs with Sertoli cells provides conditions that may allow efficient proliferation and differentiation of SSCs for male infertility treatment.

  5. Biologic activities of recombinant human-beta-defensin-4 toward cultured human cancer cells.

    Science.gov (United States)

    Gerashchenko, O L; Zhuravel, E V; Skachkova, O V; Khranovska, N N; Filonenko, V V; Pogrebnoy, P V; Soldatkina, M A

    2013-06-01

    The aim of the study was in vitro analysis of biological activity of recombinant human beta-defensin-4 (rec-hBD-4). hBD-4 cDNA was cloned into pGEX-2T vector, and recombinant plasmid was transformed into E. coli BL21(DE3) cells. To purify soluble fusion GST-hBD-4 protein, affinity chromatography was applied. Rec-hBD-4 was cleaved from the fusion protein with thrombin, and purified by reverse phase chromatography on Sep-Pack C18. Effects of rec-hBD-4 on proliferation, viability, cell cycle distribution, substrate-independent growth, and mobility of cultured human cancer cells of A431, A549, and TPC-1 lines were analyzed by direct cell counting technique, MTT assay, flow cytofluorometry, colony forming assay in semi-soft medium, and wound healing assay. Rec-hBD-4 was expressed in bacterial cells as GST-hBD-4 fusion protein, and purified by routine 3-step procedure (affine chromatography on glutathione-agarose, cleavage of fusion protein by thrombin, and reverse phase chromatography). Analysis of in vitro activity of rec-hBD-4 toward three human cancer cell lines has demonstrated that the defensin is capable to affect cell behaviour in concentration-dependent manner. In 1-100 nM concentrations rec-hBD-4 significantly stimulates cancer cell proliferation and viability, and promotes cell cycle progression through G2/M checkpoint, greatly enhances colony-forming activity and mobility of the cells. Treatment of the cells with 500 nM of rec-hBD-4 resulted in opposite effects: significant suppression of cell proliferation and viability, blockage of cell cycle in G1/S checkpoint, significant inhibition of cell migration and colony forming activity. Recombinant human beta-defensin-4 is biologically active peptide capable to cause oppositely directed effects toward biologic features of cancer cells in vitro dependent on its concentration.

  6. The effect of cilengitide in combination with irradiation and chemotherapy in head and neck squamous cell carcinoma cell lines

    International Nuclear Information System (INIS)

    Heiduschka, G.; Lill, C.; Schneider, S.; Kotowski, U.; Thurnher, D.; Seemann, R.; Kornek, G.; Schmid, R.

    2014-01-01

    Integrins are highly attractive targets in oncology due to their involvement in angiogenesis in a wide spectrum of cancer entities. Among several integrin inhibitors under clinical evaluation, cilengitide is the most promising compound. However, little is known about the cellular processes induced during cilengitide therapy in combination with irradiation and cisplatin in head and neck squamous cell carcinoma (HNSCC). The cytostatic effect of cilengitide was assessed by proliferation assay in the three HNSCC cell lines SCC25, FaDu and CAL27. Combination experiments with cisplatin and irradiation were performed. Possible synergistic effects were calculated in combination index (CI) analyses. Colony forming inhibition was investigated in clonogenic assays. Real-time PCR arrays were used to evaluate target protein gene expression patterns. Flow cytometry was used to detect apoptosis. Used alone, cilengitide has only minor cytotoxic effects in HNSCC cell lines. However, combination with cisplatin resulted in synergistic growth inhibition in all three cell lines. Irradiation showed synergism in short-term experiments and in colony forming assays, an additive effect was detected. Real-time PCR assay detected downregulation of the antiapoptotic protein Bcl-2 after exposure of cells to cilengitide. Cilengitide in combination with cisplatin and irradiation may be a feasible option for the treatment of patients with head and neck cancer. However, further investigations are required to understand the exact mechanism that leads to synergistic cytotoxicity. (orig.) [de

  7. Stem cell mobilization by granulocyte colony-stimulating factor for myocardial recovery after acute myocardial infarction: a meta-analysis

    DEFF Research Database (Denmark)

    Zohlnhofer, D.; Dibra, A.; Koppara, T.

    2008-01-01

    OBJECTIVES: The objective of this meta-analysis was to evaluate the effect of stem cell mobilization by granulocyte colony-stimulating factor (G-CSF) on myocardial regeneration on the basis of a synthesis of the data generated by randomized, controlled clinical trials of G-CSF after acute...

  8. Number and proliferative capacity of osteogenic stem cells are maintained during aging and in patients with osteoporosis

    DEFF Research Database (Denmark)

    Stenderup, Karin; Justesen, J.; Eriksen, E.F.

    2001-01-01

    Decreased bone formation is an important pathophysiological mechanism responsible for bone loss associated with aging and osteoporosis. Osteoblasts (OBs), originate from mesenchymal stem cells (MSCs) that are present in the bone marrow and form colonies (termed colony-forming units-fibroblastic [...

  9. Solare Cell Roof Tile And Method Of Forming Same

    Science.gov (United States)

    Hanoka, Jack I.; Real, Markus

    1999-11-16

    A solar cell roof tile includes a front support layer, a transparent encapsulant layer, a plurality of interconnected solar cells and a backskin layer. The front support layer is formed of light transmitting material and has first and second surfaces. The transparent encapsulant layer is disposed adjacent the second surface of the front support layer. The interconnected solar cells has a first surface disposed adjacent the transparent encapsulant layer. The backskin layer has a first surface disposed adjacent a second surface of the interconnected solar cells, wherein a portion of the backskin layer wraps around and contacts the first surface of the front support layer to form the border region. A portion of the border region has an extended width. The solar cell roof tile may have stand-offs disposed on the extended width border region for providing vertical spacing with respect to an adjacent solar cell roof tile.

  10. Ink-Jet Printer Forms Solar-Cell Contacts

    Science.gov (United States)

    Alexander, Paul, Jr.; Vest, R. W.; Binford, Don A.; Tweedell, Eric P.

    1988-01-01

    Contacts formed in controllable patterns with metal-based inks. System forms upper metal contact patterns on silicon photovoltaic cells. Uses metallo-organic ink, decomposes when heated, leaving behind metallic, electrically conductive residue in printed area.

  11. Gallic acid induced apoptotic events in HCT-15 colon cancer cells

    Science.gov (United States)

    Subramanian, Aruna Priyadharshni; Jaganathan, Saravana Kumar; Mandal, Mahitosh; Supriyanto, Eko; Muhamad, Ida Idayu

    2016-01-01

    AIM: To investigate the inhibitory action of diet-derived phenolic compound gallic acid (GA) against HCT-15 colon cancer cells. METHODS: The antiproliferative effect of GA against colon cancer cells was determined by performing thiazolyl blue tetrazolium bromide (MTT) assay. The colony forming ability of GA treated colon cancer cells was evaluated using the colony forming assay. The cell cycle changes induced by GA in HCT-15 cells were analyzed by propidium iodide staining. Levels of reactive oxygen species (ROS) and mitochondrial membrane potential of HCT-15 exposed to GA was assessed using 2’,7’-dichlorfluorescein-diacetate and rhodamine-123 respectively, with the help of flow cytometry. Morphological changes caused by GA treatment in the colon cancer cells were identified by scanning electron microscope and photomicrograph examination. Apoptosis was confirmed using flow cytometric analysis of GA treated HCT-15 cells after staining with Yo-Pro-1. RESULTS: MTT assay results illustrated that GA has an inhibitory effect on HCT-15 cells with IC50 value of 740 μmol/L. A time-dependent inhibition of colony formation was evident with GA treatment. Cell cycle arrest was evident from the accumulation of GA treated HCT-15 cells at sub-G1 phase (0.98 ± 1.03 vs 58.01 ± 2.05) with increasing exposure time. Flow cytometric analysis of GA treated HCT-15 cells depicted early events associated with apoptosis like lipid layer breakage and fall in mitochondrial membrane potential apart from an increase in the generation of ROS which were in a time dependent manner. SEM and photomicrograph images of the GA-treated cells displayed membrane blebbing and cell shrinking characteristics of apoptosis. Further apoptosis confirmation by Yo-Pro-1 staining also showed the time-dependent increase of apoptotic cells after treatment. CONCLUSION: These results show that GA induced ROS dependent apoptosis and inhibited the growth of colon cancer cells. PMID:27099438

  12. Pattern changes in quantitative and qualitative markers of hematopoietic stem cells during acute and chronic exposure to Sr"9"0 isotope in cell culture

    International Nuclear Information System (INIS)

    Russu, Yi.Z.; Byil'ko, D.Yi.; Byil'ko, N.M.; Rodyionova, N.K.

    2015-01-01

    To study the condition of stem cells and their immediate progenitors we implemented cell culture methodology in vivo in gel diffusion capsules with subsequent analysis of the colonies and clusters. On the basis of experiments it was established that long-term effects of incorporated "9"0 Sr isotope leads to significant disturbances in the hematopoietic system and in particular, revealing changes in hematological parameters of irradiated animals such as the appearance of circulating progenitor cells in peripheral blood, reducing the colony-forming efficiency of the bone marrow derived progenitor cells, as well as quantitative and qualitative changes in the clones. Indices confirm the connection of the detected effects in individuals exposed to ionizing radiation described in the earlier publications and can serve as basis for developing criteria for the formation of risk groups among people exposed to "9"0 Sr

  13. Radiation and thermal characteristics of mouse lymphoma cells and their radiation-sensitive mutant

    International Nuclear Information System (INIS)

    Baba, Yuji; Yasunaga, Tadamasa; Uozumi, Hideaki; Takahashi, Mutsumasa; Sawada, Shozo.

    1988-01-01

    Radiation and thermal characteristics of L5178Y cells and their radiation-sensitive mutant M10 cells were studied by the colony-forming method and the dye-exclusion method using eosin-Y. Although M10 cells were remarkably radiation-sensitive compared with L5178Y cells, it was diffcult to cause interphase death of M10 after a large dose of irradiation. After heat treatments, L5178Y cells revealed more cell destruction and were stained well by eosin-Y, but it was relatively difficult to produce cell destruction of M10 cells, which showed poor staining by eosin-Y. When assayed by the colony-forming method, M10 cells were also heat-resistant compared to L5178Y. The dye-exclusion rate was closely correlated with cell survival after hyperthermia of L5178Y cells, suggesting that this is a simple method of detecting the thermosensitivity and thermotolerance of cancer cells. The difference in survival of L5178Y cells and M10 cells after combined treatment with gamma irradiation and hyperthermia was smaller than with gamma irradiation alone. It was also found that there was a relationship between radiation-induced interphase death and hyperthermia-induced interphase death, and that interphase death accounted for a major part of cell death caused by hyperthermia in mouse leukemia cells. (author)

  14. Activation of human gingival epithelial cells by cell-surface components of black-pigmented bacteria: augmentation of production of interleukin-8, granulocyte colony-stimulating factor and granulocyte-macrophage colony-stimulating factor and expression of intercellular adhesion molecule 1.

    Science.gov (United States)

    Sugiyama, A; Uehara, A; Iki, K; Matsushita, K; Nakamura, R; Ogawa, T; Sugawara, S; Takada, H

    2002-01-01

    Black-pigmented anaerobic bacteria, such as Porphyromonas gingivalis and Prevotella intermedia, are amongst the predominant bacteria in periodontal pockets and have been implicated in periodontal diseases. To elucidate the roles of gingival keratinocytes, which are the first cells encountered by oral bacteria in periodontal diseases, human gingival keratinocytes in primary culture were stimulated with cell-surface components of P gingivalis and Pr. intermedia. A glycoprotein fraction from Pr. intermedia (PGP) clearly augmented the release of interleukin-8, granulocyte colony-stimulating factor and granulocyte-macrophage colony-stimulating factor, as determined by enzyme-linked immunosorbent assay. This PGP also induced expression of intercellular adhesion molecule-1 (ICAM-1), as determined by flow cytometry. The augmentation of mRNA expression for these molecules was also confirmed by reverse transcription PCR. In contrast, lipopolysaccharide (LPS) from Pr. intermedia and Escherichia coli was completely inactive in these assays. LPS fraction and purified fimbriae from P gingivalis exhibited weak activities. Cytokine production and ICAM-1 expression by gingival keratinocytes might cause accumulation and activation of neutrophils in the epithelium and, therefore, may be involved in the initiation and development of inflammation in periodontal tissues.

  15. Growth Mechanism of Microbial Colonies

    Science.gov (United States)

    Zhu, Minhui; Martini, K. Michael; Kim, Neil H.; Sherer, Nicholas; Lee, Jia Gloria; Kuhlman, Thomas; Goldenfeld, Nigel

    Experiments on nutrient-limited E. coli colonies, growing on agar gel from single cells reveal a power-law distribution of sizes, both during the growth process and in the final stage when growth has ceased. We developed a Python simulation to study the growth mechanism of the bacterial population and thus understand the broad details of the experimental findings. The simulation takes into account nutrient uptake, metabolic function, growth and cell division. Bacteria are modeled in two dimensions as hard circle-capped cylinders with steric interactions and elastic stress dependent growth characteristics. Nutrient is able to diffuse within and between the colonies. The mechanism of microbial colony growth involves reproduction of cells within the colonies and the merging of different colonies. We report results on the dynamic scaling laws and final state size distribution, that capture in semi-quantitative detail the trends observed in experiment. Supported by NSF Grant 0822613.

  16. Effects of x-ray and neutron irradiation on spherical colonies

    International Nuclear Information System (INIS)

    Aramaki, Ryoji

    1980-01-01

    Responses of in vitro cultured mammalian cells in spherical colonies to 200 kVp x-rays and D-T neutrons were studied using reproductive capacity as a criterion for survival. Cell lines used were FM3A, L5 and Chinese hamster V79. The spherical colonies exposed to x-rays exhibited two-component survival curves. All cells used were more radio-resistant in spherical colonies than in single cell suspensions. It was suggested that this difference in response was attributable to the presence of hypoxic cells in spherical colonies. Dose-modifying Factor (DMF), the ratios of D 0 of the second slopes of the curves for spherical colonies to those for single cells, were 1.6 for FM3A, 1.8 for L5, and 1.7 for Chinese hamster V79. The hypoxic cell fractions in spherical colonies for FM3A, L5, and Chinese hamster V79, were 0.1, 0.6 and 0.4, respectively, resulting in variations in cell survival in spherical colonies following x-radiation. No significant difference was observed between responses of spherical colonies and single cell suspensions to D-T neutrons. FM3A and Chinese hamster V79 showed two-component survival curves when irradiated with neutrons at 37 0 C, but not at 25 0 C. The repair of potentially lethal and sub-lethal damage was also investigated using FM3A in spherical colonies. No detectable repair of potentially lethal damage was observed for x-rays and D-T neutrons. The effect of neutron fractionation was considerably smaller for spherical colonies as compared to single cells. (author)

  17. Radioresistant canine hematopoietic cells

    International Nuclear Information System (INIS)

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

    1987-01-01

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

  18. Development of a high-titer retrovirus producer cell line capable of gene transfer into rhesus monkey hematopoietic stem cells

    International Nuclear Information System (INIS)

    Bodine, D.M.; McDonagh, K.T.; Brandt, S.J.; Ney, P.A.; Agricola, B.; Byrne, E.; Nienhuis, A.W.

    1990-01-01

    Retroviral-mediated gene transfer into primitive hematopoietic cells has been difficult to achieve in large-animal models. The authors have developed an amphotropic producer clone that generates >10 10 recombinant retroviral particles (colony-forming units) per ml of culture medium. Autologous rhesus monkey bone marrow cells were cocultured with either high or low titer producer clones for 4-6 days and reinfused into sublethally irradiated animals. The proviral genome was detected in blood and bone-marrow cells from all three animals reconstituted with cells cocultured with the high-titer producer cells. In contrast, three animals reconstituted with bone marrow cocultured with the low-titer producer clone exhibited no evidence of gene transfer

  19. Colletotrichum higginsianum Mitogen-Activated Protein Kinase ChMK1: Role in Growth, Cell Wall Integrity, Colony Melanization and Pathogenicity

    Directory of Open Access Journals (Sweden)

    Wei Wei

    2016-08-01

    Full Text Available Colletotrichum higginsianum is an economically important pathogen that causes anthracnose disease in a wide range of cruciferous crops. To facilitate the efficient control of anthracnose disease, it will be important to understand the mechanism by which the cruciferous crops and C. higginsianum interact. A key step in understanding this interaction is characterizing the mitogen-activated protein kinases (MAPK signaling pathway of C. higginsianum. MAPK plays important roles in diverse physiological processes of multiple pathogens. In this study, a Fus3/Kss1-related MAPK gene, ChMK1, from C. higginsianum was analyzed. The results showed that the Fus3/Kss1-related MAPK ChMK1 plays a significant role in cell wall integrity. Targeted deletion of ChMK1 resulted in a hypersensitivity to cell wall inhibitors, reduced conidiation and albinistic colonies. Further, the deletion mutant was also unable to form melanized appressorium, a specialized infection structure that is necessary for successful infection. Therefore, the deletion mutant loses pathogenicity on A. thaliana leaves, demonstrating that ChMK1 plays an essential role in the early infection step. In addition, the ChMK1 deletion mutant showed an attenuated growth rate that is different from that of its homologue in C. lagenarium, indicating the diverse roles that Fus3/Kss1-related MAPKs plays in phytopathogenic fungi. Furthermore, the expression level of three melanin synthesis associated genes were clearly decreased in the albinistic ChMK1 mutant compared to that of the wild type strain, suggesting that ChMK1 is also required for colony melanization in C. higginsianum.

  20. The In Vitro Anti-Tumor Activity of Phycocyanin against Non-Small Cell Lung Cancer Cells

    Directory of Open Access Journals (Sweden)

    Shuai Hao

    2018-05-01

    Full Text Available Phycocyanin, a type of functional food colorant, is shown to have a potent anti-cancer property. Non-small cell lung cancer (NSCLC is one of the most aggressive form of cancers with few effective therapeutic options. Previous studies have demonstrated that phycocyanin exerts a growth inhibitory effect on NSCLC A549 cells. However, its biological function and underlying regulatory mechanism on other cells still remain unknown. Here, we investigated the in vitro function of phycocyanin on three typical NSCLC cell lines, NCI-H1299, NCI-H460, and LTEP-A2, for the first time. The results showed that phycocyanin could significantly induce apoptosis, cell cycle arrest, as well as suppress cell migration, proliferation, and the colony formation ability of NSCLC cells through regulating multiple key genes. Strikingly, phycocyanin was discovered to affect the cell phenotype through regulating the NF-κB signaling of NSCLC cells. Our findings demonstrated the anti-neoplastic function of phycocyanin and provided valuable information for the regulation of phycocyanin in NSCLC cells.

  1. Growth-inhibiting effect of tumor necrosis factor on human umbilical vein endothelial cells is enhanced with advancing age in vitro

    International Nuclear Information System (INIS)

    Shimada, Y.; Kaji, K.; Ito, H.; Noda, K.; Matsuo, M.

    1990-01-01

    We have examined the effects of in vitro aging on the growth capacity of human umbilical vein endothelial cells (HUVECs) under the influence of tumor necrosis factor (TNF) with or without interferon-gamma (IFN-gamma). The growth and colony-forming abilities of control cells were impaired with advancing age in vitro, especially at later stages (more than 70-80% of life span completed). It was found that treatment with TNF inhibited growth and colony-forming efficiency at any in vitro age. The effects of TNF were shown to increase with increasing in vitro age, as reflected by a more pronounced increase in doubling times, a decrease in saturation density, and a reduction in colony-forming efficiency. However, the characteristics of TNF receptors, including the dissociation constant, and the number of TNF-binding sites per cell-surface area remained rather constant. The effect of TNF was augmented by IFN-gamma at a dose that alone affected growth and colony formation only slightly. The augmentation by IFN-gamma was also found to depend on in vitro age; the synergy with TNF in the deterioration of colony-forming ability was observed only in aged cells. These results suggest that the intrinsic responsiveness of HUVECs to growth-inhibiting factors, as well as to growth-stimulating factors, changes during aging in vitro

  2. Oral Mucosa Harbors a High Frequency of Endothelial Cells: A Novel Postnatal Cell Source for Angiogenic Regeneration.

    Science.gov (United States)

    Zhou, Jian; Rogers, Jason H; Lee, Scott H; Sun, DongMing; Yao, Hai; Mao, Jeremy J; Kong, Kimi Y

    2017-01-15

    Endothelial progenitor cells/endothelial cells (EPCs/ECs) have great potential to treat pathological conditions such as cardiac infarction, muscle ischemia, and bone fractures, but isolation of EPC/ECs from existing cell sources is challenging due to their low EC frequency. We have isolated endothelial progenitor (EP)-like cells from rat oral mucosa and characterized their yield, immunophenotype, growth, and in vivo angiogenic potential. The frequency of EP-like cells derived from oral mucosa is thousands of folds higher than EPCs derived from donor-match bone marrow samples. EP-like cells from oral mucosa were positive for EC markers CD31, VE-Cadherin, and VEGFR2. Oral mucosa-derived EP-like cells displayed robust uptake of acetylated low-density lipoprotein and formed stable capillary networks in Matrigel. Subcutaneously implanted oral mucosa-derived EP-like cells anastomosed with host blood vessels, implicating their ability to elicit angiogenesis. Similar to endothelial colony-forming cells, EP-like cells from oral mucosa have a significantly higher proliferative rate than human umbilical vein endothelial cells. These findings identify a putative EPC source that is easily accessible in the oral cavity, potentially from discarded tissue specimens, and yet with robust yield and potency for angiogenesis in tissue and organ regeneration.

  3. Recruitment of host's progenitor cells to sites of human amniotic fluid stem cells implantation.

    Science.gov (United States)

    Mirabella, Teodelinda; Poggi, Alessandro; Scaranari, Monica; Mogni, Massimo; Lituania, Mario; Baldo, Chiara; Cancedda, Ranieri; Gentili, Chiara

    2011-06-01

    The amniotic fluid is a new source of multipotent stem cells with a therapeutic potential for human diseases. Cultured at low cell density, human amniotic fluid stem cells (hAFSCs) were still able to generate colony-forming unit-fibroblast (CFU-F) after 60 doublings, thus confirming their staminal nature. Moreover, after extensive in vitro cell expansion hAFSCs maintained a stable karyotype. The expression of genes, such as SSEA-4, SOX2 and OCT3/4 was confirmed at early and later culture stage. Also, hAFSCs showed bright expression of mesenchymal lineage markers and immunoregulatory properties. hAFSCs, seeded onto hydroxyapatite scaffolds and subcutaneously implanted in nude mice, played a pivotal role in mounting a response resulting in the recruitment of host's progenitor cells forming tissues of mesodermal origin such as fat, muscle, fibrous tissue and immature bone. Implanted hAFSCs migrated from the scaffold to the skin overlying implant site but not to other organs. Given their in vivo: (i) recruitment of host progenitor cells, (ii) homing towards injured sites and (iii) multipotentiality in tissue repair, hAFSCs are a very appealing reserve of stem cells potentially useful for clinical application in regenerative medicine. Copyright © 2011 Elsevier Ltd. All rights reserved.

  4. Reprogramming of somatic cells induced by fusion of embryonic stem cells using hemagglutinating virus of Japan envelope (HVJ-E)

    International Nuclear Information System (INIS)

    Yue, Xiao-shan; Fujishiro, Masako; Toyoda, Masashi; Akaike, Toshihiro; Ito, Yoshihiro

    2010-01-01

    In this research, hemagglutinating virus of Japan envelope (HVJ-E) was used to reprogram somatic cells by fusion with mouse embryonic stem (ES) cells. Neomycin-resistant mouse embryonic fibroblasts (MEFs) were used as somatic cells. Nanog-overexpressing puromycin-resistant EB3 cells were used as mouse ES cells. These two cells were fused by exposing to HVJ-E and the generated fusion cells were selected by puromycin and G418 to get the stable fusion cell line. The fusion cells form colonies in feeder-free culture system. Microsatellite analysis of the fusion cells showed that they possessed genes from both ES cells and fibroblasts. The fusion cells were tetraploid, had alkali phosphatase activity, and expressed stem cell marker genes such as Pou5f1, Nanog, and Sox2, but not the fibroblast cell marker genes such as Col1a1 and Col1a2. The pluripotency of fusion cells was confirmed by their expression of marker genes for all the three germ layers after differentiation induction, and by their ability to form teratoma which contained all the three primary layers. Our results show that HVJ-E can be used as a fusion reagent for reprogramming of somatic cells.

  5. Reprogramming of somatic cells induced by fusion of embryonic stem cells using hemagglutinating virus of Japan envelope (HVJ-E)

    Energy Technology Data Exchange (ETDEWEB)

    Yue, Xiao-shan [Nano Medical Engineering Laboratory, RIKEN Advanced Science Institute, 2-1 Hirosawa, Wako-shi, Saitama 351-0198 (Japan); Department of Biomolecular Engineering, Graduate School of Bioscience and Technology, Tokyo Institute of Technology, Nagatsuta-cho, Midori-ku, Yokohama-shi, Kanagawa 226-8501 (Japan); Fujishiro, Masako [Nano Medical Engineering Laboratory, RIKEN Advanced Science Institute, 2-1 Hirosawa, Wako-shi, Saitama 351-0198 (Japan); Toyoda, Masashi [Department of Reproductive Biology, National Institute for Child Health and Development, 2-10-1, Okura, Setagaya-ku, Tokyo 157-8535 (Japan); Akaike, Toshihiro [Department of Biomolecular Engineering, Graduate School of Bioscience and Technology, Tokyo Institute of Technology, Nagatsuta-cho, Midori-ku, Yokohama-shi, Kanagawa 226-8501 (Japan); Ito, Yoshihiro, E-mail: y-ito@riken.jp [Nano Medical Engineering Laboratory, RIKEN Advanced Science Institute, 2-1 Hirosawa, Wako-shi, Saitama 351-0198 (Japan); Department of Biomolecular Engineering, Graduate School of Bioscience and Technology, Tokyo Institute of Technology, Nagatsuta-cho, Midori-ku, Yokohama-shi, Kanagawa 226-8501 (Japan)

    2010-04-16

    In this research, hemagglutinating virus of Japan envelope (HVJ-E) was used to reprogram somatic cells by fusion with mouse embryonic stem (ES) cells. Neomycin-resistant mouse embryonic fibroblasts (MEFs) were used as somatic cells. Nanog-overexpressing puromycin-resistant EB3 cells were used as mouse ES cells. These two cells were fused by exposing to HVJ-E and the generated fusion cells were selected by puromycin and G418 to get the stable fusion cell line. The fusion cells form colonies in feeder-free culture system. Microsatellite analysis of the fusion cells showed that they possessed genes from both ES cells and fibroblasts. The fusion cells were tetraploid, had alkali phosphatase activity, and expressed stem cell marker genes such as Pou5f1, Nanog, and Sox2, but not the fibroblast cell marker genes such as Col1a1 and Col1a2. The pluripotency of fusion cells was confirmed by their expression of marker genes for all the three germ layers after differentiation induction, and by their ability to form teratoma which contained all the three primary layers. Our results show that HVJ-E can be used as a fusion reagent for reprogramming of somatic cells.

  6. ANTITUMOR AND APOPTOTIC EFFECTS OF CUCURBITACIN A IN A-549 LUNG CARCINOMA CELLS IS MEDIATED VIA G2/M CELL CYCLE ARREST AND M-TOR/PI3K/AKT SIGNALLING PATHWAY.

    Science.gov (United States)

    Wang, Wen-Dong; Liu, Yan; Su, Yuan; Xiong, Xian-Zhi; Shang, Dan; Xu, Juan-Juan; Liu, Hong-Ju

    2017-01-01

    The main aim of this study was to demonstrate the antitumor potential of cucurbitacin A on A-549 NSCLC (non-small cell lung cancer cells). The effects of Cucurbitacin A on apoptotic induction, cell physic, cell cycle failure and m-TOR/PI3K/Akt signalling pathway were also investigated in the present study. MTT assay and clonogenic assay were carried out to study effects of this compound on cell cytotoxicity and colony forming tendency in A-549 cells. Moreover, phase and fluorescence microscopic techniques were used to examine the effects on cell morphology and induction of apoptosis. The effects on cell cycle phase distribution were investigated by flow cytometry and effects on m-TOR/PI3K/Akt signalling proteins were assessed by western blot analysis. Results showed that cucurbitacin A induced dose-dependent cytotoxic effects along with suppressing the colony forming tendency in these cells. Cucurbitacin A also induced morphological changes in these cells featuring chromatin condensation, cell shrinkage and apoptotic body formation. G2/M phase cell cycle collapse was also induced by Cucurbitacin A along with inhibition of expression levels of m-TOR/PI3K/Akt proteins. In conclusion, cucurbitacin A inhibits cancer growth in A-549 NSCLC cells by inducing apoptosis, targeting m-TOR/PI3K/Akt signalling pathway and G2/M cell cycle.

  7. Positioning of the sensor cell on the sensing area using cell trapping pattern in incubation type planar patch clamp biosensor.

    Science.gov (United States)

    Wang, Zhi-Hong; Takada, Noriko; Uno, Hidetaka; Ishizuka, Toru; Yawo, Hiromu; Urisu, Tsuneo

    2012-08-01

    Positioning the sensor cell on the micropore of the sensor chip and keeping it there during incubation are problematic tasks for incubation type planar patch clamp biosensors. To solve these problems, we formed on the Si sensor chip's surface a cell trapping pattern consisting of a lattice pattern with a round area 5 μm deep and with the micropore at the center of the round area. The surface of the sensor chip was coated with extra cellular matrix collagen IV, and HEK293 cells on which a chimera molecule of channel-rhodopsin-wide-receiver (ChR-WR) was expressed, were then seeded. We examined the effects of this cell trapping pattern on the biosensor's operation. In the case of a flat sensor chip without a cell trapping pattern, it took several days before the sensor cell covered the micropore and formed an almost confluent state. As a result, multi-cell layers easily formed and made channel current measurements impossible. On the other hand, the sensor chip with cell trapping pattern easily trapped cells in the round area, and formed the colony consisted of the cell monolayer covering the micropore. A laser (473 nm wavelength) induced channel current was observed from the whole cell arrangement formed using the nystatin perforation technique. The observed channel current characteristics matched measurements made by using a pipette patch clamp. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. Functional State of Haemopoietic Stem Cells in the Irradiated Mouse

    Energy Technology Data Exchange (ETDEWEB)

    Silini, G.; Pozzi, Laura V. [Laboratorio di Radiobiologica Animale, Centro Studi Nucleari, Casaccia, Rome (Italy)

    1968-08-15

    The repopulation kinetics of bone marrow in irradiated (C3H x C57BL) F{sub 1} hybrid mice were followed at different time intervals after a single whole-body dose of 150 rad X -rays. The changes in the number of total nucleated cells and of colony-forming cells were estimated and expressed as number of cells per femur shaft of fixed length. For the evaluation of the progenitor cell compartment an exogenous test of transplantation into heavily irradiated hosts followed by spleen colony counts was employed. In an attempt to distinguish between cycling and dormant cells in the progenitor pool, vinblastine was also administered under various schedules of treatment with respect to time and dosage to follow the changes induced by this drug in the irradiated recovering marrow. The depopulation of total bone-m arrow cells caused by vinblastine proceeded at a comparable rate in both the irradiated and the normal mouse. On the other hand, depopulation of the colony-formers is faster in animals irradiated 1 -2 days previously as compared with normal animals or mice irradiated 1 week or 2 weeks earlier. The data were interpreted to show that in the marrow of a newly-irradiated animal more cells are in a fast cycle than in a normal or a recovering animal. Data are finally presented and discussed concerning the use of vinblastine for studies of stem cell kinetics in haemopoietic tissues. (author)

  9. The interaction between Sertoli cells and luekemia inhibitory factor on the propagation and differentiation of spermatogonial stem cells in vitro

    Directory of Open Access Journals (Sweden)

    Tayebeh Rastegar

    2015-11-01

    Full Text Available Background: Sertoli cells play a pivotal role in creating microenvironments essential for spermatogonial stem cells (SSCs self-renewal and commitment to differentiation. Maintenance of SSCs and or induction of in vitro spermiogenesis may provide a therapeutic strategy to treat male infertility. Objective: This study investigated the role of luekemia inhibitory factor (LIF on the propagation of SSCs and both functions of Sertoli cells on the proliferation and differentiation of these cells. Materials and Methods: SSCs were sorted from the testes of adult male mice by magnetic activated cell sorting and thymus cell antigen 1 antibody. On the other hand, isolated Sertoli cells were enriched using lectin coated plates. SSCs were cultured on Sertoli cells for 7 days in the absence or presence of LIF. The effects of these conditions were evaluated by microscopy and expression of meiotic and post meiotic transcripts by reverse transcriptase polymerase chain reaction. Results: Our data showed that SSCs co-cultured with Sertoli cells in the presence of LIF formed colonies on top of the Sertoli cells. These colonies had alkaline phosphatesase activity and expressed SSCs specific genes. SSCs were enjoyed limited development after the mere removal of LIF, and exhibiting expression of meiotic and postmeiotic transcript and loss of SSCs specific gene expression (p< 0.05. Conclusion: Our findings represent co-culture of SSCs with Sertoli cells provides conditions that may allow efficient proliferation and differentiation of SSCs for male infertility treatment.

  10. Co-culture with podoplanin+ cells protects leukemic blast cells with leukemia-associated antigens in the tumor microenvironment.

    Science.gov (United States)

    Lee, Ji Yoon; Han, A-Reum; Lee, Sung-Eun; Min, Woo-Sung; Kim, Hee-Je

    2016-05-01

    Podoplanin+ cells are indispensable in the tumor microenvironment. Increasing evidence suggests that podoplanin may support the growth and metastasis of solid tumors; however, to the best of our knowledge no studies have determined whether or not podoplanin serves a supportive role in acute myeloid leukemia (AML). The effects of co‑culture with podoplanin+ cells on the cellular activities of the leukemic cells, such as apoptosis and cell proliferation, in addition to the expression of podoplanin in leukemic cells, were investigated. Due to the fact that genetic abnormalities are the primary cause of leukemogenesis, the overexpression of the fibromyalgia‑like tyrosine kinase‑3 gene in colony forming units was also examined following cell sorting. Podoplanin+ cells were found to play a protective role against apoptosis in leukemic cells and to promote cell proliferation. Tumor‑associated antigens, including Wilms' tumor gene 1 and survivin, were increased when leukemic cells were co‑cultured with podoplanin+ cells. In combination, the present results also suggest that podoplanin+ cells can function as stromal cells for blast cell retention in the AML tumor microenvironment.

  11. Turnover of circulating hematopoietic stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Dorie, M J; Maloney, M A; Patt, H M

    1979-10-01

    Short-term parabiosis of male and female CBA/CaJ mice was used to investigate the turnover of circulating hematopoietic stem cells. The change and subsequent disappearance of donor stem cells were monitored by spleen colony assay and chromosome analysis of individual colonies. The results revealed an exponential disappearance of pluripotent stem cells from blood with a characteristic half time of 1.7 h. Blood-borne stem cells were shown to be equilibrated with a subpopulation of marrow stem cells exhibiting a disappearance half time of 9.5 h. Splenectomy did not change the apparent rate of stem cell removal from the blood.

  12. The human umbilical cord blood: a potential source for osteoblast progenitor cells

    DEFF Research Database (Denmark)

    Kjeldsen, Cecilia Rosada; Melsvik, Dorte; Ebbesen, Peter

    2003-01-01

    -density mononuclear cells isolated from hUCB formed few adherent colonies with fibroblast-like morphology after a few days in culture. At confluence, the polyclonal cell populations were characterized. Using FACS analysis and immunocytochemistry, the cells were found to express HLA-ABC, CD9, vimentin, the b subunit...... visualized by Alizarin red staining. In the presence of normal horse serum and dexamethasone (10(-7) M), the cells formed foci of adipocytes. When the cells were implanted mixed with hydroxyapatite/tricalcium phosphate powder in the subcutis of immunocompromised mice for 8 weeks, they formed osteogenic...... tissue and a myelosupportive microenviroment that enclosed hematopoietic cells and adipocytes. Our results demonstrate the presence of circulating stem cells with osteogenic and adipogenic differentiation potential in hUCB and may encourage the use of hUCB as a potential source for stem cells...

  13. Blastema from rabbit ear contains progenitor cells comparable to marrow derived mesenchymal stem cells

    Directory of Open Access Journals (Sweden)

    Mohamadreza Baghaban Eslaminejad

    2012-09-01

    Full Text Available Rabbits have the capacity to regenerate holes in their ears by forming a blastema, a tissue that is made up of a group of undifferentiated cells. The purpose of the present study was to isolate and characterize blastema progenitor cells and compare them with marrow mesenchymal stem cells (MSCs. Five New Zealand white male rabbits were used in the present study. A 2-mm hole was created in the animal ears. After 4 days, the blastema ring formed in the periphery of the hole was removed and cultivated. The cells were expanded through several subcultures and compared with the MSCs derived from the marrow of same animal in terms of in vitro differentiation capacity, growth kinetics and culture requirements for optimal proliferation. The primary cultures from both cells tended to be heterogeneous. Fibroblastic cells became progressively dominant with advancing passages. Similar to MSCs blastema passaged-3 cells succeeded to differentiate into bone, cartilage and adipose cell lineages. Even lineage specific genes tended to express in higher level in blastema cells compared to MSCs (p < 0.05. Moreover blastema cells appeared more proliferative; producing more colonies (p < 0.05. While blastema cells showed extensive proliferation in 15% fetal bovine serum (FBS, MSCs displayed higher expansion rate at 10% FBS. In conclusion, blastema from rabbit ear contains a population of fibroblastic cells much similar in characteristic to bone marrow mesenchymal stem cells. However, the two cells were different in the level of lineage-specific gene expression, the growth curve characteristics and the culture requirements.

  14. Macrophage colony-stimulating factor receptor marks and regulates a fetal myeloid-primed B-cell progenitor in mice.

    Science.gov (United States)

    Zriwil, Alya; Böiers, Charlotta; Wittmann, Lilian; Green, Joanna C A; Woll, Petter S; Jacobsen, Sten Eirik W; Sitnicka, Ewa

    2016-07-14

    Although it is well established that unique B-cell lineages develop through distinct regulatory mechanisms during embryonic development, much less is understood about the differences between embryonic and adult B-cell progenitor cells, likely to underpin the genetics and biology of infant and childhood PreB acute lymphoblastic leukemia (PreB-ALL), initiated by distinct leukemia-initiating translocations during embryonic development. Herein, we establish that a distinct subset of the earliest CD19(+) B-cell progenitors emerging in the E13.5 mouse fetal liver express the colony-stimulating factor-1 receptor (CSF1R), previously thought to be expressed, and play a lineage-restricted role in development of myeloid lineages, and macrophages in particular. These early embryonic CSF1R(+)CD19(+) ProB cells also express multiple other myeloid genes and, in line with this, possess residual myeloid as well as B-cell, but not T-cell lineage potential. Notably, these CSF1R(+) myeloid-primed ProB cells are uniquely present in a narrow window of embryonic fetal liver hematopoiesis and do not persist in adult bone marrow. Moreover, analysis of CSF1R-deficient mice establishes a distinct role of CSF1R in fetal B-lymphopoiesis. CSF1R(+) myeloid-primed embryonic ProB cells are relevant for infant and childhood PreB-ALLs, which frequently have a bi-phenotypic B-myeloid phenotype, and in which CSF1R-rearrangements have recently been reported. © 2016 by The American Society of Hematology.

  15. Hemopoietic stem-cell compartment of the SCID mouse: Double-exponential survival curve after γ irradiation

    International Nuclear Information System (INIS)

    Taniguchi, Satoshi; Hirabayashi, Yoko; Inoue, Tohru; Kanisawa, Masayoshi; Sasaki, Hideki; Komatsu, Kenshi; Mori, K.J.

    1993-01-01

    It has been reported that SCID (severe combined immunodeficiency, scid/scid) mice are more radiosensitive than normal mice. In the present studies, graded doses of radiation were given to bone marrow cells from SCID mice, and double-exponential survival curves were observed for day-9 and day-12 colony-forming units in the spleen (CFU-S). Single-exponential curves were found for SCID CFU in in vitro assays for granulocyte/macrophage-CFUs and erythroid burst-forming units, as reported elsewhere. Since the size of this more resistant fraction seems to decrease with stem-cell maturation, the finding implies that this fraction is a primitive subpopulation of the stem-cell compartment. The mean lethal dose (D 0 ), however, of this less sensitive SCID CFU-S is much less than the D 0 of regular CFU-S in normal littermates. Spleen colonies produced by SCID bone marrow were relatively small and abortive. The size of these colonies decreased nearly exponentially with increasing doses of radiation. These colonies produced by the sensitive fraction have disappeared, being killed by a relatively low dose of radiation. This observation might account for the high lymphomagenesis arising from primitive hemopoietic stem cells in SCID mice, because the smallness of the colonies suggests that there is unrepaired or misrepaired damage. Furthermore, this less sensitive fraction might be a source of the open-quotes leakyclose quotes change of T and B cells, possibly due to the induction of an equivocal repair system which appears in the later stages of life in the SCID mice. 34 refs., 5 figs., 3 tabs

  16. DNA repair capacity and rate of excision repair in UV-irradiated mammalian cells

    International Nuclear Information System (INIS)

    Inoue, Masao; Takebe, Hiraku.

    1978-01-01

    Repair capacities of five mammalian cell strains were measured by colony-forming ability, HCR of UV-irradiated virus, UDS, pyrimidine dimer excision, and semi-conservative DNA replication. Colony-forming ability of UV-irradiated cells was high for human amnion FL cells and mouse L cells, slightly low for African green monkey CV-1 cells, and extremely low for xeroderma pigmentosum cells. HCR of UV-irradiated Herpes simplex virus was high in CV-1 cells, FL and normal human fibroblast cells, low in both XP and L cells. The amount of UDS was high in FL and normal human fibroblast cells, considerably low in CV-1 cells, and essentially no UDS was observed in XP cells. Rate of UDS after UV-irradiation was slower for CV-1 cells than FL and human fibroblast cells. Rate of the excision of thymine-containing dimers from the acid-insoluble fraction during post-irradiation incubation of the cells was rapid in FL and normal human cells and slow in CV-1 cells, and no excision took place in XP cells. Semi-conservative DNA synthesis was reduced after UV-irradiation in all cell lines, but subsequently recovered in FL, normal human and CV-1 cells. The onset of recovery was 4 h after UV-irradiation for FL and normal human cells, but about 6 h for CV-1 cells. The apparent intermediate repair of CV-1 cells except for HCR may be related to the slow rate of excision repair. ''Patch and cut'' model is more favorable than ''cut and patch'' model to elucidate these results. (auth.)

  17. Manipulation of signaling thresholds in "engineered stem cell niches" identifies design criteria for pluripotent stem cell screens.

    Directory of Open Access Journals (Sweden)

    Raheem Peerani

    Full Text Available In vivo, stem cell fate is regulated by local microenvironmental parameters. Governing parameters in this stem cell niche include soluble factors, extra-cellular matrix, and cell-cell interactions. The complexity of this in vivo niche limits analyses into how individual niche parameters regulate stem cell fate. Herein we use mouse embryonic stem cells (mESC and micro-contact printing (microCP to investigate how niche size controls endogenous signaling thresholds. microCP is used to restrict colony diameter, separation, and degree of clustering. We show, for the first time, spatial control over the activation of the Janus kinase/signal transducer and activator of transcription pathway (Jak-Stat. The functional consequences of this niche-size-dependent signaling control are confirmed by demonstrating that direct and indirect transcriptional targets of Stat3, including members of the Jak-Stat pathway and pluripotency-associated genes, are regulated by colony size. Modeling results and empirical observations demonstrate that colonies less than 100 microm in diameter are too small to maximize endogenous Stat3 activation and that colonies separated by more than 400 microm can be considered independent from each other. These results define parameter boundaries for the use of ESCs in screening studies, demonstrate the importance of context in stem cell responsiveness to exogenous cues, and suggest that niche size is an important parameter in stem cell fate control.

  18. Intracellular vesicles as reproduction elements in cell wall-deficient L-form bacteria.

    Directory of Open Access Journals (Sweden)

    Yves Briers

    Full Text Available Cell wall-deficient bacteria, or L-forms, represent an extreme example of bacterial plasticity. Stable L-forms can multiply and propagate indefinitely in the absence of a cell wall. Data presented here are consistent with the model that intracellular vesicles in Listeria monocytogenes L-form cells represent the actual viable reproductive elements. First, small intracellular vesicles are formed along the mother cell cytoplasmic membrane, originating from local phospholipid accumulation. During growth, daughter vesicles incorporate a small volume of the cellular cytoplasm, and accumulate within volume-expanding mother cells. Confocal Raman microspectroscopy demonstrated the presence of nucleic acids and proteins in all intracellular vesicles, but only a fraction of which reveals metabolic activity. Following collapse of the mother cell and release of the daughter vesicles, they can establish their own membrane potential required for respiratory and metabolic processes. Premature depolarization of the surrounding membrane promotes activation of daughter cell metabolism prior to release. Based on genome resequencing of L-forms and comparison to the parental strain, we found no evidence for predisposing mutations that might be required for L-form transition. Further investigations revealed that propagation by intracellular budding not only occurs in Listeria species, but also in L-form cells generated from different Enterococcus species. From a more general viewpoint, this type of multiplication mechanism seems reminiscent of the physicochemical self-reproducing properties of abiotic lipid vesicles used to study the primordial reproduction pathways of putative prokaryotic precursor cells.

  19. Intracellular vesicles as reproduction elements in cell wall-deficient L-form bacteria.

    Science.gov (United States)

    Briers, Yves; Staubli, Titu; Schmid, Markus C; Wagner, Michael; Schuppler, Markus; Loessner, Martin J

    2012-01-01

    Cell wall-deficient bacteria, or L-forms, represent an extreme example of bacterial plasticity. Stable L-forms can multiply and propagate indefinitely in the absence of a cell wall. Data presented here are consistent with the model that intracellular vesicles in Listeria monocytogenes L-form cells represent the actual viable reproductive elements. First, small intracellular vesicles are formed along the mother cell cytoplasmic membrane, originating from local phospholipid accumulation. During growth, daughter vesicles incorporate a small volume of the cellular cytoplasm, and accumulate within volume-expanding mother cells. Confocal Raman microspectroscopy demonstrated the presence of nucleic acids and proteins in all intracellular vesicles, but only a fraction of which reveals metabolic activity. Following collapse of the mother cell and release of the daughter vesicles, they can establish their own membrane potential required for respiratory and metabolic processes. Premature depolarization of the surrounding membrane promotes activation of daughter cell metabolism prior to release. Based on genome resequencing of L-forms and comparison to the parental strain, we found no evidence for predisposing mutations that might be required for L-form transition. Further investigations revealed that propagation by intracellular budding not only occurs in Listeria species, but also in L-form cells generated from different Enterococcus species. From a more general viewpoint, this type of multiplication mechanism seems reminiscent of the physicochemical self-reproducing properties of abiotic lipid vesicles used to study the primordial reproduction pathways of putative prokaryotic precursor cells.

  20. The effect of resveratrol in combination with irradiation and chemotherapy. Study using Merkel cell carcinoma cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Heiduschka, G. [Medical University of Vienna, Department of Otorhinolaryngology, Head and Neck Surgery, Vienna (Austria); Medical University of Vienna, Clinical Pharmacology, Vienna (Austria); Lill, C.; Brunner, M.; Thurnher, D. [Medical University of Vienna, Department of Otorhinolaryngology, Head and Neck Surgery, Vienna (Austria); Seemann, R. [Medical University of Vienna, Maxillo-Facial Surgery, Vienna (Austria); Schmid, R. [Medical University of Vienna, Radiotherapy and -biology, Vienna (Austria); Houben, R. [University Hospital Wuerzburg, Department of Dermatology, Wuerzburg (Germany); Bigenzahn, J. [CeMM-Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna (Austria)

    2014-01-15

    Merkel cell carcinoma (MCC) is a rare, but highly malignant tumor of the skin. In case of systemic disease, possible therapeutic options include irradiation or chemotherapy. The aim of this study was to evaluate whether the flavonoid resveratrol enhances the effect of radiotherapy or chemotherapy in MCC cell lines. The two MCC cell lines MCC13 and MCC26 were treated with increasing doses of resveratrol. Combination experiments were conducted with cisplatin and etoposide. Colony forming assays were performed after sequential irradiation with 1, 2, 3, 4, 6, and 8 Gy and apoptosis was assessed with flow cytometry. Expression of cancer drug targets was analyzed by real-time PCR array. Resveratrol is cytotoxic in MCC cell lines. Cell growth is inhibited by induction of apoptosis. The combination with cisplatin and etoposide resulted in a partially synergistic inhibition of cell proliferation. Resveratrol and irradiation led to a synergistic reduction in colony formation compared to irradiation alone. Evaluation of gene expression did not show significant difference between the cell lines. Due to its radiosensitizing effect, resveratrol seems to be a promising agent in combination with radiation therapy. The amount of chemosensitizing depends on the cell lines tested. (orig.) [German] Das Merkelzellkarzinom (MCC) ist ein seltener, jedoch hochmaligner Tumor der Haut. Sowohl Strahlentherapie oder Chemotherapie sind moegliche therapeutische Optionen. In dieser Studie wurde untersucht, ob das Flavonoid Resveratrol die Wirkung der Strahlen- oder Chemotherapie in MCC-Zelllinien verbessert. Die beiden MCC-Zelllinien MCC13 und MCC26 wurden mit ansteigenden Dosen von Resveratrol behandelt. Kombinationsexperimente wurden mit Cisplatin und Etoposid durchgefuehrt und die Koloniebildung in ''Colony-Forming''-Assays nach erfolgter sequentieller Bestrahlung mit 1, 2, 3, 4, 6 und 8 Gy gemessen. Desweiteren wurde die Apoptose mittels Durchflusszytometrie bestimmt. Die

  1. Long-term injury in B-lymphocyte precursor cells in repeatedly-irradiated mice

    International Nuclear Information System (INIS)

    Hendry, J.H.; Clarke, D.; Testa, N.; Kimber, J.

    1984-01-01

    Mice irradiated with 4 doses of 4,5 Gy X-rays at 3-week intervals, demonstrated long-term proliferative defects in B lymphocytes. There was a reduced mitogenic response to bacterial polysaccharide (30%), a lower concentration (35%) of B-lymphocyte colony-forming cells (BL-CFC) in agar with an increased proportion of clusters (x2), and a reduced concentration (30%) of plaque-forming cells. Grafts of thymocytes were able to restore the levels of BL-CFC in the short term, but in the long term large grafts of femoral marrow cells were much better in restoring the numbers of BL-CFC. The reduced mitogenesis (25%) of splenocytes by concanavalin A and the diminished number of plaque-forming cells, may suggest persistent injury in T-B cell cooperation

  2. Octanoate in Human Albumin Preparations Is Detrimental to Mesenchymal Stromal Cell Culture

    Directory of Open Access Journals (Sweden)

    Way-Wua Wong

    2015-01-01

    Full Text Available Cell therapies hold great promise as the next major advance in medical treatment. To enable safe, effective ex vivo culture whilst maintaining cell phenotype, growth media constituents must be carefully controlled. We have used a chemically defined mesenchymal stromal cell culture medium to investigate the influence of different preparations of human serum albumin. We examined two aspects of cell culture, growth rate as measured by population doubling time and colony forming ability which is a representative measure of the stemness of the cell population. Albumin preparations showed comparative differences in both of these criteria. Analysis of the albumin bound fatty acids also showed differences depending on the manufacturing procedure used. We demonstrated that octanoate, an additive used to stabilize albumin during pasteurization, slows growth and lowers colony forming ability during ex vivo culture. Further to this we also found the level of Na+/K+ ATPase, a membrane bound cation pump inhibited by octanoate, is increased in cells exposed to this compound. We conclude that the inclusion of human serum albumin in ex vivo growth media requires careful consideration of not only the source of albumin, but also the associated molecular cargo, for optimal cell growth and behavior.

  3. Chronic Exposure to Particulate Nickel Induces Neoplastic Transformation in Human Lung Epithelial Cells

    Directory of Open Access Journals (Sweden)

    Amie L. Holmes

    2013-11-01

    Full Text Available Nickel is a well-known human lung carcinogen with the particulate form being the most potent; however, the carcinogenic mechanism remains largely unknown. Few studies have investigated the genotoxicity and carcinogenicity of nickel in its target cell, human bronchial epithelial cells. Thus, the goal of this study was to investigate the effects of particulate nickel in human lung epithelial cells. We found that nickel subsulfide induced concentration- and time-dependent increases in both cytotoxicity and genotoxicity in human lung epithelial cells (BEP2D. Chronic exposure to nickel subsulfide readily induced cellular transformation, inducing 2.55, 2.9 and 2.35 foci per dish after exposure to 1, 2.5 and 5 μg/cm2 nickel subsulfide, respectively. Sixty-one, 100 and 70 percent of the foci isolated from 1, 2.5, and 5 μg/cm2 nickel subsulfide treatments formed colonies in soft agar and the degree of soft agar colony growth increased in a concentration-dependent manner. Thus, chronic exposure to particulate nickel induces genotoxicity and cellular transformation in human lung epithelial cells.

  4. 3D tissue formation by stacking detachable cell sheets formed on nanofiber mesh.

    Science.gov (United States)

    Kim, Min Sung; Lee, Byungjun; Kim, Hong Nam; Bang, Seokyoung; Yang, Hee Seok; Kang, Seong Min; Suh, Kahp-Yang; Park, Suk-Hee; Jeon, Noo Li

    2017-03-23

    We present a novel approach for assembling 3D tissue by layer-by-layer stacking of cell sheets formed on aligned nanofiber mesh. A rigid frame was used to repeatedly collect aligned electrospun PCL (polycaprolactone) nanofiber to form a mesh structure with average distance between fibers 6.4 µm. When human umbilical vein endothelial cells (HUVECs), human foreskin dermal fibroblasts, and skeletal muscle cells (C2C12) were cultured on the nanofiber mesh, they formed confluent monolayers and could be handled as continuous cell sheets with areas 3 × 3 cm 2 or larger. Thicker 3D tissues have been formed by stacking multiple cell sheets collected on frames that can be nested (i.e. Matryoshka dolls) without any special tools. When cultured on the nanofiber mesh, skeletal muscle, C2C12 cells oriented along the direction of the nanofibers and differentiated into uniaxially aligned multinucleated myotube. Myotube cell sheets were stacked (upto 3 layers) in alternating or aligned directions to form thicker tissue with ∼50 µm thickness. Sandwiching HUVEC cell sheets with two dermal fibroblast cell sheets resulted in vascularized 3D tissue. HUVECs formed extensive networks and expressed CD31, a marker of endothelial cells. Cell sheets formed on nanofiber mesh have a number of advantages, including manipulation and stacking of multiple cell sheets for constructing 3D tissue and may find applications in a variety of tissue engineering applications.

  5. X-ray-induced production of granulocyte-macrophage colony-stimulating factor (GM-CSF) by mouse spleen cells in culture

    International Nuclear Information System (INIS)

    Onoda, M.; Shinoda, M.; Tsuneoka, K.; Shikita, M.

    1980-01-01

    Spleen cells were collected from normal mice and cultured in a medium containing 20% calf serum. Addition of lipopolysaccharide (LPS) in the culture significantly increased the production of granulocyte-macrophage colony-stimulating factor (GM-CSF), and a maximum induction was attained in 5 days. Irradiation of the spleen cells with 300 to 3000 R x rays also enhanced the production of GM-CSF, but there was a latent period of about 5 days before the factor appeared in the culture medium. The observed difference between LPS and x rays in the timing of inducing GM-CSF production in the spleen cell culture was consistent with the difference observed in animals. These results suggest that different mechanisms of GM-CSF production operate in the spleen in response to either LPS or x rays

  6. Natural killer cell lines preferentially kill clonogenic multiple myeloma cells and decrease myeloma engraftment in a bioluminescent xenograft mouse model.

    Science.gov (United States)

    Swift, Brenna E; Williams, Brent A; Kosaka, Yoko; Wang, Xing-Hua; Medin, Jeffrey A; Viswanathan, Sowmya; Martinez-Lopez, Joaquin; Keating, Armand

    2012-07-01

    Novel therapies capable of targeting drug resistant clonogenic MM cells are required for more effective treatment of multiple myeloma. This study investigates the cytotoxicity of natural killer cell lines against bulk and clonogenic multiple myeloma and evaluates the tumor burden after NK cell therapy in a bioluminescent xenograft mouse model. The cytotoxicity of natural killer cell lines was evaluated against bulk multiple myeloma cell lines using chromium release and flow cytometry cytotoxicity assays. Selected activating receptors on natural killer cells were blocked to determine their role in multiple myeloma recognition. Growth inhibition of clonogenic multiple myeloma cells was assessed in a methylcellulose clonogenic assay in combination with secondary replating to evaluate the self-renewal of residual progenitors after natural killer cell treatment. A bioluminescent mouse model was developed using the human U266 cell line transduced to express green fluorescent protein and luciferase (U266eGFPluc) to monitor disease progression in vivo and assess bone marrow engraftment after intravenous NK-92 cell therapy. Three multiple myeloma cell lines were sensitive to NK-92 and KHYG-1 cytotoxicity mediated by NKp30, NKp46, NKG2D and DNAM-1 activating receptors. NK-92 and KHYG-1 demonstrated 2- to 3-fold greater inhibition of clonogenic multiple myeloma growth, compared with killing of the bulk tumor population. In addition, the residual colonies after treatment formed significantly fewer colonies compared to the control in a secondary replating for a cumulative clonogenic inhibition of 89-99% at the 20:1 effector to target ratio. Multiple myeloma tumor burden was reduced by NK-92 in a xenograft mouse model as measured by bioluminescence imaging and reduction in bone marrow engraftment of U266eGFPluc cells by flow cytometry. This study demonstrates that NK-92 and KHYG-1 are capable of killing clonogenic and bulk multiple myeloma cells. In addition, multiple myeloma

  7. Isolation and In Vitro Characterization of Epidermal Stem Cells

    DEFF Research Database (Denmark)

    Moestrup, Kasper S; Andersen, Marianne Stemann; Jensen, Kim Bak

    2017-01-01

    flow cytometry. Using markers that define the spatial origin of epidermal cells, it is possible to interrogate the specific characteristics of subpopulations of cells based on their in vivo credentials. Here, we describe how to isolate, culture, and characterize keratinocytes from murine back and tail......Colony-forming assays represent prospective methods, where cells isolated from enzymatically dissociated tissues or from tissue cultures are assessed for their proliferative capacity in vitro. Complex tissues such as the epithelial component of the skin (the epidermis) are characterized...

  8. Evaluation of the secretion and release of vascular endothelial growth factor from two-dimensional culture and three-dimensional cell spheroids formed with stem cells and osteoprecursor cells.

    Science.gov (United States)

    Lee, Hyunjin; Lee, Sung-Il; Ko, Youngkyung; Park, Jun-Beom

    2018-05-18

    Co-culture has been applied in cell therapy, including stem cells, and has been reported to give enhanced functionality. In this study, stem-cell spheroids were formed in concave micromolds at different ratios of stem cells to osteoprecursor cells, and the amount of secretion of vascular endothelial growth factor (VEGF) was evaluated. Gingiva-derived stem cells and osteoprecursor cells in the amount of 6 × 105 were seeded on a 24-well culture plate or concave micromolds. The ratios of stem cells to osteoprecursor cells included: 0:4 (group 1), 1:3 (group 2), 2:2 (group 3), 3:1 (group 4), and 4:0 (group 5). The morphology of cells in a 2-dimensional culture (groups 1-5) showed a fibroblast-like appearance. The secretion of VEGF increased with the increase in stem cells, and a statistically significant increase was noted in groups 3, 4 and 5 when compared with the media-only group (p cells formed spheroids in concave microwells, and no noticeable change in the morphology was noted with the increase in stem cells. Spheroids containing stem cells were positive for the stem-cell markers SSEA-4. The secretion of VEGF from cell spheroids increased with the increase in stem cells. This study showed that cell spheroids formed with stem cells and osteoprecursor cells with different ratios, using microwells, had paracrine effects on the stem cells. The secretion of VEGF increased with the increase in stem cells. This stem-cell spheroid may be applied for tissue-engineering purposes.

  9. Radiosensitivity and thermoresistance of rat RA-2 rhabdomyosarcoma cells

    International Nuclear Information System (INIS)

    Fedorova, E.V.; Trusova, V.D.; Vakhtin, Yu.B.

    1990-01-01

    The data obtained show that clonogenic RA-2T cells are 2-3 times more thermoresistant than clonogenic cells of the original thermosensitive RA-2T strain as estimated by D 0 value upon heating up to 43-45 deg C. After X-irradiation of rat rhabdomyosarcoma, a decrease in the capacity of forming pulmonary colonies is more pronounced in cells of the thermosensitive RA-2 strain cells than in those of the thermoresistant strain RA-2T (D 0 =1.6 Gy and D 0 =2.4 Gy, respectively). In all appearance, within one and the same tumor cell population, the hereditarily thermoresistant cells are more radioresistant than the thermosensitive ones

  10. Differential bone-forming capacity of osteogenic cells from either embryonic stem cells or bone marrow-derived mesenchymal stem cells

    NARCIS (Netherlands)

    Both, Sanne Karijn; van Apeldoorn, Aart A.; Jukes, J.M.; Englund, Mikael C.O.; Hyllner, Johan; van Blitterswijk, Clemens; de Boer, Jan

    2011-01-01

    For more than a decade, human mesenchymal stem cells (hMSCs) have been used in bone tissue-engineering research. More recently some of the focus in this field has shifted towards the use of embryonic stem cells. While it is well known that hMSCs are able to form bone when implanted subcutaneously in

  11. X-ray-induced in vitro neoplastic transformation of human diploid cells

    International Nuclear Information System (INIS)

    Borek, C.

    1980-01-01

    Techniques have recently been developed to identify and score quantitatively neoplastic transformation caused by x-rays in cultured cells derived from rodents. The present report describes for the first time the neoplastic transformation in vitro of human diploid cells by x-ray irradiation into cells which can progress in vitro into advanced stages of neoplastic development, namely, to form colonies in agar and give rise to tumors when injected into nude mice

  12. Solar cell modules with improved backskin and methods for forming same

    Science.gov (United States)

    Hanoka, Jack I.

    1998-04-21

    A laminated solar cell module with a backskin layer that reduces the materials and labor required during the manufacturing process. The solar cell module includes a rigid front support layer formed of light transmitting material having first and second surfaces. A transparent encapsulant layer has a first surface disposed adjacent the second surface of the front support layer. A plurality of interconnected solar cells have a first surface disposed adjacent a second surface of the transparent encapsulant layer. The backskin layer is formed of a thermoplastic olefin, which includes first ionomer, a second ionomer, glass fiber, and carbon black. A first surface of the backskin layer is disposed adjacent a second surface of the interconnected solar cells. The transparent encapsulant layer and the backskin layer, in combination, encapsulate the interconnected solar cells. An end portion of the backskin layer can be wrapped around the edge of the module for contacting the first surface of the front support layer to form an edge seal. A laminated solar cell module with a backskin layer that reduces the materials and labor required during the manufacturing process. The solar cell module includes a rigid front support layer formed of light transmitting material having first and second surfaces. A transparent encapsulant layer has a first surface disposed adjacent the second surface of the front support layer. A plurality of interconnected solar cells have a first surface disposed adjacent a second surface of the transparent encapsulant layer. The backskin layer is formed of a thermoplastic olefin, which includes first ionomer, a second ionomer, glass fiber, and carbon black. A first surface of the backskin layer is disposed adjacent a second surface of the interconnected solar cells. The transparent encapsulant layer and the backskin layer, in combination, encapsulate the interconnected solar cells. An end portion of the backskin layer can be wrapped around the edge of the

  13. Poly (ADP-ribose) metabolism in alkylated mouse L5178Y cells

    International Nuclear Information System (INIS)

    Boyle, J.M.

    1985-01-01

    Poly ADP-ribosylation of two mouse lymphoma cell lines, L5178Y (LS) and the radiation and alkylating agent resistant derivative AII, was investigated by uptake of [ 3 H]NAD by permeabilised cells into acid-precipitable material that was sensitive to phosphodiesterase but insensitive to DNase and RNase. Basal activities in both lymphoma lines were 3-4-fold greater than in mouse L1210 leukaemia cells. However, total endogenous poly (ADP-R) polymerase activity in both L5178Y cell lines, stimulated by a large excess of DNase in the presence of Triton X-100, was less than half the activity in L1210 cells. Doses of N-methyl-N-nitrosourea (MNU) that produced 20-50% survival of colony-forming units increased poly (ADP-R) in both lymphoma lines by only 25% compared with 377% in L1210 cells when synthesis was measured immediately after a 30-min exposure of MNU. Concentrations of 3-aminobenzamide (3AB) above 2.5 mM inhibited colony-forming ability of lymphoma cells and equally inhibited uptake of [ 14 C]formate into protein, RNA and DNA indicating that 3AB behaves as a general metabolic poison. Non-toxic concentrations of 3AB potentiated cell killing by MNU to a similar degree in both lymphoma cell lines. In conclusion, the authors have found little evidence to support the hypothesis that the differential sensitivity of LS and AII is related to poly ADP-ribosylation. Compared with other mouse cells, L5178Y cells appear deficient in poly (ADP-R) polymerase and poly (ADP-R) glycohydrolase activities

  14. Colony Dimorphism in Bradyrhizobium Strains

    Science.gov (United States)

    Sylvester-Bradley, Rosemary; Thornton, Philip; Jones, Peter

    1988-01-01

    Ten isolates of Bradyrhizobium spp. which form two colony types were studied; the isolates originated from a range of legume species. The two colony types differed in the amount of gum formed or size or both, depending on the strain. Whole 7-day-old colonies of each type were subcultured to determine the proportion of cells which had changed to the other type. An iterative computerized procedure was used to determine the rate of switching per generation between the two types and to predict proportions reached at equilibrium for each strain. The predicted proportions of the wetter (more gummy) or larger colony type at equilibrium differed significantly between strains, ranging from 0.9999 (strain CIAT 2383) to 0.0216 (strain CIAT 2469), because some strains switched faster from dry to wet (or small to large) and others switched faster from wet to dry (or large to small). Predicted equilibrium was reached after about 140 generations in strain USDA 76. In all but one strain (CIAT 3030) the growth rate of the wetter colony type was greater than or similar to that of the drier type. The mean difference in generation time between the two colony types was 0.37 h. Doubling times calculated for either colony type after 7 days of growth on the agar surface ranged from 6.0 to 7.3 h. The formation of two persistent colony types by one strain (clonal or colony dimorphism) may be a common phenomenon among Bradyrhizobium strains. Images PMID:16347599

  15. FORMING SELF-ASSEMBLED CELL ARRAYS AND MEASURING THE OXYGEN CONSUMPTION RATE OF A SINGLE LIVE CELL.

    Science.gov (United States)

    Etzkorn, James R; McQuaide, Sarah C; Anderson, Judy B; Meldrum, Deirdre R; Parviz, Babak A

    2009-06-01

    We report a method for forming arrays of live single cells on a chip using polymer micro-traps made of SU8. We have studied the toxicity of the microfabricated structures and the associated environment for two cell lines. We also report a method for measuring the oxygen consumption rate of a single cell using optical interrogation of molecular oxygen sensors placed in micromachined micro-wells by temporarily sealing the cells in the micro-traps. The new techniques presented here add to the collection of tools available for performing "single-cell" biology. A single-cell self-assembly yield of 61% was achieved with oxygen draw down rates of 0.83, 0.82, and 0.71 fmol/minute on three isolated live A549 cells.

  16. Human Adipose Derived Stem Cells Induced Cell Apoptosis and S Phase Arrest in Bladder Tumor

    Directory of Open Access Journals (Sweden)

    Xi Yu

    2015-01-01

    Full Text Available The aim of this study was to determine the effect of human adipose derived stem cells (ADSCs on the viability and apoptosis of human bladder cancer cells. EJ and T24 cells were cocultured with ADSCs or cultured with conditioned medium of ADSCs (ADSC-CM, respectively. The cell counting and colony formation assay showed ADSCs inhibited the proliferation of EJ and T24 cells. Cell viability assessment revealed that the secretions of ADSCs, in the form of conditioned medium, were able to decrease cancer cell viability. Wound-healing assay suggested ADSC-CM suppressed migration of T24 and EJ cells. Moreover, the results of the flow cytometry indicated that ADSC-CM was capable of inducing apoptosis of T24 cells and inducing S phase cell cycle arrest. Western blot revealed ADSC-CM increased the expression of cleaved caspase-3 and cleaved PARP, indicating that ADSC-CM induced apoptosis in a caspase-dependent way. PTEN/PI3K/Akt pathway and Bcl-2 family proteins were involved in the mechanism of this reaction. Our study indicated that ADSCs may provide a promising and practicable manner for bladder tumor therapy.

  17. Putative porcine embryonic stem cell lines derived from aggregated four-celled cloned embryos produced by oocyte bisection cloning.

    Science.gov (United States)

    Siriboon, Chawalit; Lin, Yu-Hsuan; Kere, Michel; Chen, Chun-Da; Chen, Lih-Ren; Chen, Chien-Hong; Tu, Ching-Fu; Lo, Neng-Wen; Ju, Jyh-Cherng

    2015-01-01

    We attempted to isolate ES cell lines using inner cell masses from high-quality cloned porcine blastocysts. After being seeded onto feeders, embryos had better (P cloned embryos (62.8, 42.6 and 12.8% vs. 76.2, 55.2 and 26.2%, respectively) compared to the non-aggregated group (41.6, 23.4 and 3.9%). Effects of feeder types (STO vs. MEF) and serum sources (FBS vs. KSR) on extraction of cloned embryo-derived porcine ES cells were examined. More (17.1%) ntES cell lines over Passage 3 were generated in the MEF/KSR group. However, ntES cells cultured in KSR-supplemented medium had a low proliferation rate with defective morphology, and eventually underwent differentiation or apoptosis subsequently. Approximately 26.1, 22.7 and 35.7% of primary colonies were formed after plating embryos in DMEM, DMEM/F12 and α-MEM media, respectively. Survival rates of ntES cells cultured in α-MEM, DMEM and DMEM/F12 were 16.7, 4.3 and 6.8%, respectively (P > 0.05). We further examined the beneficial effect of TSA treatment of 3× aggregated cloned embryos on establishment of ntES cell lines. Primary colony numbers and survival rates of ntES cells beyond passage 3 were higher (P cells, remaining undifferentiated over 25 passages, had alkaline phosphatase activity and expressed ES specific markers Oct4, Nanog, Sox2, and Rex01. Moreover, these ntES cells successfully differentiated into embryoid bodies (EBs) that expressed specific genes of all three germ layers after being cultured in LIF-free medium. In conclusion, we have successfully derived putative porcine ntES cells with high efficiency from quality cloned embryos produced by embryo aggregation, and optimized the ES cell culture system suitable for establishing and maintaining ntES cell lines in undifferentiated state.

  18. Nutrient Shielding in Clusters of Cells

    Science.gov (United States)

    Lavrentovich, Maxim O.; Koschwanez, John H.; Nelson, David R.

    2014-01-01

    Cellular nutrient consumption is influenced by both the nutrient uptake kinetics of an individual cell and the cells’ spatial arrangement. Large cell clusters or colonies have inhibited growth at the cluster's center due to the shielding of nutrients by the cells closer to the surface. We develop an effective medium theory that predicts a thickness ℓ of the outer shell of cells in the cluster that receives enough nutrient to grow. The cells are treated as partially absorbing identical spherical nutrient sinks, and we identify a dimensionless parameter ν that characterizes the absorption strength of each cell. The parameter ν can vary over many orders of magnitude between different cell types, ranging from bacteria and yeast to human tissue. The thickness ℓ decreases with increasing ν, increasing cell volume fraction ϕ, and decreasing ambient nutrient concentration ψ∞. The theoretical results are compared with numerical simulations and experiments. In the latter studies, colonies of budding yeast, Saccharomyces cerevisiae, are grown on glucose media and imaged under a confocal microscope. We measure the growth inside the colonies via a fluorescent protein reporter and compare the experimental and theoretical results for the thickness ℓ. PMID:23848711

  19. Role of non-canonical Beclin 1-independent autophagy in cell death induced by resveratrol in human breast cancer cells.

    Science.gov (United States)

    Scarlatti, F; Maffei, R; Beau, I; Codogno, P; Ghidoni, R

    2008-08-01

    Resveratrol, a polyphenol found in grapes and other fruit and vegetables, is a powerful chemopreventive and chemotherapeutic molecule potentially of interest for the treatment of breast cancer. The human breast cancer cell line MCF-7, which is devoid of caspase-3 activity, is refractory to apoptotic cell death after incubation with resveratrol. Here we show that resveratrol arrests cell proliferation, triggers death and decreases the number of colonies of cells that are sensitive to caspase-3-dependent apoptosis (MCF-7 casp-3) and also those that are unresponsive to it (MCF-7vc). We demonstrate that resveratrol (i) acts via multiple pathways to trigger cell death, (ii) induces caspase-dependent and caspase-independent cell death in MCF-7 casp-3 cells, (iii) induces only caspase-independent cell death in MCF-7vc cells and (iv) stimulates macroautophagy. Using BECN1 and hVPS34 (human vacuolar protein sorting 34) small interfering RNAs, we demonstrate that resveratrol activates Beclin 1-independent autophagy in both cell lines, whereas cell death via this uncommon form of autophagy occurs only in MCF-7vc cells. We also show that this variant form of autophagic cell death is blocked by the expression of caspase-3, but not by its enzymatic activity. In conclusion, this study reveals that non-canonical autophagy induced by resveratrol can act as a caspase-independent cell death mechanism in breast cancer cells.

  20. A Simple and Robust Method for Culturing Human-Induced Pluripotent Stem Cells in an Undifferentiated State Using Botulinum Hemagglutinin.

    Science.gov (United States)

    Kim, Mee-Hae; Matsubara, Yoshifumi; Fujinaga, Yukako; Kino-Oka, Masahiro

    2018-02-01

    Clinical and industrial applications of human-induced pluripotent stem cells (hiPSCs) is hindered by the lack of robust culture strategies capable of sustaining a culture in an undifferentiated state. Here, a simple and robust hiPSC-culture-propagation strategy incorporating botulinum hemagglutinin (HA)-mediated selective removal of cells deviating from an undifferentiated state is developed. After HA treatment, cell-cell adhesion is disrupted, and deviated cells detached from the central region of the colony to subsequently form tight monolayer colonies following prolonged incubation. The authors find that the temporal and dose-dependent activity of HA regulated deviated-cell removal and recoverability after disruption of cell-cell adhesion in hiPSC colonies. The effects of HA are confirmed under all culture conditions examined, regardless of hiPSC line and feeder-dependent or -free culture conditions. After routine application of our HA-treatment paradigm for serial passages, hiPSCs maintains expression of pluripotent markers and readily forms embryoid bodies expressing markers for all three germ-cell layers. This method enables highly efficient culturing of hiPSCs and use of entire undifferentiated portions without having to pick deviated cells manually. This simple and readily reproducible culture strategy is a potentially useful tool for improving the robust and scalable maintenance of undifferentiated hiPSC cultures. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Effects of Electromagnetic Stimulation on Cell Density and Neural Markers in Murine Enteric Cell Cultures

    International Nuclear Information System (INIS)

    Carreon-Rodriguez, A.; Belkind-Gerson, J.; Serrano-Luna, G.; Canedo-Dorantes, L.

    2008-01-01

    Availability of adult stem cells from several organs like bone marrow, umbilical cord blood or peripheral blood has become a powerful therapeutic tool for many chronic diseases. Potential of adult stem cells for regeneration extents to other tissues among them the nervous system. However two obstacles should be resolved before such cells could be currently applied in clinical practice: a) slow growth rate and b) ability to form enough dense colonies in order to populate a specific injury or cellular deficiency. Many approaches have been explored as genetic differentiation programs, growth factors, and supplemented culture media, among others. Electromagnetic field stimulation of differentiation, proliferation, migration, and particularly on neurogenesis is little known. Since the biological effects of ELF-EMF are well documented, we hypothesize ELF-EMF could affect growth and maturation of stem cells derived of enteric tissue

  2. Derivation and characterization of a pig embryonic stem cell-derived exocrine pancreatic cell line

    Science.gov (United States)

    The establishment and initial characterization of a pig embryonic stem cell-derived pancreatic cell line, PICM-31, and a colony-cloned derivative cell line, PICM-31A, is described. The cell lines were propagated for several months at split ratios of 1:3 or 1:5 at each passage on STO feeder cells af...

  3. Reprogramming of cell junction modules during stepwise epithelial to mesenchymal transition and accumulation of malignant features in vitro in a prostate cell model

    International Nuclear Information System (INIS)

    Ke, Xi-song; Li, Wen-cheng; Hovland, Randi; Qu, Yi; Liu, Run-hui; McCormack, Emmet; Thorsen, Frits; Olsen, Jan Roger; Molven, Anders; Kogan-Sakin, Ira; Rotter, Varda; Akslen, Lars A.; Oyan, Anne Margrete; Kalland, Karl-Henning

    2011-01-01

    Epithelial to mesenchymal transition (EMT) is pivotal in tumor metastasis. Our previous work reported an EMT model based on primary prostate epithelial cells (EP156T) which gave rise to cells with mesenchymal phenotype (EPT1) without malignant transformation. To promote prostate cell transformation, cells were maintained in saturation density cultures to select for cells overriding quiescence. Foci formed repeatedly following around 8 weeks in confluent EPT1 monolayers. Only later passage EPT1, but not EP156T cells of any passage, could form foci. Cells isolated from the foci were named EPT2 and formed robust colonies in soft agar, a malignant feature present neither in EP156T nor in EPT1 cells. EPT2 cells showed additional malignant traits in vitro, including higher ability to proliferate following confluence, higher resistance to apoptosis and lower dependence on exogenous growth factors than EP156T and EPT1 cells. Microarray profiling identified gene sets, many of which belong to cell junction modules, that changed expression from EP156T to EPT1 cells and continued to change from EPT1 to EPT2 cells. Our findings provide a novel stepwise cell culture model in which EMT emerges independently of transformation and is associated with subsequent accumulation of malignant features in prostate cells. Reprogramming of cell junction modules is involved in both steps.

  4. Generation of stratified squamous epithelial progenitor cells from mouse induced pluripotent stem cells.

    Directory of Open Access Journals (Sweden)

    Satoru Yoshida

    Full Text Available BACKGROUND: Application of induced pluripotent stem (iPS cells in regenerative medicine will bypass ethical issues associated with use of embryonic stem cells. In addition, patient-specific IPS cells can be useful to elucidate the pathophysiology of genetic disorders, drug screening, and tailor-made medicine. However, in order to apply iPS cells to mitotic tissue, induction of tissue stem cells that give rise to progeny of the target organ is required. METHODOLOGY/PRINCIPAL FINDINGS: We induced stratified epithelial cells from mouse iPS cells by co-culture with PA6 feeder cells (SDIA-method with use of BMP4. Clusters of cells positive for the differentiation markers KRT1 or KRT12 were observed in KRT14-positive colonies. We successfully cloned KRT14 and p63 double-positive stratified epithelial progenitor cells from iPS-derived epithelial cells, which formed stratified epithelial sheets consisting of five- to six-polarized epithelial cells in vitro. When these clonal cells were cultured on denuded mouse corneas, a robust stratified epithelial layer was observed with physiological cell polarity including high levels of E-cadherin, p63 and K15 expression in the basal layer and ZO-1 in the superficial layer, recapitulating the apico-basal polarity of the epithelium in vivo. CONCLUSIONS/SIGNIFICANCE: These results suggest that KRT14 and p63 double-positive epithelial progenitor cells can be cloned from iPS cells in order to produce polarized multilayer epithelial cell sheets.

  5. Colony formation in agar: in vitro assay for haemopoietic stem cells

    NARCIS (Netherlands)

    Dicke, K.A.; Platenburg, M.G.C.; Bekkum, D.W. van

    1971-01-01

    Using a method in which embryo fibroblasts were used as feeder layers, the colony forming capacity in agar of a variety of mouse haemopoietic suspensions was compared with their CFUs content. A striking parallelism between the results of the two assays was found. In addition, under certain

  6. Effect of interleukin-9 on clonogenic maturation and cell-cycle status of fetal and adult hematopoietic progenitors

    Energy Technology Data Exchange (ETDEWEB)

    Holbrook, S.T.; Ohls, R.K.; Schibler, K.R.; Yang, Y.C.; Christensen, R.D. (Univ. of Utah School of Medicine, Salt Lake City (USA))

    1991-05-15

    We assessed the effect of interleukin-9 (IL-9) on clonogenic maturation and cell-cycle status of hematopoietic progenitors of fetal (umbilical cord blood) and adult (bone marrow) origin. As a single agent IL-9 supported, in a concentration-dependent fashion, maturation of burst-forming units-erythroid (BFU-E) of adult and fetal origin. However, only 1/3 the number of adult BFU-E colonies developed, as did in response to granulocyte-macrophage colony-stimulating factor (GM-CSF), and only 1/6 the number developed as did in response to IL-3. In contrast, the effect of IL-9 on fetal BFU-E colonies was equal to that of GM-CSF and IL-3. Synergistic effects of IL-9 with low concentrations (0.1 ng/mL) of GM-CSF and IL-3 were seen on adult BFU-E colony formation, but no effect was apparent at higher concentrations (1.0 ng/mL). In contrast, using fetal cells, synergistic effects of IL-9 with low and high concentrations of GM-CSF and IL-3 were apparent. Addition of IL-9 to plates containing fetal cells plus GM-CSF and IL-3 not only resulted in more BFU-E colonies, but also in more multicentered (greater than or equal to 10 individual centers) colonies, and more cells per colony. IL-9 had a wider spectrum of action on progenitors of fetal origin than on progenitors of adult origin, supporting the generation of fetal multipotent colony-forming unit (CFU)-Mix and CFU-GM colonies. Incubation with IL-9 did not accelerate cycling of adult or fetal BFU-E, CFU-Mix, or CFU-GM to the extent observed after incubation with IL-6.

  7. Effect of interleukin-9 on clonogenic maturation and cell-cycle status of fetal and adult hematopoietic progenitors

    International Nuclear Information System (INIS)

    Holbrook, S.T.; Ohls, R.K.; Schibler, K.R.; Yang, Y.C.; Christensen, R.D.

    1991-01-01

    We assessed the effect of interleukin-9 (IL-9) on clonogenic maturation and cell-cycle status of hematopoietic progenitors of fetal (umbilical cord blood) and adult (bone marrow) origin. As a single agent IL-9 supported, in a concentration-dependent fashion, maturation of burst-forming units-erythroid (BFU-E) of adult and fetal origin. However, only 1/3 the number of adult BFU-E colonies developed, as did in response to granulocyte-macrophage colony-stimulating factor (GM-CSF), and only 1/6 the number developed as did in response to IL-3. In contrast, the effect of IL-9 on fetal BFU-E colonies was equal to that of GM-CSF and IL-3. Synergistic effects of IL-9 with low concentrations (0.1 ng/mL) of GM-CSF and IL-3 were seen on adult BFU-E colony formation, but no effect was apparent at higher concentrations (1.0 ng/mL). In contrast, using fetal cells, synergistic effects of IL-9 with low and high concentrations of GM-CSF and IL-3 were apparent. Addition of IL-9 to plates containing fetal cells plus GM-CSF and IL-3 not only resulted in more BFU-E colonies, but also in more multicentered (greater than or equal to 10 individual centers) colonies, and more cells per colony. IL-9 had a wider spectrum of action on progenitors of fetal origin than on progenitors of adult origin, supporting the generation of fetal multipotent colony-forming unit (CFU)-Mix and CFU-GM colonies. Incubation with IL-9 did not accelerate cycling of adult or fetal BFU-E, CFU-Mix, or CFU-GM to the extent observed after incubation with IL-6

  8. The separation of a mixture of bone marrow stem cells from tumor cells: an essential step for autologous bone marrow transplantation

    International Nuclear Information System (INIS)

    Rubin, P.; Wheeler, K.T.; Keng, P.C.; Gregory, P.K.; Croizat, H.

    1981-01-01

    KHT tumor cells were mixed with mouse bone marrow to simulate a sample of bone marrow containing metastatic tumor cells. This mixture was separated into a bone marrow fraction and a tumor cell fraction by centrifugal elutriation. Elutriation did not change the transplantability of the bone marrow stem cells as measured by a spleen colony assay and an in vitro erythroid burst forming unit assay. The tumorogenicity of the KHT cells was similarly unaffected by elutriation. The data showed that bone marrow cells could be purified to less than 1 tumor cell in more than 10 6 bone marrow cells. Therefore, purification of bone marrow removed prior to lethal radiation-drug combined therapy for subsequent autologous transplantation appears to be feasible using modifications of this method if similar physical differences between human metastatic tumor cells and human bone marrow cells exist. This possibility is presently being explored

  9. STAT3 signaling pathway is necessary for cell survival and tumorsphere forming capacity in ALDH+/CD133+ stem cell-like human colon cancer cells

    International Nuclear Information System (INIS)

    Lin, Li; Fuchs, James; Li, Chenglong; Olson, Veronica; Bekaii-Saab, Tanios; Lin, Jiayuh

    2011-01-01

    Highlights: ► The phosphorylated or activated form of STAT3 was expressed in colon cancer stem-like cells. ► STAT3 inhibitor, FLLL32 inhibits P-STAT3 and STAT3 target genes in colon cancer stem-like cells. ► Inhibition of STAT3 resulted in decreased cell viability and reduced numbers of tumorspheres. ► STAT3 is required for survival and tumorsphere forming capacity in colon cancer stem-like cells. ► Targeting STAT3 in cancer stem-like cells may offer a novel treatment approach for colon cancer. -- Abstract: Persistent activation of Signal Transducers and Activators of Transcription 3 (STAT3) is frequently detected in colon cancer. Increasing evidence suggests the existence of a small population of colon cancer stem or cancer-initiating cells may be responsible for tumor initiation, metastasis, and resistance to chemotherapy and radiation. Whether STAT3 plays a role in colon cancer-initiating cells and the effect of STAT3 inhibition is still unknown. Flow cytometry was used to isolate colon cancer stem-like cells from three independent human colon cancer cell lines characterized by both aldehyde dehydrogenase (ALDH)-positive and CD133-positive subpopulation (ALDH + /CD133 + ). The effects of STAT3 inhibition in colon cancer stem-like cells were examined. The phosphorylated or activated form of STAT3 was expressed in colon cancer stem-like cells and was reduced by a STAT3-selective small molecular inhibitor, FLLL32. FLLL32 also inhibited the expression of potential STAT3 downstream target genes in colon cancer stem-like cells including survivin, Bcl-XL, as well as Notch-1, -3, and -4, which may be involved in stem cell function. Furthermore, FLLL32 inhibited cell viability and tumorsphere formation as well as induced cleaved caspase-3 in colon cancer stem-like cells. FLLL32 is more potent than curcumin as evidenced with lower IC50 in colon cancer stem-like cells. In summary, our results indicate that STAT3 is a novel therapeutic target in colon cancer stem

  10. In vitro Rb-1 gene transfer to retinoblastoma cell lines

    International Nuclear Information System (INIS)

    Choi, Sang Wook; Ham, Yong Hoh; Kim, Mee Heui

    1994-04-01

    After transfection of Rb-vector to packaging cell line (CRIP) by Ca-P precipitation method, we could select nineteen colonies of G-418 resistant clone by ring cloning. Each colony was transduced to NIH3T3 cells to select the one which produces high titer virus. After NIH3T3 cells transduction, we could get 28 colony counts for the high, 127 for the middle, and 6 for the low viral titer. With the supernatant of the high viral titer colony (CRIPRb 2-5). We transduct retinoblastoma cell lines. 5 figs, 11 refs. (Author)

  11. Natural Killer Cells Improve Hematopoietic Stem Cell Engraftment by Increasing Stem Cell Clonogenicity In Vitro and in a Humanized Mouse Model.

    Science.gov (United States)

    Escobedo-Cousin, Michelle; Jackson, Nicola; Laza-Briviesca, Raquel; Ariza-McNaughton, Linda; Luevano, Martha; Derniame, Sophie; Querol, Sergio; Blundell, Michael; Thrasher, Adrian; Soria, Bernat; Cooper, Nichola; Bonnet, Dominique; Madrigal, Alejandro; Saudemont, Aurore

    2015-01-01

    Cord blood (CB) is increasingly used as a source of hematopoietic stem cells (HSC) for transplantation. Low incidence and severity of graft-versus-host disease (GvHD) and a robust graft-versus-leukemia (GvL) effect are observed following CB transplantation (CBT). However, its main disadvantages are a limited number of HSC per unit, delayed immune reconstitution and a higher incidence of infection. Unmanipulated grafts contain accessory cells that may facilitate HSC engraftment. Therefore, the effects of accessory cells, particularly natural killer (NK) cells, on human CB HSC (CBSC) functions were assessed in vitro and in vivo. CBSC cultured with autologous CB NK cells showed higher levels of CXCR4 expression, a higher migration index and a higher number of colony forming units (CFU) after short-term and long-term cultures. We found that CBSC secreted CXCL9 following interaction with CB NK cells. In addition, recombinant CXCL9 increased CBSC clonogenicity, recapitulating the effect observed of CB NK cells on CBSC. Moreover, the co-infusion of CBSC with CB NK cells led to a higher level of CBSC engraftment in NSG mouse model. The results presented in this work offer the basis for an alternative approach to enhance HSC engraftment that could improve the outcome of CBT.

  12. Effect of granulocyte colony-stimulating factor (G-CSF) in human immunodeficiency virus-infected patients: increase in numbers of naive CD4 cells and CD34 cells makes G-CSF a candidate for use in gene therapy or to support antiretroviral therapy

    DEFF Research Database (Denmark)

    Nielsen, S D; Afzelius, P; Dam-Larsen, S

    1998-01-01

    The potential of granulocyte colony-stimulating factor (G-CSF) to mobilize CD4 cells and/or CD34 cells for use in gene therapy or to support antiretroviral therapy was examined. Ten human immunodeficiency virus-infected patients were treated with G-CSF (300 microg/day) for 5 days. Numbers of CD4.......01/microL (P CSF induced increases in numbers of CD34 cells and CD4 cells in HIV-infected patients...

  13. An evaluation of the choice of feeder cell growth arrest for the production of cultured epidermis.

    Science.gov (United States)

    Chugh, Rishi Man; Chaturvedi, Madhusudan; Yerneni, Lakshmana Kumar

    2015-12-01

    Growth arrested 3T3 cells have been used as feeder cells in human epidermal keratinocyte cultures to produce cultured epidermal autografts for the treatment of burns. The feeder cells were ideally growth-arrested by gamma-irradiation. Alternatively, growth arrest by mitomycin C treatment is a cost effective option. We compared the functional efficacy of these two approaches in keratinocyte cultures by colony forming efficiency, the net growth area of colonies, BrdU labeling and histological features of cultured epidermal sheets. The growth area estimation involved a semi-automated digital technique using the Adobe Photoshop and comprised of isolation and enumeration of red pixels in Rhodamine B-stained keratinocyte colonies. A further refinement of the technique led to the identification of critical steps to increasing the degree of accuracy and enabling its application as an extension of colony formation assay. The results on feeder cell functionality revealed that the gamma irradiated feeders influenced significantly higher colony forming efficiency and larger growth area than the mitomycin C treated feeders. The BrdU labeling study indicated significant stimulation of the overall keratinocyte proliferation by the gamma irradiated feeders. The cultured epidermal sheets produced by gamma feeders were relatively thicker than those produced by mitomycin C feeders. We discussed the clinical utility of mitomycin C feeders from the viewpoint of cost-effective burn care in developing countries. Copyright © 2015 Elsevier Ltd and ISBI. All rights reserved.

  14. Modulation of cell adhesion and viability of cultured murine bone marrow cells by arsenobetaine, a major organic arsenic compound in marine animals.

    Science.gov (United States)

    Sakurai, T; Fujiwara, K

    2001-01-01

    1. In this study, we investigated the biological effects of trimethyl (carboxymethyl) arsonium zwitterion, namely arsenobetaine (AsBe), which is a major organic arsenic compound in marine animals using murine bone marrow (BM) cells and compared them with those of an inorganic arsenical, sodium arsenite, in vitro. 2. Sodium arsenite showed strong cytotoxicity in BM cells, and its IC(50) was 6 microM. In contrast, AsBe significantly enhanced the viability of BM cells in a dose-dependent manner during a 72-h incubation; about a twofold increase in the viability of cells compared with that of control cells cultured with the medium alone was observed with a microM level of AsBe. 3. In morphological investigations, AsBe enhanced the numbers of large mature adherent cells, especially granulocytes, during a 72-h BM culture. When BM cells were cultured together with AsBe and a low dose (1 u ml(-1)) of recombinant murine granulocyte/macrophage colony-stimulating factor (rMu GM-CSF), significant additive-like increasing effects were observed on the numbers of both granulocytes and macrophages originated from BM cells. However, AsBe did not cause proliferation of BM cells at all as determined by colony-forming assay using a gelatinous medium. 4. These findings demonstrate the unique and potent biological effects in mammalian cells of AsBe, a major organic arsenic compound in various marine animals which are ingested daily as seafood in many countries.

  15. Models relevant to radiation effects on stem cell pools

    Energy Technology Data Exchange (ETDEWEB)

    Lajtha, L G

    1971-04-01

    The available evidence clearly indicates the existence of a pluripotential primitive stem cell population (CFU). In the normal animal a large proportion of this population will 'sit' in the G{sub 0} state. At any time a small proportion of these cells will differentiate into one or more 'precursor' populations. One such precursor population is the erythropoietin responsive cell (ERC) and it is important to realize that this population has a significant number of mitoses in it, i.e. it is capable of considerable, although not indefinite proliferation. This is indicated by the colony growth during which, from a single colony former, large numbers of differentiated cells can be formed, in excess of several millions, at a time when the CFU numbers in the colony are still very small. To understand then the effects of radiation on this complex series of populations the following will have to be borne in mind. The ultimate stem cells are, at least in the small rodent, the CFU. It is their quantity that is essential for regeneration. However, the normal rate of differentiation of CFU in the small rodent is very low. This is because this rate of differentiation gives rise to a possibly committed precursor cell population such as the ERC, or possibly the agar forming 'GRC', the precursor populations with considerable proliferative potential in them. Therefore, after relatively small doses of radiation, or even during a regime of continuous irradiation, the proliferative potential of these transit precursor populations will be able to cope with near normal haemopoiesis at a time when the number of colony formers is gradually depleted. It is also significant that the rate of seeding of the primitive colony former is not related to its numbers and, therefore, under conditions of partial irradiation, at least in the small rodent, greatly increased relative migration and to some extent increased absolute migration of the CFU is possible, with consequent enhancement of the

  16. Mechanical Properties of Human Cells Change during Neoplastic Processes

    Science.gov (United States)

    Guthold, Martin; Guo, Xinyi; Bonin, Keith; Scarpinato, Karin

    2014-03-01

    Using an AFM with a spherical probe of 5.3 μm, we determined mechanical properties of individual human mammary epithelial cells that have progressed through four stages of neoplastic transformation: normal, immortal, tumorigenic, and metastatic. Measurements on cells in all four stages were taken over both the nucleus and the cytoplasm. Moreover, the measurements were made for cells outside of a colony (isolated), on the periphery of a colony, and inside a colony. By fitting the AFM force vs. indentation curves to a Hertz model, we determined the Young's modulus, E. We found a distinct contrast in the influence a cell's colony environment has on its stiffness depending on whether the cells are normal or cancer cells. We also found that cells become softer as they advance to the tumorigenic stage and then stiffen somewhat in the final step to metastatic cells. For cells averaged over all locations the stiffness values of the nuclear region for normal, immortal, tumorigenic, and metastatic cells were (mean +/- sem) 880 +/- 50, 940+/-50, 400 +/- 20, and 600 +/-20 Pa respectively. Cytoplasmic regions followed a similar trend. These results point to a complex picture of the mechanical changes that occur as cells undergo neoplastic transformation. This work is supported by NSF Materials and Surface Engineering grant CMMI-1152781.

  17. The Fate of a Normal Human Cell Traversed by a Single Charged Particle

    Science.gov (United States)

    Fournier, C.; Zahnreich, S.; Kraft, D.; Friedrich, T.; Voss, K.-O.; Durante, M.; Ritter, S.

    2012-01-01

    The long-term “fate” of normal human cells after single hits of charged particles is one of the oldest unsolved issues in radiation protection and cellular radiobiology. Using a high-precision heavy-ion microbeam we could target normal human fibroblasts with exactly one or five carbon ions and measured the early cytogenetic damage and the late behaviour using single-cell cloning. Around 70% of the first cycle cells presented visible aberrations in mFISH after a single ion traversal, and about 5% of the cells were still able to form colonies. In one third of selected high-proliferative colonies we observed clonal (radiation-induced) aberrations. Terminal differentiation and markers of senescence (PCNA, p16) in the descendants of cells traversed by one carbon ion occurred earlier than in controls, but no evidence of radiation-induced chromosomal instability was found. We conclude that cells surviving single-ion traversal, often carrying clonal chromosome aberrations, undergo accelerated senescence but maintain chromosomal stability. PMID:22966418

  18. Polo-like kinase 1 (PLK1) inhibition suppresses cell growth and enhances radiation sensitivity in medulloblastoma cells

    International Nuclear Information System (INIS)

    Harris, Peter S; Foreman, Nicholas K; Vibhakar, Rajeev; Venkataraman, Sujatha; Alimova, Irina; Birks, Diane K; Donson, Andrew M; Knipstein, Jeffrey; Dubuc, Adrian; Taylor, Michael D; Handler, Michael H

    2012-01-01

    Medulloblastoma is the most common malignant brain tumor in children and remains a therapeutic challenge due to its significant therapy-related morbidity. Polo-like kinase 1 (PLK1) is highly expressed in many cancers and regulates critical steps in mitotic progression. Recent studies suggest that targeting PLK1 with small molecule inhibitors is a promising approach to tumor therapy. We examined the expression of PLK1 mRNA in medulloblastoma tumor samples using microarray analysis. The impact of PLK1 on cell proliferation was evaluated by depleting expression with RNA interference (RNAi) or by inhibiting function with the small molecule inhibitor BI 2536. Colony formation studies were performed to examine the impact of BI 2536 on medulloblastoma cell radiosensitivity. In addition, the impact of depleting PLK1 mRNA on tumor-initiating cells was evaluated using tumor sphere assays. Analysis of gene expression in two independent cohorts revealed that PLK1 mRNA is overexpressed in some, but not all, medulloblastoma patient samples when compared to normal cerebellum. Inhibition of PLK1 by RNAi significantly decreased medulloblastoma cell proliferation and clonogenic potential and increased cell apoptosis. Similarly, a low nanomolar concentration of BI 2536, a small molecule inhibitor of PLK1, potently inhibited cell growth, strongly suppressed the colony-forming ability, and increased cellular apoptosis of medulloblastoma cells. Furthermore, BI 2536 pretreatment sensitized medulloblastoma cells to ionizing radiation. Inhibition of PLK1 impaired tumor sphere formation of medulloblastoma cells and decreased the expression of SRY (sex determining region Y)-box 2 (SOX2) mRNA in tumor spheres indicating a possible role in targeting tumor inititiating cells. Our data suggest that targeting PLK1 with small molecule inhibitors, in combination with radiation therapy, is a novel strategy in the treatment of medulloblastoma that warrants further investigation

  19. Primary radiation damage and disturbance in cell divisions

    International Nuclear Information System (INIS)

    Kim, Jin Kyu; Lee, Yun-Jong; Kim, Jae-Hun; Petin, Vladislav G.; Nili, Mohammad

    2008-01-01

    Survived cells from a homogeneous population exposed to ionizing radiation form various colonies of different sizes and morphology on a solid nutrient medium, which appear at different time intervals after irradiation. Such a phenomenon agrees well with the modern theory of microdosimetry and classical hit-and-target models of radiobiology. According to the hit-principle, individual cells exposed to the same dose of radiation are damaged in different manners. It means that the survived cells can differ in the content of sublethal damage (hits) produced by the energy absorbed into the cell and which is not enough to give rise to effective radiation damage which is responsible for cell killing or inactivation. In diploid yeast cells, the growth rate of cells from 250 colonies of various sizes appeared at different time intervals after irradiation with 600 Gy of gamma radiation from a 60 Co isotopic source was analyzed. The survival rate after irradiation was 20%. Based on the analyses results, it was possible to categorize the clones grown from irradiated cells according to the number of sub-lesions from 1 to 4. The clones with various numbers of sub-lesions were shown to be different in their viability, radiosensitivity, sensitivity to environmental conditions, and the frequency of recombination and respiratory deficient mutations. Cells from unstable clones exhibited an enhanced radiosensitivity, and an increased portion of morphologically changed cells, nonviable cells and respiration mutants, as well. The degree of expression of the foregoing effects was higher if the number of primary sublethal lesions was greater in the originally irradiated cell. Disturbance in cell division can be characterized by cell inactivation or incorrect distribution of mitochondria between daughter cells. Thus, the suggested methodology of identification of cells with a definite number of primary sublethal lesions will promote further elucidation of the nature of primary radiation

  20. A study of chromosomal aberrations in amniotic fluid cell cultures.

    Science.gov (United States)

    Wolstenholme, J; Crocker, M; Jonasson, J

    1988-06-01

    This paper represents the analysis of 1916 routine amniotic fluid specimens harvested by an in situ fixation technique in a prospective study with regard to cultural chromosome anomalies. Excluding constitutional abnormalities, 2.9 per cent of 19,432 cells analysed showed some form of chromosome anomaly, terminal deletions (57 per cent) and chromatid/chromosome breaks and gaps (18 per cent) being the most frequent, followed by interchange aberrations (13 per cent) and trisomy (5 per cent). No case was found of more than one colony from the same culture showing the same anomaly without it being present in other cultures from the same fluid. The wholly abnormal colonies had a surplus of trisomies and from the mathematical considerations presented one may infer that these are likely to reflect the presence of abnormal cells in the amniotic fluid. Partly abnormal colonies appeared at a frequency that would correspond to virtual absence of selection against chromosomally abnormal cells when cultured in vitro. The aberrations found were similar to those seen as single cell anomalies, except for chromatid breaks and exchanges. The data suggest a basic preferential induction of trisomy for chromosomes 2, 18, 21, and the Y-chromosome. Structural aberrations showed a marked clustering of breakpoints around the centromeres. The frequency of mutant cells was low (1.4 X 10(-3)) before culture was initiated. At harvest, the frequency of abnormal cells was much higher (3 X 10(-2)) corresponding to 3 X 10(-3) mutations per cell per generation accumulating over approximately ten generations in vitro.

  1. Effect of cell cycle stage, dose rate and repair of sublethal damage of radiation-induced apoptosis in F9 teratocarcinoma cells

    International Nuclear Information System (INIS)

    Langley, R.E.; Quartuccio, S.G.; Kennealey, P.T.

    1995-01-01

    There are at least two different models of cell death after treatment with ionizing radiation. The first is a failure to undergo sustained cell division despite metabolic survival, and we refer to this end point as open-quotes classical reproductive cell death.close quotes The second is a process that results in loss of cell integrity. This second category includes cellular necrosis as well as apoptosis. Earlier studies in our laboratory showed that the predominant mechanism of cell death for irradiated F9 cell is apoptosis, and there is no indication that these cells die by necrosis. We have therefore used cells of this cell line to reassess basic radiobiological principles with respect to apoptosis. Classical reproductive cell death was determined by staining colonies derived from irradiated cells and scoring colonies of less than 50 cells as reproductively dead and colonies of more than 50 cells as survivors. Cells that failed to produce either type of colony (detached from the plate or disintegrated) were scored as having undergone apoptosis. Using these criteria we found that the fraction of the radiation-killed F9 cells that died by apoptosis did not vary when cells were irradiated at different stages of the cell cycle despite large variations in overall survival. This suggests that the factors that influence radiation sensitivity throughout the cell cycle have an equal impact on apoptosis and classical reproductive cell death. There was no difference in cell survival between split doses and single doses of X rays, suggesting that sublethal damage repair is not a factor in radiation-induced apoptosis of F9 cells. Apoptosis was not affected by changes in dose rate in the range of 0.038-4.96 Gy/min. 48 refs., 6 figs., 1 tab

  2. Differential effect of L3T4+ cells on recovery from total-body irradiation

    International Nuclear Information System (INIS)

    Pantel, K.; Nakeff, A.

    1990-01-01

    We have examined the importance of L3T4+ (murine equivalent to CD4+) cells for hematopoietic regulation in vivo in unperturbed mice and mice recovering from total-body irradiation (TBI) using a cytotoxic monoclonal antibody (MoAb) raised with the GK 1.5 hybridoma. Ablating L3T4+ cells in normal (unperturbed) B6D2F1 mice substantially decreased the S-phase fraction (determined by in vivo hydroxyurea suicide) of erythroid progenitor cells (erythroid colony-forming units, CFU-E) as compared to the pretreatment level (10% +/- 14.1% [day 3 following depletion] vs 79.8% +/- 15.9%, respectively) with a corresponding decrease in the marrow content of CFU-E at this time to approximately 1% of the pretreatment value. Although the S-phase fraction of CFU-GM was decreased to 2.2% +/- 3.1% 3 days after L3T4+ cell ablation from the 21.3% +/- 8.3% pretreatment value, CFU-GM cellularity showed little change over the 3 days following anti-L3T4 treatment. Anti-L3T4 MoAb treatment had little or no effect on either the S-phase fraction or the marrow content of hematopoietic stem cells (spleen colony-forming units, CFU-S) committed to myeloerythroid differentiation. Ablating L3T4+ cells prior to a single dose of 2 Gy TBI resulted in significantly reduced marrow contents of CFU-S on day 3 and granulocyte-macrophage colony-forming units (CFU-GM) on day 6 following TBI, with little or no effect on the corresponding recovery of CFU-E. The present findings provide the first in vivo evidence that L3T4+ cells are involved in: (1) maintaining the proliferative activity of CFU-E and CFU-GM in unperturbed mice and (2) supporting the restoration of CFU-S and CFU-GM following TBI-induced myelosuppression

  3. Mechanism of suppression of normal hemopoietic activity by lymphokine-activated killer cells and their products

    International Nuclear Information System (INIS)

    Gibson, F.M.; Malkovska, V.; Myint, A.A.; Meager, A.; Gordon-Smith, E.C.

    1991-01-01

    Interleukin 2 (IL-2)-activated lymphocytes (lymphokine-activated killer [LAK] cells) have been shown to inhibit the formation of autologous human granulocyte-macrophage hemopoietic progenitors (granulocyte-macrophage colony-forming units, CFU-GM) in vitro. Effects of LAK cells on these progenitors may include a number of different mechanisms. LAK cells are potent cytotoxic lymphocytes capable of lysing certain normal autologous cells. They also produce cytokines known to inhibit hemopoiesis (interferon gamma [IFN-gamma] and tumor necrosis factor alpha [TNF-alpha]) or enhance it (granulocyte-macrophage colony-stimulating factor, GM-CSF). In the authors' current study they analyzed the mechanism of suppression of autologous CFU-GM by LAK cells. Their results suggest that LAK cells are not directly cytotoxic to normal CFU-GM. They show that it is possible to abolish the hemopoiesis-inhibiting activity of LAK cells without abrogating their cytotoxicity against tumor cell lines using inhibitors of DNA synthesis, namely hydroxyurea or irradiation

  4. Prostate cancer cell lines under hypoxia exhibit greater stem-like properties.

    Directory of Open Access Journals (Sweden)

    Yuanyuan Ma

    Full Text Available Hypoxia is an important environmental change in many cancers. Hypoxic niches can be occupied by cancer stem/progenitor-like cells that are associated with tumor progression and resistance to radiotherapy and chemotherapy. However, it has not yet been fully elucidated how hypoxia influences the stem-like properties of prostate cancer cells. In this report, we investigated the effects of hypoxia on human prostate cancer cell lines, PC-3 and DU145. In comparison to normoxia (20% O(2, 7% O(2 induced higher expressions of HIF-1α and HIF-2α, which were associated with upregulation of Oct3/4 and Nanog; 1% O(2 induced even greater levels of these factors. The upregulated NANOG mRNA expression in hypoxia was confirmed to be predominantly retrogene NANOGP8. Similar growth rates were observed for cells cultivated under hypoxic and normoxic conditions for 48 hours; however, the colony formation assay revealed that 48 hours of hypoxic pretreatment resulted in the formation of more colonies. Treatment with 1% O(2 also extended the G(0/G(1 stage, resulting in more side population cells, and induced CD44 and ABCG2 expressions. Hypoxia also increased the number of cells positive for ABCG2 expression, which were predominantly found to be CD44(bright cells. Correspondingly, the sorted CD44(bright cells expressed higher levels of ABCG2, Oct3/4, and Nanog than CD44(dim cells, and hypoxic pretreatment significantly increased the expressions of these factors. CD44(bright cells under normoxia formed significantly more colonies and spheres compared with the CD44(dim cells, and hypoxic pretreatment even increased this effect. Our data indicate that prostate cancer cells under hypoxia possess greater stem-like properties.

  5. Role of Granulocyte-Macrophage Colony-Stimulating Factor Production by T Cells during Mycobacterium tuberculosis Infection.

    Science.gov (United States)

    Rothchild, Alissa C; Stowell, Britni; Goyal, Girija; Nunes-Alves, Cláudio; Yang, Qianting; Papavinasasundaram, Kadamba; Sassetti, Christopher M; Dranoff, Glenn; Chen, Xinchun; Lee, Jinhee; Behar, Samuel M

    2017-10-24

    Mice deficient for granulocyte-macrophage colony-stimulating factor (GM-CSF -/- ) are highly susceptible to infection with Mycobacterium tuberculosis , and clinical data have shown that anti-GM-CSF neutralizing antibodies can lead to increased susceptibility to tuberculosis in otherwise healthy people. GM-CSF activates human and murine macrophages to inhibit intracellular M. tuberculosis growth. We have previously shown that GM-CSF produced by iNKT cells inhibits growth of M. tuberculosis However, the more general role of T cell-derived GM-CSF during infection has not been defined and how GM-CSF activates macrophages to inhibit bacterial growth is unknown. Here we demonstrate that, in addition to nonconventional T cells, conventional T cells also produce GM-CSF during M. tuberculosis infection. Early during infection, nonconventional iNKT cells and γδ T cells are the main source of GM-CSF, a role subsequently assumed by conventional CD4 + T cells as the infection progresses. M. tuberculosis -specific T cells producing GM-CSF are also detected in the peripheral blood of infected people. Under conditions where nonhematopoietic production of GM-CSF is deficient, T cell production of GM-CSF is protective and required for control of M. tuberculosis infection. However, GM-CSF is not required for T cell-mediated protection in settings where GM-CSF is produced by other cell types. Finally, using an in vitro macrophage infection model, we demonstrate that GM-CSF inhibition of M. tuberculosis growth requires the expression of peroxisome proliferator-activated receptor gamma (PPARγ). Thus, we identified GM-CSF production as a novel T cell effector function. These findings suggest that a strategy augmenting T cell production of GM-CSF could enhance host resistance against M. tuberculosis IMPORTANCE Mycobacterium tuberculosis is the bacterium that causes tuberculosis, the leading cause of death by any infection worldwide. T cells are critical components of the immune

  6. Colony size distributions according to in vitro aging in human skin fibroblasts

    International Nuclear Information System (INIS)

    Kim, Jun Sang; Kim, Jae Sung; Cho, Moon June; Park, Jeong Kyu; Paik, Tae Hyun

    1999-01-01

    To investigate the percentage of colonies with 16 or more cells distribution of human skin fibroblast according to in vitro aging, and to evaluate the relationship between percentage of colonies with 16 or more cells and in vivo donor age in human skin fibroblast culture. C1, C2, C3a, and C3b human skin fibroblast samples from three breast cancer patients were used as subjects. The C1, C2, and C3a donor were 44, 54, and 55 years old, respectively. C3a and C3b cells were isolated from the same person. Single cell suspension of skin fibroblasts was prepared with primary explant technique. One hundred cells are plated into 100ml tissue culture flask and cultured for two weeks. The colony size was defined as colonies with 16 or more cells. The cultured cell was stained with crystal violet, and number of cells in each colony was determined with stereo microscope at x 10 magnification. Passage number of C1, C2, C3a and C3b skin fibroblast were 12th, 17th, and 14th, respectively. Percentage of colonies with 16 or more cells of skin fibroblast samples decreased with increasing in vitro passage number. In contrast, cumulative population doublings of skin fibroblast sample increased with increasing in vitro passage number. Percentage of colonies with 16 or more cells also decreased with increasing population doublings in human skin fibroblast culture. There was strong correlation with percentage of colonised with 16 or more cells and population doublings in C3a skin fibroblast sample. At the same point of population doublings, the percentage of colonies with 16 or more cells of the young C1 donor was higher level than the old C3a donor. The population doublings increased with increasing in vitro passage number but percentage of colonies with 16 or more cells decreased. The results of this study imply that percentage of colonies with 16 or more cells is useful as a indicator of in vitro human skin fibroblast aging and may estimate the in vivo donor age

  7. Identification of cancer stem cell markers in human malignant mesothelioma cells

    Energy Technology Data Exchange (ETDEWEB)

    Ghani, Farhana Ishrat; Yamazaki, Hiroto; Iwata, Satoshi; Okamoto, Toshihiro [Division of Clinical Immunology, Institute of Medical Science, University of Tokyo, Tokyo (Japan); Aoe, Keisuke; Okabe, Kazunori; Mimura, Yusuke [Departments of Medical Oncology, Yamaguchi-Ube Medical Center, Yamaguchi (Japan); Fujimoto, Nobukazu; Kishimoto, Takumi [Department of Respiratory Medicine, Okayama Rosai Hospital, Okayama (Japan); Yamada, Taketo [Department of Pathology, Keio University School of Medicine, Tokyo (Japan); Xu, C. Wilson [Drug Development Program, Nevada Cancer Institute, Las Vegas, NV (United States); Morimoto, Chikao, E-mail: morimoto@ims.u-tokyo.ac.jp [Division of Clinical Immunology, Institute of Medical Science, University of Tokyo, Tokyo (Japan); Drug Development Program, Nevada Cancer Institute, Las Vegas, NV (United States)

    2011-01-14

    Research highlights: {yields} We performed serial transplantation of surgical samples and established new cell lines of malignant mesothelioma. {yields} SP cell and expressions of CD9/CD24/CD26 were often observed in mesothelioma cell lines. {yields} SP and CD24{sup +} cells proliferated by asymmetric cell division-like manner. CD9{sup +} and CD24{sup +} cells have higher potential to generate spheroid colony. {yields} The marker-positive cells have clear tendency to generate larger tumors in mice. -- Abstract: Malignant mesothelioma (MM) is an aggressive and therapy-resistant neoplasm arising from the pleural mesothelial cells and usually associated with long-term asbestos exposure. Recent studies suggest that tumors contain cancer stem cells (CSCs) and their stem cell characteristics are thought to confer therapy-resistance. However, whether MM cell has any stem cell characteristics is not known. To understand the molecular basis of MM, we first performed serial transplantation of surgical samples into NOD/SCID mice and established new cell lines. Next, we performed marker analysis of the MM cell lines and found that many of them contain SP cells and expressed several putative CSC markers such as CD9, CD24, and CD26. Interestingly, expression of CD26 closely correlated with that of CD24 in some cases. Sorting and culture assay revealed that SP and CD24{sup +} cells proliferated by asymmetric cell division-like manner. In addition, CD9{sup +} and CD24{sup +} cells have higher potential to generate spheroid colony than negative cells in the stem cell medium. Moreover, these marker-positive cells have clear tendency to generate larger tumors in mouse transplantation assay. Taken together, our data suggest that SP, CD9, CD24, and CD26 are CSC markers of MM and could be used as novel therapeutic targets.

  8. Stimulation of the proliferation of hemopoietic stem cells in irradiated bone marrow cell culture

    International Nuclear Information System (INIS)

    Mori, K.J.; Izumi, H.; Seto, A.

    1981-01-01

    Long-term hemopoiesis was established in bone marrow cell culture in vitro. This culture was shown to support the recovery proliferation of hemopoietic stem cells completely in vitro after irradiation. Hemopoietic stem cells were stimulated into proliferation in culture when normal bone marrow cells were overlayed on top of the irradiated adherent cell colonies. These results indicate that proliferation and differentiation of hemopoietic stem cells in vitro are also supported by stromahemopoietic cell interactions

  9. Just-in-time rescue plerixafor in combination with chemotherapy and granulocyte-colony stimulating factor for peripheral blood progenitor cell mobilization.

    Science.gov (United States)

    Smith, Veronica R; Popat, Uday; Ciurea, Stefan; Nieto, Yago; Anderlini, Paolo; Rondon, Gabriela; Alousi, Amin; Qazilbash, Muzaffar; Kebriaei, Partow; Khouri, Issa; de Lima, Marcos; Champlin, Richard; Hosing, Chitra

    2013-09-01

    Plerixafor, a recently approved peripheral blood progenitor cell mobilizing agent, is often added to granulocyte-colony stimulating factor (G-CSF) to mobilize peripheral blood progenitor cells in patients with lymphoma or myeloma who cannot mobilize enough CD34+ cells with G-CSF alone to undergo autologous stem cell transplantation. However, data are lacking regarding the feasibility and efficacy of just-in-time plerixafor in combination with chemotherapy and G-CSF. We reviewed the peripheral blood stem cell collection data of 38 consecutive patients with lymphoma (Hodgkin's and non-Hodgkin's) and multiple myeloma who underwent chemomobilization and high-dose G-CSF and just-in-time plerixafor to evaluate the efficacy of this treatment combination. All patients with multiple myeloma and all but one patient with lymphoma collected the minimum required number of CD34+ cells to proceed with autologous stem cell transplantation (>2 × 10(6) /kg of body weight). The median CD34+ cell dose collected in patients with non-Hodgkin lymphoma was 4.93 × 10(6) /kg of body weight. The median CD34+ cell dose collected for patients with multiple myeloma was 8.81 × 10(6) /kg of body weight. Plerixafor was well tolerated; no grade 2 or higher non-hematologic toxic effects were observed. Copyright © 2013 Wiley Periodicals, Inc.

  10. Influence of dose rate on the transformation of Syrian hamster embryo cells by fission-spectrum neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Jones, C.A.; Sedita, B.A.; Hill, C.K.; Elkind, M.M.

    1988-01-01

    Several explanations for this neutron dose-rate effect have been proposed, but further investigation is necessary to determine the mechanisms involved. In all cell transformation studies to date the immortalized, aneuploid 10T1/2 cell-line has been used. These cells may be premalignant; thus their response characteristics and, in particular, the nature of the transformation event, might differ from that in a normal, fibroblast cell. One reason for the present study was to determine whether the low-dose-rate effect of fission neutrons could be demonstrated in normal cells. If so, a normal cell system, which would more closely resemble a normal in vivo system, could be used for mechanistic studies. We chose Syrian hamster embryo (SHE) fibroblasts which are normal, diploid cells with a limited life span in culture. Upon exposure to low doses of ionizing radiation, the fraction of the cells that are transformed can be identified in a standard 8--10 day colony assay by examining their clonal morphology. Transformed cells form colonies with a dense, criss-crossed or piled-up structure. A high percentage of the transformed colonies can be further propagated and will acquire additional neoplastic characteristics; i.e., anchorage independence, immortality, altered proteolytic activity, karyotype alterations, and finally, tumorigenicity.

  11. Influence of dose rate on the transformation of Syrian hamster embryo cells by fission-spectrum neutrons

    International Nuclear Information System (INIS)

    Jones, C.A.; Sedita, B.A.; Hill, C.K.; Elkind, M.M.

    1988-01-01

    Several explanations for this neutron dose-rate effect have been proposed, but further investigation is necessary to determine the mechanisms involved. In all cell transformation studies to date the immortalized, aneuploid 10T1/2 cell-line has been used. These cells may be premalignant; thus their response characteristics and, in particular, the nature of the transformation event, might differ from that in a normal, fibroblast cell. One reason for the present study was to determine whether the low-dose-rate effect of fission neutrons could be demonstrated in normal cells. If so, a normal cell system, which would more closely resemble a normal in vivo system, could be used for mechanistic studies. We chose Syrian hamster embryo (SHE) fibroblasts which are normal, diploid cells with a limited life span in culture. Upon exposure to low doses of ionizing radiation, the fraction of the cells that are transformed can be identified in a standard 8--10 day colony assay by examining their clonal morphology. Transformed cells form colonies with a dense, criss-crossed or piled-up structure. A high percentage of the transformed colonies can be further propagated and will acquire additional neoplastic characteristics; i.e., anchorage independence, immortality, altered proteolytic activity, karyotype alterations, and finally, tumorigenicity

  12. Suicide of EMT-6 tumor cells by decays from radioactively-labelled sensitizer adducts

    International Nuclear Information System (INIS)

    Roa, W.H.Y.; Chapman, J.D.

    1987-01-01

    Nitroaromatic radiosensitizers become metabolically bound preferentially to hypoxic cells and at least 10/sup 9/ adducts/cell can be tolerated as non-toxic. EMT-6 tumor cells have been incubated in hypoxia in the presence of /sup 3/H-Misonidazole and /sup 125/I-Azomycin Riboside for various times and the amount of /sup 3/H or /sup 125/I bound/cell was determined. Cells were stored as monolayers at 25 0 C for up to 96 hr to accumulate radioactive decays and transferred at various times to 37 0 C for colony-forming assays. No radiation inactivation was measured in cells which had incorporated at least 10/sup 6/ /sup 3/H or 10/sup 5/ /sup 125/I atoms. Previous studies had shown that -- 1% of MISO adducts to EMT-6 cells was associated with cellular DNA. These data indicate that the radiation-induced damage produced by these quantities of bound /sup 3/H or /sup 125/I causes little or not cell inactivation. The results of current studies to measure the colony-forming ability of sensitizer-labelled cells which have been stored in liquid nitrogen to facilitate the accumulation of more decays will be reported. These data suggest that a ''sensitizer-adduct suicide technique'' as a hypoxic cell selective adjunct to other cancer therapies is not feasible. These data are also instructive for those who attempt to develop radiolabelled ''tumor specific'' antibodies for therapeutic purposes

  13. Self-organization of human embryonic stem cells on micropatterns

    Science.gov (United States)

    Deglincerti, Alessia; Etoc, Fred; Guerra, M. Cecilia; Martyn, Iain; Metzger, Jakob; Ruzo, Albert; Simunovic, Mijo; Yoney, Anna; Brivanlou, Ali H.; Siggia, Eric; Warmflash, Aryeh

    2018-01-01

    Fate allocation in the gastrulating embryo is spatially organized as cells differentiate to specialized cell types depending on their positions with respect to the body axes. There is a need for in vitro protocols that allow the study of spatial organization associated with this developmental transition. While embryoid bodies and organoids can exhibit some spatial organization of differentiated cells, these methods do not yield consistent and fully reproducible results. Here, we describe a micropatterning approach where human embryonic stem cells are confined to disk-shaped, sub-millimeter colonies. After 42 hours of BMP4 stimulation, cells form self-organized differentiation patterns in concentric radial domains, which express specific markers associated with the embryonic germ layers, reminiscent of gastrulating embryos. Our protocol takes 3 days; it uses commercial microfabricated slides (CYTOO), human laminin-521 (LN-521) as extra-cellular matrix coating, and either conditioned or chemically-defined medium (mTeSR). Differentiation patterns within individual colonies can be determined by immunofluorescence and analyzed with cellular resolution. Both the size of the micropattern and the type of medium affect the patterning outcome. The protocol is appropriate for personnel with basic stem cell culture training. This protocol describes a robust platform for quantitative analysis of the mechanisms associated with pattern formation at the onset of gastrulation. PMID:27735934

  14. Image-based quantification and mathematical modeling of spatial heterogeneity in ESC colonies.

    Science.gov (United States)

    Herberg, Maria; Zerjatke, Thomas; de Back, Walter; Glauche, Ingmar; Roeder, Ingo

    2015-06-01

    Pluripotent embryonic stem cells (ESCs) have the potential to differentiate into cells of all three germ layers. This unique property has been extensively studied on the intracellular, transcriptional level. However, ESCs typically form clusters of cells with distinct size and shape, and establish spatial structures that are vital for the maintenance of pluripotency. Even though it is recognized that the cells' arrangement and local interactions play a role in fate decision processes, the relations between transcriptional and spatial patterns have not yet been studied. We present a systems biology approach which combines live-cell imaging, quantitative image analysis, and multiscale, mathematical modeling of ESC growth. In particular, we develop quantitative measures of the morphology and of the spatial clustering of ESCs with different expression levels and apply them to images of both in vitro and in silico cultures. Using the same measures, we are able to compare model scenarios with different assumptions on cell-cell adhesions and intercellular feedback mechanisms directly with experimental data. Applying our methodology to microscopy images of cultured ESCs, we demonstrate that the emerging colonies are highly variable regarding both morphological and spatial fluorescence patterns. Moreover, we can show that most ESC colonies contain only one cluster of cells with high self-renewing capacity. These cells are preferentially located in the interior of a colony structure. The integrated approach combining image analysis with mathematical modeling allows us to reveal potential transcription factor related cellular and intercellular mechanisms behind the emergence of observed patterns that cannot be derived from images directly. © 2015 International Society for Advancement of Cytometry.

  15. An in vitro expansion system for generation of human iPS cell-derived hepatic progenitor-like cells exhibiting a bipotent differentiation potential.

    Directory of Open Access Journals (Sweden)

    Ayaka Yanagida

    Full Text Available Hepatoblasts, hepatic stem/progenitor cells in liver development, have a high proliferative potential and the ability to differentiate into both hepatocytes and cholangiocytes. In regenerative medicine and drug screening for the treatment of severe liver diseases, human induced pluripotent stem (iPS cell-derived mature functional hepatocytes are considered to be a potentially good cell source. However, induction of proliferation of these cells is difficult ex vivo. To circumvent this problem, we generated hepatic progenitor-like cells from human iPS cells using serial cytokine treatments in vitro. Highly proliferative hepatic progenitor-like cells were purified by fluorescence-activated cell sorting using antibodies against CD13 and CD133 that are known cell surface markers of hepatic stem/progenitor cells in fetal and adult mouse livers. When the purified CD13(highCD133(+ cells were cultured at a low density with feeder cells in the presence of suitable growth factors and signaling inhibitors (ALK inhibitor A-83-01 and ROCK inhibitor Y-27632, individual cells gave rise to relatively large colonies. These colonies consisted of two types of cells expressing hepatocytic marker genes (hepatocyte nuclear factor 4α and α-fetoprotein and a cholangiocytic marker gene (cytokeratin 7, and continued to proliferate over long periods of time. In a spheroid formation assay, these cells were found to express genes required for mature liver function, such as cytochrome P450 enzymes, and secrete albumin. When these cells were cultured in a suitable extracellular matrix gel, they eventually formed a cholangiocytic cyst-like structure with epithelial polarity, suggesting that human iPS cell-derived hepatic progenitor-like cells have a bipotent differentiation ability. Collectively these data indicate that this novel procedure using an in vitro expansion system is useful for not only liver regeneration but also for the determination of molecular mechanisms that

  16. Radiosensitivity of human haematopoietic stem/progenitor cells

    International Nuclear Information System (INIS)

    Kato, Kengo; Kashiwakura, Ikuo; Omori, Atsuko

    2013-01-01

    The haematopoietic system is regenerative tissue with a high proliferative potential; therefore, haematopoietic stem cells (HSCs) are sensitive to extracellular oxidative stress caused by radiation and chemotherapeutic agents. An understanding of this issue can help predict haematopoietic recovery from radiation exposure as well as the extent of radiation damage to the haematopoietic system. In the present study, the radiosensitivity of human lineage-committed myeloid haematopoietic stem/progenitor cells (HSPCs), including colony-forming unit–granulocyte macrophage, burst-forming unit–erythroid and colony-forming unit–granulocyte–erythroid–macrophage–megakaryocyte cells, which are contained in adult individual peripheral blood (PB) and fetus/neonate placental/umbilical cord blood (CB), were studied. The PB of 59 healthy individual blood donors and the CB of 42 neonates were investigated in the present study. HSPCs prepared from PB and CB were exposed to 0.5 or 2 Gy x-irradiation. The results showed that large individual differences exist in the surviving fraction of cells. In the case of adult PB, a statistically significant negative correlation was observed between the surviving fraction observed at a dose of 0.5 Gy and the age of the blood donors; however, none of these correlations were observed after 2 Gy x-irradiation. In addition, seasonal and gender variation were observed in the surviving fraction of CB HSPCs. The present results suggest that there are large individual differences in the surviving fraction of HSPCs contained in both adult PB and fetus/neonate CB. In addition, some factors, including the gender, age and season of birth, affect the radiosensitivity of HSPCs, especially with a relatively low-dose exposure. (paper)

  17. Distinctive transforming genes in x-ray-transformed mammalian cells

    International Nuclear Information System (INIS)

    Borek, C.; Ong, A.; Mason, H.

    1987-01-01

    DNAs from hamster embryo cells and mouse C3H/10T1/2 cells transformed in vitro by x-irradiation into malignant cells transmit the radiation transformation phenotype by producing transformed colonies (transfectants) in two mouse recipient lines, the NIH 3T3 and C3H/101/2 cells, and in a rat cell line, the Rat-2 cells. DNAs from unirradiated cells or irradiated and visibly untransformed cells do not produce transformed colonies. The transfectant grow in agar and form tumors in nude mice. Treatment of the DNAs with restriction endonucleases prior to transfection indicates that the same transforming gene (oncogene) is present in each of the transformed mouse cells and is the same in each of the transformed hamster cells. Southern blot analysis of 3T3 or Rat-2 transfectants carrying oncogenes from radiation-transformed C3H/10T1/2 or hamster cells indicates that the oncogenes responsible for the transformation of 3T3 cells are not the Ki-ras, Ha-ras, N-ras genes, nor are they neu, trk, raf, abl, or fms. The work demonstrates that DNAs from mammalian cells transformed into malignancy by direct exposure in vitro to radiation contain genetic sequences with detectable transforming activity in three recipient cell lines. The results provide evidence that DNA is the target of radiation carcinogenesis induced at a cellular level in vitro. The experiments indicate that malignant radiogenic transformation in vitro of hamster embryo and mouse C3H/10T1/2 cells involves the activation of unique non-ras transforming genes, which heretofore have not been described

  18. Mesenchymal stem cells from cortical bone demonstrate increased clonal incidence, potency, and developmental capacity compared to their bone marrow–derived counterparts

    Directory of Open Access Journals (Sweden)

    Daniel Blashki

    2016-08-01

    Full Text Available In this study, we show that matrix dense cortical bone is the more potent compartment of bone than bone marrow as a stromal source for mesenchymal stem cells as isolated from adult rats. Lineage-depleted cortical bone-mesenchymal stem cells demonstrated >150-fold enrichment of colony forming unit–fibroblasts per cell incidence. compared to lineage-depleted bone marrow-mesenchymal stem cells, corresponding to a 70-fold increase in absolute recovered colony forming unit–fibroblasts. The composite phenotype Lin−/CD45−/CD31−/VLA-1+/Thy-1+ enriched for clonogenic mesenchymal stem cells solely from cortical bone–derived cells from which 70% of clones spontaneously differentiated into all lineages of bone, cartilage, and adipose. Both populations generated vascularized bone tissue within subcutaneous implanted collagen scaffolds; however, cortical bone–derived cells formed significantly more osteoid than bone marrow counterparts, quantified by histology. The data demonstrate that our isolation protocol identifies and validates mesenchymal stem cells with superior clonal, proliferative, and developmental potential from cortical bone compared to the bone marrow niche although marrow persists as the typical source for mesenchymal stem cells both in the literature and current pre-clinical therapies.

  19. Studies on the effects of ionizing radiation and chemotherapeutic agents on hematopoiesis according to the stem-cell kinetics

    International Nuclear Information System (INIS)

    Hirashima, Kunitake

    1975-01-01

    The fundamental problem of the effects of ionizing radiation and antineoplastic drugs on hematopoiesis can be explained by the kinetic study on the hematopoietic stem-cell population. Quantitative comparison of a single x-irradiation and a single administration of several antineoplastic drugs on the stem-cell population was performed by the splenic colony-forming method. The repopulation pattern of stem-cells in mice after a single 150 rad irradiation was compared with that after the administration of corresponding dose of cyclophosphamide. It was demonstrated that the additional administration of cyclophosphamide immediately after the x-irradiation significantly accelerated repopulation of the stem-cell compartment. The mechanism of repopulation of the stem-cell compartment after partial irradiation was also studied according to the immigration theory of stem-cells. An in vitro colony-forming technique for the human bone marrow cells was introduced and compared with other assay methods for stem-cells. From the hematological observations of accidentally irradiated patients, it was determined that the thromboelastogram values were regarded as one of the most useful indicators for detecting the earliest recovery sign of the hematopoietic stem-cells. (Evans, J.)

  20. Fanconi Anemia Mesenchymal Stromal Cells-Derived Glycerophospholipids Skew Hematopoietic Stem Cell Differentiation Through Toll-Like Receptor Signaling.

    Science.gov (United States)

    Amarachintha, Surya; Sertorio, Mathieu; Wilson, Andrew; Li, Xiaoli; Pang, Qishen

    2015-11-01

    Fanconi anemia (FA) patients develop bone marrow (BM) failure or leukemia. One standard care for these devastating complications is hematopoietic stem cell transplantation. We identified a group of mesenchymal stromal cells (MSCs)-derived metabolites, glycerophospholipids, and their endogenous inhibitor, 5-(tetradecyloxy)-2-furoic acid (TOFA), as regulators of donor hematopoietic stem and progenitor cells. We provided two pieces of evidence that TOFA could improve hematopoiesis-supporting function of FA MSCs: (a) limiting-dilution cobblestone area-forming cell assay revealed that TOFA significantly increased cobblestone colonies in Fanca-/- or Fancd2-/- cocultures compared to untreated cocultures. (b) Competitive repopulating assay using output cells collected from cocultures showed that TOFA greatly alleviated the abnormal expansion of the donor myeloid (CD45.2+Gr1+Mac1+) compartment in both peripheral blood and BM of recipient mice transplanted with cells from Fanca-/- or Fancd2-/- cocultures. Furthermore, mechanistic studies identified Tlr4 signaling as the responsible pathway mediating the effect of glycerophospholipids. Thus, targeting glycerophospholipid biosynthesis in FA MSCs could be a therapeutic strategy to improve hematopoiesis and stem cell transplantation. © 2015 AlphaMed Press.

  1. Aldehyde dehydrogenase activity selects for the holoclone phenotype in prostate cancer cells

    International Nuclear Information System (INIS)

    Doherty, R.E.; Haywood-Small, S.L.; Sisley, K.; Cross, N.A.

    2011-01-01

    Highlights: ► Isolated ALDH Hi PC3 cells preferentially form primitive holoclone-type colonies. ► Primitive holoclone colonies are predominantly ALDH Lo but contain rare ALDH Hi cells. ► Holoclone-forming cells are not restricted to the ALDH Hi population. ► ALDH phenotypic plasticity occurs in PC3 cells (ALDH Lo to ALDH Hi and vice versa). ► ALDH Hi cells are observed but very rare in PC3 spheroids grown in stem cell medium. -- Abstract: Aldehyde dehydrogenase 1 (ALDH) activity is considered to be a marker of cancer stem cells (CSCs) in many tumour models, since these cells are more proliferative and tumourigenic than ALDH Lo cells in experimental models. However it is unclear whether all CSC-like cells are within the ALDH Hi population, or whether all ALDH Hi cells are highly proliferative and tumourigenic. The ability to establish a stem cell hierarchy in vitro, whereby sub-populations of cells have differing proliferative and differentiation capacities, is an alternate indication of the presence of stem cell-like populations within cell lines. In this study, we have examined the interaction between ALDH status and the ability to establish a stem cell hierarchy in PC3 prostate cancer cells. We demonstrate that PC3 cells contain a stem cell hierarchy, and isolation of ALDH Hi cells enriches for the most primitive holoclone population, however holoclone formation is not restricted to ALDH Hi cells. In addition, we show that ALDH activity undergoes phenotypic plasticity, since the ALDH Lo population can develop ALDH Hi populations comparable to parental cells within 2 weeks in culture. Furthermore, we show that the majority of ALDH Hi cells are found within the least primitive paraclone population, which is circumvented by culturing PC3 cells as spheroids in defined medium favouring stem cell characteristics. Although ALDH Hi status enriches for holoclone formation, this activity may be mediated by a minority of ALDH Hi cells.

  2. Staurosporine induces different cell death forms in cultured rat astrocytes

    International Nuclear Information System (INIS)

    Simenc, Janez; Lipnik-Stangelj, Metoda

    2012-01-01

    Astroglial cells are frequently involved in malignant transformation. Besides apoptosis, necroptosis, a different form of regulated cell death, seems to be related with glioblastoma genesis, proliferation, angiogenesis and invasion. In the present work we elucidated mechanisms of necroptosis in cultured astrocytes, and compared them with apoptosis, caused by staurosporine. Cultured rat cortical astrocytes were used for a cell death studies. Cell death was induced by different concentrations of staurosporine, and modified by inhibitors of apoptosis (z-vad-fmk) and necroptosis (nec-1). Different forms of a cell death were detected using flow cytometry. We showed that staurosporine, depending on concentration, induces both, apoptosis as well as necroptosis. Treatment with 10 −7 M staurosporine increased apoptosis of astrocytes after the regeneration in a staurosporine free medium. When caspases were inhibited, apoptosis was attenuated, while necroptosis was slightly increased. Treatment with 10 −6 M staurosporine induced necroptosis that occurred after the regeneration of astrocytes in a staurosporine free medium, as well as without regeneration period. Necroptosis was significantly attenuated by nec-1 which inhibits RIP1 kinase. On the other hand, the inhibition of caspases had no effect on necroptosis. Furthermore, staurosporine activated RIP1 kinase increased the production of reactive oxygen species, while an antioxidant BHA significantly attenuated necroptosis. Staurosporine can induce apoptosis and/or necroptosis in cultured astrocytes via different signalling pathways. Distinction between different forms of cell death is crucial in the studies of therapy-induced necroptosis

  3. Altered hematopoiesis in trisomy 21 as revealed through in vitro differentiation of isogenic human pluripotent cells

    Science.gov (United States)

    MacLean, Glenn A.; Menne, Tobias F.; Guo, Guoji; Sanchez, Danielle J.; Park, In-Hyun; Daley, George Q.; Orkin, Stuart H.

    2012-01-01

    Trisomy 21 is associated with hematopoietic abnormalities in the fetal liver, a preleukemic condition termed transient myeloproliferative disorder, and increased incidence of acute megakaryoblastic leukemia. Human trisomy 21 pluripotent cells of various origins, human embryionic stem (hES), and induced pluripotent stem (iPS) cells, were differentiated in vitro as a model to recapitulate the effects of trisomy on hematopoiesis. To mitigate clonal variation, we isolated disomic and trisomic subclones from the same parental iPS line, thereby generating subclones isogenic except for chromosome 21. Under differentiation conditions favoring development of fetal liver-like, γ-globin expressing, definitive hematopoiesis, we found that trisomic cells of hES, iPS, or isogenic origins exhibited a two- to fivefold increase in a population of CD43+(Leukosialin)/CD235+(Glycophorin A) hematopoietic cells, accompanied by increased multilineage colony-forming potential in colony-forming assays. These findings establish an intrinsic disturbance of multilineage myeloid hematopoiesis in trisomy 21 at the fetal liver stage. PMID:23045682

  4. Fractalkine expression induces endothelial progenitor cell lysis by natural killer cells.

    Directory of Open Access Journals (Sweden)

    Dilyana Todorova

    Full Text Available BACKGROUND: Circulating CD34(+ cells, a population that includes endothelial progenitors, participate in the maintenance of endothelial integrity. Better understanding of the mechanisms that regulate their survival is crucial to improve their regenerative activity in cardiovascular and renal diseases. Chemokine-receptor cross talk is critical in regulating cell homeostasis. We hypothesized that cell surface expression of the chemokine fractalkine (FKN could target progenitor cell injury by Natural Killer (NK cells, thereby limiting their availability for vascular repair. METHODOLOGY/PRINCIPAL FINDINGS: We show that CD34(+-derived Endothelial Colony Forming Cells (ECFC can express FKN in response to TNF-α and IFN-γ inflammatory cytokines and that FKN expression by ECFC stimulates NK cell adhesion, NK cell-mediated ECFC lysis and microparticles release in vitro. The specific involvement of membrane FKN in these processes was demonstrated using FKN-transfected ECFC and anti-FKN blocking antibody. FKN expression was also evidenced on circulating CD34(+ progenitor cells and was detected at higher frequency in kidney transplant recipients, when compared to healthy controls. The proportion of CD34(+ cells expressing FKN was identified as an independent variable inversely correlated to CD34(+ progenitor cell count. We further showed that treatment of CD34(+ circulating cells isolated from adult blood donors with transplant serum or TNF-α/IFN-γ can induce FKN expression. CONCLUSIONS: Our data highlights a novel mechanism by which FKN expression on CD34(+ progenitor cells may target their NK cell mediated killing and participate to their immune depletion in transplant recipients. Considering the numerous diseased contexts shown to promote FKN expression, our data identify FKN as a hallmark of altered progenitor cell homeostasis with potential implications in better evaluation of vascular repair in patients.

  5. The Absence of a Mature Cell Wall Sacculus in Stable Listeria monocytogenes L-Form Cells Is Independent of Peptidoglycan Synthesis.

    Science.gov (United States)

    Studer, Patrick; Borisova, Marina; Schneider, Alexander; Ayala, Juan A; Mayer, Christoph; Schuppler, Markus; Loessner, Martin J; Briers, Yves

    2016-01-01

    L-forms are cell wall-deficient variants of otherwise walled bacteria that maintain the ability to survive and proliferate in absence of the surrounding peptidoglycan sacculus. While transient or unstable L-forms can revert to the walled state and may still rely on residual peptidoglycan synthesis for multiplication, stable L-forms cannot revert to the walled form and are believed to propagate in the complete absence of peptidoglycan. L-forms are increasingly studied as a fundamental biological model system for cell wall synthesis. Here, we show that a stable L-form of the intracellular pathogen Listeria monocytogenes features a surprisingly intact peptidoglycan synthesis pathway including glycosyl transfer, in spite of the accumulation of multiple mutations during prolonged passage in the cell wall-deficient state. Microscopic and biochemical analysis revealed the presence of peptidoglycan precursors and functional glycosyl transferases, resulting in the formation of peptidoglycan polymers but without the synthesis of a mature cell wall sacculus. In conclusion, we found that stable, non-reverting L-forms, which do not require active PG synthesis for proliferation, may still continue to produce aberrant peptidoglycan.

  6. STAT3 signaling pathway is necessary for cell survival and tumorsphere forming capacity in ALDH{sup +}/CD133{sup +} stem cell-like human colon cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Li, E-mail: lin.796@osu.edu [Center for Childhood Cancer, The Research Institute at Nationwide Children' s Hospital, Department of Pediatrics, Internal Medicine, College of Medicine, The Ohio State University, Columbus, OH 43205 (United States); Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030 (China); Fuchs, James; Li, Chenglong [Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, OH 43210 (United States); Olson, Veronica [Center for Childhood Cancer, The Research Institute at Nationwide Children' s Hospital, Department of Pediatrics, Internal Medicine, College of Medicine, The Ohio State University, Columbus, OH 43205 (United States); Bekaii-Saab, Tanios [Internal Medicine, College of Medicine, The Ohio State University, Columbus, OH 43210 (United States); Lin, Jiayuh, E-mail: lin.674@osu.edu [Center for Childhood Cancer, The Research Institute at Nationwide Children' s Hospital, Department of Pediatrics, Internal Medicine, College of Medicine, The Ohio State University, Columbus, OH 43205 (United States)

    2011-12-16

    Highlights: Black-Right-Pointing-Pointer The phosphorylated or activated form of STAT3 was expressed in colon cancer stem-like cells. Black-Right-Pointing-Pointer STAT3 inhibitor, FLLL32 inhibits P-STAT3 and STAT3 target genes in colon cancer stem-like cells. Black-Right-Pointing-Pointer Inhibition of STAT3 resulted in decreased cell viability and reduced numbers of tumorspheres. Black-Right-Pointing-Pointer STAT3 is required for survival and tumorsphere forming capacity in colon cancer stem-like cells. Black-Right-Pointing-Pointer Targeting STAT3 in cancer stem-like cells may offer a novel treatment approach for colon cancer. -- Abstract: Persistent activation of Signal Transducers and Activators of Transcription 3 (STAT3) is frequently detected in colon cancer. Increasing evidence suggests the existence of a small population of colon cancer stem or cancer-initiating cells may be responsible for tumor initiation, metastasis, and resistance to chemotherapy and radiation. Whether STAT3 plays a role in colon cancer-initiating cells and the effect of STAT3 inhibition is still unknown. Flow cytometry was used to isolate colon cancer stem-like cells from three independent human colon cancer cell lines characterized by both aldehyde dehydrogenase (ALDH)-positive and CD133-positive subpopulation (ALDH{sup +}/CD133{sup +}). The effects of STAT3 inhibition in colon cancer stem-like cells were examined. The phosphorylated or activated form of STAT3 was expressed in colon cancer stem-like cells and was reduced by a STAT3-selective small molecular inhibitor, FLLL32. FLLL32 also inhibited the expression of potential STAT3 downstream target genes in colon cancer stem-like cells including survivin, Bcl-XL, as well as Notch-1, -3, and -4, which may be involved in stem cell function. Furthermore, FLLL32 inhibited cell viability and tumorsphere formation as well as induced cleaved caspase-3 in colon cancer stem-like cells. FLLL32 is more potent than curcumin as evidenced with lower

  7. A method for culturing human hair follicle cells.

    Science.gov (United States)

    Weterings, P J; Vermorken, A J; Bloemendal, H

    1981-01-01

    For the first time a method for culturing human hair follicle cells is described. The bovine eye lens capsule, a basement membrane-like structure, is used as the substrate for the cultures. In a culture medium supplemented with hydrocortisone and insulin about 70% of the original follicles will form growing colonies of diploid keratinocytes.

  8. Isolation and characterization of NIH 3T3 cells expressing polyomavirus small T antigen

    International Nuclear Information System (INIS)

    Noda, T.; Satake, M.; Robins, T.; Ito, Y.

    1986-01-01

    The polyomavirus small T-antigen gene, together with the polyomavirus promoter, was inserted into retrovirus vector pGV16 which contains the Moloney sarcoma virus long terminal repeat and neomycin resistance gene driven by the simian virus 40 promoter. This expression vector, pGVST, was packaged into retrovirus particles by transfection of PSI2 cells which harbor packaging-defective murine retrovirus genome. NIH 3T3 cells were infected by this replication-defective retrovirus containing pGVST. Of the 15 G418-resistant cell clones, 8 express small T antigen at various levels as revealed by immunoprecipitation. A cellular protein with an apparent molecular weight of about 32,000 coprecipitates with small T antigen. Immunofluorescent staining shows that small T antigen is mainly present in the nuclei. Morphologically, cells expressing small T antigen are indistinguishable from parental NIH 3T3 cells and have a microfilament pattern similar to that in parental NIH 3T3 cells. Cells expressing small T antigen form a flat monolayer but continue to grow beyond the saturation density observed for parental NIH 3T3 cells and eventually come off the culture plate as a result of overconfluency. There is some correlation between the level of expression of small T antigen and the growth rate of the cells. Small T-antigen-expressing cells form small colonies in soft agar. However, the proportion of cells which form these small colonies is rather small. A clone of these cells tested did not form tumors in nude mice within 3 months after inoculation of 10 6 cells per animal. Thus, present studies establish that the small T antigen of polyomavirus is a second nucleus-localized transforming gene product of the virus (the first one being large T antigen) and by itself has a function which is to stimulate the growth of NIH 3T3 cells beyond their saturation density in monolayer culture

  9. Elucidating mechanical transition effects of invading cancer cells with a subnucleus-scaled microfluidic serial dimensional modulation device†

    OpenAIRE

    Mak, Michael; Reinhart-King, Cynthia A.; Erickson, David

    2013-01-01

    Mechanical boundaries that define and regulate biological processes, such as cell-cell junctions and dense extracellular matrix networks, exist throughout the physiological landscape. During metastasis, cancer cells are able to invade across these barriers and spread to distant tissues. While transgressing boundaries is a necessary step for distal colonies to form, little is known about interface effects on cell behavior during invasion. Here we introduce a device and metric to assess cell tr...

  10. Stem cell collection in unmanipulated HLA-haploidentical/mismatched related transplantation with combined granulocyte-colony stimulating factor-mobilised blood and bone marrow for patients with haematologic malignancies: the impact of donor characteristics and procedural settings.

    Science.gov (United States)

    Zhang, C; Chen, X-H; Zhang, X; Gao, L; Gao, L; Kong, P-Y; Peng, X-G; Sun, A-H; Gong, Y; Zeng, D-F; Wang, Q-Y

    2010-06-01

    Unmanipulated haploidentical/mismatched related transplantation with combined granulocyte-colony stimulating factor-mobilised peripheral blood stem cells (G-PBSCs) and granulocyte-colony stimulating factor-mobilised bone marrow (G-BM) has been developed as an alternative transplantation strategy for patients with haematologic malignancies. However, little information is available about the factors predicting the outcome of peripheral blood stem cell (PBSC) collection and bone marrow (BM) harvest in this transplantation. The effects of donor characteristics and procedure factors on CD34(+) cell yield were investigated. A total of 104 related healthy donors received granulocyte-colony stimulating factor (G-CSF) followed by PBSC collection and BM harvest. Male donors had significantly higher yields compared with female donors. In multiple regression analysis for peripheral blood collection, age and flow rate were negatively correlated with cell yield, whereas body mass index, pre-aphaeresis white blood cell (WBC) and circulating immature cell (CIC) counts were positively correlated with cell yields. For BM harvest, age was negatively correlated with cell yields, whereas pre-BM collection CIC counts were positively correlated with cell yield. All donors achieved the final product of >or=6 x10(6) kg(-1) recipient body weight. This transplantation strategy has been shown to be a feasible approach with acceptable outcomes in stem cell collection for patients who received HLA-haploidentical/mismatched transplantation with combined G-PBSCs and G-BM. In donors with multiple high-risk characteristics for poor aphaeresis CD34(+) cell yield, BM was an alternative source.

  11. Bystander effects on mammalian cells induced by carbon ions

    International Nuclear Information System (INIS)

    Wang Jufang; Zhao Jing; Ma Qiufeng; Chinese Academy of Sciences, Beijing; Li Weijian; Zhou Guangming; Dang Bingrong; Mao Limin; Feng Yan

    2004-01-01

    Bystander effects on unirradiated V79 cells were observed by irradiated conditioned medium (ICM) method and co-cultured with carbon-ion-irradiated V79 cells. The results showed that the colony formation efficiency of unirradiated cells is obviously decreased by ICM. After co-culture with carbon-ion-irradiated cells for some time, the colony formation efficiency of co-cultured cells was lower than expected results assuming no bystander effects. The micronucleus frequency and hprt gene mutation rate was almost the same as expected results. Cytotoxic factor(s), which was effective for cell growth but not for micronucleus and mutation on unirradiated cells, might be released by irradiated cells. (authors)

  12. Establishment of Cancer Stem Cell Cultures from Human Conventional Osteosarcoma.

    Science.gov (United States)

    Palmini, Gaia; Zonefrati, Roberto; Mavilia, Carmelo; Aldinucci, Alessandra; Luzi, Ettore; Marini, Francesca; Franchi, Alessandro; Capanna, Rodolfo; Tanini, Annalisa; Brandi, Maria Luisa

    2016-10-14

    The current improvements in therapy against osteosarcoma (OS) have prolonged the lives of cancer patients, but the survival rate of five years remains poor when metastasis has occurred. The Cancer Stem Cell (CSC) theory holds that there is a subset of tumor cells within the tumor that have stem-like characteristics, including the capacity to maintain the tumor and to resist multidrug chemotherapy. Therefore, a better understanding of OS biology and pathogenesis is needed in order to advance the development of targeted therapies to eradicate this particular subset and to reduce morbidity and mortality among patients. Isolating CSCs, establishing cell cultures of CSCs, and studying their biology are important steps to improving our understanding of OS biology and pathogenesis. The establishment of human-derived OS-CSCs from biopsies of OS has been made possible using several methods, including the capacity to create 3-dimensional stem cell cultures under nonadherent conditions. Under these conditions, CSCs are able to create spherical floating colonies formed by daughter stem cells; these colonies are termed "cellular spheres". Here, we describe a method to establish CSC cultures from primary cell cultures of conventional OS obtained from OS biopsies. We clearly describe the several passages required to isolate and characterize CSCs.

  13. Micronucleus induction and reproductive death in a human cell line exposed to low-energy argon beam

    International Nuclear Information System (INIS)

    Courdi, A.; Mari, D.; Herault, J.; Chauvel, P.

    1995-01-01

    The aim of this study was to measure the biological efficiency of a low-energy argon beam (E=7.1 MeV/nucleon, LET=1590 keV/μm) on a human melanoma cell line (CAL4) established in our Institute. Two different methods were used: the micronucleus (MN) test and the colony-forming assay. MN are scored in binucleate cells (BNC) and are formed from acentric fragments or whole chromosomes that have not been incorporated into daughter nuclei at mitosis. The colony-forming assay quantifies reproductive death. Parallel experiments were run with cobalt gamma-rays for comparison. After Co irradiation, the MN-free BNC dose-response curve coincided with that of the loss of colony-forming ability, suggesting the potential of the former as a predictive test of cell killing. After Ar irradiation, there was a dissociation between the two effects, especially at high doses: cell death was greater than the frequency of BNC with MN. The inactivation cross-section was 74 μm 2 ; it was 39 μm 2 for MN yield. Therefore, the relative biological effectiveness (RBE) was higher for cell killing than for MN yield (0.8 and 0.5, respectively, at a Co dose of 3 Gy). The total MN count in BNC followed the same pattern of response as the fraction of BNC with MN. However, multiple (>2) MN in BNC were more frequently observed after low-dose Ar irradiation than after gamma-ray exposure (RBE > 1). Moreover, the frequency of multiple MN induction exceeded that expected from a Poisson distribution at all dose levels of Ar irradiation. (orig.)

  14. Basal CD34+ Cell Count Predicts Peripheral Blood Stem Cell Mobilization in Healthy Donors after Administration of Granulocyte Colony-Stimulating Factor: A Longitudinal, Prospective, Observational, Single-Center, Cohort Study.

    Science.gov (United States)

    Martino, Massimo; Gori, Mercedes; Pitino, Annalisa; Gentile, Massimo; Dattola, Antonia; Pontari, Antonella; Vigna, Ernesto; Moscato, Tiziana; Recchia, Anna Grazia; Barilla', Santina; Tripepi, Giovanni; Morabito, Fortunato

    2017-07-01

    A longitudinal, prospective, observational, single-center, cohort study on healthy donors (HDs) was designed to identify predictors of CD34 + cells on day 5 with emphasis on the predictive value of the basal CD34 + cell count. As potential predictors of mobilization, age, sex, body weight, height, blood volume as well as white blood cell count, peripheral blood (PB) mononuclear cells, platelet count, hematocrit, and hemoglobin levels were considered. Two different evaluations of CD34 + cell counts were determined for each donor: baseline (before granulocyte colony-stimulating factor [G-CSF] administration) and in PB after G-CSF administration on the morning of the fifth day (day 5). A total of 128 consecutive HDs (66 males) with a median age of 43 years were enrolled. CD34 + levels on day 5 displayed a non-normal distribution, with a median value of 75.5 cells/µL. To account for the non-normal distribution of the dependent variable, a quantile regression analysis to predict CD34 + on day 5 using the baseline value of CD34 + as the key predictor was performed. On crude analysis, a baseline value of CD34 + ranging from .5 cells/µL to 1 cells/µL predicts a median value of 50 cells/µL on day 5; a value of 2 cells/µL predicts a median value of 70.7 cells/µL; a value of 3 cells/µL to 4 cells/µL predicts a median value of 91.3 cells/µL, and a value ≥ 5 predicts a median value of 112 cells/µL. In conclusion, the baseline PB CD34 + cell count correlates with the effectiveness of allogeneic PB stem cell mobilization and could be useful to plan the collection. Copyright © 2017 The American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

  15. Cutaneous double-hit B-cell lymphoma: an aggressive form of B-cell lymphoma with a propensity for cutaneous dissemination.

    Science.gov (United States)

    Magro, Cynthia M; Wang, Xuan; Subramaniyam, Shivakumar; Darras, Natasha; Mathew, Susan

    2014-04-01

    Diffuse large cell B-cell lymphoma of the skin is most commonly represented by diffuse large cell variants of primary cutaneous follicle center cell lymphoma and the leg-type lymphoma. In a minority of cases, the infiltrates are an expression of stage 4 disease of established extracutaneous B-cell lymphoma. We describe 3 patients with an aggressive form of B-cell lymphoma secondarily involving the skin. Two of the patients were in the ninth decade of life, whereas 1 patient was 34 years of age. In the elderly patients, there was an antecedent and/or concurrent history of follicular lymphoma, whereas in the younger patient, the tumor was a de novo presentation of this aggressive form of lymphoma. The elderly patients succumbed to their disease within less than a year from the time of diagnosis, whereas 1 patient is alive but with persistent and progressive disease despite chemotherapeutic intervention. The infiltrates in all 3 cases were diffuse and composed of large malignant hematopoietic cells that exhibited a round nucleus with a finely dispersed chromatin. Phenotypically, the tumor cells were Bcl-2 and CD10 positive, whereas Bcl-6 and Mum-1 showed variable positivity. One case showed combined Mum-1 positivity along with an acute lymphoblastic lymphoma phenotype, including the absence of CD20 expression. In each case, there was a c-MYC and BCL2/IGH rearrangement diagnostic of double-hit lymphoma. In one case, there was an additional BCL6 rearrangement, defining what is in essence triple-hit lymphoma. In conclusion, double-hit lymphoma is an aggressive form of B-cell neoplasia resistant to standard chemotherapy regimens, which in many but not all cases represents tumor progression in the setting of a lower grade B-cell malignancy.

  16. Effects of high glucose on mesenchymal stem cell proliferation and differentiation

    DEFF Research Database (Denmark)

    Li, Yu-Ming; Schilling, Tatjana; Benisch, Peggy

    2007-01-01

    High glucose (HG) concentrations impair cellular functions and induce apoptosis. Exposition of mesenchymal stem cells (MSC) to HG was reported to reduce colony forming activity and induce premature senescence. We characterized the effects of HG on human MSC in vitro using telomerase-immortalized...

  17. Angiocrine factors from Akt-activated endothelial cells balance self-renewal and differentiation of haematopoietic stem cells

    Science.gov (United States)

    Kobayashi, Hideki; Butler, Jason M.; O'Donnell, Rebekah; Kobayashi, Mariko; Ding, Bi-Sen; Bonner, Bryant; Chiu, Vi K.; Nolan, Daniel J.; Shido, Koji; Benjamin, Laura; Rafii, Shahin

    2010-01-01

    Endothelial cells establish an instructive vascular niche that reconstitutes haematopoietic stem and progenitor cells (HSPCs) through release of specific paracrine growth factors, known as angiocrine factors. However, the mechanism by which endothelial cells balance the rate of proliferation and lineage-specific differentiation of HSPCs is unknown. Here, we demonstrate that Akt activation in endothelial cells, through recruitment of mTOR, but not the FoxO pathway, upregulates specific angiocrine factors that support expansion of CD34−Flt3− KLS HSPCs with long-term haematopoietic stem cell (LT-HSC) repopulation capacity. Conversely, co-activation of Akt-stimulated endothelial cells with p42/44 MAPK shifts the balance towards maintenance and differentiation of the HSPCs. Selective activation of Akt1 in the endothelial cells of adult mice increased the number of colony forming units in the spleen and CD34−Flt3− KLS HSPCs with LT-HSC activity in the bone marrow, accelerating haematopoietic recovery. Therefore, the activation state of endothelial cells modulates reconstitution of HSPCs through the upregulation of angiocrine factors, with Akt–mTOR-activated endothelial cells supporting the self-renewal of LT-HSCs and expansion of HSPCs, whereas MAPK co-activation favours maintenance and lineage-specific differentiation of HSPCs. PMID:20972423

  18. Characterization of differential properties of rabbit tendon stem cells and tenocytes

    Directory of Open Access Journals (Sweden)

    Wang James

    2010-01-01

    Full Text Available Abstract Background Tendons are traditionally thought to consist of tenocytes only, the resident cells of tendons; however, a recent study has demonstrated that human and mouse tendons also contain stem cells, referred to as tendon stem/progenitor cells (TSCs. However, the differential properties of TSCs and tenocytes remain largely undefined. This study aims to characterize the properties of these tendon cells derived from rabbits. Methods TSCs and tenocytes were isolated from patellar and Achilles tendons of rabbits. The differentiation potential and cell marker expression of the two types of cells were examined using histochemical, immunohistochemical, and qRT-PCR analysis as well as in vivo implantation. In addition, morphology, colony formation, and proliferation of TSCs and tenocytes were also compared. Results It was found that TSCs were able to differentiate into adipocytes, chondrocytes, and osteocytes in vitro, and form tendon-like, cartilage-like, and bone-like tissues in vivo. In contrast, tenocytes had little such differentiation potential. Moreover, TSCs expressed the stem cell markers Oct-4, SSEA-4, and nucleostemin, whereas tenocytes expressed none of these markers. Morphologically, TSCs possessed smaller cell bodies and larger nuclei than ordinary tenocytes and had cobblestone-like morphology in confluent culture whereas tenocytes were highly elongated. TSCs also proliferated more quickly than tenocytes in culture. Additionally, TSCs from patellar tendons formed more numerous and larger colonies and proliferated more rapidly than TSCs from Achilles tendons. Conclusions TSCs exhibit distinct properties compared to tenocytes, including differences in cell marker expression, proliferative and differentiation potential, and cell morphology in culture. Future research should investigate the mechanobiology of TSCs and explore the possibility of using TSCs to more effectively repair or regenerate injured tendons.

  19. Radiosensitization of C225 on human non-small cell lung cancer cell line H-520

    International Nuclear Information System (INIS)

    Zhang Yingdong; Wang Junjie; Liu Feng; Zhao Yong

    2008-01-01

    Objective: To investigate the efficacy of C225 (cetuximab), a chimeric human-mouse anti-epithelial growth factor receptor monoclonal antibody, combined with 60 Co gamma irradiation against human non-small cell lung cancer cell line H-520. Methods: H-520 cells were treated either with different dose of 60 Co irradiation (1,2,4,6,8 and 10 Gy)alone or together with C225 (100 nmol/L). Colony forming capacity was determined to create the survival curve 10 days after the treatment. Cells in different groups were harvested 72 hours after irradiation for apoptosis analysis or 48 hours after irradiation for cell cycle analysis by flow cytometry assay. Results: The clone number in combinational treatment group was less than that in irradiation only group, which suggested that the cell survival rate in the combinational treatment group was significantly decreased comparing with irradiation only group (F=6.36, P O + G 1 phases for C225 treatment, in G 2 + M phases for 60 Co irradiation, and in both G 0 + G 1 and G 2 + M phases for C225 in combination with 60 Co irradiation. Conclusions: C225 has radiosensitizing effects on H-520 cells, which may through the enhancement of 60 Co irradiation-induced cell death and cell cycle arrest. This study provides a supportive evidence for clinical treatment in non-small cell lung cancer. (authors)

  20. Colony formation by sublethally heat-injured Zygosaccharomyces rouxii as affected by solutes in the recovery medium and procedure for sterilizing medium.

    Science.gov (United States)

    Golden, D A; Beuchat, L R

    1990-01-01

    Recovery and colony formation by healthy and sublethally heat-injured cells of Zygosaccharomyces rouxii as influenced by the procedure for sterilizing recovery media (YM agar [YMA], wort agar, cornmeal agar, and oatmeal agar) were investigated. Media were supplemented with various concentrations of glucose, sucrose, glycerol, or sorbitol and sterilized by autoclaving (110 degrees C, 15 min) and by repeated treatment with steam (100 degrees C). An increase in sensitivity was observed when heat-injured cells were plated on glucose-supplemented YMA at an aw of 0.880 compared with aws of 0.933 and 0.998. Colonies which developed from unheated and heated cells on YMA at aws of 0.998 and 0.933 generally exceeded 0.5 mm in diameter within 3.5 to 4 days of incubation at 25 degrees C, whereas colonies formed on YMA at an aw of 0.880 typically did not exceed 0.5 mm in diameter until after 5.5 to 6.5 days of incubation. The number of colonies exceeding 0.5 mm in diameter which were formed by heat-injured cells on YMA at an aw of 0.880 was 2 to 3 logs less than the total number of colonies detected, i.e., on YMA at an aw of 0.933 and using no limits of exclusion based on colony diameter. A substantial portion of cells which survived heat treatment were sublethally injured as evidenced by increased sensitivity to a suboptimum aw (0.880). In no instance was recovery of Z. rouxii significantly affected by medium sterilization procedure when glucose or sorbitol was used as the aw-suppressing solute.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2403251

  1. Colony formation by sublethally heat-injured Zygosaccharomyces rouxii as affected by solutes in the recovery medium and procedure for sterilizing medium.

    Science.gov (United States)

    Golden, D A; Beuchat, L R

    1990-08-01

    Recovery and colony formation by healthy and sublethally heat-injured cells of Zygosaccharomyces rouxii as influenced by the procedure for sterilizing recovery media (YM agar [YMA], wort agar, cornmeal agar, and oatmeal agar) were investigated. Media were supplemented with various concentrations of glucose, sucrose, glycerol, or sorbitol and sterilized by autoclaving (110 degrees C, 15 min) and by repeated treatment with steam (100 degrees C). An increase in sensitivity was observed when heat-injured cells were plated on glucose-supplemented YMA at an aw of 0.880 compared with aws of 0.933 and 0.998. Colonies which developed from unheated and heated cells on YMA at aws of 0.998 and 0.933 generally exceeded 0.5 mm in diameter within 3.5 to 4 days of incubation at 25 degrees C, whereas colonies formed on YMA at an aw of 0.880 typically did not exceed 0.5 mm in diameter until after 5.5 to 6.5 days of incubation. The number of colonies exceeding 0.5 mm in diameter which were formed by heat-injured cells on YMA at an aw of 0.880 was 2 to 3 logs less than the total number of colonies detected, i.e., on YMA at an aw of 0.933 and using no limits of exclusion based on colony diameter. A substantial portion of cells which survived heat treatment were sublethally injured as evidenced by increased sensitivity to a suboptimum aw (0.880). In no instance was recovery of Z. rouxii significantly affected by medium sterilization procedure when glucose or sorbitol was used as the aw-suppressing solute.(ABSTRACT TRUNCATED AT 250 WORDS)

  2. Haemopoietic progenitor cells in human peripheral blood

    International Nuclear Information System (INIS)

    Zwaan, F.E.

    1980-01-01

    The purpose of the investigation reported is to purify haemopoietic progenitor cells from human peripheral blood using density gradient centrifugation in order to isolate a progenitor cell fraction without immunocompetent cells. The purification technique of peripheral blood flow colony forming unit culture (CFU-c) by means of density gradient centrifugation and a combined depletion of various rosettes is described. The results of several 'in vitro' characteristics of purified CFU-c suspensions and of the plasma clot diffusion chamber culture technique are presented. Irradiation studies revealed that for both human bone marrow and peripheral blood the CFU-c were less radioresistant than clusters. Elimination of monocytes (and granulocytes) from the test suspensions induced an alteration in radiosensitivity pararmeters. The results obtained with the different techniques are described by analysing peripheral progenitor cell activity in myeloproliferative disorders. (Auth.)

  3. Forms of Memory in Post-colonial Australia

    Directory of Open Access Journals (Sweden)

    Lyn McCredden

    2009-06-01

    Full Text Available there are many forms of memory in post-colonial Australia, and many kinds of haunting. This paper investigates the poetry of contemporary Indigenous poets Sam Wagan Watson and Tony Birch, and reads the script of the Federal Government’s February 2008 Apology to the Stolen Generations, asking how and why the nation should be haunted – historically and imaginatively - into the future.

  4. Detachment of Chain-Forming Neuroblasts by Fyn-Mediated Control of cell-cell Adhesion in the Postnatal Brain.

    Science.gov (United States)

    Fujikake, Kazuma; Sawada, Masato; Hikita, Takao; Seto, Yayoi; Kaneko, Naoko; Herranz-Pérez, Vicente; Dohi, Natsuki; Homma, Natsumi; Osaga, Satoshi; Yanagawa, Yuchio; Akaike, Toshihiro; García-Verdugo, Jose Manuel; Hattori, Mitsuharu; Sobue, Kazuya; Sawamoto, Kazunobu

    2018-05-09

    In the rodent olfactory system, neuroblasts produced in the ventricular-subventricular zone of the postnatal brain migrate tangentially in chain-like cell aggregates toward the olfactory bulb (OB) through the rostral migratory stream (RMS). After reaching the OB, the chains are dissociated and the neuroblasts migrate individually and radially toward their final destination. The cellular and molecular mechanisms controlling cell-cell adhesion during this detachment remain unclear. Here we report that Fyn, a nonreceptor tyrosine kinase, regulates the detachment of neuroblasts from chains in the male and female mouse OB. By performing chemical screening and in vivo loss-of-function and gain-of-function experiments, we found that Fyn promotes somal disengagement from the chains and is involved in neuronal migration from the RMS into the granule cell layer of the OB. Fyn knockdown or Dab1 (disabled-1) deficiency caused p120-catenin to accumulate and adherens junction-like structures to be sustained at the contact sites between neuroblasts. Moreover, a Fyn and N-cadherin double-knockdown experiment indicated that Fyn regulates the N-cadherin-mediated cell adhesion between neuroblasts. These results suggest that the Fyn-mediated control of cell-cell adhesion is critical for the detachment of chain-forming neuroblasts in the postnatal OB. SIGNIFICANCE STATEMENT In the postnatal brain, newly born neurons (neuroblasts) migrate in chain-like cell aggregates toward their destination, where they are dissociated into individual cells and mature. The cellular and molecular mechanisms controlling the detachment of neuroblasts from chains are not understood. Here we show that Fyn, a nonreceptor tyrosine kinase, promotes the somal detachment of neuroblasts from chains, and that this regulation is critical for the efficient migration of neuroblasts to their destination. We further show that Fyn and Dab1 (disabled-1) decrease the cell-cell adhesion between chain-forming neuroblasts

  5. Sigma-2 ligands and PARP inhibitors synergistically trigger cell death in breast cancer cells

    International Nuclear Information System (INIS)

    McDonald, Elizabeth S.; Mankoff, Julia; Makvandi, Mehran; Chu, Wenhua; Chu, Yunxiang; Mach, Robert H.; Zeng, Chenbo

    2017-01-01

    The sigma-2 receptor is overexpressed in proliferating cells compared to quiescent cells and has been used as a target for imaging solid tumors by positron emission tomography. Recent work has suggested that the sigma-2 receptor may also be an effective therapeutic target for cancer therapy. Poly (ADP-ribose) polymerase (PARP) is a family of enzymes involved in DNA damage response. In this study, we looked for potential synergy of cytotoxicity between PARP inhibitors and sigma-2 receptor ligands in breast cancer cell lines. We showed that the PARP inhibitor, YUN3-6, sensitized mouse breast cancer cell line, EMT6, to sigma-2 receptor ligand (SV119, WC-26, and RHM-138) induced cell death determined by cell viability assay and colony forming assay. The PARP inhibitor, olaparib, sensitized tumor cells to a different sigma-2 receptor ligand SW43-induced apoptosis and cell death in human triple negative cell line, MDA-MB-231. Olaparib inhibited PARP activity and cell proliferation, and arrested cells in G2/M phase of the cell cycle in MDA-MB-231 cells. Subsequently cells became sensitized to SW43 induced cell death. In conclusion, the combination of sigma-2 receptor ligands and PARP inhibitors appears to hold promise for synergistically triggering cell death in certain types of breast cancer cells and merits further investigation. - Highlights: • PARPi, YUN3-6 and olaparib, and σ2 ligands, SV119 and SW43, were evaluated. • Mouse and human breast cancer cells, EMT6 and MDA-MB-231 respectively, were used. • YUN3-6 and SV119 synergistically triggered cell death in EMT6 cells. • Olaparib and SW43 additively triggered cell death in MDA-MB-231 cells. • Olaparib arrested cells in G2/M in MDA-MB-231 cells.

  6. Yeast Colonies: A Model for Studies of Aging, Environmental Adaptation, and Longevity

    OpenAIRE

    Libuše Váchová; Michal Čáp; Zdena Palková

    2012-01-01

    When growing on solid surfaces, yeast, like other microorganisms, develops organized multicellular populations (colonies and biofilms) that are composed of differentiated cells with specialized functions. Life within these populations is a prevalent form of microbial existence in natural settings that provides the cells with capabilities to effectively defend against environmental attacks as well as efficiently adapt and survive long periods of starvation and other stresses. Under such circum...

  7. Abiotic factors in colony formation: effects of nutrition and light on extracellular polysaccharide production and cell aggregates of Microcystis aeruginosa

    Science.gov (United States)

    Yang, Zhen; Kong, Fanxiang

    2013-07-01

    Colony morphology is important for Microcystis to sustain a competitive advantage in eutrophic lakes. The mechanism of colony formation in Microcystis is currently unclear. Extracellular polysaccharide (EPS) has been reported to play an important role in cell aggregate formation of some phytoplankton. Microcystis aeruginosa was cultivated under varied abiotic conditions, including different nutrient, light, and temperature conditions, to investigate their effects on EPS production and morphological change. The results show that nutrient concentration and light intensity have great effects on EPS productionin M. aeruginosa. There was a considerable increase in EPS production after M. aeruginosa was cultivated in adjusted culture conditions similar to those present in the field (28.9 mg C/L, 1.98 mg N/L, 0.65 mg P/L, light intensity: 100 μmol/(m2 · s)). These results indicate that abiotic factors might be one of the triggers for colony formation in Microcystis.

  8. Heterogeneity of osteosarcoma cell lines led to variable responses in reprogramming.

    Science.gov (United States)

    Choong, Pei Feng; Teh, Hui Xin; Teoh, Hoon Koon; Ong, Han Kiat; Choo, Kong Bung; Sugii, Shigeki; Cheong, Soon Keng; Kamarul, Tunku

    2014-01-01

    Four osteosarcoma cell lines, Saos-2, MG-63, G-292 and U-2 OS, were reprogrammed to pluripotent state using Yamanaka factors retroviral transduction method. Embryonic stem cell (ESC)-like clusters started to appear between 15 to 20 days post transduction. Morphology of the colonies resembled that of ESC colonies with defined border and tightly-packed cells. The reprogrammed sarcomas expressed alkaline phosphatase and pluripotency markers, OCT4, SSEA4, TRA-1-60 and TRA-1-81, as in ESC up to Passage 15. All reprogrammed sarcomas could form embryoid body-like spheres when cultured in suspension in a low attachment dish for up to 10 days. Further testing on the directed differentiation capacity of the reprogrammed sarcomas showed all four reprogrammed sarcoma lines could differentiate into adipocytes while reprogrammed Saos-2-REP, MG-63-REP and G-292-REP could differentiate into osteocytes. Among the 4 osteosarcoma cell lines, U-2 OS reported the highest transduction efficiency but recorded the lowest reprogramming stability under long term culture. Thus, there may be intrinsic differences governing the variable responses of osteosarcoma cell lines towards reprogramming and long term culture effect of the reprogrammed cells. This is a first report to associate intrinsic factors in different osteosarcoma cell lines with variable reprogramming responses and effects on the reprogrammed cells after prolonged culture.

  9. Heterogeneity of Osteosarcoma Cell Lines Led to Variable Responses in Reprogramming

    Science.gov (United States)

    Choong, Pei Feng; Teh, Hui Xin; Teoh, Hoon Koon; Ong, Han Kiat; Choo, Kong Bung; Sugii, Shigeki; Cheong, Soon Keng; Kamarul, Tunku

    2014-01-01

    Four osteosarcoma cell lines, Saos-2, MG-63, G-292 and U-2 OS, were reprogrammed to pluripotent state using Yamanaka factors retroviral transduction method. Embryonic stem cell (ESC)-like clusters started to appear between 15 to 20 days post transduction. Morphology of the colonies resembled that of ESC colonies with defined border and tightly-packed cells. The reprogrammed sarcomas expressed alkaline phosphatase and pluripotency markers, OCT4, SSEA4, TRA-1-60 and TRA-1-81, as in ESC up to Passage 15. All reprogrammed sarcomas could form embryoid body-like spheres when cultured in suspension in a low attachment dish for up to 10 days. Further testing on the directed differentiation capacity of the reprogrammed sarcomas showed all four reprogrammed sarcoma lines could differentiate into adipocytes while reprogrammed Saos-2-REP, MG-63-REP and G-292-REP could differentiate into osteocytes. Among the 4 osteosarcoma cell lines, U-2 OS reported the highest transduction efficiency but recorded the lowest reprogramming stability under long term culture. Thus, there may be intrinsic differences governing the variable responses of osteosarcoma cell lines towards reprogramming and long term culture effect of the reprogrammed cells. This is a first report to associate intrinsic factors in different osteosarcoma cell lines with variable reprogramming responses and effects on the reprogrammed cells after prolonged culture. PMID:25170299

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

    International Nuclear Information System (INIS)

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

    2007-01-01

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

  11. Factors controlling the recirculation of haematopoietic stem cells

    International Nuclear Information System (INIS)

    Petrov, R.V.; Khaitov, R.M.; Alejnikova, N.V.; Gulak, L.V.

    1976-01-01

    Influence of thymectomy on the rate of migration and differentiation of haematopoietic stem cells from a shielded part of the bone marrow has been studied on mice X-irradiated with a lethal dose. Inhibition of the migration rate and delay in differentiation of stem cells into colonies of granuloid type have been detected in the thymectomized mice. Transplantation of syngeneic cells of the thymus or lymph nodes to thymectomized mice increases the number of colonies in the spleen and restores the routine way of differentiation of haematopoietic stem cells. It is concluded that the processes of migration and differentiation of haematopoietic stem cells are thymus-dependent

  12. Granulocyte colony-stimulating factor mobilizes dormant hematopoietic stem cells without proliferation in mice.

    Science.gov (United States)

    Bernitz, Jeffrey M; Daniel, Michael G; Fstkchyan, Yesai S; Moore, Kateri

    2017-04-06

    Granulocyte colony-stimulating factor (G-CSF) is used clinically to treat leukopenia and to enforce hematopoietic stem cell (HSC) mobilization to the peripheral blood (PB). However, G-CSF is also produced in response to infection, and excessive exposure reduces HSC repopulation capacity. Previous work has shown that dormant HSCs contain all the long-term repopulation potential in the bone marrow (BM), and that as HSCs accumulate a divisional history, they progressively lose regenerative potential. As G-CSF treatment also induces HSC proliferation, we sought to examine whether G-CSF-mediated repopulation defects are a result of increased proliferative history. To do so, we used an established H2BGFP label retaining system to track HSC divisions in response to G-CSF. Our results show that dormant HSCs are preferentially mobilized to the PB on G-CSF treatment. We find that this mobilization does not result in H2BGFP label dilution of dormant HSCs, suggesting that G-CSF does not stimulate dormant HSC proliferation. Instead, we find that proliferation within the HSC compartment is restricted to CD41-expressing cells that function with short-term, and primarily myeloid, regenerative potential. Finally, we show CD41 expression is up-regulated within the BM HSC compartment in response to G-CSF treatment. This emergent CD41 Hi HSC fraction demonstrates no observable engraftment potential, but directly matures into megakaryocytes when placed in culture. Together, our results demonstrate that dormant HSCs mobilize in response to G-CSF treatment without dividing, and that G-CSF-mediated proliferation is restricted to cells with limited regenerative potential found within the HSC compartment. © 2017 by The American Society of Hematology.

  13. Mathematical Modeling the Geometric Regularity in Proteus Mirabilis Colonies

    Science.gov (United States)

    Zhang, Bin; Jiang, Yi; Minsu Kim Collaboration

    Proteus Mirabilis colony exhibits striking spatiotemporal regularity, with concentric ring patterns with alternative high and low bacteria density in space, and periodicity for repetition process of growth and swarm in time. We present a simple mathematical model to explain the spatiotemporal regularity of P. Mirabilis colonies. We study a one-dimensional system. Using a reaction-diffusion model with thresholds in cell density and nutrient concentration, we recreated periodic growth and spread patterns, suggesting that the nutrient constraint and cell density regulation might be sufficient to explain the spatiotemporal periodicity in P. Mirabilis colonies. We further verify this result using a cell based model.

  14. Generation of Megakaryocytes and Platelets from Human Pluripotent Stem Cells.

    Science.gov (United States)

    Pick, Marjorie

    2016-01-01

    Human pluripotent stem cells (hPSC) have the potential to produce any tissue type in the body and thus represent a source of cells for regenerative medicine. Here we have shown that human platelets can be produced from embryonic or induced pluripotent stem cells in a defined culture system. We describe a serum- and feeder-free culture system that enabled the generation of megakaryocyte (Mk) progenitors and functional platelets from hPSCs. After 13 days the differentiated population included precursor cells that formed colonies containing differentiated Mks, and after 20 days these Mks were able to fragment into platelet-like particles that were functional. This protocol represents an important step towards the generation of human platelets for therapeutic use.

  15. Physical Forces Modulate Oxidative Status and Stress Defense Meditated Metabolic Adaptation of Yeast Colonies: Spaceflight and Microgravity Simulations

    Science.gov (United States)

    Hammond, Timothy G.; Allen, Patricia L.; Gunter, Margaret A.; Chiang, Jennifer; Giaever, Guri; Nislow, Corey; Birdsall, Holly H.

    2018-05-01

    Baker's yeast ( Saccharomyces cerevisiae) has broad genetic homology to human cells. Although typically grown as 1-2mm diameter colonies under certain conditions yeast can form very large (10 + mm in diameter) or `giant' colonies on agar. Giant yeast colonies have been used to study diverse biomedical processes such as cell survival, aging, and the response to cancer pharmacogenomics. Such colonies evolve dynamically into complex stratified structures that respond differentially to environmental cues. Ammonia production, gravity driven ammonia convection, and shear defense responses are key differentiation signals for cell death and reactive oxygen system pathways in these colonies. The response to these signals can be modulated by experimental interventions such as agar composition, gene deletion and application of pharmaceuticals. In this study we used physical factors including colony rotation and microgravity to modify ammonia convection and shear stress as environmental cues and observed differences in the responses of both ammonia dependent and stress response dependent pathways We found that the effects of random positioning are distinct from rotation. Furthermore, both true and simulated microgravity exacerbated both cellular redox responses and apoptosis. These changes were largely shear-response dependent but each model had a unique response signature as measured by shear stress genes and the promoter set which regulates them These physical techniques permitted a graded manipulation of both convection and ammonia signaling and are primed to substantially contribute to our understanding of the mechanisms of drug action, cell aging, and colony differentiation.

  16. Physical Forces Modulate Oxidative Status and Stress Defense Meditated Metabolic Adaptation of Yeast Colonies: Spaceflight and Microgravity Simulations

    Science.gov (United States)

    Hammond, Timothy G.; Allen, Patricia L.; Gunter, Margaret A.; Chiang, Jennifer; Giaever, Guri; Nislow, Corey; Birdsall, Holly H.

    2017-12-01

    Baker's yeast (Saccharomyces cerevisiae) has broad genetic homology to human cells. Although typically grown as 1-2mm diameter colonies under certain conditions yeast can form very large (10 + mm in diameter) or `giant' colonies on agar. Giant yeast colonies have been used to study diverse biomedical processes such as cell survival, aging, and the response to cancer pharmacogenomics. Such colonies evolve dynamically into complex stratified structures that respond differentially to environmental cues. Ammonia production, gravity driven ammonia convection, and shear defense responses are key differentiation signals for cell death and reactive oxygen system pathways in these colonies. The response to these signals can be modulated by experimental interventions such as agar composition, gene deletion and application of pharmaceuticals. In this study we used physical factors including colony rotation and microgravity to modify ammonia convection and shear stress as environmental cues and observed differences in the responses of both ammonia dependent and stress response dependent pathways We found that the effects of random positioning are distinct from rotation. Furthermore, both true and simulated microgravity exacerbated both cellular redox responses and apoptosis. These changes were largely shear-response dependent but each model had a unique response signature as measured by shear stress genes and the promoter set which regulates them These physical techniques permitted a graded manipulation of both convection and ammonia signaling and are primed to substantially contribute to our understanding of the mechanisms of drug action, cell aging, and colony differentiation.

  17. Colony stimulating factor 1 receptor inhibition delays recurrence of glioblastoma after radiation by altering myeloid cell recruitment and polarization

    Science.gov (United States)

    Stafford, Jason H.; Hirai, Takahisa; Deng, Lei; Chernikova, Sophia B.; Urata, Kimiko; West, Brian L.; Brown, J. Martin

    2016-01-01

    Background Glioblastoma (GBM) may initially respond to treatment with ionizing radiation (IR), but the prognosis remains extremely poor because the tumors invariably recur. Using animal models, we previously showed that inhibiting stromal cell–derived factor 1 signaling can prevent or delay GBM recurrence by blocking IR-induced recruitment of myeloid cells, specifically monocytes that give rise to tumor-associated macrophages. The present study was aimed at determining if inhibiting colony stimulating factor 1 (CSF-1) signaling could be used as an alternative strategy to target pro-tumorigenic myeloid cells recruited to irradiated GBM. Methods To inhibit CSF-1 signaling in myeloid cells, we used PLX3397, a small molecule that potently inhibits the tyrosine kinase activity of the CSF-1 receptor (CSF-1R). Combined IR and PLX3397 therapy was compared with IR alone using 2 different human GBM intracranial xenograft models. Results GBM xenografts treated with IR upregulated CSF-1R ligand expression and increased the number of CD11b+ myeloid-derived cells in the tumors. Treatment with PLX3397 both depleted CD11b+ cells and potentiated the response of the intracranial tumors to IR. Median survival was significantly longer for mice receiving combined therapy versus IR alone. Analysis of myeloid cell differentiation markers indicated that CSF-1R inhibition prevented IR-recruited monocyte cells from differentiating into immunosuppressive, pro-angiogenic tumor-associated macrophages. Conclusion CSF-1R inhibition may be a promising strategy to improve GBM response to radiotherapy. PMID:26538619

  18. Pretransplant mobilization with granulocyte colony-stimulating factor improves B-cell reconstitution by lentiviral vector gene therapy in SCID-X1 mice.

    Science.gov (United States)

    Huston, Marshall W; Riegman, Adriaan R A; Yadak, Rana; van Helsdingen, Yvette; de Boer, Helen; van Til, Niek P; Wagemaker, Gerard

    2014-10-01

    Hematopoietic stem cell (HSC) gene therapy is a demonstrated effective treatment for X-linked severe combined immunodeficiency (SCID-X1), but B-cell reconstitution and function has been deficient in many of the gene therapy treated patients. Cytoreductive preconditioning is known to improve HSC engraftment, but in general it is not considered for SCID-X1 since the poor health of most of these patients at diagnosis and the risk of toxicity preclude the conditioning used in standard bone marrow stem cell transplantation. We hypothesized that mobilization of HSC by granulocyte colony-stimulating factor (G-CSF) should create temporary space in bone marrow niches to improve engraftment and thereby B-cell reconstitution. In the present pilot study supplementing our earlier preclinical evaluation (Huston et al., 2011), Il2rg(-/-) mice pretreated with G-CSF were transplanted with wild-type lineage negative (Lin(-)) cells or Il2rg(-/-) Lin(-) cells transduced with therapeutic IL2RG lentiviral vectors. Mice were monitored for reconstitution of lymphocyte populations, level of donor cell chimerism, and antibody responses as compared to 2 Gy total body irradiation (TBI), previously found effective in promoting B-cell reconstitution. The results demonstrate that G-CSF promotes B-cell reconstitution similar to low-dose TBI and provides proof of principle for an alternative approach to improve efficacy of gene therapy in SCID patients without adverse effects associated with cytoreductive conditioning.

  19. Bone marrow cells other than stem cells seed the bone marrow after rescue transfusion of fatally irradiated mice

    International Nuclear Information System (INIS)

    Cronkite, E.P.; Inoue, T.; Bullis, J.E.

    1987-01-01

    In a previous publication, iodinated deoxyuridine ( 125 IUdR) incorporation data were interpreted as indicating that spleen colony-forming units (CFU-S) in DNA synthesis preferentially seeded bone marrow. In the present studies, the CFU-S content of marrow from irradiated, bone-marrow transfused mice was directly determined. Pretreatment of the transfused cells with cytocidal tritiated thymidine resulted in an insignificant diminution in CFU-S content when compared with nontritiated thymidine pretreatment, implying that there is no preferential seeding. The 125 IUdR incorporation data have been reinterpreted as being a result of the proliferation of other progenitor cells present that have seeded the bone marrow

  20. Possible association between stem-like hallmark and radioresistance in human cervical carcinoma cells.

    Science.gov (United States)

    Kumazawa, Shoko; Kajiyama, Hiroaki; Umezu, Tomokazu; Mizuno, Mika; Suzuki, Shiro; Yamamoto, Eiko; Mitsui, Hiroko; Sekiya, Ryuichiro; Shibata, Kiyosumi; Kikkawa, Fumitaka

    2014-05-01

    We aimed to investigate the possibility of an association between a stem-like hallmark and radiotherapeutic sensitivity in human cervical carcinoma cells. Side-population (SP) cells and non-SP (NSP) cells in HeLa cells were isolated using flow cytometry and Hoechst 33342 efflux. We performed Western blot analysis to evaluate the expression of stem cell markers (CXCR4, Oct3/4, CD133, and SOX2) and apoptosis markers after irradiation. In addition, SP and NSP cells were injected into nude mice and we assessed subcutaneous tumor formation. To examine tolerance of irradiation, colony formation and apoptosis change were confirmed in the SP and NSP cells. SP cells showed a higher expression of CXCR4, Oct3/4, CD133, and SOX2 than NSP cells. The colony size of SP cells cultured on non-coated dishes was larger than that of NSP cells, and NSP cells were easily induced to undergo apoptosis. SP cells tended to form spheroids and showed a higher level of tumorigenicity compared with NSP cells. In addition, nude mice inoculated with SP cells showed greater tumor growth compared with NSP cells. SP cells showed a higher tumorigenicity and lower apoptotic potential, leading to enhanced radiotolerance. Tumor SP cells showed higher-level stem-cell-like characters and radioresistance than NSP cells. SP cells may be useful for new therapeutic approaches for radiation-resistant cervical cancer. © 2014 The Authors. Journal of Obstetrics and Gynaecology Research © 2014 Japan Society of Obstetrics and Gynecology.

  1. PDZ domain-binding motif of human T-cell leukemia virus type 1 Tax oncoprotein augments the transforming activity in a rat fibroblast cell line

    International Nuclear Information System (INIS)

    Hirata, Akira; Higuchi, Masaya; Niinuma, Akiko; Ohashi, Minako; Fukushi, Masaya; Oie, Masayasu; Akiyama, Tetsu; Tanaka, Yuetsu; Gejyo, Fumitake; Fujii, Masahiro

    2004-01-01

    While human T-cell leukemia virus type 1 (HTLV-1) is associated with the development of adult T-cell leukemia (ATL), HTLV-2 has not been reported to be associated with such malignant leukemias. HTLV-1 Tax1 oncoprotein transforms a rat fibroblast cell line (Rat-1) to form multiple large colonies in soft agar, and this activity is much greater than that of HTLV-2 Tax2. We have demonstrated here that the increased number of transformed colonies induced by Tax1 relative to Tax2 was mediated by a PDZ domain-binding motif (PBM) in Tax1, which is absent in Tax2. Tax1 PBM mediated the interaction of Tax1 with the discs large (Dlg) tumor suppressor containing PDZ domains, and the interaction correlated well with the transforming activities of Tax1 and the mutants. Through this interaction, Tax1 altered the subcellular localization of Dlg from the detergent-soluble to the detergent-insoluble fraction in a fibroblast cell line as well as in HTLV-1-infected T-cell lines. These results suggest that the interaction of Tax1 with PDZ domain protein(s) is critically involved in the transforming activity of Tax1, the activity of which may be a crucial factor in malignant transformation of HTLV-1-infected cells in vivo

  2. Aldehyde dehydrogenase activity selects for the holoclone phenotype in prostate cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Doherty, R.E.; Haywood-Small, S.L. [Biomedical Research Centre, Sheffield Hallam University, Sheffield S1 1WB (United Kingdom); Sisley, K. [Department of Oncology, Academic Unit of Ophthalmology and Orthopties, University of Sheffield, Sheffield S10 2RX (United Kingdom); Cross, N.A., E-mail: n.cross@shu.ac.uk [Biomedical Research Centre, Sheffield Hallam University, Sheffield S1 1WB (United Kingdom)

    2011-11-04

    Highlights: Black-Right-Pointing-Pointer Isolated ALDH{sup Hi} PC3 cells preferentially form primitive holoclone-type colonies. Black-Right-Pointing-Pointer Primitive holoclone colonies are predominantly ALDH{sup Lo} but contain rare ALDH{sup Hi} cells. Black-Right-Pointing-Pointer Holoclone-forming cells are not restricted to the ALDH{sup Hi} population. Black-Right-Pointing-Pointer ALDH phenotypic plasticity occurs in PC3 cells (ALDH{sup Lo} to ALDH{sup Hi} and vice versa). Black-Right-Pointing-Pointer ALDH{sup Hi} cells are observed but very rare in PC3 spheroids grown in stem cell medium. -- Abstract: Aldehyde dehydrogenase 1 (ALDH) activity is considered to be a marker of cancer stem cells (CSCs) in many tumour models, since these cells are more proliferative and tumourigenic than ALDH{sup Lo} cells in experimental models. However it is unclear whether all CSC-like cells are within the ALDH{sup Hi} population, or whether all ALDH{sup Hi} cells are highly proliferative and tumourigenic. The ability to establish a stem cell hierarchy in vitro, whereby sub-populations of cells have differing proliferative and differentiation capacities, is an alternate indication of the presence of stem cell-like populations within cell lines. In this study, we have examined the interaction between ALDH status and the ability to establish a stem cell hierarchy in PC3 prostate cancer cells. We demonstrate that PC3 cells contain a stem cell hierarchy, and isolation of ALDH{sup Hi} cells enriches for the most primitive holoclone population, however holoclone formation is not restricted to ALDH{sup Hi} cells. In addition, we show that ALDH activity undergoes phenotypic plasticity, since the ALDH{sup Lo} population can develop ALDH{sup Hi} populations comparable to parental cells within 2 weeks in culture. Furthermore, we show that the majority of ALDH{sup Hi} cells are found within the least primitive paraclone population, which is circumvented by culturing PC3 cells as spheroids in

  3. Micro-patterned agarose gel devices for single-cell high-throughput microscopy of E. coli cells.

    Science.gov (United States)

    Priest, David G; Tanaka, Nobuyuki; Tanaka, Yo; Taniguchi, Yuichi

    2017-12-21

    High-throughput microscopy of bacterial cells elucidated fundamental cellular processes including cellular heterogeneity and cell division homeostasis. Polydimethylsiloxane (PDMS)-based microfluidic devices provide advantages including precise positioning of cells and throughput, however device fabrication is time-consuming and requires specialised skills. Agarose pads are a popular alternative, however cells often clump together, which hinders single cell quantitation. Here, we imprint agarose pads with micro-patterned 'capsules', to trap individual cells and 'lines', to direct cellular growth outwards in a straight line. We implement this micro-patterning into multi-pad devices called CapsuleHotel and LineHotel for high-throughput imaging. CapsuleHotel provides ~65,000 capsule structures per mm 2 that isolate individual Escherichia coli cells. In contrast, LineHotel provides ~300 line structures per mm that direct growth of micro-colonies. With CapsuleHotel, a quantitative single cell dataset of ~10,000 cells across 24 samples can be acquired and analysed in under 1 hour. LineHotel allows tracking growth of > 10 micro-colonies across 24 samples simultaneously for up to 4 generations. These easy-to-use devices can be provided in kit format, and will accelerate discoveries in diverse fields ranging from microbiology to systems and synthetic biology.

  4. Stress Management in Cyst-Forming Free-Living Protists: Programmed Cell Death and/or Encystment

    Science.gov (United States)

    Khan, Naveed Ahmed; Iqbal, Junaid

    2015-01-01

    In the face of harsh conditions and given a choice, a cell may (i) undergo programmed cell death, (ii) transform into a cancer cell, or (iii) enclose itself into a cyst form. In metazoans, the available evidence suggests that cellular machinery exists only to execute or avoid programmed cell death, while the ability to form a cyst was either lost or never developed. For cyst-forming free-living protists, here we pose the question whether the ability to encyst was gained at the expense of the programmed cell death or both functions coexist to counter unfavorable environmental conditions with mutually exclusive phenotypes. PMID:25648302

  5. Stress Management in Cyst-Forming Free-Living Protists: Programmed Cell Death and/or Encystment

    Directory of Open Access Journals (Sweden)

    Naveed Ahmed Khan

    2015-01-01

    Full Text Available In the face of harsh conditions and given a choice, a cell may (i undergo programmed cell death, (ii transform into a cancer cell, or (iii enclose itself into a cyst form. In metazoans, the available evidence suggests that cellular machinery exists only to execute or avoid programmed cell death, while the ability to form a cyst was either lost or never developed. For cyst-forming free-living protists, here we pose the question whether the ability to encyst was gained at the expense of the programmed cell death or both functions coexist to counter unfavorable environmental conditions with mutually exclusive phenotypes.

  6. Local behavioral rules sustain the cell allocation pattern in the combs of honey bee colonies (Apis mellifera).

    Science.gov (United States)

    Montovan, Kathryn J; Karst, Nathaniel; Jones, Laura E; Seeley, Thomas D

    2013-11-07

    In the beeswax combs of honey bees, the cells of brood, pollen, and honey have a consistent spatial pattern that is sustained throughout the life of a colony. This spatial pattern is believed to emerge from simple behavioral rules that specify how the queen moves, where foragers deposit honey/pollen and how honey/pollen is consumed from cells. Prior work has shown that a set of such rules can explain the formation of the allocation pattern starting from an empty comb. We show that these rules cannot maintain the pattern once the brood start to vacate their cells, and we propose new, biologically realistic rules that better sustain the observed allocation pattern. We analyze the three resulting models by performing hundreds of simulation runs over many gestational periods and a wide range of parameter values. We develop new metrics for pattern assessment and employ them in analyzing pattern retention over each simulation run. Applied to our simulation results, these metrics show alteration of an accepted model for honey/pollen consumption based on local information can stabilize the cell allocation pattern over time. We also show that adding global information, by biasing the queen's movements towards the center of the comb, expands the parameter regime over which pattern retention occurs. © 2013 Published by Elsevier Ltd. All rights reserved.

  7. Comparison of Preterm and Term Wharton's Jelly-Derived Mesenchymal Stem Cell Properties in Different Oxygen Tensions.

    Science.gov (United States)

    Balgi-Agarwal, Saloni; Winter, Caitlyn; Corral, Alexis; Mustafa, Shamimunisa B; Hornsby, Peter; Moreira, Alvaro

    2018-06-27

    Mesenchymal stem cells (MSCs) have shown promise as therapeutic agents in treating morbidities associated with premature birth. MSCs derived from the human umbilical cord are easy to isolate and have low immunogenicity and a robust ability to secrete paracrine factors. To date, there are no studies evaluating preterm versus term umbilical cord tissue-derived MSCs. Therefore, our aim was twofold: (1) to compare stem cell properties in preterm versus term MSCs and (2) to examine the impact of oxygen tension on stem cell behavior. Umbilical cord tissue was obtained from 5 preterm and 5 term neonates. The cells were isolated and characterized as MSCs in accordance with the International Society for Cellular Therapy. We exposed MSCs to different oxygen tensions to examine the impact of environmental factors on cell performance. We studied the following stem cell properties: (i) motility, (ii) proliferation, (iii) senescence, (iv) cell viability, (v) colony-forming unit efficiency, and (vi) inflammatory cytokine expression. Under normoxia (21% O2), cells from preterm and term infants had similar properties. Under hypoxic conditions (1% O2), term MSCs had better cell proliferation; however, cells exposed to hyperoxia (90% O2) had the slowest motility and lowest cell viability (p cytokine expression between the groups. The term cells demonstrated more colony-forming efficiency than the preterm cells. In sum, our preliminary findings suggest that MSCs derived from term and preterm umbilical cords have similar characteristics, offering the potential of future autologous/allogeneic MSC transplants in neonates. © 2018 S. Karger AG, Basel.

  8. Musashi1 modulates cell proliferation genes in the medulloblastoma cell line Daoy

    Directory of Open Access Journals (Sweden)

    Hung Jaclyn Y

    2008-09-01

    Full Text Available Abstract Background Musashi1 (Msi1 is an RNA binding protein with a central role during nervous system development and stem cell maintenance. High levels of Msi1 have been reported in several malignancies including brain tumors thereby associating Msi1 and cancer. Methods We used the human medulloblastoma cell line Daoy as model system in this study to knock down the expression of Msi1 and determine the effects upon soft agar growth and neurophere formation. Quantitative RT-PCR was conducted to evaluate the expression of cell proliferation, differentiation and survival genes in Msi1 depleted Daoy cells. Results We observed that MSI1 expression was elevated in Daoy cells cultured as neurospheres compared to those grown as monolayer. These data indicated that Msi1 might be involved in regulating proliferation in cancer cells. Here we show that shRNA mediated Msi1 depletion in Daoy cells notably impaired their ability to form colonies in soft agar and to grow as neurospheres in culture. Moreover, differential expression of a group of Notch, Hedgehog and Wnt pathway related genes including MYCN, FOS, NOTCH2, SMO, CDKN1A, CCND2, CCND1, and DKK1, was also found in the Msi1 knockdown, demonstrating that Msi1 modulated the expression of a subset of cell proliferation, differentiation and survival genes in Daoy. Conclusion Our data suggested that Msi1 may promote cancer cell proliferation and survival as its loss seems to have a detrimental effect in the maintenance of medulloblastoma cancer cells. In this regard, Msi1 might be a positive regulator of tumor progression and a potential target for therapy.

  9. Phototransfection of mammalian cells using femtosecond laser pulses: optimization and applicability to stem cell differentiation

    CSIR Research Space (South Africa)

    Mthunzi, P

    2010-07-01

    Full Text Available phototransfection. Extending previous studies, we show that femtosecond lasers can be used to phototransfect a range of different cell lines, and specifically that this novel technology can also transfect mouse embryonic stem cell colonies with 25% efficiency...

  10. Vascular budding in Symplegma brakenhielmi and the evolution of coloniality in styelid ascidians.

    Science.gov (United States)

    Gutierrez, Stefania; Brown, Federico D

    2017-03-15

    Individuals of colonial animals (e.g. zooids) are in continuous turnover. In ascidians colonial or solitary species have evolved by convergence multiple times. Colonial Botryllus and Botrylloides are well-studied genera that exhibit colony-wide developmental mechanisms that regulate synchronous and orchestrated cycles of budding and turnover of zooids. The origins of modular developmental mechanisms that facilitated the evolution of coloniality in this group remain unclear. To reconstruct ancestral states of coloniality we studied Symplegma brakenhielmi, a sister taxon of the botryllids. S. brakenhielmi zooids are embedded in a common tunic and present a similar vascular system as the botrylloides, however development and turnover of zooids occurs asynchronously and in a more independent manner. We generated a table of common stages of budding in Symplegma and Botryllus for comparative studies of asexual development. We tested dependent processes of budding among individuals of the colony by systemic bud or zooid removals. Although our results showed a higher degree of independence in bud development in S. brakenhielmi, we found a subtle colony-wide regulatory mechanism of modular development, i.e. new buds expedited development after the removal of all buds in the colony. Next, we characterized external morphology, ultrastructure, and abundance of circulatory blood cells in the vascular system of S. brakenhielmi. Macrophage-like cells (MLCs) are involved in zooid resorption and turnover. Proportions of MLCs in the blood of S. brakenhielmi corresponded to the peak of occurrence of this cell type during the budding cycle of B. schlosseri. We found several new blood cell types in S. brakenhielmi, including two cell types that resemble circulatory progenitor stem cells of other botryllid colonial ascidians. These cells showed features of undifferentiated cells and expressed mitotic marker Phospho-histone H3. Comparative studies of S. brakenhielmi and B. schlosseri

  11. Menaquinone and iron are essential for complex colony development in Bacillus subtilis.

    Directory of Open Access Journals (Sweden)

    Gidi Pelchovich

    Full Text Available Cells of undomesticated species of Bacillus subtilis frequently form complex colonies during spreading on agar surfaces. Given that menaquinone is involved in another form of coordinated behavior, namely, sporulation, we looked for a possible role for menaquinone in complex colony development (CCD in the B. subtilis strain NCIB 3610. Here we show that inhibition of menaquinone biosynthesis in B. subtilis indeed abolished its ability to develop complex colonies. Additionally some mutations of B. subtilis which confer defective CCD could be suppressed by menaquinone derivatives. Several such mutants mapped to the dhb operon encoding the genes responsible for the biosynthesis of the iron siderophore, bacillibactin. Our results demonstrate that both menaquinone and iron are essential for CCD in B. subtilis.

  12. Characterization of Rat Hair Follicle Stem Cells Selected by Vario Magnetic Activated Cell Sorting System

    International Nuclear Information System (INIS)

    Huang, Enyi; Lian, Xiaohua; Chen, Wei; Yang, Tian; Yang, Li

    2009-01-01

    Hair follicle stem cells (HfSCs) play crucial roles in hair follicle morphogenesis and hair cycling. These stem cells are self-renewable and have the multi-lineage potential to generate epidermis, sebaceous glands, and hair follicle. The separation and identification of hair follicle stem cells are important for further research in stem cell biology. In this study, we report on the successful enrichment of rat hair follicle stem cells through vario magnetic activated cell sorting (Vario MACS) and the biological characteristics of the stem cells. We chose the HfSCs positive surface markers CD34, α6-integrin and the negative marker CD71 to design four isolation strategies: positive selection with single marker of CD34, positive selection with single marker of α6-integrin, CD71 depletion followed by CD34 positive selection, and CD71 depletion followed by α6-integrin positive selection. The results of flow cytometry analysis showed that all four strategies had ideal effects. Specifically, we conducted a series of researches on HfSCs characterized by their high level of CD34, termed CD34 bri cells, and low to undetectable expression of CD34, termed CD34 dim cells. CD34 bri cells had greater proliferative potential and higher colony-forming ability than CD34 dim cells. Furthermore, CD34 bri cells had some typical characteristics as progenitor cells, such as large nucleus, obvious nucleolus, large nuclear:cytoplasmic ratio and few cytoplasmic organelles. Our findings clearly demonstrated that HfSCs with high purity and viability could be successfully enriched with Vario MACS

  13. The hypoxic microenvironment upgrades stem-like properties of ovarian cancer cells

    Directory of Open Access Journals (Sweden)

    Liang Dongming

    2012-05-01

    Full Text Available Abstract Background To study whether hypoxia influences the stem-like properties of ovarian cancer cells and their biological behavior under hypoxia. Method Ovarian cancer cell lines ES-2 and OVCAR-3 were cultivated in different oxygen tensions for proliferation, cell cycling and invasion analyses. The clonogenic potential of cells was examined by colony formation and sphere formation assays. Stem cell surface markers, SP and CD44bright and CD44dim cells were analyzed by flow cytometry. Protein expression of HIF-1α, HIF-2α, Ot3/4 and Sox2 were investigated by Western blotting. Results Both cell lines cultivated at hypoxic condition grew relatively slowly with extended G0/G1 phase. However, if the cells were pre-treated under 1% O2 for 48 hrs before brought back to normoxia, the cells showed significantly higher proliferation rate with higher infiltration capability, and significant more colonies and spheres, in comparison to the cells always cultivated under normoxia. CD44bright cells expressed significantly higher levels of Oct3/4 and Sox2 than the CD44dim cells and formed significantly more clones and spheres examined in vitro. Hypoxic treatment of the cells resulted in stronger CD44 expression in both cell lines, and stronger CD133 expression in the OVCAR-3 cell line. In parallel with these findings, significantly increased number of side population (SP cells and up-regulated expression of Oct3/4 and Sox2 in both ES-2 and OVCAR-3 cell lines were observed. Conclusion We conclude that ovarian cancer cells survive hypoxia by upgrading their stem-like properties through up-regulation of stemness-related factors and behave more aggressively when brought back to higher oxygen environment.

  14. After Nerve Injury, Lineage Tracing Shows That Myelin and Remak Schwann Cells Elongate Extensively and Branch to Form Repair Schwann Cells, Which Shorten Radically on Remyelination.

    Science.gov (United States)

    Gomez-Sanchez, Jose A; Pilch, Kjara S; van der Lans, Milou; Fazal, Shaline V; Benito, Cristina; Wagstaff, Laura J; Mirsky, Rhona; Jessen, Kristjan R

    2017-09-13

    There is consensus that, distal to peripheral nerve injury, myelin and Remak cells reorganize to form cellular columns, Bungner's bands, which are indispensable for regeneration. However, knowledge of the structure of these regeneration tracks has not advanced for decades and the structure of the cells that form them, denervated or repair Schwann cells, remains obscure. Furthermore, the origin of these cells from myelin and Remak cells and their ability to give rise to myelin cells after regeneration has not been demonstrated directly, although these conversions are believed to be central to nerve repair. Using genetic lineage-tracing and scanning-block face electron microscopy, we show that injury of sciatic nerves from mice of either sex triggers extensive and unexpected Schwann cell elongation and branching to form long, parallel processes. Repair cells are 2- to 3-fold longer than myelin and Remak cells and 7- to 10-fold longer than immature Schwann cells. Remarkably, when repair cells transit back to myelinating cells, they shorten ∼7-fold to generate the typically short internodes of regenerated nerves. The present experiments define novel morphological transitions in injured nerves and show that repair Schwann cells have a cell-type-specific structure that differentiates them from other cells in the Schwann cell lineage. They also provide the first direct evidence using genetic lineage tracing for two basic assumptions in Schwann cell biology: that myelin and Remak cells generate the elongated cells that build Bungner bands in injured nerves and that such cells can transform to myelin cells after regeneration. SIGNIFICANCE STATEMENT After injury to peripheral nerves, the myelin and Remak Schwann cells distal to the injury site reorganize and modify their properties to form cells that support the survival of injured neurons, promote axon growth, remove myelin-associated growth inhibitors, and guide regenerating axons to their targets. We show that the

  15. Generation of megakaryocytic progenitors from human embryonic stem cells in a feeder- and serum-free medium.

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    Marjorie Pick

    Full Text Available BACKGROUND: The production of human platelets from embryonic stem cells in a defined culture system is a prerequisite for the generation of platelets for therapeutic use. As an important step towards this goal, we report the differentiation of human embryonic stem cells (hESCs towards the megakaryocyte (Mk lineage using a 'spin embryoid body' method in serum-free differentiation medium. METHODOLOGY AND PRINCIPAL FINDINGS: Immunophenotypic analyses of differentiating hESC identified a subpopulation of cells expressing high levels of CD41a that expressed other markers associated with the Mk lineage, including CD110, CD42b and CD61. Differentiated cells were sorted on the basis of their expression of CD41a, CD34 and CD45 and assessed for Mk colony formation, expression of myeloid and Mk genes and ability to endoreplicate DNA. In a collagen-based colony assay, the CD41a⁺ cells sorted from these differentiation cultures produced 100-800 Mk progenitors at day 13 and 25-160 Mk progenitors at day 20 of differentiation per 100,000 cells assayed. Differentiated Mk cells produced platelet-like particles which expressed CD42b and were activated by ADP, similar to platelets generated from precursors in cord blood. These studies were complemented by real time PCR analyses showing that subsets of cells enriched for CD41a⁺ Mk precursors expressed high levels of Mk associated genes such as PF4 and MPL. Conversely, high levels of myeloid and erythroid related transcripts, such as GATA1, TAL1/SCL and PU.1, were detected in sorted fractions containing CD34⁺ and CD45⁺ cells. CONCLUSIONS: We describe a serum- and feeder-free culture system that enabled the generation of Mk progenitors from human embryonic stem cells. These cells formed colonies that included differentiated Mks that fragmented to form platelet-like particles. This protocol represents an important step towards the generation of human platelets for therapeutic use.

  16. Human disc cells in monolayer vs 3D culture: cell shape, division and matrix formation

    Directory of Open Access Journals (Sweden)

    Hanley Edward N

    2000-10-01

    Full Text Available Abstract Background The relationship between cell shape, proliferation, and extracellular matrix (ECM production, important aspects of cell behavior, is examined in a little-studied cell type, the human annulus cell from the intervertebral disc, during monolayer vs three-dimensional (3D culture. Results Three experimental studies showed that cells respond specifically to culture microenvironments by changes in cell shape, mitosis and ECM production: 1 Cell passages showed extensive immunohistochemical evidence of Type I and II collagens only in 3D culture. Chondroitin sulfate and keratan sulfate were abundant in both monolayer and 3D cultures. 2 Cells showed significantly greater proliferation in monolayer in the presence of platelet-derived growth factor compared to cells in 3D. 3 Cells on Matrigel™-coated monolayer substrates became rounded and formed nodular colonies, a finding absent during monolayer growth. Conclusions The cell's in vivo interactions with the ECM can regulate shape, gene expression and other cell functions. The shape of the annulus cell changes markedly during life: the young, healthy disc contains spindle shaped cells and abundant collagen. With aging and degeneration, many cells assume a strikingly different appearance, become rounded and are surrounded by unusual accumulations of ECM products. In vitro manipulation of disc cells provides an experimental window for testing how disc cells from given individuals respond when they are grown in environments which direct cells to have either spindle- or rounded-shapes. In vitro assessment of the response of such cells to platelet-derived growth factor and to Matrigel™ showed a continued influence of cell shape even in the presence of a growth factor stimulus. These findings contribute new information to the important issue of the influence of cell shape on cell behavior.

  17. Selective binding and oligomerization of the murine granulocyte colony-stimulating factor receptor by a low molecular weight, nonpeptidyl ligand.

    Science.gov (United States)

    Doyle, Michael L; Tian, Shin-Shay; Miller, Stephen G; Kessler, Linda; Baker, Audrey E; Brigham-Burke, Michael R; Dillon, Susan B; Duffy, Kevin J; Keenan, Richard M; Lehr, Ruth; Rosen, Jon; Schneeweis, Lumelle A; Trill, John; Young, Peter R; Luengo, Juan I; Lamb, Peter

    2003-03-14

    Granulocyte colony-stimulating factor regulates neutrophil production by binding to a specific receptor, the granulocyte colony-stimulating factor receptor, expressed on cells of the granulocytic lineage. Recombinant forms of granulocyte colony-stimulating factor are used clinically to treat neutropenias. As part of an effort to develop granulocyte colony-stimulating factor mimics with the potential for oral bioavailability, we previously identified a nonpeptidyl small molecule (SB-247464) that selectively activates murine granulocyte colony-stimulating factor signal transduction pathways and promotes neutrophil formation in vivo. To elucidate the mechanism of action of SB-247464, a series of cell-based and biochemical assays were performed. The activity of SB-247464 is strictly dependent on the presence of zinc ions. Titration microcalorimetry experiments using a soluble murine granulocyte colony-stimulating factor receptor construct show that SB-247464 binds to the extracellular domain of the receptor in a zinc ion-dependent manner. Analytical ultracentrifugation studies demonstrate that SB-247464 induces self-association of the N-terminal three-domain fragment in a manner that is consistent with dimerization. SB-247464 induces internalization of granulocyte colony-stimulating factor receptor on intact cells, consistent with a mechanism involving receptor oligomerization. These data show that small nonpeptidyl compounds are capable of selectively binding and inducing productive oligomerization of cytokine receptors.

  18. Comparison of Gingiva, Dental Pulp, and Periodontal Ligament Cells From the Standpoint of Mesenchymal Stem Cell Properties

    Science.gov (United States)

    Otabe, Koji; Muneta, Takeshi; Kawashima, Nobuyuki; Suda, Hideaki; Tsuji, Kunikazu; Sekiya, Ichiro

    2012-01-01

    The specific properties of mesenchymal stem cells (MSCs) in oral tissues still remain unknown though their existence has been previously reported. We collected gingiva, dental pulp, and periodontal ligament tissues from removed teeth and isolated MSCs. These MSCs were compared in terms of their yields per tooth, surface epitopes, and differentiation potentials by patient-matched analysis. For in vivo calcification analysis, rat gingival and dental pulp cells mounted on β-tricalcium phospateTCP were transplanted into the perivertebral muscle of rats for 6 weeks. Gingival cells and dental pulp cells showed higher yield per tooth than periodontal ligament cells (n=6, ppulp cells expressed MSC markers such as CD44, CD90, and CD166. Gingival and dental pulp cells obtained phenotypes of chondrocytes and adipocytes in vitro. Approximately 60% of the colonies of gingival cells and 40% of the colonies of dental pulp cells were positively stained with alizarin red in vitro, and both gingival and dental pulp cells were calcified in vivo. We clarified properties of MSCs derived from removed teeth. We could obtain a high yield of MSCs with osteogenic potential from gingiva and dental pulp. These results indicate that gingiva and dental pulp are putative cell sources for hard tissue regeneration. PMID:26858852

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

    International Nuclear Information System (INIS)

    Kato, Kengo; Kashiwakura, Ikuo; Kuwabara, Mikinori

    2011-01-01

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

  20. Reactivation of neutron killed mammalian cells by gamma irradiation: The observations, possible mechanism and implication

    International Nuclear Information System (INIS)

    Calkins, J.; Harrison, W.; Einspenner, M.

    1990-01-01

    We have observed that combinations of neutron plus gamma ray exposure can significantly increase the colony forming ability of monkey and human cell cultures over the neutron dose alone. The 'reactivation' of neutron killed mammalian cells by gamma rays is analogous to observations made in lower eukaryotic organisms and fits the pattern termed 'T repair' previously postulated for yeast and protozoans. (orig.)

  1. The role of donor characteristics and post-granulocyte colony-stimulating factor white blood cell counts in predicting the adverse events and yields of stem cell mobilization.

    Science.gov (United States)

    Chen, Shu-Huey; Yang, Shang-Hsien; Chu, Sung-Chao; Su, Yu-Chieh; Chang, Chu-Yu; Chiu, Ya-Wen; Kao, Ruey-Ho; Li, Dian-Kun; Yang, Kuo-Liang; Wang, Tso-Fu

    2011-05-01

    Granulocyte colony-stimulating factor (G-CSF) is now widely used for stem cell mobilization. We evaluated the role of post-G-CSF white blood cell (WBC) counts and donor factors in predicting adverse events and yields associated with mobilization. WBC counts were determined at baseline, after the third and the fifth dose of G-CSF in 476 healthy donors. Donors with WBC ≥ 50 × 10(3)/μL post the third dose of G-CSF experienced more fatigue, myalgia/arthralgia, and chills, but final post-G-CSF CD34(+) cell counts were similar. Although the final CD34(+) cell count was higher in donors with WBC ≥ 50 × 10(3)/μL post the fifth G-CSF, the incidence of side effects was similar. Females more frequently experienced headache, nausea/anorexia, vomiting, fever, and lower final CD34(+) cell count than did males. Donors with body mass index (BMI) ≥ 25 showed higher incidences of sweat and insomnia as well as higher final CD34(+) cell counts. Donor receiving G-CSF ≥ 10 μg/kg tended to experience bone pain, headache and chills more frequently. Multivariate analysis indicated that female gender is an independent factor predictive of the occurrence of most side effects, except for ECOG > 1 and chills. Higher BMI was also an independent predictor for fatigue, myalgia/arthralgia, and sweat. Higher G-CSF dose was associated with bone pain, while the WBC count post the third G-CSF was associated with fatigue only. In addition, one donor in the study period did not complete the mobilization due to suspected anaphylactoid reaction. Observation for 1 h after the first injection of G-CSF is required to prevent complications from unpredictable side effects.

  2. Effect of the p53 gene status on the sensitivity of oral squamous cell carcinoma cells to boron neutron capture therapy

    International Nuclear Information System (INIS)

    Fujita, Y.; Kamida, A.; Kato, I.; Yura, Y.; Ono, K.; Suzuki, M.; Sakurai, Y.; Ohnishi, T.; Ohnishi, K.

    2006-01-01

    The role of the p53 gene in the sensitivity of oral squamous cell carcinoma (SCC) to boron neutron capture therapy (BNCT) had not been studied. We examined the effect of boronophenylalanine (BPA)-mediated BNCT on oral SCC cells showing either wild-type p53 (SAS/neo) or mutated-type p53 (SAS/mp53). Survival ratio of cells was determined by colony formation. Cell viability was measured by MTT assay. Apoptotic cells were evaluated by flow cytometric analysis and nuclear DNA staining. When SAS/neo and SAS/mp53 cells were subjected to BNCT, more suppressive effects on colony formation and cell viability were observed in SAS/neo cells as compared with SAS/mp53. The proportion of apoptotic cells with DNA fragmentation was also increased in the cells with functional p53. These results suggest that oral SCC cells with mutated p53 cells are more resistant to BNCT than those with wild-type p53. BNCT must inhibit oral SCC cells in p53-dependent and p53-independent mechanisms. (author)

  3. Effect of human granulocyte macrophage-colony stimulating factor on differentiation and apoptosis of the human osteosarcoma cell line SaOS-2

    Directory of Open Access Journals (Sweden)

    L Postiglione

    2009-06-01

    Full Text Available We investigated the effects of human granulocyte macrophage- colony stimulating factor (GM-CSF on the relation between differentiation and apoptosis in SaOS-2 cells, an osteoblast-like cell line. To determine the relationship between these cellular processes, SaOS-2 cells were treated in vitro for 1, 7 and 14 days with 200 ng/mL GM-CSF and compared with untreated cells. Five nM insulin-like growth factor (IGF-I and 30 nM okadaic acid were used as negative and positive controls of apoptosis, respectively. Effects on cell differentiation were determined by ECM (extracellular matrix mineralization, morphology of some typical mature osteoblast differentiation markers, such as osteopontin and sialoprotein II (BSP-II, and production of bone ECM components such as collagen I. The results showed that treatment with GM-CSF caused cell differentiation accompanied by increased production of osteopontin and BSP-II, together with increased ECM deposition and mineralization. Flow cytometric analysis of annexin V and propidium iodide incorporation showed that GM-CSF up-regulated apoptotic cell death of SaOS-2 cells after 14 days of culture in contrast to okadaic acid, which stimulated SaOS-2 apoptosis only during the early period of culture. Endonucleolytic cleavage of genomic DNA, detected by “laddering analysis”, confirmed these data. The results suggest that GM-CSF induces osteoblastic differentiation and long-term apoptotic cell death of the SaOS-2 human osteosarcoma cell line, which in turn suggests a possible in vivo physiological role for GM-CSF on human osteoblast cells.

  4. Hematopoietic stem cell function in motheaten mice

    International Nuclear Information System (INIS)

    Shultz, L.D.; Bailey, C.L.; Coman, D.R.

    1983-01-01

    Mice homozygous for the autosomal recessive mutation ''motheaten'' have normal numbers of multipotential hematopoietic stem cells in the bone marrow and spleen as determined by spleen colony assay. Histologic examination shows no qualitative abnormality in morphology of stem cell colonies in recipients of bone marrow or spleen cells from motheaten mice. Despite the apparently normal ontogeny, distribution, and differentiative capacity of CFU stem cells, bone marrow and spleen cells from motheaten mice fail to save congenic +/+ lethally gamma-irradiated hosts. This impaired lifesparing capacity is not due to defective self-renewal but appears to be due in part to pulmonary hemorrhage from alveolar capillaries in the gamma-irradiated hosts. Treatment of motheaten mice with 500 R gamma-irradiation followed by reconstitution with normal bone marrow cells increases the lifespan of this mutant to 10 months of age. The early onset of pneumonitis and subsequent short lifespan of motheaten mice is determined at the level of progenitor cells in the bone marrow

  5. Dysregulation of endothelial colony-forming cell function by a negative feedback loop of circulating miR-146a and -146b in cardiovascular disease patients.

    Directory of Open Access Journals (Sweden)

    Ting-Yu Chang

    Full Text Available Functional impairment of endothelial colony-forming cells (ECFCs, a specific cell lineage of endothelial progenitor cells (EPCs is highly associated with the severity of coronary artery disease (CAD, the most common type of cardiovascular disease (CVD. Emerging evidence show that circulating microRNAs (miRNAs in CAD patients' body fluid hold a great potential as biomarkers. However, our knowledge of the role of circulating miRNA in regulating the function of ECFCs and the progression of CAD is still in its infancy. We showed that when ECFCs from healthy volunteers were incubated with conditioned medium or purified exosomes of cultured CAD ECFCs, the secretory factors from CAD ECFCs dysregulated migration and tube formation ability of healthy ECFCs. It is known that exosomes influence the physiology of recipient cells by introducing RNAs including miRNAs. By using small RNA sequencing (smRNA-seq, we deciphered the circulating miRNome in the plasma of healthy individual and CAD patients, and found that the plasma miRNA spectrum from CAD patients was significantly different from that of healthy control. Interestingly, smRNA-seq of both healthy and CAD ECFCs showed that twelve miRNAs that had a higher expression in the plasma of CAD patients also showed higher expression in CAD ECFCs when compared with healthy control. This result suggests that these miRNAs may be involved in the regulation of ECFC functions. For identification of potential mRNA targets of the differentially expressed miRNA in CAD patients, cDNA microarray analysis was performed to identify the angiogenesis-related genes that were down-regulated in CAD ECFCs and Pearson's correlation were used to identify miRNAs that were negatively correlated with the identified angiogenesis-related genes. RT-qPCR analysis of the five miRNAs that negatively correlated with the down-regulated angiogenesis-related genes in plasma and ECFC of CAD patients showed miR-146a-5p and miR-146b-5p up

  6. Role of Mesenchymal-Derived Stem Cells in Stimulating Dormant Tumor Cells to Proliferate and Form Clinical Metastases

    Science.gov (United States)

    2017-07-01

    Clinical Metastases PRINCIPAL INVESTIGATOR: Rosandra Kaplan CONTRACTING ORGANIZATION: The Geneva Foundation Tacoma, WA 98402 REPORT DATE: July 2017...2017 4. TITLE AND SUBTITLE Role of Mesenchymal-Derived Stem Cells in Stimulating Dormant Tumor Cells to Proliferate and Form Clinical Metastases 5a...PRODUCTS:  publications, conference papers, and presentations ; Jennifer Zhu submitted an abstract and will present this work at the Annual

  7. Human papillomavirus 16 E5 induces bi-nucleated cell formation by cell-cell fusion

    International Nuclear Information System (INIS)

    Hu Lulin; Plafker, Kendra; Vorozhko, Valeriya; Zuna, Rosemary E.; Hanigan, Marie H.; Gorbsky, Gary J.; Plafker, Scott M.; Angeletti, Peter C.; Ceresa, Brian P.

    2009-01-01

    Human papillomaviruses (HPV) 16 is a DNA virus encoding three oncogenes - E5, E6, and E7. The E6 and E7 proteins have well-established roles as inhibitors of tumor suppression, but the contribution of E5 to malignant transformation is controversial. Using spontaneously immortalized human keratinocytes (HaCaT cells), we demonstrate that expression of HPV16 E5 is necessary and sufficient for the formation of bi-nucleated cells, a common characteristic of precancerous cervical lesions. Expression of E5 from non-carcinogenic HPV6b does not produce bi-nucleate cells. Video microscopy and biochemical analyses reveal that bi-nucleates arise through cell-cell fusion. Although most E5-induced bi-nucleates fail to propagate, co-expression of HPV16 E6/E7 enhances the proliferation of these cells. Expression of HPV16 E6/E7 also increases bi-nucleated cell colony formation. These findings identify a new role for HPV16 E5 and support a model in which complementary roles of the HPV16 oncogenes lead to the induction of carcinogenesis

  8. [Macrophage colony stimulating factor enhances non-small cell lung cancer invasion and metastasis by promoting macrophage M2 polarization].

    Science.gov (United States)

    Li, Y J; Yang, L; Wang, L P; Zhang, Y

    2017-06-23

    Objective: To investigate the key cytokine which polarizes M2 macrophages and promotes invasion and metastasis in non-small cell lung cancer (NSCLC). Methods: After co-culture with A549 cells in vitro, the proportion of CD14(+) CD163(+) M2 macrophages in monocytes and macrophage colony stimulating factor (M-CSF) levels in culture supernatant were detected by flow cytometry, ELISA assay and real-time qPCR, respectively. The effects of CD14(+) CD163(+) M2 macrophages on invasion of A549 cells and angiogenesis of HUVEC cells were measured by transwell assay and tubule formation assay, respectively. The clinical and prognostic significance of M-CSF expression in NSCLC was further analyzed. Results: The percentage of CD14(+) CD163(+) M2 macrophages in monocytes and the concentration of M-CSF in the supernatant followed by co-culture was (12.03±0.46)% and (299.80±73.76)pg/ml, respectively, which were significantly higher than those in control group [(2.80±1.04)% and (43.07±11.22)pg/ml, respectively, P macrophages in vitro . M2 macrophages enhanced the invasion of A549 cells (66 cells/field vs. 26 cells/field) and the angiogenesis of HUVEC cells (22 tubes/field vs. 8 tubes/field). The mRNA expression of M-CSF in stage Ⅰ-Ⅱ patients (16.23±4.83) was significantly lower than that in stage Ⅲ-Ⅳ (53.84±16.08; P macrophages, which can further promote the metastasis and angiogenesis of NSCLC. M-CSF could be used as a potential therapeutic target of NSCLC.

  9. The effect of low static magnetic field on osteogenic and adipogenic differentiation potential of human adipose stromal/stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Marędziak, Monika, E-mail: monika.maredziak@gmail.com [Faculty of Veterinary Medicine, University of Environmental and Life Sciences, Wrocław (Poland); Wroclaw Research Centre EIT+, Wrocław (Poland); Śmieszek, Agnieszka, E-mail: smieszek.agnieszka@gmail.com [Wroclaw Research Centre EIT+, Wrocław (Poland); Faculty of Biology, University of Environmental and Life Sciences, Wrocław (Poland); Tomaszewski, Krzysztof A., E-mail: krtomaszewski@gmail.com [Department of Anatomy, Jagiellonian University Medical College, Krakow (Poland); Lewandowski, Daniel, E-mail: daniel.lewandowski@pwr.wroc.pl [Institute of Materials Science and Applied Mechanics, Wroclaw University of Technology, Wroclaw (Poland); Marycz, Krzysztof, E-mail: krzysztofmarycz@interia.pl [Wroclaw Research Centre EIT+, Wrocław (Poland); Faculty of Biology, University of Environmental and Life Sciences, Wrocław (Poland)

    2016-01-15

    The aim of this work was to investigate the effects of static magnetic field (SMF) on the osteogenic properties of human adipose derived mesenchymal stem cells (hASCs). In this study in seven days viability assay we examined the impact of SMF on cells proliferation rate, population doubling time, and ability to form single-cell derived colonies. We have also examined cells' morphology, ultrastructure and osteogenic properties on the protein as well as mRNA level. We established a complex approach, which enabled us to obtain information about SMF and hASCs potential in the context of differentiation into osteogenic and adipogenic lineages. We demonstrated that SMF enhances both viability and osteogenic properties of hASCs through higher proliferation factor and shorter population doubling time. We have also observed asymmetrically positioned nuclei and organelles after SMF exposition. With regards to osteogenic properties we observed increased levels of osteogenic markers i.e. osteopontin, osteocalcin and increased ability to form osteonodules with positive reaction to Alizarin Red dye. We have also shown that SMF besides enhancing osteogenic properties of hASCs, simultaneously decreases their ability to differentiate into adipogenic lineage. Our results clearly show a direct influence of SMF on the osteogenic potential of hASCs. These results provide key insights into the role of SMF on their cellular fate and properties. - Graphical abstract: Influence of static magnetic field on viability and differentiation properties of human adipose derived mesenchymal stem cells. Abbreviations: SMF – static magnetic field; hASCs – human adipose derived mesenchymal stem cells; PF – proliferation factor; PDT – population doubling time; CFU-E –> colony forming unit efficiency; OPN – osteopontin; OCL – osteocalcin; Col – collagen type I; BMP-2 – bone morphogenetic protein 2; Ca – calcium; P – phosphorus. - Highlights: • Effects of static

  10. The effect of low static magnetic field on osteogenic and adipogenic differentiation potential of human adipose stromal/stem cells

    International Nuclear Information System (INIS)

    Marędziak, Monika; Śmieszek, Agnieszka; Tomaszewski, Krzysztof A.; Lewandowski, Daniel; Marycz, Krzysztof

    2016-01-01

    The aim of this work was to investigate the effects of static magnetic field (SMF) on the osteogenic properties of human adipose derived mesenchymal stem cells (hASCs). In this study in seven days viability assay we examined the impact of SMF on cells proliferation rate, population doubling time, and ability to form single-cell derived colonies. We have also examined cells' morphology, ultrastructure and osteogenic properties on the protein as well as mRNA level. We established a complex approach, which enabled us to obtain information about SMF and hASCs potential in the context of differentiation into osteogenic and adipogenic lineages. We demonstrated that SMF enhances both viability and osteogenic properties of hASCs through higher proliferation factor and shorter population doubling time. We have also observed asymmetrically positioned nuclei and organelles after SMF exposition. With regards to osteogenic properties we observed increased levels of osteogenic markers i.e. osteopontin, osteocalcin and increased ability to form osteonodules with positive reaction to Alizarin Red dye. We have also shown that SMF besides enhancing osteogenic properties of hASCs, simultaneously decreases their ability to differentiate into adipogenic lineage. Our results clearly show a direct influence of SMF on the osteogenic potential of hASCs. These results provide key insights into the role of SMF on their cellular fate and properties. - Graphical abstract: Influence of static magnetic field on viability and differentiation properties of human adipose derived mesenchymal stem cells. Abbreviations: SMF – static magnetic field; hASCs – human adipose derived mesenchymal stem cells; PF – proliferation factor; PDT – population doubling time; CFU-E –> colony forming unit efficiency; OPN – osteopontin; OCL – osteocalcin; Col – collagen type I; BMP-2 – bone morphogenetic protein 2; Ca – calcium; P – phosphorus. - Highlights: • Effects of static

  11. Identification of Cell Type-Specific Differences in Erythropoietin Receptor Signaling in Primary Erythroid and Lung Cancer Cells.

    Directory of Open Access Journals (Sweden)

    Ruth Merkle

    2016-08-01

    Full Text Available Lung cancer, with its most prevalent form non-small-cell lung carcinoma (NSCLC, is one of the leading causes of cancer-related deaths worldwide, and is commonly treated with chemotherapeutic drugs such as cisplatin. Lung cancer patients frequently suffer from chemotherapy-induced anemia, which can be treated with erythropoietin (EPO. However, studies have indicated that EPO not only promotes erythropoiesis in hematopoietic cells, but may also enhance survival of NSCLC cells. Here, we verified that the NSCLC cell line H838 expresses functional erythropoietin receptors (EPOR and that treatment with EPO reduces cisplatin-induced apoptosis. To pinpoint differences in EPO-induced survival signaling in erythroid progenitor cells (CFU-E, colony forming unit-erythroid and H838 cells, we combined mathematical modeling with a method for feature selection, the L1 regularization. Utilizing an example model and simulated data, we demonstrated that this approach enables the accurate identification and quantification of cell type-specific parameters. We applied our strategy to quantitative time-resolved data of EPO-induced JAK/STAT signaling generated by quantitative immunoblotting, mass spectrometry and quantitative real-time PCR (qRT-PCR in CFU-E and H838 cells as well as H838 cells overexpressing human EPOR (H838-HA-hEPOR. The established parsimonious mathematical model was able to simultaneously describe the data sets of CFU-E, H838 and H838-HA-hEPOR cells. Seven cell type-specific parameters were identified that included for example parameters for nuclear translocation of STAT5 and target gene induction. Cell type-specific differences in target gene induction were experimentally validated by qRT-PCR experiments. The systematic identification of pathway differences and sensitivities of EPOR signaling in CFU-E and H838 cells revealed potential targets for intervention to selectively inhibit EPO-induced signaling in the tumor cells but leave the responses in

  12. Combined effects of nitrogen content in media and Ochromonas sp. grazing on colony formation of cultured Microcystis aeruginosa

    Directory of Open Access Journals (Sweden)

    Zhou YANG

    2010-08-01

    Full Text Available To gain insight into the combined effects of nitrogen content in media and flagellate grazing on colony formation of Microcystis aeruginosa, we added Ochromonas sp. to M. aeruginosa cultured in different nitrogen content media for 7 days. Results showed that M. aeruginosa could be efficiently ingested by Ochromonas sp., no matter what nitrogen content media M. aeruginosa was cultured in. Colony formation was observed in M. aeruginosa in all Ochromonas sp. grazing treatments during the experiment. In contrast, M. aeruginosa populations in the controls were strongly dominated by unicellular and paired cell forms, and no colonies were observed. Among all Ochromonas sp. grazing treatments, the mean numbers of cells per particle of M. aeruginosa increased with decreased nitrogen concentration (except 0% N, therefore colony formation of M. aeruginosa can be enhanced under lower nitrogen conditions. This suggests that both nitrogen content and Ochromonas sp. grazing combine to affect M. aeruginosa colony formation. Three-way ANOVA showed a statistically significant interaction between time (day 1, 3, 5, and 7, treatment (with and without Ochromonas sp. grazing and N content (0%, 10%, 25%, and 100% N on the mean numbers of cells per particle, i.e. the extent of colony formation. At the end of the experiment, the influence of nitrogen content (except 0% N on the numbers of cells per particle followed a rectangular hyperbolic response. The experiments demonstrated that there exists a combined effect of nitrogen concentration and flagellate grazing on colony formation of M. aeruginosa under laboratory conditions.

  13. Characterization in vitro and in vivo of progressively adriamycin-resistant B16-BL6 mouse melanoma cells.

    Science.gov (United States)

    Ganapathi, R; Grabowski, D; Schmidt, H; Bell, D; Melia, M

    1987-07-01

    Adriamycin (ADR)-resistant sublines of B16-BL6 mouse melanoma selected by exposure to increasing concentrations of ADR were characterized in vitro for growth properties and in vivo for tumorigenicity and pulmonary metastases. The progressively resistant sublines adapted to grow in the presence of 0.025, 0.05, 0.1, and 0.25 microgram/ml ADR in monolayer culture were found to be 5-, 10-, 20-, and 40-fold ADR-resistant, respectively, compared to the parental sensitive cells, using a soft-agar colony assay and continuous ADR treatment for 7 days. The doubling time in monolayer culture of the parent sensitive and progressively ADR-resistant sublines of B16-BL6 melanoma cells was approximately 16-18 h. Although the colony-forming efficiency in soft agar of parental sensitive cells was only 0.5-4%, the 5-, 10-, 20-, and 40-fold ADR-resistant sublines had colony-forming efficiencies of 15, 20, 30, and 77%, respectively. Tumorigenicity in C57BL/6 mice of progressively ADR-resistant sublines was similar to parental sensitive cells following s.c. and i.p. implantation of 10(5)-10(6) tumor cells. Experimental pulmonary metastases were significantly lower in ADR-resistant sublines with progressive resistance. Additionally, unlike the parental sensitive and 5-fold ADR-resistant B16-BL6 cells, the 10-, 20-, and 40-fold ADR-resistant sublines were spontaneously nonmetastatic. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunochemical detection of P-glycoprotein revealed the presence of a Mr 170,000 plasma membrane glycoprotein in the 40-fold ADR-resistant subline and its counterpart maintained for 1 year in ADR-free medium. Results from this study suggest that progressively ADR-resistant B16-BL6 mouse melanoma cells selected in vitro demonstrate a marked increase in colony formation in soft agar and a decrease in the ability to produce pulmonary metastases, without alterations in tumorigenicity.

  14. HBx induced AFP receptor expressed to activate PI3K/AKT signal to promote expression of Src in liver cells and hepatoma cells

    International Nuclear Information System (INIS)

    Zhu, Mingyue; Guo, Junli; Li, Wei; Xia, Hua; Lu, Yan; Dong, Xu; Chen, Yi; Xie, Xieju; Fu, Shigan; Li, Mengsen

    2015-01-01

    Hepatitis B virus (HBV)-X protein(HBx) is a transactivator of host several cellular genes including alpha-fetoprotein(AFP) and AFP receptor(AFPR) which contributes to HBV-associated tumor development. The expression of AFP/AFPR are correlated with hepatocellular carcinoma(HCC)-initial cells. But the role of AFP and AFPR in promoting occurrence of HBV-related HCC were still unclear. A total of 71 clinical patients’ liver specimens, normal human liver cells L-02 and HCC cell lines, PLC/PRF/5 were selected for analyzing the effects of HBx on expression of AFP, AFPR and Src. The expression of goal proteins were detected by Immunohistochemical stained and Western blotting; HBx-expressed vectors were constructed and transfected into L-02 cells, laser confocal microscopy was applied to observe expression and location of AFP, AFPR and Src in the normal liver cells and HCC cells, soft agar colony formation assay was used to observe colonies formed of the cells. We confirmed HBx gives preference to promote the expression of AFP and AFPR; HBx priors to up-regulate the expression of AFPR and AFP in L-02 cells and in normal liver specimens; AFPR signal been able to stimulate Src expression. The results also indicated that phosphatidylinositol 3-kinase(PI3K) inhibitors Ly294002 and GDC0941 effectively suppress AFPR mediated up-regulation expression of Src in AFPR positive HCC lines. HBx priors to drive the expression of AFP and AFPR to promote expression of Src in normal liver cells and hepatoma cells; AFP and AFPR maybe play pivotal role in HBV-related hepatocarcinogenesis; Targeting AFPR is an available therapeutic strategy of HCC. The online version of this article (doi:10.1186/s12885-015-1384-9) contains supplementary material, which is available to authorized users

  15. Avidin-biotin-based approach to forming heterotypic cell clusters and cell sheets on a gas-permeable membrane

    Energy Technology Data Exchange (ETDEWEB)

    Hamon, M; Ozawa, T; Montagne, K; Kojima, N; Ishii, R; Sakai, Y [Institute of Industrial Science (IIS), University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505 (Japan); Yamaguchi, S; Nagamune, T [Department of Bioengineering, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Ushida, T, E-mail: mzh0026@auburn.edu [Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan)

    2011-09-15

    Implantation of sheet-like liver tissues is a promising method in hepatocyte-based therapies, because angiogenesis is expected to occur upon implantation from the surrounding tissues. In this context, we introduce here a new methodology for the formation of a functional thick hepatic tissue usable for cell sheet technology. First, we report the formation of composite tissue elements in suspension culture. Composite elements were composed of human hepatoma Hep G2 cells and mouse NIH/3T3 fibroblasts which are important modulators for thick-tissue formation. To overcome the very low attachment and organization capability between different cells in suspension, we synthesized a new cell-to-cell binding molecule based on the avidin-biotin binding system that we previously applied to attach hepatocytes on artificial substrata. This newly synthesized biotin-conjugated biocompatible anchoring molecule was inserted in the plasma membrane of both cell types. NIH/3T3 cells were further conjugated with avidin and incubated with biotin-presenting Hep G2 cells to form highly composite tissue elements. Then, we seeded those elements on highly gas-permeable membranes at their closest packing density to induce the formation of a thick, composite, functional hepatic tissue without any perfusion. This methodology could open a new way to engineer implantable thick liver tissue sheets where different cell types are spatially organized and well supplied with oxygen.

  16. Induced Retro-Differentiation of Human Retinal Pigment Epithelial Cells on PolyHEMA.

    Science.gov (United States)

    Nazemroaya, Fatemeh; Soheili, Zahra-Soheila; Samiei, Shahram; Deezagi, Abdolkhalegh; Ahmadieh, Hamid; Davari, Malihe; Heidari, Razeih; Bagheri, Abouzar; Darvishalipour-Astaneh, Shamila

    2017-10-01

    Retinal pigment epithelium (RPE) cells represent a great potential to rescue degenerated cells of the damaged retina. Activation of the virtually plastic properties of RPE cells may aid in recovery of retinal degenerative disorders without the need for entire RPE sheet transplantation. Poly (2-hydroxyethyl methacrylate)(PolyHEMA) is one of the most important hydrogels in the biomaterials world. This hydrophobic polymer does not normally support attachment of mammalian cells. In the current study we investigated the effect of PolyHEMA as a cell culture substrate on the growth, differentiation, and plasticity of hRPE cells. hRPE cells were isolated from neonatal human globes and cultured on PolyHEMA and polystyrene substrates (as controls) in 24-well culture plates. DMEM/F12 was supplemented with 10% fetal bovine serum (FBS) and/or 30% human amniotic fluid (HAF) for cultured cells on polystyrene and PolyHEMA coated vessels. Morphology, rate of cell proliferation and cell death, MTT assay, immunocytochemistry and Real-Time RT-PCR were performed to investigate the effects of PolyHEMA on the growth and differentiation of cultured hRPE cells. Proliferation rate of the cells that had been cultured on PolyHEMA was reduced; PolyHEMA did not induce cell death in the hRPE cultures. hRPE cells cultured on PolyHEMA formed many giant spheroid colonies. The giant colonies were re-cultured and the presence of retinal progenitor markers and markers of hRPE cells were detected in cell cultures on PolyHEMA. PolyHEMA seems to be promising for both maintenance and de-differentiation of hRPE cells and expansion of the retinal progenitor cells from the cultures that are originated from hRPE cells. J. Cell. Biochem. 118: 3080-3089, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  17. Granulocyte Colony-stimulating Factor-primed Bone Marrow: An Excellent Stem-cell Source for Transplantation in Acute Myelocytic Leukemia and Chronic Myelocytic Leukemia

    Directory of Open Access Journals (Sweden)

    Yuhang Li

    2015-01-01

    Full Text Available Background: Steady-state bone marrow (SS-BM and granulocyte colony-stimulating growth factor-primed BM/peripheral blood stem-cell (G-BM/G-PBSC are the main stem-cell sources used in allogeneic hematopoietic stem-cell transplantation. Here, we evaluated the treatment effects of SS-BM and G-BM/G-PBSC in human leucocyte antigen (HLA-identical sibling transplantation. Methods: A total of 226 patients (acute myelogenous leukemia-complete remission 1, chronic myelogenous leukemia-chronic phase 1 received SS-BM, G-BM, or G-PBSC from an HLA-identical sibling. Clinical outcomes (graft-versus-host disease [GVHD], overall survival, transplant-related mortality [TRM], and leukemia-free survival [LFS] were analyzed. Results: When compared to SS-BM, G-BM gave faster recovery time to neutrophil or platelet (P 0.05. Conclusions: G-CSF-primed bone marrow shared the advantages of G-PBSC and SS-BM. We conclude that G-BM is an excellent stem-cell source that may be preferable to G-PBSC or SS-BM in patients receiving HLA-identical sibling hematopoietic stem-cell transplantation.

  18. Behavior of a Spontaneously Arising Human Retinal Pigment Epithelial Cell Line Cultivated on Thin Alginate Film.

    Science.gov (United States)

    Najafabadi, Hoda Shams; Soheili, Zahra-Soheila; Ganji, Shahla Mohammad

    2015-01-01

    A cell line spontaneously derived from human retinal pigment epithelium (hRPE) was cultured on alginate film gelatinized with different concentrations of neurobasal cell culture medium (NCCM) to assess its growth and morphological behavior on this naturally occurring polysaccharide. Neonatal human globes were used to isolate hRPE cells. They were cultured in Dulbecco's modified Eagle's-medium-and-Ham's-F12-medium-(DMEM/F12) supplemented with 10% fetal bovine serum (FBS). Cultures were continuously studied using phase contrast microscopy. After the nineth passage, cells were characterized through immunocytochemical analysis for Oct4, Chx10, and Pax6 and Ki67 markers. In each well of a 6-well microplate, 1 and 2% weight/volume (w/v) alginate in deionized water was added and gelatinized using 1× and 10× NCCM. hRPE cells were cultured at a density of 2 × 105 cells/well in alginate-coated microplates. After 5 days, hRPE colonies were harvested and re-plated on polystyrene substrates. Morphology and growth of hRPE cultures were determined during the next 2 weeks. The first few passages of the cultures were purely hRPE cells that revealed typical morphological features of the pigmented epithelium. They made spaces, devoid of cells, between hRPE cell monolayer and fill in the unoccupied spaces. They grew faster than native RPE cells and rapidly overgrew. Immunocytochemical test revealed that the founded cells expressed Chx10, Pax6, Ki67 and Oct4. The hRPE cells survived unlimitedly on alginate film and formed giant adjoining colonies. After re-plating, hRPE colonies adhered quickly on polystyrene and displayed native hRPE morphological features. Alginate film can support the survival and growth of hRPE cells and induce the cells to re-organize in tissue-like structures.

  19. Phytohemagglutinin (PHA) stimulation of peripheral-blood lymphocytes and stem cell take

    Energy Technology Data Exchange (ETDEWEB)

    Astaldi, G [Blood Research Foundation Center, Tortona, Italy; Karanovic, D; Vettori, P P; Karanovic, J; Piletic, O

    1974-01-01

    The effect of PHA-stimulation of peripheral-blood lymphocytes on the spleen-colony formation in irradiated rats was examined. 25-day old Wistar rats underwent total-body irradiation (600 R), and they were used as recipients. On the other hand, 2 and /sup 1///sub 2/ month old untreated Wistar rats were used as donors of peripheral-blood lymphocytes, which were obtained by sedimentation with Dextraven from defibrinated blood. Four rat lots were used. The 1st one did not receive irradiation, and was kept as ''blank control.'' The 2nd one was just irradiated and kept as ''radiated control.'' The 3rd and the 4th rat lots of the series were irradiated, but the former lot was injected i.v. with 5 x 10/sup 7/ peripheral-blood untreated lymphocytes, whereas the fourth lot was injected i.v. with the same amount of lymphocytes, which were previously incubated in vitro for 24 hrs with PHA-M (Difco). The results showed that the PHA-incubation of transplanted peripheral-blood lymphocytes significantly increases the number and size of the macroscopic spleen colonies, in relationship to the colonies which occurs after transplantation of untreated lymphocytes. Histo-cytological observation clearly showed that the colonies formed after injection of mitogen-pretreated peripheral-blood lymphocytes were predominantly of erythroid type and, then, of non-differentiated cells. Only a few of them were of a mixed type, consisting of both undifferentiated cells and erythroid cells.

  20. [Biological characteristics of mesenchymal stem cell and hematopoietic stem cell in the co-culture system].

    Science.gov (United States)

    Wei, Wei; Xu, Chao; Ye, Zhi-Yong; Huang, Xiao-Jun; Yuan, Jia-En; Ma, Tian-Bao; Lin, Han-Biao; Chen, Xiu-Qiong

    2016-10-25

    The aim of the present study was to obtain the qualified hematopoietic stem/progenitor cells (HSC/HPC) and human umbilical cord-mesenchymal stem cells (MSC) in vitro in the co-culture system. Cord blood mononuclear cells were separated from umbilical cord blood by Ficoll lymphocyte separation medium, and then CD34 + HSC was collected by MACS immunomagnetic beads. The selected CD34 + HSC/HPC and MSC were transferred into culture flask. IMDM culture medium with 15% AB-type cord plasma supplemented with interleukin-3 (IL-3), IL-6, thrombopoietin (TPO), stem cell factor (SCF) and FMS-like tyrosine kinase 3 ligand (Flt-3L) factors were used as the co-culture system for the amplification of HSC/HPC and MSC. The cellular growth status and proliferation on day 6 and 10 after co-culture were observed by using inverted microscope. The percentage of positive expression of CD34 in HSC/HPC, as well as the percentages of positive expressions of CD105, CD90, CD73, CD45, CD34 and HLA-DR in the 4 th generation MSC, was tested by flow cytometry. Semisolid colony culture was used to test the HSC/HPC colony forming ability. The osteogenic, chondrogenesis and adipogenic ability of the 4 th generation MSC were assessed. The karyotype analysis of MSC was conducted by colchicines. The results demonstrated that the HSC/HPC of co-culture group showed higher ability of amplification, CFU-GM and higher CD34 + percentage compared with the control group. The co-cultured MSC maintained the ability to differentiate into bone cells, fat cells and chondrocytes. And the karyotype stability of MSC remained normal. These results reveal that the appropriate co-culture system for MSC and HSC is developed, and via this co-culture system we could gain both two kinds of these cells. The MSCs under the co-culture system maintain the biological characteristics. The CFU-GM ability, cell counting and the flow cytometry results of HSC/HPC under the co-culture system are conform to the criterion, showing that

  1. Role of Mesenchymal Derived Stem Cells in Stimulating Dormant Tumor Cells to Proliferate and Form Clinical Metastases

    Science.gov (United States)

    2017-07-01

    Clinical Metastases PRINCIPAL INVESTIGATOR: Jeffrey Green CONTRACTING ORGANIZATION: The Geneva Foundation Tacoma, WA 98402 REPORT DATE: July 2017 TYPE...2016 - 14 June 2017 4. TITLE AND SUBTITLE Role of Mesenchymal-Derived Stem Cells in Stimulating Dormant Tumor Cells to Proliferate and Form Clinical ...and/or select agents. Nothing to report. 6. PRODUCTS: • publications, conference papers, and presentations ; Jennifer Zhu submitted an abstract and will

  2. Volumetric Analysis of 3-D-Cultured Colonies in Wet Alginate Spots Using 384-Pillar Plate.

    Science.gov (United States)

    Lee, Dong Woo; Choi, Yea-Jun; Lee, Sang-Yun; Kim, Myoung-Hee; Doh, Il; Ryu, Gyu Ha; Choi, Soo-Mi

    2018-06-01

    The volumetric analysis of three-dimensional (3-D)-cultured colonies in alginate spots has been proposed to increase drug efficacy. In a previously developed pillar/well chip platform, colonies within spots are usually stained and dried for analysis of cell viability using two-dimensional (2-D) fluorescent images. Since the number of viable cells in colonies is directly related to colony volume, we proposed the 3-D analysis of colonies for high-accuracy cell viability calculation. The spots were immersed in buffer, and the 3-D volume of each colony was calculated from the 2-D stacking fluorescent images of the spot with different focal positions. In the experiments with human gastric carcinoma cells and anticancer drugs, we compared cell viability values calculated using the 2-D area and 3-D volume of colonies in the wet and dried alginate spots, respectively. The IC 50 value calculated using the 3-D volume of the colonies (9.5 μM) was less than that calculated in the 2-D area analysis (121.5 μM). We observed that the colony showed a more sensitive drug response regarding volume calculated from the 3-D image reconstructed using several confocal images than regarding colony area calculated in the 2-D analysis.

  3. Effects of cell concentrations on the survival and repopulation of haemopoietic stem cells in irradiated bone marrow cell culture in vitro

    International Nuclear Information System (INIS)

    Fujitake, Hideki; Okamoto, Yuruko; Okubo, Hiroshi; Miyanomae, Takeshi; Kumagai, Keiko; Mori, K.J.

    1981-01-01

    Effects of cell concentrations on the survival and repopulation of haemopoietic stem cells after irradiation were studied in the long-term culture of mouse bone marrow cells in vitro. No difference was observed in the survival of the stem cells among cultures in which 0 - 10 7 cells were re-inoculated on the adherent cell colonies in the culture flask. Stem cells showed a significant proliferation within 1 week and the number of the stem cells exceeded the control in 3 weeks after irradiation in the cultures with less than 10 6 re-inoculated cells per flask. In contrast, there was a considerable delay in the onset of stem cell proliferation after irradiation in the culture with 10 7 cells per flask. Based on these results, a possibility that a stimulator of stem cell proliferation, released from irradiated stromal cells, is cancelled by an inhibitory factor produced by irradiated or unirradiated haemopoietic cells is postulated. (author)

  4. The effects of (-)-epigallocatechin-3-gallate on the proliferation and differentiation of human megakaryocytic progenitor cells

    International Nuclear Information System (INIS)

    Monzen, Satoru; Takahashi, Kenji; Abe, Yoshinao; Kashiwakura, Ikuo; Mori, Takao; Inanami, Osamu; Kuwabara, Mikinori

    2006-01-01

    Epigallocatechin-3-gallate (EGCg) has been widely recognized as a powerful antioxidant and free radical scavenger. The effects of EGCg on the proliferation and differentiation of X-irradiated megakaryocytic progenitor cells (colony-forming unit-megakaryocyte, CFU-Meg) using CD34 + cells prepared from human placental and umbilical cord blood have been shown. In the absence of exogenous thrombopoietin (TPO), no colonies are observed in cultures containing or lacking EGCg (1 nM-100 μM). In the presence of TPO, in contrast, EGCg significantly promotes CFU-Meg-derived colony formations within the 10-100 nM range. A 1.5-fold increase in the total number of CFU-Meg has been counted compared with the control. These favorable effects of EGCg are also observed in the culture of CD34 + cells before and after X irradiation with 2 Gy. Moreover, in order to investigate the function of EGCg promoting megakaryocyto-poiesis and thrombopoiesis in ex vivo cultures, both non-irradiated and X-irradiated CD34 + cells are grown in liquid cultures supplemented with TPO. In both cultures, EGCg increases the total number of cells and megakaryocytes. It has been suggested that the favorable effects of EGCg reduce the risk factor from radiation damage in megakaryocytopoiesis. (author)

  5. Multidrug resistance and retroviral transduction potential in human small cell lung cancer cell lines

    DEFF Research Database (Denmark)

    Theilade, M D; Gram, G J; Jensen, P B

    1999-01-01

    of blue colonies after X-Gal staining of the cells grown in soft agar. All examined SCLC cell lines were transducible with either vector. Transduction efficiencies varied from 5.7% to 33.5% independent of the presence of MDR. These results indicate that MDR does not severely impair transduction of SCLC...

  6. Induced recovery from near- and far-UV damage in cultured marsupial cells

    International Nuclear Information System (INIS)

    Hoy, D.A.

    1982-01-01

    Colony-forming ability of cultured rat kangaroo cells (Ptk-2) decreases with increasing exposure to light from a daylight fluorescent lamp. After reaching a minimum, survival increases with further exposure, forming a V-shaped survival curve. This increase is inhibited by low concentrations of the protein synthesis inhibitor cycloheximide. The resulting V-shaped survival curve was characterized with respect to several experimental parameters; it appears to be due to an induced repair system dependent on protein synthesis. These results suggest that induced repair, dependent on protein synthesis, in response to fluorescent, near UV, and far UV light damage, is a major repair pathway in Ptk-2 cells, and provides a characterizable system that can elucidate induced repair mechanisms in other mammalian cells

  7. Role of Bax in resveratrol-induced apoptosis of colorectal carcinoma cells

    International Nuclear Information System (INIS)

    Mahyar-Roemer, Mojgan; Köhler, Hans; Roemer, Klaus

    2002-01-01

    The natural plant polyphenol resveratrol present in some foods including grapes, wine, and peanuts, has been implicated in the inhibition, delay, and reversion of cellular events associated with heart diseases and tumorigenesis. Recent work has suggested that the cancer chemoprotective effect of the compound is primarily linked to its ability to induce cell division cycle arrest and apoptosis, the latter possibly through the activation of pro-apoptotic proteins such as Bax. The expression, subcellular localization, and importance of Bax for resveratrol-provoked apoptosis were assessed in human HCT116 colon carcinoma cells and derivatives with both bax alleles inactivated. Low to moderate concentrations of resveratrol induced co-localization of cellular Bax protein with mitochondria, collapse of the mitochondrial membrane potential, activation of caspases 3 and 9, and finally, apoptosis. In the absence of Bax, membrane potential collapse was delayed, and apoptosis was reduced but not absent. Resveratrol inhibited the formation of colonies by both HCT116 and HCT116 bax -/- cells. Resveratrol at physiological doses can induce a Bax-mediated and a Bax-independent mitochondrial apoptosis. Both can limit the ability of the cells to form colonies

  8. ENTRAPMENT OF FLUORESCENT E. COLI CELLS IN ALGINATE GEL

    Directory of Open Access Journals (Sweden)

    T. VINTILA

    2009-05-01

    Full Text Available By this experiment we will demonstrate the possibility to obtain genetically modified microbial strains that can be used as markers in different studies. The trait transferred in this study is the fluorescence in UV light expressed by a gene isolated from jellyfish. This gene was insered into a plasmid carrying ampiciline resistance and in the operon for arabinose fermentation. The plasmid was called pGLO. E coli HB101 K-12, ampicillin resistant colonies has been obtained. The colonies on the LB/amp/ara plate fluoresce green under UV light and the transformed colonies can grow on ampicillin. Transformation efficiency = 362 transformed colonies/ μg DNA. The cells where immobilized by entrapment in alginate gel to study the phenomenon involved in cells immobilization. After immobilization in alginate gel, 5x104 cells of E. coli pGLO / capsule and 1,4 x 105 cells of E. coli HB101/capsule has been found. Fluorescent microscopy revealed the presence of pGLO carrying cells into the capsules. After cultivation of alginate capsules containing E. coli in LB broth, and fluorescent microscopy of the capsule sections, several observations of the phenomenon involved in continuous fermentation using biocatalysts in has been made. These cells grow and migrate to the cortical part of the matrix where they are immobilized.

  9. Apoptosis induced by cold shock in vitro is dependent on cell growth phase.

    Science.gov (United States)

    Soloff, B L; Nagle, W A; Moss, A J; Henle, K J; Crawford, J T

    1987-06-15

    Chinese hamster V79 fibroblast cells were exposed to brief periods of cold but non-freezing temperatures at different points on the population growth curve. Upon rewarming, cells at the transition from logarithmic to stationary growth exhibited apoptosis (programmed cell death). Cells in other stages of growth, or after reentry into logarithmic growth by refeeding, did not exhibit apoptosis. Apoptosis was expressed by marked cytoplasmic blebbing, by a characteristic non-random fragmentation of DNA into nucleosomal-sized pieces, and by loss of colony-forming ability. The data suggest that cold shock served as a stimulus for susceptible cells to undergo apoptosis. Thus, the experiments describe a new in vitro system for studying the mechanisms of apoptosis.

  10. OpenCFU, a new free and open-source software to count cell colonies and other circular objects.

    Science.gov (United States)

    Geissmann, Quentin

    2013-01-01

    Counting circular objects such as cell colonies is an important source of information for biologists. Although this task is often time-consuming and subjective, it is still predominantly performed manually. The aim of the present work is to provide a new tool to enumerate circular objects from digital pictures and video streams. Here, I demonstrate that the created program, OpenCFU, is very robust, accurate and fast. In addition, it provides control over the processing parameters and is implemented in an intuitive and modern interface. OpenCFU is a cross-platform and open-source software freely available at http://opencfu.sourceforge.net.

  11. Colony size, cell number, carbon and nitrogen contents of Phaeocystis pouchetii from western Norway

    NARCIS (Netherlands)

    Verity, Peter G.; Whipple, S. J.; Nejstgaard, J. C.; Alderkamp, A.-C.

    Phaeocystis pouchetii is an ecologically important colony-forming marine phytoplankton species in northern hemisphere cold waters. It plays a central role in the processing of biogeochemically important elements in the upper ocean during spring blooms. Here, we report highly significant quantitative

  12. Pseudomonas aeruginosa forms Biofilms in Acute InfectionIndependent of Cell-to-Cell Signaling

    Energy Technology Data Exchange (ETDEWEB)

    Schaber, J. Andy; Triffo, W.J.; Suh, Sang J.; Oliver, Jeffrey W.; Hastert, Mary C.; Griswold, John A.; Auer, Manfred; Hamood, Abdul N.; Rumbaugh, Kendra P.

    2006-09-20

    Biofilms are bacterial communities residing within a polysaccharide matrix that are associated with persistence and antibiotic resistance in chronic infections. We show that the opportunistic pathogen Pseudomonas aeruginosa forms biofilms within 8 hours of infection in thermally-injured mice, demonstrating that biofilms contribute to bacterial colonization in acute infections. P. aeruginosa biofilms were visualized within burned tissue surrounding blood vessels and adipose cells. Although quorum sensing (QS), a bacterial signaling mechanism, coordinates differentiation of biofilms in vitro, wild type and QS-deficient P. aeruginosa formed similar biofilms in vivo. Our findings demonstrate that P. aeruginosa forms biofilms on specific host tissues independent of QS.

  13. Differences of statin activity in 2D and 3D pancreatic cancer cell cultures

    Directory of Open Access Journals (Sweden)

    Paškevičiūtė M

    2017-11-01

    Full Text Available Miglė Paškevičiūtė,1 Vilma Petrikaitė1,21Department of Drug Chemistry, Faculty of Pharmacy, Lithuanian University of Health Sciences, Kaunas, Lithuania; 2Department of Biothermodynamics and Drug Design, Vilnius University Institute of Biotechnology, Vilnius, LithuaniaPurpose: To evaluate the anticancer activity of lovastatin (LOVA, mevastatin (MEVA, pitavastatin (PITA, and simvastatin (SIMVA in 2D and 3D models of three human pancreatic cancer cell lines (BxPC-3, MIA PaCa-2, and PANC-1.Methods: The effect of statins on cell viability was estimated by 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide test. The activity of statins in 3D pancreatic cancer cell cultures was examined by measuring the size change of spheroids. The type of cell death was identified by cell staining with Hoechst 33342 and propidium iodide. The activity of statins on the clonogenicity of cancer cells was tested by evaluating the effect on the colony-forming ability of cells.Results: The rank order of the activity of tested statins on cell viability was as follows: PITA > SIMVA > LOVA > MEVA. Among the tested statins, PITA had the greatest effect on cell viability (half maximal effective concentration values after 72 h on BxPC-3, MIA PaCa-2, and PANC-1 cells were 1.4±0.4 µM, 1.0±0.2 µM, and 1.0±0.5 µM, respectively. PITA also showed the strongest effect on tumor spheroid growth. Statins suppressed the colony formation of cancer cells. PITA demonstrated the greatest reduction in colony size and number. Apoptosis and necrosis assay results showed that at lower concentrations statins mostly induced cell death through apoptosis, whereas higher concentrations of compounds activated also necrotic processes.Conclusion: Statins, especially PITA, demonstrate an anticancer activity against pancreatic cancer cell lines BxPC-3, MIA PaCa-2, and PANC-1 in both 2D and 3D models.Keywords: HMG-CoA reductase, cell viability, spheroid, apoptosis

  14. Consistent bone marrow-derived cell mobilization following repeated short courses of granulocyte-colony-stimulating factor in patients with amyotrophic lateral sclerosis: results from a multicenter prospective trial.

    Science.gov (United States)

    Tarella, Corrado; Rutella, Sergio; Gualandi, Francesca; Melazzini, Mario; Scimè, Rosanna; Petrini, Mario; Moglia, Cristina; Ulla, Marco; Omedé, Paola; Bella, Vincenzo La; Corbo, Massimo; Silani, Vincenzo; Siciliano, Gabriele; Mora, Gabriele; Caponnetto, Claudia; Sabatelli, Mario; Chiò, Adriano

    2010-01-01

    The aim of this study was to evaluate and characterize the feasibility and safety of bone marrow-derived cell (BMC) mobilization following repeated courses of granulocyte-colony stimulating factor (G-CSF) in patients with amyotrophic lateral sclerosis (ALS). Between January 2006 and March 2007, 26 ALS patients entered a multicenter trial that included four courses of BMC mobilization at 3-month intervals. In each course, G-CSF (5 microg/kg b.i.d.) was administered for four consecutive days; 18% mannitol was also given. Mobilization was monitored by flow cytometry analysis of circulating CD34(+) cells and by in vitro colony assay for clonogenic progenitors. Co-expression by CD34(+) cells of CD133, CD90, CD184, CD117 and CD31 was also assessed. Twenty patients completed the four-course schedule. One patient died and one refused to continue the program before starting the mobilization courses; four discontinued the study protocol because of disease progression. Overall, 89 G-CSF courses were delivered. There were two severe adverse events: one prolactinoma and one deep vein thrombosis. There were no discontinuations as a result of toxic complications. Circulating CD34(+) cells were monitored during 85 G-CSF courses and were always markedly increased; the range of median peak values was 41-57/microL, with no significant differences among the four G-CSF courses. Circulating clonogenic progenitor levels paralleled CD34(+) cell levels. Most mobilized CD34(+) cells co-expressed stem cell markers, with a significant increase in CD133 co-expression. It is feasible to deliver repeated courses of G-CSF to mobilize a substantial number of CD34(+) cells in patients with ALS; mobilized BMC include immature cells with potential clinical usefulness.

  15. Relation between number of hemopoietic stem cells in newborn mice and their radiosensitivity

    International Nuclear Information System (INIS)

    Sutter, T.; Maes, J.; Gerber, G.B.; Leonard, A.

    1985-01-01

    Fractionation of a radiation exposure causes greater damage in newborn mice than a single application since it induces radioresistant foetal hemopoietic stem cells to differentiate prematurely to more radiosensitive adult ones. In the present investigation, it was studied whether other agents that give rise to extensive stem cell destruction also lead to such a change in radiosensitivity. Indeed, treatment with cytostatic drugs which reduces the number of spleen colony forming units (CFU-s) and total cells also diminished the D 0 value of the surviving cells 3 days later. Adriamycin was most effective in causing damage to hemopoietic stem cells and in inducing micronuclei in bone marrow; it also had the most marked action on the D 0 of the surviving stem cells. (orig.)

  16. Exploring the Hypersensitivity of PTEN Deleted Prostate Cancer Stem Cells to WEE1 Tyrosine Kinase Inhibitors

    Science.gov (United States)

    2015-12-01

    performed the clonogenic survival assay using LAPC4 as a model as these cell form well defined colonies compared to C42B cells. This assay revealed that...cells. Future studies with other PTEN deficient models are important to validate the effectiveness of WEE1 inhibitors to tackle recurrent PC...Amplifications and missense mutations Cixutumumab (IMC-A12), Dalotuzumab (MK-0646; h7C10), Linsitinib ( OSI -906) EPHA5 12% LAC, 10% SCLC, 9% SAC, Lung

  17. Transformation of human mesenchymal cells and skin fibroblasts into hematopoietic cells.

    Directory of Open Access Journals (Sweden)

    David M Harris

    Full Text Available Patients with prolonged myelosuppression require frequent platelet and occasional granulocyte transfusions. Multi-donor transfusions induce alloimmunization, thereby increasing morbidity and mortality. Therefore, an autologous or HLA-matched allogeneic source of platelets and granulocytes is needed. To determine whether nonhematopoietic cells can be reprogrammed into hematopoietic cells, human mesenchymal stromal cells (MSCs and skin fibroblasts were incubated with the demethylating agent 5-azacytidine (Aza and the growth factors (GF granulocyte-macrophage colony-stimulating factor and stem cell factor. This treatment transformed MSCs to round, non-adherent cells expressing T-, B-, myeloid-, or stem/progenitor-cell markers. The transformed cells engrafted as hematopoietic cells in bone marrow of immunodeficient mice. DNA methylation and mRNA array analysis suggested that Aza and GF treatment demethylated and activated HOXB genes. Indeed, transfection of MSCs or skin fibroblasts with HOXB4, HOXB5, and HOXB2 genes transformed them into hematopoietic cells. Further studies are needed to determine whether transformed MSCs or skin fibroblasts are suitable for therapy.

  18. Radiosensitivity of mice and its modifiers based on the endogeneous spleen colony formation

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, Jindo; Wagatuma, Kaoru

    1987-02-01

    In irradiated mouse hematopoietic tissue, there is a group of cells which can proliferate and form macroscopic colonies. In the spleen, the colonies formed in this manner are discrete and easy to count. In order to look into a difference of radiosensitivity between male and female and the mechanisms of the modification, such as protective agent and hormones on radiosensitivity, the spleen colony forming (SCF) is used as an indicator of reactions in the x-rays irradiated mice. A linear decrease was found in SCF depended on x-rays dose. From the colony forming after irradiation the male was more radiosensitive than female. AET protected from the injury depended on the radiation dose in male mice, but in female mice, protection effects were not observed. Gonatropin showed protective effects for radiation injury on high dose irradiation both in male and female mice. Adrenaline showed similar effects as Gonatropin. Insuline showed a negative effects of protection on 400 R irradiation, while on 600 R irradiation, protective effects were observed.

  19. Radiosensitizing effect of epothilone B on human epithelial cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Baumgart, T.; Kriesen, S.; Hildebrandt, G.; Manda, K. [Univ. of Rostock (Germany). Dept. of Radiotherapy and Radiation Oncology; Klautke, G.; Fietkau, R. [Friedrich-Alexander-Univ. Erlangen-Nuernberg, Erlangen (Germany). Dept. of Radiation Oncology; Kuznetsov, S.A.; Weiss, D.G. [Univ. of Rostock (Germany). Inst. of Biological Sciences, Cell Biology, and Biosystems Technology

    2012-02-15

    A combined modality treatment employing radiation and chemotherapy plays a central role in the management of solid tumors. In our study, we examined the cytotoxic and radiosensitive effect of the microtubule stabilizer epothilone B on two human epithelial tumor cell lines in vitro and its influence on the microtubule assembly. Cancer cells were treated with epothilone B in proliferation assays and in combination with radiation in colony-forming assays. For the analysis of ionizing radiation-induced DNA damage and the influence of the drug on its repair a {gamma}H2AX foci assay was used. To determine the effect of epothilone B on the microtubule assembly in cells and on purified tubulin, immunofluorescence staining and tubulin polymerization assay, respectively, were conducted. Epothilone B induced a concentration- and application-dependent antiproliferative effect on the cells, with IC{sub 50} values in the low nanomolar range. Colony forming assays showed a synergistic radiosensitive effect on both cell lines which was dependent on incubation time and applied concentration of epothilone B. The {gamma}H2AX assays demonstrated that ionizing radiation combined with the drug resulted in a concentration-dependent increase in the number of double-strand breaks and suggested a reduction in DNA repair capacity. Epothilone B produced enhanced microtubule bundling and abnormal spindle formation as revealed by immunofluorescence microscopy and caused microtubule formation from purified tubulin. The results of this study showed that epothilone B displays cytotoxic antitumor activity at low nanomolar concentrations and also enhances the radiation response in the tumor cells tested; this may be induced by a reduced DNA repair capacity triggered by epothilone B. It was also demonstrated that epothilone B in fact targets microtubules in a more effective manner than paclitaxel. (orig.)

  20. Developmental fate of hematopoietic stem cells: the study of individual hematopoietic clones at the level of antigen-responsive B lymphocytes.

    Science.gov (United States)

    Olovnikova, Natalia I; Drize, Nina J; Ershler, Maxim A; Nifontova, Irina N; Belkina, Elena V; Nikolaeva, Tatiana N; Proskurina, Natalia V; Chertkov, Joseph L

    2003-01-01

    We have shown previously that hematopoiesis in mice reconstituted with retrovirally marked hematopoietic stem cells (HSCs) is provided by multiple, mainly short-lived clones, as measured by retroviral insertion site analysis of individual spleen colony-forming unit (CFU-S)-derived colonies. However, the CFU-S is the relatively early progenitor and the contribution of each CFU-S in the steady-state hematopoiesis is uncertain. Here, we have studied the fate of individual mature B cells, as well as CFU-S, representing the progeny of retrovirally transduced marrow-repopulating cells (MRC). B-cells-generated hybridomas and CFU-S-derived colonies were used to determine the clonal composition of hematolymphopoiesis at the single-cell level. Bone marrow (BM) cells and splenocytes (approximately 1/3-1/2 of spleen at a time) from mice reconstituted with retrovirally marked syngeneic BM cells were repeatedly collected at 3, 10, and 16 months post-transplant. The percentage of retrovirally marked CFU-S and B-cell-produced hybridomas was about 50% at 3 months and decreased to 10-15% at 10 months after reconstitution in spite of stable degree of chimerism. The clonal origin of BM-derived CFU-S and spleen-derived B-cell hybridomas was detected by Southern blot analysis. Overall, DNA obtained from 159 retrovirally marked spleen colonies, 287 hybridomas and 43 BM samples were studied. Multiple simultaneously functioning clones of MRC-derived B cells were observed. The same individual clones among hybridomas and CFU-S were identified in three out of 11 mice. Thus, hematopoiesis is generated by multiple hematopoietic clones some of which can simultaneously contribute to both mature lymphoid cells and myeloid progenitors. These data establish that the stem cell compartment functions by continuously producing progeny, which fully but transiently repopulate all lineages.

  1. Follicle stimulating hormone increases spermatogonial stem cell colonization during in vitro co - culture

    Directory of Open Access Journals (Sweden)

    Reza Narenji Sani

    2013-03-01

    Full Text Available The complex process of spermatogenesis is regulated by various factors. Studies onspermatogonial stem cells(SCCshave provided very important tool to improve herd geneticand different field. 0.2 to 0.3 percent of total cells of seminiferous tubules is consist ofspermatogonial stem cells. To investigate and biomanipulation of these cells, proliferationand viability rate of cells should be increasedin vitro, at first. Follicle stimulating hormone(FSH has been suggested to play a determinant role in the survival of germ cells in additionto increasing spermatogonial proliferation. In this study, thein vitroeffects ofFSHonspermatogonial cell colony formation were investigated. Sertoli and spermatogonial cellswere isolated from 3-5 months old calves. The identity of theSertoli cells and spermatogonialstem cells were confirmed through immunocytochemistry and colony morphology,respectively. Co-cultured Sertoli and spermatogonial cells were treatedwithFSHin differentdose of10, 20 and 40 IU mL-1FSH, before colony assay.Results indicated that,FSHincreasedin vitrocolonization of spermatogonial cells in comparison with control group. In conclusion,usingFSHprovided proper bovine spermatogonial stem cell culture medium forin vitrostudy of these cells.

  2. Enhanced heterologous expression of biologically active human granulocyte colony stimulating factor in transgenic tobacco BY-2 cells by localization to endoplasmic reticulum.

    Science.gov (United States)

    Nair, Nisha R; Chidambareswaren, M; Manjula, S

    2014-09-01

    Tobacco Bright Yellow-2 (BY-2) cells, one of the best characterized cell lines is an attractive expression system for heterologous protein expression. However, the expression of foreign proteins is currently hampered by their low yield, which is partially the result of proteolytic degradation. Human granulocyte colony stimulating factor (hG-CSF) is a hematopoietic cytokine. Recombinant hG-CSF is successfully being used for the treatment of chemotherapy-induced neutropenia in cancer patients. Here, we describe a simple strategy for producing biologically active hG-CSF in tobacco BY-2 cells, localized in the apoplast of BY-2 cells, as well as targeted to the endoplasmic reticulum (ER). ER targeting significantly enhanced recombinant production which scaled to 17.89 mg/l from 4.19 mg/l when expressed in the apoplasts. Southern blotting confirmed the stable integration of hG-CSF in the BY-2 nuclear genome, and the expression of hG-CSF was analysed by Western blotting. Total soluble protein containing hG-CSF isolated from positive calli showed proliferative potential when tested on HL-60 cell lines by MTT assay. We also report the potential of a Fluorescence-activated cell sorting approach for an efficient sorting of the hG-CSF-expressing cell lines, which will enable the generation of homogenous high-producing cell lines.

  3. Delayed reproductive death as a dominant phenotype in cell clones surviving X-irradiation

    International Nuclear Information System (INIS)

    Chang, W.P.; Little, J.B.

    1992-01-01

    Residual damage manifested as reduced cloning efficiency was observed in many of the cloned progeny of Chinese hamster ovary (CHO) cells and human carcinoma SQ-20B cells surviving X-irradiation. This stable phenotype, which we have termed delayed reproductive death, persisted for >50 generations of cell replication post-irradiation. Clones showing this phenotype were aneuploid, and formed colonies with a high proportion of giant cells. By somatic cell hybridization of CHO clones, the delayed reproductive death phenotype was found to be a dominant trait; the cloning efficiency of hybrid clones was persistently depressed, as compared with that of control hybrid cells. These results suggest that delayed reproductive death represents a specific cellular response that may persist in some of the progeny of mammalian cells for long periods after X-irradiation. (author)

  4. Yeast cell differentiation: Lessons from pathogenic and non-pathogenic yeasts.

    Science.gov (United States)

    Palková, Zdena; Váchová, Libuše

    2016-09-01

    Yeasts, historically considered to be single-cell organisms, are able to activate different differentiation processes. Individual yeast cells can change their life-styles by processes of phenotypic switching such as the switch from yeast-shaped cells to filamentous cells (pseudohyphae or true hyphae) and the transition among opaque, white and gray cell-types. Yeasts can also create organized multicellular structures such as colonies and biofilms, and the latter are often observed as contaminants on surfaces in industry and medical care and are formed during infections of the human body. Multicellular structures are formed mostly of stationary-phase or slow-growing cells that diversify into specific cell subpopulations that have unique metabolic properties and can fulfill specific tasks. In addition to the development of multiple protective mechanisms, processes of metabolic reprogramming that reflect a changed environment help differentiated individual cells and/or community cell constituents to survive harmful environmental attacks and/or to escape the host immune system. This review aims to provide an overview of differentiation processes so far identified in individual yeast cells as well as in multicellular communities of yeast pathogens of the Candida and Cryptococcus spp. and the Candida albicans close relative, Saccharomyces cerevisiae. Molecular mechanisms and extracellular signals potentially involved in differentiation processes are also briefly mentioned. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Localized decrease of β-catenin contributes to the differentiation of human embryonic stem cells

    International Nuclear Information System (INIS)

    Lam, Hayley; Patel, Shyam; Wong, Janelle; Chu, Julia; Li, Adrian; Li, Song

    2008-01-01

    Human embryonic stem cells (hESC) are pluripotent, and can be directed to differentiate into different cell types for therapeutic applications. To expand hESCs, it is desirable to maintain hESC growth without differentiation. As hESC colonies grow, differentiated cells are often found at the periphery of the colonies, but the underlying mechanism is not well understood. Here, we utilized micropatterning techniques to pattern circular islands or strips of matrix proteins, and examined the spatial pattern of hESC renewal and differentiation. We found that micropatterned matrix restricted hESC differentiation at colony periphery but allowed hESC growth into multiple layers in the central region, which decreased hESC proliferation and induced hESC differentiation. In undifferentiated hESCs, β-catenin primarily localized at cell-cell junctions but not in the nucleus. The amount of β-catenin in differentiating hESCs at the periphery of colonies or in multiple layers decreased significantly at cell-cell junctions. Consistently, knocking down β-catenin decreased Oct-4 expression in hESCs. These results indicate that localized decrease of β-catenin contributes to the spatial pattern of differentiation in hESC colonies

  6. Mechanisms of growth inhibition of primary prostate epithelial cells following gamma irradiation or photodynamic therapy include senescence, necrosis, and autophagy, but not apoptosis

    International Nuclear Information System (INIS)

    Frame, Fiona M.; Savoie, Huguette; Bryden, Francesca; Giuntini, Francesca; Mann, Vincent M.; Simms, Matthew S.; Boyle, Ross W.; Maitland, Norman J.

    2015-01-01

    In comparison to more differentiated cells, prostate cancer stem-like cells are radioresistant, which could explain radio-recurrent prostate cancer. Improvement of radiotherapeutic efficacy may therefore require combination therapy. We have investigated the consequences of treating primary prostate epithelial cells with gamma irradiation and photodynamic therapy (PDT), both of which act through production of reactive oxygen species (ROS). Primary prostate epithelial cells were cultured from patient samples of benign prostatic hyperplasia and prostate cancer prior to treatment with PDT or gamma irradiation. Cell viability was measured using MTT and alamar blue assay, and cell recovery by colony-forming assays. Immunofluorescence of gamma-H2AX foci was used to quantify DNA damage, and autophagy and apoptosis were assessed using Western blots. Necrosis and senescence were measured by propidium iodide staining and beta-galactosidase staining, respectively. Both PDT and gamma irradiation reduced the colony-forming ability of primary prostate epithelial cells. PDT reduced the viability of all types of cells in the cultures, including stem-like cells and more differentiated cells. PDT induced necrosis and autophagy, whereas gamma irradiation induced senescence, but neither treatment induced apoptosis. PDT and gamma irradiation therefore inhibit cell growth by different mechanisms. We suggest these treatments would be suitable for use in combination as sequential treatments against prostate cancer

  7. Action of caffeine on x-irradiated HeLa cells. VII. Evidence that caffeine enhances expression of potentially lethal radiation damage

    International Nuclear Information System (INIS)

    Beetham, K.L.; Tolmach, L.J.

    1984-01-01

    HeLa cells irradiated with 2 Gy of 220-kV X rays suffer a 60-70% loss of colony-forming ability which is increased to 90% by postirradiation treatment with 10 mM caffeine for 6 hr. The detailed postirradiation patterns of cell death and sister-cell fusion in such cultures and in cultures in which the colony-forming ability was brought to about the same level by treatment with a larger (4 Gy) X-ray dose alone or by longer (48 hr) treatment with 10 mM caffeine alone were recorded by time-lapse cinemicrography. Because the patterns of cell death and fusion differ radically in irradiated and in caffeine-treated cultures, the response of the additional cells killed by the combined treatment can be identified as X-ray induced rather than caffeine induced. The appearance of cultures after several days of incubation confirms the similarity of the post-treatment patterns of proliferation in cultures suffering enhanced killing to those occurring in cultures treated with larger doses of X rays alone. It is concluded that x rays do not sensitize cells to caffeine, but rather that caffeine enhanced the expression of potentially lethal radiation-induced damage

  8. Cellular heredity in haploid cultures of somatic cells. Comprehensive report, April 1975--June 1977

    International Nuclear Information System (INIS)

    Freed, J.J.

    1977-07-01

    This report reviews genetic studies carried out since 1975 on a haploid cultured cell line from frog embryos (ICR 2A). Although a single chromosome set would be expected to facilitate recovery of recessive mutants, experiments suggested that cell culture variants might arise through processes more complex than the selection of simple mutational changes. Therefore, the objectives of the work reported here have been to throw light on just how cell culture variants arise in this system. First, we have continued to characterize the ICR 2A line, with emphasis on stability of karyotype and DNA content. Second, we have studied in detail the origin of two classes of drug-resistant variants. Bromodeoxyuridine resistance of the thymidine deficiency type has been shown to arise through sequential loss of two forms of thymidine-phosphorylating enzyme; loss of the second form of enzyme is complex, suggesting that changes more complex than simple recessive mutations may be involved. Another form of resistance, in which tolerance of high levels of bromodeoxyuridine is found in cells that continue to express thymidine kinase, remains under study. Variants resistant to microtubule inhibitors were isolated. It was found that these haploid strains have properties distinguishing them from analogous resistant strains isolated from diploid mammalian cell cultures in other laboratories. In order to understand better how mutagens are involved in the origin of cell culture variants, we have examined the effect of different forms of DNA repair on the frequency of drug-resistant colonies induced by ultraviolet radiation. Preliminary experiments suggest that the frequency of such colonies is greater when repair takes place through (presumably error-prone) dark repair than when (error-free) photoreversal is allowed to occur. Such experiments can determine whether new phenotypes arise from alterations in DNA, and thus whether, in a broad sense, they are likely to be mutational in nature

  9. The Important Role of FLT3-L in Ex Vivo Expansion of Hematopoietic Stem Cells following Co-Culture with Mesenchymal Stem Cells.

    Science.gov (United States)

    Oubari, Farhad; Amirizade, Naser; Mohammadpour, Hemn; Nakhlestani, Mozhdeh; Zarif, Mahin Nikougoftar

    2015-01-01

    Hematopoietic stem cells (HSCs) transplantation using umbilical cord blood (UCB) has improved during the last decade. Because of cell limitations, several studies focused on the ex vivo expansion of HSCs. Numerous investigations were performed to introduce the best cytokine cocktails for HSC expansion The majority used the Fms-related tyrosine kinase 3 ligand (FLT3-L) as a critical component. According to FLT3-L biology, in this study we have investigated the hypothesis that FLT3-L only effectively induces HSCs expansion in the presence of a mesenchymal stem cell (MSC) feeder. In this experimental study, HSCs and MSCs were isolated from UCB and placenta, respectively. HSCs were cultured in different culture conditions in the presence and absence of MSC feeder and cytokines. After ten days of culture, total nucleated cell count (TNC), cluster of differentiation 34+(CD34(+)) cell count, colony forming unit assay (CFU), long-term culture initiating cell (LTC-IC), homeobox protein B4 (HoxB4) mRNA and surface CD49d expression were evaluated. The fold increase for some culture conditions was compared by the t test. HSCs expanded in the presence of cytokines and MSCs feeder. The rate of expansion in the co-culture condition was two-fold more than culture with cytokines (Pculture condition at a level of 20-fold equal to the presence of stem cell factor (SCF), thrombopoietin (TPO) and FLT3-L without feeder cells. The number of extracted colonies from LTC-IC and CD49d expression compared with a cytokine cocktail condition meaningfully increased (Pculture with MSCs can induce high yield expansion of HSCs and be a substitute for the universal cocktail of SCF, TPO and FLT3-L in feeder-free culture.

  10. Functional modulation of cardiac form through regionally confined cell shape changes.

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    Heidi J Auman

    2007-03-01

    Full Text Available Developing organs acquire a specific three-dimensional form that ensures their normal function. Cardiac function, for example, depends upon properly shaped chambers that emerge from a primitive heart tube. The cellular mechanisms that control chamber shape are not yet understood. Here, we demonstrate that chamber morphology develops via changes in cell morphology, and we determine key regulatory influences on this process. Focusing on the development of the ventricular chamber in zebrafish, we show that cardiomyocyte cell shape changes underlie the formation of characteristic chamber curvatures. In particular, cardiomyocyte elongation occurs within a confined area that forms the ventricular outer curvature. Because cardiac contractility and blood flow begin before chambers emerge, cardiac function has the potential to influence chamber curvature formation. Employing zebrafish mutants with functional deficiencies, we find that blood flow and contractility independently regulate cell shape changes in the emerging ventricle. Reduction of circulation limits the extent of cardiomyocyte elongation; in contrast, disruption of sarcomere formation releases limitations on cardiomyocyte dimensions. Thus, the acquisition of normal cardiomyocyte morphology requires a balance between extrinsic and intrinsic physical forces. Together, these data establish regionally confined cell shape change as a cellular mechanism for chamber emergence and as a link in the relationship between form and function during organ morphogenesis.

  11. Baicalein Induces Apoptosis and Autophagy via Endoplasmic Reticulum Stress in Hepatocellular Carcinoma Cells

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    Zhongxia Wang

    2014-01-01

    Full Text Available Background. Hepatocellular carcinoma (HCC remains a disastrous disease and the treatment for HCC is rather limited. Separation and identification of active compounds from traditionally used herbs in HCC treatment may shed light on novel therapeutic drugs for HCC. Methods. Cell viability and colony forming assay were conducted to determine anti-HCC activity. Morphology of cells and activity of caspases were analyzed. Antiapoptotic Bcl-2 family proteins and JNK were also examined. Levels of unfolded protein response (UPR markers were determined and intracellular calcium was assayed. Small interfering RNAs (siRNAs were used to investigate the role of UPR and autophagy in baicalein-induced cell death. Results. Among four studied flavonoids, only baicalein exhibited satisfactory inhibition of viability and colony formation of HCC cells within water-soluble concentration. Baicalein induced apoptosis via endoplasmic reticulum (ER stress, possibly by downregulating prosurvival Bcl-2 family, increasing intracellular calcium, and activating JNK. CHOP was the executor of cell death during baicalein-induced ER stress while eIF2α and IRE1α played protective roles. Protective autophagy was also triggered by baicalein in HCC cells. Conclusion. Baicalein exhibits prominent anti-HCC activity. This flavonoid induces apoptosis and protective autophagy via ER stress. Combination of baicalein and autophagy inhibitors may represent a promising therapy against HCC.

  12. Direct anti-inflammatory effects of granulocyte colony-stimulating factor (G-CSF) on activation and functional properties of human T cell subpopulations in vitro.

    Science.gov (United States)

    Malashchenko, Vladimir Vladimirovich; Meniailo, Maxsim Evgenievich; Shmarov, Viacheslav Anatolievich; Gazatova, Natalia Dinislamovna; Melashchenko, Olga Borisovna; Goncharov, Andrei Gennadievich; Seledtsova, Galina Victorovna; Seledtsov, Victor Ivanovich

    2018-03-01

    We investigated the direct effects of human granulocyte colony-stimulating factor (G-CSF) on functionality of human T-cell subsets. CD3 + T-lymphocytes were isolated from blood of healthy donors by positive magnetic separation. T cell activation with particles conjugated with antibodies (Abs) to human CD3, CD28 and CD2 molecules increased the proportion of cells expressing G-CSF receptor (G-CSFR, CD114) in all T cell subpopulations studied (CD45RA + /CD197 + naive T cells, CD45RA - /CD197 + central memory T cells, CD45RA - /CD197 - effector memory T cells and CD45RA + /CD197 - terminally differentiated effector T cells). Upon T-cell activation in vitro, G-CSF (10.0 ng/ml) significantly and specifically enhanced the proportion of CD114 + T cells in central memory CD4 + T cell compartment. A dilution series of G-CSF (range, 0.1-10.0 ng/ml) was tested, with no effect on the expression of CD25 (interleukin-2 receptor α-chain) on activated T cells. Meanwhile, G-CSF treatment enhanced the proportion of CD38 + T cells in CD4 + naïve T cell, effector memory T cell and terminally differentiated effector T cell subsets, as well as in CD4 - central memory T cells and terminally differentiated effector T cells. G-CSF did not affect IL-2 production by T cells; relatively low concentrations of G-CSF down-regulated INF-γ production, while high concentrations of this cytokine up-regulated IL-4 production in activated T cells. The data obtained suggests that G-CSF could play a significant role both in preventing the development of excessive and potentially damaging inflammatory reactivity, and in constraining the expansion of potentially cytodestructive T cells. Copyright © 2018 Elsevier Inc. All rights reserved.

  13. Effect of salt on a thermosensitive mutant of Bacillus subtilis deficient in uracil and cell division

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    Miyazaki, N; Nagai, K; Tamura, G

    1976-01-01

    A thermosensitive uracil requiring mutant of Bacillus subtilis Marburg 168 thy trp/sub 2/ ts42 was examined as to the colony forming ability at the permissive and nonpermissive temperatures. The viability of the mutant cells decreased rapidly at the restrictive temperature in the modified Woese's (MW) medium. However, the cells retained viability when sodium succinate or potassium chloride was added to the medium at that temperature although uracil deficiency was unchanged. A little but significant incorporation of adenine-8-/sup 14/C into RNA still continued even after the incorporation of N-acetyl-/sup 3/H-D-glucosamine into acid insoluble fraction of the cells terminated in the MW medium at 48/sup 0/C. Both incorporations as well as increase of absorbance were slowed down in the presence of sodium succinate at 48/sup 0/C. This mutant, ts-42, was more sensitive to deoxycholate (DOC) than the parent strain. The restoration of colony forming ability after the temperature shift back to 37/sup 0/C was suppressed by the addition of DOC to the medium. However, the cell became resistant to DOC when uracil was added to the medium prior to the temperature shift.

  14. DNA amplification is rare in normal human cells

    International Nuclear Information System (INIS)

    Wright, J.A.; Watt, F.M.; Hudson, D.L.; Stark, G.R.; Smith, H.S.; Hancock, M.C.

    1990-01-01

    Three types of normal human cells were selected in tissue culture with three drugs without observing a single amplification event from a total of 5 x 10 8 cells. No drug-resistant colonies were observed when normal foreskin keratinocytes were selected with N-(phosphonacetyl)-L-aspartate or with hydroxyurea or when normal mammary epithelial cells were selected with methotrexate. Some slightly resistant colonies with limited potential for growth were obtained when normal diploid fibroblast cells derived from fetal lung were selected with methotrexate or hydroxyurea but careful copy-number analysis of the dihydrofolate reductase and ribonucleotide reductase genes revealed no evidence of amplification. The rarity of DNA amplification in normal human cells contrasts strongly with the situation in tumors and in established cell lines, where amplification of onogenes and of genes mediating drug resistance is frequent. The results suggest that tumors and cell lines have acquired the abnormal ability to amplify DNA with high frequency

  15. Effect of vitamin D on endothelial progenitor cells function.

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    Yoav Hammer

    Full Text Available Endothelial progenitor cells (EPCs are a population of bone marrow-derived cells, which have an important role in the process of endothelialization and vascular repair following injury. Impairment of EPCs, which occurs in patients with diabetes, was shown to be related to endothelial dysfunction, coronary artery disease (CAD and adverse clinical outcomes. Recent evidence has shown that calcitriol, the active hormone of vitamin D, has a favorable impact on the endothelium and cardiovascular system. There is limited data on the effect of vitamin D on EPCs function.To examine the in vitro effects of Calcitriol on EPCs from healthy subjects and patients with diabetes.Fifty-one patients with type 2 diabetes (60±11 years, 40% women, HbA1C: 9.1±0.8% and 23 healthy volunteers were recruited. EPCs were isolated and cultured with and without calcitriol. The capacity of the cells to form colony-forming units (CFUs, their viability (measured by MTT assay, KLF-10 levels and angiogenic markers were evaluated after 1 week of culture.In diabetic patients, EPC CFUs and cell viability were higher in EPCs exposed to calcitriol vs. EPCs not exposed to calcitriol [EPC CFUs: 1.25 (IQR 1.0-2.0 vs. 0.5 (IQR 0.5-1.9, p < 0.001; MTT:0.62 (IQR 0.44-0.93 vs. 0.52 (IQR 0.31-0.62, p = 0.001]. KLF-10 levels tended to be higher in EPCs exposed to vitamin D, with no differences in angiopoietic markers. In healthy subjects, calcitriol supplementation also resulted in higher cell viability [MTT: 0.23 (IQR 0.11-0.46 vs. 0.19 (0.09-0.39, p = 0.04], but without differences in CFU count or angiopoietic markers.In patients with diabetes mellitus, in vitro vitamin D supplementation improved EPCs capacity to form colonies and viability. Further studies regarding the mechanisms by which vitamin D exerts its effect are required.

  16. Radiosensitivity of spermatogenous epithelium stem cells of mice of different strains and age

    International Nuclear Information System (INIS)

    Konoplyannikova, O.A.; Konoplyannikov, A.G.

    1988-01-01

    In experiments on CBA and BALB/c male mices (3 months of age) and F 1 (CBAxC57BL/6) hybrides (at the age of 3, 12, and 24 months) a difference was noted in the radiosensitivity of spermatogenous epithelium stem cells displayed by the changes in their colony-forming ability to testicular tubules 42 days following local 60 Co-γ-irradiation. The older the hybrid mice the smaller was the number of spermatogenous epithelium stem cells

  17. Enhanced Hematopoietic Stem Cell Self-Renewal-Promoting Ability of Clonal Primary Mesenchymal Stromal/Stem cells Versus Their Osteogenic Progeny.

    Science.gov (United States)

    He, Qiling; Scott Swindle, Claude; Wan, Chao; Flynn, Robert J; Oster, Robert A; Chen, Dongquan; Zhang, Fengjie; Shu, Yinglan; Klug, Christopher A

    2017-02-01

    Long-term self-renewing hematopoietic stem cell (LT-HSC) homeostasis within the bone marrow (BM) of adult mammals is regulated by complex interactions between LT-HSC and a number of niche-associated cell types including mesenchymal stromal/stem cells (MSC), osteoblasts (OB), macrophage, and neuronal cells in close proximity with the vasculature. Here, we cloned and functionally characterized a murine BM MSC subpopulation that was uniformly Nestin + Lepr + Sca-1 + CD146 + and could be stably propagated with high colony-forming unit fibroblast re-cloning efficiency. MSC synergized with SCF and IL-11 to support a 20-fold expansion in true LT-HSC after 10-days of in vitro coculture. Optimal stimulation of LT-HSC expansion was minimally dependent on Notch signaling but was significantly enhanced by global inhibition of Wnt signaling. The self-renewal-promoting activity of MSC was progressively lost when MSC clones were differentiated into mature OB. This suggests that the stage of osteoblast development may significantly impact the ability of osteolineage cells to support LT-HSC homeostasis in vivo. Stem Cells 2017;35:473-484. © 2016 AlphaMed Press.

  18. A chalcone-related small molecule that induces methuosis, a novel form of non-apoptotic cell death, in glioblastoma cells

    OpenAIRE

    Overmeyer, Jean H; Young, Ashley M; Bhanot, Haymanti; Maltese, William A

    2011-01-01

    Abstract Background Methuosis is a unique form of non-apoptotic cell death triggered by alterations in the trafficking of clathrin-independent endosomes, ultimately leading to extreme vacuolization and rupture of the cell. Results Here we describe a novel chalcone-like molecule, 3-(2-methyl-1H- indol-3-yl)-1-(4-pyridinyl)-2-propen-1-one (MIPP) that induces cell death with the hallmarks of methuosis. MIPP causes rapid accumulation of vacuoles derived from macropinosomes, based on time-lapse mi...

  19. Elimination of remaining undifferentiated induced pluripotent stem cells in the process of human cardiac cell sheet fabrication using a methionine-free culture condition.

    Science.gov (United States)

    Matsuura, Katsuhisa; Kodama, Fumiko; Sugiyama, Kasumi; Shimizu, Tatsuya; Hagiwara, Nobuhisa; Okano, Teruo

    2015-03-01

    Cardiac tissue engineering is a promising method for regenerative medicine. Although we have developed human cardiac cell sheets by integration of cell sheet-based tissue engineering and scalable bioreactor culture, the risk of contamination by induced pluripotent stem (iPS) cells in cardiac cell sheets remains unresolved. In the present study, we established a novel culture method to fabricate human cardiac cell sheets with a decreased risk of iPS cell contamination while maintaining viabilities of iPS cell-derived cells, including cardiomyocytes and fibroblasts, using a methionine-free culture condition. When cultured in the methionine-free condition, human iPS cells did not survive without feeder cells and could not proliferate or form colonies on feeder cells or in coculture with cells for cardiac cell sheet fabrication. When iPS cell-derived cells after the cardiac differentiation were transiently cultured in the methionine-free condition, gene expression of OCT3/4 and NANOG was downregulated significantly compared with that in the standard culture condition. Furthermore, in fabricated cardiac cell sheets, spontaneous and synchronous beating was observed in the whole area while maintaining or upregulating the expression of various cardiac and extracellular matrix genes. These findings suggest that human iPS cells are methionine dependent and a methionine-free culture condition for cardiac cell sheet fabrication might reduce the risk of iPS cell contamination.

  20. Chimeric antigen receptor T cells form nonclassical and potent immune synapses driving rapid cytotoxicity.

    Science.gov (United States)

    Davenport, A J; Cross, R S; Watson, K A; Liao, Y; Shi, W; Prince, H M; Beavis, P A; Trapani, J A; Kershaw, M H; Ritchie, D S; Darcy, P K; Neeson, P J; Jenkins, M R

    2018-02-27

    Chimeric antigen receptor T (CAR-T) cells are effective serial killers with a faster off-rate from dying tumor cells than CAR-T cells binding target cells through their T cell receptor (TCR). Here we explored the functional consequences of CAR-mediated signaling using a dual-specific CAR-T cell, where the same cell was triggered via TCR (tcrCTL) or CAR (carCTL). The carCTL immune synapse lacked distinct LFA-1 adhesion rings and was less reliant on LFA to form stable conjugates with target cells. carCTL receptors associated with the synapse were found to be disrupted and formed a convoluted multifocal pattern of Lck microclusters. Both proximal and distal receptor signaling pathways were induced more rapidly and subsequently decreased more rapidly in carCTL than in tcrCTL. The functional consequence of this rapid signaling in carCTL cells included faster lytic granule recruitment to the immune synapse, correlating with faster detachment of the CTL from the target cell. This study provides a mechanism for how CAR-T cells can debulk large tumor burden quickly and may contribute to further refinement of CAR design for enhancing the quality of signaling and programming of the T cell. Copyright © 2018 the Author(s). Published by PNAS.

  1. Follicle stimulating hormone increases spermatogonial stem cell colonization during in vitro co-culture.

    Science.gov (United States)

    Narenji Sani, Reza; Tajik, Parviz; Yousefi, Mohammad Hassan; Movahedin, Mansoureh; Qasemi-Panahi, Babak; Shafiei, Shiva; Ahmadi Hamedani, Mahmood

    2013-01-01

    The complex process of spermatogenesis is regulated by various factors. Studies on spermatogonial stem cells (SCCs) have provided very important tool to improve herd genetic and different field. 0.2 to 0.3 percent of total cells of seminiferous tubules is consist of spermatogonial stem cells. To investigate and biomanipulation of these cells, proliferation and viability rate of cells should be increased in vitro, at first. Follicle stimulating hormone (FSH) has been suggested to play a determinant role in the survival of germ cells in addition to increasing spermatogonial proliferation. In this study, the in vitro effects of FSH on spermatogonial cell colony formation were investigated. Sertoli and spermatogonial cells were isolated from 3-5 months old calves. The identity of the Sertoli cells and spermatogonial stem cells were confirmed through immunocytochemistry and colony morphology, respectively. Co-cultured Sertoli and spermatogonial cells were treated with FSH in different dose of 10, 20 and 40 IU mL(-1) FSH, before colony assay. Results indicated that, FSH increased in vitro colonization of spermatogonial cells in comparison with control group. In conclusion, using FSH provided proper bovine spermatogonial stem cell culture medium for in vitro study of these cells.

  2. In vitro properties and tumorigenicity of radiation-transformed clones of mouse 10T1/2 cells

    International Nuclear Information System (INIS)

    Otsu, Hiroshi; Yasukawa, Mieko; Terasima, Toyozo

    1983-01-01

    Nineteen radiation-induced and one spontaneously developed transformed foci were cloned from mouse 10T1/2 cells. Each clone was grown with normal 10T1/2 cells, and typing (types II and III) was carried out by making reference to the description of Reznikoff et al. Morphological characteristics of foci and their response to co-cultured normal counterparts are described. Some in vitro properties of the clones were examined and the relationship to each focus type is discussed. A reduced serum requirement of transformed clones was not recognized. Soft agar colonies were produced exclusively by type III clones. Tumorigenicity testing of the clones revealed that 93 % of type III clones were tumorigenic upon inoculation into syngeneic mice in an immunosuppressed condition. From these findings, it can be concluded that the tumorigenic potential of radiation-induced transformed cells can be predicted from the ability of the cells to form colonies in agar. (author)

  3. Nimotuzumab promotes radiosensitivity of EGFR-overexpression esophageal squamous cell carcinoma cells by upregulating IGFBP-3

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    Zhao Lei

    2012-12-01

    Full Text Available Abstract Background Epidermal growth factor receptor (EGFR is suggested to predict the radiosensitivity and/or prognosis of human esophageal squamous cell carcinoma (ESCC. The objective of this study was to investigate the efficacy of Nimotuzumab (an anti-EGFR monoclonal antibody on ESCC radiotherapy (RT and underlying mechanisms. Methods Nimotuzumab was administrated to 2 ESCC cell lines KYSE30 and TE-1 treated with RT. Cell growth, colony formation and apoptosis were used to measure anti-proliferation effects. The method of RNA interference was used to investigate the role of insulin-like growth factor binding protein-3 (IGFBP-3 in ESCC cells radiosensitivity treated with Nimotuzumab. In vivo effect of Nimotuzumab on ESCC radiotherapy was done using a mouse xenograft model. Results Nimotuzumab enhanced radiation response of KYSE30 cells (with high EGFR expression in vitro, as evidenced by increased radiation-inhibited cell growth and colony formation and radiation-mediated apoptosis. Mechanism study revealed that Nimotuzumab inhibited phosphorylated EGFR (p-EGFR induced by EGF in KYSE30 cells. In addition, knockdown of IGFBP-3 by short hairpin RNA significantly reduced KYSE30 cells radiosensitivity (PP>0.05. In KYSE30 cell xenografts, Nimotuzumab combined with radiation led to significant tumor growth delay, compared with that of radiation alone (P=0.029, and also with IGFBP-3 up-regulation in tumor tissue. Conclusions Nimotuzumab could enhance the RT effect of ESCC cells with a functional active EGFR pathway. In particular, the increased ESCC radiosensitivity by Nimotuzumab might be dependent on the up-regulation of IGFBP-3 through EGFR-dependent pathway.

  4. Gamma irradiation of the fetus damages the developing hemopoietic microenvironment rather than the hemopoietic progenitor cells

    International Nuclear Information System (INIS)

    Yang, F.T.; Lord, B.I.; Hendry, J.H.

    1995-01-01

    Hemopoiesis is the product of two components: the hemopoietic tissue and the regulatory stromal microenvironment in which it resides. Plutonium-239, incorporated during fetal development in mice, is known to cause deficient hemopoiesis. A predetermined equivalent γ-ray dose has now been used in combination with cross-transplantation experiments to separate these two components and define where the damage arises. It was confirmed that 1.8 Gy γ irradiation at midterm gestation caused a 40% reduction in the hemopoietic stem (spleen colony-forming) cell population of their offspring which persisted to at least 24 weeks of age. Spleen colony formation after sublethal doses of γ rays reflected this reduced complement of endogenous stem cells. The regulatory hemopoietic microenvironment, measured as fibroblastoid colony-forming cells, was similarly depleted. Normal growth of the CFU-S population after transplantation into standard recipients showed that the quality of the stem cell population in the offspring of irradiated mothers was not affected. By contrast, when used as recipients of a bone marrow transplant from either normal or irradiated offspring, the offspring of irradiated mothers were unable to support normal growth: there was a twofold difference in the number of CFU-S per femur for at least 100 days after transplantation. There were 70% fewer CFU-F in the femur 1 month after bone marrow transplantation when the offspring of irradiated mothers were used as transplant recipients compared to when normal offspring were used. This not only confirmed their reduced capacity to host normal stem cells but also indicated that CFU-F in the transplant were unable to compensate for the poor microenvironment in the irradiated offspring hosts. It is concluded that irradiation at midterm gestation damages the developing regulatory microenvironment but not the hemopoietic stem cell population that it hosts. 12 refs., 1 fig., 4 tabs

  5. Differential properties of human ACL and MCL stem cells may be responsible for their differential healing capacity

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    Fu Freddie H

    2011-06-01

    Full Text Available Abstract Background The human anterior cruciate ligament (hACL and medial collateral ligament (hMCL of the knee joint are frequently injured, especially in athletic settings. It has been known that, while injuries to the MCL typically heal with conservative treatment, ACL injuries usually do not heal. As adult stem cells repair injured tissues through proliferation and differentiation, we hypothesized that the hACL and hMCL contain stem cells exhibiting unique properties that could be responsible for the differential healing capacity of the two ligaments. Methods To test the above hypothesis, we derived ligament stem cells from normal hACL and hMCL samples from the same adult donors using tissue culture techniques and characterized their properties using immunocytochemistry, RT-PCR, and flow cytometry. Results We found that both hACL stem cells (hACL-SCs and hMCL stem cells (hMCL-SCs formed colonies in culture and expressed stem cell markers nucleostemin and stage-specific embryonic antigen-4 (SSEA-4. Moreover, both hACL-SCs and hMCL-SCs expressed CD surface markers for mesenchymal stem cells, including CD44 and CD90, but not those markers for vascular cells, CD31, CD34, CD45, and CD146. However, hACL-SCs differed from hMCL-SCs in that the size and number of hACL-SC colonies in culture were much smaller and grew more slowly than hMCL-SC colonies. Moreover, fewer hACL-SCs in cell colonies expressed stem cell markers STRO-1 and octamer-binding transcription factor-4 (Oct-4 than hMCL-SCs. Finally, hACL-SCs had less multi-differentiation potential than hMCL-SCs, evidenced by differing extents of adipogenesis, chondrogenesis, and osteogenesis in the respective induction media. Conclusions This study shows for the first time that hACL-SCs are intrinsically different from hMCL-SCs. We suggest that the differences in their properties contribute to the known disparity in healing capabilities between the two ligaments.

  6. HeLa Cells Containing a Truncated Form of DNA Polymerase Beta are More Sensitized to Alkylating Agents than to Agents Inducing Oxidative Stress.

    Science.gov (United States)

    Khanra, Kalyani; Chakraborty, Anindita; Bhattacharyya, Nandan

    2015-01-01

    The present study was aimed at determining the effects of alkylating and oxidative stress inducing agents on a newly identified variant of DNA polymerase beta (polβ Δ208-304) specific for ovarian cancer. Pol β Δ208-304 has a deletion of exons 11-13 which lie in the catalytic part of enzyme. We compared the effect of these chemicals on HeLa cells and HeLa cells stably transfected with this variant cloned into in pcDNAI/neo vector by MTT, colony forming and apoptosis assays. Polβ Δ208-304 cells exhibited greater sensitivity to an alkylating agent and less sensitivity towards H2O2 and UV when compared with HeLa cells alone. It has been shown that cell death in Pol β Δ208-304 transfected HeLa cells is mediated by the caspase 9 cascade. Exon 11 has nucleotidyl selection activity, while exons 12 and 13 have dNTP selection activity. Hence deletion of this part may affect polymerizing activity although single strand binding and double strand binding activity may remain same. The lack of this part may adversely affect catalytic activity of DNA polymerase beta so that the variant may act as a dominant negative mutant. This would represent clinical significance if translated into a clinical setting because resistance to radiation or chemotherapy during the relapse of the disease could be potentially overcome by this approach.

  7. The Janus-faced roles of Krüppel-like factor 4 in oral squamous cell carcinoma cells.

    Science.gov (United States)

    Li, Wenwen; Liu, Man; Su, Ying; Zhou, Xinying; Liu, Yao; Zhang, Xinyan

    2015-12-29

    Krüppel-like factor 4 (KLF4) is a zinc-finger transcription factor that regulates many essential processes, including development and cell differentiation, proliferation, and apoptosis. Along with these roles in normal cells and tissues, KLF4 has important tumor suppressive and oncogenic functions in some malignancies. However, the roles of KLF4 in oral squamous cell carcinoma remain unclear. This study investigated the epigenetic alterations and possible roles of KLF4 in oral cancer carcinogenesis. Notably, KLF4 expression was significantly decreased in human oral cancer tissues compared with healthy controls, and KLF4 promoter hypermethylation contributed to the suppression of KLF4 expression. KLF4 expression was associated with tumor grade. Its expression was much lower in poorly differentiated oral cancers than in well-differentiated cancer cells. KLF4 exerted its antitumor activity in vitro and/or in vivo by inhibiting cell proliferation, cell cycle progression, cell colony formation and by inducing apoptosis. In addition, KLF4 over-expression promoted oral cancer cell migration and invasion in vitro. Knockdown of KLF4 promoted oral cancer cells growth and colony formation, and simultaneously inhibited cell migration and invasion. Mechanistic studies revealed that MMP-9 might contribute to KLF4-mediated cell migration and invasion. These results provide evidence that KLF4 might play Janus-faced roles in oral cancer carcinogenesis, acting both as a tumor suppressor and as an oncogene.

  8. Transcriptional signature of human adipose tissue-derived stem cells (hASCs) preconditioned for chondrogenesis in hypoxic conditions

    International Nuclear Information System (INIS)

    Pilgaard, L.; Lund, P.; Duroux, M.; Lockstone, H.; Taylor, J.; Emmersen, J.; Fink, T.; Ragoussis, J.; Zachar, V.

    2009-01-01

    Hypoxia is an important factor involved in the control of stem cells. To obtain a better insight into the phenotypical changes brought about by hypoxic preconditioning prior to chondrogenic differentiation; we have investigated growth, colony-forming and chondrogenic capacity, and global transcriptional responses of six adipose tissue-derived stem cell lines expanded at oxygen concentrations ranging from ambient to 1%. The assessment of cell proliferation and colony-forming potential revealed that the hypoxic conditions corresponding to 1% oxygen played a major role. The chondrogenic inducibility, examined by high-density pellet model, however, did not improve on hypoxic preconditioning. While the microarray analysis revealed a distinctive inter-donor variability, the exposure to 1% hypoxia superseded the biological variability and produced a specific expression profile with 2581 significantly regulated genes and substantial functional enrichment in the pathways of cell proliferation and apoptosis. Additionally, exposure to 1% oxygen resulted in upregulation of factors related to angiogenesis and cell growth. In particular, leptin (LEP), the key regulator of body weight and food intake was found to be highly upregulated. In conclusion, the results of this investigation demonstrate the significance of donor demographics and the importance of further studies into the use of regulated oxygen tension as a tool for preparation of ASCs in order to exploit their full potential.

  9. Phytohemagglutinin (PHA) stimulation of peripheral-blood lymphocytes and stem cell take

    Energy Technology Data Exchange (ETDEWEB)

    Astaldi, G. (Blood Research Foundation Center, Tortona, Italy); Karanovic, D.; Vettori, P.P.; Karanovic, J.; Piletic, O.

    1974-01-01

    The effect of PHA-stimulation of peripheral-blood lymphocytes on the spleen-colony formation in irradiated rats was examined. 25-day old Wistar rats underwent total-body irradiation (600 R), and they were used as recipients. On the other hand, 2 and /sup 1///sub 2/ month old untreated Wistar rats were used as donors of peripheral-blood lymphocytes, which were obtained by sedimentation with Dextraven from defibrinated blood. Four rat lots were used. The 1st one did not receive irradiation, and was kept as ''blank control.'' The 2nd one was just irradiated and kept as ''radiated control.'' The 3rd and the 4th rat lots of the series were irradiated, but the former lot was injected i.v. with 5 x 10/sup 7/ peripheral-blood untreated lymphocytes, whereas the fourth lot was injected i.v. with the same amount of lymphocytes, which were previously incubated in vitro for 24 hrs with PHA-M (Difco). The results showed that the PHA-incubation of transplanted peripheral-blood lymphocytes significantly increases the number and size of the macroscopic spleen colonies, in relationship to the colonies which occurs after transplantation of untreated lymphocytes. Histo-cytological observation clearly showed that the colonies formed after injection of mitogen-pretreated peripheral-blood lymphocytes were predominantly of erythroid type and, then, of non-differentiated cells. Only a few of them were of a mixed type, consisting of both undifferentiated cells and erythroid cells.

  10. Development of buffalo (Bubalus bubalis embryonic stem cell lines from somatic cell nuclear transferred blastocysts

    Directory of Open Access Journals (Sweden)

    Syed Mohmad Shah

    2015-11-01

    Full Text Available We developed buffalo embryonic stem cell lines from somatic cell nuclear transfer derived blastocysts, produced by hand-guided cloning technique. The inner cell mass of the blastocyst was cut mechanically using a Microblade and cultured onto feeder cells in buffalo embryonic stem (ES cell culture medium at 38 °C in a 5% CO2 incubator. The stem cell colonies were characterized for alkaline phosphatase activity, karyotype, pluripotency and self-renewal markers like OCT4, NANOG, SOX2, c-Myc, FOXD3, SSEA-1, SSEA-4, TRA-1-60, TRA-1-81 and CD90. The cell lines also possessed the capability to differentiate across all the three germ layers under spontaneous differentiation conditions.

  11. Eckol suppresses maintenance of stemness and malignancies in glioma stem-like cells

    International Nuclear Information System (INIS)

    Hyun, Kyung-Hwan; Yoon, Chang-Hwan; Kim, Rae-Kwon; Lim, Eun-Jung; An, Sungkwan; Park, Myung-Jin; Hyun, Jin-Won; Suh, Yongjoon; Kim, Min-Jung; Lee, Su-Jae

    2011-01-01

    A subpopulation of cancer cells with stem cell properties is responsible for tumor maintenance and progression, and may contribute to resistance to anticancer treatments. Thus, compounds that target cancer stem-like cells could be usefully applied to destroy cancer. In this study, we investigated the effect of Eckol, a phlorotannin compound, on stemness and malignancies in glioma stem-like cells. To determine whether Eckol targets glioma stem-like cells, we examined whether Eckol treatment could change the expression levels of glioma stem-like cell markers and self-renewal-related proteins as well as the sphere forming ability, and the sensitivity to anticancer treatments. Alterations in the malignant properties of sphere-derived cells by Eckol were also investigated by soft-agar colony forming assay, by xenograft assay in nude mice, and by cell invasion assay. Treatment of sphere-forming glioma cells with Eckol effectively decreased the sphere formation as well as the CD133 + cell population. Eckol treatment suppressed expression of the glioma stem-like cell markers and the self-renewal-related proteins without cell death. Moreover, treatment of glioma stem-like cells with Eckol significantly attenuated anchorage-independent growth on soft agar and tumor formation in xenograft mice. Importantly, Eckol treatment effectively reduced the resistance of glioma stem-like cells to ionizing radiation and temozolomide. Treatment of glioma stem-like cells with Eckol markedly blocked both phosphoinositide 3-kinase-Akt and Ras-Raf-1-Erk signaling pathways. These results indicate that the natural phlorotannin Eckol suppresses stemness and malignancies in glioma stem-like cells, and thereby makes glioma stem-like cells more sensitive to anticancer treatments, providing novel therapeutic strategies targeting specifically cancer stem-like cells.

  12. Safety of Pegfilgrastim (Neulasta in Patients with Sickle Cell Trait/Anemia

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    Pashtoon Murtaza Kasi

    2013-01-01

    Full Text Available Pegfilgrastim (Neulasta is a recombinant filgrastim (human granulocyte colony-stimulating factor (G-CSF attached to a polyethylene glycol (PEG molecule and is given as part of chemotherapy regimens that are associated with significant myelosuppression and risk for febrile neutropenia. Prescribing information available on manufacturer’s website for the drug warns us about possible severe sickle cell crises related to the medication but does not report the actual incidence or the use in patients with sickle cell trait. Caution is advised when using it in patients with sickle cell disease. Here we present a case of a Caucasian female with known sickle cell trait (SCT with no prior complications who developed a presumed sickle cell crisis after getting Neulasta, as a part of the chemotherapy regimen used to treat her breast cancer. Based on our literature review, this appears to be the first case report of a patient with SCT developing a sickle cell crisis with the pegylated form of recombinant filgrastim. Given the dearth of literature regarding the use of G-CSF and its related pegylated forms in patients with sickle cell anemia and sickle cell trait, a discussion of potential mechanisms and review of current literature and guidelines is also presented.

  13. The role of autophagy inhibition in the enhanced cytotoxicity of temozolomide on melanoma cell lines

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    O. O. Ryabaya

    2017-01-01

    Full Text Available Background. Despite advantages in treatment of metastatic melanoma it remains resistant to current therapy. Recent evidence indicates that tumor cells could overcome death through autophagy, a process that degrades cellular proteins and organelles to maintain cellular biosynthesis during nutrient deprivation or lack of energy. Objective: to investigate the involvement of autophagy inhibitors chloroquine (CQ and LY-294.002 (LY in temozolomide (TMZ cytotoxicity in human melanoma cell lines.Materials and methods. The study was performed on patient-derived melanoma cell lines Mel Z, Mel IL and Mel MTP. The antiproliferative activity of combined TMZ and autophagy inhibitors treatment was determined by MTT assay and colony-forming assay. Cell cycle analysis, apoptosis activation and expression analysis of key autophagy markers under combined treatment was evaluated.Results. CQ and LY enhanced the cytotoxicity of TMZ and reduced colony formation in 3 melanoma cell lines, moreover both inhibitors increased cell population in G0 / G1 phase of cell cycle in Mel Z, Mel IL cell lines, but not in Mel MTP. CQ and LY synergistically activated apoptosis in all cell lines. The matrix RNA expression analysis of key autophagy genes showed autophagy involvement in enhanced cytotoxicity.Conclusions. Thus, autophagy inhibition on different stages of this process could overcome resistance to TMZ and be applicable as potent target in metastatic melanoma treatment.

  14. Characterization of Lgr6+ Cells as an Enriched Population of Hair Cell Progenitors Compared to Lgr5+ Cells for Hair Cell Generation in the Neonatal Mouse Cochlea

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    Yanping Zhang

    2018-05-01

    Full Text Available Hair cell (HC loss is irreversible because only very limited HC regeneration has been observed in the adult mammalian cochlea. Wnt/β-catenin signaling regulates prosensory cell proliferation and differentiation during cochlear development, and Wnt activation promotes the proliferation of Lgr5+ cochlear HC progenitors in newborn mice. Similar to Lgr5, Lgr6 is also a Wnt downstream target gene. Lgr6 is reported to be present in adult stem cells in the skin, nail, tongue, lung, and mammary gland, and this protein is very important for adult stem cell maintenance in rapidly proliferating organs. Our previous studies showed that Lgr6+ cells are a subpopulation of Lgr5+ progenitor cells and that both Lgr6+ and Lgr5+ progenitors can generate Myosin7a+ HCs in vitro. Thus we hypothesized that Lgr6+ cells are an enriched population of cochlear progenitor cells. However, the detailed distinctions between the Lgr5+ and Lgr6+ progenitors are unclear. Here, we systematically compared the proliferation, HC differentiation, and detailed transcriptome expression profiles of these two progenitor populations. We found that the same number of isolated Lgr6+ progenitors generated significantly more Myosin7a+ HCs compared to Lgr5+ progenitors; however, Lgr5+ progenitors formed more epithelial colonies and more spheres than Lgr6+ progenitors in vitro. Using RNA-Seq, we compared the transcriptome differences between Lgr5+ and Lgr6+ progenitors and identified a list of significantly differential expressed genes that might regulate the proliferation and differentiation of these HC progenitors, including 4 cell cycle genes, 9 cell signaling pathway genes, and 54 transcription factors. In conclusion, we demonstrate that Lgr6+ progenitors are an enriched population of inner ear progenitors that generate more HCs compared to Lgr5+ progenitors in the newborn mouse cochlea, and the our research provides a series of genes that might regulate the proliferation of progenitors

  15. Induced Pluripotent Stem Cell Generation from Blood Cells Using Sendai Virus and Centrifugation.

    Science.gov (United States)

    Rim, Yeri Alice; Nam, Yoojun; Ju, Ji Hyeon

    2016-12-21

    The recent development of human induced pluripotent stem cells (hiPSCs) proved that mature somatic cells can return to an undifferentiated, pluripotent state. Now, reprogramming is done with various types of adult somatic cells: keratinocytes, urine cells, fibroblasts, etc. Early experiments were usually done with dermal fibroblasts. However, this required an invasive surgical procedure to obtain fibroblasts from the patients. Therefore, suspension cells, such as blood and urine cells, were considered ideal for reprogramming because of the convenience of obtaining the primary cells. Here, we report an efficient protocol for iPSC generation from peripheral blood mononuclear cells (PBMCs). By plating the transduced PBMCs serially to a new, matrix-coated plate using centrifugation, this protocol can easily provide iPSC colonies. This method is also applicable to umbilical cord blood mononuclear cells (CBMCs). This study presents a simple and efficient protocol for the reprogramming of PBMCs and CBMCs.

  16. Generation of organized germ layers from a single mouse embryonic stem cell.

    Science.gov (United States)

    Poh, Yeh-Chuin; Chen, Junwei; Hong, Ying; Yi, Haiying; Zhang, Shuang; Chen, Junjian; Wu, Douglas C; Wang, Lili; Jia, Qiong; Singh, Rishi; Yao, Wenting; Tan, Youhua; Tajik, Arash; Tanaka, Tetsuya S; Wang, Ning

    2014-05-30

    Mammalian inner cell mass cells undergo lineage-specific differentiation into germ layers of endoderm, mesoderm and ectoderm during gastrulation. It has been a long-standing challenge in developmental biology to replicate these organized germ layer patterns in culture. Here we present a method of generating organized germ layers from a single mouse embryonic stem cell cultured in a soft fibrin matrix. Spatial organization of germ layers is regulated by cortical tension of the colony, matrix dimensionality and softness, and cell-cell adhesion. Remarkably, anchorage of the embryoid colony from the 3D matrix to collagen-1-coated 2D substrates of ~1 kPa results in self-organization of all three germ layers: ectoderm on the outside layer, mesoderm in the middle and endoderm at the centre of the colony, reminiscent of generalized gastrulating chordate embryos. These results suggest that mechanical forces via cell-matrix and cell-cell interactions are crucial in spatial organization of germ layers during mammalian gastrulation. This new in vitro method could be used to gain insights on the mechanisms responsible for the regulation of germ layer formation.

  17. Indirect immobilized Jagged1 suppresses cell cycle progression and induces odonto/osteogenic differentiation in human dental pulp cells.

    Science.gov (United States)

    Manokawinchoke, Jeeranan; Nattasit, Praphawi; Thongngam, Tanutchaporn; Pavasant, Prasit; Tompkins, Kevin A; Egusa, Hiroshi; Osathanon, Thanaphum

    2017-08-31

    Notch signaling regulates diverse biological processes in dental pulp tissue. The present study investigated the response of human dental pulp cells (hDPs) to the indirect immobilized Notch ligand Jagged1 in vitro. The indirect immobilized Jagged1 effectively activated Notch signaling in hDPs as confirmed by the upregulation of HES1 and HEY1 expression. Differential gene expression profiling using an RNA sequencing technique revealed that the indirect immobilized Jagged1 upregulated genes were mainly involved in extracellular matrix organization, disease, and signal transduction. Downregulated genes predominantly participated in the cell cycle, DNA replication, and DNA repair. Indirect immobilized Jagged1 significantly reduced cell proliferation, colony forming unit ability, and the number of cells in S phase. Jagged1 treated hDPs exhibited significantly higher ALP enzymatic activity, osteogenic marker gene expression, and mineralization compared with control. Pretreatment with a γ-secretase inhibitor attenuated the Jagged1-induced ALP activity and mineral deposition. NOTCH2 shRNA reduced the Jagged1-induced osteogenic marker gene expression, ALP enzymatic activity, and mineral deposition. In conclusion, indirect immobilized Jagged1 suppresses cell cycle progression and induces the odonto/osteogenic differentiation of hDPs via the canonical Notch signaling pathway.

  18. Role of the DNA repair system in increasing the viability of E. coli cells under the action of small UV doses

    Energy Technology Data Exchange (ETDEWEB)

    Kuzin, A M; Vilenchik, M M; Isakov, B K [AN SSSR, Pushchino-na-Oke. Inst. Biologicheskoj Fiziki; AN Kazakhskoj SSR, Alma-Ata. Inst. Botaniki)

    1976-12-01

    The authors studied the action of the ultraviolet light (UV) on the colony-forming ability of E.coli K12-HCR/sup +/ cultured in a meat infusion broth in the presence of glucose. An unusual shape of the curve indicates that the number of viable cells increases under the action of low UV doses. The experiment was repeated seven times, and each time the phenomenon was fully asserted (p 0.01). So it was suggested that low UV doses (about 140 erg/mm/sup 2/) activate the system of dark DNA repair (induction of the synthesis of repair enzymes) which repairs 'spontaneous' DNA defects and increases the number of colony-forming cells.

  19. Induced pluripotent stem cell-derived cardiac progenitors differentiate to cardiomyocytes and form biosynthetic tissues.

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    Nicolas Christoforou

    Full Text Available The mammalian heart has little capacity to regenerate, and following injury the myocardium is replaced by non-contractile scar tissue. Consequently, increased wall stress and workload on the remaining myocardium leads to chamber dilation, dysfunction, and heart failure. Cell-based therapy with an autologous, epigenetically reprogrammed, and cardiac-committed progenitor cell source could potentially reverse this process by replacing the damaged myocardium with functional tissue. However, it is unclear whether cardiac progenitor cell-derived cardiomyocytes are capable of attaining levels of structural and functional maturity comparable to that of terminally-fated cardiomyocytes. Here, we first describe the derivation of mouse induced pluripotent stem (iPS cells, which once differentiated allow for the enrichment of Nkx2-5(+ cardiac progenitors, and the cardiomyocyte-specific expression of the red fluorescent protein. We show that the cardiac progenitors are multipotent and capable of differentiating into endothelial cells, smooth muscle cells and cardiomyocytes. Moreover, cardiac progenitor selection corresponds to cKit(+ cell enrichment, while cardiomyocyte cell-lineage commitment is concomitant with dual expression of either cKit/Flk1 or cKit/Sca-1. We proceed to show that the cardiac progenitor-derived cardiomyocytes are capable of forming electrically and mechanically coupled large-scale 2D cell cultures with mature electrophysiological properties. Finally, we examine the cell progenitors' ability to form electromechanically coherent macroscopic tissues, using a physiologically relevant 3D culture model and demonstrate that following long-term culture the cardiomyocytes align, and form robust electromechanical connections throughout the volume of the biosynthetic tissue construct. We conclude that the iPS cell-derived cardiac progenitors are a robust cell source for tissue engineering applications and a 3D culture platform for pharmacological

  20. Initial stage of transformation of permissive cells by simian virus 40: development of resistance to productive infection.

    Science.gov (United States)

    Hahn, E C; Sauer, G

    1971-07-01

    A quantitative assay has been used to determine the conditions leading to acquisition of resistance of permissive cells to lytic infection. The number of cell colonies surviving infection depends on the occurrence of several cell divisions after infection. High yields of resistant colonies were obtained when infected, confluent cultures were released from contact inhibition 10 to 14 hr after infection. Infection of actively growing cells produced similar results, but halting further division by seeding these growing cells on confluent monolayers prevented the development of colonies. Colony formation was a direct function of multiplicities lower than 5. An inverse killing response was observed with higher multiplicities, yet colonies were produced at a multiplicity of infection as high as 50. Brief exposure of input simian virus 40 to ultraviolet light stimulated colony formation. Irradiation of the virus for longer periods of time led to reduction of colony formation at a rate slower than the rate of inactivation of viral infectivity. It was concluded that resistance is induced by simian virus 40 and that this alteration represents one of the earliest detectable characteristics of the transformation of permissive cells.

  1. Early death, late death and repair factor in three human tumour cell lines

    International Nuclear Information System (INIS)

    Courdi, A.; Gioanni, J.; Mari, D.; Chauvel, P.

    1997-01-01

    The in vivo colony method used to generate survival curves following exposure to ionizing irradiation allows to score large clones, representing surviving cells, and small colonies, representing late reproductive death. By subtraction, early-dying cells can be estimated. In the three human tumour cell lines examined, we have observed that early cell death is a major mode of action of irradiation. The contribution of early cell death to total mortality increases as the dose increases. Moreover, repair due to dose-splitting and delayed plating in densely-inhibited cells is not observed in early-dying cells. (authors)

  2. Suppression of cell death by the secretory form of N-terminal ERC/mesothelin.

    Science.gov (United States)

    Wang, Tegexibaiyin; Kajino, Kazunori; Abe, Masaaki; Tan, Ke; Maruo, Masumi; Sun, Guodong; Hagiwara, Yoshiaki; Maeda, Masahiro; Hino, Okio

    2010-08-01

    ERC/mesothelin is highly expressed in malignant mesothelioma, pancreatic cancer, and ovarian cancer. It is cleaved to a 30 kDa N-terminal secretory form (N-ERC) and a 40 kDa C-terminal membranous form (C-ERC). Several functions have been reported for full-length ERC (full-ERC) and C-ERC/mesothelin, such as in cell adhesion and invasion, stimulation of cell proliferation, and the suppression of cell death. However, there have been no studies to date on the function of secretory N-ERC, despite the fact that it is abundantly secreted into the sera of mesothelioma patients. In this study, we investigated whether N-ERC could function as a secretory factor to stimulate tumor progression. Full-, N, or C-ERC was overexpressed in the human hepatocellular carcinoma cell line Huh7 that lacks endogenous expression of ERC/mesothelin. Changes in the rates of cell proliferation and cell death were determined, and the state of signal transducers was examined using various endpoints: total cell counts, trypan blue exclusion rate, BrdU incorporation rate, TUNEL assay, and the phosphorylation of ERK1/2 and Stat3. In cells overexpressing N-ERC, phosphorylation of ERK1/2 was enhanced and the rate of cell death decreased, leading to the increase of cell number. The culture medium containing the secretory N-ERC also had the activity to increase the number of cells. Our data suggested that one of the full-ERC functions reported previously was mediated by the secretory N-ERC.

  3. Giant morphea-form basal cell carcinoma of the umbilicus: Successful debulking with vismodegib.

    Science.gov (United States)

    Orduz Robledo, Mariana; Lebas, Eve; Reginster, Marie-Annick; Baghaie, Mahmoud; Groves, Sabine; Nikkels, Arjen F

    2018-01-01

    Basal cell carcinoma of the umbilicus is very rare. The nodular subtype is the main representative. Giant basal cell carcinomas represent around 1% of all basal cell carcinomas. The hedgehog pathway inhibitor vismodegib is indicated for advanced basal cell carcinoma and CD56-negative immunostaining seems indicative for successful treatment. A 54-year-old man presented a 10 cm × 14 cm large and 4.5 cm deep morphea-form basal cell carcinoma with faint immunohistochemical CD56 expression arising from the umbilicus. A sequential treatment was initiated with debulking using vismodegib 150 mg per day for 4 months, followed by reconstructive surgery. To the best of our knowledge, this is the first report of a giant basal cell carcinoma of the morphea-form type of the umbilicus. The sequential treatment plan reduces the duration of vismodegib inherent adverse effects and significantly reduces the tumor mass prior to surgery. Besides increasing adherence to vismodegib treatment, this approach facilitates the surgical technique and improves cosmetic outcome.

  4. BTG2 Is Down-Regulated and Inhibits Cancer Stem Cell-Like Features of Side Population Cells in Hepatocellular Carcinoma.

    Science.gov (United States)

    Huang, Chen-Song; Zhai, Jing-Ming; Zhu, Xiao-Xu; Cai, Jian-Peng; Chen, Wei; Li, Jian-Hui; Yin, Xiao-Yu

    2017-12-01

    Our previous study found that B cell translocation gene 2 (BTG2) was hyper-methylated and down-regulated in side population (SP) cells of hepatocellular carcinoma (HCC) cell line. However, its clinical significances and biological impacts on HCC SP cells remained unclear. To investigate the prognostic value of BTG2 gene in HCC and its influences on cancer stem cells (CSCs)-like traits of HCC cell line SP cells. BTG2 expression in human HCC and adjacent non-cancerous tissues was detected by immunohistochemical staining and quantitative real-time PCR, and also obtained from GEO and TCGA data. Its prognostic values were assessed. Its biological influences on HCC cell line SP cells were evaluated using cell viability, cell cycle, plate clone-forming assay, and chemoresistance in vitro and tumorigenicity in vivo. BTG2 expression was significantly suppressed in human HCC compared to adjacent non-cancerous tissues. BTG2 expression was correlated with TNM stage, tumor size and vascular invasion. Lower expression of BTG2 was associated with poorer overall survival and disease-free survival. In vitro, overexpression of BTG2 substantially suppressed cell proliferation and accumulation of HCC cell line SP cells in G0/G1 phase. Colony formation ability was markedly suppressed by BTG2 overexpression. Moreover, sensitivity of HCC cell line SP cells to 5-fluorouracil was substantially increased by overexpression of BTG2. Furthermore, tumorigenicity of HCC cell line SP cells transfected with BTG2 plasmids was significantly reduced in vivo. BTG2 gene could regulate the CSC-like traits of HCC cell line SP cells, and it represented as a molecular prognostic marker for HCC.

  5. Purified Human Dental Pulp Stem Cells Promote Osteogenic Regeneration.

    Science.gov (United States)

    Yasui, T; Mabuchi, Y; Toriumi, H; Ebine, T; Niibe, K; Houlihan, D D; Morikawa, S; Onizawa, K; Kawana, H; Akazawa, C; Suzuki, N; Nakagawa, T; Okano, H; Matsuzaki, Y

    2016-02-01

    Human dental pulp stem/progenitor cells (hDPSCs) are attractive candidates for regenerative therapy because they can be easily expanded to generate colony-forming unit-fibroblasts (CFU-Fs) on plastic and the large cell numbers required for transplantation. However, isolation based on adherence to plastic inevitably changes the surface marker expression and biological properties of the cells. Consequently, little is currently known about the original phenotypes of tissue precursor cells that give rise to plastic-adherent CFU-Fs. To better understand the in vivo functions and translational therapeutic potential of hDPSCs and other stem cells, selective cell markers must be identified in the progenitor cells. Here, we identified a dental pulp tissue-specific cell population based on the expression profiles of 2 cell-surface markers LNGFR (CD271) and THY-1 (CD90). Prospectively isolated, dental pulp-derived LNGFR(Low+)THY-1(High+) cells represent a highly enriched population of clonogenic cells--notably, the isolated cells exhibited long-term proliferation and multilineage differentiation potential in vitro. The cells also expressed known mesenchymal cell markers and promoted new bone formation to heal critical-size calvarial defects in vivo. These findings suggest that LNGFR(Low+)THY-1(High+) dental pulp-derived cells provide an excellent source of material for bone regenerative strategies. © International & American Associations for Dental Research 2015.

  6. Colony mapping: A new technique for monitoring crevice-nesting seabirds

    Science.gov (United States)

    Renner, H.M.; Renner, M.; Reynolds, J.H.; Harping, A.M.A.; Jones, I.L.; Irons, D.B.; Byrd, G.V.

    2006-01-01

    Monitoring populations of auklets and other crevice-nesting seabirds remains problematic, although numerous methods have been attempted since the mid-1960s. Anecdotal evidence suggests several large auklet colonies have recently decreased in both abundance and extent, concurrently with vegetation encroachment and succession. Quantifying changes in the geographical extent of auklet colonies may be a useful alternative to monitoring population size directly. We propose a standardized method for colony mapping using a randomized systematic grid survey with two components: a simple presence/absence survey and an auklet evidence density survey. A quantitative auklet evidence density index was derived from the frequency of droppings and feathers. This new method was used to map the colony on St. George Island in the southeastern Bering Sea and results were compared to previous colony mapping efforts. Auklet presence was detected in 62 of 201 grid cells (each grid cell = 2500 m2) by sampling a randomly placed 16 m2 plot in each cell; estimated colony area = 155 000 m2. The auklet evidence density index varied by two orders of magnitude across the colony and was strongly correlated with means of replicated counts of birds socializing on the colony surface. Quantitatively mapping all large auklet colonies is logistically feasible using this method and would provide an important baseline for monitoring colony status. Regularly monitoring select colonies using this method may be the best means of detecting changes in distribution and population size of crevice-nesting seabirds. ?? The Cooper Ornithological Society 2006.

  7. Mitochondrial DNA deletion mutations in adult mouse cardiac side population cells

    International Nuclear Information System (INIS)

    Lushaj, Entela B.; Lozonschi, Lucian; Barnes, Maria; Anstadt, Emily; Kohmoto, Takushi

    2012-01-01

    We investigated the presence and potential role of mitochondrial DNA (mtDNA) deletion mutations in adult cardiac stem cells. Cardiac side population (SP) cells were isolated from 12-week-old mice. Standard polymerase chain reaction (PCR) was used to screen for the presence of mtDNA deletion mutations in (a) freshly isolated SP cells and (b) SP cells cultured to passage 10. When present, the abundance of mtDNA deletion mutation was analyzed in single cell colonies. The effect of different levels of deletion mutations on SP cell growth and differentiation was determined. MtDNA deletion mutations were found in both freshly isolated and cultured cells from 12-week-old mice. While there was no significant difference in the number of single cell colonies with mtDNA deletion mutations from any of the groups mentioned above, the abundance of mtDNA deletion mutations was significantly higher in the cultured cells, as determined by quantitative PCR. Within a single clonal cell population, the detectable mtDNA deletion mutations were the same in all cells and unique when compared to deletions of other colonies. We also found that cells harboring high levels of mtDNA deletion mutations (i.e. where deleted mtDNA comprised more than 60% of total mtDNA) had slower proliferation rates and decreased differentiation capacities. Screening cultured adult stem cells for mtDNA deletion mutations as a routine assessment will benefit the biomedical application of adult stem cells.

  8. Increased cell survival by inhibition of BRCA1 using an antisense approach in an estrogen responsive ovarian carcinoma cell line

    International Nuclear Information System (INIS)

    Annab, Lois A; Hawkins, Rebecca E; Solomon, Greg; Barrett, J Carl; Afshari, Cynthia A

    2000-01-01

    -day period (Fig. 2a). The BRCA1 antisense population also exhibited a threefold to sixfold increase in cell growth compared with control cells in the presence of estrogen treatment. BG-1 BRCA1 antisense clones demonstrated a similar response to pooled population studies, enhanced growth with estrogen, and failure to die upon estrogen depletion (Fig. 2b). The BRCA1 antisense clones were further examined for other associated tumorigenic properties. All of the antisense clones were able to form colonies in soft agar (2-23 colonies per 10 4 cells plated; data not shown), whereas control clones were deficient in their ability to form colonies (0-0.8 colonies per 10 4 cells plated). Table 1 shows, in the presence of estrogen, the clone with the lowest levels of BRCA1 (AS-4) produced significantly more colonies (133 ± 17.9 colonies per 10 4 cells plated) than the control clone (NEO; 6 ± 3.1 colonies per 10 4 cells plated). Clones AS-4 and NEO were also injected with matrigel subcutaneously into ovariectomized athymic mice. Almost twice as many sites were positive for the AS-4 clone (14 out of 14) as for the NEO clone (eight out of 14) 42 days after injection. In addition, BRCA1 antisense tumors averaged twice the size of control tumors. The BRCA1 reduced cells also formed tumors with half the latency of control cells in the presence of implanted estrogen (11 days versus 21 days until tumor formation). The present studies show that reduction in BRCA1 levels, using an antisense retroviral vector in the estrogen dependent BG-1 ovarian carcinoma cell line, contributes to confirmation of the hypothesis that BRCA1 plays a pivotal role in the balance between cell death and cell proliferation. BRCA1 RNA and protein levels were successfully reduced in populations and isolated clones of antisense infected BG-1 cells. Decreased BRCA1 levels rescued the BG-1 cells from growth arrest or cell death in adverse growth conditions in monolayer or soft agar conditions. Furthermore, a BRCA1

  9. The impact of donor characteristics on the immune cell composition of mixture allografts of granulocyte-colony-stimulating factor-mobilized marrow harvests and peripheral blood harvests.

    Science.gov (United States)

    Wang, Yu-Tong; Zhao, Xiang-Yu; Zhao, Xiao-Su; Xu, Lan-Ping; Zhang, Xiao-Hui; Wang, Yu; Liu, Kai-Yan; Chang, Ying-Jun; Huang, Xiao-Jun

    2015-12-01

    The association of donor characteristics with immune cell composition in allografts remains poorly understood. In this retrospective study, the effects of donor characteristics on immune cell composition in allografts were investigated. The correlations of donor characteristics with the immune cell composition in mixture allografts of granulocyte-colony-stimulating factor-mobilized marrow harvests and peripheral blood harvests of 390 healthy donors (male, 240; female, 150; median age, 40 years old) were analyzed. The median doses of CD3+ T cells, CD4+ T cells, CD8+ T cells, CD3+CD4-CD8- T cells, and monocytes in mixture allografts were 160.57 × 10(6), 89.29 × 10(6), 56.16 × 10(6), 10.87 × 10(6), and 137.94 × 10(6)/kg, respectively. Multivariate analysis showed that younger donor age was associated with a higher dose of CD3+ T cells (p = 0.006), CD3+CD8+ T cells (p donor weight with CD3+ T cells (p blood lymphocyte pre-peripheral blood apheresis was correlated with the yield of CD3+ T cells (p blood monocyte count before marrow harvest predicted the monocyte dose (p = 0.002). The results suggested that older and overweight donors should not be chosen. The monocyte and lymphocyte counts before harvest could predict the yield of immune cells in allografts. © 2015 AABB.

  10. Short-term exposure of umbilical cord blood CD34+ cells to granulocyte-macrophage colony-stimulating factor early in culture improves ex vivo expansion of neutrophils.

    Science.gov (United States)

    Marturana, Flavia; Timmins, Nicholas E; Nielsen, Lars K

    2011-03-01

    Despite the availability of modern antibiotics/antimycotics and cytokine support, neutropenic infection accounts for the majority of chemotherapy-associated deaths. While transfusion support with donor neutrophils is possible, cost and complicated logistics make such an option unrealistic on a routine basis. A manufactured neutrophil product could enable routine prophylactic administration of neutrophils, preventing the onset of neutropenia and substantially reducing the risk of infection. We examined the use of pre-culture strategies and various cytokine/modulator combinations to improve neutrophil expansion from umbilical cord blood (UCB) hematopoietic stem and progenitor cells (HPC). Enriched UCB HPC were cultured using either two-phase pre-culture strategies or a single phase using various cytokine/modulator combinations. Outcome was assessed with respect to numerical expansion, cell morphology, granulation and respiratory burst activity. Pre-culture in the absence of strong differentiation signals (e.g. granulocyte colony-stimulating factor; G-CSF) failed to provide any improvement to final neutrophil yields. Similarly, removal of differentiating cells during pre-culture failed to improve neutrophil yields to an appreciable extent. Of the cytokine/modulator combinations, the addition of granulocyte-macrophage (GM)-colony-stimulating factor (CSF) alone gave the greatest increase. In order to avoid production of monocytes, it was necessary to remove GM-CSF on day 5. Using this strategy, neutrophil expansion improved 2.7-fold. Although all cytokines and culture strategies employed have been reported previously to enhance HPC expansion, we found that the addition of GM-CSF alone was sufficient to improve total cell yields maximally. The need to remove GM-CSF on day 5 to avoid monocyte differentiation highlights the context and time-dependent complexity of exogenous signaling in hematopoietic cell differentiation and growth.

  11. Effects of Granulocyte-Macrophage Colony-Stimulating (GM-CSF Factor on Corneal Epithelial Cells in Corneal Wound Healing Model.

    Directory of Open Access Journals (Sweden)

    Chang Rae Rho

    Full Text Available Granulocyte-macrophage colony-stimulating factor (GM-CSF is a pleiotropic cytokine that activates granulocyte and macrophage cell lineages. It is also known to have an important function in wound healing. This study investigated the effect of GM-CSF in wound healing of human corneal epithelial cells (HCECs. We used human GM-CSF derived from rice cells (rice cell-derived recombinant human GM-CSF; rhGM-CSF. An in vitro migration assay was performed to investigate the migration rate of HCECs treated with various concentrations of rhGM-CSF (0.1, 1.0, and 10.0 μg/ml. MTT assay and flow cytometric analysis were used to evaluate the proliferative effect of rhGM-CSF. The protein level of p38MAPK was analyzed by western blotting. For in vivo analysis, 100 golden Syrian hamsters were divided into four groups, and their corneas were de-epithelialized with alcohol and a blade. The experimental groups were treated with 10, 20, or 50 μg/ml rhGM-CSF four times daily, and the control group was treated with phosphate-buffered saline. The corneal wound-healing rate was evaluated by fluorescein staining at the initial wounding and 12, 24, 36, and 48 hours after epithelial debridement. rhGM-CSF accelerated corneal epithelial wound healing both in vitro and in vivo. MTT assay and flow cytometric analysis revealed that rhGM-CSF treatment had no effects on HCEC proliferation. Western blot analysis demonstrated that the expression level of phosphorylated p38MAPK increased with rhGM-CSF treatment. These findings indicate that rhGM-CSF enhances corneal wound healing by accelerating cell migration.

  12. Both systemic and local application of Granulocyte-colony stimulating factor (G-CSF is neuroprotective after retinal ganglion cell axotomy

    Directory of Open Access Journals (Sweden)

    Dietz Gunnar PH

    2009-05-01

    Full Text Available Abstract Background The hematopoietic Granulocyte-Colony Stimulating Factor (G-CSF plays a crucial role in controlling the number of neutrophil progenitor cells. Its function is mediated via the G-CSF receptor, which was recently found to be expressed also in the central nervous system. In addition, G-CSF provided neuroprotection in models of neuronal cell death. Here we used the retinal ganglion cell (RGC axotomy model to compare effects of local and systemic application of neuroprotective molecules. Results We found that the G-CSF receptor is robustly expressed by RGCs in vivo and in vitro. We thus evaluated G-CSF as a neuroprotectant for RGCs and found a dose-dependent neuroprotective effect of G-CSF on axotomized RGCs when given subcutaneously. As stem stell mobilization had previously been discussed as a possible contributor to the neuroprotective effects of G-CSF, we compared the local treatment of RGCs by injection of G-CSF into the vitreous body with systemic delivery by subcutaneous application. Both routes of application reduced retinal ganglion cell death to a comparable extent. Moreover, G-CSF enhanced the survival of immunopurified RGCs in vitro. Conclusion We thus show that G-CSF neuroprotection is at least partially independent of potential systemic effects and provide further evidence that the clinically applicable G-CSF could become a treatment option for both neurodegenerative diseases and glaucoma.

  13. Highly active antiretroviral therapy normalizes the function of progenitor cells in human immunodeficiency virus-infected patients

    DEFF Research Database (Denmark)

    Dam Nielsen, S.; Ersbøll, A. K.; Mathiesen, L.

    1998-01-01

    -infected patients were determined prior to HAART and after 2, 4, 8, and 12 weeks of therapy. The mean number of colony-forming units (cells) per milliliter (cfu/mL) was 15.0 prior to HAART vs. 109.8 in healthy controls (P.../mL eliminated the differences between HIV-infected patients and controls. Significant increases in numbers of CD34 cells were not detected. Of importance, the cloning efficiency of CD34 cells increased from 1.7% prior to therapy to a peak at 18.7% (P=.003). In conclusion, HAART normalized CD34 cell function...

  14. Hypoxia is a key regulator of limbal epithelial stem cell growth and differentiation

    DEFF Research Database (Denmark)

    Bath, Chris; Yang, Sufang; Muttuvelu, Danson

    2013-01-01

    The aim of this study was to determine whether the growth and differentiation of limbal epithelial stem cell cultures could be controlled through manipulation of the oxygen tension. Limbal epithelial cells were isolated from corneoscleral disks, and cultured using either feeder cells in a growth......, progression through cell cycle, colony forming efficiency (CFE), and expression of stem cell (ABCG2 and p63α) and differentiation (CK3) markers was determined throughout the culture period of up to 18 days. Low oxygen levels favored a stem cell phenotype with a lower proliferative rate, high CFE......, and a relatively higher expression of ABCG2 and p63α, while higher levels of oxygen led not only to decreased CFE but also to increased proportion of differentiated cells positive for CK3. Hypoxic cultures may thus potentially improve stem cell grafts for cultured limbal epithelial transplantation (CLET)....

  15. Expression of p89c-Mybex9b, an alternatively spliced form of c-Myb, is required for proliferation and survival of p210BCR/ABL-expressing cells

    International Nuclear Information System (INIS)

    Manzotti, G; Mariani, S A; Corradini, F; Bussolari, R; Cesi, V; Vergalli, J; Ferrari-Amorotti, G; Fragliasso, V; Soliera, A R; Cattelani, S; Raschellà, G; Holyoake, T L; Calabretta, B

    2012-01-01

    The c-Myb gene encodes the p75 c-Myb isoform and less-abundant proteins generated by alternatively spliced transcripts. Among these, the best known is p c-Mybex9b , which contains 121 additional amino acids between exon 9 and 10, in a domain involved in protein–protein interactions and negative regulation. In hematopoietic cells, expression of p c-Mybex9b accounts for 10–15% of total c-Myb; these levels may be biologically relevant because modest changes in c-Myb expression affects proliferation and survival of leukemic cells and lineage choice and frequency of normal hematopoietic progenitors. In this study, we assessed biochemical activities of p c-Mybex9b and the consequences of perturbing its expression in K562 and primary chronic myeloid leukemia (CML) progenitor cells. Compared with p75 c-Myb , p c-Mybex9b is more stable and more effective in transactivating Myb-regulated promoters. Ectopic expression of p c-Mybex9b enhanced proliferation and colony formation and reduced imatinib (IM) sensitivity of K562 cells; conversely, specific downregulation of p c-Mybex9b reduced proliferation and colony formation, enhanced IM sensitivity of K562 cells and markedly suppressed colony formation of CML CD34 + cells, without affecting the levels of p75 c-Myb . Together, these studies indicate that expression of the low-abundance p c-Mybex9b isoform has an important role for the overall biological effects of c-Myb in BCR/ABL-transformed cells

  16. "The good into the pot, the bad into the crop!"--a new technology to free stem cells from feeder cells.

    Directory of Open Access Journals (Sweden)

    Annette Schneider

    Full Text Available A variety of embryonic and adult stem cell lines require an initial co-culturing with feeder cells for non-differentiated growth, self renewal and maintenance of pluripotency. However for many downstream ES cell applications the feeder cells have to be considered contaminations that might interfere not just with the analysis of experimental data but also with clinical application and tissue engineering approaches. Here we introduce a novel technique that allows for the selection of pure feeder-freed stem cells, following stem cell proliferation on feeder cell layers. Complete and reproducible separation of feeder and embryonic stem cells was accomplished by adaptation of an automated cell selection system that resulted in the aspiration of distinct cell colonies or fraction of colonies according to predefined physical parameters. Analyzing neuronal differentiation we demonstrated feeder-freed stem cells to exhibit differentiation potentials comparable to embryonic stem cells differentiated under standard conditions. However, embryoid body growth as well as differentiation of stem cells into cardiomyocytes was significantly enhanced in feeder-freed cells, indicating a feeder cell dependent modulation of lineage differentiation during early embryoid body development. These findings underline the necessity to separate stem and feeder cells before the initiation of in vitro differentiation. The complete separation of stem and feeder cells by this new technology results in pure stem cell populations for translational approaches. Furthermore, a more detailed analysis of the effect of feeder cells on stem cell differentiation is now possible, that might facilitate the identification and development of new optimized human or genetically modified feeder cell lines.

  17. Intrinsic radiosensitivity and PLD repair in osteosarcoma cell lines

    International Nuclear Information System (INIS)

    Sugimoto, M.; Toguchida, J.; Kotoura, Y.; Yamamuro, T.; Utsumi, H.

    1992-01-01

    The response to radiation of seven osteosarcoma cell lines was analysed by in vitro colony-forming assay and compared with that of eight human fibroblast strains. The values of D 0 , the surviving fraction after 2 Gy (S2Gy), and the mean inactivation dose (D-bar) of osteosarcoma cells in log-phase culture were significantly higher than those of fibroblast strains (p<0.01). PLD (potentially lethal damage) repair of osteosarcoma cells evaluated in the plateau phase of growth showed great variation for enhancement of survival, although all of the values were maximised within 12 h after irradiation. In the osteosarcoma, intrinsic radiosensitivity in vitro reflected the clinical response to radiation. However, the capacity for PLD repair might not be a good indicator for predicting the results of radiation therapy. (author)

  18. Sodium butyrate stimulates cellular recovery from UV damage in xeroderma pigmentosum cells belonging to complementation group F

    International Nuclear Information System (INIS)

    Nishigori, Chikako; Takebe, Hiraku

    1987-01-01

    Possible stimulation of the DNA repair capacity by sodium butyrate in normal and xeroderma pigmentosum (XP) cells was investigated. XP cells belonging to the complementation group F showed considerable stimulation of DNA repair by sodium butyrate in terms of both the amount of unscheduled DNA synthesis (UDS) and the colony-forming ability after UV irradiation. UDS in XP cells belonging to the complementation group A was not enhanced, while normal cells showed slight enhancement, but less than that of XP F cells. In XP A, XP C, and normal cells, sodium butyrate treatment enhanced the killing effect of UV irradiation. The residual repair capacity in XP F cells appeared to be stimulated by sodium butyrate. (author)

  19. THE POTENTIAL ROLE OF ENDOGENOUS STEM CELLS IN REGENERATION OF THE INNER EAR

    Science.gov (United States)

    Martinez-Monedero, Rodrigo; Oshima, Kazuo; Heller, Stefan; Edge, Albert S.B.

    2007-01-01

    Stem cells in various mammalian tissues retain the capacity to renew themselves and may be able to restore damaged tissue. Their existence has been proven by genetic tracer studies that demonstrate their differentiation into multiple tissue types and by their ability to self-renew through proliferation. Stem cells from the adult nervous system proliferate to form clonal floating colonies called spheres in vitro, and recent studies have demonstrated sphere formation by cells in the cochlea in addition to the vestibular system and the auditory ganglia, indicating that these tissues contain cells with stem cell properties. The presence of stem cells in the inner ear raises the hope of regeneration of mammalian inner ear cells but is difficult to correlate with the lack spontaneous regeneration seen in the inner ear after tissue damage. Loss of stem cells postnatally in the cochlea may correlate with the loss of regenerative capacity and may limit our ability to stimulate regeneration. Retention of sphere forming capacity in adult vestibular tissues suggests that the limited capacity for repair may be attributed to the continued presence of progenitor cells. Future strategies for regeneration must consider the distribution of endogenous stem cells in the inner ear and whether cells with the capacity for regeneration are retained. PMID:17321086

  20. Nitric oxide and superoxide dismutase modulate endothelial progenitor cell function in type 2 diabetes mellitus.

    Science.gov (United States)

    Hamed, Saher; Brenner, Benjamin; Aharon, Anat; Daoud, Deeb; Roguin, Ariel

    2009-10-30

    The function of endothelial progenitor cells (EPCs), which are key cells in vascular repair, is impaired in diabetes mellitus. Nitric oxide (NO) and reactive oxygen species can regulate EPC functions. EPCs tolerate oxidative stress by upregulating superoxide dismutase (SOD), the enzyme that neutralizes superoxide anion (O2-). Therefore, we investigated the roles of NO and SOD in glucose-stressed EPCs. The functions of circulating EPCs from patients with type 2 diabetes were compared to those from healthy individuals. Healthy EPCs were glucose-stressed, and then treated with insulin and/or SOD. We assessed O2- generation, NO production, SOD activity, and their ability to form colonies. EPCs from diabetic patients generated more O2-, had higher NAD(P)H oxidase and SOD activity, but lower NO bioavailability, and expressed higher mRNA and protein levels of p22-phox, and manganese SOD and copper/zinc SOD than those from the healthy individuals. Plasma glucose and HbA1c levels in the diabetic patients were correlated negatively with the NO production from their EPCs. SOD treatment of glucose-stressed EPCs attenuated O2- generation, restored NO production, and partially restored their ability to form colonies. Insulin treatment of glucose-stressed EPCs increased NO production, but did not change O2- generation and their ability to form colonies. However, their ability to produce NO and to form colonies was fully restored after combined SOD and insulin treatment. Our data provide evidence that SOD may play an essential role in EPCs, and emphasize the important role of antioxidant therapy in type 2 diabetic patients.

  1. Regeneration of hemopoietic precursor cells in spleen organ cultures from irradiated mice: influence of genotype of cells injected and of the spleen microenvironment

    International Nuclear Information System (INIS)

    von Melchner, H.; Lieschke, G.J.

    1981-01-01

    The regeneration of hemopoietic precursor cells (colony-forming cells, CFC) was monitored in spleen organ cultures from lethally irradiated mice injected with 10(7) normal syngeneic or allogeneic bone marrow cells. The important role of the microenvironment in supporting hemopoiesis was confirmed by the failure of mutant S1/S1d spleens to support CFC regeneration in organ cultures. However, the extent and quality of the CFC regeneration was clearly dependent on the genetic properties of the injected cells. Evidence for this was obtained from the regeneration patterns of various CFC types in organ cultured spleens derived from different mouse donor-recipient strain combinations (CBA/CBA, CBA/C57BL, CBA/BALB/c, C57BL/C57BL, C57BL/CBA, C57BL/BALB/c) that maintained the differences in the bone marrow frequency of various CFC types characteristic of the donor strain

  2. Highly sensitive in vitro methods for detection of residual undifferentiated cells in retinal pigment epithelial cells derived from human iPS cells.

    Directory of Open Access Journals (Sweden)

    Takuya Kuroda

    Full Text Available Human induced pluripotent stem cells (hiPSCs possess the capabilities of self-renewal and differentiation into multiple cell types, and they are free of the ethical problems associated with human embryonic stem cells (hESCs. These characteristics make hiPSCs a promising choice for future regenerative medicine research. There are significant obstacles, however, preventing the clinical use of hiPSCs. One of the most obvious safety issues is the presence of residual undifferentiated cells that have tumorigenic potential. To locate residual undifferentiated cells, in vivo teratoma formation assays have been performed with immunodeficient animals, which is both costly and time-consuming. Here, we examined three in vitro assay methods to detect undifferentiated cells (designated an in vitro tumorigenicity assay: soft agar colony formation assay, flow cytometry assay and quantitative real-time polymerase chain reaction assay (qRT-PCR. Although the soft agar colony formation assay was unable to detect hiPSCs even in the presence of a ROCK inhibitor that permits survival of dissociated hiPSCs/hESCs, the flow cytometry assay using anti-TRA-1-60 antibody detected 0.1% undifferentiated hiPSCs that were spiked in primary retinal pigment epithelial (RPE cells. Moreover, qRT-PCR with a specific probe and primers was found to detect a trace amount of Lin28 mRNA, which is equivalent to that present in a mixture of a single hiPSC and 5.0×10⁴ RPE cells. Our findings provide highly sensitive and quantitative in vitro assays essential for facilitating safety profiling of hiPSC-derived products for future regenerative medicine research.

  3. Evolutionary cell biology: functional insight from "endless forms most beautiful".

    Science.gov (United States)

    Richardson, Elisabeth; Zerr, Kelly; Tsaousis, Anastasios; Dorrell, Richard G; Dacks, Joel B

    2015-12-15

    In animal and fungal model organisms, the complexities of cell biology have been analyzed in exquisite detail and much is known about how these organisms function at the cellular level. However, the model organisms cell biologists generally use include only a tiny fraction of the true diversity of eukaryotic cellular forms. The divergent cellular processes observed in these more distant lineages are still largely unknown in the general scientific community. Despite the relative obscurity of these organisms, comparative studies of them across eukaryotic diversity have had profound implications for our understanding of fundamental cell biology in all species and have revealed the evolution and origins of previously observed cellular processes. In this Perspective, we will discuss the complexity of cell biology found across the eukaryotic tree, and three specific examples of where studies of divergent cell biology have altered our understanding of key functional aspects of mitochondria, plastids, and membrane trafficking. © 2015 Richardson et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  4. Cell-cycle synchronisation of bloodstream forms of Trypanosoma brucei using Vybrant DyeCycle Violet-based sorting.

    Science.gov (United States)

    Kabani, Sarah; Waterfall, Martin; Matthews, Keith R

    2010-01-01

    Studies on the cell-cycle of Trypanosoma brucei have revealed several unusual characteristics that differ from the model eukaryotic organisms. However, the inability to isolate homogenous populations of parasites in distinct cell-cycle stages has limited the analysis of trypanosome cell division and complicated the understanding of mutant phenotypes with possible impact on cell-cycle related events. Although hydroxyurea-induced cell-cycle arrest in procyclic and bloodstream forms has been applied recently with success, such block-release protocols can complicate the analysis of cell-cycle regulated events and have the potential to disrupt important cell-cycle checkpoints. An alternative approach based on flow cytometry of parasites stained with Vybrant DyeCycle Orange circumvents this problem, but is restricted to procyclic form parasites. Here, we apply Vybrant Dyecycle Violet staining coupled with flow cytometry to effectively select different cell-cycle stages of bloodstream form trypanosomes. Moreover, the sorted parasites remain viable, although synchrony is rapidly lost. This method enables cell-cycle enrichment of populations of trypanosomes in their mammal infective stage, particularly at the G1 phase.

  5. FogBank: a single cell segmentation across multiple cell lines and image modalities.

    Science.gov (United States)

    Chalfoun, Joe; Majurski, Michael; Dima, Alden; Stuelten, Christina; Peskin, Adele; Brady, Mary

    2014-12-30

    Many cell lines currently used in medical research, such as cancer cells or stem cells, grow in confluent sheets or colonies. The biology of individual cells provide valuable information, thus the separation of touching cells in these microscopy images is critical for counting, identification and measurement of individual cells. Over-segmentation of single cells continues to be a major problem for methods based on morphological watershed due to the high level of noise in microscopy cell images. There is a need for a new segmentation method that is robust over a wide variety of biological images and can accurately separate individual cells even in challenging datasets such as confluent sheets or colonies. We present a new automated segmentation method called FogBank that accurately separates cells when confluent and touching each other. This technique is successfully applied to phase contrast, bright field, fluorescence microscopy and binary images. The method is based on morphological watershed principles with two new features to improve accuracy and minimize over-segmentation. First, FogBank uses histogram binning to quantize pixel intensities which minimizes the image noise that causes over-segmentation. Second, FogBank uses a geodesic distance mask derived from raw images to detect the shapes of individual cells, in contrast to the more linear cell edges that other watershed-like algorithms produce. We evaluated the segmentation accuracy against manually segmented datasets using two metrics. FogBank achieved segmentation accuracy on the order of 0.75 (1 being a perfect match). We compared our method with other available segmentation techniques in term of achieved performance over the reference data sets. FogBank outperformed all related algorithms. The accuracy has also been visually verified on data sets with 14 cell lines across 3 imaging modalities leading to 876 segmentation evaluation images. FogBank produces single cell segmentation from confluent cell

  6. Induction of L-form-like cell shape change of Bacillus subtilis under microculture conditions.

    Science.gov (United States)

    Shingaki, Ryuji; Kasahara, Yasuhiro; Iwano, Megumi; Kuwano, Masayoshi; Takatsuka, Tomomasa; Inoue, Tetsuyoshi; Kokeguchi, Susumu; Fukui, Kazuhiro

    2003-09-01

    A remarkable cell shape change was observed in Bacillus subtilis strain 168 under microculture conditions on CI agar medium (Spizizen's minimal medium supplemented with a trace amount of yeast extract and Casamino acids). Cells cultured under a cover glass changed in form from rod-shaped to spherical, large and irregular shapes that closely resembled L-form cells. The cell shape change was observed only with CI medium, not with Spizizen's minimum medium alone or other rich media. The whole-cell protein profile of cells grown under cover glass and cells grown on CI agar plates differed in several respects. Tandem mass analysis of nine gel bands which differed in protein expression between the two conditions showed that proteins related to nitrate respiration and fermentation were expressed in the shape-changed cells grown under cover glass. The cell shape change of CI cultures was repressed when excess KNO3 was added to the medium. Whole-cell protein analysis of the normal rod-shaped cells grown with 0.1% KNO3 and the shape-changed cells grown without KNO3 revealed that the expression of the branched-chain alpha-keto acid dehydrogenase complex (coded by the bfmB gene locus) was elevated in the shape-changed cells. Inactivation of the bfmB locus resulted in the repression of cell shape change, and cells in which bfmB expression was induced by IPTG did show changes in shape. Transmission electron microscopy of ultrathin sections demonstrated that the shape-changed cells had thin walls, and plasmolysis of cells fixed with a solution including 0.1 M sucrose was observed. Clarifying the mechanism of thinning of the cell wall may lead to the development of a new type of cell wall biosynthetic inhibitor.

  7. Cellular function reinstitution of offspring red blood cells cloned from the sickle cell disease patient blood post CRISPR genome editing

    Directory of Open Access Journals (Sweden)

    Jianguo Wen

    2017-06-01

    Full Text Available Abstract Background Sickle cell disease (SCD is a disorder of red blood cells (RBCs expressing abnormal hemoglobin-S (HbS due to genetic inheritance of homologous HbS gene. However, people with the sickle cell trait (SCT carry a single allele of HbS and do not usually suffer from SCD symptoms, thus providing a rationale to treat SCD. Methods To validate gene therapy potential, hematopoietic stem cells were isolated from the SCD patient blood and treated with CRISPR/Cas9 approach. To precisely dissect genome-editing effects, erythroid progenitor cells were cloned from single colonies of CRISPR-treated cells and then expanded for simultaneous gene, protein, and cellular function studies. Results Genotyping and sequencing analysis revealed that the genome-edited erythroid progenitor colonies were converted to SCT genotype from SCD genotype. HPLC protein assays confirmed reinstallation of normal hemoglobin at a similar level with HbS in the cloned genome-edited erythroid progenitor cells. For cell function evaluation, in vitro RBC differentiation of the cloned erythroid progenitor cells was induced. As expected, cell sickling assays indicated function reinstitution of the genome-edited offspring SCD RBCs, which became more resistant to sickling under hypoxia condition. Conclusions This study is an exploration of genome editing of SCD HSPCs.

  8. Knock-down of NDRG2 sensitizes cervical cancer Hela cells to cisplatin through suppressing Bcl-2 expression

    International Nuclear Information System (INIS)

    Liu, Junye; Guo, Guozhen; Yang, Le; Zhang, Jian; Zhang, Jing; Chen, Yongbin; Li, Kangchu; Li, Yurong; Li, Yan; Yao, Libo

    2012-01-01

    NDRG2, a member of N-Myc downstream regulated gene family, plays some roles in cellular stress, cell differentiation and tumor suppression. We have found that NDRG2 expression in cervical cancer Hela cells increases significantly upon stimulation with cisplatin, the most popular chemotherapeutic agent currently used for the treatment of advanced cervical cancer. This interesting phenomenon drove us to evaluate the role of NDRG2 in chemosensitivity of Hela cells. In the present study, RNA interference was employed to down-regulate NDRG2 expression in Hela cells. RT-PCR and Western blot were used to detect expression of NDRG2, Bcl-2 and Bax in cancer cells. Real-time PCR was applied to detect miR-15b and miR-16 expression levels. Drug sensitivity was determined with MTT assay. Cell cloning efficiency was evaluated by Colony-forming assay. Apoptotic cells were detected with annexin V staining and flow cytometry. In vitro drug sensitivity assay revealed that suppression of NDRG2 could sensitize Hela cells to cisplatin. Down-regulation of NDRG2 didn’t influence the colony-forming ability but promoted cisplatin-induced apoptosis of Hela cells. Inhibition of NDRG2 in Hela cells was accompanied by decreased Bcl-2 protein level. However, Bcl-2 mRNA level was not changed in Hela cells with down-regulation of NDRG2. Further study indicated that miR-15b and miR-16, two microRNAs targetting Bcl-2, were significantly up-regulated in NDRG2-suppressed Hela cells. These data suggested that down-regulation of NDRG2 could enhance sensitivity of Hela cells to cisplatin through inhibiting Bcl-2 protein expression, which might be mediated by up-regulating miR-15b and miR-16

  9. PSMB4 promotes multiple myeloma cell growth by activating NF-κB-miR-21 signaling

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Peihao; Guo, Honggang [Department of Hematology, Navy General Hospital, Beijing 100048 (China); Li, Guangchao [School of Bioscience and Bioengineering, South China University of Technology, Guangzhou 510006 (China); Han, Siqi [Department of Medical Oncology, Jinling Hospital, Nanjing 210002 (China); Luo, Fei [Department of Stomatology, Jinling Hospital, Nanjing 210002 (China); Liu, Yi, E-mail: liuyi2033@163.com [Department of Hematology, Navy General Hospital, Beijing 100048 (China)

    2015-03-06

    Proteasomal subunit PSMB4, was recently identified as potential cancer driver genes in several tumors. However, the regulatory mechanism of PSMB4 on carcinogenesis process remains unclear. In this study, we investigated the expression and roles of PSMB4 in multiple myeloma (MM). We found a significant up-regulation of PSMB4 in MM plasma and cell lines. Ectopic overexpression of PSMB4 promoted cell growth and colony forming ability of MM cells, whereas inhibition of PSMB4 led to a decrease of such events. Furthermore, our results demonstrated the up-regulation of miR-21 and a positive correlation between the levels of miR-21 and PSMB4 in MM. Re-expression of miR-21 markedly rescued PSMB4 knockdown-mediated suppression of cell proliferation and clone-formation. Additionally, while enforced expression of PSMB4 profoundly increased NF-κB activity and the level of miR-21, PSMB4 knockdown or NF-κB inhibition suppressed miR-21 expression in MM cells. Taken together, our results demonstrated that PSMB4 regulated MM cell growth in part by activating NF-κB-miR-21 signaling, which may represent promising targets for novel specific therapies. - Highlights: • First reported upregulation of PSMB4 in MM plasma and cell lines. • PSMB4 promoted MM cell growth and colony forming ability. • Further found miR-21 was up-regulated by PSMB4 in MM plasma and cell lines. • PSMB4-induced miR-21 expression was modulated by NF-κB. • PSMB4-NF-κB-miR-21 axis may be potential therapeutic targets of MM.

  10. Isolation and characterization of string-forming female germline stem cells from ovaries of neonatal mice.

    Science.gov (United States)

    Liu, Jing; Shang, Dantong; Xiao, Yao; Zhong, Pei; Cheng, Hanhua; Zhou, Rongjia

    2017-09-29

    Germline stem cells are essential in the generation of both male and female gametes. In mammals, the male testis produces sperm throughout the entire lifetime, facilitated by testicular germline stem cells. Oocyte renewal ceases in postnatal or adult life in mammalian females, suggesting that germline stem cells are absent from the mammalian ovary. However, studies in mice, rats, and humans have recently provided evidence for ovarian female germline stem cells (FGSCs). A better understanding of the role of FGSCs in ovaries could help improve fertility treatments. Here, we developed a rapid and efficient method for isolating FGSCs from ovaries of neonatal mice. Notably, our FGSC isolation method could efficiently isolate on average 15 cell "strings" per ovary from mice at 1-3 days postpartum. FGSCs isolated from neonatal mice displayed the string-forming cell configuration at mitosis ( i.e. a "stringing" FGSC (sFGSC) phenotype) and a disperse phenotype in postnatal mice. We also found that sFGSCs undergo vigorous mitosis especially at 1-3 days postpartum. After cell division, the sFGSC membranes tended to be connected to form sFGSCs. Moreover, F-actin filaments exhibited a cell-cortex distribution in sFGSCs, and E-cadherin converged in cell-cell connection regions, resulting in the string-forming morphology. Our new method provides a platform for isolating FGSCs from the neonatal ovary, and our findings indicate that FGCSs exhibit string-forming features in neonatal mice. The sFGSCs represent a valuable resource for analysis of ovary function and an in vitro model for future clinical use to address ovarian dysfunction. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  11. Hematopoietic Stem and Progenitor Cell Expansion in Contact with Mesenchymal Stromal Cells in a Hanging Drop Model Uncovers Disadvantages of 3D Culture.

    Science.gov (United States)

    Schmal, Olga; Seifert, Jan; Schäffer, Tilman E; Walter, Christina B; Aicher, Wilhelm K; Klein, Gerd

    2016-01-01

    Efficient ex vivo expansion of hematopoietic stem cells with a concomitant preservation of stemness and self-renewal potential is still an unresolved ambition. Increased numbers of methods approaching this issue using three-dimensional (3D) cultures were reported. Here, we describe a simplified 3D hanging drop model for the coculture of cord blood-derived CD34(+) hematopoietic stem and progenitor cells (HSPCs) with bone marrow-derived mesenchymal stromal cells (MSCs). When seeded as a mixed cell suspension, MSCs segregated into tight spheroids. Despite the high expression of niche-specific extracellular matrix components by spheroid-forming MSCs, HSPCs did not migrate into the spheroids in the initial phase of coculture, indicating strong homotypic interactions of MSCs. After one week, however, HSPC attachment increased considerably, leading to spheroid collapse as demonstrated by electron microscopy and immunofluorescence staining. In terms of HSPC proliferation, the conventional 2D coculture system was superior to the hanging drop model. Furthermore, expansion of primitive hematopoietic progenitors was more favored in 2D than in 3D, as analyzed in colony-forming assays. Conclusively, our data demonstrate that MSCs, when arranged with a spread (monolayer) shape, exhibit better HSPC supportive qualities than spheroid-forming MSCs. Therefore, 3D systems are not necessarily superior to traditional 2D culture in this regard.

  12. Use of Limiting Dilution Method for Isolation of Nucleus Pulposus Mesenchymal Stem/Progenitor Cells and Effects of Plating Density on Biological Characteristics and Plasticity

    Directory of Open Access Journals (Sweden)

    Linghan Lin

    2017-01-01

    Full Text Available Objectives. To evaluate the effects of the limiting dilution method and plating density in rat nucleus pulposus mesenchymal stem/progenitor cells (NPMSCs. Materials and Methods. Nucleus pulposus tissues were isolated from 12-week-old male Sprague-Dawley rats and NPMSCs were isolated using limiting dilution method. Cells were then classified into 3 groups according to plating density. Cell morphologies were observed, and colony-forming units, migration abilities, proliferative capacities, cell cycle percentages, multilineage differentiation capacities, stem cell biomarker expression levels, and immunophenotyping were also examined in each group. Results. Low density group (LD had higher morphological homogeneity, stronger colony-forming ability, higher cell proliferation capacity, and enhanced cell migration ability relative to the other two groups (p<0.05. Moreover, LD had more cells entering S phase, with fewer cells arrested in G0/G1 phase (p<0.05. While all three density groups showed a multilineage differentiation potential, LD showed a higher degree of observed and semiquantified lineage specific staining (p<0.05. Furthermore, LD displayed higher expression levels of stem cell biomarkers (Nanog, Oct4, and Sox2 and showed higher percentages of CD29+, CD44+, and CD90+ cells (p<0.05 following flow cytometry analysis. Conclusions. Limiting dilution method is suggested when isolating NPMSCs as a means of improving cell activity and plasticity.

  13. Lhx2 expression promotes self-renewal of a distinct multipotential hematopoietic progenitor cell in embryonic stem cell-derived embryoid bodies.

    Directory of Open Access Journals (Sweden)

    Lina Dahl

    Full Text Available The molecular mechanisms regulating the expansion of the hematopoietic system including hematopoietic stem cells (HSCs in the fetal liver during embryonic development are largely unknown. The LIM-homeobox gene Lhx2 is a candidate regulator of fetal hematopoiesis since it is expressed in the fetal liver and Lhx2(-/- mice die in utero due to severe anemia. Moreover, expression of Lhx2 in embryonic stem (ES cell-derived embryoid bodies (EBs can lead to the generation of HSC-like cell lines. To further define the role of this transcription factor in hematopoietic regulation, we generated ES cell lines that enabled tet-inducible expression of Lhx2. Using this approach we observed that Lhx2 expression synergises with specific signalling pathways, resulting in increased frequency of colony forming cells in developing EB cells. The increase in growth factor-responsive progenitor cells directly correlates to the efficiency in generating HSC-like cell lines, suggesting that Lhx2 expression induce self-renewal of a distinct multipotential hematopoietic progenitor cell in EBs. Signalling via the c-kit tyrosine kinase receptor and the gp130 signal transducer by IL-6 is necessary and sufficient for the Lhx2 induced self-renewal. While inducing self-renewal of multipotential progenitor cells, expression of Lhx2 inhibited proliferation of primitive erythroid precursor cells and interfered with early ES cell commitment, indicating striking lineage specificity of this effect.

  14. Radiation response of spermatogonial stem cells in the mouse

    International Nuclear Information System (INIS)

    Bootsma, A.L.

    1978-01-01

    Spermatogonial stem cells are able to repopulate the testis by forming clones that elongate along the walls of the seminiferous tubules depleted of spermatogenetic cells as a result of an irradiation. The surviving number of stem cells after irradiation was estimated by determining the fraction of repopulated tubules in cross-sections of the testis 11 weeks after irradiation. This fraction, called the 'repopulation index', is assumed to be directly proportional to the number of surviving stem cells. The response of spermatogonial stem cells in the CBA mouse to 1-MeV fission neutrons was investigated. Radioresistant, colony forming stem cells in the mouse testis move into a much more radiosensitive phase of their cell cycle shortly after irradiation. This is demonstrated in publication II in experiments in which total doses of 300 rad of neutrons and 1200 rad of X-rays were split into two equal fractions. The radiation response of spermatogonial stem cells in the mouse which survived various doses of fission neutrons 24 hours before was studied in publication III. Twenty four hours after a dose of 150 rad of fission neutrons all first-dose survivors have moved from a radioresistant (D 0 89+-4 rad in this study) towards a radiosensitive phase of their cell cycle. Spermatogonial stem cells which survive a neutron dose of 150 rad all belong to a radioresistant stem cell population in the seminiferous epithelium. The data in publication IV show that during the first 26 days after a dose of 150 rad of neutrons the stem cell population first increases and then slowly decreases its radiosensitivity, to stay fixed at a relatively high level. (Auth.)

  15. Generation and characterization of p53 null transformed hepatic progenitor cells: oval cells give rise to hepatocellular carcinoma.

    Science.gov (United States)

    Dumble, Melissa L; Croager, Emma J; Yeoh, George C T; Quail, Elizabeth A

    2002-03-01

    Oval cells are bipotential liver stem cells able to differentiate into hepatocytes and bile duct epithelia. In normal adult liver oval cells are quiescent, existing in low numbers around the periportal region, and proliferate following severe, prolonged liver trauma. There is evidence implicating oval cells in the development of hepatocellular carcinoma, and hence the availability of an immortalized oval cell line would be invaluable for the study of liver cell lineage differentiation and carcinogenesis. A novel approach in the generation of cell lines is the use of the p53 knockout mouse. Absence of p53 allows a cell to cycle past the normal Hayflick limit, rendering it immortalized, although subsequent genetic alterations are thought necessary for transformation. p53 knockout mice were fed a choline-deficient, ethionine-supplemented diet, previously shown to increase oval cell numbers in wild-type mice. The oval cells were isolated by centrifugal elutriation and maintained in culture. Colonies of hepatic cells were isolated and characterized with respect to phenotype, growth characteristics and tumorigenicity. Analysis of gene expression by Northern blotting and immunocytochemistry suggests they are oval-like cells by virtue of albumin and transferrin expression, as well as the oval cell markers alpha fetoprotein, M(2)-pyruvate kinase and A6. Injection into athymic nude mice shows the cell lines are capable of forming tumors which phenotypically resemble hepatocellular carcinoma. Thus, the use of p53 null hepatic cells successfully generated immortalized and tumorigenic hepatic stem cell lines. The results presented support the idea that deleting p53 allows immortalization and contributes to the transformation of the oval-like cell lines. Further, the tumorigenic status of the cell lines is direct evidence for the participation of oval cells in the formation of hepatocellular carcinoma.

  16. Effects of gamma radiation on the OM431 human ocular melanoma cell line

    International Nuclear Information System (INIS)

    Logani, S.; Cho, A.S.; Su, L.D.; Withers, H.R.; McBride, W.H.; Hall, M.O.; Lee, D.A.; Milani, J.K.; Straatsma, B.R.

    1995-01-01

    In order to determine the dose responsiveness to radiation of ocular melanoma, we conducted an in vitro dose-response study on a monolayer cell culture using a clonogenic assay. The effects on cell survival were determined relative to unirradiated controls. A human epithelioid ocular melanoma cell line, OM431, was maintained in tissue culture and serial dilutions of viable cells were plated in flasks, allowed to settle and attach for 48 h, and subsequently irradiated with 1-10 Gy in single fractions. After 2 weeks, the number of reproducing clones (forming colonies with greater than 32 cells or five generations) were counted. The surviving fractions of cells were plotted on a cell survival curve using the linear quadratic model. The survival curve showed a large initial shoulder followed by an exponential decline in growth. Our data suggest that the OM431 ocular melanoma cell line responds to irradiation in a manner similar to other melanoma cell lines and is relatively radioresistent especially at lower doses. (author)

  17. The role of the DNA repair system in increasing the viability of E.coli cells under the action of small UV doses

    International Nuclear Information System (INIS)

    Kuzin, A.M.; Vilenchik, M.M.; Isakov, B.K.; AN Kazakhskoj SSR, Alma-Ata. Inst. Botaniki)

    1976-01-01

    The authors studied the action of the ultraviolet light (UV) on the colony-forming ability of E.coli K12-HCR + cultured in a meat infusion broth in the presence of glucose. An unusual shape of the curve indicates that the number of viable cells increases under the action of low UV doses. The experiment was repeated seven times, and each time the phenomenon was fully asserted (p 0.01). So it was suggested that low UV doses (about 140 erg/mm 2 ) activate the system of dark DNA repair (induction of the synthesis of repair enzymes) which repairs 'spontaneous' DNA defects and increases the number of colony-forming cells. (orig.) [de

  18. Anti-proliferative effects of T cells expressing a ligand-based chimeric antigen receptor against CD116 on CD34+ cells of juvenile myelomonocytic leukemia

    Directory of Open Access Journals (Sweden)

    Yozo Nakazawa

    2016-03-01

    Full Text Available Abstract Background Juvenile myelomonocytic leukemia (JMML is a fatal, myelodysplastic/myeloproliferative neoplasm of early childhood. Patients with JMML have mutually exclusive genetic abnormalities in granulocyte-macrophage colony-stimulating factor (GM-CSF receptor (GMR, CD116 signaling pathway. Allogeneic hematopoietic stem cell transplantation is currently the only curative treatment option for JMML; however, disease recurrence is a major cause of treatment failure. We investigated adoptive immunotherapy using GMR-targeted chimeric antigen receptor (CAR for JMML. Methods We constructed a novel CAR capable of binding to GMR via its ligand, GM-CSF, and generated piggyBac transposon-based GMR CAR-modified T cells from three healthy donors and two patients with JMML. We further evaluated the anti-proliferative potential of GMR CAR T cells on leukemic CD34+ cells from six patients with JMML (two NRAS mutations, three PTPN11 mutations, and one monosomy 7, and normal CD34+ cells. Results GMR CAR T cells from healthy donors suppressed the cytokine-dependent growth of MO7e cells, but not the growth of K562 and Daudi cells. Co-culture of healthy GMR CAR T cells with CD34+ cells of five patients with JMML at effector to target ratios of 1:1 and 1:4 for 2 days significantly decreased total colony growth, regardless of genetic abnormality. Furthermore, GMR CAR T cells from a non-transplanted patient and a transplanted patient inhibited the proliferation of respective JMML CD34+ cells at onset to a degree comparable to healthy GMR CAR T cells. Seven-day co-culture of GMR CAR T cells resulted in a marked suppression of JMML CD34+ cell proliferation, particularly CD34+CD38− cell proliferation stimulated with stem cell factor and thrombopoietin on AGM-S3 cells. Meanwhile, GMR CAR T cells exerted no effects on normal CD34+ cell colony growth. Conclusions Ligand-based GMR CAR T cells may have anti-proliferative effects on stem and progenitor cells in JMML.

  19. Cell survival after the combined action of manganese (MnCl2) and X-rays in synchronized Chinese hamster cells

    International Nuclear Information System (INIS)

    Skreb, Y.; Nagy, B.

    1984-01-01

    The interactions between the effects of manganese chloride and X-rays were studied in synchronized populations of V79 Chinese hamster fibroblasts. The cells were selected by shaking off asynchronous cultures for detachment of mitotic cells which were plated in petri dishes and exposed to various treatments. Irradiation was carried out with a Philips RT-100 X-ray unit. A final concentration of 0.25 mM MnCl 2 was used. The main parameter was the colony forming ability of the surviving cell fraction. When MnCl 2 was administered over 1 h, its toxicity was low regardless of the phase of the cell cycle. Administered separately, 2 Gy irradiation produced only a slight decrease in survival, less marked in the S phase. However, the two agents together induced a synergistic inhibition of the surviving fraction in the S phase when the metal was given immediately after irradiation. If manganese wad administered 3 h after irradiation the two inhibitory effects apparently remained only additive. It seems that MnCl 2 can impair some repair processes starting immediately after irradiation. (orig.)

  20. Mutator/hypermutable fetal/juvenile metakaryotic stem cells and human colorectal carcinogenesis.

    Directory of Open Access Journals (Sweden)

    Lohith G. Kini

    2013-10-01

    Full Text Available Adult age-specific colorectal cancer incidence rates increase exponentially from maturity, reach a maximum, then decline in extreme old age. Armitage and Doll (1957 postulated that the exponential increase resulted from n mutations occurring throughout adult life in normal cells at risk that initiated the growth of a preneoplastic colony in which subsequent m mutations promoted one of the preneoplastic cells at risk to form a lethal neoplasia. We have reported cytologic evidence that these cells at risk are fetal/juvenile organogenic, then preneoplastic metakaryotic stem cells. Metakaryotic cells display stem-like behaviors of both symmetric and asymmetric nuclear divisions and peculiarities such as bell shaped nuclei and amitotic nuclear fission that distinguish them from embryonic, eukaryotic stem cells. Analyses of mutant colony sizes and numbers in adult lung epithelia supported the inferences that the metakaryotic organogenic stem cells are constitutively mutator/hypermutable and that their contributions to cancer initiation are limited to the fetal/juvenile period. We have amended the two-stage model of Armitage and Doll and incorporated these several inferences in a computer program CancerFit v.5.0. We compared the expectations of the amended model to adult (15-104 yr age-specific colon cancer rates for European American males born 1890-99 and observed remarkable concordance. When estimates of normal colonic fetal/juvenile APC and OAT gene mutation rates (~2-5 x 10-5 per stem cell doubling and preneoplastic colonic gene loss rates (~ 8 x 10-3 were applied, the model was in accordance only for the values of n = 2 and m = 4 or 5.