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Sample records for defined cell populations

  1. CD34 defines an osteoprogenitor cell population in mouse bone marrow stromal cells

    DEFF Research Database (Denmark)

    Abdallah, Basem M; Al-Shammary, Asma; Skagen, Peter

    2015-01-01

    Bone marrow stromal cells (BMSCs, also known as bone marrow-derived mesenchymal stem cells) and their progenitors have been identified based on retrospective functional criteria. CD markers are employed to define cell populations with distinct functional characteristics. However, defining and pro...

  2. CD146/MCAM defines functionality of human bone marrow stromal stem cell populations

    DEFF Research Database (Denmark)

    Harkness, Linda; Zaher, Walid; Ditzel, Nicholas

    2016-01-01

    BACKGROUND: Identification of surface markers for prospective isolation of functionally homogenous populations of human skeletal (stromal, mesenchymal) stem cells (hMSCs) is highly relevant for cell therapy protocols. Thus, we examined the possible use of CD146 to subtype a heterogeneous hMSC...... population. METHODS: Using flow cytometry and cell sorting, we isolated two distinct hMSC-CD146(+) and hMSC-CD146(-) cell populations from the telomerized human bone marrow-derived stromal cell line (hMSC-TERT). Cells were examined for differences in their size, shape and texture by using high...... and adipocytes on the basis of gene expression and protein production of lineage-specific markers. In vivo, hMSC-CD146(+) and hMSC-CD146(-) cells formed bone and bone marrow organ when implanted subcutaneously in immune-deficient mice. Bone was enriched in hMSC-CD146(-) cells (12.6 % versus 8.1 %) and bone...

  3. Defining cell populations with single-cell gene expression profiling: correlations and identification of astrocyte subpopulations

    Czech Academy of Sciences Publication Activity Database

    Stahlberg, A.; Andersson, D.; Aurelius, J.; Faiz, M.; Pekna, M.; Kubista, Mikael; Pekny, M.

    2011-01-01

    Roč. 39, č. 4 (2011) ISSN 0305-1048 R&D Projects: GA AV ČR IAA500970904; GA ČR GAP303/10/1338 Institutional research plan: CEZ:AV0Z50520701 Keywords : EMBRYONIC STEM-CELLS * REAL-TIME PCR * MESSENGER-RNA Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 8.026, year: 2011

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

    Science.gov (United States)

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

    2011-07-01

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

  5. Multilineage Potential and Self-Renewal Define an Epithelial Progenitor Cell Population in the Adult Thymus

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    Kahlia Wong

    2014-08-01

    Full Text Available Thymic epithelial cells (TECs are critical for T cell development and self-tolerance but are gradually lost with age. The existence of thymic epithelial progenitors (TEPCs in the postnatal thymus has been inferred, but their identity has remained enigmatic. Here, we assessed the entire adult TEC compartment in order to reveal progenitor capacity is retained exclusively within a subset of immature thymic epithelium displaying several hallmark features of stem/progenitor function. These adult TEPCs generate mature cortical and medullary lineages in a stepwise fashion, including Aire+ TEC, within fetal thymus reaggregate grafts. Although relatively quiescent in vivo, adult TEPCs demonstrate significant in vitro colony formation and self-renewal. Importantly, 3D-cultured TEPCs retain their capacity to differentiate into cortical and medullary TEC lineages when returned to an in vivo thymic microenvironment. No other postnatal TEC subset exhibits this combination of properties. The characterization of adult TEPC will enable progress in understanding TEC biology in aging and regeneration.

  6. Lateral hypothalamic thyrotropin-releasing hormone neurons: distribution and relationship to histochemically defined cell populations in the rat.

    Science.gov (United States)

    Horjales-Araujo, E; Hellysaz, A; Broberger, C

    2014-09-26

    The lateral hypothalamic area (LHA) constitutes a large component of the hypothalamus, and has been implicated in several aspects of motivated behavior. The LHA is of particular relevance to behavioral state control and the maintenance of arousal. Due to the cellular heterogeneity of this region, however, only some subpopulations of LHA cells have been properly anatomically characterized. Here, we have focused on cells expressing thyrotropin-releasing hormone (TRH), a peptide found in the LHA that has been implicated as a promoter of arousal. Immunofluorescence and in situ hybridization were used to map the LHA TRH population in the rat, and cells were observed to form a large ventral cluster that extended throughout almost the entire rostro-caudal axis of the hypothalamus. Almost no examples of coexistence were seen when sections were double-stained for TRH and markers of other LHA populations, including the peptides hypocretin/orexin, melanin-concentrating hormone and neurotensin. In the juxtaparaventricular area, however, a discrete group of TRH-immunoreactive cells were also stained with antisera against enkephalin and urocortin 3. Innervation from the metabolically sensitive hypothalamic arcuate nucleus was investigated by double-staining for peptide markers of the two centrally projecting groups of arcuate neurons, agouti gene-related peptide and α-melanocyte-stimulating hormone, respectively; both populations of terminals were observed forming close appositions on TRH cells in the LHA. The present study indicates that TRH-expressing cells form a unique population in the LHA that may serve as a link between metabolic signals and the generation of arousal. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.

  7. Non-coordinate expression of J-chain and Blimp-1 define nurse shark plasma cell populations during ontogeny

    Science.gov (United States)

    Castro, Caitlin D.; Ohta, Yuko; Dooley, Helen; Flajnik, Martin F.

    2014-01-01

    Summary Blimp-1 is the master regulator of plasma cell development, controlling genes such as J-chain and secretory Ig heavy chain. However, some mammalian plasma cells do not express J-chain, and mammalian B1 cells secrete “natural” IgM antibodies without upregulating Blimp-1. While these results have been controversial in mammalian systems, here we describe subsets of normally occurring Blimp-1- antibody secreting cells in nurse sharks, found in lymphoid tissues at all ontogenic stages. Sharks naturally produce large amounts of both pentameric (classically ‘19S’) and monomeric (classically ‘7S’) IgM, the latter an indicator of adaptive immunity. Consistent with the mammalian paradigm, shark Blimp-1 is expressed in splenic 7S IgM-secreting cells, though rarely detected in the J-chain+ cells producing 19S IgM. Although IgM transcript levels are lower in J-chain+ cells, these cells nevertheless secrete 19S IgM in the absence of Blimp-1, as demonstrated by ELISPOT and metabolic labeling. Additionally, cells in the shark bone marrow equivalent (epigonal) are Blimp-1-. Our data suggest that, in sharks, 19S-secreting cells and other secreting memory B cells in the epigonal can be maintained for long periods without Blimp-1, but like in mammals, Blimp-1 is required for terminating the B cell program following an adaptive immune response in the spleen. PMID:23897025

  8. Noncoordinate expression of J-chain and Blimp-1 define nurse shark plasma cell populations during ontogeny.

    Science.gov (United States)

    Castro, Caitlin D; Ohta, Yuko; Dooley, Helen; Flajnik, Martin F

    2013-11-01

    B-lymphocyte-induced maturation protein 1 (Blimp-1) is the master regulator of plasma cell development, controlling genes such as those encoding J-chain and secretory Ig heavy chain. However, some mammalian plasma cells do not express J-chain, and mammalian B1 cells secrete "natural" IgM antibodies without upregulating Blimp-1. While these results have been controversial in mammalian systems, here we describe subsets of normally occurring Blimp-1(-) antibody-secreting cells in nurse sharks, found in lymphoid tissues at all ontogenic stages. Sharks naturally produce large amounts of both pentameric (classically "19S") and monomeric (classically "7S") IgM, the latter an indicator of adaptive immunity. Consistent with the mammalian paradigm, shark Blimp-1 is expressed in splenic 7S IgM-secreting cells, though rarely detected in the J-chain(+) cells producing 19S IgM. Although IgM transcript levels are lower in J-chain(+) cells, these cells nevertheless secrete 19S IgM in the absence of Blimp-1, as demonstrated by ELISPOT and metabolic labeling. Additionally, cells in the shark BM equivalent (epigonal) are Blimp-1(-). Our data suggest that, in sharks, 19S-secreting cells and other secreting memory B cells in the epigonal are maintained for long periods without Blimp-1, but like in mammals, Blimp-1 is required for terminating the B-cell program following an adaptive immune response in the spleen. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Identification of markers that functionally define a quiescent multiple myeloma cell sub-population surviving bortezomib treatment

    International Nuclear Information System (INIS)

    Adomako, Alfred; Calvo, Veronica; Biran, Noa; Osman, Keren; Chari, Ajai; Paton, James C; Paton, Adrienne W; Moore, Kateri; Schewe, Denis M; Aguirre-Ghiso, Julio A

    2015-01-01

    The mechanisms allowing residual multiple myeloma (MM) cells to persist after bortezomib (Bz) treatment remain unclear. We hypothesized that studying the biology of bortezomib-surviving cells may reveal markers to identify these cells and survival signals to target and kill residual MM cells. We used H2B-GFP label retention, biochemical tools and in vitro and in vivo experiments to characterize growth arrest and the unfolded protein responses in quiescent Bz-surviving cells. We also tested the effect of a demethylating agent, 5-Azacytidine, on Bz-induced quiescence and whether inhibiting the chaperone GRP78/BiP (henceforth GRP78) with a specific toxin induced apoptosis in Bz-surviving cells. Finally, we used MM patient samples to test whether GRP78 levels might associate with disease progression. Statistical analysis employed t-test and Mann-Whitney tests at a 95% confidence. We report that Bz-surviving MM cells in vitro and in vivo enter quiescence characterized by p21 CIP1 upregulation. Bz-surviving MM cells also downregulated CDK6, Ki67 and P-Rb. H2B-GFP label retention showed that Bz-surviving MM cells are either slow-cycling or deeply quiescent. The Bz-induced quiescence was stabilized by low dose (500nM) of 5-azacytidine (Aza) pre-treatment, which also potentiated the initial Bz-induced apoptosis. We also found that expression of GRP78, an unfolded protein response (UPR) survival factor, persisted in MM quiescent cells. Importantly, GRP78 downregulation using a specific SubAB bacterial toxin killed Bz-surviving MM cells. Finally, quantification of Grp78 high /CD138+ MM cells from patients suggested that high levels correlated with progressive disease. We conclude that Bz-surviving MM cells display a GRP78 HIGH /p21 HIGH /CDK6 LOW /P-Rb LOW profile, and these markers may identify quiescent MM cells capable of fueling recurrences. We further conclude that Aza + Bz treatment of MM may represent a novel strategy to delay recurrences by enhancing Bz

  10. Populism in Lithuania: defining the research tradition

    OpenAIRE

    Aleknonis, Gintaras; Matkevičienė, Renata

    2016-01-01

    The research on populism and populist political communication in Lithuania is rather limited, regardless of the fact that populist movements and politicians are influential on national and local political levels; they also receive sufficient support from a significant share of the population. Because the Western European research tradition is concentrated on the challenges of right-wing populism, Lithuanian political scientists distinguish right-wing populism as more significant in comparison...

  11. Populism in Lithuania: Defining the Research Tradition

    Directory of Open Access Journals (Sweden)

    Aleknonis Gintaras

    2016-06-01

    Full Text Available The research on populism and populist political communication in Lithuania is rather limited, regardless of the fact that populist movements and politicians are influential on national and local political levels; they also receive sufficient support from a significant share of the population. Because the Western European research tradition is concentrated on the challenges of right-wing populism, Lithuanian political scientists distinguish right-wing populism as more significant in comparison to left-wing populism. Although Lithuanian researchers note, that in the balance of the left-right wing populists, Lithuania stands out with the majority of left-wing populists, in comparison to the popularity and number of right-wing populists in neighbouring countries.

  12. Mercury levels in defined Italian population groups

    International Nuclear Information System (INIS)

    Ingrao, G.; Belloni, P.

    1992-01-01

    The consumption of fish and seafood usually is the main source of intake of methylmercury for members of the general population. Therefore subjects having a diet rich in these food items present a high risk of exceeding the tolerable recommended weekly intake of mercury set by FAO and WHO. The average consumption of fish at a national level is rather small in Italy, 12.5 kg per year, consequently the risk of exposure to elevated levels of mercury through the diet for members of the Italian general population is rather negligible. However, fish is one of the main components of the diet of some population groups. These groups are usually found in coastal towns close fishing ports and include subjects working as fishermen, fish dealers, restaurant workers and their families. The purpose of this research programme, carried our with the collaboration of the National Institute of Nutrition is to determine the levels of mercury and methylmercury in hair samples of subjects having a higher than average fish consumption and to evaluate the effects of elevated intakes of mercury. 1 ref., 13 figs

  13. Mercury levels in defined Italian population groups

    International Nuclear Information System (INIS)

    Ingrao, G.; Belloni, P.

    1991-01-01

    Our group conducts its research activity in the Department AMB-BIO (Biological and Sanitary Effect of Toxic Agents) of ENEA (National Committee for Research and Development of Nuclear and Alternative Energy) at the research centre of Casaccia. The food chain is the main pathway leading to humans for most of the trace elements. The research, therefore, has been directed mainly towards the study of the variability of the trace element content in the Italian diet. This programme aims at assessing the adequacy of the essential trace elements ingestion, and to verify that the ingestion of toxic trace elements is below the recommended values. Part of this research was conducted in the frame of the IAEA CRP on ''Human daily Intakes of Nutritionally Important Trace Elements as Measured by Nuclear and Other Techniques''. Studies carried out by the National Institute of Nutrition and FAO have shown that there are some population groups having a fish consumption significantly higher than the average value for the Italian population. These groups are usually found in coastal towns were fishing is one of the main occupation and generally includes fishermen, fish dealers, restaurant workers and their families. A pilot study was conducted in one of these towns, Bagnara Calabra in the South of Italy, where the average fish consumption is 27.1 kg per year, which is more than twice the national average. The results have shown that the mercury concentration in the diet is significantly higher than in other Italian locations, the mercury levels in blood and hair sample in these subjects are also significantly higher than the values reported for subjects of the general Italian population. 6 refs

  14. Research Network of Tehran Defined Population: Methodology and Establishment

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    Ali-Asghar Kolahi

    2015-12-01

    Full Text Available Background: We need a defined population for determining prevalence and incidence of diseases, as well as conducting interventional, cohort and longitudinal studies, calculating correct and timely public health indicators, assessing actual health needs of community, performing educational programs and interventions to promote healthy lifestyle, and enhancing quality of primary health services.The objective of this project was to determine a defined population which is representative of Tehran, the Capital of Iran. This article reports the methodology and establishment of the research network of Tehran defined population.Methods: This project started by selecting two urban health centers from each of the five district health centers affiliated to Shahid Beheshti University of Medical Sciences in 2012. Inside each selected urban health center, one defined population research station was established. Two new centers have been added during 2013 and 2014. For the time being, the number of the covered population of the network has reached 40000 individuals. The most important criterion for the defined population has been to be representative of the population of Tehran. For this, we selected two urban health centers from 12 of 22 municipality districts and from each of the five different socioeconomic of Greater Tehran. Merely 80000 individuals in neighborhoods of each defined population research station were considered as control group of the project.Findings: Totally we selected 12 defined population research stations and their under-covered population developed a defined population which is representative of Tehran population.Conclusion: a population lab is ready now in metropolitan of Tehran.

  15. 40 CFR 68.30 - Defining offsite impacts-population.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 15 2010-07-01 2010-07-01 false Defining offsite impacts-population. 68.30 Section 68.30 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... impacts—population. (a) The owner or operator shall estimate in the RMP the population within a circle...

  16. Tissue microenvironments in the nasal epithelium of rainbow trout (Oncorhynchus mykiss) define two distinct CD8α+ cell populations and establish regional immunity

    Science.gov (United States)

    Sepahi, Ali; Casadei, Elisa; Tacchi, Luca; Muñoz, Pilar; LaPatra, Scott E.; Salinas, Irene

    2016-01-01

    Mucosal surfaces require balancing different physiological roles and immune functions. In order to effectively achieve multifunctionality, mucosal epithelia have evolved unique microenvironments that create unique regional immune responses without impairing other normal physiological functions. Whereas examples of regional immunity are known in other mucosal epithelia, to date, no immune microenvironments have been described in the nasal mucosa, a site where the complex functions of olfaction and immunity need to be orchestrated. In this study we identified for the first time the presence of CD8α+ cells in the rainbow trout (Oncorhynchus mykiss) nasal epithelium. Nasal CD8α+ cells display a distinct phenotype suggestive of CD8+ T cells with high integrin β2 expression. Importantly, nasal CD8α+ cells are located in clusters at the mucosal tip of each olfactory lamella but scattered in the neuroepithelial region. The grouping of CD8α+ cells may be explained by the greater expression of CCL19, ICAM-1, and VCAM-1 in the mucosal tip compared to the neuroepithelium. Whilst viral antigen uptake occurred via both tip and lateral routes, tip resident MHC-II+ cells are located significantly closer to the lumen of the nasal cavity than their neuroepithelial counterparts, therefore having quicker access to invading pathogens. Our studies reveal for the first time compartmentalized mucosal immune responses within the nasal mucosa of a vertebrate species, a strategy that likely optimizes local immune responses while protecting olfactory sensory functions. PMID:27798156

  17. Functional differences between neurochemically defined populations of inhibitory interneurons in the rat spinal dorsal horn ?

    OpenAIRE

    Polg?r, Erika; Sardella, Thomas C.P.; Tiong, Sheena Y.X.; Locke, Samantha; Watanabe, Masahiko; Todd, Andrew J.

    2013-01-01

    In order to understand how nociceptive information is processed in the spinal dorsal horn we need to unravel the complex synaptic circuits involving interneurons, which constitute the vast majority of the neurons in laminae I?III. The main limitation has been the difficulty in defining functional populations among these cells. We have recently identified 4 non-overlapping classes of inhibitory interneuron, defined by expression of galanin, neuropeptide Y (NPY), neuronal nitric oxide synthase ...

  18. Using Bayesian Population Viability Analysis to Define Relevant Conservation Objectives.

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    Adam W Green

    Full Text Available Adaptive management provides a useful framework for managing natural resources in the face of uncertainty. An important component of adaptive management is identifying clear, measurable conservation objectives that reflect the desired outcomes of stakeholders. A common objective is to have a sustainable population, or metapopulation, but it can be difficult to quantify a threshold above which such a population is likely to persist. We performed a Bayesian metapopulation viability analysis (BMPVA using a dynamic occupancy model to quantify the characteristics of two wood frog (Lithobates sylvatica metapopulations resulting in sustainable populations, and we demonstrate how the results could be used to define meaningful objectives that serve as the basis of adaptive management. We explored scenarios involving metapopulations with different numbers of patches (pools using estimates of breeding occurrence and successful metamorphosis from two study areas to estimate the probability of quasi-extinction and calculate the proportion of vernal pools producing metamorphs. Our results suggest that ≥50 pools are required to ensure long-term persistence with approximately 16% of pools producing metamorphs in stable metapopulations. We demonstrate one way to incorporate the BMPVA results into a utility function that balances the trade-offs between ecological and financial objectives, which can be used in an adaptive management framework to make optimal, transparent decisions. Our approach provides a framework for using a standard method (i.e., PVA and available information to inform a formal decision process to determine optimal and timely management policies.

  19. Defining Lipid Transport Pathways in Animal Cells

    Science.gov (United States)

    Pagano, Richard E.; Sleight, Richard G.

    1985-09-01

    A new technique for studying the metabolism and intracellular transport of lipid molecules in living cells based on the use of fluorescent lipid analogs is described. The cellular processing of various intermediates (phosphatidic acid and ceramide) and end products (phosphatidylcholine and phosphatidylethanolamine) in lipid biosynthesis is reviewed and a working model for compartmentalization during lipid biosynthesis is presented.

  20. Defined bacterial populations in the rumens of gnotobiotic lambs.

    Science.gov (United States)

    Lysons, R J; Alexander, T J; Wellstead, P D; Hobson, P N; Mann, S O; Stewart, C S

    1976-06-01

    Five gnotobiotic lambs were fed on sterile diets until they were killed at 13 to 21 weeks of age. They were dosed orally with different combinations of 11 species of rumen bacteria. The biochemical reactions of each of the bacteria inoculated had been determined in pure culture in vitro, and they were chosen to perform the main reactions known to be associated with digestion in the normal mature rumen. Two of the bacteria could not be reisolated, but the remainder had established readily in the rumen, forming stable, mixed, defined populations. The total numbers of bacteria in the rumen, and the viable counts of most of the individual species were comparable to those of normal sheep. The concentration of volatile fatty acids was lower, however, and in four of the lambs there was a higher proportion of butyric acid and a lower proportion of propionic acid than in normal sheep. Cellulolytic, ureolytic, and methanogenic activities appeared to be taking place and lactate-utilizing bacteria appeared to reverse the accumulation of lactate which resulted from the activity of lactate-producing bacteria. Some of the bacteria also established at high levels in the caecum.

  1. The Spectrum of Paraneoplastic Cutaneous Vasculitis in a Defined Population

    Science.gov (United States)

    Loricera, Javier; Calvo-Río, Vanesa; Ortiz-Sanjuán, Francisco; González-López, Marcos A.; Fernández-Llaca, Hector; Rueda-Gotor, Javier; Gonzalez-Vela, Maria C.; Alvarez, Lino; Mata, Cristina; González-Lamuño, Domingo; Martínez-Taboada, Victor M.; González-Gay, Miguel A.; Blanco, Ricardo

    2013-01-01

    Abstract Cutaneous vasculitis may be associated with malignancies, and may behave as a paraneoplastic syndrome. This association has been reported in a variable proportion of patients depending on population selection. We conducted the current study to assess the frequency, clinical features, treatment, and outcome of paraneoplastic vasculitis in a large unselected series of 766 patients with cutaneous vasculitis diagnosed at a single university hospital. Sixteen patients (10 men and 6 women; mean age ± standard deviation, 67.94 ± 14.20 yr; range, 40–85 yr) presenting with cutaneous vasculitis were ultimately diagnosed as having an underlying malignancy. They constituted 3.80% of the 421 adult patients. There were 9 hematologic and 7 solid underlying malignancies. Skin lesions were the initial clinical presentation in all of them, and the median interval from the onset of cutaneous vasculitis to the diagnosis of the malignancy was 17 days (range, 8–50 d). The most frequent skin lesions were palpable purpura (15 patients). Other clinical manifestations included constitutional syndrome (10 patients) and arthralgia and/or arthritis (4 cases). Hematologic cytopenias (11 cases) as well as immature peripheral blood cells (6 cases) were frequently observed in the full blood cell count, especially in those with vasculitis associated with hematologic malignancies. Specific treatment for vasculitis was prescribed in 10 patients; nonsteroidal antiinflammatory drugs (4 patients), corticosteroids (3 patients), chloroquine (1 patient), antihistamines (1 patient), and cyclophosphamide (1 patient). Ten patients died due to the malignancy and 6 patients recovered following malignancy therapy. Patients with paraneoplastic vasculitis were older, more frequently had constitutional syndrome, and less frequently had organ damage due to the vasculitis than the remaining patients with cutaneous vasculitis. In summary, cutaneous paraneoplastic vasculitis is an entity not uncommonly

  2. Identity and Diversity of Human Peripheral Th and T Regulatory Cells Defined by Single-Cell Mass Cytometry.

    Science.gov (United States)

    Kunicki, Matthew A; Amaya Hernandez, Laura C; Davis, Kara L; Bacchetta, Rosa; Roncarolo, Maria-Grazia

    2018-01-01

    Human CD3 + CD4 + Th cells, FOXP3 + T regulatory (Treg) cells, and T regulatory type 1 (Tr1) cells are essential for ensuring peripheral immune response and tolerance, but the diversity of Th, Treg, and Tr1 cell subsets has not been fully characterized. Independent functional characterization of human Th1, Th2, Th17, T follicular helper (Tfh), Treg, and Tr1 cells has helped to define unique surface molecules, transcription factors, and signaling profiles for each subset. However, the adequacy of these markers to recapitulate the whole CD3 + CD4 + T cell compartment remains questionable. In this study, we examined CD3 + CD4 + T cell populations by single-cell mass cytometry. We characterize the CD3 + CD4 + Th, Treg, and Tr1 cell populations simultaneously across 23 memory T cell-associated surface and intracellular molecules. High-dimensional analysis identified several new subsets, in addition to the already defined CD3 + CD4 + Th, Treg, and Tr1 cell populations, for a total of 11 Th cell, 4 Treg, and 1 Tr1 cell subsets. Some of these subsets share markers previously thought to be selective for Treg, Th1, Th2, Th17, and Tfh cells, including CD194 (CCR4) + FOXP3 + Treg and CD183 (CXCR3) + T-bet + Th17 cell subsets. Unsupervised clustering displayed a phenotypic organization of CD3 + CD4 + T cells that confirmed their diversity but showed interrelation between the different subsets, including similarity between Th1-Th2-Tfh cell populations and Th17 cells, as well as similarity of Th2 cells with Treg cells. In conclusion, the use of single-cell mass cytometry provides a systems-level characterization of CD3 + CD4 + T cells in healthy human blood, which represents an important baseline reference to investigate abnormalities of different subsets in immune-mediated pathologies. Copyright © 2017 by The American Association of Immunologists, Inc.

  3. Heterogeneity of neuroblastoma cell identity defined by transcriptional circuitries.

    Science.gov (United States)

    Boeva, Valentina; Louis-Brennetot, Caroline; Peltier, Agathe; Durand, Simon; Pierre-Eugène, Cécile; Raynal, Virginie; Etchevers, Heather C; Thomas, Sophie; Lermine, Alban; Daudigeos-Dubus, Estelle; Geoerger, Birgit; Orth, Martin F; Grünewald, Thomas G P; Diaz, Elise; Ducos, Bertrand; Surdez, Didier; Carcaboso, Angel M; Medvedeva, Irina; Deller, Thomas; Combaret, Valérie; Lapouble, Eve; Pierron, Gaelle; Grossetête-Lalami, Sandrine; Baulande, Sylvain; Schleiermacher, Gudrun; Barillot, Emmanuel; Rohrer, Hermann; Delattre, Olivier; Janoueix-Lerosey, Isabelle

    2017-09-01

    Neuroblastoma is a tumor of the peripheral sympathetic nervous system, derived from multipotent neural crest cells (NCCs). To define core regulatory circuitries (CRCs) controlling the gene expression program of neuroblastoma, we established and analyzed the neuroblastoma super-enhancer landscape. We discovered three types of identity in neuroblastoma cell lines: a sympathetic noradrenergic identity, defined by a CRC module including the PHOX2B, HAND2 and GATA3 transcription factors (TFs); an NCC-like identity, driven by a CRC module containing AP-1 TFs; and a mixed type, further deconvoluted at the single-cell level. Treatment of the mixed type with chemotherapeutic agents resulted in enrichment of NCC-like cells. The noradrenergic module was validated by ChIP-seq. Functional studies demonstrated dependency of neuroblastoma with noradrenergic identity on PHOX2B, evocative of lineage addiction. Most neuroblastoma primary tumors express TFs from the noradrenergic and NCC-like modules. Our data demonstrate a previously unknown aspect of tumor heterogeneity relevant for neuroblastoma treatment strategies.

  4. Chapter 22. Cell population kinetics

    International Nuclear Information System (INIS)

    Tubiana, M.

    1975-01-01

    The main contribution of radioisotopes to the development of a new discipline, cell population kinetics, was shown. The aim of this science is to establish, for each tissue of the organism, the life span of its component cells and the mechanisms governing its growth, its differentiation and its homeostasis with respect to outside attacks. Labelling techniques have been used to follow the cells during these various processes. The case of non-dividing cells was considered first, taking as example, the red blood cells of which the lifetime was studied, after which the case of proliferating cells was examined using 14 C- or tritium-labelled thymidine. The methods used to measure the cell cycle parameters were described: labelled-mitosis curve method, double-labelling and continuous labelling methods, proliferation coefficient measurement. Cell kinetics were shown to allow an interpretation of radiobiological data. Finally the practical value of cell kinetics research was shown [fr

  5. Leader Cells Define Directionality of Trunk, but Not Cranial, Neural Crest Cell Migration

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    Jo Richardson

    2016-05-01

    Full Text Available Collective cell migration is fundamental for life and a hallmark of cancer. Neural crest (NC cells migrate collectively, but the mechanisms governing this process remain controversial. Previous analyses in Xenopus indicate that cranial NC (CNC cells are a homogeneous population relying on cell-cell interactions for directional migration, while chick embryo analyses suggest a heterogeneous population with leader cells instructing directionality. Our data in chick and zebrafish embryos show that CNC cells do not require leader cells for migration and all cells present similar migratory capacities. In contrast, laser ablation of trunk NC (TNC cells shows that leader cells direct movement and cell-cell contacts are required for migration. Moreover, leader and follower identities are acquired before the initiation of migration and remain fixed thereafter. Thus, two distinct mechanisms establish the directionality of CNC cells and TNC cells. This implies the existence of multiple molecular mechanisms for collective cell migration.

  6. PKH26 staining defines distinct subsets of normal human colon epithelial cells at different maturation stages.

    Directory of Open Access Journals (Sweden)

    Anna Pastò

    Full Text Available BACKGROUND AND AIM: Colon crypts are characterized by a hierarchy of cells distributed along the crypt axis. Aim of this paper was to develop an in vitro system for separation of epithelial cell subsets in different maturation stages from normal human colon. METHODOLOGY AND MAJOR FINDINGS: Dissociated colonic epithelial cells were stained with PKH26, which allows identification of distinct populations based on their proliferation rate, and cultured in vitro in the absence of serum. The cytofluorimetric expression of CK20, Msi-1 and Lgr5 was studied. The mRNA levels of several stemness-associated genes were also compared in cultured cell populations and in three colon crypt populations isolated by microdissection. A PKH(pos population survived in culture and formed spheroids; this population included subsets with slow (PKH(high and rapid (PKH(low replicative rates. Molecular analysis revealed higher mRNA levels of both Msi-1 and Lgr-5 in PKH(high cells; by cytofluorimetric analysis, Msi-1(+/Lgr5(+ cells were only found within PKH(high cells, whereas Msi-1(+/Lgr5(- cells were also observed in the PKH(low population. As judged by qRT-PCR analysis, the expression of several stemness-associated markers (Bmi-1, EphB2, EpCAM, ALDH1 was highly enriched in Msi-1(+/Lgr5(+ cells. While CK20 expression was mainly found in PKH(low and PKH(neg cells, a small PKH(high subset co-expressed both CK20 and Msi-1, but not Lgr5; cells with these properties also expressed Mucin, and could be identified in vivo in colon crypts. These results mirrored those found in cells isolated from different crypt portions by microdissection, and based on proliferation rates and marker expression they allowed to define several subsets at different maturation stages: PKH(high/Lgr5(+/Msi-1(+/CK20(-, PKH(high/Lgr5(-/Msi-1(+/CK20(+, PKH(low/Lgr5(-/Msi-1(+/Ck20(-, and PKH(low/Lgr5(-/Msi-1(-/CK20(+ cells. CONCLUSIONS: Our data show the possibility of deriving in vitro, without any

  7. NKp46 defines ovine cells that have characteristics corresponding to NK cells

    Directory of Open Access Journals (Sweden)

    Connelley Timothy

    2011-02-01

    Full Text Available Abstract Natural killer (NK cells are well recognized as playing a key role in innate immune defence through cytokine production and cytotoxic activity; additionally recent studies have identified several novel NK cell functions. The ability to study NK cells in the sheep has been restricted due to a lack of specific reagents. We report the generation of a monoclonal antibody specific for ovine NKp46, a receptor which in a number of mammals is expressed exclusively in NK cells. Ovine NKp46+ cells represent a population that is distinct from CD4+ and γδ+ T-cells, B-cells and cells of the monocytic lineage. The NKp46+ cells are heterogenous with respect to expression of CD2 and CD8 and most, but not all, express CD16 - characteristics consistent with NK cell populations in other species. We demonstrate that in addition to populations in peripheral blood and secondary lymphoid organs, ovine NKp46+ populations are also situated at the mucosal surfaces of the lung, gastro-intestinal tract and non-gravid uterus. Furthermore, we show that purified ovine NKp46+ populations cultured in IL-2 and IL-15 have cytotoxic activity that could be enhanced by ligation of NKp46 in re-directed lysis assays. Therefore we conclude that ovine NKp46+ cells represent a population that by phenotype, tissue distribution and function correspond to NK cells and that NKp46 is an activating receptor in sheep as in other species.

  8. Demographic monitoring of wild muriqui populations: Criteria for defining priority areas and monitoring intensity.

    Science.gov (United States)

    Strier, Karen B; Possamai, Carla B; Tabacow, Fernanda P; Pissinatti, Alcides; Lanna, Andre M; Rodrigues de Melo, Fabiano; Moreira, Leandro; Talebi, Maurício; Breves, Paula; Mendes, Sérgio L; Jerusalinsky, Leandro

    2017-01-01

    Demographic data are essential to assessments of the status of endangered species. However, establishing an integrated monitoring program to obtain useful data on contemporary and future population trends requires both the identification of priority areas and populations and realistic evaluations of the kinds of data that can be obtained under different monitoring regimes. We analyzed all known populations of a critically endangered primate, the muriqui (genus: Brachyteles) using population size, genetic uniqueness, geographic importance (including potential importance in corridor programs) and implementability scores to define monitoring priorities. Our analyses revealed nine priority populations for the northern muriqui (B. hypoxanthus) and nine for the southern muriqui (B. arachnoides). In addition, we employed knowledge of muriqui developmental and life history characteristics to define the minimum monitoring intensity needed to evaluate demographic trends along a continuum ranging from simple descriptive changes in population size to predictions of population changes derived from individual based life histories. Our study, stimulated by the Brazilian government's National Action Plan for the Conservation of Muriquis, is fundamental to meeting the conservation goals for this genus, and also provides a model for defining priorities and methods for the implementation of integrated demographic monitoring programs for other endangered and critically endangered species of primates.

  9. Demographic monitoring of wild muriqui populations: Criteria for defining priority areas and monitoring intensity.

    Directory of Open Access Journals (Sweden)

    Karen B Strier

    Full Text Available Demographic data are essential to assessments of the status of endangered species. However, establishing an integrated monitoring program to obtain useful data on contemporary and future population trends requires both the identification of priority areas and populations and realistic evaluations of the kinds of data that can be obtained under different monitoring regimes. We analyzed all known populations of a critically endangered primate, the muriqui (genus: Brachyteles using population size, genetic uniqueness, geographic importance (including potential importance in corridor programs and implementability scores to define monitoring priorities. Our analyses revealed nine priority populations for the northern muriqui (B. hypoxanthus and nine for the southern muriqui (B. arachnoides. In addition, we employed knowledge of muriqui developmental and life history characteristics to define the minimum monitoring intensity needed to evaluate demographic trends along a continuum ranging from simple descriptive changes in population size to predictions of population changes derived from individual based life histories. Our study, stimulated by the Brazilian government's National Action Plan for the Conservation of Muriquis, is fundamental to meeting the conservation goals for this genus, and also provides a model for defining priorities and methods for the implementation of integrated demographic monitoring programs for other endangered and critically endangered species of primates.

  10. Plasma Cell Ontogeny Defined by Quantitative Changes in Blimp-1 Expression

    Science.gov (United States)

    Kallies, Axel; Hasbold, Jhagvaral; Tarlinton, David M.; Dietrich, Wendy; Corcoran, Lynn M.; Hodgkin, Philip D.; Nutt, Stephen L.

    2004-01-01

    Plasma cells comprise a population of terminally differentiated B cells that are dependent on the transcriptional regulator B lymphocyte–induced maturation protein 1 (Blimp-1) for their development. We have introduced a gfp reporter into the Blimp-1 locus and shown that heterozygous mice express the green fluorescent protein in all antibody-secreting cells (ASCs) in vivo and in vitro. In vitro, these cells display considerable heterogeneity in surface phenotype, immunoglobulin secretion rate, and Blimp-1 expression levels. Importantly, analysis of in vivo ASCs induced by immunization reveals a developmental pathway in which increasing levels of Blimp-1 expression define developmental stages of plasma cell differentiation that have many phenotypic and molecular correlates. Thus, maturation from transient plasmablast to long-lived ASCs in bone marrow is predicated on quantitative increases in Blimp-1 expression. PMID:15492122

  11. Clinical prediction in defined populations: a simulation study investigating when and how to aggregate existing models

    Directory of Open Access Journals (Sweden)

    Glen P. Martin

    2017-01-01

    Full Text Available Abstract Background Clinical prediction models (CPMs are increasingly deployed to support healthcare decisions but they are derived inconsistently, in part due to limited data. An emerging alternative is to aggregate existing CPMs developed for similar settings and outcomes. This simulation study aimed to investigate the impact of between-population-heterogeneity and sample size on aggregating existing CPMs in a defined population, compared with developing a model de novo. Methods Simulations were designed to mimic a scenario in which multiple CPMs for a binary outcome had been derived in distinct, heterogeneous populations, with potentially different predictors available in each. We then generated a new ‘local’ population and compared the performance of CPMs developed for this population by aggregation, using stacked regression, principal component analysis or partial least squares, with redevelopment from scratch using backwards selection and penalised regression. Results While redevelopment approaches resulted in models that were miscalibrated for local datasets of less than 500 observations, model aggregation methods were well calibrated across all simulation scenarios. When the size of local data was less than 1000 observations and between-population-heterogeneity was small, aggregating existing CPMs gave better discrimination and had the lowest mean square error in the predicted risks compared with deriving a new model. Conversely, given greater than 1000 observations and significant between-population-heterogeneity, then redevelopment outperformed the aggregation approaches. In all other scenarios, both aggregation and de novo derivation resulted in similar predictive performance. Conclusion This study demonstrates a pragmatic approach to contextualising CPMs to defined populations. When aiming to develop models in defined populations, modellers should consider existing CPMs, with aggregation approaches being a suitable modelling

  12. Population dynamics in vasopressin cells.

    Science.gov (United States)

    Leng, Gareth; Brown, Colin; Sabatier, Nancy; Scott, Victoria

    2008-01-01

    Most neurons sense and code change, and when presented with a constant stimulus they adapt, so as to be able to detect a fresh change. However, for some things it is important to know their absolute level; to encode such information, neurons must sustain their response to an unchanging stimulus while remaining able to respond to a change in that stimulus. One system that encodes the absolute level of a stimulus is the vasopressin system, which generates a hormonal signal that is proportional to plasma osmolality. Vasopressin cells sense plasma osmolality and secrete appropriate levels of vasopressin from the neurohypophysis as needed to control water excretion; this requires sustained secretion under basal conditions and the ability to increase (or decrease) secretion should plasma osmolality change. Here we explore the mechanisms that enable vasopressin cells to fulfill this function, and consider how coordination between the cells might distribute the secretory load across the population of vasopressin cells. 2008 S. Karger AG, Basel.

  13. DEFINING RECOVERY GOALS AND STRATEGIES FOR ENDANGERED SPECIES USING SPATIALLY-EXPLICIT POPULATION MODELS

    Science.gov (United States)

    We used a spatially explicit population model of wolves (Canis lupus) to propose a framework for defining rangewide recovery priorities and finer-scale strategies for regional reintroductions. The model predicts that Yellowstone and central Idaho, where wolves have recently been ...

  14. Defining human mesenchymal stem cell efficacy in vivo

    Directory of Open Access Journals (Sweden)

    Lennon Donald P

    2010-10-01

    Full Text Available Abstract Allogeneic human mesenchymal stem cells (hMSCs can suppress graft versus host disease (GvHD and have profound anti-inflammatory and regenerative capacity in stroke, infarct, spinal cord injury, meniscus regeneration, tendinitis, acute renal failure, and heart disease in human and animal models of disease. There is significant clinical hMSC variability in efficacy and the ultimate response in vivo. The challenge in hMSC based therapy is defining the efficacy of hMSC in vivo. Models which may provide insight into hMSC bioactivity in vivo would provide a means to distinguish hMSCs for clinical utility. hMSC function has been described as both regenerative and trophic through the production of bioactive factors. The regenerative component involves the multi-potentiality of hMSC progenitor differentiation. The secreted factors generated by the hMSCs are milieu and injury specific providing unique niches for responses in vivo. These bioactive factors are anti-scarring, angiogenic, anti-apoptotic as well as regenerative. Further, from an immunological standpoint, hMSC's can avoid host immune response, providing xenographic applications. To study the in vivo immuno-regulatory effectiveness of hMSCs, we used the ovalbumin challenge model of acute asthma. This is a quick 3 week in vivo pulmonary inflammation model with readily accessible ways of measuring effectiveness of hMSCs. Our data show that there is a direct correlation between the traditional ceramic cube score to hMSCs attenuation of cellular recruitment due to ovalbumin challenge. The results from these studies verify the in vivo immuno-modulator effectiveness of hMSCs and support the potential use of the ovalbumin model as an in vivo model of hMSC potency and efficacy. Our data also support future directions toward exploring hMSCs as an alternative therapeutic for the treatment of airway inflammation associated with asthma.

  15. A chemically defined substrate for the expansion and neuronal differentiation of human pluripotent stem cell-derived neural progenitor cells

    Directory of Open Access Journals (Sweden)

    Yihuan Tsai

    2015-07-01

    Full Text Available Due to the limitation of current pharmacological therapeutic strategies, stem cell therapies have emerged as a viable option for treating many incurable neurological disorders. Specifically, human pluripotent stem cell (hPSC-derived neural progenitor cells (hNPCs, a multipotent cell population that is capable of near indefinite expansion and subsequent differentiation into the various cell types that comprise the central nervous system (CNS, could provide an unlimited source of cells for such cell-based therapies. However the clinical application of these cells will require (i defined, xeno-free conditions for their expansion and neuronal differentiation and (ii scalable culture systems that enable their expansion and neuronal differentiation in numbers sufficient for regenerative medicine and drug screening purposes. Current extracellular matrix protein (ECMP-based substrates for the culture of hNPCs are expensive, difficult to isolate, subject to batch-to-batch variations, and, therefore, unsuitable for clinical application of hNPCs. Using a high-throughput array-based screening approach, we identified a synthetic polymer, poly(4-vinyl phenol (P4VP, that supported the long-term proliferation and self-renewal of hNPCs. The hNPCs cultured on P4VP maintained their characteristic morphology, expressed high levels of markers of multipotency, and retained their ability to differentiate into neurons. Such chemically defined substrates will eliminate critical roadblocks for the utilization of hNPCs for human neural regenerative repair, disease modeling, and drug discovery.

  16. Population Health Research: Early Description of the Organizational Shift Toward Population Health Management and Defining a Vision for Leadership.

    Science.gov (United States)

    Caldararo, Kristi L; Nash, David B

    2017-10-01

    As health care delivery systems adapt to the changing marketplace, many struggle to define a clear strategy that will prove successful in managing the health of entire populations. The federal government continues to put increasing pressure on organizations to shift away from the traditional way of delivering episodic care and move toward managing populations as a whole-before, during, and after a patient presents in a health care facility. Private payers have begun to follow suit as risk-based payer contracts and bundled payment models become increasingly popular. For organizations to adequately influence the health outcomes of a population, they must be responsible for more than just a patient's medical care. They must partner with the community to create a strategy that encompasses the psychosocial and environmental factors that contribute to one's health. Although health care leaders know this industry transformation is imminent, there is minimal research that shares best practices in regard to designing and implementing a successful population health management strategy. Interviews were conducted with leadership from 10 organizations in order to understand the strategic approach taken by delivery systems and health care institutions that view population health as a key aspect of their overall mission. Responses were recorded and outlined in a detailed response grid. The objective is to provide a qualitative overview of how industry leaders are currently responding to population health. Additionally, common themes and recommendations are presented to serve as guidance for other health care organizations that are at the start of their journey toward population health management.

  17. Recombinant human albumin supports single cell cloning of CHO cells in chemically defined media.

    Science.gov (United States)

    Zhu, Jiang; Wooh, Jong Wei; Hou, Jeff Jia Cheng; Hughes, Benjamin S; Gray, Peter P; Munro, Trent P

    2012-01-01

    Biologic drugs, such as monoclonal antibodies, are commonly made using mammalian cells in culture. The cell lines used for manufacturing should ideally be clonal, meaning derived from a single cell, which represents a technically challenging process. Fetal bovine serum is often used to support low cell density cultures, however, from a regulatory perspective, it is preferable to avoid animal-derived components to increase process consistency and reduce the risk of contamination from adventitious agents. Chinese hamster ovary (CHO) cells are the most widely used cell line in industry and a large number of serum-free, protein-free, and fully chemically defined growth media are commercially available, although these media alone do not readily support efficient single cell cloning. In this work, we have developed a simple, fully defined, single-cell cloning media, specifically for CHO cells, using commercially available reagents. Our results show that a 1:1 mixture of CD-CHO™ and DMEM/F12 supplemented with 1.5 g/L of recombinant albumin (Albucult®) supports single cell cloning. This formulation can support recovery of single cells in 43% of cultures compared to 62% in the presence of serum. Copyright © 2012 American Institute of Chemical Engineers (AIChE).

  18. Ovarian cancer stem cells are enriched in side population and aldehyde dehydrogenase bright overlapping population.

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    Kazuyo Yasuda

    Full Text Available Cancer stem-like cells (CSCs/cancer-initiaiting cells (CICs are defined as a small population of cancer cells that have self-renewal capacity, differentiation potential and high tumor-initiating ability. CSCs/CICs of ovarian cancer have been isolated by side population (SP analysis, ALDEFLUOR assay and using cell surface markers. However, these approaches are not definitive markers for CSCs/CICs, and it is necessary to refine recent methods for identifying more highly purified CSCs/CICs. In this study, we analyzed SP cells and aldehyde dehydrogenese bright (ALDH(Br cells from ovarian cancer cells. Both SP cells and ALDH(Br cells exhibited higher tumor-initiating ability and higher expression level of a stem cell marker, sex determining region Y-box 2 (SOX2, than those of main population (MP cells and ALDH(Low cells, respectively. We analyzed an SP and ALDH(Br overlapping population (SP/ALDH(Br, and the SP/ALDH(Br population exhibited higher tumor-initiating ability than that of SP cells or ALDH(Br cells, enabling initiation of tumor with as few as 10(2 cells. Furthermore, SP/ADLH(Br population showed higher sphere-forming ability, cisplatin resistance, adipocyte differentiation ability and expression of SOX2 than those of SP/ALDH(Low, MP/ALDH(Br and MP/ALDH(Low cells. Gene knockdown of SOX2 suppressed the tumor-initiation of ovarian cancer cells. An SP/ALDH(Br population was detected in several gynecological cancer cells with ratios of 0.1% for HEC-1 endometrioid adenocarcinoma cells to 1% for MCAS ovary mucinous adenocarcinoma cells. Taken together, use of the SP and ALDH(Br overlapping population is a promising approach to isolate highly purified CSCs/CICs and SOX2 might be a novel functional marker for ovarian CSCs/CICs.

  19. Automation of 3D cell culture using chemically defined hydrogels.

    Science.gov (United States)

    Rimann, Markus; Angres, Brigitte; Patocchi-Tenzer, Isabel; Braum, Susanne; Graf-Hausner, Ursula

    2014-04-01

    Drug development relies on high-throughput screening involving cell-based assays. Most of the assays are still based on cells grown in monolayer rather than in three-dimensional (3D) formats, although cells behave more in vivo-like in 3D. To exemplify the adoption of 3D techniques in drug development, this project investigated the automation of a hydrogel-based 3D cell culture system using a liquid-handling robot. The hydrogel technology used offers high flexibility of gel design due to a modular composition of a polymer network and bioactive components. The cell inert degradation of the gel at the end of the culture period guaranteed the harmless isolation of live cells for further downstream processing. Human colon carcinoma cells HCT-116 were encapsulated and grown in these dextran-based hydrogels, thereby forming 3D multicellular spheroids. Viability and DNA content of the cells were shown to be similar in automated and manually produced hydrogels. Furthermore, cell treatment with toxic Taxol concentrations (100 nM) had the same effect on HCT-116 cell viability in manually and automated hydrogel preparations. Finally, a fully automated dose-response curve with the reference compound Taxol showed the potential of this hydrogel-based 3D cell culture system in advanced drug development.

  20. Primate-specific endogenous retrovirus-driven transcription defines naive-like stem cells.

    Science.gov (United States)

    Wang, Jichang; Xie, Gangcai; Singh, Manvendra; Ghanbarian, Avazeh T; Raskó, Tamás; Szvetnik, Attila; Cai, Huiqiang; Besser, Daniel; Prigione, Alessandro; Fuchs, Nina V; Schumann, Gerald G; Chen, Wei; Lorincz, Matthew C; Ivics, Zoltán; Hurst, Laurence D; Izsvák, Zsuzsanna

    2014-12-18

    Naive embryonic stem cells hold great promise for research and therapeutics as they have broad and robust developmental potential. While such cells are readily derived from mouse blastocysts it has not been possible to isolate human equivalents easily, although human naive-like cells have been artificially generated (rather than extracted) by coercion of human primed embryonic stem cells by modifying culture conditions or through transgenic modification. Here we show that a sub-population within cultures of human embryonic stem cells (hESCs) and induced pluripotent stem cells (hiPSCs) manifests key properties of naive state cells. These naive-like cells can be genetically tagged, and are associated with elevated transcription of HERVH, a primate-specific endogenous retrovirus. HERVH elements provide functional binding sites for a combination of naive pluripotency transcription factors, including LBP9, recently recognized as relevant to naivety in mice. LBP9-HERVH drives hESC-specific alternative and chimaeric transcripts, including pluripotency-modulating long non-coding RNAs. Disruption of LBP9, HERVH and HERVH-derived transcripts compromises self-renewal. These observations define HERVH expression as a hallmark of naive-like hESCs, and establish novel primate-specific transcriptional circuitry regulating pluripotency.

  1. Induction of cancer stem cell properties in colon cancer cells by defined factors.

    Directory of Open Access Journals (Sweden)

    Nobu Oshima

    Full Text Available Cancer stem cells (CSCs are considered to be responsible for the dismal prognosis of cancer patients. However, little is known about the molecular mechanisms underlying the acquisition and maintenance of CSC properties in cancer cells because of their rarity in clinical samples. We herein induced CSC properties in cancer cells using defined factors. We retrovirally introduced a set of defined factors (OCT3/4, SOX2 and KLF4 into human colon cancer cells, followed by culture with conventional serum-containing medium, not human embryonic stem cell medium. We then evaluated the CSC properties in the cells. The colon cancer cells transduced with the three factors showed significantly enhanced CSC properties in terms of the marker gene expression, sphere formation, chemoresistance and tumorigenicity. We designated the cells with CSC properties induced by the factors, a subset of the transduced cells, as induced CSCs (iCSCs. Moreover, we established a novel technology to isolate and collect the iCSCs based on the differences in the degree of the dye-effluxing activity enhancement. The xenografts derived from our iCSCs were not teratomas. Notably, in contrast to the tumors from the parental cancer cells, the iCSC-based tumors mimicked actual human colon cancer tissues in terms of their immunohistological findings, which showed colonic lineage differentiation. In addition, we confirmed that the phenotypes of our iCSCs were reproducible in serial transplantation experiments. By introducing defined factors, we generated iCSCs with lineage specificity directly from cancer cells, not via an induced pluripotent stem cell state. The novel method enables us to obtain abundant materials of CSCs that not only have enhanced tumorigenicity, but also the ability to differentiate to recapitulate a specific type of cancer tissues. Our method can be of great value to fully understand CSCs and develop new therapies targeting CSCs.

  2. Gene expression heterogeneities in embryonic stem cell populations

    DEFF Research Database (Denmark)

    Martinez Arias, Alfonso; Brickman, Joshua M

    2011-01-01

    Stem and progenitor cells are populations of cells that retain the capacity to populate specific lineages and to transit this capacity through cell division. However, attempts to define markers for stem cells have met with limited success. Here we consider whether this limited success reflects...... an intrinsic requirement for heterogeneity with stem cell populations. We focus on Embryonic Stem (ES) cells, in vitro derived cell lines from the early embryo that are considered both pluripotent (able to generate all the lineages of the future embryo) and indefinitely self renewing. We examine the relevance...... of recently reported heterogeneities in ES cells and whether these heterogeneities themselves are inherent requirements of functional potency and self renewal....

  3. Geriatrics and the triple aim: defining preventable hospitalizations in the long-term care population.

    Science.gov (United States)

    Ouslander, Joseph G; Maslow, Katie

    2012-12-01

    Reducing preventable hospitalizations is fundamental to the "triple aim" of improving care, improving health, and reducing costs. New federal government initiatives that create strong pressure to reduce such hospitalizations are being or will soon be implemented. These initiatives use quality measures to define which hospitalizations are preventable. Reducing hospitalizations could greatly benefit frail and chronically ill adults and older people who receive long-term care (LTC) because they often experience negative effects of hospitalization, including hospital-acquired conditions, morbidity, and loss of functional abilities. Conversely, reducing hospitalizations could mean that some people will not receive hospital care they need, especially if the selected measures do not adequately define hospitalizations that can be prevented without jeopardizing the person's health and safety. An extensive literature search identified 250 measures of preventable hospitalizations, but the measures have not been validated in the LTC population and generally do not account for comorbidity or the capacity of various LTC settings to provide the required care without hospitalization. Additional efforts are needed to develop measures that accurately differentiate preventable from necessary hospitalizations for the LTC population, are transparent and fair to providers, and minimize the potential for gaming and unintended consequences. As the new initiatives take effect, it is critical to monitor their effect and to develop and disseminate training and resources to support the many community- and institution-based healthcare professionals and emergency department staff involved in decisions about hospitalization for this population. © 2012, Copyright the Authors Journal compilation © 2012, The American Geriatrics Society.

  4. Polycystic kidney disease among 4,436 intracranial aneurysm patients from a defined population.

    Science.gov (United States)

    Nurmonen, Heidi J; Huttunen, Terhi; Huttunen, Jukka; Kurki, Mitja I; Helin, Katariina; Koivisto, Timo; von Und Zu Fraunberg, Mikael; Jääskeläinen, Juha E; Lindgren, Antti E

    2017-10-31

    To define the association of autosomal dominant polycystic kidney disease (ADPKD) with the characteristics of aneurysmal subarachnoid hemorrhage (aSAH) and unruptured intracranial aneurysm (IA) disease. We fused data from the Kuopio Intracranial Aneurysm database (n = 4,436 IA patients) and Finnish nationwide registries into a population-based series of 53 IA patients with ADPKD to compare the aneurysm- and patient-specific characteristics of IA disease in ADPKD and in the general IA population, and to identify risks for de novo IA formation. In total, there were 33 patients with ADPKD with aSAH and 20 patients with ADPKD with unruptured IAs. The median size of ruptured IAs in ADPKD was significantly smaller than in the general population (6.00 vs 8.00 mm) and the proportion of small ruptured IAs was significantly higher (31% vs 18%). Median age at aSAH was 42.8 years, 10 years younger than in the general IA population. Multiple IAs were present in 45% of patients with ADPKD compared to 28% in the general IA population. Cumulative risk of de novo IA formation was 1.3% per patient-year (vs 0.2% in the general IA population). Hazard for de novo aneurysm formation was significantly elevated in patients with ADPKD (Cox regression hazard ratio 7.7, 95% confidence interval 2.8-20; p IAs in patients with ADPKD and risk for de novo IAs is higher than in the general Eastern Finnish population. ADPKD should be considered as an indicator for long-term angiographic follow-up in patients with diagnosed IAs. © 2017 American Academy of Neurology.

  5. An improved ivermectin-activated chloride channel receptor for inhibiting electrical activity in defined neuronal populations

    DEFF Research Database (Denmark)

    Lynagh, Timothy Peter; Lynch, Joseph W

    2010-01-01

    The ability to silence the electrical activity of defined neuronal populations in vivo is dramatically advancing our understanding of brain function. This technology may eventually be useful clinically for treating a variety of neuropathological disorders caused by excessive neuronal activity...... conductance, homomeric expression, and human origin may render the F207A/A288G alpha1 glycine receptor an improved silencing receptor for neuroscientific and clinical purposes. As all known highly ivermectin-sensitive GluClRs contain an endogenous glycine residue at the corresponding location, this residue...

  6. Mesenchymal Stem Cells Retain Their Defining Stem Cell Characteristics After Exposure to Ionizing Radiation

    International Nuclear Information System (INIS)

    Nicolay, Nils H.; Sommer, Eva; Lopez, Ramon; Wirkner, Ute; Trinh, Thuy; Sisombath, Sonevisay; Debus, Jürgen; Ho, Anthony D.; Saffrich, Rainer; Huber, Peter E.

    2013-01-01

    Purpose: Mesenchymal stem cells (MSCs) have the ability to migrate to lesion sites and undergo differentiation into functional tissues. Although this function may be important for tissue regeneration after radiation therapy, the influence of ionizing radiation (IR) on cellular survival and the functional aspects of differentiation and stem cell characteristics of MSCs have remained largely unknown. Methods and Materials: Radiation sensitivity of human primary MSCs from healthy volunteers and primary human fibroblast cells was examined, and cellular morphology, cell cycle effects, apoptosis, and differentiation potential after exposure to IR were assessed. Stem cell gene expression patterns after exposure to IR were studied using gene arrays. Results: MSCs were not more radiosensitive than human primary fibroblasts, whereas there were considerable differences regarding radiation sensitivity within individual MSCs. Cellular morphology, cytoskeletal architecture, and cell motility were not markedly altered by IR. Even after high radiation doses up to 10 Gy, MSCs maintained their differentiation potential. Compared to primary fibroblast cells, MSCs did not show an increase in irradiation-induced apoptosis. Gene expression analyses revealed an upregulation of various genes involved in DNA damage response and DNA repair, but expression of established MSC surface markers appeared only marginally influenced by IR. Conclusions: These data suggest that human MSCs are not more radiosensitive than differentiated primary fibroblasts. In addition, upon photon irradiation, MSCs were able to retain their defining stem cell characteristics both on a functional level and regarding stem cell marker expression

  7. New Monoclonal Antibodies to Defined Cell Surface Proteins on Human Pluripotent Stem Cells.

    Science.gov (United States)

    O'Brien, Carmel M; Chy, Hun S; Zhou, Qi; Blumenfeld, Shiri; Lambshead, Jack W; Liu, Xiaodong; Kie, Joshua; Capaldo, Bianca D; Chung, Tung-Liang; Adams, Timothy E; Phan, Tram; Bentley, John D; McKinstry, William J; Oliva, Karen; McMurrick, Paul J; Wang, Yu-Chieh; Rossello, Fernando J; Lindeman, Geoffrey J; Chen, Di; Jarde, Thierry; Clark, Amander T; Abud, Helen E; Visvader, Jane E; Nefzger, Christian M; Polo, Jose M; Loring, Jeanne F; Laslett, Andrew L

    2017-03-01

    The study and application of human pluripotent stem cells (hPSCs) will be enhanced by the availability of well-characterized monoclonal antibodies (mAbs) detecting cell-surface epitopes. Here, we report generation of seven new mAbs that detect cell surface proteins present on live and fixed human ES cells (hESCs) and human iPS cells (hiPSCs), confirming our previous prediction that these proteins were present on the cell surface of hPSCs. The mAbs all show a high correlation with POU5F1 (OCT4) expression and other hPSC surface markers (TRA-160 and SSEA-4) in hPSC cultures and detect rare OCT4 positive cells in differentiated cell cultures. These mAbs are immunoreactive to cell surface protein epitopes on both primed and naive state hPSCs, providing useful research tools to investigate the cellular mechanisms underlying human pluripotency and states of cellular reprogramming. In addition, we report that subsets of the seven new mAbs are also immunoreactive to human bone marrow-derived mesenchymal stem cells (MSCs), normal human breast subsets and both normal and tumorigenic colorectal cell populations. The mAbs reported here should accelerate the investigation of the nature of pluripotency, and enable development of robust cell separation and tracing technologies to enrich or deplete for hPSCs and other human stem and somatic cell types. Stem Cells 2017;35:626-640. © 2016 The Authors Stem Cells published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

  8. Defining process design space for monoclonal antibody cell culture.

    Science.gov (United States)

    Abu-Absi, Susan Fugett; Yang, LiYing; Thompson, Patrick; Jiang, Canping; Kandula, Sunitha; Schilling, Bernhard; Shukla, Abhinav A

    2010-08-15

    The concept of design space has been taking root as a foundation of in-process control strategies for biopharmaceutical manufacturing processes. During mapping of the process design space, the multidimensional combination of operational variables is studied to quantify the impact on process performance in terms of productivity and product quality. An efficient methodology to map the design space for a monoclonal antibody cell culture process is described. A failure modes and effects analysis (FMEA) was used as the basis for the process characterization exercise. This was followed by an integrated study of the inoculum stage of the process which includes progressive shake flask and seed bioreactor steps. The operating conditions for the seed bioreactor were studied in an integrated fashion with the production bioreactor using a two stage design of experiments (DOE) methodology to enable optimization of operating conditions. A two level Resolution IV design was followed by a central composite design (CCD). These experiments enabled identification of the edge of failure and classification of the operational parameters as non-key, key or critical. In addition, the models generated from the data provide further insight into balancing productivity of the cell culture process with product quality considerations. Finally, process and product-related impurity clearance was evaluated by studies linking the upstream process with downstream purification. Production bioreactor parameters that directly influence antibody charge variants and glycosylation in CHO systems were identified.

  9. A chemically defined substrate for the expansion and neuronal differentiation of human pluripotent stem cell-derived neural progenitor cells.

    Science.gov (United States)

    Tsai, Yihuan; Cutts, Josh; Kimura, Azuma; Varun, Divya; Brafman, David A

    2015-07-01

    Due to the limitation of current pharmacological therapeutic strategies, stem cell therapies have emerged as a viable option for treating many incurable neurological disorders. Specifically, human pluripotent stem cell (hPSC)-derived neural progenitor cells (hNPCs), a multipotent cell population that is capable of near indefinite expansion and subsequent differentiation into the various cell types that comprise the central nervous system (CNS), could provide an unlimited source of cells for such cell-based therapies. However the clinical application of these cells will require (i) defined, xeno-free conditions for their expansion and neuronal differentiation and (ii) scalable culture systems that enable their expansion and neuronal differentiation in numbers sufficient for regenerative medicine and drug screening purposes. Current extracellular matrix protein (ECMP)-based substrates for the culture of hNPCs are expensive, difficult to isolate, subject to batch-to-batch variations, and, therefore, unsuitable for clinical application of hNPCs. Using a high-throughput array-based screening approach, we identified a synthetic polymer, poly(4-vinyl phenol) (P4VP), that supported the long-term proliferation and self-renewal of hNPCs. The hNPCs cultured on P4VP maintained their characteristic morphology, expressed high levels of markers of multipotency, and retained their ability to differentiate into neurons. Such chemically defined substrates will eliminate critical roadblocks for the utilization of hNPCs for human neural regenerative repair, disease modeling, and drug discovery. Copyright © 2015. Published by Elsevier B.V.

  10. Urban dogs in rural areas: Human-mediated movement defines dog populations in southern Chile.

    Science.gov (United States)

    Villatoro, Federico J; Sepúlveda, Maximiliano A; Stowhas, Paulina; Silva-Rodríguez, Eduardo A

    2016-12-01

    Management strategies for dog populations and their diseases include reproductive control, euthanasia and vaccination, among others. However, the effectiveness of these strategies can be severely affected by human-mediated dog movement. If immigration is important, then the location of origin of dogs imported by humans will be fundamental to define the spatial scales over which population management and research should apply. In this context, the main objective of our study was to determine the spatial extent of dog demographic processes in rural areas and the proportion of dogs that could be labeled as immigrants at multiple spatial scales. To address our objective we conducted surveys in households located in a rural landscape in southern Chile. Interviews allowed us to obtain information on the demographic characteristics of dogs in these rural settings, human influence on dog mortality and births, the localities of origin of dogs living in rural areas, and the spatial extent of human-mediated dog movement. We found that most rural dogs (64.1%) were either urban dogs that had been brought to rural areas (40.0%), or adopted dogs that had been previously abandoned in rural roads (24.1%). Some dogs were brought from areas located as far as ∼700km away from the study area. Human-mediated movement of dogs, especially from urban areas, seems to play a fundamental role in the population dynamics of dogs in rural areas. Consequently, local scale efforts to manage dog populations or their diseases are unlikely to succeed if implemented in isolation, simply because dogs can be brought from surrounding urban areas or even distant locations. We suggest that efforts to manage or study dog populations and related diseases should be implemented using a multi-scale approach. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Derivation of transgene-free human induced pluripotent stem cells from human peripheral T cells in defined culture conditions.

    Directory of Open Access Journals (Sweden)

    Yoshikazu Kishino

    Full Text Available Recently, induced pluripotent stem cells (iPSCs were established as promising cell sources for revolutionary regenerative therapies. The initial culture system used for iPSC generation needed fetal calf serum in the culture medium and mouse embryonic fibroblast as a feeder layer, both of which could possibly transfer unknown exogenous antigens and pathogens into the iPSC population. Therefore, the development of culture systems designed to minimize such potential risks has become increasingly vital for future applications of iPSCs for clinical use. On another front, although donor cell types for generating iPSCs are wide-ranging, T cells have attracted attention as unique cell sources for iPSCs generation because T cell-derived iPSCs (TiPSCs have a unique monoclonal T cell receptor genomic rearrangement that enables their differentiation into antigen-specific T cells, which can be applied to novel immunotherapies. In the present study, we generated transgene-free human TiPSCs using a combination of activated human T cells and Sendai virus under defined culture conditions. These TiPSCs expressed pluripotent markers by quantitative PCR and immunostaining, had a normal karyotype, and were capable of differentiating into cells from all three germ layers. This method of TiPSCs generation is more suitable for the therapeutic application of iPSC technology because it lowers the risks associated with the presence of undefined, animal-derived feeder cells and serum. Therefore this work will lead to establishment of safer iPSCs and extended clinical application.

  12. Selected microRNAs define cell fate determination of murine central memory CD8 T cells.

    Directory of Open Access Journals (Sweden)

    Gonzalo Almanza

    2010-06-01

    Full Text Available During an immune response T cells enter memory fate determination, a program that divides them into two main populations: effector memory and central memory T cells. Since in many systems protection appears to be preferentially mediated by T cells of the central memory it is important to understand when and how fate determination takes place. To date, cell intrinsic molecular events that determine their differentiation remains unclear. MicroRNAs are a class of small, evolutionarily conserved RNA molecules that negatively regulate gene expression, causing translational repression and/or messenger RNA degradation. Here, using an in vitro system where activated CD8 T cells driven by IL-2 or IL-15 become either effector memory or central memory cells, we assessed the role of microRNAs in memory T cell fate determination. We found that fate determination to central memory T cells is under the balancing effects of a discrete number of microRNAs including miR-150, miR-155 and the let-7 family. Based on miR-150 a new target, KChIP.1 (K (+ channel interacting protein 1, was uncovered, which is specifically upregulated in developing central memory CD8 T cells. Our studies indicate that cell fate determination such as surface phenotype and self-renewal may be decided at the pre-effector stage on the basis of the balancing effects of a discrete number of microRNAs. These results may have implications for the development of T cell vaccines and T cell-based adoptive therapies.

  13. Why patients visit their doctors: assessing the most prevalent conditions in a defined American population.

    Science.gov (United States)

    St Sauver, Jennifer L; Warner, David O; Yawn, Barbara P; Jacobson, Debra J; McGree, Michaela E; Pankratz, Joshua J; Melton, L Joseph; Roger, Véronique L; Ebbert, Jon O; Rocca, Walter A

    2013-01-01

    To describe the prevalence of nonacute conditions among patients seeking health care in a defined US population, emphasizing age, sex, and ethnic differences. The Rochester Epidemiology Project (REP) medical records linkage system was used to identify all residents of Olmsted County, Minnesota, on April 1, 2009, who had consented to review of their medical records for research (142,377 patients). We then electronically extracted all International Classification of Diseases, Ninth Revision codes noted in the records of these patients by any health care institution between January 1, 2005, and December 31, 2009. We grouped International Classification of Diseases, Ninth Revision codes into clinical classification codes and then into 47 broader disease groups associated with health-related quality of life. Age- and sex-specific prevalence was estimated by dividing the number of individuals within each group by the corresponding age- and sex-specific population. Patients within a group who had multiple codes were counted only once. We included a total of 142,377 patients, 75,512 (53%) of whom were female. Skin disorders (42.7%), osteoarthritis and joint disorders (33.6%), back problems (23.9%), disorders of lipid metabolism (22.4%), and upper respiratory tract disease (22.1%, excluding asthma) were the most prevalent disease groups in this population. Ten of the 15 most prevalent disease groups were more common in women in almost all age groups, whereas disorders of lipid metabolism, hypertension, and diabetes were more common in men. Additionally, the prevalence of 7 of the 10 most common groups increased with advancing age. Prevalence also varied across ethnic groups (whites, blacks, and Asians). Our findings suggest areas for focused research that may lead to better health care delivery and improved population health. Copyright © 2013 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

  14. Evaluation of a practical expert defined approach to patient population segmentation: a case study in Singapore

    Directory of Open Access Journals (Sweden)

    Lian Leng Low

    2017-11-01

    Full Text Available Abstract Background Segmenting the population into groups that are relatively homogeneous in healthcare characteristics or needs is crucial to facilitate integrated care and resource planning. We aimed to evaluate the feasibility of segmenting the population into discrete, non-overlapping groups using a practical expert and literature driven approach. We hypothesized that this approach is feasible utilizing the electronic health record (EHR in SingHealth. Methods In addition to well-defined segments of “Mostly healthy”, “Serious acute illness but curable” and “End of life” segments that are also present in the Ministry of Health Singapore framework, patients with chronic diseases were segmented into “Stable chronic disease”, “Complex chronic diseases without frequent hospital admissions”, and “Complex chronic diseases with frequent hospital admissions”. Using the electronic health record (EHR, we applied this framework to all adult patients who had a healthcare encounter in the Singapore Health Services Regional Health System in 2012. ICD-9, 10 and polyclinic codes were used to define chronic diseases with a comprehensive look-back period of 5 years. Outcomes (hospital admissions, emergency attendances, specialist outpatient clinic attendances and mortality were analyzed for years 2012 to 2015. Results Eight hundred twenty five thousand eight hundred seventy four patients were included in this study with the majority being healthy without chronic diseases. The most common chronic disease was hypertension. Patients with “complex chronic disease” with frequent hospital admissions segment represented 0.6% of the eligible population, but accounted for the highest hospital admissions (4.33 ± 2.12 admissions; p < 0.001 and emergency attendances (ED (3.21 ± 3.16 ED visits; p < 0.001 per patient, and a high mortality rate (16%. Patients with metastatic disease accounted for the highest specialist outpatient

  15. Cetuximab in locally advanced head-and-neck cancer: defining the population

    Science.gov (United States)

    Ho, C.

    2010-01-01

    Encouraging data for targeted therapy in head-and-neck squamous cell carcinoma are opening new options for treatment. Phase III trials of cetuximab, an antibody directed against the epidermal growth factor receptor (egfr) have demonstrated benefit in the locally advanced and metastatic settings. Recognizing the importance of emerging therapies, Cancer Care Ontario published guideline recommendations for egfr-targeted therapy in stage iii and iv head-and-neck cancer. The present paper takes a further look at the population for whom an offer of cetuximab therapy may be appropriate. PMID:20697514

  16. Defining POMC neurons using transgenic reagents: impact of transient Pomc expression in diverse immature neuronal populations.

    Science.gov (United States)

    Padilla, Stephanie L; Reef, Daniel; Zeltser, Lori M

    2012-03-01

    Melanocortin signaling plays a central role in the regulation of phenotypes related to body weight and energy homeostasis. To specifically target and study the function of proopiomelanocortin (POMC) neurons, Pomc promoter elements have been utilized to generate reporter and Cre recombinase transgenic reagents. Across gestation, we find that Pomc is dynamically expressed in many sites in the developing mouse forebrain, midbrain, hindbrain, spinal cord, and retina. Although Pomc expression in most embryonic brain regions is transient, it is sufficient to direct Cre-mediated recombination of floxed alleles. We visualize the populations affected by this transgene by crossing Pomc-Cre mice to ROSA reporter strains and identify 62 sites of recombination throughout the adult brain, including several nuclei implicated in energy homeostasis regulation. To compare the relationship between acute Pomc promoter activity and Pomc-Cre-mediated recombination at the single cell level, we crossed Pomc-enhanced green fluorescent protein (eGFP) and Pomc-Cre;ROSA-tdTomato lines. We detect the highest concentration of Pomc-eGFP+ cells in the arcuate nucleus of the hypothalamus and dentate gyrus but also observe smaller populations of labeled cells in the nucleus of the solitary tract, periventricular zone of the third ventricle, and cerebellum. Consistent with the dynamic nature of Pomc expression in the embryo, the vast majority of neurons marked with the tdTomato reporter do not express eGFP in the adult. Thus, recombination in off-target sites could contribute to physiological phenotypes using Pomc-Cre transgenics. For example, we find that approximately 83% of the cells in the arcuate nucleus of the hypothalamus immunoreactive for leptin-induced phosphorylated signal transducer and activator of transcription 3 are marked with Pomc-Cre;ROSA-tdTomato; only 13% of these are eGFP+ POMC neurons.

  17. Cell proliferation-associated nuclear antigen defined by antibody Ki-67: a new kind of cell cycle-maintaining proteins

    International Nuclear Information System (INIS)

    Duchrow, M.; Schlueter, C.; Key, G.; Kubbutat, H.G.; Wohlenberg, C.; Flad, H.D.; Gerdes

    1995-01-01

    A decade of studies on the human nuclear antigen defined by monoclonal antibody Ki-67 (the 'Ki-67 proteins') has made it abundantly clear that this structure is strictly associated with human cell proliferation and the expression of this protein can be used to access the growth fraction of a given cell population. Until recently the Ki-67 protein was described as a nonhistone protein that is highly susceptible to protease treatment. We have isolated and sequenced cDNAs encoding for this antigen and found two isoforms of the full length cDNA of 11.5 and 12.5 kb, respectively, sequence and structure of which are thus far unique. The gene encoding the Ki-67 protein is organized in 15 exons and is localized on chromosome 10. The center of this gene is formed by an extraordinary 6845 bp exon containing 16 successively repeated homologous segments of 366 bp ('Ki-67 repeats'), each containing a highly conserved new motif of 66 bp ('Ki-67 motif'). The deduced peptide sequence of this central exon possesses 10 ProGluSerThr (PEST) motifs which are associated with high turnover proteins such as other cell cycle-related proteins, oncogenes and transcription factors, etc. Like the latter proteins the Ki-67 antigen plays a pivotal role in maintaining cell proliferation because Ki-67 protein antisense oligonucleotides significantly inhibit 3 H-thymidine incorporation in permanent human tumor cell lines in a dose-dependent manner. (author). 30 refs, 2 figs

  18. Defining the identity of human adipose-derived mesenchymal stem cells.

    Science.gov (United States)

    Montelatici, Elisa; Baluce, Barbara; Ragni, Enrico; Lavazza, Cristiana; Parazzi, Valentina; Mazzola, Riccardo; Cantarella, Giovanna; Brambilla, Massimiliano; Giordano, Rosaria; Lazzari, Lorenza

    2015-02-01

    Adipose-derived mesenchymal stem cells (ADMSCs) are an ideal population for regenerative medical application. Both the isolation procedure and the culturing conditions are crucial steps, since low yield can limit further cell therapies, especially when minimal adipose tissue harvests are available for cell expansion. To date, a standardized procedure encompassing both isolation sites and expansion methods is missing, thus making the choice of the most appropriate conditions for the preparation of ADMSCs controversial, especially in view of the different applications needed. In this study, we compared the effects of three different commercial media (DMEM, aMEM, and EGM2), routinely used for ADMSCs expansion, and two supplements, FBS and human platelet lysate, recently proven to be an effective alternative to prevent xenogeneic antibody transfer and immune alloresponse in the host. Notably, all the conditions resulted in being safe for ADMSCs isolation and expansion with platelet lysate supplementation giving the highest isolation and proliferation rates, together with a commitment for osteogenic lineage. Then, we proved that the high ADMSC hematopoietic supportive potential is performed through a constant and abundant secretion of both GCSF and SCF. In conclusion, this study further expands the knowledge on ADMSCs, defining their identity definition and offers potential options for in vitro protocols for clinical production, especially related to HSC expansion without use of exogenous cytokines or genetic modifications.

  19. Rapid Induction of Cerebral Organoids From Human Induced Pluripotent Stem Cells Using a Chemically Defined Hydrogel and Defined Cell Culture Medium.

    Science.gov (United States)

    Lindborg, Beth A; Brekke, John H; Vegoe, Amanda L; Ulrich, Connor B; Haider, Kerri T; Subramaniam, Sandhya; Venhuizen, Scott L; Eide, Cindy R; Orchard, Paul J; Chen, Weili; Wang, Qi; Pelaez, Francisco; Scott, Carolyn M; Kokkoli, Efrosini; Keirstead, Susan A; Dutton, James R; Tolar, Jakub; O'Brien, Timothy D

    2016-07-01

    Tissue organoids are a promising technology that may accelerate development of the societal and NIH mandate for precision medicine. Here we describe a robust and simple method for generating cerebral organoids (cOrgs) from human pluripotent stem cells by using a chemically defined hydrogel material and chemically defined culture medium. By using no additional neural induction components, cOrgs appeared on the hydrogel surface within 10-14 days, and under static culture conditions, they attained sizes up to 3 mm in greatest dimension by day 28. Histologically, the organoids showed neural rosette and neural tube-like structures and evidence of early corticogenesis. Immunostaining and quantitative reverse-transcription polymerase chain reaction demonstrated protein and gene expression representative of forebrain, midbrain, and hindbrain development. Physiologic studies showed responses to glutamate and depolarization in many cells, consistent with neural behavior. The method of cerebral organoid generation described here facilitates access to this technology, enables scalable applications, and provides a potential pathway to translational applications where defined components are desirable. Tissue organoids are a promising technology with many potential applications, such as pharmaceutical screens and development of in vitro disease models, particularly for human polygenic conditions where animal models are insufficient. This work describes a robust and simple method for generating cerebral organoids from human induced pluripotent stem cells by using a chemically defined hydrogel material and chemically defined culture medium. This method, by virtue of its simplicity and use of defined materials, greatly facilitates access to cerebral organoid technology, enables scalable applications, and provides a potential pathway to translational applications where defined components are desirable. ©AlphaMed Press.

  20. Infundibular dilatation of the posterior communicating artery in a defined population.

    Science.gov (United States)

    Vlajković, Slobodan; Vasović, Ljiljana; Trandafilović, Milena; Jovanović, Ivan; Ugrenović, Slađana; Dorđević, Gordana

    2015-01-01

    Unusual widening of the posterior communicating artery (PCoA) at its beginning from the cerebral portion of the internal carotid artery (ICA) was described as its infundibular dilatation (ID). A possibility of ID rupture or progression to aneurysm was the reason for an investigation of its frequency and morphologic features in specimens of the Serbian population. Cerebral arteries on the brain base of 267 adult cadavers of both genders and varying age and causes of death were dissected. The images of the PCoA in 190 fetuses were also reviewed. ID of the PCoA was defined as a funnel shaped beginning of different width from ICA, wherein PCoA continues from ID apex to the posterior cerebral artery. There were no cases of ID in fetuses. ID and aneurysms of the PCoA were found in 6/267 or 2.2% and 3/267 or 1.12% of adults, respectively. Unilaterally, they existed on the left side and, frequently, in male cases aging 70 years and older, that had died without cerebral cause. Bilaterally, ID was found in 2/6 cases. There was only one case of ID and aneurysm of the PCoA, but from the ID. We are of the opinion that ID of the PCoA only develops postnatally and probably is due to the influence of hemodynamic factors or hypertension. Copyright © 2014 Elsevier GmbH. All rights reserved.

  1. Surface-engineered substrates for improved human pluripotent stem cell culture under fully defined conditions.

    Science.gov (United States)

    Saha, Krishanu; Mei, Ying; Reisterer, Colin M; Pyzocha, Neena Kenton; Yang, Jing; Muffat, Julien; Davies, Martyn C; Alexander, Morgan R; Langer, Robert; Anderson, Daniel G; Jaenisch, Rudolf

    2011-11-15

    The current gold standard for the culture of human pluripotent stem cells requires the use of a feeder layer of cells. Here, we develop a spatially defined culture system based on UV/ozone radiation modification of typical cell culture plastics to define a favorable surface environment for human pluripotent stem cell culture. Chemical and geometrical optimization of the surfaces enables control of early cell aggregation from fully dissociated cells, as predicted from a numerical model of cell migration, and results in significant increases in cell growth of undifferentiated cells. These chemically defined xeno-free substrates generate more than three times the number of cells than feeder-containing substrates per surface area. Further, reprogramming and typical gene-targeting protocols can be readily performed on these engineered surfaces. These substrates provide an attractive cell culture platform for the production of clinically relevant factor-free reprogrammed cells from patient tissue samples and facilitate the definition of standardized scale-up friendly methods for disease modeling and cell therapeutic applications.

  2. Experimental depletion of different renal interstitial cell populations

    International Nuclear Information System (INIS)

    Bohman, S.O.; Sundelin, B.; Forsum, U.; Tribukait, B.

    1988-01-01

    To define different populations of renal interstitial cells and investigate some aspects of their function, we studied the kidneys of normal rats and rats with hereditary diabetes insipidus (DI, Brattleboro) after experimental manipulations expected to alter the number of interstitial cells. DI rats showed an almost complete loss of interstitial cells in their renal papillae after treatment with a high dose of vasopressin. In spite of the lack of interstitial cells, the animals concentrated their urine to the same extent as vasopressin-treated normal rats, indicating that the renomedullary interstitial cells do not have an important function in concentrating the urine. The interstitial cells returned nearly to normal within 1 week off vasopressin treatment, suggesting a rapid turnover rate of these cells. To further distinguish different populations of interstitial cells, we studied the distribution of class II MHC antigen expression in the kidneys of normal and bone-marrow depleted Wistar rats. Normal rats had abundant class II antigen-positive interstitial cells in the renal cortex and outer medulla, but not in the inner medulla (papilla). Six days after 1000 rad whole body irradiation, the stainable cells were almost completely lost, but electron microscopic morphometry showed a virtually unchanged volume density of interstitial cells in the cortex and outer medulla, as well as the inner medulla. Thus, irradiation abolished the expression of the class II antigen but caused no significant depletion of interstitial cells

  3. Using satellite telemetry to define spatial population structure in polar bears in the Norwegian and western Russian Arctic

    Science.gov (United States)

    Mauritzen, Mette; Derocher, Andrew E.; Wiig, Øystein; Belikov, Stanislav; Boltunov, Andrei N.; Garner, Gerald W.

    2002-01-01

    1. Animal populations, defined by geographical areas within a species’ distribution where population dynamics are largely regulated by births and deaths rather than by migration from surrounding areas, may be the correct unit for wildlife management. However, in heterogeneous landscapes varying habitat quality may yield subpopulations with distinct patterns in resource use and demography significant to the dynamics of populations.2. To define the spatial population structure of polar bears Ursus maritimus in the Norwegian and western Russian Arctic, and to assess the existence of a shared population between the two countries, we analysed satellite telemetry data obtained from 105 female polar bears over 12 years.3. Using both cluster analyses and home-range estimation methods, we identified five population units inhabiting areas with different sea-ice characteristics and prey availability.4. The continuous distribution of polar bear positions indicated that the different subpopulations formed one continuous polar bear population in the Norwegian and western Russian Arctic. Hence, Norway and Russia have a shared management responsibility.5. The spatial population structure identified will provide a guide for evaluating geographical patterns in polar bear ecology, the dynamics of polar bear–seal relationships and the effects of habitat alteration due to climate change. The work illustrates the importance of defining population borders and subpopulation structure in understanding the dynamics and management of larger animals.

  4. Deconstructing stem cell population heterogeneity: Single-cell analysis and modeling approaches

    Science.gov (United States)

    Wu, Jincheng; Tzanakakis, Emmanuel S.

    2014-01-01

    Isogenic stem cell populations display cell-to-cell variations in a multitude of attributes including gene or protein expression, epigenetic state, morphology, proliferation and proclivity for differentiation. The origins of the observed heterogeneity and its roles in the maintenance of pluripotency and the lineage specification of stem cells remain unclear. Addressing pertinent questions will require the employment of single-cell analysis methods as traditional cell biochemical and biomolecular assays yield mostly population-average data. In addition to time-lapse microscopy and flow cytometry, recent advances in single-cell genomic, transcriptomic and proteomic profiling are reviewed. The application of multiple displacement amplification, next generation sequencing, mass cytometry and spectrometry to stem cell systems is expected to provide a wealth of information affording unprecedented levels of multiparametric characterization of cell ensembles under defined conditions promoting pluripotency or commitment. Establishing connections between single-cell analysis information and the observed phenotypes will also require suitable mathematical models. Stem cell self-renewal and differentiation are orchestrated by the coordinated regulation of subcellular, intercellular and niche-wide processes spanning multiple time scales. Here, we discuss different modeling approaches and challenges arising from their application to stem cell populations. Integrating single-cell analysis with computational methods will fill gaps in our knowledge about the functions of heterogeneity in stem cell physiology. This combination will also aid the rational design of efficient differentiation and reprogramming strategies as well as bioprocesses for the production of clinically valuable stem cell derivatives. PMID:24035899

  5. Digital microfabrication of user-defined 3D microstructures in cell-laden hydrogels.

    Science.gov (United States)

    Soman, Pranav; Chung, Peter H; Zhang, A Ping; Chen, Shaochen

    2013-11-01

    Complex 3D interfacial arrangements of cells are found in several in vivo biosystems such as blood vasculature, renal glomeruli, and intestinal villi. Current tissue engineering techniques fail to develop suitable 3D microenvironments to evaluate the concurrent effects of complex topography and cell encapsulation. There is a need to develop new fabrication approaches that control cell density and distribution within complex 3D features. In this work, we present a dynamic projection printing process that allows rapid construction of complex 3D structures using custom-defined computer-aided-design (CAD) files. Gelatin-methacrylate (GelMA) constructs featuring user-defined spiral, pyramid, flower, and dome micro-geometries were fabricated with and without encapsulated cells. Encapsulated cells demonstrate good cell viability across all geometries both on the scaffold surface and internal to the structures. Cells respond to geometric cues individually as well as collectively throughout the larger-scale patterns. Time-lapse observations also reveal the dynamic nature of mechanical interactions between cells and micro-geometry. When compared to conventional cell-seeding, cell encapsulation within complex 3D patterned scaffolds provides long-term control over proliferation, cell morphology, and geometric guidance. Overall, this biofabrication technique offers a flexible platform to evaluate cell interactions with complex 3D micro-features, with the ability to scale-up towards high-throughput screening platforms. © 2013 Wiley Periodicals, Inc.

  6. CD19 CAR-T cells of defined CD4+:CD8+ composition in adult B cell ALL patients.

    Science.gov (United States)

    Turtle, Cameron J; Hanafi, Laïla-Aïcha; Berger, Carolina; Gooley, Theodore A; Cherian, Sindhu; Hudecek, Michael; Sommermeyer, Daniel; Melville, Katherine; Pender, Barbara; Budiarto, Tanya M; Robinson, Emily; Steevens, Natalia N; Chaney, Colette; Soma, Lorinda; Chen, Xueyan; Yeung, Cecilia; Wood, Brent; Li, Daniel; Cao, Jianhong; Heimfeld, Shelly; Jensen, Michael C; Riddell, Stanley R; Maloney, David G

    2016-06-01

    T cells that have been modified to express a CD19-specific chimeric antigen receptor (CAR) have antitumor activity in B cell malignancies; however, identification of the factors that determine toxicity and efficacy of these T cells has been challenging in prior studies in which phenotypically heterogeneous CAR-T cell products were prepared from unselected T cells. We conducted a clinical trial to evaluate CD19 CAR-T cells that were manufactured from defined CD4+ and CD8+ T cell subsets and administered in a defined CD4+:CD8+ composition to adults with B cell acute lymphoblastic leukemia after lymphodepletion chemotherapy. The defined composition product was remarkably potent, as 27 of 29 patients (93%) achieved BM remission, as determined by flow cytometry. We established that high CAR-T cell doses and tumor burden increase the risks of severe cytokine release syndrome and neurotoxicity. Moreover, we identified serum biomarkers that allow testing of early intervention strategies in patients at the highest risk of toxicity. Risk-stratified CAR-T cell dosing based on BM disease burden decreased toxicity. CD8+ T cell-mediated anti-CAR transgene product immune responses developed after CAR-T cell infusion in some patients, limited CAR-T cell persistence, and increased relapse risk. Addition of fludarabine to the lymphodepletion regimen improved CAR-T cell persistence and disease-free survival. Immunotherapy with a CAR-T cell product of defined composition enabled identification of factors that correlated with CAR-T cell expansion, persistence, and toxicity and facilitated design of lymphodepletion and CAR-T cell dosing strategies that mitigated toxicity and improved disease-free survival. ClinicalTrials.gov NCT01865617. R01-CA136551; Life Science Development Fund; Juno Therapeutics; Bezos Family Foundation.

  7. Phenotype heterogeneity in cancer cell populations

    International Nuclear Information System (INIS)

    Almeida, Luis; Chisholm, Rebecca; Clairambault, Jean; Escargueil, Alexandre; Lorenzi, Tommaso; Lorz, Alexander; Trélat, Emmanuel

    2016-01-01

    Phenotype heterogeneity in cancer cell populations, be it of genetic, epigenetic or stochastic origin, has been identified as a main source of resistance to drug treatments and a major source of therapeutic failures in cancers. The molecular mechanisms of drug resistance are partly understood at the single cell level (e.g., overexpression of ABC transporters or of detoxication enzymes), but poorly predictable in tumours, where they are hypothesised to rely on heterogeneity at the cell population scale, which is thus the right level to describe cancer growth and optimise its control by therapeutic strategies in the clinic. We review a few results from the biological literature on the subject, and from mathematical models that have been published to predict and control evolution towards drug resistance in cancer cell populations. We propose, based on the latter, optimisation strategies of combined treatments to limit emergence of drug resistance to cytotoxic drugs in cancer cell populations, in the monoclonal situation, which limited as it is still retains consistent features of cell population heterogeneity. The polyclonal situation, that may be understood as “bet hedging” of the tumour, thus protecting itself from different sources of drug insults, may lie beyond such strategies and will need further developments. In the monoclonal situation, we have designed an optimised therapeutic strategy relying on a scheduled combination of cytotoxic and cytostatic treatments that can be adapted to different situations of cancer treatments. Finally, we review arguments for biological theoretical frameworks proposed at different time and development scales, the so-called atavistic model (diachronic view relying on Darwinian genotype selection in the coursof billions of years) and the Waddington-like epigenetic landscape endowed with evolutionary quasi-potential (synchronic view relying on Lamarckian phenotype instruction of a given genome by reversible mechanisms), to

  8. Phenotype heterogeneity in cancer cell populations

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Luis [CNRS UMR 7598, LJLL, & INRIA MAMBA team, Sorbonne Universités, UPMC Univ Paris 06, Boîte courrier 187, 4 Pl. Jussieu, 75252 Paris cedex 05, France, luis@ann.jussieu.fr (France); Chisholm, Rebecca [School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, Australia, rebecca.chisholm@gmail.com (Australia); Clairambault, Jean [INRIA MAMBA team & LJLL, UMR 7598, Sorbonne Universités, UPMC Univ Paris 06, Boîte courrier 187, 4 Pl. Jussieu, 75252 Paris cedex 05, France, jean.clairambault@inria.fr, Corresponding author (France); Escargueil, Alexandre [INSERM “Cancer Biology and Therapeutics”, Sorbonne Universités, UPMC Univ Paris 06, UMR-S 938, CDR St Antoine, Hôpital St Antoine, 184 Fbg. St Antoine, 75571 Paris cedex 12, France, alexandre.escargueil@upmc.fr (France); Lorenzi, Tommaso [CMLA, ENS Cachan, 61, Av. du Président Wilson, 94230 Cachan cedex & INRIA MAMBA team, & LJLL, UMR 7598, UPMC Univ Paris 06, Boîte courrier 187, 4 Pl. Jussieu, 75252 Paris cedex 05, France, tommaso.lorenzi@gmail.com (France); Lorz, Alexander [Sorbonne Universités, UPMC Univ Paris 06, LJLL, UMR 7598 & INRIA Boîte courrier 187, 4 Pl. Jussieu, 75252 Paris cedex 05, France, alex.lorz@ann.jussieu.fr (France); Trélat, Emmanuel [Institut Universitaire de France, Sorbonne Universités, UPMC Univ Paris 06, LJLL, UMR 7598, Boîte courrier 187, UPMC Univ Paris 06, 4 Pl. Jussieu, 75252 Paris cedex 05, France, emmanuel.trelat@upmc.fr (France)

    2016-06-08

    Phenotype heterogeneity in cancer cell populations, be it of genetic, epigenetic or stochastic origin, has been identified as a main source of resistance to drug treatments and a major source of therapeutic failures in cancers. The molecular mechanisms of drug resistance are partly understood at the single cell level (e.g., overexpression of ABC transporters or of detoxication enzymes), but poorly predictable in tumours, where they are hypothesised to rely on heterogeneity at the cell population scale, which is thus the right level to describe cancer growth and optimise its control by therapeutic strategies in the clinic. We review a few results from the biological literature on the subject, and from mathematical models that have been published to predict and control evolution towards drug resistance in cancer cell populations. We propose, based on the latter, optimisation strategies of combined treatments to limit emergence of drug resistance to cytotoxic drugs in cancer cell populations, in the monoclonal situation, which limited as it is still retains consistent features of cell population heterogeneity. The polyclonal situation, that may be understood as “bet hedging” of the tumour, thus protecting itself from different sources of drug insults, may lie beyond such strategies and will need further developments. In the monoclonal situation, we have designed an optimised therapeutic strategy relying on a scheduled combination of cytotoxic and cytostatic treatments that can be adapted to different situations of cancer treatments. Finally, we review arguments for biological theoretical frameworks proposed at different time and development scales, the so-called atavistic model (diachronic view relying on Darwinian genotype selection in the coursof billions of years) and the Waddington-like epigenetic landscape endowed with evolutionary quasi-potential (synchronic view relying on Lamarckian phenotype instruction of a given genome by reversible mechanisms), to

  9. Phenotype heterogeneity in cancer cell populations

    Science.gov (United States)

    Almeida, Luis; Chisholm, Rebecca; Clairambault, Jean; Escargueil, Alexandre; Lorenzi, Tommaso; Lorz, Alexander; Trélat, Emmanuel

    2016-06-01

    Phenotype heterogeneity in cancer cell populations, be it of genetic, epigenetic or stochastic origin, has been identified as a main source of resistance to drug treatments and a major source of therapeutic failures in cancers. The molecular mechanisms of drug resistance are partly understood at the single cell level (e.g., overexpression of ABC transporters or of detoxication enzymes), but poorly predictable in tumours, where they are hypothesised to rely on heterogeneity at the cell population scale, which is thus the right level to describe cancer growth and optimise its control by therapeutic strategies in the clinic. We review a few results from the biological literature on the subject, and from mathematical models that have been published to predict and control evolution towards drug resistance in cancer cell populations. We propose, based on the latter, optimisation strategies of combined treatments to limit emergence of drug resistance to cytotoxic drugs in cancer cell populations, in the monoclonal situation, which limited as it is still retains consistent features of cell population heterogeneity. The polyclonal situation, that may be understood as "bet hedging" of the tumour, thus protecting itself from different sources of drug insults, may lie beyond such strategies and will need further developments. In the monoclonal situation, we have designed an optimised therapeutic strategy relying on a scheduled combination of cytotoxic and cytostatic treatments that can be adapted to different situations of cancer treatments. Finally, we review arguments for biological theoretical frameworks proposed at different time and development scales, the so-called atavistic model (diachronic view relying on Darwinian genotype selection in the coursof billions of years) and the Waddington-like epigenetic landscape endowed with evolutionary quasi-potential (synchronic view relying on Lamarckian phenotype instruction of a given genome by reversible mechanisms), to

  10. Ta1, a novel 105 KD human T cell activation antigen defined by a monoclonal antibody.

    Science.gov (United States)

    Fox, D A; Hussey, R E; Fitzgerald, K A; Acuto, O; Poole, C; Palley, L; Daley, J F; Schlossman, S F; Reinherz, E L

    1984-09-01

    By using a murine monoclonal antibody produced against an IL 2-dependent human T cell line, we defined a T lineage-specific molecule, termed Ta1, that is expressed strongly on activated T lymphocytes of both the T4 and T8 subsets, as well as on T cell lines and clones, but only weakly on a fraction of resting T cells. SDS-PAGE analysis of immunoprecipitates from 125I-labeled, activated T cells demonstrates a single major band of apparent m.w. 105 KD under both reducing and nonreducing conditions. Unlike anti-IL 2 receptor antibodies, anti-Ta1 does not inhibit T cell proliferative responses to mitogen, antigen, or IL 2-containing medium. Moreover, anti-Ta1 has no effect on T cell-mediated cytotoxicity. Ta1 appears to be a novel human T cell-specific activation antigen that may serve as a useful marker of T cell activation in human disease.

  11. CD19 CAR–T cells of defined CD4+:CD8+ composition in adult B cell ALL patients

    Science.gov (United States)

    Turtle, Cameron J.; Hanafi, Laïla-Aïcha; Berger, Carolina; Gooley, Theodore A.; Cherian, Sindhu; Hudecek, Michael; Sommermeyer, Daniel; Melville, Katherine; Pender, Barbara; Budiarto, Tanya M.; Robinson, Emily; Steevens, Natalia N.; Chaney, Colette; Soma, Lorinda; Chen, Xueyan; Li, Daniel; Cao, Jianhong; Heimfeld, Shelly; Jensen, Michael C.; Riddell, Stanley R.; Maloney, David G.

    2016-01-01

    BACKGROUND. T cells that have been modified to express a CD19-specific chimeric antigen receptor (CAR) have antitumor activity in B cell malignancies; however, identification of the factors that determine toxicity and efficacy of these T cells has been challenging in prior studies in which phenotypically heterogeneous CAR–T cell products were prepared from unselected T cells. METHODS. We conducted a clinical trial to evaluate CD19 CAR–T cells that were manufactured from defined CD4+ and CD8+ T cell subsets and administered in a defined CD4+:CD8+ composition to adults with B cell acute lymphoblastic leukemia after lymphodepletion chemotherapy. RESULTS. The defined composition product was remarkably potent, as 27 of 29 patients (93%) achieved BM remission, as determined by flow cytometry. We established that high CAR–T cell doses and tumor burden increase the risks of severe cytokine release syndrome and neurotoxicity. Moreover, we identified serum biomarkers that allow testing of early intervention strategies in patients at the highest risk of toxicity. Risk-stratified CAR–T cell dosing based on BM disease burden decreased toxicity. CD8+ T cell–mediated anti-CAR transgene product immune responses developed after CAR–T cell infusion in some patients, limited CAR–T cell persistence, and increased relapse risk. Addition of fludarabine to the lymphodepletion regimen improved CAR–T cell persistence and disease-free survival. CONCLUSION. Immunotherapy with a CAR–T cell product of defined composition enabled identification of factors that correlated with CAR–T cell expansion, persistence, and toxicity and facilitated design of lymphodepletion and CAR–T cell dosing strategies that mitigated toxicity and improved disease-free survival. TRIAL REGISTRATION. ClinicalTrials.gov NCT01865617. FUNDING. R01-CA136551; Life Science Development Fund; Juno Therapeutics; Bezos Family Foundation. PMID:27111235

  12. Radiosensitivity of defined populations of lymphocytes. VI. Functional, structural, and biochemical consequences of in vitro irradiation

    International Nuclear Information System (INIS)

    Anderson, R.E.; Standefer, J.C.; Scaletti, J.V.

    1977-01-01

    Single cell suspensions of BALB/c thymocytes (T cells) and nu/nu spleen cells (B cells) were exposed to 0, 50, and 500 rads and examined for topological abnormalities and alterations in surface glycoproteins and capacity to traffic normally upon transfer to syngeneic recipients. The results show that irradiated lymphocytes from both sources undergo extensive topological alterations which become more pronounced with the passage of time and which appear to precede the loss of cell viability. Viable T and B cells irradiated in vitro also fail to recirculate normally and accumulate in abnormal proportions in the spleen at the expense of the lymph nodes and gut-associated lymphoid tissues. Similarly, after a 2-hr incubation in saline at room temperature, irradiation of both T and B cells resulted in alterations in extractable surface glycoproteins. The results are consistent with the hypothesis that alterations in the rcirculation of irradiated lymphocytes are associated with alterations in the plasma membrane

  13. Defining a stem cell hierarchy in the intestine: markers, caveats and controversies

    Science.gov (United States)

    Smith, Nicholas R.; Gallagher, Alexandra C.

    2016-01-01

    Abstract The past decade has appreciated rapid advance in identifying the once elusive intestinal stem cell (ISC) populations that fuel the continual renewal of the epithelial layer. This advance was largely driven by identification of novel stem cell marker genes, revealing the existence of quiescent, slowly‐ and active‐cycling ISC populations. However, a critical barrier for translating this knowledge to human health and disease remains elucidating the functional interplay between diverse stem cell populations. Currently, the precise hierarchical and regulatory relationships between these ISC populations are under intense scrutiny. The classical theory of a linear hierarchy, where quiescent and slowly‐cycling stem cells self‐renew but replenish an active‐cycling population, is well established in other rapidly renewing tissues such as the haematopoietic system. Efforts to definitively establish a similar stem cell hierarchy within the intestinal epithelium have yielded conflicting results, been difficult to interpret, and suggest non‐conventional alternatives to a linear hierarchy. While these new and potentially paradigm‐shifting discoveries are intriguing, the field will require development of a number of critical tools, including highly specific stem cell marker genes along with more rigorous experimental methodologies, to delineate the complex cellular relationships within this dynamic organ system. PMID:26864260

  14. Population hemoglobin mean and anemia prevalence in Papua New Guinea: new metrics for defining malaria endemicity?

    Directory of Open Access Journals (Sweden)

    Nicolas Senn

    Full Text Available BACKGROUND: The hypothesis is that hemoglobin-based metrics are useful tools for estimating malaria endemicity and for monitoring malaria control strategies. The aim of this study is to compare population hemoglobin mean and anemia prevalence to established indicators of malaria endemicity, including parasite rates, rates of enlarged spleens in children, and records of (presumptive malaria diagnosis among populations living with different levels of malaria transmission. METHODOLOGY/PRINCIPAL FINDINGS: Convenience sample, multisite cross-sectional household surveys conducted in Papua New Guinea. Correlations (r(2 between population Hb mean and anemia prevalence and altitude, parasite rate, and spleen rate were investigated in children ages 2 to 10 years, and in the general population; 21,664 individuals from 156 different communities were surveyed. Altitude ranged from 5 to 2120 meters. In young children, correlations between altitude and parasite rate, population Hb mean, anemia prevalence, and spleen rate were high (r(2: -0.77, 0.73, -0.81, and -0.68; p1500 m (p<0.001. CONCLUSIONS/SIGNIFICANCE: In PNG, where Plasmodium vivax accounts for an important part of all malaria infections, population hemoglobin mean and anemia prevalence correlate well with altitude, parasite, and spleen rates. Hb measurement is simple and affordable, and may be a useful new tool, alone or in association with other metrics, for estimating malaria endemicity and monitoring effectiveness of malaria control programs. Further prospective studies in areas with different malaria epidemiology and different factors contributing to the burden of anemia are warranted to investigate the usefulness of Hb metrics in monitoring malaria transmission intensity.

  15. Variations in Humanized and Defined Culture Conditions Supporting Derivation of New Human Embryonic Stem Cell Lines

    DEFF Research Database (Denmark)

    Fletcher, Judy M; Ferrier, Patricia M; Gardner, John O

    2006-01-01

    matrix substrate of purified human laminin (Ln) with transitional reliance on mitotically inactivated human fibroblast (HDF) feeder cells. With this integrated system hESC lines were isolated using either HDF conditioned medium supplemented with a bovine-sourced serum replacement (bSRM), or a defined...

  16. Interval scanning photomicrography of microbial cell populations.

    Science.gov (United States)

    Casida, L. E., Jr.

    1972-01-01

    A single reproducible area of the preparation in a fixed focal plane is photographically scanned at intervals during incubation. The procedure can be used for evaluating the aerobic or anaerobic growth of many microbial cells simultaneously within a population. In addition, the microscope is not restricted to the viewing of any one microculture preparation, since the slide cultures are incubated separately from the microscope.

  17. Early local differentiation of the cell wall matrix defines the contact sites in lobed mesophyll cells of Zea mays.

    Science.gov (United States)

    Giannoutsou, E; Sotiriou, P; Apostolakos, P; Galatis, B

    2013-10-01

    The morphogenesis of lobed mesophyll cells (MCs) is highly controlled and coupled with intercellular space formation. Cortical microtubule rings define the number and the position of MC isthmi. This work investigated early events of MC morphogenesis, especially the mechanism defining the position of contacts between MCs. The distributions of plasmodesmata, the hemicelluloses callose and (1 → 3,1 → 4)-β-d-glucans (MLGs) and the pectin epitopes recognized by the 2F4, JIM5, JIM7 and LM6 antibodies were studied in the cell walls of Zea mays MCs. Matrix cell wall polysaccharides were immunolocalized in hand-made sections and in sections of material embedded in LR White resin. Callose was also localized using aniline blue in hand-made sections. Plasmodesmata distribution was examined by transmission electron microscopy. Before reorganization of the dispersed cortical microtubules into microtubule rings, particular bands of the longitudinal MC walls, where the MC contacts will form, locally differentiate by selective (1) deposition of callose and the pectin epitopes recognized by the 2F4, LM6, JIM5 and JIM7 antibodies, (2) degradation of MLGs and (3) formation of secondary plasmodesmata clusterings. This cell wall matrix differentiation persists in cell contacts of mature MCs. Simultaneously, the wall bands between those of future cell contacts differentiate with (1) deposition of local cell wall thickenings including cellulose microfibrils, (2) preferential presence of MLGs, (3) absence of callose and (4) transient presence of the pectins identified by the JIM5 and JIM7 antibodies. The wall areas between cell contacts expand determinately to form the cell isthmi and the cell lobes. The morphogenesis of lobed MCs is characterized by the early patterned differentiation of two distinct cell wall subdomains, defining the sites of the future MC contacts and of the future MC isthmi respectively. This patterned cell wall differentiation precedes cortical microtubule

  18. Assessing return on investment of defined-population disease management interventions.

    Science.gov (United States)

    Wilson, Thomas W; Gruen, Jeff; William, Thar; Fetterolf, Donald; Minalkumar, Patel; Popiel, Richard G; Lewis, Al; Nash, David B

    2004-11-01

    Strategies to reduce health expenditures through the improvement of health and quality of care are in high demand. A group of experts formed a nonpartisan, independent work group, under the sponsorship of the National Managed Health Care Congress. Its goal was to establish a list of easy-to-understand, actionable, and usable recommendations to enable disease management program advocates to conduct basic-level evaluations. The work group made recommendations concerning identification of reference and intervention population, population definitions, quantitative methods and data quality, confounding and bias, and stakeholder agreements/contracting. A case study was created to quantitatively illustrate some of the major issues raised by the work group. Five typical errors were simulated by applying different rules to the intervention population than to the reference population: differential inclusion (high versus low risk), differential exclusion (high versus low risk) and differential claims run-out. Compared with the true impact, four of the five errors resulted in a bias toward "intervention effect," while one (differential inclusion of high-risk patients) was biased against the "intervention effect." The direction and magnitude of the bias in natural settings will not necessarily follow this pattern.

  19. Defining normal liver stiffness range in a normal healthy Chinese population without liver disease.

    Directory of Open Access Journals (Sweden)

    James Fung

    Full Text Available BACKGROUND: For patients with chronic liver disease, different optimal liver stiffness cut-off values correspond to different stages of fibrosis, which are specific for the underlying liver disease and population. AIMS: To establish the normal ranges of liver stiffness in the healthy Chinese population without underlying liver disease. METHODS: This is a prospective cross sectional study of 2,528 healthy volunteers recruited from the general population and the Red Cross Transfusion Center in Hong Kong. All participants underwent a comprehensive questionnaire survey, measurement of weight, height, and blood pressure. Fasting liver function tests, glucose and cholesterol was performed. Abdominal ultrasound and transient elastography were performed on all participants. RESULTS: Of the 2,528 subjects, 1,998 were excluded with either abnormal liver parenchyma on ultrasound, chronic medical condition, abnormal blood tests including liver enzymes, fasting glucose, fasting cholesterol, high body mass index, high blood pressure, or invalid liver stiffness scan. The reference range for the 530 subjects without known liver disease was 2.3 to 5.9 kPa (mean 4.1, SD 0.89. The median liver stiffness was higher in males compared with females (4.3 vs 4.0 kPa respectively, p55 years (p=0.001. CONCLUSIONS: The healthy reference range for liver stiffness in the Chinese population is 2.3 to 5.9 kPa. Female gender and older age group was associated with a lower median liver stiffness.

  20. Refining and defining riverscape genetics: How rivers influence population genetic structure

    Science.gov (United States)

    Chanté D. Davis; Clinton W. Epps; Rebecca L. Flitcroft; Michael A. Banks

    2018-01-01

    Traditional analysis in population genetics evaluates differences among groups of individuals and, in some cases, considers the effects of distance or potential barriers to gene flow. Genetic variation of organisms in complex landscapes, seascapes, or riverine systems, however, may be shaped by many forces. Recent research has linked habitat heterogeneity and landscape...

  1. Detecting Signatures of Positive Selection along Defined Branches of a Population Tree Using LSD.

    Science.gov (United States)

    Librado, Pablo; Orlando, Ludovic

    2018-06-01

    Identifying the genomic basis underlying local adaptation is paramount to evolutionary biology, and bears many applications in the fields of conservation biology, crop, and animal breeding, as well as personalized medicine. Although many approaches have been developed to detect signatures of positive selection within single populations and population pairs, the increasing wealth of high-throughput sequencing data requires improved methods capable of handling multiple, and ideally large number of, populations in a single analysis. In this study, we introduce LSD (levels of exclusively shared differences), a fast and flexible framework to perform genome-wide selection scans, along the internal and external branches of a given population tree. We use forward simulations to demonstrate that LSD can identify branches targeted by positive selection with remarkable sensitivity and specificity. We illustrate a range of potential applications by analyzing data from the 1000 Genomes Project and uncover a list of adaptive candidates accompanying the expansion of anatomically modern humans out of Africa and their spread to Europe.

  2. An examination of the prevalence of IDF- and ATPIII-defined metabolic syndrome in an Irish screening population.

    LENUS (Irish Health Repository)

    Waterhouse, D F

    2012-02-01

    OBJECTIVES: To investigate the prevalence of ATPIII- and IDF-defined metabolic syndrome (MetS) in an Irish screening population and to determine the calculated cardiovascular risk for each group. DESIGN: A total of 1,716 subjects were enrolled over a 12-month period. MAIN OUTCOMES: The ATPIII-defined prevalence of MetS in this population was 13.2%. Using IDF criteria, 21.4% of subjects were identified as having the MetS. Correlation between the two definitions was high; however, IDF criteria identified an additional 9.5% (n = 164) of the population as having MetS, which ATPIII criteria failed to recognise. CONCLUSION: We noted a higher prevalence of MetS in the studied population when defined by IDF criteria. However, those identified by IDF and not by ATPIII definition did not have a higher cardiovascular risk score by either Framingham or European Score than those without MetS. Thus, application of the ATPIII definition of MetS, may be the more practical.

  3. Cell-Type-Specific Gene Programs of the Normal Human Nephron Define Kidney Cancer Subtypes.

    Science.gov (United States)

    Lindgren, David; Eriksson, Pontus; Krawczyk, Krzysztof; Nilsson, Helén; Hansson, Jennifer; Veerla, Srinivas; Sjölund, Jonas; Höglund, Mattias; Johansson, Martin E; Axelson, Håkan

    2017-08-08

    Comprehensive transcriptome studies of cancers often rely on corresponding normal tissue samples to serve as a transcriptional reference. In this study, we performed in-depth analyses of normal kidney tissue transcriptomes from the TCGA and demonstrate that the histological variability in cellularity, inherent in the kidney architecture, lead to considerable transcriptional differences between samples. This should be considered when comparing expression profiles of normal and cancerous kidney tissues. We exploited these differences to define renal-cell-specific gene signatures and used these as a framework to analyze renal cell carcinoma (RCC) ontogeny. Chromophobe RCCs express FOXI1-driven genes that define collecting duct intercalated cells, whereas HNF-regulated genes, specific for proximal tubule cells, are an integral part of clear cell and papillary RCC transcriptomes. These networks may be used as a framework for understanding the interplay between genomic changes in RCC subtypes and the lineage-defining regulatory machinery of their non-neoplastic counterparts. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  4. Targeting population heterogeneity for optimal cell factories

    DEFF Research Database (Denmark)

    Heins, Anna-Lena; Carlqvist, Magnus; Helmark, S.

    the heterogeneity level of the population. To further investigate these phenomena and gain a deeper understanding of population heterogeneity, Saccharomyces cerevisiae growth reporter strains based on the expression of green fluorescent protein (GFP) were constructed which enabled us to perform single cell level...... analysis, and thereby created the possibility to map population heterogeneity. A factorial design with pH, glucose concentration and oxygen level was performed in batch cultivations using the growth reporter strains to evaluate the effect of those environmental factors on heterogeneity level and amount......To achieve an efficient production process, it is essential to optimize both the strain and the cultivation conditions. Traditionally, a microbial population has been considered homogeneous in optimization studies of fermentation processes. However, research has shown that a typical microbial...

  5. The effect of churn on "community viral load" in a well-defined regional population.

    Science.gov (United States)

    Krentz, Hartmut B; Gill, M John

    2013-10-01

    The concept of community viral load (CVL) was introduced to quantify the pool of transmissible HIV within a community and to monitor the potential impact of highly active antiretroviral therapy (HAART) on reducing new infections. The implications of churn (patient movement in/out of care in a community) on CVL have not been studied. The annual CVL was determined in the entire geographic HIV population receiving care in southern Alberta from 2001 to 2010; the CVL for specific subpopulations was analyzed for 2009. CVL was determined for patients under continuous care, newly diagnosed, new to the region, moved away, returned, and lost to follow-up (LTFU). Viral loads (VLs) churn significantly limited CVL use as a measure for evaluating the impact of HAART in reducing HIV transmissions in our population.

  6. Defining mtDNA origins and population stratification in Rio de Janeiro.

    Science.gov (United States)

    Simão, Filipa; Ferreira, Ana Paula; de Carvalho, Elizeu Fagundes; Parson, Walther; Gusmão, Leonor

    2018-05-01

    The genetic composition of the Brazilian population was shaped by interethnic admixture between autochthonous Native Americans, Europeans settlers and African slaves. This structure, characteristic of most American populations, implies the need for large population forensic databases to capture the high diversity that is usually associated with admixed populations. In the present work, we sequenced the control region of mitochondrial DNA from 205 non-related individuals living in the Rio de Janeiro metropolitan region. Overall high haplotype diversity (0.9994 ± 0.0006) was observed, and pairwise comparisons showed a high proportion of haplotype pairs with more than one-point differences. When ignoring homopolymeric tracts, pairwise comparisons showed no differences 0.18% of the time, and differences in a single position were found with a frequency of 0.32%. A high percentage of African mtDNA was found (42%), with lineages showing a major South West origin. For the West Eurasian and Native American haplogroups (representing 32% and 26%, respectively) it was not possible to evaluate a clear geographic or linguistic affiliation. When grouping the mtDNA lineages according to their continental origin (Native American, European and African), differences were observed for the ancestry proportions estimated with autosomal ancestry-informative markers, suggesting some level of genetic substructure. The results from this study are in accordance with historical data where admixture processes are confirmed with a strong maternal contribution of African maternal ancestry and a relevant contribution of Native American maternal ancestry. Moreover, the evidence for some degree of association between mtDNA and autosomal information should be considered when combining these types of markers in forensic analysis. Copyright © 2018 Elsevier B.V. All rights reserved.

  7. CD4+ T cell effects on CD8+ T cell location defined using bioluminescence.

    Directory of Open Access Journals (Sweden)

    Mitra Azadniv

    2011-01-01

    Full Text Available T lymphocytes of the CD8+ class are critical in delivering cytotoxic function and in controlling viral and intracellular infections. These cells are "helped" by T lymphocytes of the CD4+ class, which facilitate their activation, clonal expansion, full differentiation and the persistence of memory. In this study we investigated the impact of CD4+ T cells on the location of CD8+ T cells, using antibody-mediated CD4+ T cell depletion and imaging the antigen-driven redistribution of bioluminescent CD8+ T cells in living mice. We documented that CD4+ T cells influence the biodistribution of CD8+ T cells, favoring their localization to abdominal lymph nodes. Flow cytometric analysis revealed that this was associated with an increase in the expression of specific integrins. The presence of CD4+ T cells at the time of initial CD8+ T cell activation also influences their biodistribution in the memory phase. Based on these results, we propose the model that one of the functions of CD4+ T cell "help" is to program the homing potential of CD8+ T cells.

  8. Arf6, Rab11 and transferrin receptor define distinct populations of recycling endosomes.

    Science.gov (United States)

    Kobayashi, Hotaka; Fukuda, Mitsunori

    2013-09-01

    Recycling endosomes are key platforms for endocytic recycling that return internalized molecules back to the plasma membrane. To determine how recycling endosomes perform their functions, searching for proteins and lipids that specifically localized at recycling endosomes has often been performed by colocalization analyses between candidate molecules and conventional recycling endosome markers. However, it remains unclear whether all the conventional markers have identical localizations. Here we report finding that three well-known recycling endosome markers, i.e., Arf6, Rab11 and transferrin receptor (TfR), have different intracellular localizations in PC12 cells. The results of immunofluorescence analyses showed that the signals of endogenous Arf6, Rab11 and TfR in nerve growth factor-stimulated PC12 cells generally differed, although there was some overlapping. Our findings provide new information about recycling endosome markers, and they highlight the heterogeneity of recycling endosomes.

  9. Homosexual, gay, and lesbian: defining the words and sampling the populations.

    Science.gov (United States)

    Donovan, J M

    1992-01-01

    The lack of both specificity and consensus about definitions for homosexual, homosexuality, gay, and lesbian are first shown to confound comparative research and cumulative understanding because criteria for inclusion within the subject populations are often not consistent. The Description section examines sociolinguistic variables which determine patterns of preferred choice of terminology, and considers how these might impact gay and lesbian studies. Attitudes and style are found to influence word choice. These results are used in the second section to devise recommended definitional limits which would satisfy both communication needs and methodological purposes, especially those of sampling.

  10. Recombinant vitronectin is a functionally defined substrate that supports human embryonic stem cell self-renewal via alphavbeta5 integrin.

    NARCIS (Netherlands)

    Braam, S.R.; Zeinstra, L.M.; Litjens, S.H.M.; Ward-van Oostwaard, D.; van den Brink, S.; van Laake, L.W.; Lebrin, F.; Kats, P.; Hochstenbach, R.; Passier, R.; Sonnenberg, A.; Mummery, C.L.

    2008-01-01

    Defined growth conditions are essential for many applications of human embryonic stem cells (hESC). Most defined media are presently used in combination with Matrigel, a partially defined extracellular matrix (ECM) extract from mouse sarcoma. Here, we defined ECM requirements of hESC by analyzing

  11. Characteristics of martial art injuries in a defined Canadian population: a descriptive epidemiological study

    Directory of Open Access Journals (Sweden)

    Pickett William

    2010-12-01

    Full Text Available Abstract Background The martial arts have emerged as common activities in the Canadian population, yet few studies have investigated the occurrence of associated injuries on a population basis. Methods We performed such an investigation and suggest potential opportunities for prevention. The data source was 14 years (1993 to 2006 of records from the Kingston sites of the Canadian Hospital Injury Reporting and Prevention Program (CHIRPP. Results 920 cases were identified. Incidence rates were initially estimated using census data as denominators. We then imputed annual injury rates per 10000 using a range of published estimates of martial arts participation available from a national survey. Rates of injury in males and females were 2300 and 1033 per 10000 (0.3% participation and 575 and 258 per 10000 (1.2% participation. Injuries were most frequently reported in karate (33% and taekwondo (14%. The most common mechanisms of injury were falls, throws and jumps (33%. Fractures (20% were the most frequently reported type of injury and the lower limb was the most common site of injury (41%. Conclusions Results provide a foundation for potential interventions with a focus on falls, the use of weapons, participation in tournaments, as well as head and neck trauma.

  12. Characteristics of martial art injuries in a defined Canadian population: a descriptive epidemiological study.

    Science.gov (United States)

    McPherson, Mark; Pickett, William

    2010-12-30

    The martial arts have emerged as common activities in the Canadian population, yet few studies have investigated the occurrence of associated injuries on a population basis. We performed such an investigation and suggest potential opportunities for prevention. The data source was 14 years (1993 to 2006) of records from the Kingston sites of the Canadian Hospital Injury Reporting and Prevention Program (CHIRPP). 920 cases were identified. Incidence rates were initially estimated using census data as denominators. We then imputed annual injury rates per 10000 using a range of published estimates of martial arts participation available from a national survey. Rates of injury in males and females were 2300 and 1033 per 10000 (0.3% participation) and 575 and 258 per 10000 (1.2% participation). Injuries were most frequently reported in karate (33%) and taekwondo (14%). The most common mechanisms of injury were falls, throws and jumps (33%). Fractures (20%) were the most frequently reported type of injury and the lower limb was the most common site of injury (41%). Results provide a foundation for potential interventions with a focus on falls, the use of weapons, participation in tournaments, as well as head and neck trauma.

  13. Attachment, Growth, and Detachment of Human Mesenchymal Stem Cells in a Chemically Defined Medium

    Directory of Open Access Journals (Sweden)

    Denise Salzig

    2016-01-01

    Full Text Available The manufacture of human mesenchymal stem cells (hMSCs for clinical applications requires an appropriate growth surface and an optimized, preferably chemically defined medium (CDM for expansion. We investigated a new protein/peptide-free CDM that supports the adhesion, growth, and detachment of an immortalized hMSC line (hMSC-TERT as well as primary cells derived from bone marrow (bm-hMSCs and adipose tissue (ad-hMSCs. We observed the rapid attachment and spreading of hMSC-TERT cells and ad-hMSCs in CDM concomitant with the expression of integrin and actin fibers. Cell spreading was promoted by coating the growth surface with collagen type IV and fibronectin. The growth of hMSC-TERT cells was similar in CDM and serum-containing medium whereas the lag phase of bm-hMSCs was prolonged in CDM. FGF-2 or surface coating with collagen type IV promoted the growth of bm-hMSCs, but laminin had no effect. All three cell types retained their trilineage differentiation capability in CDM and were detached by several enzymes (but not collagenase in the case of hMSC-TERT cells. The medium and coating did not affect detachment efficiency but influenced cell survival after detachment. CDM combined with cell-specific surface coatings and/or FGF-2 supplements is therefore as effective as serum-containing medium for the manufacture of different hMSC types.

  14. Defining Tumor Cell and Immune Cell Behavior in Vivo during Pulmonary Metastasis of Breast Cancer

    Science.gov (United States)

    2015-09-01

    version of a manuscript detailing these findings in March of 2015. Following receipt of reviews our attention was placed on responding to reviewer...increased focus on this first manuscript our attention to the second major goal for this year was delayed. However, the key element of this goal...LIVM of CFP+ cell targeting cytoplast (see also Supplementary Video 8). Colours and tracking as in d. Tracked cells labelled as cell 1, 2 or 3 in

  15. Derivation of mesenchymal stromal cells from pluripotent stem cells through a neural crest lineage using small molecule compounds with defined media.

    Directory of Open Access Journals (Sweden)

    Makoto Fukuta

    Full Text Available Neural crest cells (NCCs are an embryonic migratory cell population with the ability to differentiate into a wide variety of cell types that contribute to the craniofacial skeleton, cornea, peripheral nervous system, and skin pigmentation. This ability suggests the promising role of NCCs as a source for cell-based therapy. Although several methods have been used to induce human NCCs (hNCCs from human pluripotent stem cells (hPSCs, such as embryonic stem cells (ESCs and induced pluripotent stem cells (iPSCs, further modifications are required to improve the robustness, efficacy, and simplicity of these methods. Chemically defined medium (CDM was used as the basal medium in the induction and maintenance steps. By optimizing the culture conditions, the combination of the GSK3β inhibitor and TGFβ inhibitor with a minimum growth factor (insulin very efficiently induced hNCCs (70-80% from hPSCs. The induced hNCCs expressed cranial NCC-related genes and stably proliferated in CDM supplemented with EGF and FGF2 up to at least 10 passages without changes being observed in the major gene expression profiles. Differentiation properties were confirmed for peripheral neurons, glia, melanocytes, and corneal endothelial cells. In addition, cells with differentiation characteristics similar to multipotent mesenchymal stromal cells (MSCs were induced from hNCCs using CDM specific for human MSCs. Our simple and robust induction protocol using small molecule compounds with defined media enabled the generation of hNCCs as an intermediate material producing terminally differentiated cells for cell-based innovative medicine.

  16. Drosophila Wnt and STAT Define Apoptosis-Resistant Epithelial Cells for Tissue Regeneration after Irradiation.

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    Shilpi Verghese

    2016-09-01

    Full Text Available Drosophila melanogaster larvae irradiated with doses of ionizing radiation (IR that kill about half of the cells in larval imaginal discs still develop into viable adults. How surviving cells compensate for IR-induced cell death to produce organs of normal size and appearance remains an active area of investigation. We have identified a subpopulation of cells within the continuous epithelium of Drosophila larval wing discs that shows intrinsic resistance to IR- and drug-induced apoptosis. These cells reside in domains of high Wingless (Wg, Drosophila Wnt-1 and STAT92E (sole Drosophila signal transducer and activator of transcription [STAT] homolog activity and would normally form the hinge in the adult fly. Resistance to IR-induced apoptosis requires STAT and Wg and is mediated by transcriptional repression of the pro-apoptotic gene reaper. Lineage tracing experiments show that, following irradiation, apoptosis-resistant cells lose their identity and translocate to areas of the wing disc that suffered abundant cell death. Our findings provide a new paradigm for regeneration in which it is unnecessary to invoke special damage-resistant cell types such as stem cells. Instead, differences in gene expression within a population of genetically identical epithelial cells can create a subpopulation with greater resistance, which, following damage, survive, alter their fate, and help regenerate the tissue.

  17. Development of novel monoclonal antibodies that define differentiation stages of human stromal (mesenchymal) stem cells

    DEFF Research Database (Denmark)

    Andersen, Ditte Caroline; Kortesidis, Angela; Zannettino, Andrew C W

    2011-01-01

    Human mesenchymal stem cells (hMSC) are currently being introduced for cell therapy, yet, antibodies specific for native and differentiated MSCs are required for their identification prior to clinical use. Herein, high quality antibodies against MSC surface proteins were developed by immunizing...... fewer differentiated alkaline phosphatase(+) cells compared to STRO-1(+/-)/Collagen VI(+) hMSC, suggesting that Collagen VI on the cell membrane exclusively defines differentiated MSCs. In conclusion, we have generated a panel of high quality antibodies to be used for characterization of MSCs...... mice with hMSC, and by using a panel of subsequent screening methods. Flow cytometry analysis revealed that 83.5, 1.1, and 8.5% of primary cultures of hMSC were double positive for STRO-1 and either of DJ 3, 9, and 18, respectively. However, none of the three DJ antibodies allowed enrichment...

  18. Survival-associated heterogeneity of marker-defined perivascular cells in colorectal cancer

    DEFF Research Database (Denmark)

    Mezheyeuski, Artur; Lindh, Maja Bradic; Guren, Tormod Kyrre

    2016-01-01

    of vessel characteristics and PC, which was applied to two collections of human metastatic colorectal cancer (mCRC).Initial analyses identified marker-defined subsets of PC, including cells expressing PDGFR-β or α-SMA or both markers. PC subsets were largely independently expressed in a manner unrelated......Perivascular cells (PC) were recently implied as regulators of metastasis and immune cell activity. Perivascular heterogeneity in clinical samples, and associations with other tumor features and outcome, remain largely unknown.Here we report a novel method for digital quantitative analyses...... to vessel density and size. Association studies implied specific oncogenic mutations in malignant cells as determinants of PC status. Semi-quantitative and digital-image-analyses-based scoring of the NORDIC-VII cohort identified significant associations between low expression of perivascular PDGFR-α and -β...

  19. Defining the expression of marker genes in equine mesenchymal stromal cells

    Directory of Open Access Journals (Sweden)

    Deborah J Guest

    2008-11-01

    Full Text Available Deborah J Guest1, Jennifer C Ousey1, Matthew RW Smith21Animal Health Trust, Lanwades Park, Kentford, Newmarket, Suffolk, CB8 7UU; 2Reynolds House Referrals, Greenwood Ellis and Partners, 166 High Street, Newmarket, Suffolk, CB8 9WS, UKAbstract: Mesenchymal stromal (MS cells have been derived from multiple sources in the horse including bone marrow, adipose tissue and umbilical cord blood. To date these cells have been investigated for their differentiation potential and are currently being used to treat damage to horse musculoskeletal tissues. However, no work has been done in horse MS cells to examine the expression profile of proteins and cell surface antigens that are expressed in human MS cells. The identification of such profiles in the horse will allow the comparison of putative MS cells isolated from different laboratories and different tissues. At present it is difficult to ascertain whether equivalent cells are being used in different reports. Here, we report on the expression of a range of markers used to define human MS cells. Using immunocytochemistry we show that horse MS cells homogenously express collagens, alkaline phosphatase activity, CD44, CD90 and CD29. In contrast, CD14, CD79α and the embryonic stem cell markers Oct-4, SSEA (stage specific embryonic antigen -1, -3, -4, TRA (tumor rejection antigen -1–60 and -1–81 are not expressed. The MS cells also express MHC class I antigens but do not express class II antigens, although they are inducible by treatment with interferon gamma (IFN-γ.Keywords: mesenchymal stem cells, equine, gene expression

  20. Creation of defined single cell resolution neuronal circuits on microelectrode arrays

    Science.gov (United States)

    Pirlo, Russell Kirk

    2009-12-01

    The way cell-cell organization of neuronal networks influences activity and facilitates function is not well understood. Microelectrode arrays (MEAs) and advancing cell patterning technologies have enabled access to and control of in vitro neuronal networks spawning much new research in neuroscience and neuroengineering. We propose that small, simple networks of neurons with defined circuitry may serve as valuable research models where every connection can be analyzed, controlled and manipulated. Towards the goal of creating such neuronal networks we have applied microfabricated elastomeric membranes, surface modification and our unique laser cell patterning system to create defined neuronal circuits with single-cell precision on MEAs. Definition of synaptic connectivity was imposed by the 3D physical constraints of polydimethylsiloxane elastomeric membranes. The membranes had 20mum clear-through holes and 2-3mum deep channels which when applied to the surface of the MEA formed microwells to confine neurons to electrodes connected via shallow tunnels to direct neurite outgrowth. Tapering and turning of channels was used to influence neurite polarity. Biocompatibility of the membranes was increased by vacuum baking, oligomer extraction, and autoclaving. Membranes were bound to the MEA by oxygen plasma treatment and heated pressure. The MEA/membrane surface was treated with oxygen plasma, poly-D-lysine and laminin to improve neuron attachment, survival and neurite outgrowth. Prior to cell patterning the outer edge of culture area was seeded with 5x10 5 cells per cm and incubated for 2 days. Single embryonic day 7 chick forebrain neurons were then patterned into the microwells and onto the electrodes using our laser cell patterning system. Patterned neurons successfully attached to and were confined to the electrodes. Neurites extended through the interconnecting channels and connected with adjacent neurons. These results demonstrate that neuronal circuits can be

  1. Defining a BMI Cut-Off Point for the Iranian Population: The Shiraz Heart Study.

    Directory of Open Access Journals (Sweden)

    Mohammad Ali Babai

    Full Text Available In this study we evaluated and redefined the optimum body mass index (BMI cut-off point for the Iranian population based on metabolic syndrome (MeS risk factors. We further evaluated BMI cut-off points with and without waist circumference (WC as a cofactor of risk and compared the differences. This study is part of the largest surveillance programs conducted in Shiraz, Iran, termed the Shiraz Heart study. Our study sample included subjects between the ages of 20 to 65 years old. After excluding pregnant women, those with missing data and those with comorbid disease, a total of 12283 made up the study population. The participants underwent a series of tests and evaluations by trained professionals in accordance with WHO recommendations. Hypertension, abnormal fasting blood sugar (FBS, triglyceride (TG and high density lipoprotein cholesterol (HDL (in the context of the definition of metabolic syndrome were prevalent among 32.4%, 27.6%, 42.1 and 44.2% of our participants, respectively. Women displayed higher rates of overall obesity compared to men (based on the definition by the WHO as higher than 30 kg/m2. Regarding MeS, 38.9% of our population had the all symptoms of MeS which was more prevalent among women (41.5% vs. 36%. When excluding WC in the definition of MeS, results showed that males tend to show a higher rate of metabolic risk factors (19.2% vs. 15.6%. Results of multivariate analysis showed that parallel to an increase in BMI, the odds ratio (OR for acquiring each component of the metabolic syndrome increased (OR = 1.178; CI: 1.166-1.190. By excluding WC, the previous OR decreased (OR = 1.105; CI: 1.093-1.118. Receiver Operating Characteristic (ROC curve analysis showed that the optimum BMI cut-off point for predicting metabolic syndrome was 26.1 kg/m2 and 26.2 kg/m2 [Accuracy (Acc = 69% and 61%, respectively] for males and females, respectively. The overall BMI cut-off for both sexes was 26.2 kg/m2 (Acc = 65% with sensitivity and

  2. Endothelial Cells Control Pancreatic Cell Fate at Defined Stages through EGFL7 Signaling

    Directory of Open Access Journals (Sweden)

    Der-I Kao

    2015-02-01

    Full Text Available Although endothelial cells have been shown to affect mouse pancreatic development, their precise function in human development remains unclear. Using a coculture system containing human embryonic stem cell (hESC-derived progenitors and endothelial cells, we found that endothelial cells play a stage-dependent role in pancreatic development, in which they maintain pancreatic progenitor (PP self-renewal and impair further differentiation into hormone-expressing cells. The mechanistic studies suggest that the endothelial cells act through the secretion of EGFL7. Consistently, endothelial overexpression of EGFL7 in vivo using a transgenic mouse model resulted in an increase of PP proliferation rate and a decrease of differentiation toward endocrine cells. These studies not only identified the role of EGFL7 as the molecular handle involved in the crosstalk between endothelium and pancreatic epithelium, but also provide a paradigm for using hESC stepwise differentiation to dissect the stage-dependent roles of signals controlling organogenesis.

  3. Ecological distribution and population physiology defined by proteomics in a natural microbial community

    Science.gov (United States)

    Mueller, Ryan S.; Denef, Vincent J.; Kalnejais, Linda H.; Suttle, K. Blake; Thomas, Brian C.; Wilmes, Paul; Smith, Richard L.; Nordstrom, D. Kirk; McCleskey, R. Blaine; Shah, Menesh B.; VerBekmoes, Nathan C.; Hettich, Robert L.; Banfield, Jillian F.

    2010-01-01

    An important challenge in microbial ecology is developing methods that simultaneously examine the physiology of organisms at the molecular level and their ecosystem level interactions in complex natural systems. We integrated extensive proteomic, geochemical, and biological information from 28 microbial communities collected from an acid mine drainage environment and representing a range of biofilm development stages and geochemical conditions to evaluate how the physiologies of the dominant and less abundant organisms change along environmental gradients. The initial colonist dominates across all environments, but its proteome changes between two stable states as communities diversify, implying that interspecies interactions affect this organism's metabolism. Its overall physiology is robust to abiotic environmental factors, but strong correlations exist between these factors and certain subsets of proteins, possibly accounting for its wide environmental distribution. Lower abundance populations are patchier in their distribution, and proteomic data indicate that their environmental niches may be constrained by specific sets of abiotic environmental factors. This research establishes an effective strategy to investigate ecological relationships between microbial physiology and the environment for whole communities in situ.

  4. Ten-year detection rate of brain arteriovenous malformations in a large, multiethnic, defined population.

    Science.gov (United States)

    Gabriel, Rodney A; Kim, Helen; Sidney, Stephen; McCulloch, Charles E; Singh, Vineeta; Johnston, S Claiborne; Ko, Nerissa U; Achrol, Achal S; Zaroff, Jonathan G; Young, William L

    2010-01-01

    To evaluate whether increased neuroimaging use is associated with increased brain arteriovenous malformation (BAVM) detection, we examined detection rates in the Kaiser Permanente Medical Care Program of northern California between 1995 and 2004. We reviewed medical records, radiology reports, and administrative databases to identify BAVMs, intracranial aneurysms (IAs: subarachnoid hemorrhage [SAH] and unruptured aneurysms), and other vascular malformations (OVMs: dural fistulas, cavernous malformations, Vein of Galen malformations, and venous malformations). Poisson regression (with robust standard errors) was used to test for trend. Random-effects meta-analysis generated a pooled measure of BAVM detection rate from 6 studies. We identified 401 BAVMs (197 ruptured, 204 unruptured), 570 OVMs, and 2892 IAs (2079 SAHs and 813 unruptured IAs). Detection rates per 100 000 person-years were 1.4 (95% CI, 1.3 to 1.6) for BAVMs, 2.0 (95% CI, 1.8 to 2.3) for OVMs, and 10.3 (95% CI, 9.9 to 10.7) for IAs. Neuroimaging utilization increased 12% per year during the time period (PIAs (PIAs (P4) per 100 000 person-years, without heterogeneity between studies (P=0.25). Rates for BAVMs, OVMs, and IAs in this large, multiethnic population were similar to those in other series. During 1995 to 2004, a period of increasing neuroimaging utilization, we did not observe an increased rate of detection of unruptured BAVMs, despite increased detection of unruptured IAs.

  5. Culture conditions defining glioblastoma cells behavior: what is the impact for novel discoveries?

    Science.gov (United States)

    Ledur, Pítia Flores; Onzi, Giovana Ravizzoni; Zong, Hui; Lenz, Guido

    2017-09-15

    In cancer research, the use of established cell lines has gradually been replaced by primary cell cultures due to their better representation of in vivo cancer cell behaviors. However, a major challenge with primary culture involves the finding of growth conditions that minimize alterations in the biological state of the cells. To ensure reproducibility and translational potentials for research findings, culture conditions need to be chosen so that the cell population in culture best mimics tumor cells in vivo . Glioblastoma (GBM) is one of the most aggressive and heterogeneous tumor types and the GBM research field would certainly benefit from culture conditions that could maintain the original plethora of phenotype of the cells. Here, we review culture media and supplementation options for GBM cultures, the rationale behind their use, and how much those choices affect drug-screening outcomes. We provide an overview of 120 papers that use primary GBM cultures and discuss the current predominant conditions. We also show important primary research data indicating that "mis-cultured" glioma cells can acquire unnatural drug sensitivity, which would have devastating effects for clinical translations. Finally, we propose the concurrent test of four culture conditions to minimize the loss of cell coverage in culture.

  6. Single-Cell Transcriptomic Analysis Defines Heterogeneity and Transcriptional Dynamics in the Adult Neural Stem Cell Lineage

    Directory of Open Access Journals (Sweden)

    Ben W. Dulken

    2017-01-01

    Full Text Available Neural stem cells (NSCs in the adult mammalian brain serve as a reservoir for the generation of new neurons, oligodendrocytes, and astrocytes. Here, we use single-cell RNA sequencing to characterize adult NSC populations and examine the molecular identities and heterogeneity of in vivo NSC populations. We find that cells in the NSC lineage exist on a continuum through the processes of activation and differentiation. Interestingly, rare intermediate states with distinct molecular profiles can be identified and experimentally validated, and our analysis identifies putative surface markers and key intracellular regulators for these subpopulations of NSCs. Finally, using the power of single-cell profiling, we conduct a meta-analysis to compare in vivo NSCs and in vitro cultures, distinct fluorescence-activated cell sorting strategies, and different neurogenic niches. These data provide a resource for the field and contribute to an integrative understanding of the adult NSC lineage.

  7. Defining new criteria for selection of cell-based intestinal models using publicly available databases

    Directory of Open Access Journals (Sweden)

    Christensen Jon

    2012-06-01

    Full Text Available Abstract Background The criteria for choosing relevant cell lines among a vast panel of available intestinal-derived lines exhibiting a wide range of functional properties are still ill-defined. The objective of this study was, therefore, to establish objective criteria for choosing relevant cell lines to assess their appropriateness as tumor models as well as for drug absorption studies. Results We made use of publicly available expression signatures and cell based functional assays to delineate differences between various intestinal colon carcinoma cell lines and normal intestinal epithelium. We have compared a panel of intestinal cell lines with patient-derived normal and tumor epithelium and classified them according to traits relating to oncogenic pathway activity, epithelial-mesenchymal transition (EMT and stemness, migratory properties, proliferative activity, transporter expression profiles and chemosensitivity. For example, SW480 represent an EMT-high, migratory phenotype and scored highest in terms of signatures associated to worse overall survival and higher risk of recurrence based on patient derived databases. On the other hand, differentiated HT29 and T84 cells showed gene expression patterns closest to tumor bulk derived cells. Regarding drug absorption, we confirmed that differentiated Caco-2 cells are the model of choice for active uptake studies in the small intestine. Regarding chemosensitivity we were unable to confirm a recently proposed association of chemo-resistance with EMT traits. However, a novel signature was identified through mining of NCI60 GI50 values that allowed to rank the panel of intestinal cell lines according to their drug responsiveness to commonly used chemotherapeutics. Conclusions This study presents a straightforward strategy to exploit publicly available gene expression data to guide the choice of cell-based models. While this approach does not overcome the major limitations of such models

  8. MicroRNAs define distinct human neuroblastoma cell phenotypes and regulate their differentiation and tumorigenicity

    International Nuclear Information System (INIS)

    Samaraweera, Leleesha; Grandinetti, Kathryn B; Huang, Ruojun; Spengler, Barbara A; Ross, Robert A

    2014-01-01

    Neuroblastoma (NB) is the most common extracranial solid tumor in children. NB tumors and derived cell lines are phenotypically heterogeneous. Cell lines are classified by phenotype, each having distinct differentiation and tumorigenic properties. The neuroblastic phenotype is tumorigenic, has neuronal features and includes stem cells (I-cells) and neuronal cells (N-cells). The non-neuronal phenotype (S-cell) comprises cells that are non-tumorigenic with features of glial/smooth muscle precursor cells. This study identified miRNAs associated with each distinct cell phenotypes and investigated their role in regulating associated differentiation and tumorigenic properties. A miRNA microarray was performed on the three cell phenotypes and expression verified by qRT-PCR. miRNAs specific for certain cell phenotypes were modulated using miRNA inhibitors or stable transfection. Neuronal differentiation was induced by RA; non-neuronal differentiation by BrdU. Changes in tumorigenicity were assayed by soft agar colony forming ability. N-myc binding to miR-375 promoter was assayed by chromatin-immunoprecipitation. Unsupervised hierarchical clustering of miRNA microarray data segregated neuroblastic and non-neuronal cell lines and showed that specific miRNAs define each phenotype. qRT-PCR validation confirmed that increased levels of miR-21, miR-221 and miR-335 are associated with the non-neuronal phenotype, whereas increased levels of miR-124 and miR-375 are exclusive to neuroblastic cells. Downregulation of miR-335 in non-neuronal cells modulates expression levels of HAND1 and JAG1, known modulators of neuronal differentiation. Overexpression of miR-124 in stem cells induces terminal neuronal differentiation with reduced malignancy. Expression of miR-375 is exclusive for N-myc-expressing neuroblastic cells and is regulated by N-myc. Moreover, miR-375 downregulates expression of the neuronal-specific RNA binding protein HuD. Thus, miRNAs define distinct NB cell phenotypes

  9. Defining Population Health Vulnerability Following an Extreme Weather Event in an Urban Pacific Island Environment: Honiara, Solomon Islands

    Science.gov (United States)

    Natuzzi, Eileen S.; Joshua, Cynthia; Shortus, Matthew; Reubin, Reginald; Dalipanda, Tenneth; Ferran, Karen; Aumua, Audrey; Brodine, Stephanie

    2016-01-01

    Extreme weather events are common and increasing in intensity in the southwestern Pacific region. Health impacts from cyclones and tropical storms cause acute injuries and infectious disease outbreaks. Defining population vulnerability to extreme weather events by examining a recent flood in Honiara, Solomon Islands, can help stakeholders and policymakers adapt development to reduce future threats. The acute and subacute health impacts following the April 2014 floods were defined using data obtained from hospitals and clinics, the Ministry of Health and in-country World Health Organization office in Honiara. Geographical information system (GIS) was used to assess morbidity and mortality, and vulnerability of the health system infrastructure and households in Honiara. The April flash floods were responsible for 21 acute deaths, 33 injuries, and a diarrhea outbreak that affected 8,584 people with 10 pediatric deaths. A GIS vulnerability assessment of the location of the health system infrastructure and households relative to rivers and the coastline identified 75% of the health infrastructure and over 29% of Honiara's population as vulnerable to future hydrological events. Honiara, Solomon Islands, is a rapidly growing, highly vulnerable urban Pacific Island environment. Evaluation of the mortality and morbidity from the April 2014 floods as well as the infectious disease outbreaks that followed allows public health specialists and policy makers to understand the health system and populations vulnerability to future shocks. Understanding the negative impacts natural disaster have on people living in urban Pacific environments will help the government as well as development partners in crafting resilient adaptation development. PMID:27091867

  10. Approaches for cytogenetic and molecular analyses of small flow-sorted cell populations from childhood leukemia bone marrow samples

    DEFF Research Database (Denmark)

    Obro, Nina Friesgaard; Madsen, Hans O.; Ryder, Lars Peter

    2011-01-01

    defined cell populations with subsequent analyses of leukemia-associated cytogenetic and molecular marker. The approaches described here optimize the use of the same tube of unfixed, antibody-stained BM cells for flow-sorting of small cell populations and subsequent exploratory FISH and PCR-based analyses....

  11. The Stem Cell Marker Lgr5 Defines a Subset of Postmitotic Neurons in the Olfactory Bulb.

    Science.gov (United States)

    Yu, Yiqun; Moberly, Andrew H; Bhattarai, Janardhan P; Duan, Chen; Zheng, Qian; Li, Fangqi; Huang, Hugh; Olson, William; Luo, Wenqin; Wen, Tieqiao; Yu, Hongmeng; Ma, Minghong

    2017-09-27

    Lgr5, leucine-rich repeat-containing G-protein coupled receptor 5, is a bona fide biomarker for stem cells in multiple tissues. Lgr5 is also expressed in the brain, but the identities and properties of these Lgr5 + cells are still elusive. Using an Lgr5-EGFP reporter mouse line, we found that, from early development to adulthood, Lgr5 is highly expressed in the olfactory bulb (OB), an area with ongoing neurogenesis. Immunostaining with stem cell, glial, and neuronal markers reveals that Lgr5 does not label stem cells in the OB but instead labels a heterogeneous population of neurons with preference in certain subtypes. Patch-clamp recordings in OB slices reveal that Lgr5-EGFP + cells fire action potentials and display spontaneous excitatory postsynaptic events, indicating that these neurons are integrated into OB circuits. Interestingly, R-spondin 3, a potential ligand of Lgr5, is also expressed in the adult OB. Collectively, our data indicate that Lgr5-expressing cells in the OB are fully differentiated neurons and imply distinct roles of Lgr5 and its ligand in postmitotic cells. SIGNIFICANCE STATEMENT Lgr5 (leucine-rich repeat-containing G-protein coupled receptor 5) is a bona fide stem cell marker in many body organs. Here we report that Lgr5 is also highly expressed in the olfactory bulb (OB), the first relay station in the brain for processing odor information and one of the few neural structures that undergo continuous neurogenesis. Surprisingly, Lgr5 is not expressed in the OB stem cells, but instead in a few subtypes of terminally differentiated neurons, which are incorporated into the OB circuit. This study reveals that Lgr5 + cells in the brain represent a nonstem cell lineage, implying distinct roles of Lgr5 in postmitotic neurons. Copyright © 2017 the authors 0270-6474/17/379403-12$15.00/0.

  12. Three distinct subsets of thymic epithelial cells in rats and mice defined by novel antibodies.

    Directory of Open Access Journals (Sweden)

    Yasushi Sawanobori

    Full Text Available Thymic epithelial cells (TECs are thought to play an essential role in T cell development and have been detected mainly in mice using lectin binding and antibodies to keratins. Our aim in the present study was to create a precise map of rat TECs using antibodies to putative markers and novel monoclonal antibodies (i.e., ED 18/19/21 and anti-CD205 antibodies and compare it with a map from mouse counterparts and that of rat thymic dendritic cells.Rat TECs were subdivided on the basis of phenotype into three subsets; ED18+ED19+/-keratin 5 (K5+K8+CD205+ class II MHC (MHCII+ cortical TECs (cTECs, ED18+ED21-K5-K8+Ulex europaeus lectin 1 (UEA-1+CD205- medullary TECs (mTEC1s, and ED18+ED21+K5+K8dullUEA-1-CD205- medullary TECs (mTEC2s. Thymic nurse cells were defined in cytosmears as an ED18+ED19+/-K5+K8+ subset of cTECs. mTEC1s preferentially expressed MHCII, claudin-3, claudin-4, and autoimmune regulator (AIRE. Use of ED18 and ED21 antibodies revealed three subsets of TECs in mice as well. We also detected two distinct TEC-free areas in the subcapsular cortex and in the medulla. Rat dendritic cells in the cortex were MHCII+CD103+ but negative for TEC markers, including CD205. Those in the medulla were MHCII+CD103+ and CD205+ cells were found only in the TEC-free area.Both rats and mice have three TEC subsets with similar phenotypes that can be identified using known markers and new monoclonal antibodies. These findings will facilitate further analysis of TEC subsets and DCs and help to define their roles in thymic selection and in pathological states such as autoimmune disorders.

  13. Any Defining Role of Mast Cell or Mast Cell Density in Oral ...

    African Journals Online (AJOL)

    in the pathophysiology of the host reaction, for example, in early gastric or breast cancer. ... mechanisms plus its importance are not clarified. Noticeably, most of the ... renal cancer, even with non-small cell lung carcinomas.[6,7,16-18]. Letter to ...

  14. The mother centriole plays an instructive role in defining cell geometry.

    Directory of Open Access Journals (Sweden)

    Jessica L Feldman

    2007-06-01

    Full Text Available Centriole positioning is a key step in establishment and propagation of cell geometry, but the mechanism of this positioning is unknown. The ability of pre-existing centrioles to induce formation of new centrioles at a defined angle relative to themselves suggests they may have the capacity to transmit spatial information to their daughters. Using three-dimensional computer-aided analysis of cell morphology in Chlamydomonas, we identify six genes required for centriole positioning relative to overall cell polarity, four of which have known sequences. We show that the distal portion of the centriole is critical for positioning, and that the centriole positions the nucleus rather than vice versa. We obtain evidence that the daughter centriole is unable to respond to normal positioning cues and relies on the mother for positional information. Our results represent a clear example of "cytotaxis" as defined by Sonneborn, and suggest that centrioles can play a key function in propagation of cellular geometry from one generation to the next. The genes documented here that are required for proper centriole positioning may represent a new class of ciliary disease genes, defects in which would be expected to cause disorganized ciliary position and impaired function.

  15. Microfluidic perfusion culture of human induced pluripotent stem cells under fully defined culture conditions.

    Science.gov (United States)

    Yoshimitsu, Ryosuke; Hattori, Koji; Sugiura, Shinji; Kondo, Yuki; Yamada, Rotaro; Tachikawa, Saoko; Satoh, Taku; Kurisaki, Akira; Ohnuma, Kiyoshi; Asashima, Makoto; Kanamori, Toshiyuki

    2014-05-01

    Human induced pluripotent stem cells (hiPSCs) are a promising cell source for drug screening. For this application, self-renewal or differentiation of the cells is required, and undefined factors in the culture conditions are not desirable. Microfluidic perfusion culture allows the production of small volume cultures with precisely controlled microenvironments, and is applicable to high-throughput cellular environment screening. Here, we developed a microfluidic perfusion culture system for hiPSCs that uses a microchamber array chip under defined extracellular matrix (ECM) and culture medium conditions. By screening various ECMs we determined that fibronectin and laminin are appropriate for microfluidic devices made out of the most popular material, polydimethylsiloxane (PDMS). We found that the growth rate of hiPSCs under pressure-driven perfusion culture conditions was higher than under static culture conditions in the microchamber array. We applied our new system to self-renewal and differentiation cultures of hiPSCs, and immunocytochemical analysis showed that the state of the hiPSCs was successfully controlled. The effects of three antitumor drugs on hiPSCs were comparable between microchamber array and 96-well plates. We believe that our system will be a platform technology for future large-scale screening of fully defined conditions for differentiation cultures on integrated microfluidic devices. © 2013 Wiley Periodicals, Inc.

  16. The fast-recycling receptor Megalin defines the apical recycling pathway of epithelial cells

    Science.gov (United States)

    Perez Bay, Andres E.; Schreiner, Ryan; Benedicto, Ignacio; Paz Marzolo, Maria; Banfelder, Jason; Weinstein, Alan M.; Rodriguez-Boulan, Enrique J.

    2016-01-01

    The basolateral recycling and transcytotic pathways of epithelial cells were previously defined using markers such as transferrin (TfR) and polymeric IgA (pIgR) receptors. In contrast, our knowledge of the apical recycling pathway remains fragmentary. Here we utilize quantitative live-imaging and mathematical modelling to outline the recycling pathway of Megalin (LRP-2), an apical receptor with key developmental and renal functions, in MDCK cells. We show that, like TfR, Megalin is a long-lived and fast-recycling receptor. Megalin enters polarized MDCK cells through segregated apical sorting endosomes and subsequently intersects the TfR and pIgR pathways at a perinuclear Rab11-negative compartment termed common recycling endosomes (CRE). Whereas TfR recycles to the basolateral membrane from CRE, Megalin, like pIgR, traffics to subapical Rab11-positive apical recycling endosomes (ARE) and reaches the apical membrane in a microtubule- and Rab11-dependent manner. Hence, Megalin defines the apical recycling pathway of epithelia, with CRE as its apical sorting station. PMID:27180806

  17. An imbalance in progenitor cell populations reflects tumour progression in breast cancer primary culture models.

    LENUS (Irish Health Repository)

    Donatello, Simona

    2011-01-01

    Many factors influence breast cancer progression, including the ability of progenitor cells to sustain or increase net tumour cell numbers. Our aim was to define whether alterations in putative progenitor populations could predict clinicopathological factors of prognostic importance for cancer progression.

  18. Anatomical and molecular consequences of Unilateral Naris Closure on two populations of olfactory sensory neurons expressing defined odorant receptors.

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    Molinas, Adrien; Aoudé, Imad; Soubeyre, Vanessa; Tazir, Bassim; Cadiou, Hervé; Grosmaitre, Xavier

    2016-07-28

    Mammalian olfactory sensory neurons (OSNs), the primary elements of the olfactory system, are located in the olfactory epithelium lining the nasal cavity. Exposed to the environment, their lifespan is short. Consequently, OSNs are regularly regenerated and several reports show that activity strongly modulates their development and regeneration: the peripheral olfactory system can adjust to the amount of stimulus through compensatory mechanisms. Unilateral naris occlusion (UNO) was frequently used to investigate this mechanism at the entire epithelium level. However, there is little data regarding the effects of UNO at the cellular level, especially on individual neuronal populations expressing a defined odorant receptor. Here, using UNO during the first three postnatal weeks, we analyzed the anatomical and molecular consequences of sensory deprivation in OSNs populations expressing the MOR23 and M71 receptors. The density of MOR23-expressing neurons is decreased in the closed side while UNO does not affect the density of M71-expressing neurons. Using Real Time qPCR on isolated neurons, we observed that UNO modulates the transcript levels for transduction pathway proteins (odorant receptors, CNGA2, PDE1c). The transcripts modulated by UNO will differ between populations depending on the receptor expressed. These results suggest that sensory deprivation will have different effects on different OSNs' populations. As a consequence, early experience will shape the functional properties of OSNs differently depending on the type of odorant receptor they express. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

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

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    Giorgia Salvagiotto

    2011-03-01

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

  20. Laminin enhances the growth of human neural stem cells in defined culture media

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    Lathia Justin D

    2008-07-01

    Full Text Available Abstract Background Human neural stem cells (hNSC have the potential to provide novel cell-based therapies for neurodegenerative conditions such as multiple sclerosis and Parkinson's disease. In order to realise this goal, protocols need to be developed that allow for large quantities of hNSC to be cultured efficiently. As such, it is important to identify factors which enhance the growth of hNSC. In vivo, stem cells reside in distinct microenvironments or niches that are responsible for the maintenance of stem cell populations. A common feature of niches is the presence of the extracellular matrix molecule, laminin. Therefore, this study investigated the effect of exogenous laminin on hNSC growth. Results To measure hNSC growth, we established culture conditions using B27-supplemented medium that enable neurospheres to grow from human neural cells plated at clonal densities. Limiting dilution assays confirmed that neurospheres were derived from single cells at these densities. Laminin was found to increase hNSC numbers as measured by this neurosphere formation. The effect of laminin was to augment the proliferation/survival of the hNSC, rather than promoting the undifferentiated state. In agreement, apoptosis was reduced in dissociated neurospheres by laminin in an integrin β1-dependent manner. Conclusion The addition of laminin to the culture medium enhances the growth of hNSC, and may therefore aid their large-scale production.

  1. Scalable cultivation of human pluripotent stem cells on chemically-defined surfaces

    Science.gov (United States)

    Hsiung, Michael Chi-Wei

    Human stem cells (SCs) are classified as self-renewing cells possessing great ability in therapeutic applications due of their ability to differentiate along any major cell lineage in the human body. Despite their restorative potential, widespread use of SCs is hampered by strenuous control issues. Along with the need for strict xeno-free environments to sustain growth in culture, current methods for growing human pluripotent stem cells (hPSCs) rely on platforms which impede large-scale cultivation and therapeutic delivery. Hence, any progress towards development of large-scale culture systems is severely hindered. In a concentrated effort to develop a scheme that can serve as a model precursor for large scale SC propagation in clinical use, we have explored methods for cultivating hPSCs on completely defined surfaces. We discuss novel approaches with the potential to go beyond the limitations presented by current methods. In particular, we studied the cultivation of human embryonic stem cells (hESCs) and human induced pluripotent stem cells (hiPSCs) on surface which underwent synthetic or chemical modification. Current methods for hPSCs rely on animal-based extracellular matrices (ECMs) such as mouse embryonic fibroblasts (MEFs) or feeders and murine sacoma cell-derived substrates to facilitate their growth. While these layers or coatings can be used to maximize the output of hPSC production, they cannot be considered for clinical use because they risk introducing foreign pathogens into culture. We have identified and developed conditions for a completely defined xeno-free substrate used for culturing hPSCs. By utilizing coupling chemistry, we can functionalize ester groups on a given surface and conjugate synthetic peptides containing the arginine-glycine-aspartic acid (RGD) motif, known for their role in cell adhesion. This method offers advantages over traditional hPSC culture by keeping the modified substrata free of xenogenic response and can be scaled up in

  2. Osteogenic response of human mesenchymal stem cells to well-defined nanoscale topography in vitro

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    de Peppo GM

    2014-05-01

    Full Text Available Giuseppe Maria de Peppo,1–3 Hossein Agheli,2,3 Camilla Karlsson,2,3 Karin Ekström,2,3 Helena Brisby,3,4 Maria Lennerås,2,3 Stefan Gustafsson,3,5 Peter Sjövall,3,5,6 Anna Johansson,2,3 Eva Olsson,3,5 Jukka Lausmaa,3,6 Peter Thomsen,2,3 Sarunas Petronis3,6 1The New York Stem Cell Foundation Research Institute, New York, NY, USA; 2Department of Biomaterials, Sahlgrenska Academy, University of Gothenburg, 3BIOMATCELL VINN Excellence Center of Biomaterials and Cell Therapy, 4Department of Orthopaedics, Sahlgrenska Academy, University of Gothenburg, 5Applied Physics, Chalmers University of Technology, Göteborg, Sweden; 6Chemistry, Materials and Surfaces, SP Technical Research Institute of Sweden, Borås, Sweden Background: Patterning medical devices at the nanoscale level enables the manipulation of cell behavior and tissue regeneration, with topographic features recognized as playing a significant role in the osseointegration of implantable devices. Methods: In this study, we assessed the ability of titanium-coated hemisphere-like topographic nanostructures of different sizes (approximately 50, 100, and 200 nm to influence the morphology, proliferation, and osteogenic differentiation of human mesenchymal stem cells (hMSCs. Results: We found that the proliferation and osteogenic differentiation of hMSCs was influenced by the size of the underlying structures, suggesting that size variations in topographic features at the nanoscale level, independently of chemistry, can be exploited to control hMSC behavior in a size-dependent fashion. Conclusion: Our studies demonstrate that colloidal lithography, in combination with coating technologies, can be exploited to investigate the cell response to well defined nanoscale topography and to develop next-generation surfaces that guide tissue regeneration and promote implant integration. Keywords: colloidal lithography, nanotopography, human mesenchymal stem cells, cell proliferation, osteogenic

  3. Systematic development and optimization of chemically defined medium supporting high cell density growth of Bacillus coagulans.

    Science.gov (United States)

    Chen, Yu; Dong, Fengqing; Wang, Yonghong

    2016-09-01

    With determined components and experimental reducibility, the chemically defined medium (CDM) and the minimal chemically defined medium (MCDM) are used in many metabolism and regulation studies. This research aimed to develop the chemically defined medium supporting high cell density growth of Bacillus coagulans, which is a promising producer of lactic acid and other bio-chemicals. In this study, a systematic methodology combining the experimental technique with flux balance analysis (FBA) was proposed to design and simplify a CDM. The single omission technique and single addition technique were employed to determine the essential and stimulatory compounds, before the optimization of their concentrations by the statistical method. In addition, to improve the growth rationally, in silico omission and addition were performed by FBA based on the construction of a medium-size metabolic model of B. coagulans 36D1. Thus, CDMs were developed to obtain considerable biomass production of at least five B. coagulans strains, in which two model strains B. coagulans 36D1 and ATCC 7050 were involved.

  4. Development of Novel Monoclonal Antibodies that Define Differentiation Stages of Human Stromal (Mesenchymal) Stem Cells

    Science.gov (United States)

    Andersen, Ditte C.; Kortesidis, Angela; Zannettino, Andrew C.W.; Kratchmarova, Irina; Chen, Li; Jensen, Ole N.; Teisner, Børge; Gronthos, Stan; Jensen, Charlotte H.; Kassem, Moustapha

    2011-01-01

    Human mesenchymal stem cells (hMSC) are currently being introduced for cell therapy, yet, antibodies specific for native and differentiated MSCs are required for their identification prior to clinical use. Herein, high quality antibodies against MSC surface proteins were developed by immunizing mice with hMSC, and by using a panel of subsequent screening methods. Flow cytometry analysis revealed that 83.5, 1.1, and 8.5% of primary cultures of hMSC were double positive for STRO-1 and either of DJ 3, 9, and 18, respectively. However, none of the three DJ antibodies allowed enrichment of clonogenic hMSC from BMMNCs as single reagents. Using mass-spectrometric analysis, we identified the antigen recognised by DJ3 as CD44, whereas DJ9 and DJ18 recognized HLA-DRB1 and Collagen VI, respectively. The identified proteins were highly expressed throughout in vitro osteogenic- and adipogenic differentiation. Interestingly, undifferentiated cells revealed a sole cytoplasmic distribution pattern of Collagen VI, which however changed to an extracellular matrix appearance upon osteogenic- and adipogenic differentiation. In relation to this, we found that STRO-1+/-/Collagen VI- sorted hMSC contained fewer differentiated alkaline phosphatase + cells compared to STRO-1+/-/Collagen VI+ hMSC, suggesting that Collagen VI on the cell membrane exclusively defines differentiated MSCs. In conclusion, we have generated a panel of high quality antibodies to be used for characterization of MSCs, and in addition our results may suggest that the DJ18 generated antibody against Collagen VI can be used for negative selection of cultured undifferentiated MSCs. PMID:21614487

  5. RYBP and Cbx7 Define Specific Biological Functions of Polycomb Complexes in Mouse Embryonic Stem Cells

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    Lluis Morey

    2013-01-01

    Full Text Available The Polycomb repressive complex 1 (PRC1 is required for decisions of stem cell fate. In mouse embryonic stem cells (ESCs, two major variations of PRC1 complex, defined by the mutually exclusive presence of Cbx7 or RYBP, have been identified. Here, we show that although the genomic localization of the Cbx7- and RYBP-containing PRC1 complexes overlaps in certain genes, it can also be mutually exclusive. At the molecular level, Cbx7 is necessary for recruitment of Ring1B to chromatin, whereas RYBP enhances the PRC1 enzymatic activity. Genes occupied by RYBP show lower levels of Ring1B and H2AK119ub and are consequently more highly transcribed than those bound by Cbx7. At the functional level, we show that genes occupied by RYBP are primarily involved in the regulation of metabolism and cell-cycle progression, whereas those bound by Cbx7 predominantly control early-lineage commitment of ESCs. Altogether, our results indicate that different PRC1 subtypes establish a complex pattern of gene regulation that regulates common and nonoverlapping aspects of ESC pluripotency and differentiation.

  6. Defining constant versus variable phenotypic features of women with polycystic ovary syndrome using different ethnic groups and populations.

    Science.gov (United States)

    Welt, C K; Arason, G; Gudmundsson, J A; Adams, J; Palsdóttir, H; Gudlaugsdóttir, G; Ingadóttir, G; Crowley, W F

    2006-11-01

    The phenotype of women with polycystic ovary syndrome (PCOS) is variable, depending on the ethnic background. The phenotypes of women with PCOS in Iceland and Boston were compared. The study was observational with a parallel design. Subjects were studied in an outpatient setting. Women, aged 18-45 yr, with PCOS defined by hyperandrogenism and fewer than nine menses per year, were examined in Iceland (n = 105) and Boston (n = 262). PCOS subjects underwent a physical exam, fasting blood samples for androgens, gonadotropins, metabolic parameters, and a transvaginal ultrasound. The phenotype of women with PCOS was compared between Caucasian women in Iceland and Boston and among Caucasian, African-American, Hispanic, and Asian women in Boston. Androstenedione (4.0 +/- 1.3 vs. 3.5 +/- 1.2 ng/ml; P PCOS. There were no differences in fasting blood glucose, insulin, or homeostasis model assessment in body mass index-matched Caucasian subjects from Iceland or Boston or in different ethnic groups in Boston. Polycystic ovary morphology was demonstrated in 93-100% of women with PCOS in all ethnic groups. The data demonstrate differences in the reproductive features of PCOS without differences in glucose and insulin in body mass index-matched populations. These studies also suggest that measuring androstenedione is important for the documentation of hyperandrogenism in Icelandic women. Finally, polycystic ovary morphology by ultrasound is an almost universal finding in women with PCOS as defined by hyperandrogenism and irregular menses.

  7. Bayesian population structure analysis reveals presence of phylogeographically specific sublineages within previously ill-defined T group of Mycobacterium tuberculosis.

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    Yann Reynaud

    Full Text Available Mycobacterium tuberculosis genetic structure, and evolutionary history have been studied for years by several genotyping approaches, but delineation of a few sublineages remains controversial and needs better characterization. This is particularly the case of T group within lineage 4 (L4 which was first described using spoligotyping to pool together a number of strains with ill-defined signatures. Although T strains were not traditionally considered as a real phylogenetic group, they did contain a few phylogenetically meaningful sublineages as shown using SNPs. We therefore decided to investigate if this observation could be corroborated using other robust genetic markers. We consequently made a first assessment of genetic structure using 24-loci MIRU-VNTRs data extracted from the SITVIT2 database (n = 607 clinical isolates collected in Russia, Albania, Turkey, Iraq, Brazil and China. Combining Minimum Spanning Trees and Bayesian population structure analyses (using STRUCTURE and TESS softwares, we distinctly identified eight tentative phylogenetic groups (T1-T8 with a remarkable correlation with geographical origin. We further compared the present structure observed with other L4 sublineages (n = 416 clinical isolates belonging to LAM, Haarlem, X, S sublineages, and showed that 5 out of 8 T groups seemed phylogeographically well-defined as opposed to the remaining 3 groups that partially mixed with other L4 isolates. These results provide with novel evidence about phylogeographically specificity of a proportion of ill-defined T group of M. tuberculosis. The genetic structure observed will now be further validated on an enlarged worldwide dataset using Whole Genome Sequencing (WGS.

  8. Transfection of brain capillary endothelial cells in primary culture with defined blood-brain barrier properties.

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    Burkhart, Annette; Thomsen, Louiza Bohn; Thomsen, Maj Schneider; Lichota, Jacek; Fazakas, Csilla; Krizbai, István; Moos, Torben

    2015-08-07

    Primary brain capillary endothelial cells (BCECs) are a promising tool to study the blood-brain barrier (BBB) in vitro, as they maintain many important characteristics of the BBB in vivo, especially when co-cultured with pericytes and/or astrocytes. A novel strategy for drug delivery to the brain is to transform BCECs into protein factories by genetic modifications leading to secretion of otherwise BBB impermeable proteins into the central nervous system. However, a huge challenge underlying this strategy is to enable transfection of non-mitotic BCECs, taking a non-viral approach. We therefore aimed to study transfection in primary, non-mitotic BCECs cultured with defined BBB properties without disrupting the cells' integrity. Primary cultures of BCECs, pericytes and astrocytes were generated from rat brains and used in three different in vitro BBB experimental arrangements, which were characterised based on a their expression of tight junction proteins and other BBB specific proteins, high trans-endothelial electrical resistance (TEER), and low passive permeability to radiolabeled mannitol. Recombinant gene expression and protein synthesis were examined in primary BCECs. The BCECs were transfected using a commercially available transfection agent Turbofect™ to express the red fluorescent protein HcRed1-C1. The BCECs were transfected at different time points to monitor transfection in relation to mitotic or non-mitotic cells, as indicated by fluorescence-activated cell sorting analysis after 5-and 6-carboxylfluorescein diacetate succinidyl ester incorporation. The cell cultures exhibited important BBB characteristics judged from their expression of BBB specific proteins, high TEER values, and low passive permeability. Among the three in vitro BBB models, co-culturing with BCECs and astrocytes was well suited for the transfection studies. Transfection was independent of cell division and with equal efficacy between the mitotic and non-mitotic BCECs. Importantly

  9. Inadequate Iodine Intake in Population Groups Defined by Age, Life Stage and Vegetarian Dietary Practice in a Norwegian Convenience Sample.

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    Brantsæter, Anne Lise; Knutsen, Helle Katrine; Johansen, Nina Cathrine; Nyheim, Kristine Aastad; Erlund, Iris; Meltzer, Helle Margrete; Henjum, Sigrun

    2018-02-17

    Inadequate iodine intake has been identified in populations considered iodine replete for decades. The objective of the current study is to evaluate urinary iodine concentration (UIC) and the probability of adequate iodine intake in subgroups of the Norwegian population defined by age, life stage and vegetarian dietary practice. In a cross-sectional survey, we assessed the probability of adequate iodine intake by two 24-h food diaries and UIC from two fasting morning spot urine samples in 276 participants. The participants included children ( n = 47), adolescents ( n = 46), adults ( n = 71), the elderly ( n = 23), pregnant women ( n = 45), ovo-lacto vegetarians ( n = 25), and vegans ( n = 19). In all participants combined, the median (95% CI) UIC was 101 (90, 110) µg/L, median (25th, 75th percentile) calculated iodine intake was 112 (77, 175) µg/day and median (25th, 75th percentile) estimated usual iodine intake was 101 (75, 150) µg/day. According to WHOs criteria for evaluation of median UIC, iodine intake was inadequate in the elderly, pregnant women, vegans and non-pregnant women of childbearing age. Children had the highest (82%) and vegans the lowest (14%) probability of adequate iodine intake according to reported food and supplement intakes. This study confirms the need for monitoring iodine intake and status in nationally representative study samples in Norway.

  10. Efficient, long term production of monocyte-derived macrophages from human pluripotent stem cells under partly-defined and fully-defined conditions.

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    Bonnie van Wilgenburg

    Full Text Available Human macrophages are specialised hosts for HIV-1, dengue virus, Leishmania and Mycobacterium tuberculosis. Yet macrophage research is hampered by lack of appropriate cell models for modelling infection by these human pathogens, because available myeloid cell lines are, by definition, not terminally differentiated like tissue macrophages. We describe here a method for deriving monocytes and macrophages from human Pluripotent Stem Cells which improves on previously published protocols in that it uses entirely defined, feeder- and serum-free culture conditions and produces very consistent, pure, high yields across both human Embryonic Stem Cell (hESC and multiple human induced Pluripotent Stem Cell (hiPSC lines over time periods of up to one year. Cumulatively, up to ∼3×10(7 monocytes can be harvested per 6-well plate. The monocytes produced are most closely similar to the major blood monocyte (CD14(+, CD16(low, CD163(+. Differentiation with M-CSF produces macrophages that are highly phagocytic, HIV-1-infectable, and upon activation produce a pro-inflammatory cytokine profile similar to blood monocyte-derived macrophages. Macrophages are notoriously hard to genetically manipulate, as they recognise foreign nucleic acids; the lentivector system described here overcomes this, as pluripotent stem cells can be relatively simply genetically manipulated for efficient transgene expression in the differentiated cells, surmounting issues of transgene silencing. Overall, the method we describe here is an efficient, effective, scalable system for the reproducible production and genetic modification of human macrophages, facilitating the interrogation of human macrophage biology.

  11. Large-scale production of megakaryocytes from human pluripotent stem cells by chemically defined forward programming.

    Science.gov (United States)

    Moreau, Thomas; Evans, Amanda L; Vasquez, Louella; Tijssen, Marloes R; Yan, Ying; Trotter, Matthew W; Howard, Daniel; Colzani, Maria; Arumugam, Meera; Wu, Wing Han; Dalby, Amanda; Lampela, Riina; Bouet, Guenaelle; Hobbs, Catherine M; Pask, Dean C; Payne, Holly; Ponomaryov, Tatyana; Brill, Alexander; Soranzo, Nicole; Ouwehand, Willem H; Pedersen, Roger A; Ghevaert, Cedric

    2016-04-07

    The production of megakaryocytes (MKs)--the precursors of blood platelets--from human pluripotent stem cells (hPSCs) offers exciting clinical opportunities for transfusion medicine. Here we describe an original approach for the large-scale generation of MKs in chemically defined conditions using a forward programming strategy relying on the concurrent exogenous expression of three transcription factors: GATA1, FLI1 and TAL1. The forward programmed MKs proliferate and differentiate in culture for several months with MK purity over 90% reaching up to 2 × 10(5) mature MKs per input hPSC. Functional platelets are generated throughout the culture allowing the prospective collection of several transfusion units from as few as 1 million starting hPSCs. The high cell purity and yield achieved by MK forward programming, combined with efficient cryopreservation and good manufacturing practice (GMP)-compatible culture, make this approach eminently suitable to both in vitro production of platelets for transfusion and basic research in MK and platelet biology.

  12. Prognostic Significance of Progesterone Receptor–Positive Tumor Cells Within Immunohistochemically Defined Luminal A Breast Cancer

    Science.gov (United States)

    Prat, Aleix; Cheang, Maggie Chon U.; Martín, Miguel; Parker, Joel S.; Carrasco, Eva; Caballero, Rosalía; Tyldesley, Scott; Gelmon, Karen; Bernard, Philip S.; Nielsen, Torsten O.; Perou, Charles M.

    2013-01-01

    Purpose Current immunohistochemical (IHC)-based definitions of luminal A and B breast cancers are imperfect when compared with multigene expression-based assays. In this study, we sought to improve the IHC subtyping by examining the pathologic and gene expression characteristics of genomically defined luminal A and B subtypes. Patients and Methods Gene expression and pathologic features were collected from primary tumors across five independent cohorts: British Columbia Cancer Agency (BCCA) tamoxifen-treated only, Grupo Español de Investigación en Cáncer de Mama 9906 trial, BCCA no systemic treatment cohort, PAM50 microarray training data set, and a combined publicly available microarray data set. Optimal cutoffs of percentage of progesterone receptor (PR) –positive tumor cells to predict survival were derived and independently tested. Multivariable Cox models were used to test the prognostic significance. Results Clinicopathologic comparisons among luminal A and B subtypes consistently identified higher rates of PR positivity, human epidermal growth factor receptor 2 (HER2) negativity, and histologic grade 1 in luminal A tumors. Quantitative PR gene and protein expression were also found to be significantly higher in luminal A tumors. An empiric cutoff of more than 20% of PR-positive tumor cells was statistically chosen and proved significant for predicting survival differences within IHC-defined luminal A tumors independently of endocrine therapy administration. Finally, no additional prognostic value within hormonal receptor (HR) –positive/HER2-negative disease was observed with the use of the IHC4 score when intrinsic IHC-based subtypes were used that included the more than 20% PR-positive tumor cells and vice versa. Conclusion Semiquantitative IHC expression of PR adds prognostic value within the current IHC-based luminal A definition by improving the identification of good outcome breast cancers. The new proposed IHC-based definition of luminal A

  13. Synthetic surface for expansion of human mesenchymal stem cells in xeno-free, chemically defined culture conditions.

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    Paula J Dolley-Sonneville

    Full Text Available Human mesenchymal stem cells (HMSCS possess three properties of great interest for the development of cell therapies and tissue engineering: multilineage differentiation, immunomodulation, and production of trophic factors. Efficient ex vivo expansion of hMSCs is a challenging requirement for large scale production of clinical grade cells. Low-cost, robust, scalable culture methods using chemically defined materials need to be developed to address this need. This study describes the use of a xeno-free synthetic peptide acrylate surface, the Corning® Synthemax® Surface, for culture of hMSCs in serum-free, defined medium. Cell performance on the Corning Synthemax Surface was compared to cells cultured on biological extracellular matrix (ECM coatings in xeno-free defined medium and in traditional conditions on tissue culture treated (TCT plastic in fetal bovine serum (FBS supplemented medium. Our results show successful maintenance of hMSCs on Corning Synthemax Surface for eight passages, with cell expansion rate comparable to cells cultured on ECM and significantly higher than for cells in TCT/FBS condition. Importantly, on the Corning Synthemax Surface, cells maintained elongated, spindle-like morphology, typical hMSC marker profile and in vitro multilineage differentiation potential. We believe the Corning Synthemax Surface, in combination with defined media, provides a complete synthetic, xeno-free, cell culture system for scalable production of hMSCs.

  14. Clonal characterization of rat muscle satellite cells: proliferation, metabolism and differentiation define an intrinsic heterogeneity.

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    Carlo A Rossi

    2010-01-01

    Full Text Available Satellite cells (SCs represent a distinct lineage of myogenic progenitors responsible for the postnatal growth, repair and maintenance of skeletal muscle. Distinguished on the basis of their unique position in mature skeletal muscle, SCs were considered unipotent stem cells with the ability of generating a unique specialized phenotype. Subsequently, it was demonstrated in mice that opposite differentiation towards osteogenic and adipogenic pathways was also possible. Even though the pool of SCs is accepted as the major, and possibly the only, source of myonuclei in postnatal muscle, it is likely that SCs are not all multipotent stem cells and evidences for diversities within the myogenic compartment have been described both in vitro and in vivo. Here, by isolating single fibers from rat flexor digitorum brevis (FDB muscle we were able to identify and clonally characterize two main subpopulations of SCs: the low proliferative clones (LPC present in major proportion (approximately 75% and the high proliferative clones (HPC, present instead in minor amount (approximately 25%. LPC spontaneously generate myotubes whilst HPC differentiate into adipocytes even though they may skip the adipogenic program if co-cultured with LPC. LPC and HPC differ also for mitochondrial membrane potential (DeltaPsi(m, ATP balance and Reactive Oxygen Species (ROS generation underlying diversities in metabolism that precede differentiation. Notably, SCs heterogeneity is retained in vivo. SCs may therefore be comprised of two distinct, though not irreversibly committed, populations of cells distinguishable for prominent differences in basal biological features such as proliferation, metabolism and differentiation. By these means, novel insights on SCs heterogeneity are provided and evidences for biological readouts potentially relevant for diagnostic purposes described.

  15. Chimeric antigen receptor-modified T cells for the treatment of solid tumors: Defining the challenges and next steps☆

    OpenAIRE

    Beatty, Gregory L.; O’Hara, Mark

    2016-01-01

    Chimeric antigen receptor (CAR) T cell therapy has shown promise in CD19 expressing hematologic malignancies, but how to translate this success to solid malignancies remains elusive. Effective translation of CAR T cells to solid tumors will require an understanding of potential therapeutic barriers, including factors that regulate CAR T cells expansion, persistence, trafficking, and fate within tumors. Herein, we describe the current state of CAR T cells in solid tumors; define key barriers t...

  16. A microarray analysis of two distinct lymphatic endothelial cell populations

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    Bernhard Schweighofer

    2015-06-01

    Full Text Available We have recently identified lymphatic endothelial cells (LECs to form two morphologically different populations, exhibiting significantly different surface protein expression levels of podoplanin, a major surface marker for this cell type. In vitro shockwave treatment (IVSWT of LECs resulted in enrichment of the podoplaninhigh cell population and was accompanied by markedly increased cell proliferation, as well as 2D and 3D migration. Gene expression profiles of these distinct populations were established using Affymetrix microarray analyses. Here we provide additional details about our dataset (NCBI GEO accession number GSE62510 and describe how we analyzed the data to identify differently expressed genes in these two LEC populations.

  17. Optimization of chemically defined cell culture media--replacing fetal bovine serum in mammalian in vitro methods

    DEFF Research Database (Denmark)

    van der Valk, J; Brunner, D; De Smet, K

    2010-01-01

    with an undefined and variable composition. Defined media supplements are commercially available for some cell types. However, information on the formulation by the companies is often limited and such supplements can therefore not be regarded as completely defined. The development of defined media is difficult......, reproducible and reduce the use of experimental animals. Good cell culture practice (GCCP) is an attempt to develop a common standard for in vitro methods. The implementation of the use of chemically defined media is part of the GCCP. This will decrease the dependence on animal serum, a supplement...... and often takes place in isolation. A workshop was organised in 2009 in Copenhagen to discuss strategies to improve the development and use of serum-free defined media. In this report, the results from the meeting are discussed and the formulation of a basic serum-free medium is suggested. Furthermore...

  18. Defined spatiotemporal features of RAS-ERK signals dictate cell fate in MCF-7 mammary epithelial cells.

    Science.gov (United States)

    Herrero, Ana; Casar, Berta; Colón-Bolea, Paula; Agudo-Ibáñez, Lorena; Crespo, Piero

    2016-06-15

    Signals conveyed through the RAS-ERK pathway are essential for the determination of cell fate. It is well established that signal variability is achieved in the different microenvironments in which signals unfold. It is also known that signal duration is critical for decisions concerning cell commitment. However, it is unclear how RAS-ERK signals integrate time and space in order to elicit a given biological response. To investigate this, we used MCF-7 cells, in which EGF-induced transient ERK activation triggers proliferation, whereas sustained ERK activation in response to heregulin leads to adipocytic differentiation. We found that both proliferative and differentiating signals emanate exclusively from plasma membrane-disordered microdomains. Of interest, the EGF signal can be transformed into a differentiating stimulus by HRAS overexpression, which prolongs ERK activation, but only if HRAS localizes at disordered membrane. On the other hand, HRAS signals emanating from the Golgi complex induce apoptosis and can prevent heregulin-induced differentiation. Our results indicate that within the same cellular context, RAS can exert different, even antagonistic, effects, depending on its sublocalization. Thus cell destiny is defined by the ability of a stimulus to activate RAS at the appropriate sublocalization for an adequate period while avoiding switching on opposing RAS signals. © 2016 Herrero 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).

  19. Plasma Cell Alloantigen 1 and IL-10 Secretion Define Two Distinct Peritoneal B1a B Cell Subsets With Opposite Functions, PC1high Cells Being Protective and PC1low Cells Harmful for the Growing Fetus

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    Anne Schumacher

    2018-05-01

    Full Text Available B cells possess various immuno regulatory functions. However, research about their participation in tolerance induction toward the fetus is just emerging. Accumulating evidence supports the idea that B cells can play seemingly conflicting roles during pregnancy, either protecting or harming the fetus. Previous findings indicated the presence of two different peritoneal B cell subsets, defined by the expression of the plasma cell alloantigen 1 (PC1 and with distinct immune modulatory functions. Here, we aimed to study the participation of these two B cell subsets, on pregnancy outcome in a murine model of disturbed fetal tolerance. The frequencies and cell numbers of peritoneal and splenic CD19+IL-10+ and CD19+CD5+IL-10+PC1+ cells were assessed in virgin as well as normal pregnant (NP and abortion-prone (AP females during the course of gestation. Peritoneal PC1low or PC1high B1a B cells were sorted, analyzed for their ability to secrete IL-10 and adoptively transferred into NP or AP females. On gestation day (gd 12, the abortion rate as well as the frequencies and cell numbers of regulatory T cells, TH1 and TH17 cells were determined in spleens and decidua. In addition, mRNA expression of IL-10, TGF-β, IFN-γ, and TNF-α was analyzed in decidual tissue. Peritoneal CD19+IL-10+ and CD19+CD5+IL-10+PC1+ frequencies fluctuated during the progression of normal pregnancies while no significant changes were observed in spleen. AP females showed significantly reduced frequencies of both B cell populations and exhibited an altered peritoneal PC1high/PC1low ratio at gd10. Adoptive transfers of PC1low B1a B cells into NP females increased the abortion rate in association with a reduced splenic regulatory T/TH17 ratio. By contrast, the transfer of PC1high B1a B cells into AP females significantly diminished the fetal rejection rate and significantly reduced the numbers of splenic TH17 cells. Our results suggest that the peritoneum harbors two distinct B1a B

  20. Molecular characterization of circulating colorectal tumor cells defines genetic signatures for individualized cancer care

    Science.gov (United States)

    Kong, Say Li; Liu, Xingliang; Suhaimi, Nur-Afidah Mohamed; Koh, Kenneth Jia Hao; Hu, Min; Lee, Daniel Yoke San; Cima, Igor; Phyo, Wai Min; Lee, Esther Xing Wei; Tai, Joyce A.; Foong, Yu Miin; Vo, Jess Honganh; Koh, Poh Koon; Zhang, Tong; Ying, Jackie Y.; Lim, Bing; Tan, Min-Han; Hillmer, Axel M.

    2017-01-01

    Studies on circulating tumor cells (CTCs) have largely focused on platform development and CTC enumeration rather than on the genomic characterization of CTCs. To address this, we performed targeted sequencing of CTCs of colorectal cancer patients and compared the mutations with the matched primary tumors. We collected preoperative blood and matched primary tumor samples from 48 colorectal cancer patients. CTCs were isolated using a label-free microfiltration device on a silicon microsieve. Upon whole genome amplification, we performed amplicon-based targeted sequencing on a panel of 39 druggable and frequently mutated genes on both CTCs and fresh-frozen tumor samples. We developed an analysis pipeline to minimize false-positive detection of somatic mutations in amplified DNA. In 60% of the CTC-enriched blood samples, we detected primary tumor matching mutations. We found a significant positive correlation between the allele frequencies of somatic mutations detected in CTCs and abnormal CEA serum level. Strikingly, we found driver mutations and amplifications in cancer and druggable genes such as APC, KRAS, TP53, ERBB3, FBXW7 and ERBB2. In addition, we found that CTCs carried mutation signatures that resembled the signatures of their primary tumors. Cumulatively, our study defined genetic signatures and somatic mutation frequency of colorectal CTCs. The identification of druggable mutations in CTCs of preoperative colorectal cancer patients could lead to more timely and focused therapeutic interventions. PMID:28978093

  1. Doppler-Defined Pulmonary Hypertension in Sickle Cell Anemia in Kurdistan, Iraq.

    Science.gov (United States)

    Al-Allawi, Nasir; Mohammad, Ameen M; Jamal, Shakir

    2016-01-01

    To determine the frequency, clinical and laboratory associations of pulmonary hypertension in Iraqi Kurds with sickle cell anemia, a total of ninety four such patients attending a major hemoglobinopathy center in Iraqi Kurdistan were enrolled. All patients were re-evaluated clinically and had their blood counts, HbF, serum ferritin, LDH, renal and liver function assessed. Transthoracic Doppler echocardiography with measurement of tricuspid valve regurgitant jet velocity (TRV) was performed. A TRV in excess of 2.8 m/s was considered for the purposes of this study as indicative of pulmonary hypertension (PH). The prevalence of TRV in excess of 2.8m/s was 10.6%. By univariate analysis: significantly higher reticulocyte count, more frequent blood transfusions and pain episodes were encountered in the PH group as compared to the non-PH group (p = 0.001, 0.045 and 0.02 respectively). Moreover, PH patients had significantly higher mean right atrial area, left atrial size, E wave/A wave ratio and ejection fraction by echocardiography (p = 0.027, 0.037, <0.001 and 0.008 respectively). Except for reticulocyte count none of the other parameters remained significant by multivariate analysis (p = 0.024). In conclusion the current study revealed that pulmonary hypertension is rather frequent among Iraqi Kurds with sickle cell anemia, and identified reticulocyte count as an independently associated parameter with PH in this population. Future prospective studies including right heart catheterization and appropriate medical intervention are warranted.

  2. A 10-year incidence of acute whiplash injuries after road traffic crashes in a defined population in northern Sweden.

    Science.gov (United States)

    Styrke, Johan; Stålnacke, Britt-Marie; Bylund, Per-Olof; Sojka, Peter; Björnstig, Ulf

    2012-10-01

    To examine the annual incidence of acute whiplash injuries after road traffic crashes in a geographic catchment area in Northern Sweden during the period 2000-2009. Descriptive epidemiology determined by prospectively collected data from a defined population. The study was conducted at a public hospital in Sweden. The population of the hospital's catchment area (136,600 inhabitants in 1999 and 144,500 in 2009). At the emergency department, all injured persons (approximately 11,000 per year) were asked to answer a questionnaire about the injury incident. Data from the medical records also were analyzed. From 2000-2009, 15,506 persons were injured in vehicle crashes. Persons who were subject to an acute neck injury within whiplash-associated disorder grades 1-3 were included. The overall and annual incidences were calculated as incidence. Age, gender, type of injury event, and direction of impact were described. The incidences were compared with national statistics on insurance claims from 2003, 2007, and 2008 to detect changes in the proportions of claims. The annual incidence of acute whiplash injuries. Secondary outcome measures were types of injury events, age and gender distribution, changes in the proportion of rear-end crashes during 2000-2009, and changes in the proportion of insurance claims during 2003-2008. During 2000-2009, 3297 cases of acute whiplash injury were encountered. The overall incidence was 235/100,000/year. The average yearly increase in incidence was 1.0%. Women comprised 51.9% and men 48.1% of the injured. Car occupants (86.4%) and bicycle riders (6.1%) were most frequently injured. The proportion of rear-end crashes decreased from 55% to 45% from 2000-2009. The proportion of insurance claims significantly decreased between 2003 and 2008 (P whiplash injuries after road traffic crashes have been relatively stable during the past decade in our area, except in 2007 and 2008, when a peak occurred. Copyright © 2012 American Academy of Physical

  3. Bridging the Timescales of Single-Cell and Population Dynamics

    Science.gov (United States)

    Jafarpour, Farshid; Wright, Charles S.; Gudjonson, Herman; Riebling, Jedidiah; Dawson, Emma; Lo, Klevin; Fiebig, Aretha; Crosson, Sean; Dinner, Aaron R.; Iyer-Biswas, Srividya

    2018-04-01

    How are granular details of stochastic growth and division of individual cells reflected in smooth deterministic growth of population numbers? We provide an integrated, multiscale perspective of microbial growth dynamics by formulating a data-validated theoretical framework that accounts for observables at both single-cell and population scales. We derive exact analytical complete time-dependent solutions to cell-age distributions and population growth rates as functionals of the underlying interdivision time distributions, for symmetric and asymmetric cell division. These results provide insights into the surprising implications of stochastic single-cell dynamics for population growth. Using our results for asymmetric division, we deduce the time to transition from the reproductively quiescent (swarmer) to the replication-competent (stalked) stage of the Caulobacter crescentus life cycle. Remarkably, population numbers can spontaneously oscillate with time. We elucidate the physics leading to these population oscillations. For C. crescentus cells, we show that a simple measurement of the population growth rate, for a given growth condition, is sufficient to characterize the condition-specific cellular unit of time and, thus, yields the mean (single-cell) growth and division timescales, fluctuations in cell division times, the cell-age distribution, and the quiescence timescale.

  4. DNA Methylation and Somatic Mutations Converge on the Cell Cycle and Define Similar Evolutionary Histories in Brain Tumors

    NARCIS (Netherlands)

    T. Mazor (Tali); A. Pankov (Aleksandr); B.E. Johnson (Brett E.); C. Hong (Chibo); E.G. Hamilton (Emily G.); R.J.A. Bell (Robert J.A.); I.V. Smirnov (Ivan V.); G.F. Reis (Gerald F.); J.J. Phillips (Joanna J.); M.J. Barnes (Michael); A. Idbaih (Ahmed); A. Alentorn (Agusti); J.J. Kloezeman (Jenneke); M.L.M. Lamfers (Martine); A.W. Bollen (Andrew W.); B.S. Taylor (Barry S.); A.M. Molinaro (Annette M.); A. Olshen (Adam); S.M. Chang (Susan); J.S. Song (Jun S.); J.F. Costello (Joseph F.)

    2015-01-01

    textabstractThe evolutionary history of tumor cell populations can be reconstructed from patterns of genetic alterations. In contrast to stable genetic events, epigenetic states are reversible and sensitive to the microenvironment, prompting the question whether epigenetic information can similarly

  5. Identification of a novel dendritic cell surface antigen defined by carbohydrate specific CD24 antibody cross-reactivity.

    Science.gov (United States)

    Williams, L A; McLellan, A D; Summers, K L; Sorg, R V; Fearnley, D B; Hart, D N

    1996-01-01

    Dendritic cells (DC) are characterized as leucocytes that lack mature lineage specific markers and stimulate naive T-lymphocyte proliferation in vitro and in vivo. The mouse heat stable antigen (HSA) participates in T lymphocyte co-stimulation and is expressed by DC isolated from thymus, skin and spleen. The human HSA homologue, CD24, is predominantly expressed by B lymphocytes and granulocytes, but its expression on DC has not been studied in detail. CD24 clearly participates in B-lymphocyte signalling but co-stimulatory activity for T lymphocytes has not yet been described. We have examined the expression of CD24 on human peripheral blood DC populations isolated directly or following in vitro culture. The CD24 antigen was absent from blood DC however, cross-reactive sialylated carbohydrate epitopes were detected on DC with some CD24 monoclonal antibodies (mAb). These CD24 mAb define a protein surface antigen, which is expressed by an immature or resting subpopulation of peripheral blood DC and is down-regulated following activation differentiation in vitro. PMID:8911149

  6. Progenitor cell populations in the periodontal ligament of mice

    International Nuclear Information System (INIS)

    McCulloch, C.A.

    1985-01-01

    Stem cells in a variety of renewal tissues exhibit a slow rate of cell proliferation. The periodontal ligament of mouse molars was examined for the presence of slowly cycling progenitor cells to provide evidence for the existence of stem cells in this tissue. A pulse injection of 3 H-thymidine was administered and mice were sacrificed between 1 hour and 14 days after injection. Analysis of radioautographs using percentage of labeled cells and grain counts demonstrated that a population of label-retaining cells within 10 micron of blood vessels traversed the cell cycle more slowly than proliferating cells located greater than 10 micron from blood vessels. These data suggest that there is a slowly dividing population of progenitor cells in paravascular sites in mouse molar periodontal ligament which may be stem cells

  7. Tumourigenic canine osteosarcoma cell lines associated with frizzled-6 up-regulation and enhanced side population cell frequency.

    Science.gov (United States)

    de Sá Rodrigues, L C; Holmes, K E; Thompson, V; Newton, M A; Stein, T J

    2017-03-01

    An increased serum alkaline phosphatase concentration is known to be associated with a negative prognosis in canine and human osteosarcoma. To expand upon previous studies regarding the biological relevance of increased serum alkaline phosphatase as a negative prognostic factor, xenogeneic heterotopic transplants were performed using six canine primary osteosarcoma cell lines generated from patients with differing serum alkaline phosphatase concentrations (three normal and three increased). Three of the six cell lines were capable of generating tumours and tumour formation was independent of the serum alkaline phosphatase status of the cell line. Microarray analysis identified 379 genes as being differentially expressed between the tumourigenic and non-tumourigenic cell lines. Frizzled-6 was upregulated to the greatest extent (7.78-fold) in tumourigenic cell lines compared with non-tumourigenic cell lines. Frizzled-6, a co-receptor for Wnt ligands has been associated with enhanced tumour-initiating cells and poor prognosis for other tumours. The increased expression of frizzled-6 was confirmed by quantitative reverse transcription polymerase chain reaction (QPCR) and Western blot analysis. Additionally, the tumourigenic cell lines also had an increase in the percentage of side population cells compared with non-tumourigenic cell lines (5.89% versus 1.58%, respectively). There were no differences in tumourigenicity, frizzled-6 or percentage of side population cells noted between osteosarcoma cell lines generated from patients of differing serum alkaline phosphatase concentration. However, to our knowledge this is the first study to identified frizzled-6 as a possible marker of osteosarcoma cell populations with enhanced tumourigenicity and side population cells. Future work will focus on defining the role of frizzled-6 in osteosarcoma tumourigenesis and tumour-initiating cells. © 2015 John Wiley & Sons Ltd.

  8. Precommitment low-level Neurog3 expression defines a long-lived mitotic endocrine-biased progenitor pool that drives production of endocrine-committed cells

    Science.gov (United States)

    Bechard, Matthew E.; Bankaitis, Eric D.; Hipkens, Susan B.; Ustione, Alessandro; Piston, David W.; Yang, Yu-Ping; Magnuson, Mark A.; Wright, Christopher V.E.

    2016-01-01

    The current model for endocrine cell specification in the pancreas invokes high-level production of the transcription factor Neurogenin 3 (Neurog3) in Sox9+ bipotent epithelial cells as the trigger for endocrine commitment, cell cycle exit, and rapid delamination toward proto-islet clusters. This model posits a transient Neurog3 expression state and short epithelial residence period. We show, however, that a Neurog3TA.LO cell population, defined as Neurog3 transcriptionally active and Sox9+ and often containing nonimmunodetectable Neurog3 protein, has a relatively high mitotic index and prolonged epithelial residency. We propose that this endocrine-biased mitotic progenitor state is functionally separated from a pro-ductal pool and endows them with long-term capacity to make endocrine fate-directed progeny. A novel BAC transgenic Neurog3 reporter detected two types of mitotic behavior in Sox9+ Neurog3TA.LO progenitors, associated with progenitor pool maintenance or derivation of endocrine-committed Neurog3HI cells, respectively. Moreover, limiting Neurog3 expression dramatically increased the proportional representation of Sox9+ Neurog3TA.LO progenitors, with a doubling of its mitotic index relative to normal Neurog3 expression, suggesting that low Neurog3 expression is a defining feature of this cycling endocrine-biased state. We propose that Sox9+ Neurog3TA.LO endocrine-biased progenitors feed production of Neurog3HI endocrine-committed cells during pancreas organogenesis. PMID:27585590

  9. Heterogeneity within populations of recombinant Chinese hamster ovary cells expressing human interferon-gamma.

    Science.gov (United States)

    Coppen, S R; Newsam, R; Bull, A T; Baines, A J

    1995-04-20

    The Chinese hamster ovary (CHO) cell line has great commercial importance in the production of recombinant human proteins, especially those for therapeutic use. Much attention has been paid to CHO cell population physiology in order to define factors affecting product fidelity and yield. Such studies have revealed that recombinant proteins, including human interferon-gamma (IFN-gamma), can be heterogeneous both in glycosylation and in proteolytic processing. The type of heterogeneity observed depends on the growth physiology of the cell population, although the relationship between them is complex. In this article we report results of a cytological study of the CHO320 line which expresses recombinant human IFN-gamma. When grown in suspension culture, this cell line exhibited three types of heterogeneity: (1) heterogeneity of the production of IFN-gamma within the cell population, (2) heterogeneity of the number of nuclei and mitotic spindles in dividing cells, and (3) heterogeneity of cellular environment. The last of these arises from cell aggregates which form in suspension culture: Some cells are exposed to the culture medium; others are fully enclosed within the mass with little or no direct access to the medium. Thus, live cells producing IFN-gamma are heterogeneous in their environment, with variable access to O(2) and nutrients. Within the aggregates, it appears that live cells proliferate on a dead cell mass. The layer of live cells can be several cells deep. Specific cell-cell attachments are observed between the living cells in these aggregates. Two proteins, known to be required for the formation of certain types of intercellular junctions, spectrin and vinculin, have been localized to the regions of cell-cell contact. The aggregation of the cells appears to be an active process requiring protein synthesis. (c) 1995 John Wiley & Sons, Inc.

  10. Controlling the diversity of cell populations in a stem cell culture

    NARCIS (Netherlands)

    Heo, Inha; Clevers, Hans

    2015-01-01

    Culturing intestinal stem cells into 3D organoids results in heterogeneous cell populations, reflecting the in vivo cell type diversity. In a recent paper published in Nature, Wang et al. established a culture condition for a highly homogeneous population of intestinal stem cells.

  11. Trends in colorectal cancer incidence: a period and birth-cohort analysis in a well-defined French population.

    Science.gov (United States)

    Chauvenet, Marion; Cottet, Vanessa; Lepage, Côme; Jooste, Valérie; Faivre, Jean; Bouvier, Anne-Marie

    2011-06-30

    France stands among high-risk areas for colorectal cancer. Different trends in CRC incidence are reported around the world. The aim of this study was to provide temporal trends in CRC incidence over a 30-year period in a French well-defined population. Between 1976 and 2005, 17,028 new cases were registered by the Burgundy digestive cancer registry. The mean variations in age-standardized incidence rates were estimated using a Poisson regression adjusted for age for each gender and location. The cumulative risk by birth cohort of developing a cancer over the age range 0-74 years was estimated using an age-cohort model. Incidence rates for right and left colon cancers increased more rapidly in males (respectively +11.7% and +10.3% on average by 5-year period) than in females (respectively +5.9% and +6.1%). It remained stable for sigmoid cancers in males (-0.1%) and decreased in females (-5.2%). It also decreased for rectal cancers both in males (-2.7%) and in females (-2.0%). The cumulative risk increased from 3.9% for males born around 1900 to 4.9% for those born around 1930 and then slightly decreased (4.5% among those born around 1950). It remained at the same level for females born around 1900 (2.7%) as for those born around 1930 (2.7%) and then slightly increased (2.9%) for those born around 1950. For right colon cancers, the cumulative risk increased strikingly in successive birth cohorts from 0.53% to 1.2% in males and 0.55% to 0.77% in females. The corresponding cumulative risks for the left colon were 0.24% and 0.42% in males and 0.14% and 0.29% in females. For sigmoid cancer, they decreased from 1.59% to 1.08% in males, and 0.88% to 0.80% in females. Temporal variations in incidence rates of colorectal cancers differed according to subsite, suggesting different aetiological factors and implications for diagnosis and screening strategies. Total colonoscopy must be the preferred strategy in high-risk groups or after a positive faecal occult blood test.

  12. Trends in colorectal cancer incidence: a period and birth-cohort analysis in a well-defined French population

    Directory of Open Access Journals (Sweden)

    Faivre Jean

    2011-06-01

    Full Text Available Abstract Background France stands among high-risk areas for colorectal cancer. Different trends in CRC incidence are reported around the world. The aim of this study was to provide temporal trends in CRC incidence over a 30-year period in a French well-defined population. Methods Between 1976 and 2005, 17,028 new cases were registered by the Burgundy digestive cancer registry. The mean variations in age-standardized incidence rates were estimated using a Poisson regression adjusted for age for each gender and location. The cumulative risk by birth cohort of developing a cancer over the age range 0-74 years was estimated using an age-cohort model. Results Incidence rates for right and left colon cancers increased more rapidly in males (respectively +11.7% and +10.3% on average by 5-year period than in females (respectively +5.9% and +6.1%. It remained stable for sigmoid cancers in males (-0.1% and decreased in females (-5.2%. It also decreased for rectal cancers both in males (-2.7% and in females (-2.0%. The cumulative risk increased from 3.9% for males born around 1900 to 4.9% for those born around 1930 and then slightly decreased (4.5% among those born around 1950. It remained at the same level for females born around 1900 (2.7% as for those born around 1930 (2.7% and then slightly increased (2.9% for those born around 1950. For right colon cancers, the cumulative risk increased strikingly in successive birth cohorts from 0.53% to 1.2% in males and 0.55% to 0.77% in females. The corresponding cumulative risks for the left colon were 0.24% and 0.42% in males and 0.14% and 0.29% in females. For sigmoid cancer, they decreased from 1.59% to 1.08% in males, and 0.88% to 0.80% in females. Conclusion Temporal variations in incidence rates of colorectal cancers differed according to subsite, suggesting different aetiological factors and implications for diagnosis and screening strategies. Total colonoscopy must be the preferred strategy in high

  13. On interfaces between cell populations with different mobilities

    KAUST Repository

    Lorenzi, Tommaso

    2016-11-18

    Partial differential equations describing the dynamics of cell population densities from a fluid mechanical perspective can model the growth of avascular tumours. In this framework, we consider a system of equations that describes the interaction between a population of dividing cells and a population of non-dividing cells. The two cell populations are characterised by different mobilities. We present the results of numerical simulations displaying two-dimensional spherical waves with sharp interfaces between dividing and non-dividing cells. Furthermore, we numerically observe how different ratios between the mobilities change the morphology of the interfaces, and lead to the emergence of finger-like patterns of invasion above a threshold. Motivated by these simulations, we study the existence of one-dimensional travelling wave solutions.

  14. Mediating human stem cell behaviour via defined fibrous architectures by melt electrospinning writing.

    Science.gov (United States)

    Eichholz, Kian F; Hoey, David A

    2018-05-29

    The architecture within which cells reside is key to mediating their specific functions within the body. In this study, we use melt electrospinning writing (MEW) to fabricate cell micro-environments with various fibrous architectures to study their effect on human stem cell behaviour. We designed, built and optimised a MEW apparatus and used it to fabricate four different platform designs of 10.4±2μm fibre diameter, with angles between fibres on adjacent layers of 90°, 45°, 10° and R (random). Mechanical characterisation was conducted via tensile testing, and human skeletal stem cells (hSSCs) were seeded to scaffolds to study the effect of architecture on cell morphology and mechanosensing (nuclear YAP). Cell morphology was significantly altered between groups, with cells on 90° scaffolds having a lower aspect ratio, greater spreading, greater cytoskeletal tension and nuclear YAP expression. Long term cell culture studies were then conducted to determine the differentiation potential of scaffolds in terms of alkaline phosphatase activity, collagen and mineral production. Across these studies, an increased cell spreading in 3-dimensions is seen with decreasing alignment of architecture correlated with enhanced osteogenesis. This study therefore highlights the critical role of fibrous architecture in regulating stem cell behaviour with implications for tissue engineering and disease progression. This is the first study which has investigated the effect of controlled fibrous architectures fabricated via melt electrospinning writing on cell behaviour and differentiation. After optimising the process and characterising scaffolds via SEM and tensile testing, cells were seeded to fibrous scaffolds with various micro-architectures and studied in terms of cell morphology. Nuclear YAP expression was further investigated as a marker of cell shape, cytoskeletal tension and differentiation potential. In agreement with these early markers, long term cell culture studies

  15. Direct induction of chondrogenic cells from human dermal fibroblast culture by defined factors.

    Directory of Open Access Journals (Sweden)

    Hidetatsu Outani

    Full Text Available The repair of large cartilage defects with hyaline cartilage continues to be a challenging clinical issue. We recently reported that the forced expression of two reprogramming factors (c-Myc and Klf4 and one chondrogenic factor (SOX9 can induce chondrogenic cells from mouse dermal fibroblast culture without going through a pluripotent state. We here generated induced chondrogenic (iChon cells from human dermal fibroblast (HDF culture with the same factors. We developed a chondrocyte-specific COL11A2 promoter/enhancer lentiviral reporter vector to select iChon cells. The human iChon cells expressed marker genes for chondrocytes but not fibroblasts, and were derived from non-chondrogenic COL11A2-negative cells. The human iChon cells formed cartilage but not tumors in nude mice. This approach could lead to the preparation of cartilage directly from skin in human, without going through pluripotent stem cells.

  16. CD133+CD24lo defines a 5-Fluorouracil-resistant colon cancer stem cell-like phenotype

    Science.gov (United States)

    Paschall, Amy V.; Yang, Dafeng; Lu, Chunwan; Redd, Priscilla S.; Choi, Jeong-Hyeon; Heaton, Christopher M.; Lee, Jeffrey R.; Nayak-Kapoor, Asha; Liu, Kebin

    2016-01-01

    The chemotherapeutic agent 5-Fluorouracil (5-FU) is the most commonly used drug for patients with advanced colon cancer. However, development of resistance to 5-FU is inevitable in almost all patients. The mechanism by which colon cancer develops 5-FU resistance is still unclear. One recently proposed theory is that cancer stem-like cells underlie colon cancer 5-FU resistance, but the phenotypes of 5-FU-resistant colon cancer stem cells are still controversial. We report here that 5-FU treatment selectively enriches a subset of CD133+ colon cancer cells in vitro. 5-FU chemotherapy also increases CD133+ tumor cells in human colon cancer patients. However, sorted CD133+ colon cancer cells exhibit no increased resistance to 5-FU, and CD133 levels exhibit no correlation with colon cancer patient survival or cancer recurrence. Genome-wide analysis of gene expression between sorted CD133+ colon cancer cells and 5-FU-selected colon cancer cells identifies 207 differentially expressed genes. CD24 is one of the genes whose expression level is lower in the CD133+ and 5-FU-resistant colon cancer cells as compared to CD133+ and 5-FU-sensitive colon cancer cells. Consequently, CD133+CD24lo cells exhibit decreased sensitivity to 5-FU. Therefore, we determine that CD133+CD24lo phenotype defines 5-FU-resistant human colon cancer stem cell-like cells. PMID:27659530

  17. Association between pregnancy complications and small-for-gestational-age birth weight defined by customized fetal growth standard versus a population-based standard.

    Science.gov (United States)

    Odibo, Anthony O; Francis, Andre; Cahill, Alison G; Macones, George A; Crane, James P; Gardosi, Jason

    2011-03-01

    To derive coefficients for developing a customized growth chart for a Mid-Western US population, and to estimate the association between pregnancy outcomes and smallness for gestational age (SGA) defined by the customized growth chart compared with a population-based growth chart for the USA. A retrospective cohort study of an ultrasound database using 54,433 pregnancies meeting inclusion criteria was conducted. Coefficients for customized centiles were derived using 42,277 pregnancies and compared with those obtained from other populations. Two adverse outcome indicators were defined (greater than 7 day stay in the neonatal unit and stillbirth [SB]), and the risk for each outcome was calculated for the groups of pregnancies defined as SGA by the population standard and SGA by the customized standard using 12,456 pregnancies for the validation sample. The growth potential expressed as weight at 40 weeks in this population was 3524 g (standard error: 402 g). In the validation population, 4055 cases of SGA were identified using both population and customized standards. The cases additionally identified as SGA by the customized method had a significantly increased risk of each of the adverse outcome categories. The sensitivity and specificity of those identified as SGA by customized method only for detecting pregnancies at risk for SB was 32.7% (95% confidence interval [CI] 27.0-38.8%) and 95.1% (95% CI: 94.7-95.0%) versus 0.8% (95% CI 0.1-2.7%) and 98.0% (95% CI 97.8-98.2%)for those identified by only the population-based method, respectively. SGA defined by customized growth potential is able to identify substantially more pregnancies at a risk for adverse outcome than the currently used national standard for fetal growth.

  18. Derivation of human differential photoreceptor-like cells from the iris by defined combinations of CRX, RX and NEUROD.

    Directory of Open Access Journals (Sweden)

    Yuko Seko

    Full Text Available Examples of direct differentiation by defined transcription factors have been provided for beta-cells, cardiomyocytes and neurons. In the human visual system, there are four kinds of photoreceptors in the retina. Neural retina and iris-pigmented epithelium (IPE share a common developmental origin, leading us to test whether human iris cells could differentiate to retinal neurons. We here define the transcription factor combinations that can determine human photoreceptor cell fate. Expression of rhodopsin, blue opsin and green/red opsin in induced photoreceptor cells were dependent on combinations of transcription factors: A combination of CRX and NEUROD induced rhodopsin and blue opsin, but did not induce green opsin; a combination of CRX and RX induced blue opsin and green/red opsin, but did not induce rhodopsin. Phototransduction-related genes as well as opsin genes were up-regulated in those cells. Functional analysis; i.e. patch clamp recordings, clearly revealed that generated photoreceptor cells, induced by CRX, RX and NEUROD, responded to light. The response was an inward current instead of the typical outward current. These data suggest that photosensitive photoreceptor cells can be generated by combinations of transcription factors. The combination of CRX and RX generate immature photoreceptors: and additional NEUROD promotes maturation. These findings contribute substantially to a major advance toward eventual cell-based therapy for retinal degenerative diseases.

  19. On interfaces between cell populations with different mobilities

    KAUST Repository

    Lorenzi, Tommaso; Lorz, Alexander; Perthame, Benoit

    2016-01-01

    Partial differential equations describing the dynamics of cell population densities from a fluid mechanical perspective can model the growth of avascular tumours. In this framework, we consider a system of equations that describes the interaction

  20. Pregnancy persistently affects memory T cell populations

    NARCIS (Netherlands)

    Kieffer, Tom E. C.; Faas, Marijke M.; Scherjon, Sicco A.; Prins, Jelmer R.

    Pregnancy is an immune challenge to the maternal immune system. The effects of pregnancy on maternal immunity and particularly on memory T cells during and after pregnancy are not fully known. This observational study aims to show the short term and the long term effects of pregnancy on the

  1. Emergence of cytotoxic resistance in cancer cell populations: Single-cell mechanisms and population-level consequences

    International Nuclear Information System (INIS)

    Lorenzi, Tommaso; Chisholm, Rebecca H.; Lorz, Alexander; Neves de Almeida, Luís; Clairambault, Jean; Larsen, Annette K.; Escargueil, Alexandre

    2016-01-01

    We formulate an individual-based model and a population model of phenotypic evolution, under cytotoxic drugs, in a cancer cell population structured by the expression levels of survival-potential and proliferation-potential. We apply these models to a recently studied experimental system. Our results suggest that mechanisms based on fundamental laws of biology can reversibly push an actively-proliferating, and drug-sensitive, cell population to transition into a weakly-proliferative and drug-tolerant state, which will eventually facilitate the emergence of more potent, proliferating and drug-tolerant cells.

  2. Emergence of cytotoxic resistance in cancer cell populations: Single-cell mechanisms and population-level consequences

    Energy Technology Data Exchange (ETDEWEB)

    Lorenzi, Tommaso [Centre de Mathématiques et de Leurs Applications, ENS Cachan, CNRS, Cachan 94230 Cedex, France & INRIA-Paris-Rocquencourt, MAMBA Team, Domaine de Voluceau, BP105, 78153 Le Chesnay Cedex (France); Chisholm, Rebecca H. [School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney NSW 2052 (Australia); Lorz, Alexander; Neves de Almeida, Luís; Clairambault, Jean [Sorbonne Universités, UPMC Univ Paris 06, UMR 7598, Laboratoire Jacques-Louis Lions, F-75005, Paris (France); CNRS, UMR 7598, Laboratoire Jacques-Louis Lions, F-75005, Paris (France); INRIA-Paris-Rocquencourt, MAMBA Team, Domaine de Voluceau, BP105, 78153 Le Chesnay Cedex (France); Larsen, Annette K.; Escargueil, Alexandre [Sorbonne Universités, UPMC Univ Paris 06, F-75005, Paris (France); INSERM, UMR-S 938, Laboratory of “Cancer Biology and Therapeutics”, F-75012, Paris (France)

    2016-06-08

    We formulate an individual-based model and a population model of phenotypic evolution, under cytotoxic drugs, in a cancer cell population structured by the expression levels of survival-potential and proliferation-potential. We apply these models to a recently studied experimental system. Our results suggest that mechanisms based on fundamental laws of biology can reversibly push an actively-proliferating, and drug-sensitive, cell population to transition into a weakly-proliferative and drug-tolerant state, which will eventually facilitate the emergence of more potent, proliferating and drug-tolerant cells.

  3. Nonequilibrium population dynamics of phenotype conversion of cancer cells.

    Directory of Open Access Journals (Sweden)

    Joseph Xu Zhou

    Full Text Available Tumorigenesis is a dynamic biological process that involves distinct cancer cell subpopulations proliferating at different rates and interconverting between them. In this paper we proposed a mathematical framework of population dynamics that considers both distinctive growth rates and intercellular transitions between cancer cell populations. Our mathematical framework showed that both growth and transition influence the ratio of cancer cell subpopulations but the latter is more significant. We derived the condition that different cancer cell types can maintain distinctive subpopulations and we also explain why there always exists a stable fixed ratio after cell sorting based on putative surface markers. The cell fraction ratio can be shifted by changing either the growth rates of the subpopulations (Darwinism selection or by environment-instructed transitions (Lamarckism induction. This insight can help us to understand the dynamics of the heterogeneity of cancer cells and lead us to new strategies to overcome cancer drug resistance.

  4. CRISPR/Cas9-Mediated Mutagenesis of Human Pluripotent Stem Cells in Defined Xeno-Free E8 Medium.

    Science.gov (United States)

    Soh, Chew-Li; Huangfu, Danwei

    2017-01-01

    The recent advent of engineered nucleases including the CRISPR/Cas9 system has greatly facilitated genome manipulation in human pluripotent stem cells (hPSCs). In addition to facilitating hPSC-based disease studies, the application of genome engineering in hPSCs has also opened up new avenues for cell replacement therapy. To improve consistency and reproducibility of hPSC-based studies, and to meet the safety and regulatory requirements for clinical translation, it is necessary to use a defined, xeno-free cell culture system. This chapter describes protocols for CRISPR/Cas9 genome editing in an inducible Cas9 hPSC-based system, using cells cultured in chemically defined, xeno-free E8 Medium on a recombinant human vitronectin substrate. We detail procedures for the design and transfection of CRISPR guide RNAs, colony selection, and the expansion and validation of clonal mutant lines, all within this fully defined culture condition. These methods may be applied to a wide range of genome-engineering applications in hPSCs, including those that utilize different types of site-specific nucleases such as zinc finger nucleases (ZFNs) and TALENs, and form a closer step towards clinical utility of these cells.

  5. Concise Review: Stem Cell Population Biology: Insights from Hematopoiesis.

    Science.gov (United States)

    MacLean, Adam L; Lo Celso, Cristina; Stumpf, Michael P H

    2017-01-01

    Stem cells are fundamental to human life and offer great therapeutic potential, yet their biology remains incompletely-or in cases even poorly-understood. The field of stem cell biology has grown substantially in recent years due to a combination of experimental and theoretical contributions: the experimental branch of this work provides data in an ever-increasing number of dimensions, while the theoretical branch seeks to determine suitable models of the fundamental stem cell processes that these data describe. The application of population dynamics to biology is amongst the oldest applications of mathematics to biology, and the population dynamics perspective continues to offer much today. Here we describe the impact that such a perspective has made in the field of stem cell biology. Using hematopoietic stem cells as our model system, we discuss the approaches that have been used to study their key properties, such as capacity for self-renewal, differentiation, and cell fate lineage choice. We will also discuss the relevance of population dynamics in models of stem cells and cancer, where competition naturally emerges as an influential factor on the temporal evolution of cell populations. Stem Cells 2017;35:80-88. © 2016 AlphaMed Press.

  6. Selection of chemically defined media for CHO cell fed-batch culture processes

    NARCIS (Netherlands)

    Pan, X.; Streefland, M.; Dalm, C.; Wijffels, R.H.; Martens, D.E.

    2017-01-01

    Two CHO cell clones derived from the same parental CHOBC cell line and producing the same monoclonal antibody (BC-G, a low producing clone; BC-P, a high producing clone) were tested in four basal media in all possible combinations with three feeds (=12 conditions) in fed-batch cultures.
    Higher

  7. Mycobacterium leprae-specific protein antigens defined by cloned human helper T cells

    NARCIS (Netherlands)

    Ottenhoff, T. H.; Klatser, P. R.; Ivanyi, J.; Elferink, D. G.; de Wit, M. Y.; de Vries, R. R.

    1986-01-01

    Leprosy displays a remarkable spectrum of symptoms correlating with the T-cell-mediated immune reactivity of the host against the causative organism, Mycobacterium leprae. At one pole of this spectrum are lepromatous leprosy patients showing a M. leprae-specific T-cell unresponsiveness; at the other

  8. Cell-Type Specific DNA Methylation Patterns Define Human Breast Cellular Identity

    Czech Academy of Sciences Publication Activity Database

    Novák, Petr; Stampfer, M.R.; Munoz-Rodriguez, J.L.; Garbe, J.C.; Ehrich, M.; Futscher, B. W.; Jensen, T.J.

    2012-01-01

    Roč. 7, č. 12 (2012), e52299 E-ISSN 1932-6203 Institutional research plan: CEZ:AV0Z50510513 Institutional support: RVO:60077344 Keywords : MAMMARY EPITHELIAL-CELLS * PLURIPOTENT STEM-CELLS * CPG ISLAND SHORES Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.730, year: 2012

  9. A descriptive study of plasma cell dyscrasias in Egyptian population

    International Nuclear Information System (INIS)

    Kassem, N.M.; Kassem, H.A.; EL Zawam, H.; EL Nahas, T.; Abd El Azeeim, H.; Abd El Azeeim; El Husseiny, N.M.

    2014-01-01

    Background: Plasma cell dyscrasias (PCDs) refer to a spectrum of disorders characterized by the monoclonal proliferation of lymphoplasmacytic cells in the bone marrow and, sometimes, tissue deposition of monoclonal immunoglobulins or their components. These disorders include multiple myeloma (MM) and Waldenstrom’s macroglobulinemia, as well as rare conditions such as light-chain deposition disease (LCDD) and heavy-chain diseases (HCDs). The worldwide annual incidence of MM is estimated at 86,000, which is approximately 0.8% of all new cancer cases. Purpose: Our retrospective study aims to highlight the immunologic and epidemiological features of PCDs mainly MM in Egyptian patients and compare our results with those of other populations. Methods: Two hundred seventeen Egyptian patients with PCD were enrolled in the study. Serum, urine protein electrophoresis and immunofixation were used to demonstrate M protein. Results: One hundred thirty-eight patients (63.6%) had IgG monoclonal band, 38 patients (17.5%) had IgA, 12 patients (5.5%) had Waldenstrom’s macroglobulinemia (IgM monoclonal band) and 29 patients (13.4%) were light chain myeloma. One hundred fifty-one (70%) were Kappa chain positive and 66 patients (30%) were lumbda positive. Conventional cytogenetics was available for 40 patients; of them12 patients (30%) showed 13q-. Mean OS was 37.5 months (1-84 months). Survival analysis was statistically insignificant according to age, sex and ISS or type of treatment (P value >0.05). Conclusion: Long term follow up is required to further define the role of different therapeutic lines of treatment including ASCT in the various stages of PCD based on OS data.

  10. A descriptive study of plasma cell dyscrasias in Egyptian population.

    Science.gov (United States)

    Kassem, Neemat M; El Zawam, Hamdy; Kassem, Heba A; El Nahas, Tamer; El Husseiny, Noha M; El Azeeim, Hamdy Abd

    2014-06-01

    Plasma cell dyscrasias (PCDs) refer to a spectrum of disorders characterized by the monoclonal proliferation of lymphoplasmacytic cells in the bone marrow and, sometimes, tissue deposition of monoclonal immunoglobulins or their components. These disorders include multiple myeloma (MM) and Waldenström's macroglobulinemia, as well as rare conditions such as light-chain deposition disease (LCDD) and heavy-chain diseases (HCDs). The worldwide annual incidence of MM is estimated at 86,000, which is approximately 0.8% of all new cancer cases. Our retrospective study aims to highlight the immunologic and epidemiological features of PCDs mainly MM in Egyptian patients and compare our results with those of other populations. Two hundred seventeen Egyptian patients with PCD were enrolled in the study. Serum, urine protein electrophoresis and immunofixation were used to demonstrate M protein. One hundred thirty-eight patients (63.6%) had IgG monoclonal band, 38 patients (17.5%) had IgA, 12 patients (5.5%) had Waldenström's macroglobulinemia (IgM monoclonal band) and 29 patients (13.4%) were light chain myeloma. One hundred fifty-one (70%) were Kappa chain positive and 66 patients (30%) were lumbda positive. Conventional cytogenetics was available for 40 patients; of them12 patients (30%) showed 13q-. Mean OS was 37.5months (1-84months). Survival analysis was statistically insignificant according to age, sex and ISS or type of treatment (P value>0.05). Long term follow up is required to further define the role of different therapeutic lines of treatment including ASCT in the various stages of PCD based on OS data. Copyright © 2013. Production and hosting by Elsevier B.V.

  11. Wilms Tumor 1b defines a wound-specific sheath cell subpopulation associated with notochord repair

    Science.gov (United States)

    Lopez-Baez, Juan Carlos; Zeng, Zhiqiang; Brunsdon, Hannah; Salzano, Angela; Brombin, Alessandro; Wyatt, Cameron; Rybski, Witold; Huitema, Leonie F A; Dale, Rodney M; Kawakami, Koichi; Englert, Christoph; Chandra, Tamir; Schulte-Merker, Stefan

    2018-01-01

    Regenerative therapy for degenerative spine disorders requires the identification of cells that can slow down and possibly reverse degenerative processes. Here, we identify an unanticipated wound-specific notochord sheath cell subpopulation that expresses Wilms Tumor (WT) 1b following injury in zebrafish. We show that localized damage leads to Wt1b expression in sheath cells, and that wt1b+cells migrate into the wound to form a stopper-like structure, likely to maintain structural integrity. Wt1b+sheath cells are distinct in expressing cartilage and vacuolar genes, and in repressing a Wt1b-p53 transcriptional programme. At the wound, wt1b+and entpd5+ cells constitute separate, tightly-associated subpopulations. Surprisingly, wt1b expression at the site of injury is maintained even into adult stages in developing vertebrae, which form in an untypical manner via a cartilage intermediate. Given that notochord cells are retained in adult intervertebral discs, the identification of novel subpopulations may have important implications for regenerative spine disorder treatments. PMID:29405914

  12. Niche-dependent development of functional neuronal networks from embryonic stem cell-derived neural populations

    Directory of Open Access Journals (Sweden)

    Siebler Mario

    2009-08-01

    Full Text Available Abstract Background The present work was performed to investigate the ability of two different embryonic stem (ES cell-derived neural precursor populations to generate functional neuronal networks in vitro. The first ES cell-derived neural precursor population was cultivated as free-floating neural aggregates which are known to form a developmental niche comprising different types of neural cells, including neural precursor cells (NPCs, progenitor cells and even further matured cells. This niche provides by itself a variety of different growth factors and extracellular matrix proteins that influence the proliferation and differentiation of neural precursor and progenitor cells. The second population was cultivated adherently in monolayer cultures to control most stringently the extracellular environment. This population comprises highly homogeneous NPCs which are supposed to represent an attractive way to provide well-defined neuronal progeny. However, the ability of these different ES cell-derived immature neural cell populations to generate functional neuronal networks has not been assessed so far. Results While both precursor populations were shown to differentiate into sufficient quantities of mature NeuN+ neurons that also express GABA or vesicular-glutamate-transporter-2 (vGlut2, only aggregate-derived neuronal populations exhibited a synchronously oscillating network activity 2–4 weeks after initiating the differentiation as detected by the microelectrode array technology. Neurons derived from homogeneous NPCs within monolayer cultures did merely show uncorrelated spiking activity even when differentiated for up to 12 weeks. We demonstrated that these neurons exhibited sparsely ramified neurites and an embryonic vGlut2 distribution suggesting an inhibited terminal neuronal maturation. In comparison, neurons derived from heterogeneous populations within neural aggregates appeared as fully mature with a dense neurite network and punctuated

  13. Defining differentially methylated regions specific for the acquisition of pluripotency and maintenance in human pluripotent stem cells via microarray.

    Directory of Open Access Journals (Sweden)

    WenYin He

    Full Text Available Epigenetic regulation is critical for the maintenance of human pluripotent stem cells. It has been shown that pluripotent stem cells, such as embryonic stem cells and induced pluripotent stem cells, appear to have a hypermethylated status compared with differentiated cells. However, the epigenetic differences in genes that maintain stemness and regulate reprogramming between embryonic stem cells and induced pluripotent stem cells remain unclear. Additionally, differential methylation patterns of induced pluripotent stem cells generated using diverse methods require further study.Here, we determined the DNA methylation profiles of 10 human cell lines, including 2 ESC lines, 4 virally derived iPSC lines, 2 episomally derived iPSC lines, and the 2 parental cell lines from which the iPSCs were derived using Illumina's Infinium HumanMethylation450 BeadChip. The iPSCs exhibited a hypermethylation status similar to that of ESCs but with distinct differences from the parental cells. Genes with a common methylation pattern between iPSCs and ESCs were classified as critical factors for stemness, whereas differences between iPSCs and ESCs suggested that iPSCs partly retained the parental characteristics and gained de novo methylation aberrances during cellular reprogramming. No significant differences were identified between virally and episomally derived iPSCs. This study determined in detail the de novo differential methylation signatures of particular stem cell lines.This study describes the DNA methylation profiles of human iPSCs generated using both viral and episomal methods, the corresponding somatic cells, and hESCs. Series of ss-DMRs and ES-iPS-DMRs were defined with high resolution. Knowledge of this type of epigenetic information could be used as a signature for stemness and self-renewal and provides a potential method for selecting optimal pluripotent stem cells for human regenerative medicine.

  14. Cells, bilirubin and light: formation of bilirubin photoproducts and cellular damage at defined wavelengths

    International Nuclear Information System (INIS)

    Christensen, T.; Kinn, G.; Granli, T.; Amundsen, I.

    1994-01-01

    Cultured cells from one human and one murine cell line were treated with bilirubin and irradiated with visible light of different wavelengths, either from phototherapy lamps or from a Xenon/Mercury lamp equipped with a monochromator. Bilirubin bound to human serum albumin was also irradiated with light. After irradiation, the bilirubin and its photoisomers were extracted with High Pressure Liquid Chromatography. The formation of single strand breaks in the DNA of treated cells was studied using a fluorescence marker. Cytotoxicity in the mouse skin cell line was measured by loss of the ability to form visible colonies in vitro. Green light exposure favours the production of lumirubin, while blue light causes more DNA damage and cytotoxicity. Green light may be more efficient and safer than shorter wavelength exposure when treating jaundiced newborns with phototherapy. 27 refs., 6 figs

  15. Specific profiles of ion channels and ionotropic receptors define adipose- and bone marrow derived stromal cells.

    Czech Academy of Sciences Publication Activity Database

    Forostyak, Oksana; Butenko, Olena; Anděrová, Miroslava; Forostyak, Serhiy; Syková, Eva; Verkhratsky, A.; Dayanithi, Govindan

    2016-01-01

    Roč. 16, č. 3 (2016), s. 622-634 ISSN 1873-5061 R&D Projects: GA ČR(CZ) GA14-34077S; GA ČR(CZ) GAP304/11/2373; GA ČR(CZ) GBP304/12/G069 Institutional support: RVO:68378041 Keywords : adipose derived stromal cells * bone marrow stromal cell * Ca(2+) signaling * Ion channels Subject RIV: FH - Neurology Impact factor: 3.494, year: 2016

  16. Emergence of cytotoxic resistance in cancer cell populations*

    Directory of Open Access Journals (Sweden)

    Lorenzi Tommaso

    2015-01-01

    Full Text Available We formulate an individual-based model and an integro-differential model of phenotypic evolution, under cytotoxic drugs, in a cancer cell population structured by the expression levels of survival-potential and proliferation-potential. We apply these models to a recently studied experimental system. Our results suggest that mechanisms based on fundamental laws of biology can reversibly push an actively-proliferating, and drug-sensitive, cell population to transition into a weakly-proliferative and drug-tolerant state, which will eventually facilitate the emergence of more potent, proliferating and drug-tolerant cells.

  17. Dielectrophoretic capture of low abundance cell population using thick electrodes

    OpenAIRE

    Marchalot, Julien; Chateaux, Jean-François; Faivre, Magalie; Mertani, Hichem C.; Ferrigno, Rosaria; Deman, Anne-Laure

    2015-01-01

    Enrichment of rare cell populations such as Circulating Tumor Cells (CTCs) is a critical step before performing analysis. This paper presents a polymeric microfluidic device with integrated thick Carbon-PolyDimethylSiloxane composite (C-PDMS) electrodes designed to carry out dielectrophoretic (DEP) trapping of low abundance biological cells. Such conductive composite material presents advantages over metallic structures. Indeed, as it combines properties of both the matrix and doping particle...

  18. The World Health Organisation Disability Assessment Scale (WHODAS II: Links between self-rated health and objectively defined and clinical parameters in the population of spinal cord injury

    Directory of Open Access Journals (Sweden)

    Steinerte V.

    2016-01-01

    Full Text Available There are many clinical and objectively defined parameters that are used to evaluate a person's disability. Since the World Health Organisation has presented the WHODAS II as a means of objectively measuring subjectively defined functions, greater attention has been focused on self-rated health. Only a few studies, however, have been conducted about differences between self-rated health and objectively defined parameters. The survey for this study was conducted on the basis of WHODAS II and the population in Latvia with spinal cord injury. Respondents were between 18 and 65, and 98 questionnaires were analysed. The results show that people with spinal cord injury on average rate their functioning as limited (33–40 points of 100. Most respondents have been declared to be disabled, which is defined as very serious or severe functional disorders. More than 40% have paid jobs, while one-third do not work for reasons of health. The research shows that there is a close coherence (p< 0.05 between individual, objectively and clinically defined indicators on the one hand and the aspects of the questionnaire in which physical functioning was an important factor on the other hand. In order to understand the real functional abilities of patients and the individual factors that influence those abilities, it is necessary to define functional self-rated health in addition to objectively defined indicators.

  19. Design of a Vitronectin-Based Recombinant Protein as a Defined Substrate for Differentiation of Human Pluripotent Stem Cells into Hepatocyte-Like Cells.

    Directory of Open Access Journals (Sweden)

    Masato Nagaoka

    Full Text Available Maintenance and differentiation of human pluripotent stem cells (hPSCs usually requires culture on a substrate for cell adhesion. A commonly used substratum is Matrigel purified from Engelbreth-Holm-Swarm sarcoma cells, and consists of a complex mixture of extracellular matrix proteins, proteoglycans, and growth factors. Several studies have successfully induced differentiation of hepatocyte-like cells from hPSCs. However, most of these studies have used Matrigel as a cell adhesion substrate, which is not a defined culture condition. In an attempt to generate a substratum that supports undifferentiated properties and differentiation into hepatic lineage cells, we designed novel substrates consisting of vitronectin fragments fused to the IgG Fc domain. hPSCs adhered to these substrates via interactions between integrins and the RGD (Arg-Gly-Asp motif, and the cells maintained their undifferentiated phenotypes. Using a previously established differentiation protocol, hPSCs were efficiently differentiated into mesendodermal and hepatic lineage cells on a vitronectin fragment-containing substrate. We found that full-length vitronectin did not support stable cell adhesion during the specification stage. Furthermore, the vitronectin fragment with the minimal RGD-containing domain was sufficient for differentiation of human induced pluripotent stem cells into hepatic lineage cells under completely defined conditions that facilitate the clinical application of cells differentiated from hPSCs.

  20. The prevalence of ALK rearrangement in pulmonary adenocarcinomas in an unselected Caucasian population from a defined catchment area

    DEFF Research Database (Denmark)

    Skov, Birgit G; Clementsen, Paul; Larsen, Klaus R

    2017-01-01

    . METHODS AND RESULTS: All patients diagnosed in the population of the greater Copenhagen area were included, irrespective of gender, age, smoking habits, stage or type of available diagnostic material. Tumours were stained with immunohistochemistry (clone 5A4). Immunohistochemistry-positive tumours were......AIMS: To assess the prevalence of EML4-ALK rearrangement gene measured by immunohistochemistry in an unselected population-based consecutive cohort of patients with adenocarcinoma of the lung (ACL), and the correlation with smoking history, thyroid transcription factor 1 (TTF1), gender and age...

  1. Extracellular signals that define distinct and coexisting cell fates in Bacillus subtilis.

    Science.gov (United States)

    López, Daniel; Kolter, Roberto

    2010-03-01

    The soil-dwelling bacterium Bacillus subtilis differentiates into distinct subpopulations of specialized cells that coexist within highly structured communities. The coordination and interplay between these cell types requires extensive extracellular communication driven mostly by sensing self-generated secreted signals. These extracellular signals activate a set of sensor kinases, which respond by phosphorylating three major regulatory proteins, Spo0A, DegU and ComA. Each phosphorylated regulator triggers a specific differentiation program while at the same time repressing other differentiation programs. This allows a cell to differentiate in response to a specific cue, even in the presence of other, possibly conflicting, signals. The sensor kinases involved respond to an eclectic group of extracellular signals, such as quorum-sensing molecules, natural products, temperature, pH or scarcity of nutrients. This article reviews the cascades of cell differentiation pathways that are triggered by sensing extracellular signals. We also present a tentative developmental model in which the diverse cell types sequentially differentiate to achieve the proper development of the bacterial community.

  2. Defined α-synuclein prion-like molecular assemblies spreading in cell culture.

    Science.gov (United States)

    Aulić, Suzana; Le, Tran Thanh Nhat; Moda, Fabio; Abounit, Saïda; Corvaglia, Stefania; Casalis, Loredana; Gustincich, Stefano; Zurzolo, Chiara; Tagliavini, Fabrizio; Legname, Giuseppe

    2014-06-04

    α-Synuclein (α-syn) plays a central role in the pathogenesis of synucleinopathies, a group of neurodegenerative disorders that includes Parkinson disease, dementia with Lewy bodies and multiple system atrophy. Several findings from cell culture and mouse experiments suggest intercellular α-syn transfer. Through a methodology used to obtain synthetic mammalian prions, we tested whether recombinant human α-syn amyloids can promote prion-like accumulation in neuronal cell lines in vitro. A single exposure to amyloid fibrils of human α-syn was sufficient to induce aggregation of endogenous α-syn in human neuroblastoma SH-SY5Y cells. Remarkably, endogenous wild-type α-syn was sufficient for the formation of these aggregates, and overexpression of the protein was not required. Our results provide compelling evidence that endogenous α-syn can accumulate in cell culture after a single exposure to exogenous α-syn short amyloid fibrils. Importantly, using α-syn short amyloid fibrils as seed, endogenous α-syn aggregates and accumulates over several passages in cell culture, providing an excellent tool for potential therapeutic screening of pathogenic α-syn aggregates.

  3. Use of Stakeholder Focus Groups to Define the Mission and Scope of a new Department of Population Health.

    Science.gov (United States)

    Tierney, William M

    2018-04-09

    The focus and funding of US healthcare is evolving from volume to value-based, and healthcare leaders, managers, payers, and researchers are increasingly focusing on managing populations of patients. Simultaneously, there is increasing interest in getting "upstream" from disease management to promote health and prevent disease. Hence, the term "population health" has both clinical and community-based connotations relevant to the tripartite mission of US medical schools. To seek broad input for the strategic development of the Department of Population Health in a new medical school at a tier 1 research university. Focus groups with facilitated consensus development. Eighty-one persons representing the Dell Medical School and other schools at the University of Texas at Austin, city/county government, community nonprofit organizations, and faculty from other local university schools along with selected national academic leaders. Focus groups with subsequent consensus development of emphases identified premeeting by participants by e-mail exchanges. The resulting departmental strategic plan included scope of work, desired characteristics of leaders, and early impact activities in seven areas of interest: community engagement and health equity, primary care and value-based health, occupational and environment medicine, medical education, health services and community-based research, health informatics and data analysis, and global health. Medical schools should have a primary focus in population, most effectively at the departmental level. Engaging relevant academic and community stakeholders is an effective model for developing this emerging discipline in US medical schools.

  4. Distinct types of glial cells populate the Drosophila antenna

    Directory of Open Access Journals (Sweden)

    Jhaveri Dhanisha

    2005-11-01

    Full Text Available Abstract Background The development of nervous systems involves reciprocal interactions between neurons and glia. In the Drosophila olfactory system, peripheral glial cells arise from sensory lineages specified by the basic helix-loop-helix transcription factor, Atonal. These glia wrap around the developing olfactory axons early during development and pattern the three distinct fascicles as they exit the antenna. In the moth Manduca sexta, an additional set of central glia migrate to the base of the antennal nerve where axons sort to their glomerular targets. In this work, we have investigated whether similar types of cells exist in the Drosophila antenna. Results We have used different P(Gal4 lines to drive Green Fluorescent Protein (GFP in distinct populations of cells within the Drosophila antenna. Mz317::GFP, a marker for cell body and perineural glia, labels the majority of peripheral glia. An additional ~30 glial cells detected by GH146::GFP do not derive from any of the sensory lineages and appear to migrate into the antenna from the brain. Their appearance in the third antennal segment is regulated by normal function of the Epidermal Growth Factor receptor and small GTPases. We denote these distinct populations of cells as Mz317-glia and GH146-glia respectively. In the adult, processes of GH146-glial cells ensheath the olfactory receptor neurons directly, while those of the Mz317-glia form a peripheral layer. Ablation of GH146-glia does not result in any significant effects on the patterning of the olfactory receptor axons. Conclusion We have demonstrated the presence of at least two distinct populations of glial cells within the Drosophila antenna. GH146-glial cells originate in the brain and migrate to the antenna along the newly formed olfactory axons. The number of cells populating the third segment of the antenna is regulated by signaling through the Epidermal Growth Factor receptor. These glia share several features of the sorting

  5. Distinct ATOH1 and Neurog3 requirements define tuft cells as a new secretory cell type in the intestinal epithelium

    NARCIS (Netherlands)

    Gerbe, F.; van Es, J.H.; Makrini, L.; Brulin, B.; Mellitzer, G.; Robine, S.; Romagnolo, B.; Shroyer, N.F.; Bourgaux, J.F.; Pignodel, C.; Clevers, H.; Jay, P.

    2011-01-01

    The unique morphology of tuft cells was first revealed by electron microscopy analyses in several endoderm-derived epithelia. Here, we explore the relationship of these cells with the other cell types of the intestinal epithelium and describe the first marker signature allowing their unambiguous

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

    Science.gov (United States)

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

    2017-11-01

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

  7. Quantifying the correlation between spatially defined oxygen gradients and cell fate in an engineered three-dimensional culture model

    OpenAIRE

    Ardakani, Amir G.; Cheema, Umber; Brown, Robert A.; Shipley, Rebecca J.

    2014-01-01

    A challenge in three-dimensional tissue culture remains the lack of quantitative information linking nutrient delivery and cellular distribution. Both in vivo and in vitro, oxygen is delivered by diffusion from its source (blood vessel or the construct margins). The oxygen level at a defined distance from its source depends critically on the balance of diffusion and cellular metabolism. Cells may respond to this oxygen environment through proliferation, death and chemotaxis, resulting in spat...

  8. 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

  9. In Plant and Animal Cells, Detergent-Resistant Membranes Do Not Define Functional Membrane Rafts

    Czech Academy of Sciences Publication Activity Database

    Tanner, W.; Malínský, Jan; Opekarová, Miroslava

    2011-01-01

    Roč. 23, č. 4 (2011), s. 1191-1193 ISSN 1040-4651 Institutional research plan: CEZ:AV0Z50390512; CEZ:AV0Z50200510 Keywords : plasma-membrane * lipod rafts * proteins Subject RIV: EA - Cell Biology Impact factor: 8.987, year: 2011

  10. Feline Neural Progenitor Cells I: Long-Term Expansion under Defined Culture Conditions

    Directory of Open Access Journals (Sweden)

    Jing Yang

    2012-01-01

    Full Text Available Neural progenitor cells (NPCs of feline origin (cNPCs have demonstrated utility in transplantation experiments, yet are difficult to grow in culture beyond the 1 month time frame. Here we use an enriched, serum-free base medium (Ultraculture and report the successful long-term propagation of these cells. Primary cultures were derived from fetal brain tissue and passaged in DMEM/F12-based or Ultraculture-based proliferation media, both in the presence of EGF + bFGF. Cells in standard DMEM/F12-based medium ceased to proliferate by 1-month, whereas the cells in the Ultraculture-based medium continued to grow for at least 5 months (end of study with no evidence of senescence. The Ultraculture-based cultures expressed lower levels of progenitor and lineage-associated markers under proliferation conditions but retained multipotency as evidenced by the ability to differentiate into neurons and glia following growth factor removal in the presence of FBS. Importantly, later passage cNPCs did not develop chromosomal aberrations.

  11. Vascular Platform to Define Hematopoietic Stem Cell Factors and Enhance Regenerative Hematopoiesis

    Directory of Open Access Journals (Sweden)

    Michael G. Poulos

    2015-11-01

    Full Text Available Hematopoietic stem cells (HSCs inhabit distinct microenvironments within the adult bone marrow (BM, which govern the delicate balance between HSC quiescence, self-renewal, and differentiation. Previous reports have proposed that HSCs localize to the vascular niche, comprised of endothelium and tightly associated perivascular cells. Herein, we examine the capacity of BM endothelial cells (BMECs to support ex vivo and in vivo hematopoiesis. We demonstrate that AKT1-activated BMECs (BMEC-Akt1 have a unique transcription factor/cytokine profile that supports functional HSCs in lieu of complex serum and cytokine supplementation. Additionally, transplantation of BMEC-Akt1 cells enhanced regenerative hematopoiesis following myeloablative irradiation. These data demonstrate that BMEC-Akt1 cultures can be used as a platform for the discovery of pro-HSC factors and justify the utility of BMECs as a cellular therapy. This technical advance may lead to the development of therapies designed to decrease pancytopenias associated with myeloablative regimens used to treat a wide array of disease states.

  12. Defining the HLA class I-associated viral antigen repertoire from HIV-1-infected human cells

    DEFF Research Database (Denmark)

    Ternette, Nicola; Yang, Hongbing; Partridge, Thomas

    2016-01-01

    Recognition and eradication of infected cells by cytotoxic T lymphocytes is a key defense mechanism against intracellular pathogens. High-throughput definition of HLA class I-associated immunopeptidomes by mass spectrometry is an increasingly important analytical tool to advance our understanding...

  13. Efficient low bandgap polymer solar cell with ordered heterojunction defined by nanoimprint lithography.

    Science.gov (United States)

    Yang, Yi; Mielczarek, Kamil; Zakhidov, Anvar; Hu, Walter

    2014-11-12

    In this work, we demonstrate the feasibility of using nanoimprint lithography (NIL) to make efficient low bandgap polymer solar cells with well-ordered heterojunction. High quality low bandgap conjugated polymer poly[2,6-(4,4-bis(2-ethylhexyl)-4H-cyclopenta[2,1-b;3,4-b']-dithiophene)-alt-4,7-(2,1,3-benzothiadiazole)] (PCPDTBT) nanogratings are fabricated using this technique for the first time. The geometry effect of PCPDTBT nanostructures on the solar cell performance is investigated by making PCPDTBT/C70 solar cells with different feature sizes of PCPDTBT nanogratings. It is found that the power conversion efficiency (PCE) increases with increasing nanograting height, PCPDTBT/C70 junction area, and decreasing nanograting width. We also find that NIL makes PCPDTBT chains interact more strongly and form an improved structural ordering. Solar cells made on the highest aspect ratio PCPDTBT nanostructures are among the best reported devices using the same material with a PCE of 5.5%.

  14. Size-defined morphotypes in Zoanthus (Hexacorallia: Zoantharia) populations on shores in KwaZulu-Natal, South Africa.

    Science.gov (United States)

    Ryland, John S

    2015-07-17

    Colonial zoanthids are a conspicuous feature of the subtropical rocky intertidal in KwaZulu-Natal but those of the genus Zoanthus have a confused taxonomy with 10, difficult to separate, nominal species described from the region. This paper presents an analysis of polyp size, measured as mean diameter determined photographically from the number of polyps occupying an area of 6 × 4 cm(2). The results, based on diameter frequency of 127 samples from five shores, indicate three populations (morphotypes) with means of 4.3 (SD ±0.53), 5.7 (SD ±0.70) and 8.4 (SD ±0.58) mm occurring in the approximate abundance ratios of 10:5:1, possibly corresponding to Zoanthus sansibaricus, Z. natalensis and Z. lawrencei. The underlying assumptions with regard to population structure (the number, size and degree of fragmentation of clones) and the normality of data are discussed, as are trans-oceanic larval dispersal, recruitment, and genetic connectivity. The essential, traditional species description in Zoanthus, using internal morphology, on its own may be an inadequate discriminator of species. The status of the few possibly valid species is discussed in relation to the present results and recent studies based on the application of molecular genetics. Thorough studies of the population structure (genets and ramets) and a taxonomic approach based on the combined use of morphology, genetic methods and statistically robust, quantitative morphometrics are proposed as a potential way forward.

  15. Predictors of Receiving a Prosthesis for Adults With Above-Knee Amputations in a Well-Defined Population.

    Science.gov (United States)

    Mundell, Benjamin F; Kremers, Hilal Maradit; Visscher, Sue; Hoppe, Kurtis M; Kaufman, Kenton R

    2016-08-01

    Prior studies have identified age as a factor in determining an individual's likelihood of receiving a prosthesis following a lower limb amputation. These studies are limited to specific subsets of the general population and are unable to account for preamputation characteristics within their study populations. Our study seeks to determine the effect of preamputation characteristics on the probability of receiving a prosthesis for the general population in the United States. To identify preamputation characteristics that predict of the likelihood of receiving a prosthesis following an above-knee amputation. A retrospective, population-based cohort study. Olmsted County, Minnesota (2010 population: 144,248). Individuals (n = 93) over the age of 18 years who underwent an above-knee amputation, that is, knee disarticulation or transfemoral amputation, while residing in Olmsted County, MN, between 1987 and 2013. Characteristics affecting the receipt of a prosthesis were analyzed using a logistic regression and a random forest algorithm for classification trees. Preamputation characteristics included age, gender, amputation etiology, year of amputation, mobility, cognitive ability, comorbidities, and time between surgery and the prosthesis decision. The association of preamputation characteristics with the receipt of a prosthesis following an above-knee amputation. Twenty-four of the participants received a prosthesis. The odds of receiving a prosthesis were almost 30 times higher in those able to walk independently prior to an amputation relative to those who could not walk independently. A 10-year increase in age was associated with a 53.8% decrease in the likelihood of being fit for a prosthesis (odds ratio = 0.462, P =.030). Time elapsed between surgery and the prosthesis decision was associated with a rise in probability of receiving a prosthesis for the first 3 months in the random forest algorithm. No other observed characteristics were associated with receipt

  16. Quantitative Analysis of Memristance Defined Exponential Model for Multi-bits Titanium Dioxide Memristor Memory Cell

    Directory of Open Access Journals (Sweden)

    DAOUD, A. A. D.

    2016-05-01

    Full Text Available The ability to store multiple bits in a single memristor based memory cell is a key feature for high-capacity memory packages. Studying multi-bit memristor circuits requires high accuracy in modelling the memristance change. A memristor model based on a novel definition of memristance is proposed. A design of a single memristor memory cell using the proposed model for the platinum electrodes titanium dioxide memristor is illustrated. A specific voltage pulse is used with varying its parameters (amplitude or pulse width to store different number of states in a single memristor. New state variation parameters associated with the utilized model are provided and their effects on write and read processes of memristive multi-states are analysed. PSPICE simulations are also held, and they show a good agreement with the data obtained from the analysis.

  17. Defining an additivity framework for mixture research in inducible whole-cell biosensors

    DEFF Research Database (Denmark)

    Martin-Betancor, K; Ritz, Christian; Fernández-Piñas, F

    2015-01-01

    A novel additivity framework for mixture effect modelling in the context of whole cell inducible biosensors has been mathematically developed and implemented in R. The proposed method is a multivariate extension of the effective dose (EDp) concept. Specifically, the extension accounts for differe......A novel additivity framework for mixture effect modelling in the context of whole cell inducible biosensors has been mathematically developed and implemented in R. The proposed method is a multivariate extension of the effective dose (EDp) concept. Specifically, the extension accounts...... for differential maximal effects among analytes and response inhibition beyond the maximum permissive concentrations. This allows a multivariate extension of Loewe additivity, enabling direct application in a biphasic dose-response framework. The proposed additivity definition was validated, and its applicability...... illustrated by studying the response of the cyanobacterial biosensor Synechococcus elongatus PCC 7942 pBG2120 to binary mixtures of Zn, Cu, Cd, Ag, Co and Hg. The novel method allowed by the first time to model complete dose-response profiles of an inducible whole cell biosensor to mixtures. In addition...

  18. A fully defined and scalable 3D culture system for human pluripotent stem cell expansion and differentiation

    Science.gov (United States)

    Lei, Yuguo; Schaffer, David V.

    2013-12-01

    Human pluripotent stem cells (hPSCs), including human embryonic stem cells and induced pluripotent stem cells, are promising for numerous biomedical applications, such as cell replacement therapies, tissue and whole-organ engineering, and high-throughput pharmacology and toxicology screening. Each of these applications requires large numbers of cells of high quality; however, the scalable expansion and differentiation of hPSCs, especially for clinical utilization, remains a challenge. We report a simple, defined, efficient, scalable, and good manufacturing practice-compatible 3D culture system for hPSC expansion and differentiation. It employs a thermoresponsive hydrogel that combines easy manipulation and completely defined conditions, free of any human- or animal-derived factors, and entailing only recombinant protein factors. Under an optimized protocol, the 3D system enables long-term, serial expansion of multiple hPSCs lines with a high expansion rate (∼20-fold per 5-d passage, for a 1072-fold expansion over 280 d), yield (∼2.0 × 107 cells per mL of hydrogel), and purity (∼95% Oct4+), even with single-cell inoculation, all of which offer considerable advantages relative to current approaches. Moreover, the system enabled 3D directed differentiation of hPSCs into multiple lineages, including dopaminergic neuron progenitors with a yield of ∼8 × 107 dopaminergic progenitors per mL of hydrogel and ∼80-fold expansion by the end of a 15-d derivation. This versatile system may be useful at numerous scales, from basic biological investigation to clinical development.

  19. Human serum-derived protein removes the need for coating in defined human pluripotent stem cell culture

    Science.gov (United States)

    Pijuan-Galitó, Sara; Tamm, Christoffer; Schuster, Jens; Sobol, Maria; Forsberg, Lars; Merry, Catherine L. R.; Annerén, Cecilia

    2016-01-01

    Reliable, scalable and time-efficient culture methods are required to fully realize the clinical and industrial applications of human pluripotent stem (hPS) cells. Here we present a completely defined, xeno-free medium that supports long-term propagation of hPS cells on uncoated tissue culture plastic. The medium consists of the Essential 8 (E8) formulation supplemented with inter-α-inhibitor (IαI), a human serum-derived protein, recently demonstrated to activate key pluripotency pathways in mouse PS cells. IαI efficiently induces attachment and long-term growth of both embryonic and induced hPS cell lines when added as a soluble protein to the medium at seeding. IαI supplementation efficiently supports adaptation of feeder-dependent hPS cells to xeno-free conditions, clonal growth as well as single-cell survival in the absence of Rho-associated kinase inhibitor (ROCKi). This time-efficient and simplified culture method paves the way for large-scale, high-throughput hPS cell culture, and will be valuable for both basic research and commercial applications. PMID:27405751

  20. Alpha- and beta-cell abnormalities in haemoglobin A1c-defined prediabetes and type 2 diabetes

    DEFF Research Database (Denmark)

    Calanna, Salvatore; Scicali, Roberto; Di Pino, Antonino

    2014-01-01

    New recommendations for the use of glycated haemoglobin A1c (HbA1c) to diagnose prediabetes and type 2 diabetes have changed the constitution of the two populations. We aimed to investigate the pathophysiological characteristics of individuals with HbA1c-defined prediabetes and type 2 diabetes......, respectively. Ten subjects with HbA1c-defined prediabetes, i.e. HbA1c from 5.7 to 6.4 % (39-46 mmol/mol), eight newly diagnosed patients with HbA1c-defined type 2 diabetes [HbA1c ≥6.5 % (≥48 mmol/mol)], and ten controls with HbA1c lower than 5.7 % (.... Subjects with HbA1c-defined prediabetes showed significantly lower insulinogenic index (P = 0.02), disposition index (P = 0.001), and glucagon suppression compared with controls; and similar (P = NS) insulinogenic index and glucagon suppression and higher disposition index (P = 0.02) compared to HbA1c...

  1. Functional heterogeneity and heritability in CHO cell populations.

    Science.gov (United States)

    Davies, Sarah L; Lovelady, Clare S; Grainger, Rhian K; Racher, Andrew J; Young, Robert J; James, David C

    2013-01-01

    In this study, we address the hypothesis that it is possible to exploit genetic/functional variation in parental Chinese hamster ovary (CHO) cell populations to isolate clonal derivatives that exhibit superior, heritable attributes for biomanufacturing--new parental cell lines which are inherently more "fit for purpose." One-hundred and ninety-nine CHOK1SV clones were isolated from a donor CHOK1SV parental population by limiting dilution cloning and microplate image analysis, followed by primary analysis of variation in cell-specific proliferation rate during extended deep-well microplate suspension culture of individual clones to accelerate genetic drift in isolated cultures. A subset of 100 clones were comparatively evaluated for transient production of a recombinant monoclonal antibody (Mab) and green fluorescent protein following transfection of a plasmid vector encoding both genes. The heritability of both cell-specific proliferation rate and Mab production was further assessed using a subset of 23 clones varying in functional capability that were subjected to cell culture regimes involving both cryopreservation and extended sub-culture. These data showed that whilst differences in transient Mab production capability were not heritable per se, clones exhibiting heritable variation in specific proliferation rate, endocytotic transfectability and N-glycan processing were identified. Finally, for clonal populations most "evolved" by extended sub-culture in vitro we investigated the relationship between cellular protein biomass content, specific proliferation rate and cell surface N-glycosylation. Rapid-specific proliferation rate was inversely correlated to CHO cell size and protein content, and positively correlated to cell surface glycan content, although substantial clone-specific variation in ability to accumulate cell biomass was evident. Taken together, our data reveal the dynamic nature of the CHO cell functional genome and the potential to evolve and

  2. Neuromuscular junction formation between human stem cell-derived motoneurons and human skeletal muscle in a defined system.

    Science.gov (United States)

    Guo, Xiufang; Gonzalez, Mercedes; Stancescu, Maria; Vandenburgh, Herman H; Hickman, James J

    2011-12-01

    Functional in vitro models composed of human cells will constitute an important platform in the next generation of system biology and drug discovery. This study reports a novel human-based in vitro Neuromuscular Junction (NMJ) system developed in a defined serum-free medium and on a patternable non-biological surface. The motoneurons and skeletal muscles were derived from fetal spinal stem cells and skeletal muscle stem cells. The motoneurons and skeletal myotubes were completely differentiated in the co-culture based on morphological analysis and electrophysiology. NMJ formation was demonstrated by phase contrast microscopy, immunocytochemistry and the observation of motoneuron-induced muscle contractions utilizing time-lapse recordings and their subsequent quenching by d-Tubocurarine. Generally, functional human based systems would eliminate the issue of species variability during the drug development process and its derivation from stem cells bypasses the restrictions inherent with utilization of primary human tissue. This defined human-based NMJ system is one of the first steps in creating functional in vitro systems and will play an important role in understanding NMJ development, in developing high information content drug screens and as test beds in preclinical studies for spinal or muscular diseases/injuries such as muscular dystrophy, Amyotrophic lateral sclerosis and spinal cord repair. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. Trail networks formed by populations of immune cells

    International Nuclear Information System (INIS)

    Yang, Taeseok Daniel; Kwon, Tae Goo; Park, Jin-sung; Lee, Kyoung J

    2014-01-01

    Populations of biological cells that communicate with each other can organize themselves to generate large-scale patterns. Examples can be found in diverse systems, ranging from developing embryos, cardiac tissues, chemotaxing ameba and swirling bacteria. The similarity, often shared by the patterns, suggests the existence of some general governing principle. On the other hand, rich diversity and system-specific properties are exhibited, depending on the type of involved cells and the nature of their interactions. The study on the similarity and the diversity constitutes a rapidly growing field of research. Here, we introduce a new class of self-organized patterns of cell populations that we term as ‘cellular trail networks’. They were observed with populations of rat microglia, the immune cells of the brain and the experimental evidence suggested that haptotaxis is the key element responsible for them. The essential features of the observed patterns are well captured by the mathematical model cells that actively crawl and interact with each other through a decomposing but non-diffusing chemical attractant laid down by the cells. Our finding suggests an unusual mechanism of socially cooperative long-range signaling for the crawling immune cells. (paper)

  4. A chemically defined culture medium containing Rho kinase inhibitor Y-27632 for the fabrication of stratified squamous epithelial cell grafts

    Energy Technology Data Exchange (ETDEWEB)

    Aslanova, Afag [Department of Surgery, Institute of Gastroenterology, Tokyo Women' s Medical University, 8-1 Kawada-cho, Shinjuku-ku, Tokyo 162-8666 (Japan); Institute of Advanced Biomedical Engineering and Science, Tokyo Women' s Medical University, TWIns, 8-1 Kawada-cho, Shinjuku-ku, Tokyo 162-8666 (Japan); Takagi, Ryo; Yamato, Masayuki; Okano, Teruo [Institute of Advanced Biomedical Engineering and Science, Tokyo Women' s Medical University, TWIns, 8-1 Kawada-cho, Shinjuku-ku, Tokyo 162-8666 (Japan); Yamamoto, Masakazu, E-mail: yamamoto.ige@twmu.ac.jp [Department of Surgery, Institute of Gastroenterology, Tokyo Women' s Medical University, 8-1 Kawada-cho, Shinjuku-ku, Tokyo 162-8666 (Japan)

    2015-05-01

    With the development of a culture method for stratified squamous epithelial cells, tissue-engineered epithelial cell sheets have been successfully applied as clinical cell grafts. However, the implementation of these cell sheets without the use of any animal-derived materials is highly desirable. In this study, Rho-associated protein kinase inhibitor Y-27632 was used to develop a chemically defined culture medium for the fabrication of stratified epithelial cell grafts consisting of human epidermal and oral keratinocytes, and the proliferation activity, cell morphology, and gene expressions of the keratinocytes were analyzed. The results of a colorimetric assay indicated that Y-27632 significantly promoted the proliferation of the keratinocytes in culture media both with and without fetal bovine serum (FBS), although there were no indications of Y-27632 efficacy on cell morphology and stratification of the keratinocytes in culture medium without any animal-derived materials. The results of quantitative RT-PCR revealed that gene expressions correlated with cell adhesion, cell–cell junction, proliferation markers, and stem/progenitor markers in cultured keratinocytes were not strongly affected by the addition of Y-27632 to the culture medium. Moreover, gene expressions of differentiation markers in stratified keratinocytes cultured in medium without FBS were nearly identical to those of keratinocytes co-cultured with 3T3 feeder cells. Interestingly, the expressions of differentiation markers in cultured stratified keratinocytes were suppressed by FBS, whereas they were reconstructed by either co-culture of a 3T3 feeder layer or addition of Y-27632 into the culture medium containing FBS. These findings indicate that Y-27632 is a useful supplement for the development of a chemically defined culture medium for fabrication of stratified epithelial cell grafts for clinical applications for the purpose of developing the culture medium with a lower risk of pathogen

  5. A chemically defined culture medium containing Rho kinase inhibitor Y-27632 for the fabrication of stratified squamous epithelial cell grafts

    International Nuclear Information System (INIS)

    Aslanova, Afag; Takagi, Ryo; Yamato, Masayuki; Okano, Teruo; Yamamoto, Masakazu

    2015-01-01

    With the development of a culture method for stratified squamous epithelial cells, tissue-engineered epithelial cell sheets have been successfully applied as clinical cell grafts. However, the implementation of these cell sheets without the use of any animal-derived materials is highly desirable. In this study, Rho-associated protein kinase inhibitor Y-27632 was used to develop a chemically defined culture medium for the fabrication of stratified epithelial cell grafts consisting of human epidermal and oral keratinocytes, and the proliferation activity, cell morphology, and gene expressions of the keratinocytes were analyzed. The results of a colorimetric assay indicated that Y-27632 significantly promoted the proliferation of the keratinocytes in culture media both with and without fetal bovine serum (FBS), although there were no indications of Y-27632 efficacy on cell morphology and stratification of the keratinocytes in culture medium without any animal-derived materials. The results of quantitative RT-PCR revealed that gene expressions correlated with cell adhesion, cell–cell junction, proliferation markers, and stem/progenitor markers in cultured keratinocytes were not strongly affected by the addition of Y-27632 to the culture medium. Moreover, gene expressions of differentiation markers in stratified keratinocytes cultured in medium without FBS were nearly identical to those of keratinocytes co-cultured with 3T3 feeder cells. Interestingly, the expressions of differentiation markers in cultured stratified keratinocytes were suppressed by FBS, whereas they were reconstructed by either co-culture of a 3T3 feeder layer or addition of Y-27632 into the culture medium containing FBS. These findings indicate that Y-27632 is a useful supplement for the development of a chemically defined culture medium for fabrication of stratified epithelial cell grafts for clinical applications for the purpose of developing the culture medium with a lower risk of pathogen

  6. Diagnostic strategies using physical examination are minimally useful in defining carpal tunnel syndrome in population-based research studies.

    Science.gov (United States)

    Descatha, A; Dale, A-M; Franzblau, A; Coomes, J; Evanoff, B

    2010-02-01

    We evaluated the utility of physical examination manoeuvres in the prediction of carpal tunnel syndrome (CTS) in a population-based research study. We studied a cohort of 1108 newly employed workers in several industries. Each worker completed a symptom questionnaire, a structured physical examination and nerve conduction study. For each hand, our CTS case definition required both median nerve conduction abnormality and symptoms classified as "classic" or "probable" on a hand diagram. We calculated the positive predictive values and likelihood ratios for physical examination manoeuvres in subjects with and without symptoms. The prevalence of CTS in our cohort was 1.2% for the right hand and 1.0% for the left hand. The likelihood ratios of a positive test for physical provocative tests ranged from 2.0 to 3.3, and those of a negative test from 0.3 to 0.9. The post-test probability of positive testing was study found that physical examination, alone or in combination with symptoms, was not predictive of CTS in a working population. We suggest using specific symptoms as a first-level screening tool, and nerve conduction study as a confirmatory test, as a case definition strategy in research settings.

  7. T cell epitopes on the 36K and 65K Mycobacterium leprae antigens defined by human T cell clones

    NARCIS (Netherlands)

    van Schooten, W. C.; Ottenhoff, T. H.; Klatser, P. R.; Thole, J.; de Vries, R. R.; Kolk, A. H.

    1988-01-01

    To identify the molecular localization and specificity of Mycobacterium leprae antigenic determinants inducing T cell activation, we studied the reactivity of M. leprae-reactive T cell clones from two tuberculoid leprosy patients towards a battery of different mycobacterial strains and purified

  8. The cancer cell map initiative: defining the hallmark networks of cancer.

    Science.gov (United States)

    Krogan, Nevan J; Lippman, Scott; Agard, David A; Ashworth, Alan; Ideker, Trey

    2015-05-21

    Progress in DNA sequencing has revealed the startling complexity of cancer genomes, which typically carry thousands of somatic mutations. However, it remains unclear which are the key driver mutations or dependencies in a given cancer and how these influence pathogenesis and response to therapy. Although tumors of similar types and clinical outcomes can have patterns of mutations that are strikingly different, it is becoming apparent that these mutations recurrently hijack the same hallmark molecular pathways and networks. For this reason, it is likely that successful interpretation of cancer genomes will require comprehensive knowledge of the molecular networks under selective pressure in oncogenesis. Here we announce the creation of a new effort, The Cancer Cell Map Initiative (CCMI), aimed at systematically detailing these complex interactions among cancer genes and how they differ between diseased and healthy states. We discuss recent progress that enables creation of these cancer cell maps across a range of tumor types and how they can be used to target networks disrupted in individual patients, significantly accelerating the development of precision medicine. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Defining the role of mesenchymal stromal cells on the regulation of matrix metalloproteinases in skeletal muscle cells

    International Nuclear Information System (INIS)

    Sassoli, Chiara; Nosi, Daniele; Tani, Alessia; Chellini, Flaminia; Mazzanti, Benedetta; Quercioli, Franco; Zecchi-Orlandini, Sandra; Formigli, Lucia

    2014-01-01

    Recent studies indicate that mesenchymal stromal cell (MSC) transplantation improves healing of injured and diseased skeletal muscle, although the mechanisms of benefit are poorly understood. In the present study, we investigated whether MSCs and/or their trophic factors were able to regulate matrix metalloproteinase (MMP) expression and activity in different cells of the muscle tissue. MSCs in co-culture with C2C12 cells or their conditioned medium (MSC-CM) up-regulated MMP-2 and MMP-9 expression and function in the myoblastic cells; these effects were concomitant with the down-regulation of the tissue inhibitor of metalloproteinases (TIMP)-1 and -2 and with increased cell motility. In the single muscle fiber experiments, MSC-CM administration increased MMP-2/9 expression in Pax-7 + satellite cells and stimulated their mobilization, differentiation and fusion. The anti-fibrotic properties of MSC-CM involved also the regulation of MMPs by skeletal fibroblasts and the inhibition of their differentiation into myofibroblasts. The treatment with SB-3CT, a potent MMP inhibitor, prevented in these cells, the decrease of α-smooth actin and type-I collagen expression induced by MSC-CM, suggesting that MSC-CM could attenuate the fibrogenic response through mechanisms mediated by MMPs. Our results indicate that growth factors and cytokines released by these cells may modulate the fibrotic response and improve the endogenous mechanisms of muscle repair/regeneration. - Highlights: • MSC-CM contains paracrine factors that up-regulate MMP expression and function in different skeletal muscle cells. • MSC-CM promotes myoblast and satellite cell migration, proliferation and differentiation. • MSC-CM negatively interferes with fibroblast-myoblast transition in primary skeletal fibroblasts. • Paracrine factors from MSCs modulate the fibrotic response and improve the endogenous mechanisms of muscle regeneration

  10. Defining the role of mesenchymal stromal cells on the regulation of matrix metalloproteinases in skeletal muscle cells

    Energy Technology Data Exchange (ETDEWEB)

    Sassoli, Chiara; Nosi, Daniele; Tani, Alessia; Chellini, Flaminia [Dept. of Experimental and Clinical Medicine—Section of Anatomy and Histology, University of Florence, Largo Brambilla, 3, 50134, Florence (Italy); Mazzanti, Benedetta [Dept. of Experimental and Clinical Medicine—Section of Haematology, University of Florence, Largo Brambilla, 3, 50134, Florence (Italy); Quercioli, Franco [CNR-National Institute of Optics (INO), Largo Enrico Fermi 6, 50125 Arcetri-Florence (Italy); Zecchi-Orlandini, Sandra [Dept. of Experimental and Clinical Medicine—Section of Anatomy and Histology, University of Florence, Largo Brambilla, 3, 50134, Florence (Italy); Formigli, Lucia, E-mail: formigli@unifi.it [Dept. of Experimental and Clinical Medicine—Section of Anatomy and Histology, University of Florence, Largo Brambilla, 3, 50134, Florence (Italy)

    2014-05-01

    Recent studies indicate that mesenchymal stromal cell (MSC) transplantation improves healing of injured and diseased skeletal muscle, although the mechanisms of benefit are poorly understood. In the present study, we investigated whether MSCs and/or their trophic factors were able to regulate matrix metalloproteinase (MMP) expression and activity in different cells of the muscle tissue. MSCs in co-culture with C2C12 cells or their conditioned medium (MSC-CM) up-regulated MMP-2 and MMP-9 expression and function in the myoblastic cells; these effects were concomitant with the down-regulation of the tissue inhibitor of metalloproteinases (TIMP)-1 and -2 and with increased cell motility. In the single muscle fiber experiments, MSC-CM administration increased MMP-2/9 expression in Pax-7{sup +} satellite cells and stimulated their mobilization, differentiation and fusion. The anti-fibrotic properties of MSC-CM involved also the regulation of MMPs by skeletal fibroblasts and the inhibition of their differentiation into myofibroblasts. The treatment with SB-3CT, a potent MMP inhibitor, prevented in these cells, the decrease of α-smooth actin and type-I collagen expression induced by MSC-CM, suggesting that MSC-CM could attenuate the fibrogenic response through mechanisms mediated by MMPs. Our results indicate that growth factors and cytokines released by these cells may modulate the fibrotic response and improve the endogenous mechanisms of muscle repair/regeneration. - Highlights: • MSC-CM contains paracrine factors that up-regulate MMP expression and function in different skeletal muscle cells. • MSC-CM promotes myoblast and satellite cell migration, proliferation and differentiation. • MSC-CM negatively interferes with fibroblast-myoblast transition in primary skeletal fibroblasts. • Paracrine factors from MSCs modulate the fibrotic response and improve the endogenous mechanisms of muscle regeneration.

  11. Cell surface antigens of radiation leukemia virus-induced BALB/c leukemias defined by syngeneic cytotoxic T lymphocytes

    International Nuclear Information System (INIS)

    Kaneko, Yukio; Oettgen, H.F.; Obata, Yuichi; Nakayama, Eiichi.

    1989-01-01

    Two cell surface antigens of mouse leukemias were defined by BALB/c cytotoxic T lymphocytes (CTL) generated against syngeneic radiation leukemia virus (RadLV)-induced leukemia, BALBRV1 or BALBRVD. Hyperimmunization of BALB/c mice with irradiated leukemias followed by in vitro sensitization of primed spleen cells resulted in the generation of CTL with high killing activity. The specificity of CTL was examined by direct cytotoxicity assays and competitive inhibition assays. A shared cell surface antigen, designated as BALBRV1 antigen, was detected by BALB/c anti-BALBRV1 CTL. BALBRV1 antigen was expressed not only on RadLV-induced BALB/c leukemias except for BALBRVD, but also on spontaneous or X-ray-induced BALB/c leukemias, chemically-induced leukemias with the H-2 d haplotype and some chemically-induced BALB/c sarcomas. In contrast, a unique cell surface antigen, designated as BALBRVD antigen, was detected by BALB/c anti-BALBRVD CTL. BALBRVD antigen was expressed only on BALBRVD, but not on thirty-nine normal lymphoid or tumor cells. These two antigens could be distinguished from those previously defined on Friend, Moloney, Rauscher or Gross murine leukemia virus (MuLV) leukemias, or MuLV-related antigens. Both cytotoxic responses were blocked by antisera against H-2K d , but not H-2D d . The relationship of BALBRV1 antigen and BALBRVD antigen to endogenous MuLV is discussed with regard to the antigenic distribution on tumor cell lines. (author)

  12. Use of flow cytometry for high-throughput cell population estimates in fixed brain tissue

    Directory of Open Access Journals (Sweden)

    Nicole A Young

    2012-07-01

    Full Text Available The numbers and types of cells in an area of cortex define its function. Therefore it is essential to characterize the numbers and distributions of total cells in areas of the cortex, as well as to identify numbers of subclasses of neurons and glial cells. To date, the large size of the primate brain and the lack of innovation in cell counting methods have been a roadblock to obtaining high-resolution maps of cell and neuron density across the cortex in humans and non-human primates. Stereological counting methods and the isotropic fractionator are valuable tools for estimating cell numbers, but are better suited to smaller, well-defined brain structures or to cortex as a whole. In the present study, we have extended our flow-cytometry based counting method, the flow fractionator (Collins et al., 2010a, to include high-throughput total cell population estimates in homogenized cortical samples. We demonstrate that our method produces consistent, accurate and repeatable cell estimates quickly. The estimates we report are in excellent agreement with estimates for the same samples obtained using a Neubauer chamber and a fluorescence microscope. We show that our flow cytometry-based method for total cell estimation in homogenized brain tissue is more efficient and more precise than manual counting methods. The addition of automated nuclei counting to our flow fractionator method allows for a fully automated, rapid characterization of total cells and neuronal and non-neuronal populations in human and non-human primate brains, providing valuable data to further our understanding of the functional organization of normal, aging and diseased brains.

  13. Spatially defined InsP3-mediated signaling in embryonic stem cell-derived cardiomyocytes.

    Directory of Open Access Journals (Sweden)

    Nidhi Kapoor

    Full Text Available The functional role of inositol 1,4,5-trisphosphate (InsP3 signaling in cardiomyocytes is not entirely understood but it was linked to an increased propensity for triggered activity. The aim of this study was to determine how InsP3 receptors can translate Ca(2+ release into a depolarization of the plasma membrane and consequently arrhythmic activity. We used embryonic stem cell-derived cardiomyocytes (ESdCs as a model system since their spontaneous electrical activity depends on InsP3-mediated Ca(2+ release. [InsP3]i was monitored with the FRET-based InsP3-biosensor FIRE-1 (Fluorescent InsP3 Responsive Element and heterogeneity in sub-cellular [InsP3]i was achieved by targeted expression of FIRE-1 in the nucleus (FIRE-1nuc or expression of InsP3 5-phosphatase (m43 localized to the plasma membrane. Spontaneous activity of ESdCs was monitored simultaneously as cytosolic Ca(2+ transients (Fluo-4/AM and action potentials (current clamp. During diastole, the diastolic depolarization was paralleled by an increase of [Ca(2+]i and spontaneous activity was modulated by [InsP3]i. A 3.7% and 1.7% increase of FIRE-1 FRET ratio and 3.0 and 1.5 fold increase in beating frequency was recorded upon stimulation with endothelin-1 (ET-1, 100 nmol/L or phenylephrine (PE, 10 µmol/L, respectively. Buffering of InsP3 by FIRE-1nuc had no effect on the basal frequency while attenuation of InsP3 signaling throughout the cell (FIRE-1, or at the plasma membrane (m43 resulted in a 53.7% and 54.0% decrease in beating frequency. In m43 expressing cells the response to ET-1 was completely suppressed. Ca(2+ released from InsP3Rs is more effective than Ca(2+ released from RyRs to enhance INCX. The results support the hypothesis that in ESdCs InsP3Rs form a functional signaling domain with NCX that translates Ca(2+ release efficiently into a depolarization of the membrane potential.

  14. Defining the Risk of Zika and Chikungunya Virus Transmission in Human Population Centers of the Eastern United States.

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    Carrie A Manore

    2017-01-01

    Full Text Available The recent spread of mosquito-transmitted viruses and associated disease to the Americas motivates a new, data-driven evaluation of risk in temperate population centers. Temperate regions are generally expected to pose low risk for significant mosquito-borne disease; however, the spread of the Asian tiger mosquito (Aedes albopictus across densely populated urban areas has established a new landscape of risk. We use a model informed by field data to assess the conditions likely to facilitate local transmission of chikungunya and Zika viruses from an infected traveler to Ae. albopictus and then to other humans in USA cities with variable human densities and seasonality. Mosquito-borne disease occurs when specific combinations of conditions maximize virus-to-mosquito and mosquito-to-human contact rates. We develop a mathematical model that captures the epidemiology and is informed by current data on vector ecology from urban sites. The model demonstrates that under specific but realistic conditions, fifty-percent of introductions by infectious travelers to a high human, high mosquito density city could initiate local transmission and 10% of the introductions could result in 100 or more people infected. Despite the propensity for Ae. albopictus to bite non-human vertebrates, we also demonstrate that local virus transmission and human outbreaks may occur when vectors feed from humans even just 40% of the time. Inclusion of human behavioral changes and mitigations were not incorporated into the models and would likely reduce predicted infections. This work demonstrates how a conditional series of non-average events can result in local arbovirus transmission and outbreaks of human disease, even in temperate cities.

  15. Defining the nature of human γδ T cells: a biographical sketch of the highly empathetic.

    Science.gov (United States)

    Kalyan, Shirin; Kabelitz, Dieter

    2013-01-01

    The elusive task of defining the character of γδ T cells has been an evolving process for immunologists since stumbling upon their existence during the molecular characterization of the α and β T cell receptor genes of their better understood brethren. Defying the categorical rules used to distinctly characterize lymphocytes as either innate or adaptive in nature, γδ T cells inhabit a hybrid world of their own. At opposing ends of the simplified spectrum of modes of antigen recognition used by lymphocytes, natural killer and αβ T cells are particularly well equipped to respond to the 'missing self' and the 'dangerous non-self', respectively. However, between these two reductive extremes, we are chronically faced with the challenge of making peace with the 'safe non-self' and dealing with the inevitable 'distressed self', and it is within this more complex realm γδ T cells excel thanks to their highly empathetic nature. This review gives an overview of the latest insights revealing the unfolding story of human γδ T cells, providing a biographical sketch of these unique lymphocytes in an attempt to capture the essence of their fundamental nature and events that influence their life trajectory. What hangs in their balance is their nuanced ability to differentiate the friends from the foe and the pathological from the benign to help us adapt swiftly and efficiently to life's many stresses.

  16. Lipidomic approach to identify patterns in phospholipid profiles and define class differences in mammary epithelial and breast cancer cells.

    Science.gov (United States)

    Dória, M Luísa; Cotrim, Zita; Macedo, Bárbara; Simões, Cláudia; Domingues, Pedro; Helguero, Luisa; Domingues, M Rosário

    2012-06-01

    Breast cancer is the leading cause of cancer-related deaths in women. Altered cellular functions of cancer cells lead to uncontrolled cellular growth and morphological changes. Cellular biomembranes are intimately involved in the regulation of cell signaling; however, they remain largely understudied. Phospholipids (PLs) are the main constituents of biological membranes and play important functional, structural and metabolic roles. The aim of this study was to establish if patterns in the PL profiles of mammary epithelial cells and breast cancer cells differ in relation to degree of differentiation and metastatic potential. For this purpose, PLs were analyzed using a lipidomic approach. In brief, PLs were extracted using Bligh and Dyer method, followed by a separation of PL classes by thin layer chromatography, and subsequent analysis by mass spectrometry (MS). Differences and similarities were found in the relative levels of PL content between mammary epithelial and breast cancer cells and between breast cancer cells with different levels of aggressiveness. When compared to the total PL content, phosphatidylcholine levels were reduced and lysophosphatydilcholines increased in the more aggressive cancer cells; while phosphatidylserine levels remained unchanged. MS analysis showed alterations in the classes of phosphatidylcholine, lysophosphatidylcholine, sphingomyelin, and phosphatidylinositides. In particular, the phosphatidylinositides, which are signaling molecules that affect proliferation, survival, and migration, showed dramatic alterations in their profile, where an increase of phosphatdylinositides saturated fatty acids chains and a decrease in C20 fatty acids in cancer cells compared with mammary epithelial cells was observed. At present, information about PL changes in cancer progression is lacking. Therefore, these data will be useful as a starting point to define possible PLs with prospective as biomarkers and disclose metabolic pathways with potential

  17. Impact of Mean Cell Hemoglobin on Hb A1c-Defined Glycemia Status.

    Science.gov (United States)

    Rodriguez-Segade, Santiago; Garcia, Javier Rodriguez; García-López, José M; Gude, Francisco; Casanueva, Felipe F; Rs-Alonso, Santiago; Camiña, Félix

    2016-12-01

    Several hematological alterations are associated with altered hemoglobin A 1c (Hb A 1c ). However, there have been no reports of their influence on the rates of exceeding standard Hb A 1c thresholds by patients for whom Hb A 1c determination is requested in clinical practice. The initial data set included the first profiles (complete blood counts, Hb A 1c , fasting glucose, and renal and hepatic parameters) of all adult patients for whom such a profile was requested between 2008 and 2013 inclusive. After appropriate exclusions, 21844 patients remained in the study. Linear and logistic regression models were adjusted for demographic, hematological, and biochemical variables excluded from the predictors. Mean corpuscular hemoglobin (MCH) and mean corpuscular volume (MCV) correlated negatively with Hb A 1c . Fasting glucose, MCH, and age emerged as predictors of Hb A 1c in a stepwise regression that discarded sex, hemoglobin, MCV, mean corpuscular hemoglobin concentration (MCHC), serum creatinine, and liver disease. Mean Hb A 1c in MCH interdecile intervals fell from 6.8% (51 mmol/mol) in the lowest (≤27.5 pg) to 6.0% (43 mmol/mol) in the highest (>32.5 pg), with similar results for MCV. After adjustment for fasting glucose and other correlates of Hb A 1c , a 1 pg increase in MCH reduced the odds of Hb A 1c -defined dysglycemia, diabetes and poor glycemia control by 10%-14%. For at least 25% of patients, low or high MCH or MCV levels are associated with increased risk of an erroneous Hb A 1c -based identification of glycemia status. Although causality has not been demonstrated, these parameters should be taken into account in interpreting Hb A 1c levels in clinical practice. © 2016 American Association for Clinical Chemistry.

  18. Destruction of radiation-resistant cell populations by hyperthermia

    International Nuclear Information System (INIS)

    Roettinger, E.M.; Gerweck, L.E.

    1979-01-01

    Animal experiments with local hyperthermia have shown that the radiauion dose necessary for the local control of 50% of the tumours examined was essentially reduced by heating to 42,5 0 C. In-vitro experients indicated selective destruction of relatively radiation-resistent cell populations by the combination of hyperthermie and reduced hydrogen ion concentration. Experiments with glioblastoma cells confirmed these results qualitatively, but showed quantitatively considerably lower sensitivity towards hyperthermia. (orig.) 891 MG/orig. 892 RDG [de

  19. The synaptic properties of cells define the hallmarks of interval timing in a recurrent neural network.

    Science.gov (United States)

    Pérez, Oswaldo; Merchant, Hugo

    2018-04-03

    Extensive research has described two key features of interval timing. The bias property is associated with accuracy and implies that time is overestimated for short intervals and underestimated for long intervals. The scalar property is linked to precision and states that the variability of interval estimates increases as a function of interval duration. The neural mechanisms behind these properties are not well understood. Here we implemented a recurrent neural network that mimics a cortical ensemble and includes cells that show paired-pulse facilitation and slow inhibitory synaptic currents. The network produces interval selective responses and reproduces both bias and scalar properties when a Bayesian decoder reads its activity. Notably, the interval-selectivity, timing accuracy, and precision of the network showed complex changes as a function of the decay time constants of the modeled synaptic properties and the level of background activity of the cells. These findings suggest that physiological values of the time constants for paired-pulse facilitation and GABAb, as well as the internal state of the network, determine the bias and scalar properties of interval timing. Significant Statement Timing is a fundamental element of complex behavior, including music and language. Temporal processing in a wide variety of contexts shows two primary features: time estimates exhibit a shift towards the mean (the bias property) and are more variable for longer intervals (the scalar property). We implemented a recurrent neural network that includes long-lasting synaptic currents, which can not only produce interval selective responses but also follow the bias and scalar properties. Interestingly, only physiological values of the time constants for paired-pulse facilitation and GABAb, as well as intermediate background activity within the network can reproduce the two key features of interval timing. Copyright © 2018 the authors.

  20. A probabilistic model for cell population phenotyping using HCS data.

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    Edouard Pauwels

    Full Text Available High Content Screening (HCS platforms allow screening living cells under a wide range of experimental conditions and give access to a whole panel of cellular responses to a specific treatment. The outcome is a series of cell population images. Within these images, the heterogeneity of cellular response to the same treatment leads to a whole range of observed values for the recorded cellular features. Consequently, it is difficult to compare and interpret experiments. Moreover, the definition of phenotypic classes at a cell population level remains an open question, although this would ease experiments analyses. In the present work, we tackle these two questions. The input of the method is a series of cell population images for which segmentation and cellular phenotype classification has already been performed. We propose a probabilistic model to represent and later compare cell populations. The model is able to fully exploit the HCS-specific information: "dependence structure of population descriptors" and "within-population variability". The experiments we carried out illustrate how our model accounts for this specific information, as well as the fact that the model benefits from considering them. We underline that these features allow richer HCS data analysis than simpler methods based on single cellular feature values averaged over each well. We validate an HCS data analysis method based on control experiments. It accounts for HCS specificities that were not taken into account by previous methods but have a sound biological meaning. Biological validation of previously unknown outputs of the method constitutes a future line of work.

  1. CXCR6, a newly defined biomarker of tissue-specific stem cell asymmetric self-renewal, identifies more aggressive human melanoma cancer stem cells.

    Directory of Open Access Journals (Sweden)

    Rouzbeh Taghizadeh

    2010-12-01

    Full Text Available A fundamental problem in cancer research is identifying the cell type that is capable of sustaining neoplastic growth and its origin from normal tissue cells. Recent investigations of a variety of tumor types have shown that phenotypically identifiable and isolable subfractions of cells possess the tumor-forming ability. In the present paper, using two lineage-related human melanoma cell lines, primary melanoma line IGR39 and its metastatic derivative line IGR37, two main observations are reported. The first one is the first phenotypic evidence to support the origin of melanoma cancer stem cells (CSCs from mutated tissue-specific stem cells; and the second one is the identification of a more aggressive subpopulation of CSCs in melanoma that are CXCR6+.We defined CXCR6 as a new biomarker for tissue-specific stem cell asymmetric self-renewal. Thus, the relationship between melanoma formation and ABCG2 and CXCR6 expression was investigated. Consistent with their non-metastatic character, unsorted IGR39 cells formed significantly smaller tumors than unsorted IGR37 cells. In addition, ABCG2+ cells produced tumors that had a 2-fold greater mass than tumors produced by unsorted cells or ABCG2- cells. CXCR6+ cells produced more aggressive tumors. CXCR6 identifies a more discrete subpopulation of cultured human melanoma cells with a more aggressive MCSC phenotype than cells selected on the basis of the ABCG2+ phenotype alone.The association of a more aggressive tumor phenotype with asymmetric self-renewal phenotype reveals a previously unrecognized aspect of tumor cell physiology. Namely, the retention of some tissue-specific stem cell attributes, like the ability to asymmetrically self-renew, impacts the natural history of human tumor development. Knowledge of this new aspect of tumor development and progression may provide new targets for cancer prevention and treatment.

  2. Label retaining cells (LRCs with myoepithelial characteristic from the proximal acinar region define stem cells in the sweat gland.

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    Yvonne Leung

    Full Text Available Slow cycling is a common feature shared among several stem cells (SCs identified in adult tissues including hair follicle and cornea. Recently, existence of unipotent SCs in basal and lumenal layers of sweat gland (SG has been described and label retaining cells (LRCs have also been localized in SGs; however, whether these LRCs possess SCs characteristic has not been investigated further. Here, we used a H2BGFP LRCs system for in vivo detection of infrequently dividing cells. This system allowed us to specifically localize and isolate SCs with label-retention and myoepithelial characteristics restricted to the SG proximal acinar region. Using an alternative genetic approach, we demonstrated that SG LRCs expressed keratin 15 (K15 in the acinar region and lineage tracing determined that K15 labeled cells contributed long term to the SG structure but not to epidermal homeostasis. Surprisingly, wound healing experiments did not activate proximal acinar SG cells to participate in epidermal healing. Instead, predominantly non-LRCs in the SG duct actively divided, whereas the majority of SG LRCs remained quiescent. However, when we further challenged the system under more favorable isolated wound healing conditions, we were able to trigger normally quiescent acinar LRCs to trans-differentiate into the epidermis and adopt its long term fate. In addition, dissociated SG cells were able to regenerate SGs and, surprisingly, hair follicles demonstrating their in vivo plasticity. By determining the gene expression profile of isolated SG LRCs and non-LRCs in vivo, we identified several Bone Morphogenetic Protein (BMP pathway genes to be up-regulated and confirmed a functional requirement for BMP receptor 1A (BMPR1A-mediated signaling in SG formation. Our data highlight the existence of SG stem cells (SGSCs and their primary importance in SG homeostasis. It also emphasizes SGSCs as an alternative source of cells in wound healing and their plasticity for

  3. Guidelines for defining and implementing standard episode of care for hematopoietic stem cell transplantation within the context of clinical trials.

    Science.gov (United States)

    Majhail, Navneet S; Giralt, Sergio; Bonagura, Anthony; Crawford, Stephen; Farnia, Stephanie; Omel, James L; Pasquini, Marcelo; Saber, Wael; LeMaistre, Charles F

    2015-04-01

    The Patient Protection and Affordable Care Act requires that health care insurers cover routine patient costs associated with participating in clinical trials for cancer and other life-threatening diseases. There is a need to better define routine costs within the context of hematopoietic stem cell transplantation (HSCT) clinical trials. This white paper presents guidance on behalf of the American Society for Blood and Marrow Transplantation for defining a standard HSCT episode and delineates components that may be considered as routine patient costs versus research costs. The guidelines will assist investigators, trial sponsors, and transplantation centers in planning for clinical trials that are conducted as a part of the HSCT episode and will inform payers who provide coverage for transplantation. Copyright © 2015 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

  4. Defined culture medium for stem cell differentiation: applicability of serum-free conditions in the mouse embryonic stem cell test.

    Science.gov (United States)

    Riebeling, Christian; Schlechter, Katharina; Buesen, Roland; Spielmann, Horst; Luch, Andreas; Seiler, Andrea

    2011-06-01

    The embryonic stem cell test (EST) is a validated method to assess the developmental toxicity potency of chemicals. It was developed to reduce animal use and allow faster testing for hazard assessment. The cells used in this method are maintained and differentiated in media containing foetal calf serum. This animal product is of considerable variation in quality, and individual batches require extensive testing for their applicability in the EST. Moreover, its production involves a large number of foetuses and possible animal suffering. We demonstrate the serum-free medium and feeder cell-free maintenance of the mouse embryonic stem cell line D3 and investigate the use of specific growth factors for induction of cardiac differentiation. Using a combination of bone morphogenetic protein-2, bone morphogenetic protein-4, activin A and ascorbic acid, embryoid bodies efficiently differentiated into contracting myocardium. Additionally, examining levels of intracellular marker proteins by flow cytometry not only confirmed differentiation into cardiomyocytes, but demonstrated significant differentiation into neuronal cells in the same time frame. Thus, this approach might allow for simultaneous detection of developmental effects on both early mesodermal and neuroectodermal differentiation. The serum-free conditions for maintenance and differentiation of D3 cells described here enhance the transferability and standardisation and hence the performance of the EST. Copyright © 2011 Elsevier Ltd. All rights reserved.

  5. The episode of genetic drift defining the migration of humans out of Africa is derived from a large east African population size.

    Directory of Open Access Journals (Sweden)

    Nuha Elhassan

    Full Text Available Human genetic variation particularly in Africa is still poorly understood. This is despite a consensus on the large African effective population size compared to populations from other continents. Based on sequencing of the mitochondrial Cytochrome C Oxidase subunit II (MT-CO2, and genome wide microsatellite data we observe evidence suggesting the effective size (Ne of humans to be larger than the current estimates, with a foci of increased genetic diversity in east Africa, and a population size of east Africans being at least 2-6 fold larger than other populations. Both phylogenetic and network analysis indicate that east Africans possess more ancestral lineages in comparison to various continental populations placing them at the root of the human evolutionary tree. Our results also affirm east Africa as the likely spot from which migration towards Asia has taken place. The study reflects the spectacular level of sequence variation within east Africans in comparison to the global sample, and appeals for further studies that may contribute towards filling the existing gaps in the database. The implication of these data to current genomic research, as well as the need to carry out defined studies of human genetic variation that includes more African populations; particularly east Africans is paramount.

  6. Steps toward Maturation of Embryonic Stem Cell-Derived Cardiomyocytes by Defined Physical Signals

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    Nian Shen

    2017-07-01

    Full Text Available Cardiovascular disease remains a leading cause of mortality and morbidity worldwide. Embryonic stem cell-derived cardiomyocytes (ESC-CMs may offer significant advances in creating in vitro cardiac tissues for disease modeling, drug testing, and elucidating developmental processes; however, the induction of ESCs to a more adult-like CM phenotype remains challenging. In this study, we developed a bioreactor system to employ pulsatile flow (1.48 mL/min, cyclic strain (5%, and extended culture time to improve the maturation of murine and human ESC-CMs. Dynamically-cultured ESC-CMs showed an increased expression of cardiac-associated proteins and genes, cardiac ion channel genes, as well as increased SERCA activity and a Raman fingerprint with the presence of maturation-associated peaks similar to primary CMs. We present a bioreactor platform that can serve as a foundation for the development of human-based cardiac in vitro models to verify drug candidates, and facilitates the study of cardiovascular development and disease.

  7. Highly defined 3D printed chitosan scaffolds featuring improved cell growth.

    Science.gov (United States)

    Elviri, Lisa; Foresti, Ruben; Bergonzi, Carlo; Zimetti, Francesca; Marchi, Cinzia; Bianchera, Annalisa; Bernini, Franco; Silvestri, Marco; Bettini, Ruggero

    2017-07-12

    The augmented demand for medical devices devoted to tissue regeneration and possessing a controlled micro-architecture means there is a need for industrial scale-up in the production of hydrogels. A new 3D printing technique was applied to the automation of a freeze-gelation method for the preparation of chitosan scaffolds with controlled porosity. For this aim, a dedicated 3D printer was built in-house: a preliminary effort has been necessary to explore the printing parameter space to optimize the printing results in terms of geometry, tolerances and mechanical properties of the product. Analysed parameters included viscosity of the starting chitosan solution, which was measured with a Brookfield viscometer, and temperature of deposition, which was determined by filming the process with a cryocooled sensor thermal camera. Optimized parameters were applied to the production of scaffolds from solutions of chitosan alone or with the addition of raffinose as a viscosity modifier. Resulting hydrogels were characterized in terms of morphology and porosity. In vitro cell culture studies comparing 3D printed scaffolds with their homologous produced by solution casting evidenced an improvement in biocompatibility deriving from the production technique as well as from the solid state modification of chitosan stemming from the addition of the viscosity modifier.

  8. Methamphetamine differentially affects BDNF and cell death factors in anatomically defined regions of the hippocampus

    Science.gov (United States)

    Galinato, Melissa H.; Orio, Laura; Mandyam, Chitra D.

    2014-01-01

    Methamphetamine exposure reduces hippocampal long-term potentiation (LTP) and neurogenesis and these alterations partially contribute to hippocampal maladaptive plasticity. The potential mechanisms underlying methamphetamine-induced maladaptive plasticity were identified in the present study. Expression of brain-derived neurotrophic factor (BDNF; a regulator of LTP and neurogenesis), and its receptor tropomyosin-related kinase B (TrkB) were studied in the dorsal and ventral hippocampal tissue lysates in rats that intravenously self-administered methamphetamine in a limited access (1 h/day) or extended access (6 h/day) paradigm for 17 days post baseline sessions. Extended access methamphetamine enhanced expression of BDNF with significant effects observed in the dorsal and ventral hippocampus. Methamphetamine-induced enhancements in BDNF expression were not associated with TrkB receptor activation as indicated by phospho (p)-TrkB-706 levels. Conversely, methamphetamine produced hypophosphorylation of NMDA receptor subunit 2B (GluN2B) at Tyr-1472 in the ventral hippocampus, indicating reduced receptor activation. In addition, methamphetamine enhanced expression of anti-apoptotic protein Bcl-2 and reduced pro-apoptotic protein Bax levels in the ventral hippocampus, suggesting a mechanism for reducing cell death. Analysis of Akt, a pro-survival kinase that suppresses apoptotic pathways and pAkt at Ser-473 demonstrated that extended access methamphetamine reduces Akt expression in the ventral hippocampus. These data reveal that alterations in Bcl-2 and Bax levels by methamphetamine were not associated with enhanced Akt expression. Given that hippocampal function and neurogenesis vary in a subregion-specific fashion, where dorsal hippocampus regulates spatial processing and has higher levels of neurogenesis, whereas ventral hippocampus regulates anxiety-related behaviors, these data suggest that methamphetamine self-administration initiates distinct allostatic changes in

  9. Functional heterogeneity of side population cells in skeletal muscle

    International Nuclear Information System (INIS)

    Uezumi, Akiyoshi; Ojima, Koichi; Fukada, So-ichiro; Ikemoto, Madoka; Masuda, Satoru; Miyagoe-Suzuki, Yuko; Takeda, Shin'ichi

    2006-01-01

    Skeletal muscle regeneration has been exclusively attributed to myogenic precursors, satellite cells. A stem cell-rich fraction referred to as side population (SP) cells also resides in skeletal muscle, but its roles in muscle regeneration remain unclear. We found that muscle SP cells could be subdivided into three sub-fractions using CD31 and CD45 markers. The majority of SP cells in normal non-regenerating muscle expressed CD31 and had endothelial characteristics. However, CD31 - CD45 - SP cells, which are a minor subpopulation in normal muscle, actively proliferated upon muscle injury and expressed not only several regulatory genes for muscle regeneration but also some mesenchymal lineage markers. CD31 - CD45 - SP cells showed the greatest myogenic potential among three SP sub-fractions, but indeed revealed mesenchymal potentials in vitro. These SP cells preferentially differentiated into myofibers after intramuscular transplantation in vivo. Our results revealed the heterogeneity of muscle SP cells and suggest that CD31 - CD45 - SP cells participate in muscle regeneration

  10. Quantitation of DNA repair in brain cell cultures: implications for autoradiographic analysis of mixed cell populations

    International Nuclear Information System (INIS)

    Dambergs, R.; Kidson, C.

    1979-01-01

    Quantitation of DNA repair in the mixed cell population of mouse embryo brain cultures has been assessed by autoradiographic analysis of unscheduled DNA synthesis following UV-irradiation. The proportion of labelled neurons and the grain density over neuronal nuclei were both less than the corresponding values for glial cells. The nuclear geometries of these two classes of cell are very different. Partial correction for the different geometries by relating grain density to nuclear area brought estimates of neuronal and glial DNA repair synthesis more closely in line. These findings have general implications for autoradiographic measurement of DNA repair in mixed cell populations and in differentiated versus dividing cells. (author)

  11. Sox2, Tlx, Gli3, and Her9 converge on Rx2 to define retinal stem cells in vivo.

    Science.gov (United States)

    Reinhardt, Robert; Centanin, Lázaro; Tavhelidse, Tinatini; Inoue, Daigo; Wittbrodt, Beate; Concordet, Jean-Paul; Martinez-Morales, Juan Ramón; Wittbrodt, Joachim

    2015-06-03

    Transcriptional networks defining stemness in adult neural stem cells (NSCs) are largely unknown. We used the proximal cis-regulatory element (pCRE) of the retina-specific homeobox gene 2 (rx2) to address such a network. Lineage analysis in the fish retina identified rx2 as marker for multipotent NSCs. rx2-positive cells located in the peripheral ciliary marginal zone behave as stem cells for the neuroretina, or the retinal pigmented epithelium. We identified upstream regulators of rx2 interrogating the rx2 pCRE in a trans-regulation screen and focused on four TFs (Sox2, Tlx, Gli3, and Her9) activating or repressing rx2 expression. We demonstrated direct interaction of the rx2 pCRE with the four factors in vitro and in vivo. By conditional mosaic gain- and loss-of-function analyses, we validated the activity of those factors on regulating rx2 transcription and consequently modulating neuroretinal and RPE stem cell features. This becomes obvious by the rx2-mutant phenotypes that together with the data presented above identify rx2 as a transcriptional hub balancing stemness of neuroretinal and RPE stem cells in the adult fish retina. © 2015 The Authors. Published under the terms of the CC BY NC ND 4.0 license.

  12. Generation of Regionally Specified Neural Progenitors and Functional Neurons from Human Embryonic Stem Cells under Defined Conditions

    Directory of Open Access Journals (Sweden)

    Agnete Kirkeby

    2012-06-01

    Full Text Available To model human neural-cell-fate specification and to provide cells for regenerative therapies, we have developed a method to generate human neural progenitors and neurons from human embryonic stem cells, which recapitulates human fetal brain development. Through the addition of a small molecule that activates canonical WNT signaling, we induced rapid and efficient dose-dependent specification of regionally defined neural progenitors ranging from telencephalic forebrain to posterior hindbrain fates. Ten days after initiation of differentiation, the progenitors could be transplanted to the adult rat striatum, where they formed neuron-rich and tumor-free grafts with maintained regional specification. Cells patterned toward a ventral midbrain (VM identity generated a high proportion of authentic dopaminergic neurons after transplantation. The dopamine neurons showed morphology, projection pattern, and protein expression identical to that of human fetal VM cells grafted in parallel. VM-patterned but not forebrain-patterned neurons released dopamine and reversed motor deficits in an animal model of Parkinson's disease.

  13. Cell mass and cell cycle dynamics of an asynchronous budding yeast population

    DEFF Research Database (Denmark)

    Lencastre Fernandes, Rita; Carlquist, Magnus; Lundin, Luisa

    2013-01-01

    of model predictions for cell property distributions against experimental data is scarce. This study focuses on the experimental and mathematical description of the dynamics of cell size and cell cycle position distributions, of a population of Saccharomyces cerevisiae, in response to the substrate...

  14. Estimating the incidence of connective tissue diseases and vasculitides in a defined population in Northern Savo area in 2010.

    Science.gov (United States)

    Elfving, P; Marjoniemi, O; Niinisalo, H; Kononoff, A; Arstila, L; Savolainen, E; Rutanen, J; Kaipiainen-Seppänen, O

    2016-07-01

    Objective of the study was to evaluate the annual incidence and distribution of autoimmune connective tissue diseases and vasculitides during 2010. All units practicing rheumatology in the Northern Savo area, Finland, participated in the study by collecting data on newly diagnosed adult patients with autoimmune connective tissue disease or vasculitis over 1-year period. Seventy-two cases with autoimmune connective tissue disease were identified. The annual incidence rates were as follows: systemic lupus erythematosus 3.4/100,000 (95 % CI 1.4-7.0), idiopathic inflammatory myopathies 1.9 (0.5-5.0), systemic sclerosis 4.4 (2.0-8.3), mixed connective tissue disease 1.0 (0.1-3.5), Sjögren's syndrome 10.7 (6.7-16.1) and undifferentiated connective tissue disease 13.6 (9.0-19.6). The annual incidence rates among vasculitis category were as follows: antineutrophil cytoplasmic antibody-associated vasculitis 1.5/100,000 (95 % CI 0.3-4.3), central nervous system vasculitis 0.5 (0-2.7) and Henoch-Schönlein purpura 1.5 (0.3-4.3). The annual incidence of giant cell arteritis in the age group of 50 years or older was 7.5/100,000 (95 % CI 3.2-14.8). The longest delay from symptom onset to diagnosis occurred in systemic sclerosis. The incidences of autoimmune connective tissue diseases and vasculitides were comparable with those in published literature. The present study showed female predominance in all connective tissue diseases, excluding idiopathic inflammatory muscle diseases and mean age at onset of disease around 50 years of age. Despite improved diagnostic tools, diagnostic delay is long especially among patients with systemic sclerosis.

  15. Transcriptional and functional differences in stem cell populations isolated from Extraocular and Limb muscles

    DEFF Research Database (Denmark)

    Pacheco-Pinedo, Eugenia Cristina; Budak, Murat T; Zeiger, Ulrike

    2008-01-01

    The extraocular muscles (EOMs) are a distinct muscle group that displays an array of unique contractile, structural and regenerative properties. They also have differential sensitivity to certain diseases and are enigmatically spared in Duchenne muscular dystrophy (DMD). The EOMs are so distinct...... from other skeletal muscles that the term: allotype has been coined to highlight EOM-group-specific properties. We hypothesized that increased and distinct stem cells may underlie the continual myogenesis noted in EOM. The side population (SP) stem cells were isolated and studied. EOMs had 15x higher...... SP cell content compared to limb muscles. Expression profiling revealed 348 transcripts that define the EOM-SP transcriptome. Over 92% of transcripts were SP-specific, as they were absent in previous whole-muscle microarray studies. Cultured EOM-SP cells revealed superior in vitro proliferative...

  16. Novel method to ascertain chromatin accessibility at specific genomic loci from frozen brain homogenates and laser capture microdissected defined cells.

    Science.gov (United States)

    Delvaux, Elaine; Mastroeni, Diego; Nolz, Jennifer; Coleman, Paul D

    2016-06-01

    We describe a novel method for assessing the "open" or "closed" state of chromatin at selected locations within the genome. This method combines the use of Benzonase, which can digest DNA in the presence of actin, with qPCR to define digested regions. We demonstrate the application of this method in brain homogenates and laser captured cells. We also demonstrate application to selected sites within more than one gene and multiple sites within one gene. We demonstrate the validity of the method by treating cells with valproate, known to render chromatin more permissive, and by comparison with classical digestion with DNase I in an in vitro preparation. Although we demonstrate the use of this method in brain tissue we also recognize its applicability to other tissue types.

  17. Novel method to ascertain chromatin accessibility at specific genomic loci from frozen brain homogenates and laser capture microdissected defined cells

    Directory of Open Access Journals (Sweden)

    Elaine Delvaux

    2016-06-01

    Full Text Available We describe a novel method for assessing the “open” or “closed” state of chromatin at selected locations within the genome. This method combines the use of Benzonase, which can digest DNA in the presence of actin, with quantitative polymerase chain reaction to define digested regions. We demonstrate the application of this method in brain homogenates and laser captured cells. We also demonstrate application to selected sites within more than 1 gene and multiple sites within 1 gene. We demonstrate the validity of the method by treating cells with valproate, known to render chromatin more permissive, and by comparison with classical digestion with DNase I in an in vitro preparation. Although we demonstrate the use of this method in brain tissue, we also recognize its applicability to other tissue types.

  18. State of the art toward defining the role of radiation therapy in the management of small cell bronchogenic carcinoma

    International Nuclear Information System (INIS)

    Salazar, O.M.; Creech, R.H.

    1980-01-01

    This review article with 70 references discusses the state of the art in defining the role of radiotherapy in managing small cell bronchogenic carcinoma (SCBC). It reviews the history of therapeutic approaches to SCBC. Several issues of particular interest to limited disease are discussed. They are: local radiation therapy for limited disease, combined radiation therapy and chemotherapy in limited disease, combination chemotherapy alone for limited disease, and an overview of the treatment of limited disease. A section on extensive disease discusses the role of radiation therapy and chemotherapy, chemotherapy only for extensive disease, and an overview of the treatment of extensive disease. An additional section discusses the use of elective brain irradiation in small cell bronchogenic carcinoma

  19. Defining a turnover index for the correlation of biomaterial degradation and cell based extracellular matrix synthesis using fluorescent tagging techniques.

    Science.gov (United States)

    Bardsley, Katie; Wimpenny, Ian; Wechsler, Roni; Shachaf, Yonatan; Yang, Ying; El Haj, Alicia J

    2016-11-01

    Non-destructive protocols which can define a biomaterial's degradation and its associated ability to support proliferation and/or promote extracellular matrix deposition will be an essential in vitro tool. In this study we investigate fluorescently tagged biomaterials, with varying rates of degradation and their ability to support cell proliferation and osteogenic differentiation. Changes in fluorescence of the biomaterials and the release of fluorescent soluble by-products were confirmed as accurate methods to quantify degradation. It was demonstrated that increasing rates of the selected biomaterials' degradation led to a decrease in cell proliferation and concurrently an increase in osteogenic matrix production. A novel turnover index (TI), which directly describes the effect of degradation of a biomaterial on cell behaviour, was calculated. Lower TIs for proliferation and high TIs for osteogenic marker production were observed on faster degrading biomaterials, indicating that these biomaterials supported an upregulation of osteogenic markers. This TI was further validated using an ex vivo chick femur model, where the faster degrading biomaterial, fibrin, led to an increased TI for mineralisation within an epiphyseal defect. This in vitro tool, TI, for monitoring the effect of biomaterial degradation on extracellular matrix production may well act as predictor of the selected biomaterials' performance during in vivo studies. This paper outlines a novel metric, Turnover Index (TI), which can be utilised in tissue-engineering for the comparison of a range of biomaterials. The metric sets out to define the relationship between the rate of degradation of biomaterials with the rate of cell proliferation and ECM synthesis, ultimately allowing us to tailor material for set clinical requirements. We have discovered some novel comparative findings that cells cultured on biomaterials with increased rates of degradation have lower rates of proliferation but alternatively

  20. A colitogenic memory CD4+ T cell population mediates gastrointestinal graft-versus-host disease

    Science.gov (United States)

    Zhou, Vivian; Agle, Kimberle; Chen, Xiao; Beres, Amy; Komorowski, Richard; Belle, Ludovic; Taylor, Carolyn; Zhu, Fenlu; Haribhai, Dipica; Williams, Calvin B.; Verbsky, James; Blumenschein, Wendy; Sadekova, Svetlana; Bowman, Eddie; Ballantyne, Christie; Weaver, Casey; Serody, David A.; Vincent, Benjamin; Serody, Jonathan; Cua, Daniel J.; Drobyski, William R.

    2016-01-01

    Damage to the gastrointestinal tract is a major cause of morbidity and mortality in graft-versus-host disease (GVHD) and is attributable to T cell–mediated inflammation. In this work, we identified a unique CD4+ T cell population that constitutively expresses the β2 integrin CD11c and displays a biased central memory phenotype and memory T cell transcriptional profile, innate-like properties, and increased expression of the gut-homing molecules α4β7 and CCR9. Using several complementary murine GVHD models, we determined that adoptive transfer and early accumulation of β2 integrin–expressing CD4+ T cells in the gastrointestinal tract initiated Th1-mediated proinflammatory cytokine production, augmented pathological damage in the colon, and increased mortality. The pathogenic effect of this CD4+ T cell population critically depended on coexpression of the IL-23 receptor, which was required for maximal inflammatory effects. Non–Foxp3-expressing CD4+ T cells produced IL-10, which regulated colonic inflammation and attenuated lethality in the absence of functional CD4+Foxp3+ T cells. Thus, the coordinate expression of CD11c and the IL-23 receptor defines an IL-10–regulated, colitogenic memory CD4+ T cell subset that is poised to initiate inflammation when there is loss of tolerance and breakdown of mucosal barriers. PMID:27500496

  1. Specific estrogen-induced cell proliferation of cultured Syrian hamster renal proximal tubular cells in serum-free chemically defined media

    International Nuclear Information System (INIS)

    Oberley, T.D.; Lauchner, L.J.; Pugh, T.D.; Gonzalez, A.; Goldfarb, S.; Li, S.A.; Li, J.J.

    1989-01-01

    It has long been recognized that the renal proximal tubular epithelium of the hamster is a bona fide estrogen target tissue. The effect of estrogens on the growth of proximal tubule cell explants and dissociated single cells derived from these explant outgrowths has been studied in culture. Renal tubular cells were grown on a PF-HR-9 basement membrane under serum-free chemically defined culture conditions. At 7-14 days in culture, cell number was enhanced 3-fold in the presence of either 17β-estradiol or diethylstilbestrol. A similar 3-fold increase in cell number was also seen at 1 nM 17β-estradiol in subcultured dissociated single tubular cells derived from hamster renal tubular explant outgrowths at 21 days in culture. Concomitant exposure of tamoxifen at 3-fold molar excess in culture completely abolished the increase in cell number seen with 17β-estradiol. The proliferation effect of estrogens on proximal tubular cell growth appears to be species specific since 17β-estradiol did not alter the growth of either rat or guinea pig proximal tubules in culture. In addition, at 7-10 days in culture in the presence of 17β-estradiol, [ 3 H]thymidine labeling of hamster tubular cells was enhanced 3-fold. These results clearly indicate that estrogens can directly induce primary epithelial cell proliferation at physiologic concentrations and provide strong additional evidence for an important hormonal role in the neoplastic transformation of the hamster kidney

  2. Well-defined block copolymers for gene delivery to dendritic cells: probing the effect of polycation chain-length.

    Science.gov (United States)

    Tang, Rupei; Palumbo, R Noelle; Nagarajan, Lakshmi; Krogstad, Emily; Wang, Chun

    2010-03-03

    The development of safe and efficient polymer carriers for DNA vaccine delivery requires mechanistic understanding of structure-function relationship of the polymer carriers and their interaction with antigen-presenting cells. Here we have synthesized a series of diblock copolymers with well-defined chain-length using atom transfer radical polymerization and characterized the influence of polycation chain-length on the physico-chemical properties of the polymer/DNA complexes as well as the interaction with dendritic cells. The copolymers consist of a hydrophilic poly(ethylene glycol) block and a cationic poly(aminoethyl methacrylate) (PAEM) block. The average degree of polymerization (DP) of the PAEM block was varied among 19, 39, and 75, with nearly uniform distribution. With increasing PAEM chain-length, polyplexes formed by the diblock copolymers and plasmid DNA had smaller average particle size and showed higher stability against electrostatic destabilization by salt and heparin. The polymers were not toxic to mouse dendritic cells (DCs) and only displayed chain-length-dependent toxicity at a high concentration (1mg/mL). In vitro gene transfection efficiency and polyplex uptake in DCs were also found to correlate with chain-length of the PAEM block with the longer polymer chain favoring transfection and cellular uptake. The polyplexes induced a modest up-regulation of surface markers for DC maturation that was not significantly dependent on PAEM chain-length. Finally, the polyplex prepared from the longest PAEM block (DP of 75) achieved an average of 20% enhancement over non-condensed anionic dextran in terms of uptake by DCs in the draining lymph nodes 24h after subcutaneous injection into mice. Insights gained from studying such structurally well-defined polymer carriers and their interaction with dendritic cells may contribute to improved design of practically useful DNA vaccine delivery systems. Copyright 2009 Elsevier B.V. All rights reserved.

  3. Defining the cellular environment in the organ of Corti following extensive hair cell loss: a basis for future sensory cell replacement in the Cochlea.

    Directory of Open Access Journals (Sweden)

    Ruth R Taylor

    Full Text Available BACKGROUND: Following the loss of hair cells from the mammalian cochlea, the sensory epithelium repairs to close the lesions but no new hair cells arise and hearing impairment ensues. For any cell replacement strategy to be successful, the cellular environment of the injured tissue has to be able to nurture new hair cells. This study defines characteristics of the auditory sensory epithelium after hair cell loss. METHODOLOGY/PRINCIPAL FINDINGS: Studies were conducted in C57BL/6 and CBA/Ca mice. Treatment with an aminoglycoside-diuretic combination produced loss of all outer hair cells within 48 hours in both strains. The subsequent progressive tissue re-organisation was examined using immunohistochemistry and electron microscopy. There was no evidence of significant de-differentiation of the specialised columnar supporting cells. Kir4.1 was down regulated but KCC4, GLAST, microtubule bundles, connexin expression patterns and pathways of intercellular communication were retained. The columnar supporting cells became covered with non-specialised cells migrating from the outermost region of the organ of Corti. Eventually non-specialised, flat cells replaced the columnar epithelium. Flat epithelium developed in distributed patches interrupting regions of columnar epithelium formed of differentiated supporting cells. Formation of the flat epithelium was initiated within a few weeks post-treatment in C57BL/6 mice but not for several months in CBA/Ca's, suggesting genetic background influences the rate of re-organisation. CONCLUSIONS/SIGNIFICANCE: The lack of dedifferentiation amongst supporting cells and their replacement by cells from the outer side of the organ of Corti are factors that may need to be considered in any attempt to promote endogenous hair cell regeneration. The variability of the cellular environment along an individual cochlea arising from patch-like generation of flat epithelium, and the possible variability between individuals

  4. Neuromuscular junction formation between human stem-cell-derived motoneurons and rat skeletal muscle in a defined system.

    Science.gov (United States)

    Guo, Xiufang; Das, Mainak; Rumsey, John; Gonzalez, Mercedes; Stancescu, Maria; Hickman, James

    2010-12-01

    To date, the coculture of motoneurons (MNs) and skeletal muscle in a defined in vitro system has only been described in one study and that was between rat MNs and rat skeletal muscle. No in vitro studies have demonstrated human MN to rat muscle synapse formation, although numerous studies have attempted to implant human stem cells into rat models to determine if they could be of therapeutic use in disease or spinal injury models, although with little evidence of neuromuscular junction (NMJ) formation. In this report, MNs differentiated from human spinal cord stem cells, together with rat skeletal myotubes, were used to build a coculture system to demonstrate that NMJ formation between human MNs and rat skeletal muscles is possible. The culture was characterized by morphology, immunocytochemistry, and electrophysiology, while NMJ formation was demonstrated by immunocytochemistry and videography. This defined system provides a highly controlled reproducible model for studying the formation, regulation, maintenance, and repair of NMJs. The in vitro coculture system developed here will be an important model system to study NMJ development, the physiological and functional mechanism of synaptic transmission, and NMJ- or synapse-related disorders such as amyotrophic lateral sclerosis, as well as for drug screening and therapy design.

  5. Quantifying the correlation between spatially defined oxygen gradients and cell fate in an engineered three-dimensional culture model.

    Science.gov (United States)

    Ardakani, Amir G; Cheema, Umber; Brown, Robert A; Shipley, Rebecca J

    2014-09-06

    A challenge in three-dimensional tissue culture remains the lack of quantitative information linking nutrient delivery and cellular distribution. Both in vivo and in vitro, oxygen is delivered by diffusion from its source (blood vessel or the construct margins). The oxygen level at a defined distance from its source depends critically on the balance of diffusion and cellular metabolism. Cells may respond to this oxygen environment through proliferation, death and chemotaxis, resulting in spatially resolved gradients in cellular density. This study extracts novel spatially resolved and simultaneous data on tissue oxygenation, cellular proliferation, viability and chemotaxis in three-dimensional spiralled, cellular collagen constructs. Oxygen concentration gradients drove preferential cellular proliferation rates and viability in the higher oxygen zones and induced chemotaxis along the spiral of the collagen construct; an oxygen gradient of 1.03 mmHg mm(-1) in the spiral direction induced a mean migratory speed of 1015 μm day(-1). Although this movement was modest, it was effective in balancing the system to a stable cell density distribution, and provided insights into the natural cell mechanism for adapting cell number and activity to a prevailing oxygen regime.

  6. Xeno-Free and Defined Human Embryonic Stem Cell-Derived Retinal Pigment Epithelial Cells Functionally Integrate in a Large-Eyed Preclinical Model

    Directory of Open Access Journals (Sweden)

    Alvaro Plaza Reyes

    2016-01-01

    Full Text Available Human embryonic stem cell (hESC-derived retinal pigment epithelial (RPE cells could replace lost tissue in geographic atrophy (GA but efficacy has yet to be demonstrated in a large-eyed model. Also, production of hESC-RPE has not yet been achieved in a xeno-free and defined manner, which is critical for clinical compliance and reduced immunogenicity. Here we describe an effective differentiation methodology using human laminin-521 matrix with xeno-free and defined medium. Differentiated cells exhibited characteristics of native RPE including morphology, pigmentation, marker expression, monolayer integrity, and polarization together with phagocytic activity. Furthermore, we established a large-eyed GA model that allowed in vivo imaging of hESC-RPE and host retina. Cells transplanted in suspension showed long-term integration and formed polarized monolayers exhibiting phagocytic and photoreceptor rescue capacity. We have developed a xeno-free and defined hESC-RPE differentiation method and present evidence of functional integration of clinically compliant hESC-RPE in a large-eyed disease model.

  7. Deletions of the long arm of chromosome 5 define subgroups of T-cell acute lymphoblastic leukemia.

    Science.gov (United States)

    La Starza, Roberta; Barba, Gianluca; Demeyer, Sofie; Pierini, Valentina; Di Giacomo, Danika; Gianfelici, Valentina; Schwab, Claire; Matteucci, Caterina; Vicente, Carmen; Cools, Jan; Messina, Monica; Crescenzi, Barbara; Chiaretti, Sabina; Foà, Robin; Basso, Giuseppe; Harrison, Christine J; Mecucci, Cristina

    2016-08-01

    Recurrent deletions of the long arm of chromosome 5 were detected in 23/200 cases of T-cell acute lymphoblastic leukemia. Genomic studies identified two types of deletions: interstitial and terminal. Interstitial 5q deletions, found in five cases, were present in both adults and children with a female predominance (chi-square, P=0.012). Interestingly, these cases resembled immature/early T-cell precursor acute lymphoblastic leukemia showing significant down-regulation of five out of the ten top differentially expressed genes in this leukemia group, including TCF7 which maps within the 5q31 common deleted region. Mutations of genes known to be associated with immature/early T-cell precursor acute lymphoblastic leukemia, i.e. WT1, ETV6, JAK1, JAK3, and RUNX1, were present, while CDKN2A/B deletions/mutations were never detected. All patients had relapsed/resistant disease and blasts showed an early differentiation arrest with expression of myeloid markers. Terminal 5q deletions, found in 18 of patients, were more prevalent in adults (chi-square, P=0.010) and defined a subgroup of HOXA-positive T-cell acute lymphoblastic leukemia characterized by 130 up- and 197 down-regulated genes. Down-regulated genes included TRIM41, ZFP62, MAPK9, MGAT1, and CNOT6, all mapping within the 1.4 Mb common deleted region at 5q35.3. Of interest, besides CNOT6 down-regulation, these cases also showed low BTG1 expression and a high incidence of CNOT3 mutations, suggesting that the CCR4-NOT complex plays a crucial role in the pathogenesis of HOXA-positive T-cell acute lymphoblastic leukemia with terminal 5q deletions. In conclusion, interstitial and terminal 5q deletions are recurrent genomic losses identifying distinct subtypes of T-cell acute lymphoblastic leukemia. Copyright© Ferrata Storti Foundation.

  8. Polarized and persistent Ca²⁺ plumes define loci for formation of wall ingrowth papillae in transfer cells.

    Science.gov (United States)

    Zhang, Hui-Ming; Imtiaz, Mohammad S; Laver, Derek R; McCurdy, David W; Offler, Christina E; van Helden, Dirk F; Patrick, John W

    2015-03-01

    Transfer cell morphology is characterized by a polarized ingrowth wall comprising a uniform wall upon which wall ingrowth papillae develop at right angles into the cytoplasm. The hypothesis that positional information directing construction of wall ingrowth papillae is mediated by Ca(2+) signals generated by spatiotemporal alterations in cytosolic Ca(2+) ([Ca(2+)]cyt) of cells trans-differentiating to a transfer cell morphology was tested. This hypothesis was examined using Vicia faba cotyledons. On transferring cotyledons to culture, their adaxial epidermal cells synchronously trans-differentiate to epidermal transfer cells. A polarized and persistent Ca(2+) signal, generated during epidermal cell trans-differentiation, was found to co-localize with the site of ingrowth wall formation. Dampening Ca(2+) signal intensity, by withdrawing extracellular Ca(2+) or blocking Ca(2+) channel activity, inhibited formation of wall ingrowth papillae. Maintenance of Ca(2+) signal polarity and persistence depended upon a rapid turnover (minutes) of cytosolic Ca(2+) by co-operative functioning of plasma membrane Ca(2+)-permeable channels and Ca(2+)-ATPases. Viewed paradermally, and proximal to the cytosol-plasma membrane interface, the Ca(2+) signal was organized into discrete patches that aligned spatially with clusters of Ca(2+)-permeable channels. Mathematical modelling demonstrated that these patches of cytosolic Ca(2+) were consistent with inward-directed plumes of elevated [Ca(2+)]cyt. Plume formation depended upon an alternating distribution of Ca(2+)-permeable channels and Ca(2+)-ATPase clusters. On further inward diffusion, the Ca(2+) plumes coalesced into a uniform Ca(2+) signal. Blocking or dispersing the Ca(2+) plumes inhibited deposition of wall ingrowth papillae, while uniform wall formation remained unaltered. A working model envisages that cytosolic Ca(2+) plumes define the loci at which wall ingrowth papillae are deposited. © The Author 2014. Published by Oxford

  9. Towards a defined ECM and small molecule based monolayer culture system for the expansion of mouse and human intestinal stem cells.

    Science.gov (United States)

    Tong, Zhixiang; Martyn, Keir; Yang, Andy; Yin, Xiaolei; Mead, Benjamin E; Joshi, Nitin; Sherman, Nicholas E; Langer, Robert S; Karp, Jeffrey M

    2018-02-01

    Current ISC culture systems face significant challenges such as animal-derived or undefined matrix compositions, batch-to-batch variability (e.g. Matrigel-based organoid culture), and complexity of assaying cell aggregates such as organoids which renders the research and clinical translation of ISCs challenging. Here, through screening for suitable ECM components, we report a defined, collagen based monolayer culture system that supports the growth of mouse and human intestinal epithelial cells (IECs) enriched for an Lgr5 + population comparable or higher to the levels found in a standard Matrigel-based organoid culture. The system, referred to as the Bolstering Lgr5 Transformational (BLT) Sandwich culture, comprises a collagen IV-coated porous substrate and a collagen I gel overlay which sandwich an IEC monolayer in between. The distinct collagen cues synergistically regulate IEC attachment, proliferation, and Lgr5 expression through maximizing the engagement of distinct cell surface adhesion receptors (i.e. integrin α2β1, integrin β4) and cell polarity. Further, we apply our BLT Sandwich system to identify that the addition of a bone morphogenetic protein (BMP) receptor inhibitor (LDN-193189) improves the expansion of Lgr5-GFP + cells from mouse small intestinal crypts by nearly 2.5-fold. Notably, the BLT Sandwich culture is capable of expanding human-derived IECs with higher LGR5 mRNA levels than conventional Matrigel culture, providing superior expansion of human LGR5 + ISCs. Considering the key roles Lgr5 + ISCs play in intestinal epithelial homeostasis and regeneration, we envision that our BLT Sandwich culture system holds great potential for understanding and manipulating ISC biology in vitro (e.g. for modeling ISC-mediated gut diseases) or for expanding a large number of ISCs for clinical utility (e.g. for stem cell therapy). Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Modeling population dynamics of mitochondria in mammalian cells

    Science.gov (United States)

    Kornick, Kellianne; Das, Moumita

    Mitochondria are organelles located inside eukaryotic cells and are essential for several key cellular processes such as energy (ATP) production, cell signaling, differentiation, and apoptosis. All organisms are believed to have low levels of variation in mitochondrial DNA (mtDNA), and alterations in mtDNA are connected to a range of human health conditions, including epilepsy, heart failure, Parkinsons disease, diabetes, and multiple sclerosis. Therefore, understanding how changes in mtDNA accumulate over time and are correlated to changes in mitochondrial function and cell properties can have a profound impact on our understanding of cell physiology and the origins of some diseases. Motivated by this, we develop and study a mathematical model to determine which cellular parameters have the largest impact on mtDNA population dynamics. The model consists of coupled ODEs to describe subpopulations of healthy and dysfunctional mitochondria subject to mitochondrial fission, fusion, autophagy, and mutation. We study the time evolution and stability of each sub-population under specific selection biases and pressures by tuning specific terms in our model. Our results may provide insights into how sub-populations of mitochondria survive and evolve under different selection pressures. This work was supported by a Grant from the Moore Foundation.

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

    Science.gov (United States)

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

    2017-03-01

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

  12. Cell population structure prior to bifurcation predicts efficiency of directed differentiation in human induced pluripotent cells.

    Science.gov (United States)

    Bargaje, Rhishikesh; Trachana, Kalliopi; Shelton, Martin N; McGinnis, Christopher S; Zhou, Joseph X; Chadick, Cora; Cook, Savannah; Cavanaugh, Christopher; Huang, Sui; Hood, Leroy

    2017-02-28

    Steering the differentiation of induced pluripotent stem cells (iPSCs) toward specific cell types is crucial for patient-specific disease modeling and drug testing. This effort requires the capacity to predict and control when and how multipotent progenitor cells commit to the desired cell fate. Cell fate commitment represents a critical state transition or "tipping point" at which complex systems undergo a sudden qualitative shift. To characterize such transitions during iPSC to cardiomyocyte differentiation, we analyzed the gene expression patterns of 96 developmental genes at single-cell resolution. We identified a bifurcation event early in the trajectory when a primitive streak-like cell population segregated into the mesodermal and endodermal lineages. Before this branching point, we could detect the signature of an imminent critical transition: increase in cell heterogeneity and coordination of gene expression. Correlation analysis of gene expression profiles at the tipping point indicates transcription factors that drive the state transition toward each alternative cell fate and their relationships with specific phenotypic readouts. The latter helps us to facilitate small molecule screening for differentiation efficiency. To this end, we set up an analysis of cell population structure at the tipping point after systematic variation of the protocol to bias the differentiation toward mesodermal or endodermal cell lineage. We were able to predict the proportion of cardiomyocytes many days before cells manifest the differentiated phenotype. The analysis of cell populations undergoing a critical state transition thus affords a tool to forecast cell fate outcomes and can be used to optimize differentiation protocols to obtain desired cell populations.

  13. An imbalance in progenitor cell populations reflects tumour progression in breast cancer primary culture models

    LENUS (Irish Health Repository)

    Donatello, Simona

    2011-04-26

    Abstract Background Many factors influence breast cancer progression, including the ability of progenitor cells to sustain or increase net tumour cell numbers. Our aim was to define whether alterations in putative progenitor populations could predict clinicopathological factors of prognostic importance for cancer progression. Methods Primary cultures were established from human breast tumour and adjacent non-tumour tissue. Putative progenitor cell populations were isolated based on co-expression or concomitant absence of the epithelial and myoepithelial markers EPCAM and CALLA respectively. Results Significant reductions in cellular senescence were observed in tumour versus non-tumour cultures, accompanied by a stepwise increase in proliferation:senescence ratios. A novel correlation between tumour aggressiveness and an imbalance of putative progenitor subpopulations was also observed. Specifically, an increased double-negative (DN) to double-positive (DP) ratio distinguished aggressive tumours of high grade, estrogen receptor-negativity or HER2-positivity. The DN:DP ratio was also higher in malignant MDA-MB-231 cells relative to non-tumourogenic MCF-10A cells. Ultrastructural analysis of the DN subpopulation in an invasive tumour culture revealed enrichment in lipofuscin bodies, markers of ageing or senescent cells. Conclusions Our results suggest that an imbalance in tumour progenitor subpopulations imbalances the functional relationship between proliferation and senescence, creating a microenvironment favouring tumour progression.

  14. Related B cell clones populate the meninges and parenchyma of patients with multiple sclerosis.

    Science.gov (United States)

    Lovato, Laura; Willis, Simon N; Rodig, Scott J; Caron, Tyler; Almendinger, Stefany E; Howell, Owain W; Reynolds, Richard; O'Connor, Kevin C; Hafler, David A

    2011-02-01

    In the central nervous system of patients with multiple sclerosis, B cell aggregates populate the meninges, raising the central question as to whether these structures relate to the B cell infiltrates found in parenchymal lesions or instead, represent a separate central nervous system immune compartment. We characterized the repertoires derived from meningeal B cell aggregates and the corresponding parenchymal infiltrates from brain tissue derived primarily from patients with progressive multiple sclerosis. The majority of expanded antigen-experienced B cell clones derived from meningeal aggregates were also present in the parenchyma. We extended this investigation to include 20 grey matter specimens containing meninges, 26 inflammatory plaques, 19 areas of normal appearing white matter and cerebral spinal fluid. Analysis of 1833 B cell receptor heavy chain variable region sequences demonstrated that antigen-experienced clones were consistently shared among these distinct compartments. This study establishes a relationship between extraparenchymal lymphoid tissue and parenchymal infiltrates and defines the arrangement of B cell clones that populate the central nervous system of patients with multiple sclerosis.

  15. Lattice Boltzmann method with the cell-population equilibrium

    International Nuclear Information System (INIS)

    Zhou Xiaoyang; Cheng Bing; Shi Baochang

    2008-01-01

    The central problem of the lattice Boltzmann method (LBM) is to construct a discrete equilibrium. In this paper, a multi-speed 1D cell-model of Boltzmann equation is proposed, in which the cell-population equilibrium, a direct non-negative approximation to the continuous Maxwellian distribution, plays an important part. By applying the explicit one-order Chapman–Enskog distribution, the model reduces the transportation and collision, two basic evolution steps in LBM, to the transportation of the non-equilibrium distribution. Furthermore, 1D dam-break problem is performed and the numerical results agree well with the analytic solutions

  16. Single-cell quantitative HER2 measurement identifies heterogeneity and distinct subgroups within traditionally defined HER2-positive patients.

    Science.gov (United States)

    Onsum, Matthew D; Geretti, Elena; Paragas, Violette; Kudla, Arthur J; Moulis, Sharon P; Luus, Lia; Wickham, Thomas J; McDonagh, Charlotte F; MacBeath, Gavin; Hendriks, Bart S

    2013-11-01

    Human epidermal growth factor receptor 2 (HER2) is an important biomarker for breast and gastric cancer prognosis and patient treatment decisions. HER2 positivity, as defined by IHC or fluorescent in situ hybridization testing, remains an imprecise predictor of patient response to HER2-targeted therapies. Challenges to correct HER2 assessment and patient stratification include intratumoral heterogeneity, lack of quantitative and/or objective assays, and differences between measuring HER2 amplification at the protein versus gene level. We developed a novel immunofluorescence method for quantitation of HER2 protein expression at the single-cell level on FFPE patient samples. Our assay uses automated image analysis to identify and classify tumor versus non-tumor cells, as well as quantitate the HER2 staining for each tumor cell. The HER2 staining level is converted to HER2 protein expression using a standard cell pellet array stained in parallel with the tissue sample. This approach allows assessment of HER2 expression and heterogeneity within a tissue section at the single-cell level. By using this assay, we identified distinct subgroups of HER2 heterogeneity within traditional definitions of HER2 positivity in both breast and gastric cancers. Quantitative assessment of intratumoral HER2 heterogeneity may offer an opportunity to improve the identification of patients likely to respond to HER2-targeted therapies. The broad applicability of the assay was demonstrated by measuring HER2 expression profiles on multiple tumor types, and on normal and diseased heart tissues. Copyright © 2013 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  17. Distinct gene regulatory programs define the inhibitory effects of liver X receptors and PPARG on cancer cell proliferation.

    Science.gov (United States)

    Savic, Daniel; Ramaker, Ryne C; Roberts, Brian S; Dean, Emma C; Burwell, Todd C; Meadows, Sarah K; Cooper, Sara J; Garabedian, Michael J; Gertz, Jason; Myers, Richard M

    2016-07-11

    The liver X receptors (LXRs, NR1H2 and NR1H3) and peroxisome proliferator-activated receptor gamma (PPARG, NR1C3) nuclear receptor transcription factors (TFs) are master regulators of energy homeostasis. Intriguingly, recent studies suggest that these metabolic regulators also impact tumor cell proliferation. However, a comprehensive temporal molecular characterization of the LXR and PPARG gene regulatory responses in tumor cells is still lacking. To better define the underlying molecular processes governing the genetic control of cellular growth in response to extracellular metabolic signals, we performed a comprehensive, genome-wide characterization of the temporal regulatory cascades mediated by LXR and PPARG signaling in HT29 colorectal cancer cells. For this analysis, we applied a multi-tiered approach that incorporated cellular phenotypic assays, gene expression profiles, chromatin state dynamics, and nuclear receptor binding patterns. Our results illustrate that the activation of both nuclear receptors inhibited cell proliferation and further decreased glutathione levels, consistent with increased cellular oxidative stress. Despite a common metabolic reprogramming, the gene regulatory network programs initiated by these nuclear receptors were widely distinct. PPARG generated a rapid and short-term response while maintaining a gene activator role. By contrast, LXR signaling was prolonged, with initial, predominantly activating functions that transitioned to repressive gene regulatory activities at late time points. Through the use of a multi-tiered strategy that integrated various genomic datasets, our data illustrate that distinct gene regulatory programs elicit common phenotypic effects, highlighting the complexity of the genome. These results further provide a detailed molecular map of metabolic reprogramming in cancer cells through LXR and PPARG activation. As ligand-inducible TFs, these nuclear receptors can potentially serve as attractive therapeutic

  18. Analyses of 123 Peripheral Human Immune Cell Subsets: Defining Differences with Age and between Healthy Donors and Cancer Patients Not Detected in Analysis of Standard Immune Cell Types

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    Lauren M. Lepone

    2016-03-01

    Full Text Available Recent advances in human immunology have led to the identification of novel immune cell subsets and the biological function of many of these subsets has now been identified. The recent US Food and Drug Administration approval of several immunotherapeutics for the treatment of a variety of cancer types and the results of ongoing immunotherapy clinical studies requires a more thorough interrogation of the immune system. We report here the use of flow cytometry-based analyses to identify 123 immune cell subsets of peripheral blood mononuclear cells. The use of these panels defines multiple differences in younger (< 40 years vs. older (≥ 40 years individuals and between aged-matched apparently healthy individuals and metastatic cancer patients, aspects not seen in the analysis of the following standard immune cell types: CD8, CD4, natural killer, natural killer-T, regulatory T, myeloid derived suppressor cells, conventional dendritic cells (DCs, plasmacytoid DCs and B cells. The use of these panels identifying 123 immune cell subsets may aid in the identification of patients who may benefit from immunotherapy, either prior to therapy or early in the immunotherapeutic regimen, for the treatment of cancer or other chronic or infectious diseases.

  19. A population-based survey of the epidemiology of symptom-defined gastroesophageal reflux disease: the Systematic Investigation of Gastrointestinal Diseases in China

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    He Jia

    2010-08-01

    Full Text Available Abstract Background The epidemiology of gastroesophageal reflux disease (GERD has yet to be investigated using the symptomatic threshold criteria recommended by the Montreal Definition. This study aimed to determine the prevalence of symptom-defined GERD across five regions of China, and to investigate variables associated with GERD. Methods A representative sample of 18 000 adults (aged 18-80 years were selected equally from rural and urban areas in each region (n = 1800. According to the Montreal Definition, GERD is present when mild symptoms of heartburn and/or regurgitation occur on ≥2 days a week, or moderate-to-severe symptoms of heartburn and/or regurgitation occur on ≥1 day a week. Results In total, 16 091 participants completed the survey (response rate: 89.4% and 16 078 responses were suitable for analysis. Applying the Montreal criteria, the prevalence of symptom-defined GERD was 3.1% and varied significantly (p Conclusions This population-based survey found that the prevalence of symptom-defined GERD in China was 3.1%, which is lower than that found in Western countries.

  20. Expression of stanniocalcin 1 in thyroid side population cells and thyroid cancer cells.

    Science.gov (United States)

    Hayase, Suguru; Sasaki, Yoshihito; Matsubara, Tsutomu; Seo, Daekwan; Miyakoshi, Masaaki; Murata, Tsubasa; Ozaki, Takashi; Kakudo, Kennichi; Kumamoto, Kensuke; Ylaya, Kris; Cheng, Sheue-yann; Thorgeirsson, Snorri S; Hewitt, Stephen M; Ward, Jerrold M; Kimura, Shioko

    2015-04-01

    Mouse thyroid side population (SP) cells consist of a minor population of mouse thyroid cells that may have multipotent thyroid stem cell characteristics. However the nature of thyroid SP cells remains elusive, particularly in relation to thyroid cancer. Stanniocalcin (STC) 1 and 2 are secreted glycoproteins known to regulate serum calcium and phosphate homeostasis. In recent years, the relationship of STC1/2 expression to cancer has been described in various tissues. Microarray analysis was carried out to determine genes up- and down-regulated in thyroid SP cells as compared with non-SP cells. Among genes up-regulated, stanniocalcin 1 (STC1) was chosen for study because of its expression in various thyroid cells by Western blotting and immunohistochemistry. Gene expression analysis revealed that genes known to be highly expressed in cancer cells and/or involved in cancer invasion/metastasis were markedly up-regulated in SP cells from both intact as well as partial thyroidectomized thyroids. Among these genes, expression of STC1 was found in five human thyroid carcinoma-derived cell lines as revealed by analysis of mRNA and protein, and its expression was inversely correlated with the differentiation status of the cells. Immunohistochemical analysis demonstrated higher expression of STC1 in the thyroid tumor cell line and thyroid tumor tissues from humans and mice. These results suggest that SP cells contain a population of cells that express genes also highly expressed in cancer cells including Stc1, which warrants further study on the role of SP cells and/or STC1 expression in thyroid cancer.

  1. Non-integrating episomal plasmid-based reprogramming of human amniotic fluid stem cells into induced pluripotent stem cells in chemically defined conditions.

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    Slamecka, Jaroslav; Salimova, Lilia; McClellan, Steven; van Kelle, Mathieu; Kehl, Debora; Laurini, Javier; Cinelli, Paolo; Owen, Laurie; Hoerstrup, Simon P; Weber, Benedikt

    2016-01-01

    Amniotic fluid stem cells (AFSC) represent an attractive potential cell source for fetal and pediatric cell-based therapies. However, upgrading them to pluripotency confers refractoriness toward senescence, higher proliferation rate and unlimited differentiation potential. AFSC were observed to rapidly and efficiently reacquire pluripotency which together with their easy recovery makes them an attractive cell source for reprogramming. The reprogramming process as well as the resulting iPSC epigenome could potentially benefit from the unspecialized nature of AFSC. iPSC derived from AFSC also have potential in disease modeling, such as Down syndrome or β-thalassemia. Previous experiments involving AFSC reprogramming have largely relied on integrative vector transgene delivery and undefined serum-containing, feeder-dependent culture. Here, we describe non-integrative oriP/EBNA-1 episomal plasmid-based reprogramming of AFSC into iPSC and culture in fully chemically defined xeno-free conditions represented by vitronectin coating and E8 medium, a system that we found uniquely suited for this purpose. The derived AF-iPSC lines uniformly expressed a set of pluripotency markers Oct3/4, Nanog, Sox2, SSEA-1, SSEA-4, TRA-1-60, TRA-1-81 in a pattern typical for human primed PSC. Additionally, the cells formed teratomas, and were deemed pluripotent by PluriTest, a global expression microarray-based in-silico pluripotency assay. However, we found that the PluriTest scores were borderline, indicating a unique pluripotent signature in the defined condition. In the light of potential future clinical translation of iPSC technology, non-integrating reprogramming and chemically defined culture are more acceptable.

  2. Multiple dendritic cell populations activate CD4+ T cells after viral stimulation.

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    Adele M Mount

    2008-02-01

    Full Text Available Dendritic cells (DC are a heterogeneous cell population that bridge the innate and adaptive immune systems. CD8alpha DC play a prominent, and sometimes exclusive, role in driving amplification of CD8(+ T cells during a viral infection. Whether this reliance on a single subset of DC also applies for CD4(+ T cell activation is unknown. We used a direct ex vivo antigen presentation assay to probe the capacity of flow cytometrically purified DC populations to drive amplification of CD4(+ and CD8(+ T cells following infection with influenza virus by different routes. This study examined the contributions of non-CD8alpha DC populations in the amplification of CD8(+ and CD4(+ T cells in cutaneous and systemic influenza viral infections. We confirmed that in vivo, effective immune responses for CD8(+ T cells are dominated by presentation of antigen by CD8alpha DC but can involve non-CD8alpha DC. In contrast, CD4(+ T cell responses relied more heavily on the contributions of dermal DC migrating from peripheral lymphoid tissues following cutaneous infection, and CD4 DC in the spleen after systemic infection. CD4(+ T cell priming by DC subsets that is dependent upon the route of administration raises the possibility that vaccination approaches could be tailored to prime helper T cell immunity.

  3. A defined co-culture of Geobacter sulfurreducens and Escherichia coli in a membrane-less microbial fuel cell.

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    Bourdakos, Nicholas; Marsili, Enrico; Mahadevan, Radhakrishnan

    2014-04-01

    Wastewater-fed microbial fuel cells (MFCs) are a promising technology to treat low-organic carbon wastewater and recover part of the chemical energy in wastewater as electrical power. However, the interactions between electrochemically active and fermentative microorganisms cannot be easily studied in wastewater-fed MFCs because of their complex microbial communities. Defined co-culture MFCs provide a detailed understanding of such interactions. In this study, we characterize the extracellular metabolites in laboratory-scale membrane-less MFCs inoculated with Geobacter sulfurreducens and Escherichia coli co-culture and compare them with pure culture MFCs. G. sulfurreducens MFCs are sparged to maintain anaerobic conditions, while co-culture MFCs rely on E. coli for oxygen removal. G. sulfurreducens MFCs have a power output of 128 mW m(-2) , compared to 63 mW m(-2) from the co-culture MFCs. Analysis of metabolites shows that succinate production in co-culture MFCs decreases current production by G. sulfurreducens and that the removal of succinate is responsible for the increased current density in the late co-culture MFCs. Interestingly, pH adjustment is not required for co-culture MFCs but a base addition is necessary for E. coli MFCs and cultures in vials. Our results show that defined co-culture MFCs provide clear insights into metabolic interactions among bacteria while maintaining a low operational complexity. © 2013 Wiley Periodicals, Inc.

  4. Population genetics inside a cell: Mutations and mitochondrial genome maintenance

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    Goyal, Sidhartha; Shraiman, Boris; Gottschling, Dan

    2012-02-01

    In realistic ecological and evolutionary systems natural selection acts on multiple levels, i.e. it acts on individuals as well as on collection of individuals. An understanding of evolutionary dynamics of such systems is limited in large part due to the lack of experimental systems that can challenge theoretical models. Mitochondrial genomes (mtDNA) are subjected to selection acting on cellular as well as organelle levels. It is well accepted that mtDNA in yeast Saccharomyces cerevisiae is unstable and can degrade over time scales comparable to yeast cell division time. We utilize a recent technology designed in Gottschling lab to extract DNA from populations of aged yeast cells and deep sequencing to characterize mtDNA variation in a population of young and old cells. In tandem, we developed a stochastic model that includes the essential features of mitochondrial biology that provides a null model for expected mtDNA variation. Overall, we find approximately 2% of the polymorphic loci that show significant increase in frequency as cells age providing direct evidence for organelle level selection. Such quantitative study of mtDNA dynamics is absolutely essential to understand the propagation of mtDNA mutations linked to a spectrum of age-related diseases in humans.

  5. Mosaic Expression of Thyroid Hormone Regulatory Genes Defines Cell Type-Specific Dependency in the Developing Chicken Cerebellum.

    Science.gov (United States)

    Delbaere, Joke; Van Herck, Stijn L J; Bourgeois, Nele M A; Vancamp, Pieter; Yang, Shuo; Wingate, Richard J T; Darras, Veerle M

    2016-12-01

    The cerebellum is a morphologically unique brain structure that requires thyroid hormones (THs) for the correct coordination of key cellular events driving its development. Unravelling the interplay between the multiple factors that can regulate intracellular TH levels is a key step to understanding their role in the regulation of these cellular processes. We therefore investigated the regional/cell-specific expression pattern of TH transporters and deiodinases in the cerebellum using the chicken embryo as a model. In situ hybridisation revealed expression of the TH transporters monocarboxylate transporter 8 (MCT8) and 10 (MCT10), L-type amino acid transporter 1 (LAT1) and organic anion transporting polypeptide 1C1 (OATP1C1) as well as the inactivating type 3 deiodinase (D3) in the fourth ventricle choroid plexus, suggesting a possible contribution of the resulting proteins to TH exchange and subsequent inactivation of excess hormone at the blood-cerebrospinal fluid barrier. Exclusive expression of LAT1 and the activating type 2 deiodinase (D2) mRNA was found at the level of the blood-brain barrier, suggesting a concerted function for LAT1 and D2 in the direct access of active T 3 to the developing cerebellum via the capillary endothelial cells. The presence of MCT8 mRNA in Purkinje cells and cerebellar nuclei during the first 2 weeks of embryonic development points to a potential role of this transporter in the uptake of T 3 in central neurons. At later stages, together with MCT10, detection of MCT8 signal in close association with the Purkinje cell dendritic tree suggests a role of both transporters in TH signalling during Purkinje cell synaptogenesis. MCT10 was also expressed in late-born cells in the rhombic lip lineage with a clear hybridisation signal in the outer external granular layer, indicating a potential role for MCT10 in the proliferation of granule cell precursors. By contrast, expression of D3 in the first-born rhombic lip-derived population may

  6. Carrier population control and surface passivation in solar cells

    KAUST Repository

    Cuevas, Andres

    2018-05-02

    Controlling the concentration of charge carriers near the surface is essential for solar cells. It permits to form regions with selective conductivity for either electrons or holes and it also helps to reduce the rate at which they recombine. Chemical passivation of the surfaces is equally important, and it can be combined with population control to implement carrier-selective, passivating contacts for solar cells. This paper discusses different approaches to suppress surface recombination and to manipulate the concentration of carriers by means of doping, work function and charge. It also describes some of the many surface-passivating contacts that are being developed for silicon solar cells, restricted to experiments performed by the authors.

  7. Modelling cell population growth with applications to cancer therapy in human tumour cell lines.

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    Basse, Britta; Baguley, Bruce C; Marshall, Elaine S; Wake, Graeme C; Wall, David J N

    2004-01-01

    In this paper we present an overview of the work undertaken to model a population of cells and the effects of cancer therapy. We began with a theoretical one compartment size structured cell population model and investigated its asymptotic steady size distributions (SSDs) (On a cell growth model for plankton, MMB JIMA 21 (2004) 49). However these size distributions are not similar to the DNA (size) distributions obtained experimentally via the flow cytometric analysis of human tumour cell lines (data obtained from the Auckland Cancer Society Research Centre, New Zealand). In our one compartment model, size was a generic term, but in order to obtain realistic steady size distributions we chose size to be DNA content and devised a multi-compartment mathematical model for the cell division cycle where each compartment corresponds to a distinct phase of the cell cycle (J. Math. Biol. 47 (2003) 295). We then incorporated another compartment describing the possible induction of apoptosis (cell death) from mitosis phase (Modelling cell death in human tumour cell lines exposed to anticancer drug paclitaxel, J. Math. Biol. 2004, in press). This enabled us to compare our model to flow cytometric data of a melanoma cell line where the anticancer drug, paclitaxel, had been added. The model gives a dynamic picture of the effects of paclitaxel on the cell cycle. We hope to use the model to describe the effects of other cancer therapies on a number of different cell lines. Copyright 2004 Elsevier Ltd.

  8. Influence of Cell-Cell Interactions on the Population Growth Rate in a Tumor

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    Chen, Yong

    2017-12-01

    The understanding of the macroscopic phenomenological models of the population growth at a microscopic level is important to predict the population behaviors emerged from the interactions between the individuals. In this work, we consider the influence of the population growth rate R on the cell-cell interaction in a tumor system and show that, in most cases especially small proliferative probabilities, the regulative role of the interaction will be strengthened with the decline of the intrinsic proliferative probabilities. For the high replication rates of an individual and the cooperative interactions, the proliferative probability almost has no effect. We compute the dependences of R on the interactions between the cells under the approximation of the nearest neighbor in the rim of an avascular tumor. Our results are helpful to qualitatively understand the influence of the interactions between the individuals on the growth rate in population systems. Supported by the National Natural Science Foundation of China under Grant Nos. 11675008 and 21434001

  9. Establishment and Characterization of a Highly Tumourigenic and Cancer Stem Cell Enriched Pancreatic Cancer Cell Line as a Well Defined Model System

    Science.gov (United States)

    Fredebohm, Johannes; Boettcher, Michael; Eisen, Christian; Gaida, Matthias M.; Heller, Anette; Keleg, Shereen; Tost, Jörg; Greulich-Bode, Karin M.; Hotz-Wagenblatt, Agnes; Lathrop, Mark; Giese, Nathalia A.; Hoheisel, Jörg D.

    2012-01-01

    Standard cancer cell lines do not model the intratumoural heterogeneity situation sufficiently. Clonal selection leads to a homogeneous population of cells by genetic drift. Heterogeneity of tumour cells, however, is particularly critical for therapeutically relevant studies, since it is a prerequisite for acquiring drug resistance and reoccurrence of tumours. Here, we report the isolation of a highly tumourigenic primary pancreatic cancer cell line, called JoPaca-1 and its detailed characterization at multiple levels. Implantation of as few as 100 JoPaca-1 cells into immunodeficient mice gave rise to tumours that were histologically very similar to the primary tumour. The high heterogeneity of JoPaca-1 was reflected by diverse cell morphology and a substantial number of chromosomal aberrations. Comparative whole-genome sequencing of JoPaca-1 and BxPC-3 revealed mutations in genes frequently altered in pancreatic cancer. Exceptionally high expression of cancer stem cell markers and a high clonogenic potential in vitro and in vivo was observed. All of these attributes make this cell line an extremely valuable model to study the biology of and pharmaceutical effects on pancreatic cancer. PMID:23152778

  10. Investigating energy deposition within cell populations using Monte Carlo simulations.

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    Oliver, Patricia A K; Thomson, Rowan M

    2018-06-27

    In this work, we develop multicellular models of healthy and cancerous human soft tissues, which are used to investigate energy deposition in subcellular targets, quantify the microdosimetric spread in a population of cells, and determine how these results depend on model details. Monte Carlo (MC) tissue models combining varying levels of detail on different length scales are developed: microscopically-detailed regions of interest (>1500 explicitly-modelled cells) are embedded in bulk tissue phantoms irradiated by photons (20 keV to 1.25 MeV). Specific energy (z; energy imparted per unit mass) is scored in nuclei and cytoplasm compartments using the EGSnrc user-code egs_chamber; specific energy mean, <z>, standard deviation, σz, and distribution, f(z,D), are calculated for a variety of macroscopic doses, D. MC-calculated f(z,D) are compared with normal distributions having the same mean and standard deviation. For mGy doses, there is considerable variation in energy deposition (microdosimetric spread) throughout a cell population: e.g., for 30 keV photons irradiating melanoma with 7.5 μm cell radius and 3 μm nuclear radius, σz/<z> for nuclear targets is 170%, and the fraction of nuclei receiving no energy deposition, fz=0, is 0.31 for a dose of 10 mGy. If cobalt-60 photons are considered instead, then σz/<z> decreases to 84%, and fz=0 decreases to 0.036. These results correspond to randomly arranged cells with cell/nucleus sizes randomly sampled from a normal distribution with a standard deviation of 1 μm. If cells are arranged in a hexagonal lattice and cell/nucleus sizes are uniform throughout the population, then σz/<z> decreases to 106% and 68% for 30 keV and cobalt-60,respectively; fz=0

  11. Six host range variants of the xenotropic/polytropic gammaretroviruses define determinants for entry in the XPR1 cell surface receptor

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    Kozak Christine A

    2009-10-01

    Full Text Available Abstract Background The evolutionary interactions between retroviruses and their receptors result in adaptive selection of restriction variants that can allow natural populations to evade retrovirus infection. The mouse xenotropic/polytropic (X/PMV gammaretroviruses rely on the XPR1 cell surface receptor for entry into host cells, and polymorphic variants of this receptor have been identified in different rodent species. Results We screened a panel of X/PMVs for infectivity on rodent cells carrying 6 different XPR1 receptor variants. The X/PMVs included 5 well-characterized laboratory and wild mouse virus isolates as well as a novel cytopathic XMV-related virus, termed Cz524, isolated from an Eastern European wild mouse-derived strain, and XMRV, a xenotropic-like virus isolated from human prostate cancer. The 7 viruses define 6 distinct tropisms. Cz524 and another wild mouse isolate, CasE#1, have unique species tropisms. Among the PMVs, one Friend isolate is restricted by rat cells. Among the XMVs, two isolates, XMRV and AKR6, differ from other XMVs in their PMV-like restriction in hamster cells. We generated a set of Xpr1 mutants and chimeras, and identified critical amino acids in two extracellular loops (ECLs that mediate entry of these different viruses, including 3 residues in ECL3 that are involved in PMV entry (E500, T507, and V508 and can also influence infectivity by AKR6 and Cz524. Conclusion We used a set of natural variants and mutants of Xpr1 to define 6 distinct host range variants among naturally occurring X/PMVs (2 XMV variants, 2 PMVs, 2 different wild mouse variants. We identified critical amino acids in XPR1 that mediate entry of these viruses. These gammaretroviruses and their XPR1 receptor are thus highly functionally polymorphic, a consequence of the evolutionary pressures that favor both host resistance and virus escape mutants. This variation accounts for multiple naturally occurring virus resistance phenotypes and

  12. Efficient generation of transgene- and feeder-free induced pluripotent stem cells from human dental mesenchymal stem cells and their chemically defined differentiation into cardiomyocytes.

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    Tan, Xiaobing; Dai, Qingli; Guo, Tao; Xu, Jingshu; Dai, Qingyuan

    2018-01-22

    Advance in stem cell research resulted in several processes to generate induced pluripotent stem cells (iPSCs) from adult somatic cells. In our previous study, the reprogramming of iPSCs from human dental mesenchymal stem cells (MSCs) including SCAP and DPSCs, has been reported. Herein, safe iPSCs were reprogrammed from SCAP and DPSCs using non-integrating RNA virus vector, which is an RNA virus carrying no risk of altering host genome. DPSCs- and SCAP-derived iPSCs exhibited the characteristics of the classical morphology with human embryonic stem cells (hESCs) without integration of foreign genes, indicating the potential of their clinical application. Moreover, induced PSCs showed the capacity of self-renewal and differentiation into cardiac myocytes. We have achieved the differentiation of hiPSCs to cardiomyocytes lineage under serum and feeder-free conditions, using a chemically defined medium CDM3. In CDM3, hiPSCs differentiation is highly generating cardiomyocytes. The results showed this protocol produced contractile sheets of up to 97.2% TNNT2 cardiomyocytes after purification. Furthermore, derived hiPSCs differentiated to mature cells of the three embryonic germ layers in vivo and in vitro of beating cardiomyocytes. The above whole protocol enables the generation of large scale of highly pure cardiomyocytes as needed for cellular therapy. Copyright © 2017. Published by Elsevier Inc.

  13. Microcontact printing of polydopamine on thermally expandable hydrogels for controlled cell adhesion and delivery of geometrically defined microtissues.

    Science.gov (United States)

    Lee, Yu Bin; Kim, Se-Jeong; Kim, Eum Mi; Byun, Hayeon; Chang, Hyung-Kwan; Park, Jungyul; Choi, Yu Suk; Shin, Heungsoo

    2017-10-01

    Scaffold-free harvest of microtissue with a defined structure has received a great deal of interest in cell-based assay and regenerative medicine. In this study, we developed thermally expandable hydrogels with spatially controlled cell adhesive patterns for rapid harvest of geometrically controlled microtissue. We patterned polydopamine (PD) on to the hydrogel via microcontact printing (μCP), in linear shapes with widths of 50, 100 and 200μm. The hydrogels facilitated formation of spatially controlled strip-like microtissue of human dermal fibroblasts (HDFBs). It was possible to harvest and translocate microtissues with controlled widths of 61.4±14.7, 104.3±15.6, and 186.6±22.3μm from the hydrogel to glass substrates by conformal contact upon expansion of the hydrogel in response to a temperature change from 37 to 4°C, preserving high viability, extracellular matrix, and junction proteins. Microtissues were readily translocated in vivo to the subcutaneous tissue of mouse. The microtissues were further utilized as a simple assay model for monitoring of contraction in response to ROCK1 inhibitor. Collectively, micro-sized patterning of PD on the thermally expandable hydrogels via μCP holds promise for the development of microtissue harvesting systems that can be employed to ex vivo tissue assay and cell-based therapy. Harvest of artificial tissue with controlled cellular arrangement independently from external materials has been widely studied in cell-based assay and regenerative medicine. In this study, we developed scaffold-free harvest system of microtissues with anisotropic arrangement and controlled width by exploiting thermally expandable hydrogels with cell-adhesive patterns of polydopamine formed by simple microcontact printing. Cultured strips of human dermal fibroblasts on the hydrogels were rapidly delivered to various targets ranging from flat coverglass to mice subcutaneous tissue by thermal expansion of the hydrogel at 4°C for 10min. These

  14. Diets and selected lifestyle practices of self-defined adult vegetarians from a population-based sample suggest they are more 'health conscious'

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    Barr Susan I

    2005-04-01

    Full Text Available Abstract Background Few population-based studies of vegetarians have been published. Thus we compared self-reported vegetarians to non-vegetarians in a representative sample of British Columbia (BC adults, weighted to reflect the BC population. Methods Questionnaires, 24-hr recalls and anthropometric measures were completed during in-person interviews with 1817 community-dwelling residents, 19–84 years, recruited using a population-based health registry. Vegetarian status was self-defined. ANOVA with age as a covariate was used to analyze continuous variables, and chi-square was used for categorical variables. Supplement intakes were compared using the Mann-Whitney test. Results Approximately 6% (n = 106 stated that they were vegetarian, and most did not adhere rigidly to a flesh-free diet. Vegetarians were more likely female (71% vs. 49%, single, of low-income status, and tended to be younger. Female vegetarians had lower BMI than non-vegetarians (23.1 ± 0.7 (mean ± SE vs. 25.7 ± 0.2 kg/m2, and also had lower waist circumference (75.0 ± 1.5 vs. 79.8 ± 0.5 cm. Male vegetarians and non-vegetarians had similar BMI (25.9 ± 0.8 vs. 26.7 ± 0.2 kg/m2 and waist circumference (92.5 ± 2.3 vs. 91.7 ± 0.4 cm. Female vegetarians were more physically active (69% vs. 42% active ≥4/wk while male vegetarians were more likely to use nutritive supplements (71% vs. 51%. Energy intakes were similar, but vegetarians reported higher % energy as carbohydrate (56% vs. 50%, and lower % protein (men only; 13% vs. 17% or % fat (women only; 27% vs. 33%. Vegetarians had higher fiber, magnesium and potassium intakes. For several other nutrients, differences by vegetarian status differed by gender. The prevalence of inadequate magnesium intake (% below Estimated Average Requirement was lower in vegetarians than non-vegetarians (15% vs. 34%. Female vegetarians also had a lower prevalence of inadequate thiamin, folate, vitamin B6 and C intakes. Vegetarians were

  15. Population transcriptomics with single-cell resolution: a new field made possible by microfluidics: a technology for high throughput transcript counting and data-driven definition of cell types.

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    Plessy, Charles; Desbois, Linda; Fujii, Teruo; Carninci, Piero

    2013-02-01

    Tissues contain complex populations of cells. Like countries, which are comprised of mixed populations of people, tissues are not homogeneous. Gene expression studies that analyze entire populations of cells from tissues as a mixture are blind to this diversity. Thus, critical information is lost when studying samples rich in specialized but diverse cells such as tumors, iPS colonies, or brain tissue. High throughput methods are needed to address, model and understand the constitutive and stochastic differences between individual cells. Here, we describe microfluidics technologies that utilize a combination of molecular biology and miniaturized labs on chips to study gene expression at the single cell level. We discuss how the characterization of the transcriptome of each cell in a sample will open a new field in gene expression analysis, population transcriptomics, that will change the academic and biomedical analysis of complex samples by defining them as quantified populations of single cells. Copyright © 2013 WILEY Periodicals, Inc.

  16. Two functional motifs define the interaction, internalization and toxicity of the cell-penetrating antifungal peptide PAF26 on fungal cells.

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    Alberto Muñoz

    Full Text Available The synthetic, cell penetrating hexapeptide PAF26 (RKKWFW is antifungal at low micromolar concentrations and has been proposed as a model for cationic, cell-penetrating antifungal peptides. Its short amino acid sequence facilitates the analysis of its structure-activity relationships using the fungal models Neurospora crassa and Saccharomyces cerevisiae, and human and plant pathogens Aspergillus fumigatus and Penicillium digitatum, respectively. Previously, PAF26 at low fungicidal concentrations was shown to be endocytically internalized, accumulated in vacuoles and then actively transported into the cytoplasm where it exerts its antifungal activity. In the present study, two PAF26 derivatives, PAF95 (AAAWFW and PAF96 (RKKAAA, were designed to characterize the roles of the N-terminal cationic and the C-terminal hydrophobic motifs in PAF26's mode-of-action. PAF95 and PAF96 exhibited substantially reduced antifungal activity against all the fungi analyzed. PAF96 localized to fungal cell envelopes and was not internalized by the fungi. In contrast, PAF95 was taken up into vacuoles of N. crassa, wherein it accumulated and was trapped without toxic effects. Also, the PAF26 resistant Δarg1 strain of S. cerevisiae exhibited increased PAF26 accumulation in vacuoles. Live-cell imaging of GFP-labelled nuclei in A. fumigatus showed that transport of PAF26 from the vacuole to the cytoplasm was followed by nuclear breakdown and dissolution. This work demonstrates that the amphipathic PAF26 possesses two distinct motifs that allow three stages in its antifungal action to be defined: (i its interaction with the cell envelope; (ii its internalization and transport to vacuoles mediated by the aromatic hydrophobic domain; and (iii its transport from vacuoles to the cytoplasm. Significantly, cationic residues in PAF26 are important not only for the electrostatic attraction and interaction with the fungal cell but also for transport from the vacuole to the

  17. Supraspliceosomes at Defined Functional States Portray the Pre-Assembled Nature of the Pre-mRNA Processing Machine in the Cell Nucleus

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    Hani Kotzer-Nevo

    2014-06-01

    Full Text Available When isolated from mammalian cell nuclei, all nuclear pre-mRNAs are packaged in multi-subunit large ribonucleoprotein complexes—supraspliceosomes—composed of four native spliceosomes interconnected by the pre-mRNA. Supraspliceosomes contain all five spliceosomal U snRNPs, together with other splicing factors, and are functional in splicing. Supraspliceosomes studied thus far represent the steady-state population of nuclear pre-mRNAs that were isolated at different stages of the splicing reaction. To analyze specific splicing complexes, here, we affinity purified Pseudomonas aeruginosa phage 7 (PP7-tagged splicing complexes assembled in vivo on Adenovirus Major Late (AdML transcripts at specific functional stages, and characterized them using molecular techniques including mass spectrometry. First, we show that these affinity purified splicing complexes assembled on PP7-tagged AdML mRNA or on PP7-tagged AdML pre-mRNA are assembled in supraspliceosomes. Second, similar to the general population of supraspliceosomes, these defined supraspliceosomes populations are assembled with all five U snRNPs at all splicing stages. This study shows that dynamic changes in base-pairing interactions of U snRNA:U snRNA and U snRNA:pre-mRNA that occur in vivo during the splicing reaction do not require changes in U snRNP composition of the supraspliceosome. Furthermore, there is no need to reassemble a native spliceosome for the splicing of each intron, and rearrangements of the interactions will suffice.

  18. CELL POPULATION KINETICS OF EXCISED ROOTS OF PISUM SATIVUM

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    Van't Hof, Jack

    1965-01-01

    The cell population kinetics of excised, cultured pea roots was studied with the use of tritiated thymidine and colchicine to determine (1) the influence of excision, (2) the influence of sucrose concentration, (3) the average mitotic cycle duration, and (4) the duration of mitosis and the G 1, S, and G 2 periods of interphase.1 The results indicate that the process of excision causes a drop in the frequency of mitotic figures when performed either at the beginning of the culture period or after 100 hours in culture. This initial decrease in frequency of cell division is independent of sucrose concentration, but the subsequent rise in frequency of division, after 12 hours in culture, is dependent upon sucrose concentration. Two per cent sucrose maintains the shortest mitotic cycle duration. The use of colchicine indicated an average cycle duration of 20 hours, whereas the use of tritiated thymidine produced an average cycle duration of 17 hours. PMID:5857253

  19. Quantitative changes of main components of erythrocyte membranes which define architectonics of cells under pttg gene knockout

    Directory of Open Access Journals (Sweden)

    О. P. Kanyuka

    2014-04-01

    Full Text Available A pttg gene knockout affects the functional state of erythron in mice which could be associated with structural changes in the structure of erythrocyte membranes. The pttg gene knockout causes a significant modification of fatty acids composition of erythrocyte membrane lipids by reducing the content of palmitic acid and increasing of polyunsaturated fatty acids amount by 18%. Analyzing the erythrocyte surface architectonics of mice under pttg gene knockout, it was found that on the background of reduction of the functionally complete biconcave discs population one could observe an increase of the number of transformed cells at different degeneration stages. Researches have shown that in mice with a pttg gene knockout compared with a control group of animals cytoskeletal protein – β-spectrin was reduced by 17.03%. However, there is a reduction of membrane protein band 3 by 33.04%, simultaneously the content of anion transport protein band 4.5 increases by 35.2% and protein band 4.2 by 32.1%. The lectin blot analysis has helped to reveal changes in the structure of the carbohydrate determinants of ery­throcyte membrane glycoproteins under conditions of directed pttg gene inactivation, accompanied by changes in the type of communication, which joins the terminal residue in carbohydrate determinant of glycoproteins. Thus, a significant redistribution of protein and fatty acids contents in erythrocyte membranes that manifested in the increase of the deformed shape of red blood cells is observed under pttg gene knockout.

  20. Decoherence in yeast cell populations and its implications for genome-wide expression noise.

    Science.gov (United States)

    Briones, M R S; Bosco, F

    2009-01-20

    Gene expression "noise" is commonly defined as the stochastic variation of gene expression levels in different cells of the same population under identical growth conditions. Here, we tested whether this "noise" is amplified with time, as a consequence of decoherence in global gene expression profiles (genome-wide microarrays) of synchronized cells. The stochastic component of transcription causes fluctuations that tend to be amplified as time progresses, leading to a decay of correlations of expression profiles, in perfect analogy with elementary relaxation processes. Measuring decoherence, defined here as a decay in the auto-correlation function of yeast genome-wide expression profiles, we found a slowdown in the decay of correlations, opposite to what would be expected if, as in mixing systems, correlations decay exponentially as the equilibrium state is reached. Our results indicate that the populational variation in gene expression (noise) is a consequence of temporal decoherence, in which the slow decay of correlations is a signature of strong interdependence of the transcription dynamics of different genes.

  1. No association of defined variability in leptin, leptin receptor, adiponectin, proopiomelanocortin and ghrelin gene with food preferences in the Czech population.

    Science.gov (United States)

    Bienertova-Vasku, Julie; Bienert, Petr; Tomandl, Josef; Forejt, Martin; Vavrina, Martin; Kudelkova, Jana; Vasku, Anna

    2008-02-01

    Previously, it has been reported that mutations in the genes encoding for adipokines may be associated with impaired food intake and may serve as potential obesity biomarkers. The aim of this study was to investigate the possible associations of defined variability in leptin, leptin receptor, adiponectin, proopiomelanocortin and ghrelin genes with food preferences in the obese and non-obese Czech population and evaluate their potential as the obesity susceptibility genes. Using PCR followed by restriction analysis, we studied 185 volunteers. Basic anthropometrical characteristics associated to obesity were measured and the food intake was monitored using a 7-day record method. In the group of obese individuals, a subset of 34 morbidly obese patients was studied for plasma leptin and soluble leptin receptor levels. None of the examined polymorphisms was associated to anthropometrical or demographic characteristics of the study subjects. The Gln223Arg polymorphism within the leptin receptor gene was significantly associated with lower plasma leptin levels (the RR genotype being more frequent in patients with lower plasma leptin levels; P = 0.001). No associations of the examined polymorphisms with food preferences was observed. Based on our results, the examined polymorphisms in the adipokine genes do not seem to be the major risk factor for obesity development in the Czech population nor significantly affect food preferences.

  2. Reduction in diabetic amputations over 11 years in a defined U.K. population: benefits of multidisciplinary team work and continuous prospective audit.

    Science.gov (United States)

    Krishnan, Singhan; Nash, Fiona; Baker, Neil; Fowler, Duncan; Rayman, Gerry

    2008-01-01

    To assess changes in diabetic lower-extremity amputation rates in a defined relatively static population over an 11-year period following the introduction of a multidisciplinary foot team. All diabetic patients with foot problems admitted to Ipswich Hospital, a large district general hospital, were identified by twice-weekly surveillance of all relevant in-patient areas and outcomes including amputations recorded. The incidence of major amputations fell 62%, from 7.4 to 2.8 per 100,000 of the general population. Total amputation rates also decreased (40.3%) but to a lesser extent due to a small increase in minor amputations. Expressed as incidence per 10,000 people with diabetes, total amputations fell 70%, from 53.2 to 16.0, and major amputations fell 82%, from 36.4 to 6.7. Significant reductions in total and major amputation rates occurred over the 11-year period following improvements in foot care services including multidisciplinary team work.

  3. Norepinephrine stimulates progesterone production in highly estrogenic bovine granulosa cells cultured under serum-free, chemically defined conditions

    Directory of Open Access Journals (Sweden)

    Piccinato Carla A

    2012-11-01

    Full Text Available Abstract Background Since noradrenergic innervation was described in the ovarian follicle, the actions of the intraovarian catecholaminergic system have been the focus of a variety of studies. We aimed to determine the gonadotropin-independent effects of the catecholamine norepinephrine (NE in the steroid hormone profile of a serum-free granulosa cell (GC culture system in the context of follicular development and dominance. Methods Primary bovine GCs were cultivated in a serum-free, chemically defined culture system supplemented with 0.1% polyvinyl alcohol. The culture features were assessed by hormone measurements and ultrastructural characteristics of GCs. Results GCs produced increasing amounts of estradiol and pregnenolone for 144h and maintained ultrastructural features of healthy steroidogenic cells. Progesterone production was also detected, although it significantly increased only after 96h of culture. There was a highly significant positive correlation between estradiol and pregnenolone production in high E2-producing cultures. The effects of NE were further evaluated in a dose–response study. The highest tested concentration of NE (10 (−7 M resulted in a significant increase in progesterone production, but not in estradiol or pregnenolone production. The specificity of NE effects on progesterone productio n was further investigated by incubating GCs with propranolol (10 (−8 M, a non-selective beta-adrenergic antagonist. Conclusions The present culture system represents a robust model to study the impact of intrafollicular factors, such as catecholamines, in ovarian steroidogenesis and follicular development. The results of noradrenergic effects in the steroidogenesis of GC have implications on physiological follicular fate and on certain pathological ovarian conditions such as cyst formation and anovulation.

  4. Norepinephrine stimulates progesterone production in highly estrogenic bovine granulosa cells cultured under serum-free, chemically defined conditions.

    Science.gov (United States)

    Piccinato, Carla A; Montrezor, Luis H; Collares, Cristhianna A V; Vireque, Alessandra A; Rosa e Silva, Alzira A M

    2012-11-22

    Since noradrenergic innervation was described in the ovarian follicle, the actions of the intraovarian catecholaminergic system have been the focus of a variety of studies. We aimed to determine the gonadotropin-independent effects of the catecholamine norepinephrine (NE) in the steroid hormone profile of a serum-free granulosa cell (GC) culture system in the context of follicular development and dominance. Primary bovine GCs were cultivated in a serum-free, chemically defined culture system supplemented with 0.1% polyvinyl alcohol. The culture features were assessed by hormone measurements and ultrastructural characteristics of GCs. GCs produced increasing amounts of estradiol and pregnenolone for 144h and maintained ultrastructural features of healthy steroidogenic cells. Progesterone production was also detected, although it significantly increased only after 96h of culture. There was a highly significant positive correlation between estradiol and pregnenolone production in high E2-producing cultures. The effects of NE were further evaluated in a dose-response study. The highest tested concentration of NE (10 (-7) M) resulted in a significant increase in progesterone production, but not in estradiol or pregnenolone production. The specificity of NE effects on progesterone production was further investigated by incubating GCs with propranolol (10 (-8) M), a non-selective beta-adrenergic antagonist. The present culture system represents a robust model to study the impact of intrafollicular factors, such as catecholamines, in ovarian steroidogenesis and follicular development. The results of noradrenergic effects in the steroidogenesis of GC have implications on physiological follicular fate and on certain pathological ovarian conditions such as cyst formation and anovulation.

  5. Defining Infertility

    Science.gov (United States)

    ... Home FAQs Frequently Asked Questions Quick Facts About Infertility FAQs About Infertility FAQs About the Psychological Component of Infertility FAQs About Cloning and Stem Cell Research SART's ...

  6. Cell dualism: presence of cells with alternative membrane potentials in growing populations of bacteria and yeasts.

    Science.gov (United States)

    Ivanov, Volodymyr; Rezaeinejad, Saeid; Chu, Jian

    2013-10-01

    It is considered that all growing cells, for exception of acidophilic bacteria, have negatively charged inside cytoplasmic membrane (Δψ⁻-cells). Here we show that growing populations of microbial cells contain a small portion of cells with positively charged inside cytoplasmic membrane (Δψ⁺-cells). These cells were detected after simultaneous application of the fluorescent probes for positive membrane potential (anionic dye DIBAC⁻) and membrane integrity (propidium iodide, PI). We found in exponentially growing cell populations of Escherichia coli and Saccharomyces cerevisiae that the content of live Δψ⁻-cells was 93.6 ± 1.8 % for bacteria and 90.4 ± 4.0 % for yeasts and the content of live Δψ⁺-cells was 0.9 ± 0.3 % for bacteria and 2.4 ± 0.7 % for yeasts. Hypothetically, existence of Δψ⁺-cells could be due to short-term, about 1 min for bacteria and 5 min for yeasts, change of membrane potential from negative to positive value during the cell cycle. This change has been shown by the reversions of K⁺, Na⁺, and Ca²⁺ ions fluxes across the cell membrane during synchronous yeast culture. The transformation of Δψ(⁻-cells to Δψ⁺-cells can be explained by slow influx of K⁺ ions into Δψ⁻-cell to the trigger level of K⁺ concentration ("compression of potassium spring"), which is forming "alternative" Δψ⁺-cell for a short period, following with fast efflux of K⁺ ions out of Δψ⁺-cell ("release of potassium spring") returning cell to normal Δψ⁻ state. We anticipate our results to be a starting point to reveal the biological role of cell dualism in form of Δψ⁻- and Δψ⁺- cells.

  7. Sickle cell disease in tribal populations in India.

    Science.gov (United States)

    Colah, Roshan B; Mukherjee, Malay B; Martin, Snehal; Ghosh, Kanjaksha

    2015-05-01

    The sickle gene is widespread among many tribal population groups in India with prevalence of heterozygotes varying from 1-40 per cent. Co-inheritance of the sickle gene with β-thalassaemia, HbD Punjab and glucose-6-phosphate dehydrogenase (G6PD) deficiency has also been reported. Most of the screening programmes in India now use high performance liquid chromatography (HPLC) analysis although the solubility test is also sensitive and cheap. Sickle cell disease (SCD) among tribal populations is generally milder than among non-tribal groups with fewer episodes of painful crises, infections, acute chest syndrome and need for hospitalization. This has partly been attributed to the very high prevalence of α-thalassaemia among these tribes as well as higher foetal haemoglobin levels. However, the clinical presentation is variable with many cases having a severe presentation. There is not much information available on maternal and perinatal outcome in tribal women with sickle cell disease. Newborn screening programmes for SCD have recently been initiated in Maharashtra, Gujarat, Orissa and Chattisgarh and monitoring these birth cohorts will help to understand the natural history of SCD in India. Prenatal diagnosis is acceptable by tribal families in India. The Indian Council of Medical Research and the National Rural Health Mission in different States are undertaking outreach programmes for better management and control of the disease.

  8. Biologic characteristics of the side population of human small cell lung cancer cell line H446.

    Science.gov (United States)

    Wang, Bo; Yang, Huan; Huang, Yu-Zheng; Yan, Ru-Hong; Liu, Fen-Ju; Zhang, Jun-Ning

    2010-03-01

    Recently, the theory of cancer stem cells (CSCs) has presented new targets and orientations for tumor therapy. The major difficulties in researching CSCs include their isolation and purification. The aim of this study is to identify and characterize the side population (SP) cells in small cell lung cancer (SCLC) cell line H446, which lays the foundation for the isolation and purification of CSCs. Fluorescence-activated cell sorting (FACS) was used to sort SP and non-SP (NSP) cells from H446. Both subgroups were cultivated to survey the capacity to form into suspended tumor cell spheres. Reverse transcription-polymerase chain reaction (RT-PCR) and real-time PCR were used to evaluate the expression levels of the mRNA of CD133, ABCG2, and nucleostemin in both subgroups. The capacity of proliferation and the differences in drug resistance of both subgroups and unsorted cells were tested by the MTT method. The differentiation ability of both subgroups was determined by FACS. Proliferation was determined by subcutaneous tumor formation in nude mice. The percent of Hoechst 33342 negative cells was about (5.1 +/- 0.2)% in H446 by fluorescence microscopy. The percent of SP cells was (6.3 +/- 0.1)% by flow cytometry. SP cells had a stronger capability of forming into tumor spheres than NSP cells. The mRNA expression levels of ABCG2, CD133, and nucleostemin in SP cells were 21.60 +/- 0.26, 7.10 +/- 0.14, and 1.02 +/- 0.08 folds higher than that in NSP cells (P 0.05, respectively). In vivo, SP cells showed better proliferative ability and tougher viability when treated with drugs. SP cells can differentiate into NSP cells, but NSP cells cannot differentiate into SP cells. SP cells had a greater ability to form tumors. The H446 cell line contained some SP cells with stem cell properties. CD133 and ABCG2 may be cancer stem cell markers of SCLC.

  9. Define Project

    DEFF Research Database (Denmark)

    Munk-Madsen, Andreas

    2005-01-01

    "Project" is a key concept in IS management. The word is frequently used in textbooks and standards. Yet we seldom find a precise definition of the concept. This paper discusses how to define the concept of a project. The proposed definition covers both heavily formalized projects and informally...... organized, agile projects. Based on the proposed definition popular existing definitions are discussed....

  10. "Dermatitis" defined.

    Science.gov (United States)

    Smith, Suzanne M; Nedorost, Susan T

    2010-01-01

    The term "dermatitis" can be defined narrowly or broadly, clinically or histologically. A common and costly condition, dermatitis is underresourced compared to other chronic skin conditions. The lack of a collectively understood definition of dermatitis and its subcategories could be the primary barrier. To investigate how dermatologists define the term "dermatitis" and determine if a consensus on the definition of this term and other related terms exists. A seven-question survey of dermatologists nationwide was conducted. Of respondents (n  =  122), half consider dermatitis to be any inflammation of the skin. Nearly half (47.5%) use the term interchangeably with "eczema." Virtually all (> 96%) endorse the subcategory "atopic" under the terms "dermatitis" and "eczema," but the subcategories "contact," "drug hypersensitivity," and "occupational" are more highly endorsed under the term "dermatitis" than under the term "eczema." Over half (55.7%) personally consider "dermatitis" to have a broad meaning, and even more (62.3%) believe that dermatologists as a whole define the term broadly. There is a lack of consensus among experts in defining dermatitis, eczema, and their related subcategories.

  11. Dielectrophoretic capture of low abundance cell population using thick electrodes.

    Science.gov (United States)

    Marchalot, Julien; Chateaux, Jean-François; Faivre, Magalie; Mertani, Hichem C; Ferrigno, Rosaria; Deman, Anne-Laure

    2015-09-01

    Enrichment of rare cell populations such as Circulating Tumor Cells (CTCs) is a critical step before performing analysis. This paper presents a polymeric microfluidic device with integrated thick Carbon-PolyDimethylSiloxane composite (C-PDMS) electrodes designed to carry out dielectrophoretic (DEP) trapping of low abundance biological cells. Such conductive composite material presents advantages over metallic structures. Indeed, as it combines properties of both the matrix and doping particles, C-PDMS allows the easy and fast integration of conductive microstructures using a soft-lithography approach while preserving O2 plasma bonding properties of PDMS substrate and avoiding a cumbersome alignment procedure. Here, we first performed numerical simulations to demonstrate the advantage of such thick C-PDMS electrodes over a coplanar electrode configuration. It is well established that dielectrophoretic force ([Formula: see text]) decreases quickly as the distance from the electrode surface increases resulting in coplanar configuration to a low trapping efficiency at high flow rate. Here, we showed quantitatively that by using electrodes as thick as a microchannel height, it is possible to extend the DEP force influence in the whole volume of the channel compared to coplanar electrode configuration and maintaining high trapping efficiency while increasing the throughput. This model was then used to numerically optimize a thick C-PDMS electrode configuration in terms of trapping efficiency. Then, optimized microfluidic configurations were fabricated and tested at various flow rates for the trapping of MDA-MB-231 breast cancer cell line. We reached trapping efficiencies of 97% at 20 μl/h and 78.7% at 80 μl/h, for 100 μm thick electrodes. Finally, we applied our device to the separation and localized trapping of CTCs (MDA-MB-231) from a red blood cells sample (concentration ratio of 1:10).

  12. Derivation of keratinocytes from chicken embryonic stem cells: Establishment and characterization of differentiated proliferative cell populations

    Directory of Open Access Journals (Sweden)

    Mathilde Couteaudier

    2015-03-01

    Full Text Available A common challenge in avian cell biology is the generation of differentiated cell-lines, especially in the keratinocyte lineage. Only a few avian cell-lines are available and very few of them show an interesting differentiation profile. During the last decade, mammalian embryonic stem cell-lines were shown to differentiate into almost all lineages, including keratinocytes. Although chicken embryonic stem cells had been obtained in the 1990s, few differentiation studies toward the ectodermal lineage were reported. Consequently, we explored the differentiation of chicken embryonic stem cells toward the keratinocyte lineage by using a combination of stromal induction, ascorbic acid, BMP4 and chicken serum. During the induction period, we observed a downregulation of pluripotency markers and an upregulation of epidermal markers. Three homogenous cell populations were derived, which were morphologically similar to chicken primary keratinocytes, displaying intracellular lipid droplets in almost every pavimentous cell. These cells could be serially passaged without alteration of their morphology and showed gene and protein expression profiles of epidermal markers similar to chicken primary keratinocytes. These cells represent an alternative to the isolation of chicken primary keratinocytes, being less cumbersome to handle and reducing the number of experimental animals used for the preparation of primary cells.

  13. Distinct accessory cell requirements define two types of rat T cell hybridomas specific for unique determinants in the encephalitogenic 68-86 region of myelin basic protein

    International Nuclear Information System (INIS)

    Mannie, M.D.; Paterson, P.Y.; Thomas, D.W.; Nairn, R.

    1990-01-01

    Six clonotypically unique T cell hybridomas from Lewis rats were used to study accessory cell activities required for class II MHC restricted T cell responses to the 68-86 encephalitogenic sequence of myelin basic protein (MBP). T cell hybrids which were cultured with GP68-86 68-86 sequence of guinea pig MBP (GPMBP) and naive splenocytes (SPL) were induced to produce IL-2 as measured by the CTLL indicator cell line. The hybrids were categorized into two subsets (designated THYB-1 and THYB-2), because two distinct subset-specific pathways of communication between accessory cells and T cells were involved in GPMBP-induced IL-2 production. These pathways were distinguished by the following six observations. First, when the duration of a pulse of SPL with GPMBP was lengthened from 1 to 4 h, these SPL lost their ability to induce IL-2 production by THYB-2 hybrids yet nevertheless retained full stimulatory activity for THYB-1 hybrids. Second, paraformaldehyde fixation of GPMBP-pulsed SPL abrogated an activity necessary for Ag-induced IL-2 production by THYB-2 hybrids. These fixed SPL were nevertheless able to stimulate THYB-1 hybrids, albeit to a lesser extent than viable unfixed SPL. Third, the addition of either cycloheximide, cytochalasin B, or 2-deoxyglucose to an Ag pulse of SPL with GPMBP dramatically inhibited the subsequent responses of THYB-2 hybrids yet had little or no effect upon the reactivity of THYB-1 hybrids. Fourth, thymocytes lacked necessary activities for GPMBP evoked IL-2 production by THYB-2 hybrids yet strongly promoted THYB-1 hybrid responses. Fifth, exposure of SPL to as little as 500 rad of gamma-irradiation markedly attenuated THYB-2 hybrid response to GPMBP but did not affect THYB-1 responses. Sixth, anti-GPMBP responses by THYB-2 hybrids were observed only in the presence of both radioresistant adherent SPL and a distinct population of radiosensitive nonadherent SPL

  14. Comparison of tumor biology of two distinct cell sub-populations in lung cancer stem cells.

    Science.gov (United States)

    Wang, Jianyu; Sun, Zhiwei; Liu, Yongli; Kong, Liangsheng; Zhou, Shixia; Tang, Junlin; Xing, Hongmei Rosie

    2017-11-14

    Characterization of the stem-like properties of cancer stem cells (CSCs) remain indirect and qualitative, especially the ability of CSCs to undergo asymmetric cell division for self renewal and differentiation, a unique property of cells of stem origin. It is partly due to the lack of stable cellular models of CSCs. In this study, we developed a new approach for CSC isolation and purification to derive a CSC-enriched cell line (LLC-SE). By conducting five consecutive rounds of single cell cloning using the LLC-SE cell line, we obtained two distinct sub-population of cells within the Lewis lung cancer CSCs that employed largely symmetric division for self-renewal (LLC-SD) or underwent asymmetric division for differentiation (LLC-ASD). LLC-SD and LLC-ASD cell lines could be stably passaged in culture and be distinguished by cell morphology, stem cell marker, spheroid formation and subcutaneous tumor initiation efficiency, as well as orthotopic lung tumor growth, progression and survival. The ability LLC-ASD cells to undergo asymmetric division was visualized and quantified by the asymmetric segregation of labeled BrdU and NUMB to one of the two daughter cells in anaphase cell division. The more stem-like LLC-SD cells exhibited higher capacity for tumorigenesis and progression and shorter survival. As few as 10 LLC-SD could initiate subcutaneous tumor growth when transplanted to the athymic mice. Collectively, these observations suggest that the SD-type of cells appear to be on the top of the hierarchical order of the CSCs. Furthermore, they have lead to generated cellular models of CSC self-renewal for future mechanistic investigations.

  15. Clonal cell populations unresponsive to radiosensitization induced by telomerase inhibition

    International Nuclear Information System (INIS)

    Ju, Yeun-Jin; Shin, Hyun-Jin; Park, Jeong-Eun; Juhn, Kyoung-Mi; Woo, Seon Rang; Kim, Hee-Young; Han, Young-Hoon; Hwang, Sang-Gu; Hong, Sung-Hee; Kang, Chang-Mo; Yoo, Young-Do; Park, Won-Bong; Cho, Myung-Haing; Park, Gil Hong; Lee, Kee-Ho

    2010-01-01

    Research highlights: → In our present manuscript, we have clearly showed an interesting but problematic obstacle of a radiosensitization strategy based on telomerase inhibition by showing that: Clonal population unresponsive to this radiosensitization occasionally arise. → The telomere length of unsensitized clones was reduced, as was that of most sensitized clones. → The unsensitized clones did not show chromosome end fusion which was noted in all sensitized clones. → P53 status is not associated with the occurrence of unsensitized clone. → Telomere end capping in unsensitized clone is operative even under telomerase deficiency. -- Abstract: A combination of a radiotherapeutic regimen with telomerase inhibition is valuable when tumor cells are to be sensitized to radiation. Here, we describe cell clones unresponsive to radiosensitization after telomere shortening. After extensive division of individual transformed clones of mTERC -/- cells, about 22% of clones were unresponsive to radiosensitization even though telomerase action was inhibited. The telomere lengths of unsensitized mTERC -/- clones were reduced, as were those of most sensitized clones. However, the unsensitized clones did not exhibit chromosomal end-to-end fusion to the extent noted in all sensitized clones. Thus, a defense mechanism preventing telomere erosion is operative even when telomeres become shorter under conditions of telomerase deficiency, and results in unresponsiveness to the radiosensitization generally mediated by telomere shortening.

  16. Increasing cell culture population doublings for long-term growth of finite life span human cell cultures

    Science.gov (United States)

    Stampfer, Martha R; Garbe, James C

    2015-02-24

    Cell culture media formulations for culturing human epithelial cells are herein described. Also described are methods of increasing population doublings in a cell culture of finite life span human epithelial cells and prolonging the life span of human cell cultures. Using the cell culture media disclosed alone and in combination with addition to the cell culture of a compound associated with anti-stress activity achieves extended growth of pre-stasis cells and increased population doublings and life span in human epithelial cell cultures.

  17. Associations between Physical Activity and Obesity Defined by Waist-To-Height Ratio and Body Mass Index in the Korean Population.

    Science.gov (United States)

    Lee, On; Lee, Duck-Chul; Lee, Sukho; Kim, Yeon Soo

    2016-01-01

    This study investigated the associations between physical activity and the prevalence of obesity determined by waist-to-height ratio (WHtR) and body mass index (BMI). This is the first study to our knowledge on physical activity and obesity using a nationally representative sample of South Korean population from The Korea National Health and Nutrition Examination Survey. We categorized individuals into either non-obese or obese defined by WHtR and BMI. Levels of moderate-to-vigorous physical activity were classified as 'Inactive', 'Active', and 'Very active' groups based on the World Health Organization physical activity guidelines. Multivariable logistic regression was used to examine the associations between physical activity and the prevalence of obesity. Physical activity was significantly associated with a lower prevalence of obesity using both WHtR and BMI. Compared to inactive men, odds ratios (ORs) (95% confidence intervals [CIs]) for obesity by WHtR ≥0.50 were 0.69 (0.53-0.89) in active men and 0.76 (0.63-0.91) in very active men (p for trend = 0.007). The ORs (95% CIs) for obesity by BMI ≥25 kg/m2 were 0.78 (0.59-1.03) in active men and 0.82 (0.67-0.99) in very active men (p for trend = 0.060). The ORs (95% CIs) for obesity by BMI ≥30 kg/m2 were 0.40 (0.15-0.98) in active men and 0.90 (0.52-1.56) in very active men (p for trend = 0.978). Compared to inactive women, the ORs (95% CIs) for obesity by WHtR ≥0.50 were 0.94 (0.75-1.18) in active women and 0.84 (0.71-0.998) in very active women (p for trend = 0.046). However, no significant associations were found between physical activity and obesity by BMI in women. We found more significant associations between physical activity and obesity defined by WHtR than BMI. However, intervention studies are warranted to investigate and compare causal associations between physical activity and different obesity measures in various populations.

  18. Yeast cells contain a heterogeneous population of peroxisomes that segregate asymmetrically during cell division

    NARCIS (Netherlands)

    Kumar, Sanjeev; de Boer, Rinse; van der Klei, Ida J

    2018-01-01

    Here we used fluorescence microscopy and a peroxisome-targeted tandem fluorescent protein timer to determine the relative age of peroxisomes in yeast. Our data indicate that yeast cells contain a heterogeneous population of relatively old and younger peroxisomes. During budding the peroxisome

  19. Characterization of distinct mesenchymal-like cell populations from human skeletal muscle in situ and in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Lecourt, Severine, E-mail: severine.lecourt@sls.aphp.fr [UPMC/AIM UMR S 974, Groupe Hospitalier Pitie-Salpetriere, Paris (France); INSERM U974, Groupe Hospitalier Pitie-Salpetriere, Paris (France); CNRS UMR 7215, Groupe Hospitalier Pitie-Salpetriere, Paris (France); Laboratoire de Therapie Cellulaire, Hopital Saint Louis, Paris (France); Marolleau, Jean-Pierre, E-mail: Marolleau.Jean-Pierre@chu-amiens.fr [Laboratoire de Therapie Cellulaire, Hopital Saint Louis, Paris (France); CHU Amiens Hopital Sud, Service d' Hematologie Clinique, UPJV, Amiens (France); Fromigue, Olivia, E-mail: olivia.fromigue@larib.inserm.fr [INSERM U606, Universite Paris 07, Hopital Lariboisiere, Paris (France); Vauchez, Karine, E-mail: k.vauchez@institut-myologie.org [UPMC/AIM UMR S 974, Groupe Hospitalier Pitie-Salpetriere, Paris (France); INSERM U974, Groupe Hospitalier Pitie-Salpetriere, Paris (France); CNRS UMR 7215, Groupe Hospitalier Pitie-Salpetriere, Paris (France); Genzyme S.A.S., Saint-Germain en Laye (France); Andriamanalijaona, Rina, E-mail: rinandria@yahoo.fr [Laboratoire de Biochimie des Tissus Conjonctifs, Faculte de Medecine, Caen (France); Ternaux, Brigitte, E-mail: brigitte.ternaux@orange.fr [Laboratoire de Therapie Cellulaire, Hopital Saint Louis, Paris (France); Lacassagne, Marie-Noelle, E-mail: mnlacassagne@free.fr [Laboratoire de Therapie Cellulaire, Hopital Saint Louis, Paris (France); Robert, Isabelle, E-mail: isa-robert@hotmail.fr [Laboratoire de Therapie Cellulaire, Hopital Saint Louis, Paris (France); Boumediene, Karim, E-mail: karim.boumediene@unicaen.fr [Laboratoire de Biochimie des Tissus Conjonctifs, Faculte de Medecine, Caen (France); Chereau, Frederic, E-mail: fchereau@pervasistx.com [Myosix S.A., Saint-Germain en Laye (France); Marie, Pierre, E-mail: pierre.marie@larib.inserm.fr [INSERM U606, Universite Paris 07, Hopital Lariboisiere, Paris (France); and others

    2010-09-10

    Human skeletal muscle is an essential source of various cellular progenitors with potential therapeutic perspectives. We first used extracellular markers to identify in situ the main cell types located in a satellite position or in the endomysium of the skeletal muscle. Immunohistology revealed labeling of cells by markers of mesenchymal (CD13, CD29, CD44, CD47, CD49, CD62, CD73, CD90, CD105, CD146, and CD15 in this study), myogenic (CD56), angiogenic (CD31, CD34, CD106, CD146), hematopoietic (CD10, CD15, CD34) lineages. We then analysed cell phenotypes and fates in short- and long-term cultures of dissociated muscle biopsies in a proliferation medium favouring the expansion of myogenic cells. While CD56{sup +} cells grew rapidly, a population of CD15{sup +} cells emerged, partly from CD56{sup +} cells, and became individualized. Both populations expressed mesenchymal markers similar to that harboured by human bone marrow-derived mesenchymal stem cells. In differentiation media, both CD56{sup +} and CD15{sup +} cells shared osteogenic and chondrogenic abilities, while CD56{sup +} cells presented a myogenic capacity and CD15{sup +} cells presented an adipogenic capacity. An important proportion of cells expressed the CD34 antigen in situ and immediately after muscle dissociation. However, CD34 antigen did not persist in culture and this initial population gave rise to adipogenic cells. These results underline the diversity of human muscle cells, and the shared or restricted commitment abilities of the main lineages under defined conditions.

  20. A millifluidic study of cell-to-cell heterogeneity in growth-rate and cell-division capability in populations of isogenic cells of Chlamydomonas reinhardtii.

    Directory of Open Access Journals (Sweden)

    Shima P Damodaran

    Full Text Available To address possible cell-to-cell heterogeneity in growth dynamics of isogenic cell populations of Chlamydomonas reinhardtii, we developed a millifluidic drop-based device that not only allows the analysis of populations grown from single cells over periods of a week, but is also able to sort and collect drops of interest, containing viable and healthy cells, which can be used for further experimentation. In this study, we used isogenic algal cells that were first synchronized in mixotrophic growth conditions. We show that these synchronized cells, when placed in droplets and kept in mixotrophic growth conditions, exhibit mostly homogeneous growth statistics, but with two distinct subpopulations: a major population with a short doubling-time (fast-growers and a significant subpopulation of slowly dividing cells (slow-growers. These observations suggest that algal cells from an isogenic population may be present in either of two states, a state of restricted division and a state of active division. When isogenic cells were allowed to propagate for about 1000 generations on solid agar plates, they displayed an increased heterogeneity in their growth dynamics. Although we could still identify the original populations of slow- and fast-growers, drops inoculated with a single progenitor cell now displayed a wider diversity of doubling-times. Moreover, populations dividing with the same growth-rate often reached different cell numbers in stationary phase, suggesting that the progenitor cells differed in the number of cell divisions they could undertake. We discuss possible explanations for these cell-to-cell heterogeneities in growth dynamics, such as mutations, differential aging or stochastic variations in metabolites and macromolecules yielding molecular switches, in the light of single-cell heterogeneities that have been reported among isogenic populations of other eu- and prokaryotes.

  1. Morphometric Evaluation of Occipital Condyles: Defining Optimal Trajectories and Safe Screw Lengths for Occipital Condyle-Based Occipitocervical Fixation in Indian Population.

    Science.gov (United States)

    Bosco, Aju; Venugopal, Prakash; Shetty, Ajoy Prasad; Shanmuganathan, Rajasekaran; Kanna, Rishi Mugesh

    2018-04-01

    Computed tomographic (CT) morphometric analysis. To assess the feasibility and safety of occipital condyle (OC)-based occipitocervical fixation (OCF) in Indians and to define anatomical zones and screw lengths for safe screw placement. Limitations of occipital squama-based OCF has led to development of two novel OC-based OCF techniques. Morphometric analysis was performed on the OCs of 70 Indian adults. The feasibility of placing a 3.5-mm-diameter screw into OCs was investigated. Safe trajectories and screw lengths for OC screws and C0-C1 transarticular screws without hypoglossal canal or atlantooccipital joint compromise were estimated. The average screw length and safe sagittal and medial angulations for OC screws were 19.9±2.3 mm, ≤6.4°±2.4° cranially, and 31.1°±3° medially, respectively. An OC screw could not be accommodated by 27% of the population. The safe sagittal angles and screw lengths for C0-C1 transarticular screw insertion (48.9°±5.7° cranial, 26.7±2.9 mm for junctional entry technique; 36.7°±4.6° cranial, 31.6±2.7 mm for caudal C1 arch entry technique, respectively) were significantly different than those in other populations. The risk of vertebral artery injury was high for the caudal C1 arch entry technique. Screw placement was uncertain in 48% of Indians due to the presence of aberrant anatomy. There were significant differences in the metrics of OC-based OCF between Indian and other populations. Because of the smaller occipital squama dimensions in Indians, OC-based OCF techniques may have a higher application rate and could be a viable alternative/salvage option in selected cases. Preoperative CT, including three-dimensional-CT-angiography (to delineate vertebral artery course), is imperative to avoid complications resulting from aberrant bony and vascular anatomy. Our data can serve as a valuable reference guide in placing these screws safely under fluoroscopic guidance.

  2. Characterisation of innate lymphoid cell populations at different sites in mice with defective T cell immunity [version 3; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Emma E. Dutton

    2018-03-01

    Full Text Available Background: Innate lymphoid cells (ILCs have now been identified within most tissues of the body and current evidence indicates that this family of cells play a fundamental role in maintaining tissue homeostasis. However, few studies have compared the ILC populations between several tissues. Methods: We sought to generate a comprehensive characterisation of the ILC populations in different tissues of C57BL/6 WT and genetically modified mice targeting costimulatory pathways, using transcription factor expression to define specific groups. Results: Consistent with studies individually describing the ILC composition in different tissues, our analysis revealed different ILC groups dominate the ILC population in different tissues. Additionally, we observed a population of  IL-7Rα+Id2+ cells lacking expression of lineage markers but also lacking expression of GATA-3, RORgt or T-bet. This population was most evident in ear skin where it outnumbered the defined ILC groups, however, further experiments demonstrated that detection of these cells was influenced by how the tissue was digested, raising concerns as to its real nature. Since both ILC2 and ILC3 express ICOS, we then investigated the requirement for ICOS:ICOSL interactions in the homeostasis of ILC populations at these sites. Surprisingly, no significant differences were detected in the number of ILC1, ILC2 or ILC3 between WT and ICOSL-/- mice in any tissue, indicating that this pathway is not required for ILC homeostasis at these sites. These data were compared with CD80-/-CD86-/- mice given evidence of CD28 expression by some ILC and ILC crosstalk with activated T cells. Notably, the absence of CD28 ligands resulted in a significant increase in ILC2 and ILC3 numbers in the intestine. Conclusions: Together, these data provide new insight into ILC composition in different tissues in both WT and genetically modified mice where key costimulatory pathways are genetically deleted, providing a

  3. Use of Multicolor Flow Cytometry for Isolation of Specific Cell Populations Deriving from Differentiated Human Embryonic Stem Cells

    NARCIS (Netherlands)

    Mengarelli, Isabella; Fryga, Andrew; Barberi, Tiziano

    2016-01-01

    Flow Cytometry-Sorting (FCM-Sorting) is a technique commonly used to identify and isolate specific types of cells from a heterogeneous population of live cells. Here we describe a multicolor flow cytometry technique that uses five distinct cell surface antigens to isolate four live populations with

  4. Defining chaos.

    Science.gov (United States)

    Hunt, Brian R; Ott, Edward

    2015-09-01

    In this paper, we propose, discuss, and illustrate a computationally feasible definition of chaos which can be applied very generally to situations that are commonly encountered, including attractors, repellers, and non-periodically forced systems. This definition is based on an entropy-like quantity, which we call "expansion entropy," and we define chaos as occurring when this quantity is positive. We relate and compare expansion entropy to the well-known concept of topological entropy to which it is equivalent under appropriate conditions. We also present example illustrations, discuss computational implementations, and point out issues arising from attempts at giving definitions of chaos that are not entropy-based.

  5. A population dynamics analysis of the interaction between adaptive regulatory T cells and antigen presenting cells.

    Directory of Open Access Journals (Sweden)

    David Fouchet

    Full Text Available BACKGROUND: Regulatory T cells are central actors in the maintenance of tolerance of self-antigens or allergens and in the regulation of the intensity of the immune response during infections by pathogens. An understanding of the network of the interaction between regulatory T cells, antigen presenting cells and effector T cells is starting to emerge. Dynamical systems analysis can help to understand the dynamical properties of an interaction network and can shed light on the different tasks that can be accomplished by a network. METHODOLOGY AND PRINCIPAL FINDINGS: We used a mathematical model to describe a interaction network of adaptive regulatory T cells, in which mature precursor T cells may differentiate into either adaptive regulatory T cells or effector T cells, depending on the activation state of the cell by which the antigen was presented. Using an equilibrium analysis of the mathematical model we show that, for some parameters, the network has two stable equilibrium states: one in which effector T cells are strongly regulated by regulatory T cells and another in which effector T cells are not regulated because the regulatory T cell population is vanishingly small. We then simulate different types of perturbations, such as the introduction of an antigen into a virgin system, and look at the state into which the system falls. We find that whether or not the interaction network switches from the regulated (tolerant state to the unregulated state depends on the strength of the antigenic stimulus and the state from which the network has been perturbed. CONCLUSION/SIGNIFICANCE: Our findings suggest that the interaction network studied in this paper plays an essential part in generating and maintaining tolerance against allergens and self-antigens.

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

    Science.gov (United States)

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

    2016-01-01

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

  7. Defining Cyberbullying.

    Science.gov (United States)

    Englander, Elizabeth; Donnerstein, Edward; Kowalski, Robin; Lin, Carolyn A; Parti, Katalin

    2017-11-01

    Is cyberbullying essentially the same as bullying, or is it a qualitatively different activity? The lack of a consensual, nuanced definition has limited the field's ability to examine these issues. Evidence suggests that being a perpetrator of one is related to being a perpetrator of the other; furthermore, strong relationships can also be noted between being a victim of either type of attack. It also seems that both types of social cruelty have a psychological impact, although the effects of being cyberbullied may be worse than those of being bullied in a traditional sense (evidence here is by no means definitive). A complicating factor is that the 3 characteristics that define bullying (intent, repetition, and power imbalance) do not always translate well into digital behaviors. Qualities specific to digital environments often render cyberbullying and bullying different in circumstances, motivations, and outcomes. To make significant progress in addressing cyberbullying, certain key research questions need to be addressed. These are as follows: How can we define, distinguish between, and understand the nature of cyberbullying and other forms of digital conflict and cruelty, including online harassment and sexual harassment? Once we have a functional taxonomy of the different types of digital cruelty, what are the short- and long-term effects of exposure to or participation in these social behaviors? What are the idiosyncratic characteristics of digital communication that users can be taught? Finally, how can we apply this information to develop and evaluate effective prevention programs? Copyright © 2017 by the American Academy of Pediatrics.

  8. Immunotherapy of non-Hodgkin lymphoma with a defined ratio of CD8+ and CD4+ CD19-specific chimeric antigen receptor-modified T cells

    Science.gov (United States)

    Turtle, Cameron J.; Hanafi, Laïla-Aïcha; Berger, Carolina; Hudecek, Michael; Pender, Barbara; Robinson, Emily; Hawkins, Reed; Chaney, Colette; Cherian, Sindhu; Chen, Xueyan; Soma, Lorinda; Wood, Brent; Li, Daniel; Heimfeld, Shelly; Riddell, Stanley R.; Maloney, David G.

    2016-01-01

    CD19-specific chimeric antigen receptor (CAR)-modified T cells have antitumor activity in B cell malignancies, but factors that impact toxicity and efficacy have been difficult to define because of differences in lymphodepletion regimens and heterogeneity of CAR-T cells administered to individual patients. We conducted a clinical trial in which CD19 CAR-T cells were manufactured from defined T cell subsets and administered in a 1:1 CD4+:CD8+ ratio of CAR-T cells to 32 adults with relapsed and/or refractory B cell non-Hodgkin lymphoma after cyclophosphamide (Cy)-based lymphodepletion chemotherapy with or without fludarabine (Flu). Patients who received Cy/Flu lymphodepletion had markedly increased CAR-T cell expansion and persistence, and higher response rates (50% CR, 72% ORR, n=20) than patients who received Cy-based lymphodepletion without Flu (8% CR, 50% ORR, n=12). The complete response (CR) rate in patients treated with Cy/Flu at the maximally tolerated dose was 64% (82% ORR, n=11). Cy/Flu minimized the effects of an immune response to the murine scFv component of the CAR, which limited CAR-T cell expansion, persistence, and clinical efficacy in patients who received Cy-based lymphodepletion without Flu. Severe cytokine release syndrome (sCRS) and grade ≥ 3 neurotoxicity were observed in 13% and 28% of all patients, respectively. Serum biomarkers one day after CAR-T cell infusion correlated with subsequent development of sCRS and neurotoxicity. Immunotherapy with CD19 CAR-T cells in a defined CD4+:CD8+ ratio allowed identification of correlative factors for CAR-T cell expansion, persistence, and toxicity, and facilitated optimization of a lymphodepletion regimen that improved disease response and overall and progression-free survival. PMID:27605551

  9. Monolayer culturing and cloning of human pluripotent stem cells on laminin-521-based matrices under xeno-free and chemically defined conditions.

    Science.gov (United States)

    Rodin, Sergey; Antonsson, Liselotte; Hovatta, Outi; Tryggvason, Karl

    2014-10-01

    A robust method for culturing human pluripotent stem (hPS) cells under chemically defined and xeno-free conditions is an important tool for stem cell research and for the development of regenerative medicine. Here, we describe a protocol for monolayer culturing of Oct-4-positive hPS cells on a specific laminin-521 (LN-521) isoform, under xeno-free and chemically defined conditions. The cells are dispersed into single-cell suspension and then plated on LN-521 isoform at densities higher than 5,000 cells per cm², where they attach, migrate and survive by forming small monolayer cell groups. The cells avidly divide and expand horizontally until the entire dish is covered by a confluent monolayer. LN-521, in combination with E-cadherin, allows cloning of individual hPS cells in separate wells of 96-well plates without the presence of rho-associated protein kinase (ROCK) inhibitors or any other inhibitors of anoikis. Characterization of cells maintained for several months in culture reveals pluripotency with a minimal degree of genetic abnormalities.

  10. T Cell Epitope Immunotherapy Induces a CD4+ T Cell Population with Regulatory Activity

    Directory of Open Access Journals (Sweden)

    Verhoef Adrienne

    2005-01-01

    Full Text Available Background Synthetic peptides, representing CD4+ T cell epitopes, derived from the primary sequence of allergen molecules have been used to down-regulate allergic inflammation in sensitised individuals. Treatment of allergic diseases with peptides may offer substantial advantages over treatment with native allergen molecules because of the reduced potential for cross-linking IgE bound to the surface of mast cells and basophils. Methods and Findings In this study we address the mechanism of action of peptide immunotherapy (PIT in cat-allergic, asthmatic patients. Cell-division-tracking dyes, cell-mixing experiments, surface phenotyping, and cytokine measurements were used to investigate immunomodulation in peripheral blood mononuclear cells (PBMCs after therapy. Proliferative responses of PBMCs to allergen extract were significantly reduced after PIT. This was associated with modified cytokine profiles generally characterised by an increase in interleukin-10 and a decrease in interleukin-5 production. CD4+ cells isolated after PIT were able to actively suppress allergen-specific proliferative responses of pretreatment CD4neg PBMCs in co-culture experiments. PIT was associated with a significant increase in surface expression of CD5 on both CD4+ and CD8+ PBMCs. Conclusion This study provides evidence for the induction of a population of CD4+ T cells with suppressor/regulatory activity following PIT. Furthermore, up-regulation of cell surface levels of CD5 may contribute to reduced reactivity to allergen.

  11. Programming strategy for efficient modeling of dynamics in a population of heterogeneous cells

    DEFF Research Database (Denmark)

    Hald, Bjørn Olav; Hendriksen, Morten; Sørensen, Preben Graae

    2013-01-01

    Heterogeneity is a ubiquitous property of biological systems. Even in a genetically identical population of a single cell type, cell-to-cell differences are observed. Although the functional behavior of a given population is generally robust, the consequences of heterogeneity are fairly unpredict...

  12. The CEA−/lo colorectal cancer cell population harbors cancer stem cells and metastatic cells

    Science.gov (United States)

    Zhang, Bo; Mu, Lei; Huang, Kaiyu; Zhao, Hui; Ma, Chensen; Li, Xiaolan; Tao, Deding; Gong, Jianping; Qin, Jichao

    2016-01-01

    Serum carcinoembryonic antigen (CEA) is the most commonly used tumor marker in a variety of cancers including colorectal cancer (CRC) for tumor diagnosis and monitoring. Recent studies have shown that colonic crypt cells expressing little or no CEA may enrich for stem cells. Numerous studies have clearly shown that there exist CRC patients with normal serum CEA levels during tumor progression or even tumor relapse, although CEA itself is considered to promote metastasis and block cell differentiation. These seemingly contradictory observations prompted us to investigate, herein, the biological properties as well as tumorigenic and metastatic capacity of CRC cells that express high (CEA+) versus low CEA (CEA−/lo) levels of CEA. Our findings show that the abundance of CEA−/lo cells correlate with poor differentiation and poor prognosis, and moreover, CEA−/lo cells form more spheres in vitro, generate more tumors and exhibit a higher potential in developing liver and lung metastases than corresponding CEA+ cells. Applying RNAi-mediated approach, we found that IGF1R mediated tumorigenic and capacity of CEA−/lo cells but did not mediate those of CEA+ cells. Notably, our data demonstrated that CEA molecule was capable of protecting CEA−/lo cells from anoikis, implying that CEA+ cells, although themselves possessing less tumorigenic and metastatic capacity, may promote metastasis of CEA−/lo cells via secreting CEA molecule. Our observations suggest that, besides targeting CEA molecule, CEA−/lo cells may represent a critical source of tumor progression and metastasis, and should therefore be the target of future therapies. PMID:27813496

  13. Conserved features of cancer cells define their sensitivity to HAMLET-induced death; c-Myc and glycolysis.

    Science.gov (United States)

    Storm, P; Aits, S; Puthia, M K; Urbano, A; Northen, T; Powers, S; Bowen, B; Chao, Y; Reindl, W; Lee, D Y; Sullivan, N L; Zhang, J; Trulsson, M; Yang, H; Watson, J D; Svanborg, C

    2011-12-01

    HAMLET is the first member of a new family of tumoricidal protein-lipid complexes that kill cancer cells broadly, while sparing healthy, differentiated cells. Many and diverse tumor cell types are sensitive to the lethal effect, suggesting that HAMLET identifies and activates conserved death pathways in cancer cells. Here, we investigated the molecular basis for the difference in sensitivity between cancer cells and healthy cells. Using a combination of small-hairpin RNA (shRNA) inhibition, proteomic and metabolomic technology, we identified the c-Myc oncogene as one essential determinant of HAMLET sensitivity. Increased c-Myc expression levels promoted sensitivity to HAMLET and shRNA knockdown of c-Myc suppressed the lethal response, suggesting that oncogenic transformation with c-Myc creates a HAMLET-sensitive phenotype. Furthermore, HAMLET sensitivity was modified by the glycolytic state of tumor cells. Glucose deprivation sensitized tumor cells to HAMLET-induced cell death and in the shRNA screen, hexokinase 1 (HK1), 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 1 and hypoxia-inducible factor 1α modified HAMLET sensitivity. HK1 was shown to bind HAMLET in a protein array containing ∼8000 targets, and HK activity decreased within 15 min of HAMLET treatment, before morphological signs of tumor cell death. In parallel, HAMLET triggered rapid metabolic paralysis in carcinoma cells. Tumor cells were also shown to contain large amounts of oleic acid and its derivatives already after 15 min. The results identify HAMLET as a novel anti-cancer agent that kills tumor cells by exploiting unifying features of cancer cells such as oncogene addiction or the Warburg effect.

  14. Conserved features of cancer cells define their sensitivity of HAMLET-induced death; c-Myc and glycolysis

    Science.gov (United States)

    Storm, Petter; Puthia, Manoj Kumar; Aits, Sonja; Urbano, Alexander; Northen, Trent; Powers, Scott; Bowen, Ben; Chao, Yinxia; Reindl, Wolfgang; Lee, Do Yup; Sullivan, Nancy Liu; Zhang, Jianping; Trulsson, Maria; Yang, Henry; Watson, James; Svanborg, Catharina

    2014-01-01

    HAMLET is the first member of a new family of tumoricidal protein-lipid complexes that kill cancer cells broadly, while sparing healthy, differentiated cells. Many and diverse tumor cell types are sensitive to the lethal effect, suggesting that HAMLET identifies and activates conserved death pathways in cancer cells. Here we investigated the molecular basis for the difference in sensitivity between cancer cells and healthy cells. Using a combination of small hairpin RNA inhibition, proteomic and metabolomic technology we identified the c-Myc oncogene as one essential determinant of HAMLET sensitivity. Increased c-Myc expression levels promoted the sensitivity to HAMLET and shRNA knockdown of c-Myc suppressed the lethal response, suggesting that oncogenic transformation with c-Myc creates a HAMLET-sensitive phenotype. Furthermore, the HAMLET sensitivity was modified by the glycolytic state of the tumor cells. Glucose deprivation sensitized tumor cells to HAMLET-induced cell death and in the shRNA screen Hexokinase 1, PFKFB1 and HIF1α modified HAMLET sensitivity. Hexokinase 1 was shown to bind HAMLET in a protein array containing approximately 8000 targets and Hexokinase activity decreased within 15 minutes of HAMLET treatment, prior to morphological signs of tumor cell death. In parallel, HAMLET triggered rapid metabolic paralysis in carcinoma cells. The glycolytic machinery was modified and glycolysis was shifted towards the pentose phosphate pathway. Tumor cells were also shown to contain large amounts of oleic acid and its derivatives already after 15 minutes. The results identify HAMLET as a novel anti-cancer agent that kills tumor cells by exploiting unifying features of cancer cells such as oncogene-addiction or the Warburg effect. PMID:21643007

  15. Making sense of snapshot data: ergodic principle for clonal cell populations.

    Science.gov (United States)

    Thomas, Philipp

    2017-11-01

    Population growth is often ignored when quantifying gene expression levels across clonal cell populations. We develop a framework for obtaining the molecule number distributions in an exponentially growing cell population taking into account its age structure. In the presence of generation time variability, the average acquired across a population snapshot does not obey the average of a dividing cell over time, apparently contradicting ergodicity between single cells and the population. Instead, we show that the variation observed across snapshots with known cell age is captured by cell histories, a single-cell measure obtained from tracking an arbitrary cell of the population back to the ancestor from which it originated. The correspondence between cells of known age in a population with their histories represents an ergodic principle that provides a new interpretation of population snapshot data. We illustrate the principle using analytical solutions of stochastic gene expression models in cell populations with arbitrary generation time distributions. We further elucidate that the principle breaks down for biochemical reactions that are under selection, such as the expression of genes conveying antibiotic resistance, which gives rise to an experimental criterion with which to probe selection on gene expression fluctuations. © 2017 The Author(s).

  16. Phenotypic switching of populations of cells in a stochastic environment

    Science.gov (United States)

    Hufton, Peter G.; Lin, Yen Ting; Galla, Tobias

    2018-02-01

    In biology phenotypic switching is a common bet-hedging strategy in the face of uncertain environmental conditions. Existing mathematical models often focus on periodically changing environments to determine the optimal phenotypic response. We focus on the case in which the environment switches randomly between discrete states. Starting from an individual-based model we derive stochastic differential equations to describe the dynamics, and obtain analytical expressions for the mean instantaneous growth rates based on the theory of piecewise-deterministic Markov processes. We show that optimal phenotypic responses are non-trivial for slow and intermediate environmental processes, and systematically compare the cases of periodic and random environments. The best response to random switching is more likely to be heterogeneity than in the case of deterministic periodic environments, net growth rates tend to be higher under stochastic environmental dynamics. The combined system of environment and population of cells can be interpreted as host-pathogen interaction, in which the host tries to choose environmental switching so as to minimise growth of the pathogen, and in which the pathogen employs a phenotypic switching optimised to increase its growth rate. We discuss the existence of Nash-like mutual best-response scenarios for such host-pathogen games.

  17. Papillary neoplasia of the breast: immunohistochemically defined myoepithelial cells in the diagnosis of benign and malignant papillary breast neoplasms.

    Science.gov (United States)

    Raju, U B; Lee, M W; Zarbo, R J; Crissman, J D

    1989-11-01

    The presence or absence of myoepithelial cells (ME) has been considered as an important feature in the differential diagnosis of benign and malignant papillary lesions of the breast. We evaluated the distribution of myoepithelial cells in formalin-fixed paraffin-embedded tissue sections of 25 papillomas and 18 papillary carcinomas by ABC immunoperoxidase technique with antibodies to muscle actin (HHF-35) and high molecular weight (HMW) keratin (clone 34BE12, cytokeratins 1, 5, 10, and 14; reacting preferentially with ME cells) and an antiserum to S-100 protein. Also included in the study were eight cases of micropapillary ductal carcinoma in situ (DCIS) having a few fibrovascular cores and five peripheral papillomas with accompanying ductal carcinoma in situ or atypical hyperplasia. The antibodies to muscle actin were sensitive and relatively specific for ME cells of the breast and uniformly labeled ME cells in all 25 papillomas. ME cells were absent or extremely sparse in papillary carcinomas. They were present focally in some of the fibrovascular cores of the micropapillary DCIS, and a mixed pattern was observed in peripheral papillomas with areas of carcinoma. HMW keratin was variably expressed in ME cells in most cases with positive internal controls and was present in several normal ductal and papilloma epithelial cells but not in epithelial cells of papillary carcinomas. HMW keratin, although less specific for ME cells, was a useful adjunct because of its reactivity with ME cells as well as hyperplastic epithelial cells in papillomas, which resulted in a combined positive reaction.(ABSTRACT TRUNCATED AT 250 WORDS)

  18. Defined Essential 8™ Medium and Vitronectin Efficiently Support Scalable Xeno-Free Expansion of Human Induced Pluripotent Stem Cells in Stirred Microcarrier Culture Systems

    Science.gov (United States)

    Badenes, Sara M.; Fernandes, Tiago G.; Cordeiro, Cláudia S. M.; Boucher, Shayne; Kuninger, David; Vemuri, Mohan C.; Diogo, Maria Margarida; Cabral, Joaquim M. S.

    2016-01-01

    Human induced pluripotent stem (hiPS) cell culture using Essential 8™ xeno-free medium and the defined xeno-free matrix vitronectin was successfully implemented under adherent conditions. This matrix was able to support hiPS cell expansion either in coated plates or on polystyrene-coated microcarriers, while maintaining hiPS cell functionality and pluripotency. Importantly, scale-up of the microcarrier-based system was accomplished using a 50 mL spinner flask, under dynamic conditions. A three-level factorial design experiment was performed to identify optimal conditions in terms of a) initial cell density b) agitation speed, and c) to maximize cell yield in spinner flask cultures. A maximum cell yield of 3.5 is achieved by inoculating 55,000 cells/cm2 of microcarrier surface area and using 44 rpm, which generates a cell density of 1.4x106 cells/mL after 10 days of culture. After dynamic culture, hiPS cells maintained their typical morphology upon re-plating, exhibited pluripotency-associated marker expression as well as tri-lineage differentiation capability, which was verified by inducing their spontaneous differentiation through embryoid body formation, and subsequent downstream differentiation to specific lineages such as neural and cardiac fates was successfully accomplished. In conclusion, a scalable, robust and cost-effective xeno-free culture system was successfully developed and implemented for the scale-up production of hiPS cells. PMID:26999816

  19. Protein-scaffold Directed Nanoscale Assembly of T Cell Ligands: Artificial Antigen Presentation with Defined Valency, Density and Ratio.

    Science.gov (United States)

    Smith, Mason R; Tolbert, Stephanie V; Wen, Fei

    2018-05-07

    Tuning antigen presentation to T cells is a critical step in investigating key aspects of T cell activation. However, existing technologies have limited ability to control the spatial and stoichiometric organization of T cell ligands on 3D surfaces. Here, we developed an artificial antigen presentation platform based on protein-scaffold directed assembly that allows fine control over the spatial and stoichiometric organization of T cell ligands on a 3D yeast-cell surface. Using this system, we observed that the T cell activation threshold on a 3D surface is independent of peptide-major histocompatibility complex (pMHC) valency, but instead determined by the overall pMHC surface density. When intercellular adhesion molecule 1 (ICAM-1) was co-assembled with pMHC, it enhanced antigen recognition sensitivity by 6-fold. Further, T cells responded with different magnitudes to varying ratios of pMHC and ICAM-1 and exhibited a maximum response at a ratio of 15% pMHC and 85% ICAM-1, introducing an additional parameter for tuning T cell activation. This protein-scaffold directed assembly technology is readily transferrable to acellular surfaces for translational research as well as large-scale T-cell manufacturing.

  20. Mesenchymal stem cells induce mature dendritic cells into a novel Jagged-2-dependent regulatory dendritic cell population.

    Science.gov (United States)

    Zhang, Bin; Liu, Rui; Shi, Dan; Liu, Xingxia; Chen, Yuan; Dou, Xiaowei; Zhu, Xishan; Lu, Chunhua; Liang, Wei; Liao, Lianming; Zenke, Martin; Zhao, Robert C H

    2009-01-01

    Mesenchymal stem cells (MSCs), in addition to their multilineage differentiation, exert immunomodulatory effects on immune cells, even dendritic cells (DCs). However, whether they influence the destiny of full mature DCs (maDCs) remains controversial. Here we report that MSCs vigorously promote proliferation of maDCs, significantly reduce their expression of Ia, CD11c, CD80, CD86, and CD40 while increasing CD11b expression. Interestingly, though these phenotypes clearly suggest their skew to immature status, bacterial lipopolysaccharide (LPS) stimulation could not reverse this trend. Moreover, high endocytosic capacity, low immunogenicity, and strong immunoregulatory function of MSC-treated maDCs (MSC-DCs) were also observed. Furthermore we found that MSCs, partly via cell-cell contact, drive maDCs to differentiate into a novel Jagged-2-dependent regulatory DC population and escape their apoptotic fate. These results further support the role of MSCs in preventing rejection in organ transplantation and treatment of autoimmune disease.

  1. Medullospheres from DAOY, UW228 and ONS-76 cells: increased stem cell population and proteomic modifications.

    Science.gov (United States)

    Zanini, Cristina; Ercole, Elisabetta; Mandili, Giorgia; Salaroli, Roberta; Poli, Alice; Renna, Cristiano; Papa, Valentina; Cenacchi, Giovanna; Forni, Marco

    2013-01-01

    Medulloblastoma (MB) is an aggressive pediatric tumor of the Central Nervous System (CNS) usually treated according to a refined risk stratification. The study of cancer stem cells (CSC) in MB is a promising approach aimed at finding new treatment strategies. The CSC compartment was studied in three characterized MB cell lines (DAOY, UW228 and ONS-76) grown in standard adhesion as well as being grown as spheres, which enables expansion of the CSC population. MB cell lines, grown in adherence and as spheres, were subjected to morphologic analysis at the light and electron microscopic level, as well as cytofluorimetric determinations. Medullospheres (MBS) were shown to express increasingly immature features, along with the stem cells markers: CD133, Nestin and β-catenin. Proteomic analysis highlighted the differences between MB cell lines, demonstrating a unique protein profile for each cell line, and minor differences when grown as spheres. In MBS, MALDI-TOF also identified some proteins, that have been linked to tumor progression and resistance, such as Nucleophosmin (NPM). In addition, immunocytochemistry detected Sox-2 as a stemness marker of MBS, as well as confirming high NPM expression. Culture conditioning based on low attachment flasks and specialized medium may provide new data on the staminal compartment of CNS tumors, although a proteomic profile of CSC is still elusive for MB.

  2. Medullospheres from DAOY, UW228 and ONS-76 cells: increased stem cell population and proteomic modifications.

    Directory of Open Access Journals (Sweden)

    Cristina Zanini

    Full Text Available BACKGROUND: Medulloblastoma (MB is an aggressive pediatric tumor of the Central Nervous System (CNS usually treated according to a refined risk stratification. The study of cancer stem cells (CSC in MB is a promising approach aimed at finding new treatment strategies. METHODOLOGY/PRINCIPAL FINDINGS: The CSC compartment was studied in three characterized MB cell lines (DAOY, UW228 and ONS-76 grown in standard adhesion as well as being grown as spheres, which enables expansion of the CSC population. MB cell lines, grown in adherence and as spheres, were subjected to morphologic analysis at the light and electron microscopic level, as well as cytofluorimetric determinations. Medullospheres (MBS were shown to express increasingly immature features, along with the stem cells markers: CD133, Nestin and β-catenin. Proteomic analysis highlighted the differences between MB cell lines, demonstrating a unique protein profile for each cell line, and minor differences when grown as spheres. In MBS, MALDI-TOF also identified some proteins, that have been linked to tumor progression and resistance, such as Nucleophosmin (NPM. In addition, immunocytochemistry detected Sox-2 as a stemness marker of MBS, as well as confirming high NPM expression. CONCLUSIONS/SIGNIFICANCE: Culture conditioning based on low attachment flasks and specialized medium may provide new data on the staminal compartment of CNS tumors, although a proteomic profile of CSC is still elusive for MB.

  3. Defining population structure and genetic signatures of decline in the giant garter snake (Thamnophis gigas): implications for conserving threatened species within highly altered landscapes

    Science.gov (United States)

    Wood, Dustin A.; Halstead, Brian J.; Casazza, Michael L.; Hansen, Eric C.; Wylie, Glenn D.; Vandergast, Amy

    2015-01-01

    Anthropogenic habitat fragmentation can disrupt the ability of species to disperse across landscapes, which can alter the levels and distribution of genetic diversity within populations and negatively impact long-term viability. The giant gartersnake (Thamnophis gigas) is a state and federally threatened species that historically occurred in the wetland habitats of California’s Great Central Valley. Despite the loss of 93 % of historic wetlands throughout the Central Valley, giant gartersnakes continue to persist in relatively small, isolated patches of highly modified agricultural wetlands. Gathering information regarding genetic diversity and effective population size represents an essential component for conservation management programs aimed at this species. Previous mitochondrial sequence studies have revealed historical patterns of differentiation, yet little is known about contemporary population structure and diversity. On the basis of 15 microsatellite loci, we estimate population structure and compare indices of genetic diversity among populations spanning seven drainage basins within the Central Valley. We sought to understand how habitat loss may have affected genetic differentiation, genetic diversity and effective population size, and what these patterns suggest in terms of management and restoration actions. We recovered five genetic clusters that were consistent with regional drainage basins, although three northern basins within the Sacramento Valley formed a single genetic cluster. Our results show that northern drainage basin populations have higher connectivity than among central and southern basins populations, and that greater differentiation exists among the more geographically isolated populations in the central and southern portion of the species’ range. Genetic diversity measures among basins were significantly different, and were generally lower in southern basin populations. Levels of inbreeding and evidence of population

  4. Clinical, bacteriological, and histopathological characteristics of newly detected children with leprosy: A population based study in a defined rural and urban area of Maharashtra, Western India

    Directory of Open Access Journals (Sweden)

    Vanaja P Shetty

    2013-01-01

    Full Text Available Background: Leprosy has been a major public-health problem in many developing countries for centuries. According to the National Leprosy Elimination Programme report of March 2012, there were a total of about 0.13 million cases of leprosy in India, 9.7% of which were children. Numerous studies have investigated child leprosy amongst reported cases however, studies pertaining to proportion and characteristics of undetected childhood cases in the community are very few. Aim: To examine the clinical, bacteriological, and histopathological characteristics of newly detected child leprosy cases in the community. Methods: The population survey conducted from June to September 2007 and the defined rural areas, which included five primary health centers of Panvel Taluka, in Raigad district and urban areas, which included M-east ward of the municipal corporation of greater Mumbai of western Maharashtra, India. Results: House-to-house survey yielded 32 and 37 so far, undetected child cases of leprosy in the rural and urban region, and the prevalence rate was 10.5 and 1.5 per 10,000, respectively. The age of child leprosy cases detected, ranged from 3 to 14 years with a mean of 10.06 ± 3.35 years in the rural and 9.97 ± 3.12 years in the urban area. Most of the cases were paucibacillary (62%. A large proportion of children (49% had single skin lesion (SSL. Of the 19 SSL cases examined histopathologically, 15 (99% showed features of borderline tuberculoid, 1 (5% borderline lepromatous and 3 (16% had indeterminate type of leprosy. Tuberculoid leprosy was not seen in any, indicating less likelihood of self-healing. Overall, three cases had deformity (grade 1 = 1 and grade 2 = 2 and 31% of multibacillary cases were smear positive. Conclusion: The clinical, bacteriological, and histopathological characteristics of newly detected child cases in the community evidently indicate the grave nature of the problem of undetected child leprosy, recent active

  5. High-definition mapping of retroviral integration sites defines the fate of allogeneic T cells after donor lymphocyte infusion.

    Directory of Open Access Journals (Sweden)

    Claudia Cattoglio

    2010-12-01

    Full Text Available The infusion of donor lymphocytes transduced with a retroviral vector expressing the HSV-TK suicide gene in patients undergoing hematopoietic stem cell transplantation for leukemia/lymphoma promotes immune reconstitution and prevents infections and graft-versus-host disease. Analysis of the clonal dynamics of genetically modified lymphocytes in vivo is of crucial importance to understand the potential genotoxic risk of this therapeutic approach. We used linear amplification-mediated PCR and pyrosequencing to build a genome-wide, high-definition map of retroviral integration sites in the genome of peripheral blood T cells from two different donors and used gene expression profiling and bioinformatics to associate integration clusters to transcriptional activity and to genetic and epigenetic features of the T cell genome. Comparison with matched random controls and with integrations obtained from CD34(+ hematopoietic stem/progenitor cells showed that integration clusters occur within chromatin regions bearing epigenetic marks associated with active promoters and regulatory elements in a cell-specific fashion. Analysis of integration sites in T cells obtained ex vivo two months after infusion showed no evidence of integration-related clonal expansion or dominance, but rather loss of cells harboring integration events interfering with RNA post-transcriptional processing. The study shows that high-definition maps of retroviral integration sites are a powerful tool to analyze the fate of genetically modified T cells in patients and the biological consequences of retroviral transduction.

  6. CD49a Expression Defines Tissue-Resident CD8+ T Cells Poised for Cytotoxic Function in Human Skin

    DEFF Research Database (Denmark)

    Cheuk, Stanley; Schlums, Heinrich; Sérézal, Irène Gallais

    2017-01-01

    with vitiligo, where melanocytes are eradicated locally, CD8+CD49a+ Trm cells that constitutively expressed perforin and granzyme B accumulated both in the epidermis and dermis. Conversely, CD8+CD49a– Trm cells from psoriasis lesions predominantly generated IL-17 responses that promote local inflammation...

  7. Krox20 defines a subpopulation of cardiac neural crest cells contributing to arterial valves and bicuspid aortic valve.

    Science.gov (United States)

    Odelin, Gaëlle; Faure, Emilie; Coulpier, Fanny; Di Bonito, Maria; Bajolle, Fanny; Studer, Michèle; Avierinos, Jean-François; Charnay, Patrick; Topilko, Piotr; Zaffran, Stéphane

    2018-01-03

    Although cardiac neural crest cells are required at early stages of arterial valve development, their contribution during valvular leaflet maturation remains poorly understood. Here, we show in mouse that neural crest cells from pre-otic and post-otic regions make distinct contributions to the arterial valve leaflets. Genetic fate-mapping analysis of Krox20-expressing neural crest cells shows a large contribution to the borders and the interleaflet triangles of the arterial valves. Loss of Krox20 function results in hyperplastic aortic valve and partially penetrant bicuspid aortic valve formation. Similar defects are observed in neural crest Krox20 -deficient embryos. Genetic lineage tracing in Krox20 -/- mutant mice shows that endothelial-derived cells are normal, whereas neural crest-derived cells are abnormally increased in number and misplaced in the valve leaflets. In contrast, genetic ablation of Krox20 -expressing cells is not sufficient to cause an aortic valve defect, suggesting that adjacent cells can compensate this depletion. Our findings demonstrate a crucial role for Krox20 in arterial valve development and reveal that an excess of neural crest cells may be associated with bicuspid aortic valve. © 2018. Published by The Company of Biologists Ltd.

  8. Lin28a is a putative factor in regulating cancer stem cell-like properties in side population cells of oral squamous cell carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Hayashi, S.; Tanaka, J.; Okada, S.; Isobe, T.; Yamamoto, G.; Yasuhara, R.; Irie, T.; Akiyama, C.; Kohno, Y.; Tachikawa, T.; Mishima, K., E-mail: mishima-k@dent.showa-u.ac.jp

    2013-05-01

    Cancer stem cells (CSCs) are among the target cells of cancer therapy because they are uniquely involved in both cancer progression and sensitivity to chemotherapeutic agents. We identified side population (SP) cells, which are known to be an enriched population of CSC, in five oral squamous cell carcinoma (OSCC) cells (SCC9, SCC25, TOSCC7, TOSCC17, and TOSCC23). The percentages of SP cells ranged from 0% to 3.3%, with TOSCC23 cells showing the highest percentages of SP cells (3.3% of the total cell population). The SP cells isolated from TOSCC23 cells also showed greater cell proliferation and invasion compared to non-SP (MP) cells. Therefore, our initial findings suggested that SP cells were enriched for CSC-like cells. Furthermore, DNA microarray analysis revealed that the expression of cell proliferation-related and anti-apoptotic genes was greater in SP cells compared to MP cells. We focused on Lin28a, which showed the highest expression (approximately 22-fold) among the upregulated genes. The overexpression of Lin28a in TOSCC23 cells increased their proliferation, colony formation, and invasion. These findings suggest that Lin28a is an appropriate CSC target molecule for OSCC treatment - Highlights: ► Lin28a is a SP cell-specific factor in oral squamous cell carcinoma (OSCC) cells. ► SP cells in OSCC cells show cancer stem cell-like properties. ► Lin28a regulates OSCC proliferative and invasive activities.

  9. Lin28a is a putative factor in regulating cancer stem cell-like properties in side population cells of oral squamous cell carcinoma

    International Nuclear Information System (INIS)

    Hayashi, S.; Tanaka, J.; Okada, S.; Isobe, T.; Yamamoto, G.; Yasuhara, R.; Irie, T.; Akiyama, C.; Kohno, Y.; Tachikawa, T.; Mishima, K.

    2013-01-01

    Cancer stem cells (CSCs) are among the target cells of cancer therapy because they are uniquely involved in both cancer progression and sensitivity to chemotherapeutic agents. We identified side population (SP) cells, which are known to be an enriched population of CSC, in five oral squamous cell carcinoma (OSCC) cells (SCC9, SCC25, TOSCC7, TOSCC17, and TOSCC23). The percentages of SP cells ranged from 0% to 3.3%, with TOSCC23 cells showing the highest percentages of SP cells (3.3% of the total cell population). The SP cells isolated from TOSCC23 cells also showed greater cell proliferation and invasion compared to non-SP (MP) cells. Therefore, our initial findings suggested that SP cells were enriched for CSC-like cells. Furthermore, DNA microarray analysis revealed that the expression of cell proliferation-related and anti-apoptotic genes was greater in SP cells compared to MP cells. We focused on Lin28a, which showed the highest expression (approximately 22-fold) among the upregulated genes. The overexpression of Lin28a in TOSCC23 cells increased their proliferation, colony formation, and invasion. These findings suggest that Lin28a is an appropriate CSC target molecule for OSCC treatment - Highlights: ► Lin28a is a SP cell-specific factor in oral squamous cell carcinoma (OSCC) cells. ► SP cells in OSCC cells show cancer stem cell-like properties. ► Lin28a regulates OSCC proliferative and invasive activities

  10. Comparative Approach to Define Increased Regulatory T Cells in Different Cancer Subtypes by Combined Assessment of CD127 and FOXP3

    Directory of Open Access Journals (Sweden)

    Marc Beyer

    2011-01-01

    Full Text Available In recent years an increase of functional CD4+CD25+ regulatory T cells (Treg cells has been established for patients with solid tumors, acute leukemias, and lymphomas. We have reported an expanded pool of CD4+CD25high Treg cells in patients with chronic lymphatic leukemia (CLL, multiple myeloma (MM as well as its premalignant precursor monoclonal gammopathy of undetermined significance (MGUS. In healthy individuals, low-level expression of CD127 on T cells in addition to the expression of FOXP3 has been associated with Treg cells. Here, we demonstrate that the expanded FOXP3+ T-cell population in patients with colorectal cancer, CLL, MGUS, MM, follicular lymphoma, and Hodgkin's disease are exclusively CD127low Treg cells and were strongly suppressive. A significant portion of CD127lowFOXP3+ Treg cells expressed only low levels of CD25 suggesting that the previously reported expansion of CD25+ Treg cells underestimates the true expansion. The assessment of CCR7 and CD45RA expression on the expanded CD4+CD127lowFOXP3+ Treg cells revealed an increase of both naïve as well as central and effector memory Treg cells in peripheral blood. Our data strongly support superiority of combined CD127 and FOXP3 analysis in comparison to CD25 and FOXP3 assessment for further quantification of Treg cells in malignant diseases.

  11. Molecular crowding defines a common origin for the Warburg effect in proliferating cells and the lactate threshold in muscle physiology.

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    Alexei Vazquez

    2011-04-01

    Full Text Available Aerobic glycolysis is a seemingly wasteful mode of ATP production that is seen both in rapidly proliferating mammalian cells and highly active contracting muscles, but whether there is a common origin for its presence in these widely different systems is unknown. To study this issue, here we develop a model of human central metabolism that incorporates a solvent capacity constraint of metabolic enzymes and mitochondria, accounting for their occupied volume densities, while assuming glucose and/or fatty acid utilization. The model demonstrates that activation of aerobic glycolysis is favored above a threshold metabolic rate in both rapidly proliferating cells and heavily contracting muscles, because it provides higher ATP yield per volume density than mitochondrial oxidative phosphorylation. In the case of muscle physiology, the model also predicts that before the lactate switch, fatty acid oxidation increases, reaches a maximum, and then decreases to zero with concomitant increase in glucose utilization, in agreement with the empirical evidence. These results are further corroborated by a larger scale model, including biosynthesis of major cell biomass components. The larger scale model also predicts that in proliferating cells the lactate switch is accompanied by activation of glutaminolysis, another distinctive feature of the Warburg effect. In conclusion, intracellular molecular crowding is a fundamental constraint for cell metabolism in both rapidly proliferating- and non-proliferating cells with high metabolic demand. Addition of this constraint to metabolic flux balance models can explain several observations of mammalian cell metabolism under steady state conditions.

  12. Receptors for corticotropin-releasing hormone in human pituitary: Binding characteristics and autoradiographic localization to immunocytochemically defined proopiomelanocortin cells

    Energy Technology Data Exchange (ETDEWEB)

    Smets, G.; Vauquelin, G.; Moons, L.; Smitz, J.; Kloeppel, G. (Department of Experimental Pathology, Vrije Universiteit Brussel (Belgium))

    1991-08-01

    Using autoradiography combined with immunocytochemistry, the authors demonstrated that the target cells of CRH in the human pituitary were proopiomelanocortin cells. Scatchard analysis of (125I)Tyr0-oCRH saturation binding revealed the presence of one class of saturable, high affinity sites on pituitary tissue homogenate. The equilibrium dissociation constant (Kd) for (125I)Tyr0-oCRH ranged from 1.1-1.6 nM, and the receptor density was between 200-350 fmol/mg protein. Fixation of cryostat sections with 4% paraformaldehyde before tracer incubation improved both tissue preservation and localization of the CRH receptor at the cellular level. Additional postfixation with 1% glutaraldehyde inhibited tracer diffusion during subsequent immunocytochemistry and autoradiography. (125I)Tyr0-oCRH was found in cytoplasmic inclusions or at the cell periphery of ACTH/beta-endorphin cells in the anterior pituitary. Single cells of the posterior pituitary were also CRH receptor positive. Cells staining for PRL or GH were CRH receptor negative. They conclude that CRH binds only to high affinity receptors on ACTH/{beta}-endorphin cells in the human pituitary.

  13. Defining the steps that lead to cancer: replicative telomere erosion, aneuploidy and an epigenetic maturation arrest of tissue stem cells.

    Science.gov (United States)

    Stindl, Reinhard

    2008-01-01

    Recently, an influential sequencing study found that more than 1700 genes had non-silent mutations in either a breast or colorectal cancer, out of just 11 breast and 11 colorectal tumor samples. This is not surprising given the fact that genomic instability is the hallmark of cancer cells. The plethora of genomic alterations found in every carcinoma does not obey the 'law of genotype-phenotype correlation', since the same histological subtype of cancer harbors different gene mutations and chromosomal aberrations in every patient. In an attempt to make sense out of the observed genetic and chromosomal chaos in cancer, I propose a cascade model. According to this model, tissue regeneration depends on the proliferation and serial activation of stem cells. Replicative telomere erosion limits the proliferative life span of adult stem cells and results in the Hayflick limit (M1). However, local tissue exhaustion or old age might promote the activation of M1-deficient tissue stem cells. Extended proliferation of these cells leads to telomere-driven chromosomal instability and aneuploidy (abnormal balance of chromosomes and/or chromosome material). Several of the aforementioned steps have been already described in the literature. However, in contrast to common theories, it is proposed here that the genomic damage blocks the epigenetic differentiation switch. As a result of aneuploidy, differentiation-specific genes cannot be activated by modification of methylation patterns. Consequently, the phenotype of cancer tissue is largely determined by the epigenetic maturation arrest of tissue stem cells, which in addition enables a fraction of cancer cells to proliferate, invade and metastasize, as normal adult stem cells do. The new model combines genetic and epigenetic alterations of cancer cells in one causative cascade and offers an explanation for why identical histologic cancer types harbor a confusing variety of chromosomal and gene aberrations. The Viennese Cascade, as

  14. Development of a chemically defined platform fed-batch culture media for monoclonal antibody-producing CHO cell lines with optimized choline content.

    Science.gov (United States)

    Kuwae, Shinobu; Miyakawa, Ichiko; Doi, Tomohiro

    2018-01-11

    A chemically defined platform basal medium and feed media were developed using a single Chinese hamster ovary (CHO) cell line that produces a monoclonal antibody (mAb). Cell line A, which showed a peak viable cell density of 5.9 × 10 6  cells/mL and a final mAb titer of 0.5 g/L in batch culture, was selected for the platform media development. Stoichiometrically balanced feed media were developed using glucose as an indicator of cell metabolism to determine the feed rates of all other nutrients. A fed-batch culture of cell line A using the platform fed-batch medium yielded a 6.4 g/L mAb titer, which was 12-fold higher than that of the batch culture. To examine the applicability of the platform basal medium and feed media, three other cell lines (A16, B, and C) that produce mAbs were cultured using the platform fed-batch medium, and they yielded mAb titers of 8.4, 3.3, and 6.2 g/L, respectively. The peak viable cell densities of the three cell lines ranged from 1.3 × 10 7 to 1.8 × 10 7  cells/mL. These results show that the nutritionally balanced fed-batch medium and feeds worked well for other cell lines. During the medium development, we found that choline limitation caused a lower cell viability, a lower mAb titer, a higher mAb aggregate content, and a higher mannose-5 content. The optimal choline chloride to glucose ratio for the CHO cell fed-batch culture was determined. Our platform basal medium and feed media will shorten the medium-development time for mAb-producing cell lines.

  15. Intent-to-treat leukemia remission by CD19 CAR T cells of defined formulation and dose in children and young adults.

    Science.gov (United States)

    Gardner, Rebecca A; Finney, Olivia; Annesley, Colleen; Brakke, Hannah; Summers, Corinne; Leger, Kasey; Bleakley, Marie; Brown, Christopher; Mgebroff, Stephanie; Kelly-Spratt, Karen S; Hoglund, Virginia; Lindgren, Catherine; Oron, Assaf P; Li, Daniel; Riddell, Stanley R; Park, Julie R; Jensen, Michael C

    2017-06-22

    Transitioning CD19-directed chimeric antigen receptor (CAR) T cells from early-phase trials in relapsed patients to a viable therapeutic approach with predictable efficacy and low toxicity for broad application among patients with high unmet need is currently complicated by product heterogeneity resulting from transduction of undefined T-cell mixtures, variability of transgene expression, and terminal differentiation of cells at the end of culture. A phase 1 trial of 45 children and young adults with relapsed or refractory B-lineage acute lymphoblastic leukemia was conducted using a CD19 CAR product of defined CD4/CD8 composition, uniform CAR expression, and limited effector differentiation. Products meeting all defined specifications occurred in 93% of enrolled patients. The maximum tolerated dose was 10 6 CAR T cells per kg, and there were no deaths or instances of cerebral edema attributable to product toxicity. The overall intent-to-treat minimal residual disease-negative (MRD - ) remission rate for this phase 1 study was 89%. The MRD - remission rate was 93% in patients who received a CAR T-cell product and 100% in the subset of patients who received fludarabine and cyclophosphamide lymphodepletion. Twenty-three percent of patients developed reversible severe cytokine release syndrome and/or reversible severe neurotoxicity. These data demonstrate that manufacturing a defined-composition CD19 CAR T cell identifies an optimal cell dose with highly potent antitumor activity and a tolerable adverse effect profile in a cohort of patients with an otherwise poor prognosis. This trial was registered at www.clinicaltrials.gov as #NCT02028455. © 2017 by The American Society of Hematology.

  16. Endothelial Progenitor Cell Fraction Contained in Bone Marrow-Derived Mesenchymal Stem Cell Populations Impairs Osteogenic Differentiation

    Directory of Open Access Journals (Sweden)

    Fabian Duttenhoefer

    2015-01-01

    Full Text Available In bone tissue engineering (TE endothelial cell-osteoblast cocultures are known to induce synergies of cell differentiation and activity. Bone marrow mononucleated cells (BMCs are a rich source of mesenchymal stem cells (MSCs able to develop an osteogenic phenotype. Endothelial progenitor cells (EPCs are also present within BMC. In this study we investigate the effect of EPCs present in the BMC population on MSCs osteogenic differentiation. Human BMCs were isolated and separated into two populations. The MSC population was selected through plastic adhesion capacity. EPCs (CD34+ and CD133+ were removed from the BMC population and the resulting population was named depleted MSCs. Both populations were cultured over 28 days in osteogenic medium (Dex+ or medium containing platelet lysate (PL. MSC population grew faster than depleted MSCs in both media, and PL containing medium accelerated the proliferation for both populations. Cell differentiation was much higher in Dex+ medium in both cases. Real-time RT-PCR revealed upregulation of osteogenic marker genes in depleted MSCs. Higher values of ALP activity and matrix mineralization analyses confirmed these results. Our study advocates that absence of EPCs in the MSC population enables higher osteogenic gene expression and matrix mineralization and therefore may lead to advanced bone neoformation necessary for TE constructs.

  17. What Population Reveals about Individual Cell Identity: Single-Cell Parameter Estimation of Models of Gene Expression in Yeast.

    Directory of Open Access Journals (Sweden)

    Artémis Llamosi

    2016-02-01

    Full Text Available Significant cell-to-cell heterogeneity is ubiquitously observed in isogenic cell populations. Consequently, parameters of models of intracellular processes, usually fitted to population-averaged data, should rather be fitted to individual cells to obtain a population of models of similar but non-identical individuals. Here, we propose a quantitative modeling framework that attributes specific parameter values to single cells for a standard model of gene expression. We combine high quality single-cell measurements of the response of yeast cells to repeated hyperosmotic shocks and state-of-the-art statistical inference approaches for mixed-effects models to infer multidimensional parameter distributions describing the population, and then derive specific parameters for individual cells. The analysis of single-cell parameters shows that single-cell identity (e.g. gene expression dynamics, cell size, growth rate, mother-daughter relationships is, at least partially, captured by the parameter values of gene expression models (e.g. rates of transcription, translation and degradation. Our approach shows how to use the rich information contained into longitudinal single-cell data to infer parameters that can faithfully represent single-cell identity.

  18. A defined and xeno-free culture method enabling the establishment of clinical-grade human embryonic, induced pluripotent and adipose stem cells.

    Directory of Open Access Journals (Sweden)

    Kristiina Rajala

    2010-04-01

    Full Text Available The growth of stem cells in in vitro conditions requires optimal balance between signals mediating cell survival, proliferation, and self-renewal. For clinical application of stem cells, the use of completely defined conditions and elimination of all animal-derived materials from the establishment, culture, and differentiation processes is desirable.Here, we report the development of a fully defined xeno-free medium (RegES, capable of supporting the expansion of human embryonic stem cells (hESC, induced pluripotent stem cells (iPSC and adipose stem cells (ASC. We describe the use of the xeno-free medium in the derivation and long-term (>80 passages culture of three pluripotent karyotypically normal hESC lines: Regea 06/015, Regea 07/046, and Regea 08/013. Cardiomyocytes and neural cells differentiated from these cells exhibit features characteristic to these cell types. The same formulation of the xeno-free medium is capable of supporting the undifferentiated growth of iPSCs on human feeder cells. The characteristics of the pluripotent hESC and iPSC lines are comparable to lines derived and cultured in standard undefined culture conditions. In the culture of ASCs, the xeno-free medium provided significantly higher proliferation rates than ASCs cultured in medium containing allogeneic human serum (HS, while maintaining the differentiation potential and characteristic surface marker expression profile of ASCs, although significant differences in the surface marker expression of ASCs cultured in HS and RegES media were revealed.Our results demonstrate that human ESCs, iPSCs and ASCs can be maintained in the same defined xeno-free medium formulation for a prolonged period of time while maintaining their characteristics, demonstrating the applicability of the simplified xeno-free medium formulation for the production of clinical-grade stem cells. The basic xeno-free formulation described herein has the potential to be further optimized for specific

  19. Defined three-dimensional culture conditions mediate efficient induction of definitive endoderm lineage from human umbilical cord Wharton's jelly mesenchymal stem cells.

    Science.gov (United States)

    Al Madhoun, Ashraf; Ali, Hamad; AlKandari, Sarah; Atizado, Valerie Lopez; Akhter, Nadeem; Al-Mulla, Fahd; Atari, Maher

    2016-11-16

    Wharton's jelly-derived mesenchymal stem cells (WJ-MSCs) are gaining increasing interest as an alternative source of stem cells for regenerative medicine applications. Definitive endoderm (DE) specification is a prerequisite for the development of vital organs such as liver and pancreas. Hence, efficient induction of the DE lineage from stem cells is crucial for subsequent generation of clinically relevant cell types. Here we present a defined 3D differentiation protocol of WJ-MSCs into DE cells. WJ-MSCs were cultured in suspension to generate spheroids, about 1500 cells each, for 7 days. The serum-free differentiation media contained specific growth factors, cytokines, and small molecules that specifically regulate signaling pathways including sonic hedgehog, bone morphogenetic protein, Activin/Wnt, and Notch. We obtained more than 85 % DE cells as shown with FACS analysis using antibodies directed against the DE marker CXCR4. In addition, biochemical and molecular analysis of bona-fide DE markers revealed a time-course induction of Sox17, CXCR4, and FoxA2. Focused PCR-based array also indicated a specific induction into the DE lineage. In this study, we report an efficient serum-free protocol to differentiate WJ-MSCs into DE cells utilizing 3D spheroid formation. Our approach might aid in the development of new protocols to obtain DE-derivative lineages including liver-like and pancreatic insulin-producing cells.

  20. Homeostasis of peripheral CD4+ T cells: IL-2R alpha and IL-2 shape a population of regulatory cells that controls CD4+ T cell numbers

    NARCIS (Netherlands)

    Almeida, Afonso R. M.; Legrand, Nicolas; Papiernik, Martine; Freitas, António A.

    2002-01-01

    We show that the lymphoid hyperplasia observed in IL-2Ralpha- and IL-2-deficient mice is due to the lack of a population of regulatory cells essential for CD4 T cell homeostasis. In chimeras reconstituted with bone marrow cells from IL-2Ralpha-deficient donors, restitution of a population of

  1. The effect of porosity on cell ingrowth into accurately defined, laser-made, polylactide-based 3D scaffolds

    Energy Technology Data Exchange (ETDEWEB)

    Danilevicius, Paulius; Georgiadi, Leoni [Foundation for Research and Technology Hellas (FORTH), Institute of Electronic Structure and Laser (IESL), N Plastira 100, 70013 Heraklion (Greece); Pateman, Christopher J.; Claeyssens, Frederik [Kroto Research Institute, Department of Materials Science and Engineering, University of Sheffield, Broad Lane, Sheffield S3 7HQ (United Kingdom); Chatzinikolaidou, Maria, E-mail: mchatzin@materials.uoc.gr [Foundation for Research and Technology Hellas (FORTH), Institute of Electronic Structure and Laser (IESL), N Plastira 100, 70013 Heraklion (Greece); Department of Materials Science and Technology, University of Crete, PO Box 2208, 71303 Heraklion (Greece); Farsari, Maria, E-mail: mfarsari@iesl.forth.gr [Foundation for Research and Technology Hellas (FORTH), Institute of Electronic Structure and Laser (IESL), N Plastira 100, 70013 Heraklion (Greece)

    2015-05-01

    Highlights: • We studied the porosity of laser-made 3D scaffolds on MC3T3-E1 pre-osteoblastic cells. • We made polylactide 3D scaffolds with pores 25–110 μm. - Abstract: The aim of this study is to demonstrate the accuracy required for the investigation of the role of solid scaffolds’ porosity in cell proliferation. We therefore present a qualitative investigation into the effect of porosity on MC3T3-E1 pre-osteoblastic cell ingrowth of three-dimensional (3D) scaffolds fabricated by direct femtosecond laser writing. The material we used is a purpose made photosensitive pre-polymer based on polylactide. We designed and fabricated complex, geometry-controlled 3D scaffolds with pore sizes ranging from 25 to 110 μm, representing porosities 70%, 82%, 86%, and 90%. The 70% porosity scaffolds did not support cell growth initially and in the long term. For the other porosities, we found a strong adhesion of the pre-osteoblastic cells from the first hours after seeding and a remarkable proliferation increase after 3 weeks and up to 8 weeks. The 86% porosity scaffolds exhibited a higher efficiency compared to 82% and 90%. In addition, bulk material degradation studies showed that the employed, highly-acrylated polylactide is degradable. These findings support the potential use of the proposed material and the scaffold fabrication technique in bone tissue engineering.

  2. Non-integrating episomal plasmid-based reprogramming of human amniotic fluid stem cells into induced pluripotent stem cells in chemically defined conditions

    NARCIS (Netherlands)

    Slamecka, J.; Salimova, L.; McClellan, S.; van Kelle, M.; Kehl, D.; Laurini, J.; Cinelli, P.; Owen, L.; Hoerstrup, S.P.; Weber, B.

    2016-01-01

    Amniotic fluid stem cells (AFSC) represent an attractive potential cell source for fetal and pediatric cell-based therapies. However, upgrading them to pluripotency confers refractoriness toward senescence, higher proliferation rate and unlimited differentiation potential. AFSC were observed to

  3. A sub-population of circulating porcine gammadelta T cells can act as professional antigen presenting cells.

    Science.gov (United States)

    Takamatsu, H-H; Denyer, M S; Wileman, T E

    2002-09-10

    A sub-population of circulating porcine gammadelta T cells express cell surface antigens associated with antigen presenting cells (APCs), and are able to take up soluble antigen very effectively. Functional antigen presentation by gammadelta T cells to memory helper T cells was studied by inbred pig lymphocytes immunised with ovalbumin (OVA). After removing all conventional APCs from the peripheral blood of immunised pigs, the remaining lymphocytes still proliferated when stimulated with OVA. When gammadelta T cells were further depleted, OVA specific proliferation was abolished, but reconstitution with gammadelta T cells restored proliferation. The proliferation was blocked by monoclonal antibodies (mAb) against MHC class II or CD4, and by pre-treatment of gammadelta T cells with chloroquine. These results indicate that a sub-population of circulating porcine gammadelta T cells act as APCs and present antigen via MHC class II.

  4. Temporal network based analysis of cell specific vein graft transcriptome defines key pathways and hub genes in implantation injury.

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    Manoj Bhasin

    Full Text Available Vein graft failure occurs between 1 and 6 months after implantation due to obstructive intimal hyperplasia, related in part to implantation injury. The cell-specific and temporal response of the transcriptome to vein graft implantation injury was determined by transcriptional profiling of laser capture microdissected endothelial cells (EC and medial smooth muscle cells (SMC from canine vein grafts, 2 hours (H to 30 days (D following surgery. Our results demonstrate a robust genomic response beginning at 2 H, peaking at 12-24 H, declining by 7 D, and resolving by 30 D. Gene ontology and pathway analyses of differentially expressed genes indicated that implantation injury affects inflammatory and immune responses, apoptosis, mitosis, and extracellular matrix reorganization in both cell types. Through backpropagation an integrated network was built, starting with genes differentially expressed at 30 D, followed by adding upstream interactive genes from each prior time-point. This identified significant enrichment of IL-6, IL-8, NF-κB, dendritic cell maturation, glucocorticoid receptor, and Triggering Receptor Expressed on Myeloid Cells (TREM-1 signaling, as well as PPARα activation pathways in graft EC and SMC. Interactive network-based analyses identified IL-6, IL-8, IL-1α, and Insulin Receptor (INSR as focus hub genes within these pathways. Real-time PCR was used for the validation of two of these genes: IL-6 and IL-8, in addition to Collagen 11A1 (COL11A1, a cornerstone of the backpropagation. In conclusion, these results establish causality relationships clarifying the pathogenesis of vein graft implantation injury, and identifying novel targets for its prevention.

  5. Transcriptional profiling at whole population and single cell levels reveals somatosensory neuron molecular diversity

    Science.gov (United States)

    Chiu, Isaac M; Barrett, Lee B; Williams, Erika K; Strochlic, David E; Lee, Seungkyu; Weyer, Andy D; Lou, Shan; Bryman, Gregory S; Roberson, David P; Ghasemlou, Nader; Piccoli, Cara; Ahat, Ezgi; Wang, Victor; Cobos, Enrique J; Stucky, Cheryl L; Ma, Qiufu; Liberles, Stephen D; Woolf, Clifford J

    2014-01-01

    The somatosensory nervous system is critical for the organism's ability to respond to mechanical, thermal, and nociceptive stimuli. Somatosensory neurons are functionally and anatomically diverse but their molecular profiles are not well-defined. Here, we used transcriptional profiling to analyze the detailed molecular signatures of dorsal root ganglion (DRG) sensory neurons. We used two mouse reporter lines and surface IB4 labeling to purify three major non-overlapping classes of neurons: 1) IB4+SNS-Cre/TdTomato+, 2) IB4−SNS-Cre/TdTomato+, and 3) Parv-Cre/TdTomato+ cells, encompassing the majority of nociceptive, pruriceptive, and proprioceptive neurons. These neurons displayed distinct expression patterns of ion channels, transcription factors, and GPCRs. Highly parallel qRT-PCR analysis of 334 single neurons selected by membership of the three populations demonstrated further diversity, with unbiased clustering analysis identifying six distinct subgroups. These data significantly increase our knowledge of the molecular identities of known DRG populations and uncover potentially novel subsets, revealing the complexity and diversity of those neurons underlying somatosensation. DOI: http://dx.doi.org/10.7554/eLife.04660.001 PMID:25525749

  6. An Isochemogenic Set of Inhibitors To Define the Therapeutic Potential of Histone Deacetylases in β-Cell Protection

    DEFF Research Database (Denmark)

    Wagner, Florence F; Lundh, Morten; Kaya, Taner

    2016-01-01

    Modulation of histone deacetylase (HDAC) activity has been implicated as a potential therapeutic strategy for multiple diseases. However, it has been difficult to dissect the role of individual HDACs due to a lack of selective small-molecule inhibitors. Here, we report the synthesis of a series...... of highly potent and isoform-selective class I HDAC inhibitors, rationally designed by exploiting minimal structural changes to the clinically experienced HDAC inhibitor CI-994. We used this toolkit of isochemogenic or chemically matched inhibitors to probe the role of class I HDACs in β-cell pathobiology...... pancreatic β-cells from inflammatory cytokines and nutrient overload in diabetes....

  7. A Novel View of the Adult Stem Cell Compartment From the Perspective of a Quiescent Population of Very Small Embryonic-Like Stem Cells.

    Science.gov (United States)

    Ratajczak, Mariusz Z; Ratajczak, Janina; Suszynska, Malwina; Miller, Donald M; Kucia, Magda; Shin, Dong-Myung

    2017-01-06

    Evidence has accumulated that adult hematopoietic tissues and other organs contain a population of dormant stem cells (SCs) that are more primitive than other, already restricted, monopotent tissue-committed SCs (TCSCs). These observations raise several questions, such as the developmental origin of these cells, their true pluripotent or multipotent nature, which surface markers they express, how they can be efficiently isolated from adult tissues, and what role they play in the adult organism. The phenotype of these cells and expression of some genes characteristic of embryonic SCs, epiblast SCs, and primordial germ cells suggests their early-embryonic deposition in developing tissues as precursors of adult SCs. In this review, we will critically discuss all these questions and the concept that small dormant SCs related to migratory primordial germ cells, described as very small embryonic-like SCs, are deposited during embryogenesis in bone marrow and other organs as a backup population for adult tissue-committed SCs and are involved in several processes related to tissue or organ rejuvenation, aging, and cancerogenesis. The most recent results on successful ex vivo expansion of human very small embryonic-like SC in chemically defined media free from feeder-layer cells open up new and exciting possibilities for their application in regenerative medicine. © 2017 American Heart Association, Inc.

  8. Requirements for future control room and visualisation features in the Web-of-Cells framework defined in the ELECTRA project

    DEFF Research Database (Denmark)

    Tornelli, Carlo; Zuelli, Roberto; Marinell, Mattia

    2017-01-01

    project, that proposes a new Web-of-Cell (WoC) power system control architecture. Dedicated visualisation features are proposed, aimed to support the control room operators activities in a WoC-oriented approach. Furthermore, the work takes into account the point of view of network operators about future...

  9. High content screening of defined chemical libraries using normal and glioma-derived neural stem cell lines.

    Science.gov (United States)

    Danovi, Davide; Folarin, Amos A; Baranowski, Bart; Pollard, Steven M

    2012-01-01

    Small molecules with potent biological effects on the fate of normal and cancer-derived stem cells represent both useful research tools and new drug leads for regenerative medicine and oncology. Long-term expansion of mouse and human neural stem cells is possible using adherent monolayer culture. These cultures represent a useful cellular resource to carry out image-based high content screening of small chemical libraries. Improvements in automated microscopy, desktop computational power, and freely available image processing tools, now means that such chemical screens are realistic to undertake in individual academic laboratories. Here we outline a cost effective and versatile time lapse imaging strategy suitable for chemical screening. Protocols are described for the handling and screening of human fetal Neural Stem (NS) cell lines and their malignant counterparts, Glioblastoma-derived neural stem cells (GNS). We focus on identification of cytostatic and cytotoxic "hits" and discuss future possibilities and challenges for extending this approach to assay lineage commitment and differentiation. Copyright © 2012 Elsevier Inc. All rights reserved.

  10. The interplay between surfaces and soluble factors define the immunologic and angiogenic properties of myeloid dendritic cells

    Directory of Open Access Journals (Sweden)

    Mansfield Kristen

    2011-06-01

    Full Text Available Abstract Background Dendritic cells (DCs are antigen presenting cells capable of inducing specific immune responses against microbial infections, transplant antigens, or tumors. Interestingly, microenvironment conditions such as those present in tumor settings might induce a DC phenotype that is poorly immunogenic and with the capability of promoting angiogenesis. We hypothesize that this plasticity may be caused not only by the action of specific cytokines or growth factors but also by the properties of the surfaces with which they interact, such as extracellular matrix (ECM components. Results Herewith we studied the effect of different surfaces and soluble factors on the biology of DCs. To accomplish this, we cultured murine myeloid(m DCs on surfaces coated with fibronectin, collagen I, gelatin, and Matrigel using poly-D-lysine and polystyrene as non-biological surfaces. Further, we cultured these cells in the presence of regular DC medium (RPMI 10% FBS or commercially available endothelial medium (EGM-2. We determined that mDCs could be kept in culture up to 3 weeks in these conditions, but only in the presence of GM-CSF. We were able to determine that long-term DC cultures produce an array of angiogenic factors, and that some of these cultures still retain the capability to induce T cell responses. Conclusions Altogether these data indicate that in order to design DC-based vaccines or treatments focused on changing the phenotype of DCs associated with diseases such as cancer or atherosclerosis, it becomes necessary to fully investigate the microenvironment in which these cells are present or will be delivered.

  11. Application of High-Resolution Magic-Angle Spinning NMR Spectroscopy to Define the Cell Uptake of MRI Contrast Agents

    Science.gov (United States)

    Calabi, Luisella; Alfieri, Goffredo; Biondi, Luca; De Miranda, Mario; Paleari, Lino; Ghelli, Stefano

    2002-06-01

    A new method, based on proton high-resolution magic-angle spinning ( 1H HR-MAS) NMR spectroscopy, has been employed to study the cell uptake of magnetic resonance imaging contrast agents (MRI-CAs). The method was tested on human red blood cells (HRBC) and white blood cells (HWBC) by using three gadolinium complexes, widely used in diagnostics, Gd-BOPTA, Gd-DTPA, and Gd-DOTA, and the analogous complexes obtained by replacing Gd(III) with Dy(III), Nd(III), and Tb(III) (i.e., complexes isostructural to the ones of gadolinium but acting as shift agents). The method is based on the evaluation of the magnetic effects, line broadening, or induced lanthanide shift (LIS) caused by these complexes on NMR signals of intra- and extracellular water. Since magnetic effects are directly linked to permeability, this method is direct. In all the tests, these magnetic effects were detected for the extracellular water signal only, providing a direct proof that these complexes are not able to cross the cell membrane. Line broadening effects (i.e., the use of gadolinium complexes) only allow qualitative evaluations. On the contrary, LIS effects can be measured with high precision and they can be related to the concentration of the paramagnetic species in the cellular compartments. This is possible because the HR-MAS technique provides the complete elimination of bulk magnetic susceptibility (BMS) shift and the differentiation of extra- and intracellular water signals. Thus with this method, the rapid quantification of the MRI-CA amount inside and outside the cells is actually feasible.

  12. Soluble endothelial cell-selective adhesion molecule and incident cardiovascular events in a multiethnic population.

    Science.gov (United States)

    Ren, Hao-Yu; Khera, Amit; de Lemos, James A; Ayers, Colby R; Rohatgi, Anand

    2017-09-01

    Cell adhesion molecules are key regulators of atherosclerotic plaque development, but circulating levels of soluble fragments, such as intercellular adhesion molecule (sICAM-1) and vascular cell adhesion molecule (sVCAM-1), have yielded conflicting associations with atherosclerotic cardiovascular disease (ASCVD). Endothelial cell-selective adhesion molecule (ESAM) is expressed exclusively in platelets and endothelial cells, and soluble ESAM (sESAM) levels have been associated with prevalent subclinical atherosclerosis. We therefore hypothesized that sESAM would be associated with incident ASCVD. sESAM, sICAM-1, and sVCAM-1 were measured in 2,442 participants without CVD in the Dallas Heart Study, a probability-based population sample aged 30-65 years enrolled between 2000 and 2002. ASCVD was defined as first myocardial infarction, stroke, coronary revascularization, or CV death. A total of 162 ASCVD events were analyzed over 10.4 years. Increasing sESAM was associated with ASCVD, independent of risk factors (HR Q4 vs Q1: 2.7, 95% CI 1.6-4.6). Serial adjustment for renal function, sICAM-1, VCAM-1, and prevalent coronary calcium did not attenuate these associations. Continuous ESAM demonstrated similar findings (HR 1.31, 95% CI 1.2-1.4). Addition of sESAM to traditional risk factors improved discrimination and reclassification (delta c-index: P = .009; integrated-discrimination-improvement index P = .001; net reclassification index = 0.42, 95% CI 0.15-0.68). Neither sICAM-1 nor sVCAM-1 was independently associated with ASCVD. sESAM but not sICAM-1 or sVCAM-1 levels are associated with incident ASCVD. Further studies are warranted to investigate the role of sESAM in ASCVD. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Mapping the distinctive populations of lymphatic endothelial cells in different zones of human lymph nodes.

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    Saem Mul Park

    Full Text Available The lymphatic sinuses in human lymph nodes (LNs are crucial to LN function yet their structure remains poorly defined. Much of our current knowledge of lymphatic sinuses derives from rodent models, however human LNs differ substantially in their sinus structure, most notably due to the presence of trabeculae and trabecular lymphatic sinuses that rodent LNs lack. Lymphatic sinuses are bounded and traversed by lymphatic endothelial cells (LECs. A better understanding of LECs in human LNs is likely to improve our understanding of the regulation of cell trafficking within LNs, now an important therapeutic target, as well as disease processes that involve lymphatic sinuses. We therefore sought to map all the LECs within human LNs using multicolor immunofluorescence microscopy to visualize the distribution of a range of putative markers. PROX1 was the only marker that uniquely identified the LECs lining and traversing all the sinuses in human LNs. In contrast, LYVE1 and STAB2 were only expressed by LECs in the paracortical and medullary sinuses in the vast majority of LNs studied, whilst the subcapsular and trabecular sinuses lacked these molecules. These data highlight the existence of at least two distinctive populations of LECs within human LNs. Of the other LEC markers, we confirmed VEGFR3 was not specific for LECs, and CD144 and CD31 stained both LECs and blood vascular endothelial cells (BECs; in contrast, CD59 and CD105 stained BECs but not LECs. We also showed that antigen-presenting cells (APCs in the sinuses could be clearly distinguished from LECs by their expression of CD169, and their lack of expression of PROX1 and STAB2, or endothelial markers such as CD144. However, both LECs and sinus APCs were stained with DCN46, an antibody commonly used to detect CD209.

  14. 3-Bromopyruvate inhibits cell proliferation and induces apoptosis in CD133+ population in human glioma.

    Science.gov (United States)

    Xu, Dong-Qiang; Tan, Xiao-Yu; Zhang, Bao-Wei; Wu, Tao; Liu, Ping; Sun, Shao-Jun; Cao, Yin-Guang

    2016-03-01

    The study was aimed to investigate the role of 3-bromopyruvate in inhibition of CD133+ U87 human glioma cell population growth. The results demonstrated that 3-bromopyruvate inhibited the viability of both CD133+ and parental cells derived from U87 human glioma cell line. However, the 3-bromopyruvate-induced inhibition in viability was more prominent in CD133+ cells at 10 μM concentration after 48 h. Treatment of CD133+ cells with 3-bromopyruvate caused reduction in cell population and cell size, membrane bubbling, and degradation of cell membranes. Hoechst 33258 staining showed condensation of chromatin material and fragmentation of DNA in treated CD133+ cells after 48 h. 3-Bromopyruvate inhibited the migration rate of CD133+ cells significantly compared to the parental cells. Flow cytometry revealed that exposure of CD133+ cells to 3-bromopyruvate increased the cell population in S phase from 24.5 to 37.9 % with increase in time from 12 to 48 h. In addition, 3-bromopyruvate significantly enhanced the expression of Bax and cleaved caspase 3 in CD133+ cells compared to the parental cells. Therefore, 3-bromopyruvate is a potent chemotherapeutic agent for the treatment of glioma by targeting stem cells selectively.

  15. Detection and characterization of side population in Ewing's sarcoma SK-ES-1 cells in vitro

    International Nuclear Information System (INIS)

    Yang, Min; Zhang, Rui; Yan, Ming; Ye, Zhengxu; Liang, Wei; Luo, Zhuojing

    2010-01-01

    Dye exclusion is a valuable technique to isolate cancer stem cells (CSCs) based on an ability of stem cell to efflux fluorescent DNA-binding dye, especially for tumors without unique surface markers. It has been proven that side population (SP) cells that exclude Hoechst 33342 dye are enriched with stem-like cells in several cancer cell lines. In this study, we isolated and characterized SP cells from human Ewing's sarcoma cell line SK-ES-1 in vitro. SP cells were detected in SK-ES-1 and comprised 1.2% of total cell population. Only SP cells had the capacity to regenerate both SP and non-SP cells. The proliferation rates were similar between SP and non-SP cells. However, the clonogenicity and invasiveness of SP cells were significantly higher than that of non-SP cells. Further characterization of this SP phenotype presented other properties. SP cells exhibited increased multi-drug resistance and the ATP binding cassette protein (ABC) transporters were up-regulated in SP population. These findings suggest that SP cells derived from Ewing's sarcoma play the critical role in tumor metastasis and recurrence and might be an ideal target for clinical therapy.

  16. Evaluation of low red blood cell mean corpuscular volume in an apheresis donor population.

    Science.gov (United States)

    Bryant, Barbara J; Hopkins, Julie A; Arceo, Sarah M; Leitman, Susan F

    2009-09-01

    Apheresis donors are routinely evaluated with a complete blood count (CBC). Low red blood cell mean corpuscular volume (MCV) values (or=12.5 g/dL) could be due to iron deficiency or hemoglobinopathy. The etiology of a low MCV in a healthy apheresis donor population was assessed. Predonation samples for CBC were obtained from 1162 consecutive apheresis donors. Donors with a MCV of less than 80 fL were evaluated by CBC, iron studies (ferritin, serum iron, transferrin, percentage of transferrin saturation), and hemoglobin (Hb) electrophoresis. Iron deficiency was defined as a ferritin value below the reference range. Beta chain Hb variants were determined by Hb electrophoresis. Alpha thalassemia trait was presumed if the red blood cell (RBC) count was elevated, no variant Hbs were detected, and the iron studies were within normal ranges. In a 19-month period, 33 of 1162 apheresis donors had low MCV values. Iron deficiency was present in 64%; 49% had isolated iron deficiency and 15% had iron deficiency plus hemoglobinopathy. Hemoglobinopathy without concomitant iron deficiency was found in the remaining 36%. Iron deficiency is present in the majority of apheresis donors with repeatedly low MCV values and Hb levels of 12.5 g/dL or more. Hemoglobinopathy is also commonly present but may not be easily recognized in the setting of iron deficiency. The MCV is a useful screening tool to detect iron deficiency and hemoglobinopathy. Low MCV values should be investigated to determine if iron replacement therapy is indicated.

  17. A stem cell medium containing neural stimulating factor induces a pancreatic cancer stem-like cell-enriched population

    Science.gov (United States)

    WATANABE, YUSAKU; YOSHIMURA, KIYOSHI; YOSHIKAWA, KOICHI; TSUNEDOMI, RYOICHI; SHINDO, YOSHITARO; MATSUKUMA, SOU; MAEDA, NORIKO; KANEKIYO, SHINSUKE; SUZUKI, NOBUAKI; KURAMASU, ATSUO; SONODA, KOUHEI; TAMADA, KOJI; KOBAYASHI, SEI; SAYA, HIDEYUKI; HAZAMA, SHOICHI; OKA, MASAAKI

    2014-01-01

    Cancer stem cells (CSCs) have been studied for their self-renewal capacity and pluripotency, as well as their resistance to anticancer therapy and their ability to metastasize to distant organs. CSCs are difficult to study because their population is quite low in tumor specimens. To overcome this problem, we established a culture method to induce a pancreatic cancer stem-like cell (P-CSLC)-enriched population from human pancreatic cancer cell lines. Human pancreatic cancer cell lines established at our department were cultured in CSC-inducing media containing epidermal growth factor (EGF), basic fibroblast growth factor (bFGF), leukemia inhibitory factor (LIF), neural cell survivor factor-1 (NSF-1), and N-acetylcysteine. Sphere cells were obtained and then transferred to a laminin-coated dish and cultured for approximately two months. The surface markers, gene expression, aldehyde dehydrogenase (ALDH) activity, cell cycle, and tumorigenicity of these induced cells were examined for their stem cell-like characteristics. The population of these induced cells expanded within a few months. The ratio of CD24high, CD44high, epithelial specific antigen (ESA) high, and CD44variant (CD44v) high cells in the induced cells was greatly enriched. The induced cells stayed in the G0/G1 phase and demonstrated mesenchymal and stemness properties. The induced cells had high tumorigenic potential. Thus, we established a culture method to induce a P-CSLCenriched population from human pancreatic cancer cell lines. The CSLC population was enriched approximately 100-fold with this method. Our culture method may contribute to the precise analysis of CSCs and thus support the establishment of CSC-targeting therapy. PMID:25118635

  18. Analyses of 123 Peripheral Human Immune Cell Subsets: Defining Differences with Age and between Healthy Donors and Cancer Patients not Detected in Analysis of Standard Immune Cell Types

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    Lauren M. Lepone

    2016-03-01

    suppressor cells, conventional dendritic cells (DCs, plasmacytoid DCs and B cells. The use of these panels identifying 123 immune cell subsets may aid in the identi‐ fication of patients who may benefit from immunotherapy, either prior to therapy or early in the immunotherapeutic regimen, for the treatment of cancer or other chronic or infectious diseases.

  19. Imbalance of placental regulatory T cell and Th17 cell population dynamics in the FIV-infected pregnant cat

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    Boudreaux Crystal E

    2012-05-01

    Full Text Available Abstract Background An appropriate balance in placental regulatory T cells (Tregs, an immunosuppressive cell population, and Th17 cells, a pro-inflammatory cell population, is essential in allowing tolerance of the semi-allogeneic fetus. TGF-β and IL-6 are cytokines that promote differentiation of Tregs and Th17 cells from a common progenitor; aberrant expression of the cytokines may perturb the balance in the two cell populations. We previously reported a pro-inflammatory placental environment with decreased levels of FoxP3, a Treg marker, and increased levels of IL-6 in the placentas of FIV-infected cats at early pregnancy. Thus, we hypothesized that FIV infection in the pregnant cat causes altered placental Treg and Th17 cell populations, possibly resulting in placental inflammation. Methods We examined the effect of FIV infection on Treg and Th17 populations in placentas at early pregnancy using quantitative confocal microscopy to measure FoxP3 or RORγ, a Th17 marker, and qPCR to quantify expression of the key cytokines TGF-β and IL-6. Results FoxP3 and RORγ were positively correlated in FIV-infected placentas at early pregnancy, but not placentas from normal cats, indicating virus-induced alteration in the balance of these cell populations. In control cats the expression of IL-6 and RORγ was positively correlated as predicted, but this relationship was disrupted in infected animals. TGF-β was reduced in infected queens, an occurrence that could dysregulate both Treg and Th17 cell populations. Co-expression analyses revealed a highly significant positive correlation between IL-6 and TGF-β expression in control animals that did not occur in infected animals. Conclusion Collectively, these data point toward potential disruption in the balance of Treg and Th17 cell populations that may contribute to FIV-induced inflammation in the feline placenta.

  20. Single Cell Dynamics Causes Pareto-Like Effect in Stimulated T Cell Populations.

    Science.gov (United States)

    Cosette, Jérémie; Moussy, Alice; Onodi, Fanny; Auffret-Cariou, Adrien; Neildez-Nguyen, Thi My Anh; Paldi, Andras; Stockholm, Daniel

    2015-12-09

    Cell fate choice during the process of differentiation may obey to deterministic or stochastic rules. In order to discriminate between these two strategies we used time-lapse microscopy of individual murine CD4 + T cells that allows investigating the dynamics of proliferation and fate commitment. We observed highly heterogeneous division and death rates between individual clones resulting in a Pareto-like dominance of a few clones at the end of the experiment. Commitment to the Treg fate was monitored using the expression of a GFP reporter gene under the control of the endogenous Foxp3 promoter. All possible combinations of proliferation and differentiation were observed and resulted in exclusively GFP-, GFP+ or mixed phenotype clones of very different population sizes. We simulated the process of proliferation and differentiation using a simple mathematical model of stochastic decision-making based on the experimentally observed parameters. The simulations show that a stochastic scenario is fully compatible with the observed Pareto-like imbalance in the final population.

  1. Cellular morphometry and cycling cell populations of human and dog bronchi. Final report, April 1, 1988 - December 31, 1996

    International Nuclear Information System (INIS)

    Robbins, E.S.

    1996-12-01

    Quantitative data of the human bronchial epithelial cells at possible risk for malignant transformation in lung cancer is crucial for accurate radon dosimetry and risk analysis. The locations and other parameters of the nuclei which may be damaged by α particles and develop into cancers have been determined and compared in different airway generations, among smokers, non-smokers and ex-smokers, between men and women and in people of different ages. This research included extended morphometric studies on electron micrographs of human epithelium of defined airway generations. Since cycling cells can be more sensitive to damage from carcinogens and radioactivity, a second major part of this research consisted of studies to quantitate the cycling tracheobronchial epithelial population(s) using immunocytochemistry and the proliferation marker PCNA on paraffin sections. The basal and suprabasal cycling cell populations of the bronchi of smokers, non-smokers, and ex-smokers, men and women were compared. Normal human airway linings were also compared with normal adult dog trachea and bronchi as well as metaplastic and repairing human airways. The quantitative data from this project resulted in several publications on the cycling and putative stem cells of the tracheobronchial epithelium and more accurate radon dosimetry and risk analyses

  2. Defining Glaucomatous Optic Neuropathy from a Continuous Measure of Optic Nerve Damage - The Optimal Cut-off Point for Risk-factor Analysis in Population-based Epidemiology

    NARCIS (Netherlands)

    Ramdas, Wishal D.; Rizopoulos, Dimitris; Wolfs, Roger C. W.; Hofman, Albert; de Jong, Paulus T. V. M.; Vingerling, Johannes R.; Jansonius, Nomdo M.

    2011-01-01

    Purpose: Diseases characterized by a continuous trait can be defined by setting a cut-off point for the disease measure in question, accepting some misclassification. The 97.5th percentile is commonly used as a cut-off point. However, it is unclear whether this percentile is the optimal cut-off

  3. Competitor analogs for defined T cell antigens: peptides incorporating a putative binding motif and polyproline or polyglycine spacers.

    Science.gov (United States)

    Maryanski, J L; Verdini, A S; Weber, P C; Salemme, F R; Corradin, G

    1990-01-12

    We describe a new approach for modeling antigenic peptides recognized by T cells. Peptide A24 170-182 can compete with other antigenic peptides that are recognized by H-2kd-restricted cytolytic T cells, presumably by binding to the Kd molecule. By comparing substituted A24 peptides as competitors in a functional competition assay, the A24 residues Tyr-171, Thr-178, and Leu-179 were identified as possible contact residues for Kd. A highly active competitor peptide analog was synthesized in which Tyr was separated from the Thr-Leu pair by a pentaproline spacer. The choice of proline allowed the prediction of a probable conformation for the analog when bound to the Kd molecule. The simplest conformation of the A24 peptide that allows the same spacing and orientation of the motif as in the analog would be a nearly extended polypeptide chain incorporating a single 3(10) helical turn or similar structural kink.

  4. Derivation and characterization of the NIH registry human stem cell line NYSCF100 line under defined feeder-free conditions

    Directory of Open Access Journals (Sweden)

    Ana Sevilla

    2018-05-01

    Full Text Available The human embryonic stem cell line NYSCFe001-A was derived from a day 6 blastocyst in feeder-free and antibiotic free conditions. The blastocyst was voluntarily donated for research as surplus after in vitro fertilization treatment following informed consent. The NYSCFe001-A line, registered as NYSCF100 on the NIH registry, presents normal karyotype, is mycoplasma free, expresses all the pluripotency markers and has the potential to differentiate into all three germ layers in vitro.

  5. Defined MicroRNAs Induce Aspects of Maturation in Mouse and Human Embryonic-Stem-Cell-Derived Cardiomyocytes

    Directory of Open Access Journals (Sweden)

    Desy S. Lee

    2015-09-01

    Full Text Available Pluripotent-cell-derived cardiomyocytes have great potential for use in research and medicine, but limitations in their maturity currently constrain their usefulness. Here, we report a method for improving features of maturation in murine and human embryonic-stem-cell-derived cardiomyocytes (m/hESC-CMs. We found that coculturing m/hESC-CMs with endothelial cells improves their maturity and upregulates several microRNAs. Delivering four of these microRNAs, miR-125b-5p, miR-199a-5p, miR-221, and miR-222 (miR-combo, to m/hESC-CMs resulted in improved sarcomere alignment and calcium handling, a more negative resting membrane potential, and increased expression of cardiomyocyte maturation markers. Although this could not fully phenocopy all adult cardiomyocyte characteristics, these effects persisted for two months following delivery of miR-combo. A luciferase assay demonstrated that all four miRNAs target ErbB4, and siRNA knockdown of ErbB4 partially recapitulated the effects of miR-combo. In summary, a combination of miRNAs induced via endothelial coculture improved ESC-CM maturity, in part through suppression of ErbB4 signaling.

  6. Stepwise DNA Methylation Changes Are Linked to Escape from Defined Proliferation Barriers and Mammary Epithelial Cell Immortalization

    Energy Technology Data Exchange (ETDEWEB)

    Novak, Petr; Jensen, Taylor J.; Garbe, James C.; Stampfer, Martha R.; Futscher, Bernard W.

    2009-04-20

    The timing and progression of DNA methylation changes during carcinogenesis are not completely understood. To develop a timeline of aberrant DNA methylation events during malignant transformation, we analyzed genome-wide DNA methylation patterns in an isogenic human mammary epithelial cell (HMEC) culture model of transformation. To acquire immortality and malignancy, the cultured finite lifespan HMEC must overcome two distinct proliferation barriers. The first barrier, stasis, is mediated by the retinoblastoma protein and can be overcome by loss of p16(INK4A) expression. HMEC that escape stasis and continue to proliferate become genomically unstable before encountering a second more stringent proliferation barrier, telomere dysfunction due to telomere attrition. Rare cells that acquire telomerase expression may escape this barrier, become immortal, and develop further malignant properties. Our analysis of HMEC transitioning from finite lifespan to malignantly transformed showed that aberrant DNA methylation changes occur in a stepwise fashion early in the transformation process. The first aberrant DNA methylation step coincides with overcoming stasis, and results in few to hundreds of changes, depending on how stasis was overcome. A second step coincides with immortalization and results in hundreds of additional DNA methylation changes regardless of the immortalization pathway. A majority of these DNA methylation changes are also found in malignant breast cancer cells. These results show that large-scale epigenetic remodeling occurs in the earliest steps of mammary carcinogenesis, temporally links DNA methylation changes and overcoming cellular proliferation barriers, and provides a bank of potential epigenetic biomarkers that mayprove useful in breast cancer risk assessment.

  7. Tumor endothelial markers define novel subsets of cancer-specific circulating endothelial cells associated with antitumor efficacy

    Science.gov (United States)

    Mehran, Reza; Nilsson, Monique; Khajavi, Mehrdad; Du, Zhiqiang; Cascone, Tina; Wu, Hua Kang; Cortes, Andrea; Xu, Li; Zurita, Amado; Schier, Robert; Riedel, Bernhard; El-Zein, Randa; Heymach, John V.

    2014-01-01

    Circulating endothelial cells (CEC) are derived from multiple sources including bone marrow (circulating endothelial progenitors [CEP]) and established vasculature (mature CEC). Although CEC have shown promise as a biomarker for cancer patients, their utility has been limited in part by the lack of specificity for tumor vasculature and the different non-malignant causes that can impact CEC. Tumor endothelial markers (TEM) are antigens enriched in tumor vs non-malignant endothelia. We hypothesized that TEMs may be detectable on CEC and that these circulating TEM+ endothelial cells (CTEC) may be a more specific marker for cancer and tumor response than standard CEC. We found that tumor-bearing mice had a relative increase in numbers of circulating CTEC, specifically with increased levels of TEM7 and TEM8 expression. Following treatment with various vascular targeting agents, we observed a decrease in CTEC that correlated with the reductions in tumor growth. We extended these findings to human clinical samples and observed that CTEC were present in esophageal cancer and non-small cell lung cancer (NSCLC) patients (N=40) and their levels decreased after surgical resection. These results demonstrate that CTEC are detectable in preclinical cancer models and cancer patients. Further, they suggest that CTEC offer a novel cancer-associated marker that may be useful as a blood-based surrogate for assessing the presence of tumor vasculature and antiangiogenic drug activity. PMID:24626092

  8. Stem cell-like differentiation potentials of endometrial side population cells as revealed by a newly developed in vivo endometrial stem cell assay.

    Directory of Open Access Journals (Sweden)

    Kaoru Miyazaki

    Full Text Available Endometrial stem/progenitor cells contribute to the cyclical regeneration of human endometrium throughout a woman's reproductive life. Although the candidate cell populations have been extensively studied, no consensus exists regarding which endometrial population represents the stem/progenitor cell fraction in terms of in vivo stem cell activity. We have previously reported that human endometrial side population cells (ESP, but not endometrial main population cells (EMP, exhibit stem cell-like properties, including in vivo reconstitution of endometrium-like tissues when xenotransplanted into immunodeficient mice. The reconstitution efficiency, however, was low presumably because ESP cells alone could not provide a sufficient microenvironment (niche to support their stem cell activity. The objective of this study was to establish a novel in vivo endometrial stem cell assay employing cell tracking and tissue reconstitution systems and to examine the stem cell properties of ESP through use of this assay.ESP and EMP cells isolated from whole endometrial cells were infected with lentivirus to express tandem Tomato (TdTom, a red fluorescent protein. They were mixed with unlabeled whole endometrial cells and then transplanted under the kidney capsule of ovariectomized immunodeficient mice. These mice were treated with estradiol and progesterone for eight weeks and nephrectomized. All of the grafts reconstituted endometrium-like tissues under the kidney capsules. Immunofluorescence revealed that TdTom-positive cells were significantly more abundant in the glandular, stromal, and endothelial cells of the reconstituted endometrium in mice transplanted with TdTom-labeled ESP cells than those with TdTom-labeled EMP cells.We have established a novel in vivo endometrial stem cell assay in which multi-potential differentiation can be identified through cell tracking during in vivo endometrial tissue reconstitution. Using this assay, we demonstrated that ESP

  9. Defining Optimized Properties of Modified mRNA to Enhance Virus- and DNA- Independent Protein Expression in Adult Stem Cells and Fibroblasts

    Directory of Open Access Journals (Sweden)

    Frauke Hausburg

    2015-02-01

    Full Text Available Background: By far, most strategies for cell reprogramming and gene therapy are based on the introduction of DNA after viral delivery. To avoid the high risks accompanying these goals, non-viral and DNA-free delivery methods for various cell types are required. Methods: Relying on an initially established PCR-based protocol for convenient template DNA production, we synthesized five differently modified EGFP mRNA (mmRNA species, incorporating various degrees of 5-methylcytidine-5'-triphosphate (5mC and pseudouridine-5'-triphosphate (Ψ. We then investigated their effect on i protein expression efficiencies and ii cell viability for human mesenchymal stem cells (hMSCs and fibroblasts from different origins. Results: Our protocol allows highly efficient mmRNA production in vitro, enabling rapid and stable protein expression after cell transfection. However, our results also demonstrate that the terminally optimal modification needs to be defined in pilot experiments for each particular cell type. Transferring our approach to the conversion of fibroblasts into skeletal myoblasts using mmRNA encoding MyoD, we confirm the huge potential of mmRNA based protein expression for virus- and DNA-free reprogramming strategies. Conclusion: The achieved high protein expression levels combined with good cell viability not only in fibroblasts but also in hMSCs provides a promising option for mmRNA based modification of various cell types including slowly proliferating adult stem cells. Therefore, we are confident that our findings will substantially contribute to the improvement of efficient cell reprogramming and gene therapy approaches.

  10. Defining the ATM-mediated barrier to tumorigenesis in somatic mammary cells following ErbB2 activation.

    Science.gov (United States)

    Reddy, Jay P; Peddibhotla, Sirisha; Bu, Wen; Zhao, Jing; Haricharan, Svasti; Du, Yi-Chieh Nancy; Podsypanina, Katrina; Rosen, Jeffrey M; Donehower, Larry A; Li, Yi

    2010-02-23

    p53, apoptosis, and senescence are frequently activated in preneoplastic lesions and are barriers to progression to malignancy. These barriers have been suggested to result from an ATM-mediated DNA damage response (DDR), which may follow oncogene-induced hyperproliferation and ensuing DNA replication stress. To elucidate the currently untested role of DDR in breast cancer initiation, we examined the effect of oncogene expression in several murine models of breast cancer. We did not observe a detectable DDR in early hyperplastic lesions arising in transgenic mice expressing several different oncogenes. However, DDR signaling was strongly induced in preneoplastic lesions arising from individual mammary cells transduced in vivo by retroviruses expressing either PyMT or ErbB2. Thus, activation of an oncogene after normal tissue development causes a DDR. Furthermore, in this somatic ErbB2 tumor model, ATM, and thus DDR, is required for p53 stabilization, apoptosis, and senescence. In palpable tumors in this model, p53 stabilization and apoptosis are lost, but unexpectedly senescence remains in many tumor cells. Thus, this murine model fully recapitulates early DDR signaling; the eventual suppression of its endpoints in tumorigenesis provides compelling evidence that ErbB2-induced aberrant mammary cell proliferation leads to an ATM-mediated DDR that activates apoptosis and senescence, and at least the former must be overcome to progress to malignancy. This in vivo study also uncovers an unexpected effect of ErbB2 activation previously known for its prosurvival roles, and suggests that protection of the ATM-mediated DDR-p53 signaling pathway may be important in breast cancer prevention.

  11. Novel microchip-based tools facilitating live cell imaging and assessment of functional heterogeneity within NK cell populations

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    Elin eForslund

    2012-10-01

    Full Text Available Each individual has a heterogeneous pool of NK cells consisting of cells that may be specialized towards specific functional responses such as secretion of cytokines or killing of tumor cells. Many conventional methods are not fit to characterize heterogeneous populations as they measure the average response of all cells. Thus, there is a need for experimental platforms that provide single cell resolution. In addition, there are also transient and stochastic variations in functional responses at the single cell level, calling for methods that allow studies of many events over extended times. This paper presents a versatile microchip platform enabling long-term microscopic studies of individual NK cells interacting with target cells. Each microchip contains an array of microwells, optimized for medium or high-resolution time-lapse imaging of single or multiple NK and target cells, or for screening of thousands of isolated NK-target cell interactions. Individual NK cells confined with target cells in small microwells is a suitable setup for high-content screening and rapid assessment of heterogeneity within populations, while microwells of larger dimensions are appropriate for studies of NK cell migration and sequential interactions with multiple target cells. By combining the chip technology with ultrasonic manipulation, NK and target cells can be forced to interact and positioned with high spatial accuracy within individual microwells. This setup effectively and synchronously creates NK-target conjugates at hundreds of parallel positions in the microchip. Thus, this facilitates assessment of temporal aspects of NK-target cell interactions, e.g. conjugation, immune synapse formation and cytotoxic events. The microchip platform presented here can be used to effectively address questions related to fundamental functions of NK cells that can lead to better understanding of how the behavior of individual cells add up to give a functional response at

  12. Neoplastic and stromal cells contribute to an extracellular matrix gene expression profile defining a breast cancer subtype likely to progress.

    Directory of Open Access Journals (Sweden)

    Tiziana Triulzi

    Full Text Available We recently showed that differential expression of extracellular matrix (ECM genes delineates four subgroups of breast carcinomas (ECM1, -2, -3- and -4 with different clinical outcome. To further investigate the characteristics of ECM signature and its impact on tumor progression, we conducted unsupervised clustering analyses in 6 additional independent datasets of invasive breast tumors from different platforms for a total of 643 samples. Use of four different clustering algorithms identified ECM3 tumors as an independent group in all datasets tested. ECM3 showed a homogeneous gene pattern, consisting of 58 genes encoding 43 structural ECM proteins. From 26 to 41% of the cases were ECM3-enriched, and analysis of datasets relevant to gene expression in neoplastic or corresponding stromal cells showed that both stromal and breast carcinoma cells can coordinately express ECM3 genes. In in vitro experiments, β-estradiol induced ECM3 gene production in ER-positive breast carcinoma cell lines, whereas TGFβ induced upregulation of the genes leading to ECM3 gene classification, especially in ER-negative breast carcinoma cells and in fibroblasts. Multivariate analysis of distant metastasis-free survival in untreated breast tumor patients revealed a significant interaction between ECM3 and histological grade (p = 0.001. Cox models, estimated separately in grade I-II and grade III tumors, indicated a highly significant association between ECM3 and worse survival probability only in grade III tumors (HR = 3.0, 95% CI = 1.3-7.0, p = 0.0098. Gene Set Enrichment analysis of ECM3 compared to non-ECM3 tumors revealed significant enrichment of epithelial-mesenchymal transition (EMT genes in both grade I-II and grade III subsets of ECM3 tumors. Thus, ECM3 is a robust cluster that identifies breast carcinomas with EMT features but with accelerated metastatic potential only in the undifferentiated (grade III phenotype. These findings support the

  13. HOX and TALE signatures specify human stromal stem cell populations from different sources.

    Science.gov (United States)

    Picchi, Jacopo; Trombi, Luisa; Spugnesi, Laura; Barachini, Serena; Maroni, Giorgia; Brodano, Giovanni Barbanti; Boriani, Stefano; Valtieri, Mauro; Petrini, Mario; Magli, Maria Cristina

    2013-04-01

    Human stromal stem cell populations reside in different tissues and anatomical sites, however a critical question related to their efficient use in regenerative medicine is whether they exhibit equivalent biological properties. Here, we compared cellular and molecular characteristics of stromal stem cells derived from the bone marrow, at different body sites (iliac crest, sternum, and vertebrae) and other tissues (dental pulp and colon). In particular, we investigated whether homeobox genes of the HOX and TALE subfamilies might provide suitable markers to identify distinct stromal cell populations, as HOX proteins control cell positional identity and, together with their co-factors TALE, are involved in orchestrating differentiation of adult tissues. Our results show that stromal populations from different sources, although immunophenotypically similar, display distinct HOX and TALE signatures, as well as different growth and differentiation abilities. Stromal stem cells from different tissues are characterized by specific HOX profiles, differing in the number and type of active genes, as well as in their level of expression. Conversely, bone marrow-derived cell populations can be essentially distinguished for the expression levels of specific HOX members, strongly suggesting that quantitative differences in HOX activity may be crucial. Taken together, our data indicate that the HOX and TALE profiles provide positional, embryological and hierarchical identity of human stromal stem cells. Furthermore, our data suggest that cell populations derived from different body sites may not represent equivalent cell sources for cell-based therapeutical strategies for regeneration and repair of specific tissues. Copyright © 2012 Wiley Periodicals, Inc.

  14. Defined Conditions for the Isolation and Expansion of Basal Prostate Progenitor Cells of Mouse and Human Origin

    Directory of Open Access Journals (Sweden)

    Thomas Höfner

    2015-03-01

    Full Text Available Methods to isolate and culture primary prostate epithelial stem/progenitor cells (PESCs have proven difficult and ineffective. Here, we present a method to grow and expand both murine and human basal PESCs long term in serum- and feeder-free conditions. The method enriches for adherent mouse basal PESCs with a Lin−SCA-1+CD49f+TROP2high phenotype. Progesterone and sodium selenite are additionally required for the growth of human Lin−CD49f+TROP2high PESCs. The gene-expression profiles of expanded basal PESCs show similarities to ESCs, and NF-kB function is critical for epithelial differentiation of sphere-cultured PESCs. When transplanted in combination with urogenital sinus mesenchyme, expanded mouse and human PESCs generate ectopic prostatic tubules, demonstrating their stem cell activity in vivo. This novel method will facilitate the molecular, genomic, and functional characterization of normal and pathologic prostate glands of mouse and human origin.

  15. Analysing the Influence of the Spontaneous Aneuploidy Frequency on the Cell Population System Cultivation

    Directory of Open Access Journals (Sweden)

    G. A. Nefedov

    2015-01-01

    Full Text Available The paper provides a qualitative analysis of M.S. Vinogradova's nonlinear model for dynamics of the cell population system. This system describes the stem cells cultivation in vitro under resource constraints. The system consists of two populations, namely: population of normal cells and population of abnormal cells. Resource constraints are considered as linear dependences of mitosis parameters on the normalized densities of each population.One of the key parameters that effects on the realization of the system evolution scenarios is a parameter that determines a share of the normal cells, which pass, when dividing, into population of the abnormal cells. The paper analyses both the existence conditions of the rest points and the changes of the evolution scenarios of population system with changing abovementioned parameter and other system parameters held fixed. It is shown that there is a saddle-node bifurcation in the system; the bifurcation value of the parameter is found. The paper shows the interval of parameter values in which the favorable scenarios of population system evolution are implemented. It also presents results of mathematical modeling.

  16. Induction of Th1-Biased T Follicular Helper (Tfh) Cells in Lymphoid Tissues during Chronic Simian Immunodeficiency Virus Infection Defines Functionally Distinct Germinal Center Tfh Cells.

    Science.gov (United States)

    Velu, Vijayakumar; Mylvaganam, Geetha Hanna; Gangadhara, Sailaja; Hong, Jung Joo; Iyer, Smita S; Gumber, Sanjeev; Ibegbu, Chris C; Villinger, Francois; Amara, Rama Rao

    2016-09-01

    Chronic HIV infection is associated with accumulation of germinal center (GC) T follicular helper (Tfh) cells in the lymphoid tissue. The GC Tfh cells can be heterogeneous based on the expression of chemokine receptors associated with T helper lineages, such as CXCR3 (Th1), CCR4 (Th2), and CCR6 (Th17). However, the heterogeneous nature of GC Tfh cells in the lymphoid tissue and its association with viral persistence and Ab production during chronic SIV/HIV infection are not known. To address this, we characterized the expression of CXCR3, CCR4, and CCR6 on GC Tfh cells in lymph nodes following SIVmac251 infection in rhesus macaques. In SIV-naive rhesus macaques, only a small fraction of GC Tfh cells expressed CXCR3, CCR4, and CCR6. However, during chronic SIV infection, the majority of GC Tfh cells expressed CXCR3, whereas the proportion of CCR4(+) cells did not change, and CCR6(+) cells decreased. CXCR3(+), but not CXCR3(-), GC Tfh cells produced IFN-γ (Th1 cytokine) and IL-21 (Tfh cytokine), whereas both subsets expressed CD40L following stimulation. Immunohistochemistry analysis demonstrated an accumulation of CD4(+)IFN-γ(+) T cells within the hyperplastic follicles during chronic SIV infection. CXCR3(+) GC Tfh cells also expressed higher levels of ICOS, CCR5, and α4β7 and contained more copies of SIV DNA compared with CXCR3(-) GC Tfh cells. However, CXCR3(+) and CXCR3(-) GC Tfh cells delivered help to B cells in vitro for production of IgG. These data demonstrate that chronic SIV infection promotes expansion of Th1-biased GC Tfh cells, which are phenotypically and functionally distinct from conventional GC Tfh cells and contribute to hypergammaglobulinemia and viral reservoirs. Copyright © 2016 by The American Association of Immunologists, Inc.

  17. Late post-irradiation phenomena in mammalain cell populations. Pt. 2. Intraclonal recovery in sublines isolated from X-irradiated L5178Y-S cell populations

    International Nuclear Information System (INIS)

    Beer, J.Z.

    1975-01-01

    Clonal analysis of L5178Y-S cell populations irradiated with 300 rads of X-rays indicates occurence of cell sublines with considerably prolonged mean doubling times up to 22 h as compared to 10-11 h for control. Subsequent observations of growth of the handicapped sublines derived from single cells showed capability of all more than 100 studied sublines to recover normal proliferative activity. This process of intraclonal recovery required in many cases longer periods of time, corresponding to many tens, sometimes more than 200, generations. Late intraclonal recovery was further analysed by subcloning. It was found that although cytochemically assayed viability of the handicapped sublines was normal, cloning efficiency strongly depended on the stage of the recovery process. The recovery processes occuring in clones isolated from irradiated cell populations were compared with analogous processes occuring in slowly growing sublines isolated from non-irradiated cell cultures. Marked differences in kinetics of these processes show that either they are different in sublines derived from irradiated and non-irradiated cell populations or that the mechanisms of the late intraclonal recovery are affected by radiation. The results presented allow to conclude that gradual post-irradiation recovery of growth depends primarily on formation, in the developing populations, of cells with higher proliferative activities. Possible nature of the recovery processes is discussed in the light of available information on mammalian somatic cell variants with altered drug or temperature sensitivity, or with nutritional requirements. A sequence is proposed of changes leading from radiation-induced disturbance of the normably existing equilibrium between three basic cell subpopulations to ultimate restoration of this equilibrium. (author)

  18. Topological defects in confined populations of spindle-shaped cells

    Science.gov (United States)

    Duclos, Guillaume; Erlenkämper, Christoph; Joanny, Jean-François; Silberzan, Pascal

    2017-01-01

    Most spindle-shaped cells (including smooth muscles and sarcomas) organize in vivo into well-aligned `nematic’ domains, creating intrinsic topological defects that may be used to probe the behaviour of these active nematic systems. Active non-cellular nematics have been shown to be dominated by activity, yielding complex chaotic flows. However, the regime in which live spindle-shaped cells operate, and the importance of cell-substrate friction in particular, remains largely unexplored. Using in vitro experiments, we show that these active cellular nematics operate in a regime in which activity is effectively damped by friction, and that the interaction between defects is controlled by the system’s elastic nematic energy. Due to the activity of the cells, these defects behave as self-propelled particles and pairwise annihilate until all displacements freeze as cell crowding increases. When confined in mesoscopic circular domains, the system evolves towards two identical +1/2 disclinations facing each other. The most likely reduced positions of these defects are independent of the size of the disk, the cells’ activity or even the cell type, but are well described by equilibrium liquid crystal theory. These cell-based systems thus operate in a regime more stable than other active nematics, which may be necessary for their biological function.

  19. Carrier population control and surface passivation in solar cells

    KAUST Repository

    Cuevas, Andres; Wan, Yimao; Yan, Di; Samundsett, Christian; Allen, Thomas; Zhang, Xinyu; Cui, Jie; Bullock, James

    2018-01-01

    Controlling the concentration of charge carriers near the surface is essential for solar cells. It permits to form regions with selective conductivity for either electrons or holes and it also helps to reduce the rate at which they recombine

  20. small cell lung cancer in a Chinese population

    African Journals Online (AJOL)

    clinical significance in patients with non-small cell lung cancer (NSCLC) in Hubei province ... diagnosis, tumor stage, treatment, progression .... Table 4: Association between EGFR mutation, gender and histologic type in 138 NSCLC patients.

  1. Merging Mixture Components for Cell Population Identification in Flow Cytometry

    Directory of Open Access Journals (Sweden)

    Greg Finak

    2009-01-01

    Full Text Available We present a framework for the identification of cell subpopulations in flow cytometry data based on merging mixture components using the flowClust methodology. We show that the cluster merging algorithm under our framework improves model fit and provides a better estimate of the number of distinct cell subpopulations than either Gaussian mixture models or flowClust, especially for complicated flow cytometry data distributions. Our framework allows the automated selection of the number of distinct cell subpopulations and we are able to identify cases where the algorithm fails, thus making it suitable for application in a high throughput FCM analysis pipeline. Furthermore, we demonstrate a method for summarizing complex merged cell subpopulations in a simple manner that integrates with the existing flowClust framework and enables downstream data analysis. We demonstrate the performance of our framework on simulated and real FCM data. The software is available in the flowMerge package through the Bioconductor project.

  2. Analysis of Vaginal Cell Populations during Experimental Vaginal Candidiasis

    OpenAIRE

    Fidel, Paul L.; Luo, Wei; Steele, Chad; Chabain, Joseph; Baker, Marc; Wormley, Floyd

    1999-01-01

    Studies with an estrogen-dependent murine model of vaginal candidiasis suggest that local cell-mediated immunity (CMI) is more important than systemic CMI for protection against vaginitis. The present study, however, showed that, compared to uninfected mice, little to no change in the percentage or types of vaginal T cells occurred during a primary vaginal infection or during a secondary vaginal infection where partial protection was observed. Furthermore, depletion of polymorphonuclear leuko...

  3. The Phenotype of Circulating Follicular-Helper T Cells in Patients with Rheumatoid Arthritis Defines CD200 as a Potential Therapeutic Target

    Directory of Open Access Journals (Sweden)

    Aron Chakera

    2012-01-01

    Full Text Available Rheumatoid arthritis (RA is a systemic autoimmune disease primarily affecting synovial joints in which the development of autoantibodies represents a failure of normal tolerance mechanisms, suggesting a role for follicular helper T cells (TFH in the genesis of autoimmunity. To determine whether quantitative or qualitative abnormalities in the circulating TFH cell population exist, we analysed by flow cytometry the number and profile of these cells in 35 patients with RA and 15 matched controls. Results were correlated with patient characteristics, including the presence of autoantibodies, disease activity, and treatment with biologic agents. Circulating TFH cells from patients with RA show significantly increased expression of the immunoglobulin superfamily receptor CD200, with highest levels seen in seropositive patients (P=0.0045 and patients treated with anti-TNFα agents (P=0.0008. This occurs in the absence of any change in TFH numbers or overt bias towards Th1, Th2, or Th17 phenotypes. CD200 levels did not correlate with DAS28 scores (P=0.887. Although the number of circulating TFH cells is not altered in the blood of patients with RA, the TFH cells have a distinct phenotype. These differences associate TFH cells with the pathogenesis of RA and support the relevance of the CD200/CD200R signalling pathway as a potential therapeutic target.

  4. A novel chemical-defined medium with bFGF and N2B27 supplements supports undifferentiated growth in human embryonic stem cells

    International Nuclear Information System (INIS)

    Liu Yanxia; Song Zhihua; Zhao Yang; Qin Han; Cai Jun; Zhang Hong; Yu Tianxin; Jiang Siming; Wang Guangwen; Ding Mingxiao; Deng Hongkui

    2006-01-01

    Traditionally, undifferentiated human embryonic stem cells (hESCs) are maintained on mouse embryonic fibroblast (MEF) cells or on matrigel with an MEF-conditioned medium (CM), which hampers the clinical applications of hESCs due to the contamination by animal pathogens. Here we report a novel chemical-defined medium using DMEM/F12 supplemented with N2, B27, and basic fibroblast growth factor (bFGF) [termed NBF]. This medium can support prolonged self-renewal of hESCs. hESCs cultured in NBF maintain an undifferentiated state and normal karyotype, are able to form embryoid bodies in vitro, and differentiate into three germ layers and extraembryonic cells. Furthermore, we find that hESCs cultured in NBF possess a low apoptosis rate and a high proliferation rate compared with those cultured in MEF-CM. Our findings provide a novel, simplified chemical-defined culture medium suitable for further therapeutic applications and developmental studies of hESCs

  5. Defining a target population at high risk of long-term foster care: barriers to permanency for families of children with serious emotional disturbances.

    Science.gov (United States)

    Akin, Becci A; Bryson, Stephanie A; McDonald, Tom; Walker, Sheila

    2012-01-01

    Long-term foster care (LTFC) is an enduring problem that lacks evidence of effective strategies for practice or policy. This article describes initial activities of a statewide project of the national Permanency Innovations Initiative. The authors sought to: (1) verify the relevance of children's mental health as a predictor of LTFC, (2) describe critical barriers encountered by parents of children with serious emotional disturbances, and (3) identify systems barriers that hinder permanency for this target population.

  6. Endometrial Stromal Cells and Immune Cell Populations Within Lymph Nodes in a Nonhuman Primate Model of Endometriosis

    Science.gov (United States)

    Fazleabas, A. T.; Braundmeier, A. G.; Markham, R.; Fraser, I. S.; Berbic, M.

    2011-01-01

    Mounting evidence suggests that immunological responses may be altered in endometriosis. The baboon (Papio anubis) is generally considered the best model of endometriosis pathogenesis. The objective of the current study was to investigate for the first time immunological changes within uterine and peritoneal draining lymph nodes in a nonhuman primate baboon model of endometriosis. Paraffin-embedded femoral lymph nodes were obtained from 22 normally cycling female baboons (induced endometriosis n = 11; control n = 11). Immunohistochemical staining was performed with antibodies for endometrial stromal cells, T cells, immature and mature dendritic cells, and B cells. Lymph nodes were evaluated using an automated cellular imaging system. Endometrial stromal cells were significantly increased in lymph nodes from animals with induced endometriosis, compared to control animals (P = .033). In animals with induced endometriosis, some lymph node immune cell populations including T cells, dendritic cells and B cells were increased, suggesting an efficient early response or peritoneal drainage. PMID:21617251

  7. Analysis of Vaginal Cell Populations during Experimental Vaginal Candidiasis

    Science.gov (United States)

    Fidel, Paul L.; Luo, Wei; Steele, Chad; Chabain, Joseph; Baker, Marc; Wormley, Floyd

    1999-01-01

    Studies with an estrogen-dependent murine model of vaginal candidiasis suggest that local cell-mediated immunity (CMI) is more important than systemic CMI for protection against vaginitis. The present study, however, showed that, compared to uninfected mice, little to no change in the percentage or types of vaginal T cells occurred during a primary vaginal infection or during a secondary vaginal infection where partial protection was observed. Furthermore, depletion of polymorphonuclear leukocytes (PMN) had no effect on infection in the presence or absence of pseudoestrus. These results indicate a lack of demonstrable effects by systemic CMI or PMN against vaginitis and suggest that if local T cells are important, they are functioning without showing significant increases in numbers within the vaginal mucosa during infection. PMID:10338532

  8. Chondrogenic Differentiation of Defined Equine Mesenchymal Stem Cells Derived from Umbilical Cord Blood for Use in Cartilage Repair Therapy

    Directory of Open Access Journals (Sweden)

    Mélanie Desancé

    2018-02-01

    Full Text Available Cartilage engineering is a new strategy for the treatment of cartilage damage due to osteoarthritis or trauma in humans. Racehorses are exposed to the same type of cartilage damage and the anatomical, cellular, and biochemical properties of their cartilage are comparable to those of human cartilage, making the horse an excellent model for the development of cartilage engineering. Human mesenchymal stem cells (MSCs differentiated into chondrocytes with chondrogenic factors in a biomaterial appears to be a promising therapeutic approach for direct implantation and cartilage repair. Here, we characterized equine umbilical cord blood-derived MSCs (eUCB-MSCs and evaluated their potential for chondrocyte differentiation for use in cartilage repair therapy. Our results show that isolated eUCB-MSCs had high proliferative capacity and differentiated easily into osteoblasts and chondrocytes, but not into adipocytes. A three-dimensional (3D culture approach with the chondrogenic factors BMP-2 and TGF-β1 potentiated chondrogenic differentiation with a significant increase in cartilage-specific markers at the mRNA level (Col2a1, Acan, Snorc and the protein level (type II and IIB collagen without an increase in hypertrophic chondrocyte markers (Col10a1 and Mmp13 in normoxia and in hypoxia. However, these chondrogenic factors caused an increase in type I collagen, which can be reduced using small interfering RNA targeting Col1a2. This study provides robust data on MSCs characterization and demonstrates that eUCB-MSCs have a great potential for cartilage tissue engineering.

  9. Sox2, Tlx, Gli3, and Her9 converge on Rx2 to define retinal stem cells in vivo

    Science.gov (United States)

    Reinhardt, Robert; Centanin, Lázaro; Tavhelidse, Tinatini; Inoue, Daigo; Wittbrodt, Beate; Concordet, Jean-Paul; Martinez-Morales, Juan Ramón; Wittbrodt, Joachim

    2015-01-01

    Transcriptional networks defining stemness in adult neural stem cells (NSCs) are largely unknown. We used the proximal cis-regulatory element (pCRE) of the retina-specific homeobox gene 2 (rx2) to address such a network. Lineage analysis in the fish retina identified rx2 as marker for multipotent NSCs. rx2-positive cells located in the peripheral ciliary marginal zone behave as stem cells for the neuroretina, or the retinal pigmented epithelium. We identified upstream regulators of rx2 interrogating the rx2 pCRE in a trans-regulation screen and focused on four TFs (Sox2, Tlx, Gli3, and Her9) activating or repressing rx2 expression. We demonstrated direct interaction of the rx2 pCRE with the four factors in vitro and in vivo. By conditional mosaic gain- and loss-of-function analyses, we validated the activity of those factors on regulating rx2 transcription and consequently modulating neuroretinal and RPE stem cell features. This becomes obvious by the rx2-mutant phenotypes that together with the data presented above identify rx2 as a transcriptional hub balancing stemness of neuroretinal and RPE stem cells in the adult fish retina. PMID:25908840

  10. Cellular population dynamics control the robustness of the stem cell niche

    Directory of Open Access Journals (Sweden)

    Adam L. MacLean

    2015-11-01

    Full Text Available Within populations of cells, fate decisions are controlled by an indeterminate combination of cell-intrinsic and cell-extrinsic factors. In the case of stem cells, the stem cell niche is believed to maintain ‘stemness’ through communication and interactions between the stem cells and one or more other cell-types that contribute to the niche conditions. To investigate the robustness of cell fate decisions in the stem cell hierarchy and the role that the niche plays, we introduce simple mathematical models of stem and progenitor cells, their progeny and their interplay in the niche. These models capture the fundamental processes of proliferation and differentiation and allow us to consider alternative possibilities regarding how niche-mediated signalling feedback regulates the niche dynamics. Generalised stability analysis of these stem cell niche systems enables us to describe the stability properties of each model. We find that although the number of feasible states depends on the model, their probabilities of stability in general do not: stem cell–niche models are stable across a wide range of parameters. We demonstrate that niche-mediated feedback increases the number of stable steady states, and show how distinct cell states have distinct branching characteristics. The ecological feedback and interactions mediated by the stem cell niche thus lend (surprisingly high levels of robustness to the stem and progenitor cell population dynamics. Furthermore, cell–cell interactions are sufficient for populations of stem cells and their progeny to achieve stability and maintain homeostasis. We show that the robustness of the niche – and hence of the stem cell pool in the niche – depends only weakly, if at all, on the complexity of the niche make-up: simple as well as complicated niche systems are capable of supporting robust and stable stem cell dynamics.

  11. In vitro expansion of the mammary stem/progenitor cell population by xanthosine treatment

    Directory of Open Access Journals (Sweden)

    Choudhary Ratan K

    2012-06-01

    Full Text Available Abstract Background Mammary stem cells are critical for growth and maintenance of the mammary gland and therefore are of considerable interest for improving productivity and efficiency of dairy animals. Xanthosine treatment has been demonstrated to promote expansion of putative mammary stem cells in vivo, and hepatic and hair follicle stem cells in vitro. In the latter, xanthosine promoted the symmetrical division of hepatic and hair follicle stem cells. The objective of this study was to determine if treating primary cultures of bovine mammary epithelial cells (MEC with xanthosine increases the stem/progenitor cell population by promoting symmetrical division of mammary stem cells. Results In vitro treatment with xanthosine increased the population of MEC during the exponential phase of cell growth, reducing the doubling time from 86 h in control cultures to 60 h in xanthosine-treated cultures. The bromodeoxyuridine (BrdU labeling index and the proportion of MEC in S-phase both were increased by xanthosine treatment, indicating that increased cell accretion was due to increased cell proliferation. Analysis of daughter-pairs indicated that xanthosine promoted a shift from asymmetric to symmetric cell division. Moreover, the 30 % increase in symmetric cell division was concomitant with an increase in the proportion of MEC that were positive for a putative stem cell marker (FNDC3B and a trend toward increased telomerase activity. These results suggest that xanthosine treatment in vitro can increase cell proliferation, promote symmetric cell division and enhance stem/progenitor cell activity. Conclusions Xanthosine treatment increased the proliferation rate of bovine MEC in vitro. This was likely to be mediated by an increase in the proportion of stem/progenitor cells in the MEC population due to promotion of symmetrical stem cell division by xanthosine.

  12. Diffuse Large B-Cell Lymphoma in the Elderly: Real World Outcomes of Immunochemotherapy in Asian Population.

    Science.gov (United States)

    Byun, Ja Min; Lee, Jeong-Ok; Kang, Beodeul; Kim, Ji-Won; Kim, Se Hyun; Kim, Jin Won; Kim, Yu Jung; Lee, Keun-Wook; Bang, Soo-Mee; Lee, Jong Seok

    2016-09-01

    We evaluated the real-life treatment outcomes of elderly patients with diffuse large B-cell lymphoma from a homogenous Asian population and defined the cutoff age for "elderly." The medical records of 192 DLBCL patients aged > 60 years who had received first-line immunochemotherapy were retrospectively evaluated. The treatment schedule, adverse events, and survival outcomes were analyzed overall and stratified by 4 age groups (> 60-64, 65-69, 70-74, and ≥ 75 years). Patient age of ≥ 75 years was associated with a significantly lower complete remission rate (86.5% vs. 81.4% vs. 82.0% vs. 51%; P population, 75 years seems to be a judicious cutoff for predicting treatment outcomes. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Prognostic value of defining the systemic tumor volume with FDG-PET in diffuse large b cell lymphoma

    International Nuclear Information System (INIS)

    Byun, Byung Hyun; Lim, Sang Moo; Cheon, Gi Jeong; Choi, Chang Woon; Kang, Hye Jin; Na, Im Il; Ryoo, Baek Yeol; Yang, Sung Hyun

    2007-01-01

    We measured the systemic tumor volume using FDG-PET in patients with diffuse large B cell lymphoma (DLBL). We also investigated its prognostic role, and compared it with that of other prognostic factors. FDG PET was performed in 38 newly diagnosed DLBL patients (20 men, 18 women, age 55.715.1 years) at pre-treatment of chemotherapy. Clinical staging of lymphoma was evaluated by Ann Arbor system. On each FDG PET scan, we acquired volume of interest (VOl) at the cut-off value of SUV=2.5 in every measurable tumor by the automatic edge detection software. According to the VOI, we measured the metabolic volume and mean SUV, and estimated volume-activity indexes (SUV Vol) as mean SUV times metabolic volume. And then, we calculated the summed metabolic volume (VOLsum) and summed SUV Vol (SUV Volsum) in every FDG PET scan. Maximum SUV of involved lesion (SUVmax) was also acquired on each FDG PET scan. Time to treatment failure (TTF) was compared among VOLsum (median), SUV Volsum (median), SUVmax (median), clinical stage, gender, age, LDH, and performance status-assigned response designations by Kaplan-Meier survival analysis. Initial stages of DLBL patients were stage I in 4, II in 14, III in 15, and IV in 4 by Ann Arbor system. Median follow up period was 15.5months, and estimated mean TTF was 22.3 months. Univariate analysis demonstrated that TTF is statistically significantly reduced in those with high VOLsum (>215.1cm2, p=0.004), high SUV Volsum (>1577.5, p=0.003), and increased LDH (p=0.036). TTF did not correlate with SUVmax (p=0.571), clinical stage (p=0.194), gender (p=0.549), and age (p=0.128), and performance status =2 (p=0.074). Multivariate analysis using VOLsum, SUV Volsum, LDH, and performance status demonstrated no statistically significant predictor of TTF (p>0.05). Systemic tumor volume measurement using FDG-PET is suggestive to be the significant prognostic factor in patients with DLBL

  14. Association between intake of less-healthy foods defined by the United Kingdom's nutrient profile model and cardiovascular disease: A population-based cohort study.

    Directory of Open Access Journals (Sweden)

    Oliver T Mytton

    2018-01-01

    Full Text Available In the United Kingdom, the Food Standards Agency-Ofcom nutrient profiling model (FSA-Ofcom model is used to define less-healthy foods that cannot be advertised to children. However, there has been limited investigation of whether less-healthy foods defined by this model are associated with prospective health outcomes. The objective of this study was to test whether consumption of less-healthy food as defined by the FSA-Ofcom model is associated with cardiovascular disease (CVD.We used data from the European Prospective Investigation of Cancer (EPIC-Norfolk cohort study in adults (n = 25,639 aged 40-79 years who completed a 7-day diet diary between 1993 and 1997. Incident CVD (primary outcome, cardiovascular mortality, and all-cause mortality (secondary outcomes were identified using record linkage to hospital admissions data and death certificates up to 31 March 2015. Each food and beverage item reported was coded and given a continuous score, using the FSA-Ofcom model, based on the consumption of energy; saturated fat; total sugar; sodium; nonsoluble fibre; protein; and fruits, vegetables, and nuts. Items were classified as less-healthy using Ofcom regulation thresholds. We used Cox proportional hazards regression to test for an association between consumption of less-healthy food and incident CVD. Sensitivity analyses explored whether the results differed based on the definition of the exposure. Analyses were adjusted for age, sex, behavioural risk factors, clinical risk factors, and socioeconomic status. Participants were followed up for a mean of 16.4 years. During follow-up, there were 4,965 incident cases of CVD (1,524 fatal within 30 days. In the unadjusted analyses, we observed an association between consumption of less-healthy food and incident CVD (test for linear trend over quintile groups, p < 0.01. After adjustment for covariates (sociodemographic, behavioural, and indices of cardiovascular risk, we found no association between

  15. Synchronization of glycolytic oscillations in a yeast cell population

    DEFF Research Database (Denmark)

    Dano, S.; Hynne, F.; De Monte, Silvia

    2001-01-01

    The mechanism of active phase synchronization in a suspension of oscillatory yeast cells has remained a puzzle for almost half a century. The difficulty of the problem stems from the fact that the synchronization phenomenon involves the entire metabolic network of glycolysis and fermentation, and...

  16. 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.

  17. 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

    Directory of Open Access Journals (Sweden)

    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

  18. Wnt signaling positively regulates endothelial cell fate specification in the Fli1a-positive progenitor population via Lef1.

    Science.gov (United States)

    Hübner, Kathleen; Grassme, Kathrin S; Rao, Jyoti; Wenke, Nina K; Zimmer, Cordula L; Korte, Laura; Mu Ller, Katja; Sumanas, Saulius; Greber, Boris; Herzog, Wiebke

    2017-10-01

    During vertebrate embryogenesis, vascular endothelial cells (ECs) and primitive erythrocytes become specified within close proximity in the posterior lateral plate mesoderm (LPM) from a common progenitor. However, the signaling cascades regulating the specification into either lineage remain largely elusive. Here, we analyze the contribution of β-catenin dependent Wnt signaling to EC and erythrocyte specification during zebrafish embryogenesis. We generated novel β-catenin dependent Wnt signaling reporters which, by using destabilized fluorophores (Venus-Pest, dGFP), specifically allow us to detect Wnt signaling responses in narrow time windows as well as in spatially restricted domains, defined by Cre recombinase expression (Tg(axin2 BAC :Venus-Pest) mu288 ; Tg(14TCF:loxP-STOP-loxP-dGFP) mu202 ). We therefore can detect β-catenin dependent Wnt signaling activity in a subset of the Fli1a-positive progenitor population. Additionally, we show that mesodermal Wnt3a-mediated signaling via the transcription factor Lef1 positively regulates EC specification (defined by kdrl expression) at the expense of primitive erythrocyte specification (defined by gata1 expression) in zebrafish embryos. Using mesoderm derived from human embryonic stem cells, we identified the same principle of Wnt signaling dependent EC specification in conjunction with auto-upregulation of LEF1. Our data indicate a novel role of β-catenin dependent Wnt signaling in regulating EC specification during vasculogenesis. Copyright © 2017. Published by Elsevier Inc.

  19. Identification and clonal characterisation of a progenitor cell sub-population in normal human articular cartilage.

    Directory of Open Access Journals (Sweden)

    Rebecca Williams

    Full Text Available BACKGROUND: Articular cartilage displays a poor repair capacity. The aim of cell-based therapies for cartilage defects is to repair damaged joint surfaces with a functional replacement tissue. Currently, chondrocytes removed from a healthy region of the cartilage are used but they are unable to retain their phenotype in expanded culture. The resulting repair tissue is fibrocartilaginous rather than hyaline, potentially compromising long-term repair. Mesenchymal stem cells, particularly bone marrow stromal cells (BMSC, are of interest for cartilage repair due to their inherent replicative potential. However, chondrocyte differentiated BMSCs display an endochondral phenotype, that is, can terminally differentiate and form a calcified matrix, leading to failure in long-term defect repair. Here, we investigate the isolation and characterisation of a human cartilage progenitor population that is resident within permanent adult articular cartilage. METHODS AND FINDINGS: Human articular cartilage samples were digested and clonal populations isolated using a differential adhesion assay to fibronectin. Clonal cell lines were expanded in growth media to high population doublings and karyotype analysis performed. We present data to show that this cell population demonstrates a restricted differential potential during chondrogenic induction in a 3D pellet culture system. Furthermore, evidence of high telomerase activity and maintenance of telomere length, characteristic of a mesenchymal stem cell population, were observed in this clonal cell population. Lastly, as proof of principle, we carried out a pilot repair study in a goat in vivo model demonstrating the ability of goat cartilage progenitors to form a cartilage-like repair tissue in a chondral defect. CONCLUSIONS: In conclusion, we propose that we have identified and characterised a novel cartilage progenitor population resident in human articular cartilage which will greatly benefit future cell

  20. The use of real-time cell analyzer technology in drug discovery: defining optimal cell culture conditions and assay reproducibility with different adherent cellular models.

    Science.gov (United States)

    Atienzar, Franck A; Tilmant, Karen; Gerets, Helga H; Toussaint, Gaelle; Speeckaert, Sebastien; Hanon, Etienne; Depelchin, Olympe; Dhalluin, Stephane

    2011-07-01

    The use of impedance-based label-free technology applied to drug discovery is nowadays receiving more and more attention. Indeed, such a simple and noninvasive assay that interferes minimally with cell morphology and function allows one to perform kinetic measurements and to obtain information on proliferation, migration, cytotoxicity, and receptor-mediated signaling. The objective of the study was to further assess the usefulness of a real-time cell analyzer (RTCA) platform based on impedance in the context of quality control and data reproducibility. The data indicate that this technology is useful to determine the best coating and cellular density conditions for different adherent cellular models including hepatocytes, cardiomyocytes, fibroblasts, and hybrid neuroblastoma/neuronal cells. Based on 31 independent experiments, the reproducibility of cell index data generated from HepG2 cells exposed to DMSO and to Triton X-100 was satisfactory, with a coefficient of variation close to 10%. Cell index data were also well reproduced when cardiomyocytes and fibroblasts were exposed to 21 compounds three times (correlation >0.91, p technology appears to be a powerful and reliable tool in drug discovery because of the reasonable throughput, rapid and efficient performance, technical optimization, and cell quality control.

  1. Reduced satellite cell population may lead to contractures in children with cerebral palsy.

    Science.gov (United States)

    Smith, Lucas R; Chambers, Henry G; Lieber, Richard L

    2013-03-01

    Satellite cells are the stem cells residing in muscle responsible for skeletal muscle growth and repair. Skeletal muscle in cerebral palsy (CP) has impaired longitudinal growth that results in muscle contractures. We hypothesized that the satellite cell population would be reduced in contractured muscle. We compared the satellite cell populations in hamstring muscles from participants with CP contracture (n=8; six males, two females; age range 6-15y; Gross Motor Function Classification System [GMFCS] levels II-V; 4 with hemiplegia, 4 with diplegia) and from typically developing participants (n=8; six males, two females, age range 15-18y). Muscle biopsies were extracted from the gracilis and semitendinosus muscles and mononuclear cells were isolated. Cell surface markers were stained with fluorescently conjugated antibodies to label satellite cells (neural cell adhesion molecule) and inflammatory and endothelial cells (CD34 and CD4 respectively). Cells were analyzed using flow cytometry to determine cell populations. After gating for intact cells a mean of 12.8% (SD 2.8%) were determined to be satellite cells in typically developing children, but only 5.3% (SD 2.3%; p0.05) suggesting the isolation procedure was valid. A reduced satellite cell population may account for the decreased longitudinal growth of muscles in CP that develop into fixed contractures or the decreased ability to strengthen muscle in CP. This suggests a unique musculoskeletal disease mechanism and provides a potential therapeutic target for debilitating muscle contractures. © The Authors. Developmental Medicine & Child Neurology © 2012 Mac Keith Press.

  2. The prevalence of EGFR mutations in non-small cell lung cancer in an unselected Caucasian population

    DEFF Research Database (Denmark)

    Skov, Birgit G; Høgdall, Estrid; Clementsen, Paul

    2015-01-01

    in a well-defined Danish population were included. The type of the diagnostic material, and data on smoking were registered. The mutation analyses were investigated by Therascreen EGFR RGQ-PCR Kit or Sanger sequencing. A total of 658 men and 598 women were included. 6.2% were never smokers, 38.9% were ex-smokers.......0% of adenocarcinomas, and 1.9% of squamous cell carcinomas were mutated. 29.4%, 4.4% and 2.9% of never, ex- and current smokers were mutated (p ... EGFR mutation. Adenocarcinomas were mutated more often (8.0%) than squamous cell carcinomas (1.9%). Mutations were found in never smokers as well as in former and current smokers. No difference in gender and age regarding mutation status was observed. EGFR mutations analysis was possible in almost all...

  3. Mechanism of derivation of radioresistance in HeLa cell population after repeated x-irradiation

    International Nuclear Information System (INIS)

    Kubo, Kihei; Koiwai, Soichiro; Morita, Kazuo

    1982-01-01

    The Radioresistant strain (X-8-5) was obtained from HeLa-SC population X-irradiated repeatedly for five times with 800 rad. The mean lethal dose (D 0 ) was 196 rad for X-8-5 cells, while it was 166 rad for control HeLa-SC cells. The fraction of cells containing an unusually long acrocentric chromosome (LA 2) exclusively increased with increasing number of irradiation of HeLa-SC population. A clonal strain with LA 2 marker was isolated from X-8-5 population and named RC-355. Since the RC-355 cells were more resistant (D 0 = 220 rad)than parental X-8-5 cells (D 0 = 196 rad), it was suggested that the cells with LA 2 were responsible for the radioresistance of X-8-5 population. The RC-355 cells were further subjected to the analysis of Q-banded karyotypes and it was observed that 18 types of specific markers (rm 1-17 and LA 2) were included in RC-355 cells in addition to 12 types of markers observed in most of HeLa-SC cells. Since the analysis of Q-banded karyotypes of RC-355 cells showed that RC-355 specific markers were not produced by radiation-induced rearrangements of HeLa-SC chromosomes, because twelve kinds of HeLa-SC markers were presented in RC-355 cells without any change, it was concluded that a small number of cells with LA 2 marker were originally presented in the control population and the relative fraction of them occupied increased after irradiation. (author)

  4. Repeated cisplatin treatment can lead to a multiresistant tumor cell population with stem cell features and sensitivity to 3-bromopyruvate.

    Science.gov (United States)

    Wintzell, My; Löfstedt, Lina; Johansson, Joel; Pedersen, Anne B; Fuxe, Jonas; Shoshan, Maria

    2012-12-01

    Cisplatin is used in treatment of several types of cancer, including epithelial ovarian carcinoma (EOC). In order to mimic clinical treatment and to investigate longterm effects of cisplatin in surviving cancer cells, two EOC cell lines were repeatedly treated with low doses. In the SKOV-3 cell line originating from malignant ascites, but not in A2780 cells from a primary tumor, this led to emergence of a stable population (SKOV-3-R) which in the absence of cisplatin showed increased motility, epithelial-mesenchymal transition (EMT) and expression of cancer stem cell markers CD117, CD44 and ALDH1. Accordingly, the cells formed self-renewing spheres in serum-free stem cell medium. Despite upregulation of mitochondrial mass and cytochrome c, and no upregulation of Bcl-2/Bcl-xL, SKOV-3-R were multiresistant to antineoplastic drugs. Cancer stem cells, or tumor-initiating cells (TICs) are highly chemoresistant and are believed to cause relapse into disseminated and resistant EOC. Our second aim was therefore to target resistance in these TIC-like cells. Resistance could be correlated with upregulation of hexokinase-II and VDAC, which are known to form a survival-promoting mitochondrial complex. The cells were thus sensitive to 3-bromopyruvate, which dissociates hexokinase-II from this complex, and were particularly sensitive to combination treatment with cisplatin at doses down to 0.1 x IC 50. 3-bromopyruvate might thus be of use in targeting the especially aggressive TIC populations.

  5. Generational distribution of a Candida glabrata population: Resilient old cells prevail, while younger cells dominate in the vulnerable host.

    Science.gov (United States)

    Bouklas, Tejas; Alonso-Crisóstomo, Luz; Székely, Tamás; Diago-Navarro, Elizabeth; Orner, Erika P; Smith, Kalie; Munshi, Mansa A; Del Poeta, Maurizio; Balázsi, Gábor; Fries, Bettina C

    2017-05-01

    Similar to other yeasts, the human pathogen Candida glabrata ages when it undergoes asymmetric, finite cell divisions, which determines its replicative lifespan. We sought to investigate if and how aging changes resilience of C. glabrata populations in the host environment. Our data demonstrate that old C. glabrata are more resistant to hydrogen peroxide and neutrophil killing, whereas young cells adhere better to epithelial cell layers. Consequently, virulence of old compared to younger C. glabrata cells is enhanced in the Galleria mellonella infection model. Electron microscopy images of old C. glabrata cells indicate a marked increase in cell wall thickness. Comparison of transcriptomes of old and young C. glabrata cells reveals differential regulation of ergosterol and Hog pathway associated genes as well as adhesion proteins, and suggests that aging is accompanied by remodeling of the fungal cell wall. Biochemical analysis supports this conclusion as older cells exhibit a qualitatively different lipid composition, leading to the observed increased emergence of fluconazole resistance when grown in the presence of fluconazole selection pressure. Older C. glabrata cells accumulate during murine and human infection, which is statistically unlikely without very strong selection. Therefore, we tested the hypothesis that neutrophils constitute the predominant selection pressure in vivo. When we altered experimentally the selection pressure by antibody-mediated removal of neutrophils, we observed a significantly younger pathogen population in mice. Mathematical modeling confirmed that differential selection of older cells is sufficient to cause the observed demographic shift in the fungal population. Hence our data support the concept that pathogenesis is affected by the generational age distribution of the infecting C. glabrata population in a host. We conclude that replicative aging constitutes an emerging trait, which is selected by the host and may even play an

  6. Importance of characteristics and modalities of physical activity and exercise in defining the benefits to cardiovascular health within the general population: recommendations from the EACPR (Part I).

    Science.gov (United States)

    Vanhees, L; De Sutter, J; GeladaS, N; Doyle, F; Prescott, E; Cornelissen, V; Kouidi, E; Dugmore, D; Vanuzzo, D; Börjesson, M; Doherty, P

    2012-08-01

    Over the last decades, more and more evidence is accumulated that physical activity (PA) and exercise interventions are essential components in primary and secondary prevention for cardiovascular disease. However, it is less clear whether and which type of PA and exercise intervention (aerobic exercise, dynamic resistive exercise, or both) or characteristic of exercise (frequency, intensity, time or duration, and volume) would yield more benefit in achieving cardiovascular health. The present paper, as the first of a series of three, will make specific recommendations on the importance of these characteristics for cardiovascular health in the population at large. The guidance offered in this series of papers is aimed at medical doctors, health practitioners, kinesiologists, physiotherapists and exercise physiologists, politicians, public health policy makers, and the individual member of the public. Based on previous and the current literature, recommendations from the European Association on Cardiovascular Prevention and Rehabilitation are formulated regarding type, volume, and intensity of PA and exercise.

  7. Shaping bacterial population behavior through computer-interfaced control of individual cells.

    Science.gov (United States)

    Chait, Remy; Ruess, Jakob; Bergmiller, Tobias; Tkačik, Gašper; Guet, Călin C

    2017-11-16

    Bacteria in groups vary individually, and interact with other bacteria and the environment to produce population-level patterns of gene expression. Investigating such behavior in detail requires measuring and controlling populations at the single-cell level alongside precisely specified interactions and environmental characteristics. Here we present an automated, programmable platform that combines image-based gene expression and growth measurements with on-line optogenetic expression control for hundreds of individual Escherichia coli cells over days, in a dynamically adjustable environment. This integrated platform broadly enables experiments that bridge individual and population behaviors. We demonstrate: (i) population structuring by independent closed-loop control of gene expression in many individual cells, (ii) cell-cell variation control during antibiotic perturbation, (iii) hybrid bio-digital circuits in single cells, and freely specifiable digital communication between individual bacteria. These examples showcase the potential for real-time integration of theoretical models with measurement and control of many individual cells to investigate and engineer microbial population behavior.

  8. HFE gene polymorphism defined by sequence-based typing of the Brazilian population and a standardized nomenclature for HFE allele sequences.

    Science.gov (United States)

    Campos, W N; Massaro, J D; Martinelli, A L C; Halliwell, J A; Marsh, S G E; Mendes-Junior, C T; Donadi, E A

    2017-10-01

    The HFE molecule controls iron uptake from gut, and defects in the molecule have been associated with iron overload, particularly in hereditary hemochromatosis. The HFE gene including both coding and boundary intronic regions were sequenced in 304 Brazilian individuals, encompassing healthy individuals and patients exhibiting hereditary or acquired iron overload. Six sites of variation were detected: (1) H63D C>G in exon 2, (2) IVS2 (+4) T>C in intron 2, (3) a C>G transversion in intron 3, (4) C282Y G>A in exon 4, (5) IVS4 (-44) T>C in intron 4, and (6) a new guanine deletion (G>del) in intron 5, which were used for haplotype inference. Nine HFE alleles were detected and six of these were officially named on the basis of the HLA Nomenclature, defined by the World Health Organization (WHO) Nomenclature Committee for Factors of the HLA System, and published via the IPD-IMGT/HLA website. Four alleles, HFE*001, *002, *003, and *004 exhibited variation within their exon sequences. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  9. Defined xenogeneic-free and hypoxic environment provides superior conditions for long-term expansion of human adipose-derived stem cells.

    Science.gov (United States)

    Yang, Sufang; Pilgaard, Linda; Chase, Lucas G; Boucher, Shayne; Vemuri, Mohan C; Fink, Trine; Zachar, Vladimir

    2012-08-01

    Development and implementation of therapeutic protocols based on stem cells or tissue-engineered products relies on methods that enable the production of substantial numbers of cells while complying with stringent quality and safety demands. In the current study, we aimed to assess the benefits of maintaining cultures of adipose-derived stem cells (ASCs) in a defined culture system devoid of xenogeneic components (xeno-free) and hypoxia over a 49-day growth period. Our data provide evidence that conditions involving StemPro mesenchymal stem cells serum-free medium (SFM) Xeno-Free and hypoxia (5% oxygen concentration) in the culture atmosphere provide a superior proliferation rate compared to a standard growth environment comprised of alpha-modified Eagle medium (A-MEM) supplemented with fetal calf serum (FCS) and ambient air (20% oxygen concentration) or that of A-MEM supplemented with FCS and hypoxia. Furthermore, a flow cytometric analysis and in vitro differentiation assays confirmed the immunophenotype stability and maintained multipotency of ASCs when expanded under xeno-free conditions and hypoxia. In conclusion, our data demonstrate that growth conditions utilizing a xeno-free and hypoxic environment not only provide an improved environment for the expansion of ASCs, but also set the stage as a culture system with the potential broad spectrum utility for regenerative medicine and tissue engineering applications.

  10. Modelling the collective response of heterogeneous cell populations to stationary gradients and chemical signal relay

    Science.gov (United States)

    Pineda, M.; Eftimie, R.

    2017-12-01

    The directed motion of cell aggregates toward a chemical source occurs in many relevant biological processes. Understanding the mechanisms that control this complex behavior is of great relevance for our understanding of developmental biological processes and many diseases. In this paper, we consider a self-propelled particle model for the movement of heterogeneous subpopulations of chemically interacting cells towards an imposed stable chemical gradient. Our simulations show explicitly how self-organisation of cell populations (which could lead to engulfment or complete cell segregation) can arise from the heterogeneity of chemotactic responses alone. This new result complements current theoretical and experimental studies that emphasise the role of differential cell-cell adhesion on self-organisation and spatial structure of cellular aggregates. We also investigate how the speed of individual cell aggregations increases with the chemotactic sensitivity of the cells, and decreases with the number of cells inside the aggregates

  11. An efficient and reproducible process for transmission electron microscopy (TEM) of rare cell populations

    Science.gov (United States)

    Kumar, Sachin; Ciraolo, Georgianne; Hinge, Ashwini; Filippi, Marie-Dominique

    2014-01-01

    Transmission electron microscopy (TEM) provides ultra-structural details of cells at the sub-organelle level. However, details of the cellular ultrastructure, and the cellular organization and content of various organelles in rare populations, particularly in the suspension, like hematopoietic stem cells (HSCs) remained elusive. This is mainly due to the requirement of millions of cells for TEM studies. Thus, there is a vital requirement of a method that will allow TEM studies with low cell numbers of such rare populations. We describe an alternative and novel approach for TEM studies for rare cell populations. Here we performed TEM study from 10,000 HSC cells with quite ease. In particular, tiny cell pellets were identified by Evans blue staining after PFA-GA fixation. The cell pellet was pre-embedded in agarose in a small microcentrifuge tube and processed for dehydration, infiltration and embedding. Semi-thin and ultra-thin sections identified clusters of numerous cells per sections with well preserved morphology and ultrastructural details of golgi complex and mitochondria. Together, this method provides an efficient, easy and reproducible process to perform qualitative and quantitative TEM analysis from limited biological samples including cells in suspension. PMID:24291346

  12. 75 FR 54351 - Cell and Gene Therapy Clinical Trials in Pediatric Populations; Public Workshop

    Science.gov (United States)

    2010-09-07

    ...] Cell and Gene Therapy Clinical Trials in Pediatric Populations; Public Workshop AGENCY: Food and Drug... Biologics Evaluation and Research (CBER) is announcing a public workshop entitled ``Cell and Gene Therapy... Institutional Review Boards (IRBs), gene and cellular therapy clinical researchers, and other stakeholders...

  13. Calcium Imaging Reveals Coordinated Simple Spike Pauses in Populations of Cerebellar Purkinje Cells

    Directory of Open Access Journals (Sweden)

    Jorge E. Ramirez

    2016-12-01

    Full Text Available The brain’s control of movement is thought to involve coordinated activity between cerebellar Purkinje cells. The results reported here demonstrate that somatic Ca2+ imaging is a faithful reporter of Na+-dependent “simple spike” pauses and enables us to optically record changes in firing rates in populations of Purkinje cells in brain slices and in vivo. This simultaneous calcium imaging of populations of Purkinje cells reveals a striking spatial organization of pauses in Purkinje cell activity between neighboring cells. The source of this organization is shown to be the presynaptic gamma-Aminobutyric acid producing (GABAergic network, and blocking ionotropic gamma-Aminobutyric acid receptor (GABAARs abolishes the synchrony. These data suggest that presynaptic interneurons synchronize (inactivity between neighboring Purkinje cells, and thereby maximize their effect on downstream targets in the deep cerebellar nuclei.

  14. Defining Prolonged Length of Acute Care Stay for Surgically and Conservatively Treated Patients with Spontaneous Intracerebral Hemorrhage: A Population-Based Analysis

    Directory of Open Access Journals (Sweden)

    Marco Stein

    2016-01-01

    Full Text Available Background. The definition of prolonged length of stay (LOS during acute care remains unclear among surgically and conservatively treated patients with intracerebral hemorrhage (ICH. Methods. Using a population-based quality assessment registry, we calculated change points in LOS for surgically and conservatively treated patients with ICH. The influence of comorbidities, baseline characteristics at admission, and in-hospital complications on prolonged LOS was evaluated in a multivariate model. Results. Overall, 13272 patients with ICH were included in the analysis. Surgical therapy of the hematoma was documented in 1405 (10.6% patients. Change points for LOS were 22 days (CI: 8, 22; CL 98% for surgically treated patients and 16 days (CI: 16, 16; CL: 99% for conservatively treated patients. Ventilation therapy was related to prolonged LOS in surgically (OR: 2.2, 95% CI: 1.5–3.1; P<0.001 and conservatively treated patients (OR: 2.5, 95% CI: 2.2–2.9; P<0.001. Two or more in-hospital complications in surgical patients (OR: 2.7, 95% CI: 2.1–3.5 and ≥1 in conservative patients (OR: 3.0, 95% CI: 2.7–3.3 were predictors of prolonged LOS. Conclusion. The definition of prolonged LOS after ICH could be useful for several aspects of quality management and research. Preventing in-hospital complications could decrease the number of patients with prolonged LOS.

  15. Mining of hospital laboratory information systems: a model study defining age- and gender-specific reference intervals and trajectories for plasma creatinine in a pediatric population.

    Science.gov (United States)

    Søeby, Karen; Jensen, Peter Bjødstrup; Werge, Thomas; Sørensen, Steen

    2015-09-01

    The knowledge of physiological fluctuation and variation of even commonly used biochemical quantities in extreme age groups and during development is sparse. This challenges the clinical interpretation and utility of laboratory tests in these age groups. To explore the utility of hospital laboratory data as a source of information, we analyzed enzymatic plasma creatinine as a model analyte in two large pediatric hospital samples. Plasma creatinine measurements from 9700 children aged 0-18 years were obtained from hospital laboratory databases and partitioned into high-resolution gender- and age-groups. Normal probability plots were used to deduce parameters of the normal distributions from healthy creatinine values in the mixed hospital datasets. Furthermore, temporal trajectories were generated from repeated measurements to examine developmental patterns in periods of changing creatinine levels. Creatinine shows great age dependence from birth throughout childhood. We computed and replicated 95% reference intervals in narrow gender and age bins and showed them to be comparable to those determined in healthy population studies. We identified pronounced transitions in creatinine levels at different time points after birth and around the early teens, which challenges the establishment and usefulness of reference intervals in those age groups. The study documents that hospital laboratory data may inform on the developmental aspects of creatinine, on periods with pronounced heterogeneity and valid reference intervals. Furthermore, part of the heterogeneity in creatinine distribution is likely due to differences in biological and chronological age of children and should be considered when using age-specific reference intervals.

  16. Reconstructing human pancreatic differentiation by mapping specific cell populations during development

    DEFF Research Database (Denmark)

    Ramond, Cyrille; Glaser, Nicolas; Berthault, Claire

    2017-01-01

    . Endocrine maturation progresses by up-regulating SUSD2 and lowering ECAD levels. Finally, in vitro differentiation of pancreatic endocrine cells derived from human pluripotent stem cells mimics key in vivo events. Our work paves the way to extend our understanding of the origin of mature human pancreatic......Information remains scarce on human development compared to animal models. Here, we reconstructed human fetal pancreatic differentiation using cell surface markers. We demonstrate that at 7weeks of development, the glycoprotein 2 (GP2) marks a multipotent cell population that will differentiate...... cell types and how such lineage decisions are regulated....

  17. The epidermis comprises autonomous compartments maintained by distinct stem cell populations

    DEFF Research Database (Denmark)

    Page, Mahalia E; Lombard, Patrick; Ng, Felicia

    2013-01-01

    populations. In contrast, upon wounding, stem cell progeny from multiple compartments acquire lineage plasticity and make permanent contributions to regenerating tissue. We further show that oncogene activation in Lrig1(+ve) cells drives hyperplasia but requires auxiliary stimuli for tumor formation....... In summary, our data demonstrate that epidermal stem cells are lineage restricted during homeostasis and suggest that compartmentalization may constitute a conserved mechanism underlying epithelial tissue maintenance....

  18. Crypt cell population kinetics in mouse jejunum under continuous beta irradiation from tritiated water

    International Nuclear Information System (INIS)

    Bhatia, A.L.; Gupta, M.L.; Saharan, B.R.

    1979-01-01

    The behaviour of crypt cell population in mouse jejunum under continuous beta irradiation from tritiated water (HTO) has been studied. Adult mice were maintained on tritiated drinking water of the activity of 1.25 μCi/ml, after priming injection. The crypts were studied at 1, 5, 7, 15 and 30 days after the initiation of treatment. It is observed that there is a partial recovery in proliferative activity after the first day of the treatment. Again there is a decrease in the crypt cells on the 7th day, after which this population appears to achieve a near-steady-state level at about 8% below normal at the last interval studied. Crypt cell population and mitotic figures showed a simultaneous dip and recovery, while dead cells showed inverse relationship. (orig.) [de

  19. Single-cell systems level analysis of human Toll-Like-Receptor activation defines a chemokine signature in Systemic Lupus Erythematosus

    Science.gov (United States)

    O'Gorman, William E.; Hsieh, Elena W.Y.; Savig, Erica S.; Gherardini, Pier Federico; Hernandez, Joseph D.; Hansmann, Leo; Balboni, Imelda M.; Utz, Paul J.; Bendall, Sean C.; Fantl, Wendy J.; Lewis, David B.; Nolan, Garry P.; Davis, Mark M.

    2015-01-01

    Background Activation of Toll-Like Receptors (TLRs) induces inflammatory responses involved in immunity to pathogens and autoimmune pathogenesis, such as in Systemic Lupus Erythematosus (SLE). Although TLRs are differentially expressed across the immune system, a comprehensive analysis of how multiple immune cell subsets respond in a system-wide manner has previously not been described. Objective To characterize TLR activation across multiple immune cell subsets and individuals, with the goal of establishing a reference framework against which to compare pathological processes. Methods Peripheral whole blood samples were stimulated with TLR ligands, and analyzed by mass cytometry simultaneously for surface marker expression, activation states of intracellular signaling proteins, and cytokine production. We developed a novel data visualization tool to provide an integrated view of TLR signaling networks with single-cell resolution. We studied seventeen healthy volunteer donors and eight newly diagnosed untreated SLE patients. Results Our data revealed the diversity of TLR-induced responses within cell types, with TLR ligand specificity. Subsets of NK and T cells selectively induced NF-κB in response to TLR2 ligands. CD14hi monocytes exhibited the most polyfunctional cytokine expression patterns, with over 80 distinct cytokine combinations. Monocytic TLR-induced cytokine patterns were shared amongst a group of healthy donors, with minimal intra- and inter- individual variability. Furthermore, autoimmune disease altered baseline cytokine production, as newly diagnosed untreated SLE patients shared a distinct monocytic chemokine signature, despite clinical heterogeneity. Conclusion Mass cytometry analysis defined a systems-level reference framework for human TLR activation, which can be applied to study perturbations in inflammatory disease, such as SLE. PMID:26037552

  20. Cellular morphometry and cycling cell populations of human and dog bronchi. Annual progress report, April 1, 1994--March 31, 1995

    Energy Technology Data Exchange (ETDEWEB)

    Robbins, E.S.

    1994-12-01

    Quantitative data of the human bronchial epithelial cells at possible risk for malignant transformation in lung cancer is crucial for accurate radon dosimetry and risk analysis. The nuclei of these cells may be targets for damage by {alpha} particles. Then it is important to determine the locations and other parameters of these nuclei in different airway generations, among smokers, non-smokers and ex-smokers, between men and women and in people of different ages. This proposal includes extended morphometric studies on electron micrographs of human bronchial epithelium of defined airway generations. The second part of this proposal describes the continuation of studies to quantitate the cycling tracheo-bronchial epithelial population(s) using proliferation markers and immunocytochemistry on paraffin sections. The proliferative potential of the airway mucosa of smokers, non-smokers, and ex-smokers, men and women, as well as individuals of different ages are being compared. Normal human bronchial linings are also being compared with normal adult dog bronchi and metaplastic and repairing human airways. Since cycling cells can be more sensitive to damage from carcinogens and radioactivity, the quantitative data from this project will allow the development of more accurate radon risk analysis.

  1. Cellular morphometry and cycling cell populations of human and dog bronchi. Annual progress report, April 1, 1994--March 31, 1995

    International Nuclear Information System (INIS)

    Robbins, E.S.

    1994-12-01

    Quantitative data of the human bronchial epithelial cells at possible risk for malignant transformation in lung cancer is crucial for accurate radon dosimetry and risk analysis. The nuclei of these cells may be targets for damage by α particles. Then it is important to determine the locations and other parameters of these nuclei in different airway generations, among smokers, non-smokers and ex-smokers, between men and women and in people of different ages. This proposal includes extended morphometric studies on electron micrographs of human bronchial epithelium of defined airway generations. The second part of this proposal describes the continuation of studies to quantitate the cycling tracheo-bronchial epithelial population(s) using proliferation markers and immunocytochemistry on paraffin sections. The proliferative potential of the airway mucosa of smokers, non-smokers, and ex-smokers, men and women, as well as individuals of different ages are being compared. Normal human bronchial linings are also being compared with normal adult dog bronchi and metaplastic and repairing human airways. Since cycling cells can be more sensitive to damage from carcinogens and radioactivity, the quantitative data from this project will allow the development of more accurate radon risk analysis

  2. Effects of defined mixtures of persistent organic pollutants (POPs) on multiple cellular responses in the human hepatocarcinoma cell line, HepG2, using high content analysis screening

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Jodie [Institute for Global Food Security, School of Biological Sciences, Queen' s University Belfast, Northern Ireland (United Kingdom); Berntsen, Hanne Friis; Zimmer, Karin Elisabeth [Norwegian University of Life Sciences, Oslo (Norway); Frizzell, Caroline [Institute for Global Food Security, School of Biological Sciences, Queen' s University Belfast, Northern Ireland (United Kingdom); Verhaegen, Steven; Ropstad, Erik [Norwegian University of Life Sciences, Oslo (Norway); Connolly, Lisa, E-mail: l.connolly@qub.ac.uk [Institute for Global Food Security, School of Biological Sciences, Queen' s University Belfast, Northern Ireland (United Kingdom)

    2016-03-01

    Persistent organic pollutants (POPs) are toxic substances, highly resistant to environmental degradation, which can bio-accumulate and have long-range atmospheric transport potential. Most studies focus on single compound effects, however as humans are exposed to several POPs simultaneously, investigating exposure effects of real life POP mixtures on human health is necessary. A defined mixture of POPs was used, where the compound concentration reflected its contribution to the levels seen in Scandinavian human serum (total mix). Several sub mixtures representing different classes of POPs were also constructed. The perfluorinated (PFC) mixture contained six perfluorinated compounds, brominated (Br) mixture contained seven brominated compounds, chlorinated (Cl) mixture contained polychlorinated biphenyls and also p,p’-dichlorodiphenyldichloroethylene, hexachlorobenzene, three chlordanes, three hexachlorocyclohexanes and dieldrin. Human hepatocarcinoma (HepG2) cells were used for 2 h and 48 h exposures to the seven mixtures and analysis on a CellInsight™ NXT High Content Screening platform. Multiple cytotoxic endpoints were investigated: cell number, nuclear intensity and area, mitochondrial mass and membrane potential (MMP) and reactive oxygen species (ROS). Both the Br and Cl mixtures induced ROS production but did not lead to apoptosis. The PFC mixture induced ROS production and likely induced cell apoptosis accompanied by the dissipation of MMP. Synergistic effects were evident for ROS induction when cells were exposed to the PFC + Br mixture in comparison to the effects of the individual mixtures. No significant effects were detected in the Br + Cl, PFC + Cl or total mixtures, which contain the same concentrations of chlorinated compounds as the Cl mixture plus additional compounds; highlighting the need for further exploration of POP mixtures in risk assessment. - Highlights: • High content analysis (HCA) is a novel approach for determining toxicity of

  3. Effects of defined mixtures of persistent organic pollutants (POPs) on multiple cellular responses in the human hepatocarcinoma cell line, HepG2, using high content analysis screening

    International Nuclear Information System (INIS)

    Wilson, Jodie; Berntsen, Hanne Friis; Zimmer, Karin Elisabeth; Frizzell, Caroline; Verhaegen, Steven; Ropstad, Erik; Connolly, Lisa

    2016-01-01

    Persistent organic pollutants (POPs) are toxic substances, highly resistant to environmental degradation, which can bio-accumulate and have long-range atmospheric transport potential. Most studies focus on single compound effects, however as humans are exposed to several POPs simultaneously, investigating exposure effects of real life POP mixtures on human health is necessary. A defined mixture of POPs was used, where the compound concentration reflected its contribution to the levels seen in Scandinavian human serum (total mix). Several sub mixtures representing different classes of POPs were also constructed. The perfluorinated (PFC) mixture contained six perfluorinated compounds, brominated (Br) mixture contained seven brominated compounds, chlorinated (Cl) mixture contained polychlorinated biphenyls and also p,p’-dichlorodiphenyldichloroethylene, hexachlorobenzene, three chlordanes, three hexachlorocyclohexanes and dieldrin. Human hepatocarcinoma (HepG2) cells were used for 2 h and 48 h exposures to the seven mixtures and analysis on a CellInsight™ NXT High Content Screening platform. Multiple cytotoxic endpoints were investigated: cell number, nuclear intensity and area, mitochondrial mass and membrane potential (MMP) and reactive oxygen species (ROS). Both the Br and Cl mixtures induced ROS production but did not lead to apoptosis. The PFC mixture induced ROS production and likely induced cell apoptosis accompanied by the dissipation of MMP. Synergistic effects were evident for ROS induction when cells were exposed to the PFC + Br mixture in comparison to the effects of the individual mixtures. No significant effects were detected in the Br + Cl, PFC + Cl or total mixtures, which contain the same concentrations of chlorinated compounds as the Cl mixture plus additional compounds; highlighting the need for further exploration of POP mixtures in risk assessment. - Highlights: • High content analysis (HCA) is a novel approach for determining toxicity of

  4. Adaptation of a Commonly Used, Chemically Defined Medium for Human Embryonic Stem Cells to Stable Isotope Labeling with Amino Acids in Cell Culture

    DEFF Research Database (Denmark)

    Liberski, A. R.; Al-Noubi, M. N.; Rahman, Z. H.

    2013-01-01

    Metabolic labeling with stable isotopes is a prominent technique for comparative quantitative proteomics, and stable isotope labeling with amino acids in cell culture (SILAC) is the most commonly used approach. SILAC is, however, traditionally limited to simple tissue culture regimens and only ra...

  5. CSF1R+ Macrophages Sustain Pancreatic Tumor Growth through T Cell Suppression and Maintenance of Key Gene Programs that Define the Squamous Subtype.

    Science.gov (United States)

    Candido, Juliana B; Morton, Jennifer P; Bailey, Peter; Campbell, Andrew D; Karim, Saadia A; Jamieson, Thomas; Lapienyte, Laura; Gopinathan, Aarthi; Clark, William; McGhee, Ewan J; Wang, Jun; Escorcio-Correia, Monica; Zollinger, Raphael; Roshani, Rozita; Drew, Lisa; Rishi, Loveena; Arkell, Rebecca; Evans, T R Jeffry; Nixon, Colin; Jodrell, Duncan I; Wilkinson, Robert W; Biankin, Andrew V; Barry, Simon T; Balkwill, Frances R; Sansom, Owen J

    2018-05-01

    Pancreatic ductal adenocarcinoma (PDAC) is resistant to most therapies including single-agent immunotherapy and has a dense desmoplastic stroma, and most patients present with advanced metastatic disease. We reveal that macrophages are the dominant leukocyte population both in human PDAC stroma and autochthonous models, with an important functional contribution to the squamous subtype of human PDAC. We targeted macrophages in a genetic PDAC model using AZD7507, a potent selective inhibitor of CSF1R. AZD7507 caused shrinkage of established tumors and increased mouse survival in this difficult-to-treat model. Malignant cell proliferation diminished, with increased cell death and an enhanced T cell immune response. Loss of macrophages rewired other features of the TME, with global changes in gene expression akin to switching PDAC subtypes. These changes were markedly different to those elicited when neutrophils were targeted via CXCR2. These results suggest targeting the myeloid cell axis may be particularly efficacious in PDAC, especially with CSF1R inhibitors. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

  6. DAFi: A directed recursive data filtering and clustering approach for improving and interpreting data clustering identification of cell populations from polychromatic flow cytometry data.

    Science.gov (United States)

    Lee, Alexandra J; Chang, Ivan; Burel, Julie G; Lindestam Arlehamn, Cecilia S; Mandava, Aishwarya; Weiskopf, Daniela; Peters, Bjoern; Sette, Alessandro; Scheuermann, Richard H; Qian, Yu

    2018-04-17

    Computational methods for identification of cell populations from polychromatic flow cytometry data are changing the paradigm of cytometry bioinformatics. Data clustering is the most common computational approach to unsupervised identification of cell populations from multidimensional cytometry data. However, interpretation of the identified data clusters is labor-intensive. Certain types of user-defined cell populations are also difficult to identify by fully automated data clustering analysis. Both are roadblocks before a cytometry lab can adopt the data clustering approach for cell population identification in routine use. We found that combining recursive data filtering and clustering with constraints converted from the user manual gating strategy can effectively address these two issues. We named this new approach DAFi: Directed Automated Filtering and Identification of cell populations. Design of DAFi preserves the data-driven characteristics of unsupervised clustering for identifying novel cell subsets, but also makes the results interpretable to experimental scientists through mapping and merging the multidimensional data clusters into the user-defined two-dimensional gating hierarchy. The recursive data filtering process in DAFi helped identify small data clusters which are otherwise difficult to resolve by a single run of the data clustering method due to the statistical interference of the irrelevant major clusters. Our experiment results showed that the proportions of the cell populations identified by DAFi, while being consistent with those by expert centralized manual gating, have smaller technical variances across samples than those from individual manual gating analysis and the nonrecursive data clustering analysis. Compared with manual gating segregation, DAFi-identified cell populations avoided the abrupt cut-offs on the boundaries. DAFi has been implemented to be used with multiple data clustering methods including K-means, FLOCK, FlowSOM, and

  7. Pdx1 and Ngn3 overexpression enhances pancreatic differentiation of mouse ES cell-derived endoderm population.

    Science.gov (United States)

    Kubo, Atsushi; Stull, Robert; Takeuchi, Mitsuaki; Bonham, Kristina; Gouon-Evans, Valerie; Sho, Masayuki; Iwano, Masayuki; Saito, Yoshihiko; Keller, Gordon; Snodgrass, Ralph

    2011-01-01

    In order to define the molecular mechanisms regulating the specification and differentiation of pancreatic β-islet cells, we investigated the effect of upregulating Pdx1 and Ngn3 during the differentiation of the β-islet-like cells from murine embryonic stem (ES) cell-derived activin induced-endoderm. Induced overexpression of Pdx1 resulted in a significant upregulation of insulin (Ins1 and Ins2), and other pancreas-related genes. To enhance the developmental progression from the pancreatic bud to the formation of the endocrine lineages, we induced the overexpression express of Ngn3 together with Pdx1. This combination dramatically increased the level and timing of maximal Ins1 mRNA expression to approximately 100% of that found in the βTC6 insulinoma cell line. Insulin protein and C-peptide expression was confirmed by immunohistochemistry staining. These inductive effects were restricted to c-kit(+) endoderm enriched EB-derived populations suggesting that Pdx1/Ngn3 functions after the specification of pancreatic endoderm. Although insulin secretion was stimulated by various insulin secretagogues, these cells had only limited glucose response. Microarray analysis was used to evaluate the expression of a broad spectrum of pancreatic endocrine cell-related genes as well as genes associated with glucose responses. Taken together, these findings demonstrate the utility of manipulating Pdx1 and Ngn3 expression in a stage-specific manner as an important new strategy for the efficient generation of functionally immature insulin-producing β-islet cells from ES cells.

  8. Pdx1 and Ngn3 overexpression enhances pancreatic differentiation of mouse ES cell-derived endoderm population.

    Directory of Open Access Journals (Sweden)

    Atsushi Kubo

    Full Text Available In order to define the molecular mechanisms regulating the specification and differentiation of pancreatic β-islet cells, we investigated the effect of upregulating Pdx1 and Ngn3 during the differentiation of the β-islet-like cells from murine embryonic stem (ES cell-derived activin induced-endoderm. Induced overexpression of Pdx1 resulted in a significant upregulation of insulin (Ins1 and Ins2, and other pancreas-related genes. To enhance the developmental progression from the pancreatic bud to the formation of the endocrine lineages, we induced the overexpression express of Ngn3 together with Pdx1. This combination dramatically increased the level and timing of maximal Ins1 mRNA expression to approximately 100% of that found in the βTC6 insulinoma cell line. Insulin protein and C-peptide expression was confirmed by immunohistochemistry staining. These inductive effects were restricted to c-kit(+ endoderm enriched EB-derived populations suggesting that Pdx1/Ngn3 functions after the specification of pancreatic endoderm. Although insulin secretion was stimulated by various insulin secretagogues, these cells had only limited glucose response. Microarray analysis was used to evaluate the expression of a broad spectrum of pancreatic endocrine cell-related genes as well as genes associated with glucose responses. Taken together, these findings demonstrate the utility of manipulating Pdx1 and Ngn3 expression in a stage-specific manner as an important new strategy for the efficient generation of functionally immature insulin-producing β-islet cells from ES cells.

  9. Age-Related Change in Vestibular Ganglion Cell Populations in Individuals With Presbycusis and Normal Hearing.

    Science.gov (United States)

    Gluth, Michael B; Nelson, Erik G

    2017-04-01

    We sought to establish that the decline of vestibular ganglion cell counts uniquely correlates with spiral ganglion cell counts, cochlear hair cell counts, and hearing phenotype in individuals with presbycusis. The relationship between aging in the vestibular system and aging in the cochlea is a topic of ongoing investigation. Histopathologic age-related changes the vestibular system may mirror what is seen in the cochlea, but correlations with hearing phenotype and the impact of presbycusis are not well understood. Vestibular ganglion cells, spiral ganglion cells, and cochlear hair cells were counted in specimens from individuals with presbycusis and normal hearing. These were taken from within a large collection of processed human temporal bones. Correlations between histopathology and hearing phenotype were investigated. Vestibular ganglion cell counts were positively correlated with spiral ganglion cell counts and cochlear hair cell counts and were negatively correlated with hearing phenotype. There was no statistical evidence on linear regression to suggest that the relationship between age and cell populations differed significantly according to whether presbycusis was present or not. Superior vestibular ganglion cells were more negatively correlated with age than inferior ganglion cells. No difference in vestibular ganglion cells was noted based on sex. Vestibular ganglion cell counts progressively deteriorate with age, and this loss correlates closely with changes in the cochlea, as well as hearing phenotype. However, these correlations do not appear to be unique in individuals with presbycusis as compared with those with normal hearing.

  10. The bottom-up approach to defining life : deciphering the functional organization of biological cells via multi-objective representation of biological complexity from molecules to cells

    Directory of Open Access Journals (Sweden)

    Sathish ePeriyasamy

    2013-12-01

    Full Text Available In silico representation of cellular systems needs to represent the adaptive dynamics of biological cells, recognizing a cell’s multi-objective topology formed by spatially and temporally cohesive intracellular structures. The design of these models needs to address the hierarchical and concurrent nature of cellular functions and incorporate the ability to self-organise in response to transitions between healthy and pathological phases, and adapt accordingly. The functions of biological systems are constantly evolving, due to the ever changing demands of their environment. Biological systems meet these demands by pursuing objectives, aided by their constituents, giving rise to biological functions. A biological cell is organised into an objective/task hierarchy. These objective hierarchy corresponds to the nested nature of temporally cohesive structures and representing them will facilitate in studying pleiotropy and polygeny by modeling causalities propagating across multiple interconnected intracellular processes. Although biological adaptations occur in physiological, developmental and reproductive timescales, the paper is focused on adaptations that occur within physiological timescales, where the biomolecular activities contributing to functional organisation, play a key role in cellular physiology. The paper proposes a multi-scale and multi-objective modelling approach from the bottom-up by representing temporally cohesive structures for multi-tasking of intracellular processes. Further the paper characterises the properties and constraints that are consequential to the organisational and adaptive dynamics in biological cells.

  11. A comparison of pectoralis versus lumbar skeletal muscle indices for defining sarcopenia in diffuse large B-cell lymphoma - two are better than one.

    Science.gov (United States)

    Go, Se-Il; Park, Mi Jung; Song, Haa-Na; Kim, Hoon-Gu; Kang, Myoung Hee; Kang, Jung Hun; Kim, Hye Ree; Lee, Gyeong-Won

    2017-07-18

    Sarcopenia is known to be associated with poor clinical outcome in patients with diffuse large B-cell lymphoma (DLBCL). There is no consensus concerning the optimal method to define sarcopenia in DLBCL. We retrospectively reviewed 193 DLBCL patients treated with rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) therapy. Sarcopenia was classified by the region where the pretreatment skeletal muscle index (SMI) was measured. Both the sarcopenia-L3 and sarcopenia-pectoralis muscle (PM) groups had increased incidences of severe treatment-related toxicities and treatment discontinuation compared with the non-sarcopenia-L3 and non-sarcopenia-PM groups, respectively. The sarcopenia-L3 and non-sarcopenia-L3 groups had 5-year overall survival (OS) rates of 40.5% and 67.8% (p sarcopenia-PM and non-sarcopenia-PM groups had 5-year OS rates of 35.9% and 69.0% (p sarcopenia-L3 alone and sarcopenia-PM alone groups were compared, there were no differences in baseline characteristics, treatment toxicity, or survival. In multivariate analysis, when compared with the non-sarcopenia-both group, OS was significantly worse in the sarcopenia-both group (HR, 2.480; 95% CI, 1.284 - 4.792; p = 0.007), but not in patients with either sarcopenia-L3 alone or sarcopenia-PM alone (p = 0.151). L3- and PM-SMIs are equally useful to define sarcopenia, which is related to intolerance to R-CHOP therapy and to worse survival in patients with DLBCL. More prognostic information can be obtained when these two SMIs are combined to define sarcopenia.

  12. Bone marrow-derived cells in the population of spinal microglia after peripheral nerve injury

    Science.gov (United States)

    Tashima, Ryoichi; Mikuriya, Satsuki; Tomiyama, Daisuke; Shiratori-Hayashi, Miho; Yamashita, Tomohiro; Kohro, Yuta; Tozaki-Saitoh, Hidetoshi; Inoue, Kazuhide; Tsuda, Makoto

    2016-01-01

    Accumulating evidence indicates that peripheral nerve injury (PNI) activates spinal microglia that are necessary for neuropathic pain. Recent studies using bone marrow (BM) chimeric mice have reported that after PNI, circulating BM-derived cells infiltrate into the spinal cord and differentiate into microglia-like cells. This raises the possibility that the population of spinal microglia after PNI may be heterogeneous. However, the infiltration of BM cells in the spinal cord remains controversial because of experimental adverse effects of strong irradiation used for generating BM chimeric mice. In this study, we evaluated the PNI-induced spinal infiltration of BM-derived cells not only by irradiation-induced myeloablation with various conditioning regimens, but also by parabiosis and mice with genetically labelled microglia, models without irradiation and BM transplantation. Results obtained from these independent approaches provide compelling evidence indicating little contribution of circulating BM-derived cells to the population of spinal microglia after PNI. PMID:27005516

  13. Studies on the termination of immunological tolerance in the mouse thymus cell population after irradiation

    International Nuclear Information System (INIS)

    Amagai, Takashi

    1981-01-01

    Immunological tolerance in the mouse thymus cell population induced by the intravenous injection of deaggregated bovine gamma globulin was terminated by whole body irradiation. After irradiation, the weight of the thymus recovered biphasically, and the termination of tolerance occurred as early as in the first phase. Both Thy-1 antigen expression and helper activity of the thymus cell population in irradiated mice recovered in parallel with the recovery of the thymus weight. Sensitivity of the regenerating thymus cells to the tolerogen was not different from that of the normal thymus cells. The first phase of thymus regeneration may be caused by the proliferation and differentiation of relatively radioresistant and tolerogen insensitive precursors residing in the thymus. Tolerogen and/or immunogen reactive thymus cells may originate from the precursor. (author)

  14. The effect of ultraviolet light on arrested human diploid cell populations

    International Nuclear Information System (INIS)

    Kantor, G.J.; Warner, C.; Hull, D.R.

    1977-01-01

    The results of the experiments to determine an effect of UV (254 nm) on human diploid fibroblasts (HDF) arrested with respect to division by using 0.5% fetal calf serum in the culture medium are reported. A fraction of cells from irradiated arrested populations, maintained in the arrested state post-irradiation, was lost from the populations. The extent of cell loss was fluence-dependent and cell strain specific. A Xeroderma pigmentosum cell strain was more sensitive to UV than were normal HDF. No difference in sensitivity were observed when arrested populations established from normal HDF populations of various in vitro ages were used. The length of the pre-irradiation arrested period affected the sensitivity of normal HDF, which appeared more resistant at longer arrested periods, but not the sensitivity of arrested Xeroderma populations. These results suggest that DNA repair processes play a role in maintaining irradiated cells in the arrested state. The suggestion is made that the lethal event caused by UV is an effect on transcription leading to an inhibition of required protein synthesis. (author)

  15. From invasion to latency: intracellular noise and cell motility as key controls of the competition between resource-limited cellular populations

    KAUST Repository

    Guerrero, Pilar

    2015-04-02

    © 2015, Springer-Verlag Berlin Heidelberg. In this paper we analyse stochastic models of the competition between two resource-limited cell populations which differ in their response to nutrient availability: the resident population exhibits a switch-like response behaviour while the invading population exhibits a bistable response. We investigate how noise in the intracellular regulatory pathways and cell motility influence the fate of the incumbent and invading populations. We focus initially on a spatially homogeneous system and study in detail the role of intracellular noise. We show that in such well-mixed systems, two distinct regimes exist: In the low (intracellular) noise limit, the invader has the ability to invade the resident population, whereas in the high noise regime competition between the two populations is found to be neutral and, in accordance with neutral evolution theory, invasion is a random event. Careful examination of the system dynamics leads us to conclude that (i) even if the invader is unable to invade, the distribution of survival times, PS(t), has a fat-tail behaviour (PS(t)∼t-1) which implies that small colonies of mutants can coexist with the resident population for arbitrarily long times, and (ii) the bistable structure of the invading population increases the stability of the latent population, thus increasing their long-term likelihood of survival, by decreasing the intensity of the noise at the population level. We also examine the effects of spatial inhomogeneity. In the low noise limit we find that cell motility is positively correlated with the aggressiveness of the invader as