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Sample records for cells yettheir extracellular

  1. Extracellular Molecules Involved in Cancer Cell Invasion

    International Nuclear Information System (INIS)

    Stivarou, Theodora; Patsavoudi, Evangelia

    2015-01-01

    Nowadays it is perfectly clear that understanding and eradicating cancer cell invasion and metastasis represent the crucial, definitive points in cancer therapeutics. During the last two decades there has been a great interest in the understanding of the extracellular molecular mechanisms involved in cancer cell invasion. In this review, we highlight the findings concerning these processes, focusing in particular on extracellular molecules, including extracellular matrix proteins and their receptors, growth factors and their receptors, matrix metalloproteinases and extracellular chaperones. We report the molecular mechanisms underlying the important contribution of this pool of molecules to the complex, multi-step phenomenon of cancer cell invasion

  2. Extracellular Molecules Involved in Cancer Cell Invasion

    Directory of Open Access Journals (Sweden)

    Theodora Stivarou

    2015-01-01

    Full Text Available Nowadays it is perfectly clear that understanding and eradicating cancer cell invasion and metastasis represent the crucial, definitive points in cancer therapeutics. During the last two decades there has been a great interest in the understanding of the extracellular molecular mechanisms involved in cancer cell invasion. In this review, we highlight the findings concerning these processes, focusing in particular on extracellular molecules, including extracellular matrix proteins and their receptors, growth factors and their receptors, matrix metalloproteinases and extracellular chaperones. We report the molecular mechanisms underlying the important contribution of this pool of molecules to the complex, multi-step phenomenon of cancer cell invasion.

  3. Stem cell extracellular vesicles and kidney injury

    OpenAIRE

    Grange, Cristina; Iampietro, Corinne; Bussolati, Benedetta

    2017-01-01

    Extracellular vesicles (EVs) appear as a new promising cell-free therapy for acute and chronic renal diseases. EVs retain characteristics of the cell of origin and those derived from stem cells may mimic their regenerative properties per se. In fact, EVs contain many active molecules such as proteins and RNA species that act on target cells through different mechanisms, stimulating proliferation and angiogenesis and reducing apoptosis and inflammation. There are several reports that demonstra...

  4. Extracellular matrix components direct porcine muscle stem cell behavior

    International Nuclear Information System (INIS)

    Wilschut, Karlijn J.; Haagsman, Henk P.; Roelen, Bernard A.J.

    2010-01-01

    In muscle tissue, extracellular matrix proteins, together with the vasculature system, muscle-residence cells and muscle fibers, create the niche for muscle stem cells. The niche is important in controlling proliferation and directing differentiation of muscle stem cells to sustain muscle tissue. Mimicking the extracellular muscle environment improves tools exploring the behavior of primary muscle cells. Optimizing cell culture conditions to maintain muscle commitment is important in stem cell-based studies concerning toxicology screening, ex vivo skeletal muscle tissue engineering and in the enhancement of clinical efficiency. We used the muscle extracellular matrix proteins collagen type I, fibronectin, laminin, and also gelatin and Matrigel as surface coatings of tissue culture plastic to resemble the muscle extracellular matrix. Several important factors that determine myogenic commitment of the primary muscle cells were characterized by quantitative real-time RT-PCR and immunofluorescence. Adhesion of high PAX7 expressing satellite cells was improved if the cells were cultured on fibronectin or laminin coatings. Cells cultured on Matrigel and laminin coatings showed dominant integrin expression levels and exhibited an activated Wnt pathway. Under these conditions both stem cell proliferation and myogenic differentiation capacity were superior if compared to cells cultured on collagen type I, fibronectin and gelatin. In conclusion, Matrigel and laminin are the preferred coatings to sustain the proliferation and myogenic differentiation capacity of the primary porcine muscle stem cells, when cells are removed from their natural environment for in vitro culture.

  5. Extracellular matrix components direct porcine muscle stem cell behavior

    Energy Technology Data Exchange (ETDEWEB)

    Wilschut, Karlijn J. [Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 104, 3584 CM, Utrecht (Netherlands); Haagsman, Henk P. [Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL, Utrecht (Netherlands); Roelen, Bernard A.J., E-mail: b.a.j.roelen@uu.nl [Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 104, 3584 CM, Utrecht (Netherlands)

    2010-02-01

    In muscle tissue, extracellular matrix proteins, together with the vasculature system, muscle-residence cells and muscle fibers, create the niche for muscle stem cells. The niche is important in controlling proliferation and directing differentiation of muscle stem cells to sustain muscle tissue. Mimicking the extracellular muscle environment improves tools exploring the behavior of primary muscle cells. Optimizing cell culture conditions to maintain muscle commitment is important in stem cell-based studies concerning toxicology screening, ex vivo skeletal muscle tissue engineering and in the enhancement of clinical efficiency. We used the muscle extracellular matrix proteins collagen type I, fibronectin, laminin, and also gelatin and Matrigel as surface coatings of tissue culture plastic to resemble the muscle extracellular matrix. Several important factors that determine myogenic commitment of the primary muscle cells were characterized by quantitative real-time RT-PCR and immunofluorescence. Adhesion of high PAX7 expressing satellite cells was improved if the cells were cultured on fibronectin or laminin coatings. Cells cultured on Matrigel and laminin coatings showed dominant integrin expression levels and exhibited an activated Wnt pathway. Under these conditions both stem cell proliferation and myogenic differentiation capacity were superior if compared to cells cultured on collagen type I, fibronectin and gelatin. In conclusion, Matrigel and laminin are the preferred coatings to sustain the proliferation and myogenic differentiation capacity of the primary porcine muscle stem cells, when cells are removed from their natural environment for in vitro culture.

  6. Focus on Extracellular Vesicles: Therapeutic Potential of Stem Cell-Derived Extracellular Vesicles

    Directory of Open Access Journals (Sweden)

    Bin Zhang

    2016-02-01

    Full Text Available The intense research focus on stem and progenitor cells could be attributed to their differentiation potential to generate new cells to replace diseased or lost cells in many highly intractable degenerative diseases, such as Alzheimer disease, multiple sclerosis, and heart diseases. However, experimental and clinical studies have increasingly attributed the therapeutic efficacy of these cells to their secretion. While stem and progenitor cells secreted many therapeutic molecules, none of these molecules singly or in combination could recapitulate the functional effects of stem cell transplantations. Recently, it was reported that extracellular vesicles (EVs could recapitulate the therapeutic effects of stem cell transplantation. Based on the observations reported thus far, the prevailing hypothesis is that stem cell EVs exert their therapeutic effects by transferring biologically active molecules such as proteins, lipids, mRNA, and microRNA from the stem cells to injured or diseased cells. In this respect, stem cell EVs are similar to EVs from other cell types. They are both primarily vehicles for intercellular communication. Therefore, the differentiating factor is likely due to the composition of their cargo. The cargo of EVs from different cell types are known to include a common set of proteins and also proteins that reflect the cell source of the EVs and the physiological or pathological state of the cell source. Hence, elucidation of the stem cell EV cargo would provide an insight into the multiple physiological or biochemical changes necessary to affect the many reported stem cell-based therapeutic outcomes in a variety of experimental models and clinical trials.

  7. Intestinal Stem Cell Niche: The Extracellular Matrix and Cellular Components

    Directory of Open Access Journals (Sweden)

    Laween Meran

    2017-01-01

    Full Text Available The intestinal epithelium comprises a monolayer of polarised columnar cells organised along the crypt-villus axis. Intestinal stem cells reside at the base of crypts and are constantly nourished by their surrounding niche for maintenance, self-renewal, and differentiation. The cellular microenvironment including the adjacent Paneth cells, stromal cells, smooth muscle cells, and neural cells as well as the extracellular matrix together constitute the intestinal stem cell niche. A dynamic regulatory network exists among the epithelium, stromal cells, and the matrix via complex signal transduction to maintain tissue homeostasis. Dysregulation of these biological or mechanical signals could potentially lead to intestinal injury and disease. In this review, we discuss the role of different intestinal stem cell niche components and dissect the interaction between dynamic matrix factors and regulatory signalling during intestinal stem cell homeostasis.

  8. Activation of retinal glial (Müller cells by extracellular ATP induces pronounced increases in extracellular H+ flux.

    Directory of Open Access Journals (Sweden)

    Boriana K Tchernookova

    Full Text Available Small alterations in extracellular acidity are potentially important modulators of neuronal signaling within the vertebrate retina. Here we report a novel extracellular acidification mechanism mediated by glial cells in the retina. Using self-referencing H+-selective microelectrodes to measure extracellular H+ fluxes, we show that activation of retinal Müller (glial cells of the tiger salamander by micromolar concentrations of extracellular ATP induces a pronounced extracellular H+ flux independent of bicarbonate transport. ADP, UTP and the non-hydrolyzable analog ATPγs at micromolar concentrations were also potent stimulators of extracellular H+ fluxes, but adenosine was not. The extracellular H+ fluxes induced by ATP were mimicked by the P2Y1 agonist MRS 2365 and were significantly reduced by the P2 receptor blockers suramin and PPADS, suggesting activation of P2Y receptors. Bath-applied ATP induced an intracellular rise in calcium in Müller cells; both the calcium rise and the extracellular H+ fluxes were significantly attenuated when calcium re-loading into the endoplasmic reticulum was inhibited by thapsigargin and when the PLC-IP3 signaling pathway was disrupted with 2-APB and U73122. The anion transport inhibitor DIDS also markedly reduced the ATP-induced increase in H+ flux while SITS had no effect. ATP-induced H+ fluxes were also observed from Müller cells isolated from human, rat, monkey, skate and lamprey retinae, suggesting a highly evolutionarily conserved mechanism of potential general importance. Extracellular ATP also induced significant increases in extracellular H+ flux at the level of both the outer and inner plexiform layers in retinal slices of tiger salamander which was significantly reduced by suramin and PPADS. We suggest that the novel H+ flux mediated by ATP-activation of Müller cells and of other glia as well may be a key mechanism modulating neuronal signaling in the vertebrate retina and throughout the brain.

  9. Extracellular matrix-derived hydrogels for dental stem cell delivery

    OpenAIRE

    Viswanath, Aiswarya; Vanacker, Julie; Germain, Loic; Leprince, Julien G.; Diogenes, Anibal; Shakesheff, Kevin M.; White, Lisa J.; des Rieux, Anne

    2016-01-01

    Decellularised mammalian extracellular matrices (ECM) have been widely accepted as an ideal substrate for repair and remodelling of numerous tissues in clinical and pre-clinical studies. Recent studies have demonstrated the ability of ECM scaffolds derived from site-specific homologous tissues to direct cell differentiation. The present study investigated the suitability of hydrogels derived from different source tissues: bone, spinal cord and dentine, as suitable carriers to deliver human ap...

  10. Stem Cell Extracellular Vesicles: Extended Messages of Regeneration

    Science.gov (United States)

    Riazifar, Milad; Pone, Egest J.; Lötvall, Jan; Zhao, Weian

    2017-01-01

    Stem cells are critical to maintaining steady-state organ homeostasis and regenerating injured tissues. Recent intriguing reports implicate extracellular vesicles (EVs) as carriers for the distribution of morphogens and growth and differentiation factors from tissue parenchymal cells to stem cells, and conversely, stem cell–derived EVs carrying certain proteins and nucleic acids can support healing of injured tissues. We describe approaches to make use of engineered EVs as technology platforms in therapeutics and diagnostics in the context of stem cells. For some regenerative therapies, natural and engineered EVs from stem cells may be superior to single-molecule drugs, biologics, whole cells, and synthetic liposome or nanoparticle formulations because of the ease of bioengineering with multiple factors while retaining superior biocompatibility and biostability and posing fewer risks for abnormal differentiation or neoplastic transformation. Finally, we provide an overview of current challenges and future directions of EVs as potential therapeutic alternatives to cells for clinical applications. PMID:27814025

  11. Extracellular adenosine controls NKT-cell-dependent hepatitis induction.

    Science.gov (United States)

    Subramanian, Meenakshi; Kini, Radhika; Madasu, Manasa; Ohta, Akiko; Nowak, Michael; Exley, Mark; Sitkovsky, Michail; Ohta, Akio

    2014-04-01

    Extracellular adenosine regulates inflammatory responses via the A2A adenosine receptor (A2AR). A2AR deficiency results in much exaggerated acute hepatitis, indicating nonredundancy of adenosine-A2AR pathway in inhibiting immune activation. To identify a critical target of immunoregulatory effect of extracellular adenosine, we focused on NKT cells, which play an indispensable role in hepatitis. An A2AR agonist abolished NKT-cell-dependent induction of acute hepatitis by concanavalin A (Con A) or α-galactosylceramide in mice, corresponding to downregulation of activation markers and cytokines in NKT cells and of NK-cell co-activation. These results show that A2AR signaling can downregulate NKT-cell activation and suppress NKT-cell-triggered inflammatory responses. Next, we hypothesized that NKT cells might be under physiological control of the adenosine-A2AR pathway. Indeed, both Con A and α-galactosylceramide induced more severe hepatitis in A2AR-deficient mice than in WT controls. Transfer of A2AR-deficient NKT cells into A2AR-expressing recipients resulted in exaggeration of Con A-induced liver damage, suggesting that NKT-cell activation is controlled by endogenous adenosine via A2AR, and this physiological regulatory mechanism of NKT cells is critical in the control of tissue-damaging inflammation. The current study suggests the possibility to manipulate NKT-cell activity in inflammatory disorders through intervention to the adenosine-A2AR pathway. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Cell stiffness, contractile stress and the role of extracellular matrix

    International Nuclear Information System (INIS)

    An, Steven S.; Kim, Jina; Ahn, Kwangmi; Trepat, Xavier; Drake, Kenneth J.; Kumar, Sarvesh; Ling, Guoyu; Purington, Carolyn; Rangasamy, Tirumalai; Kensler, Thomas W.; Mitzner, Wayne; Fredberg, Jeffrey J.; Biswal, Shyam

    2009-01-01

    Here we have assessed the effects of extracellular matrix (ECM) composition and rigidity on mechanical properties of the human airway smooth muscle (ASM) cell. Cell stiffness and contractile stress showed appreciable changes from the most relaxed state to the most contracted state: we refer to the maximal range of these changes as the cell contractile scope. The contractile scope was least when the cell was adherent upon collagen V, followed by collagen IV, laminin, and collagen I, and greatest for fibronectin. Regardless of ECM composition, upon adherence to increasingly rigid substrates, the ASM cell positively regulated expression of antioxidant genes in the glutathione pathway and heme oxygenase, and disruption of a redox-sensitive transcription factor, nuclear erythroid 2 p45-related factor (Nrf2), culminated in greater contractile scope. These findings provide biophysical evidence that ECM differentially modulates muscle contractility and, for the first time, demonstrate a link between muscle contractility and Nrf2-directed responses.

  13. Cell stiffness, contractile stress and the role of extracellular matrix

    Energy Technology Data Exchange (ETDEWEB)

    An, Steven S., E-mail: san@jhsph.edu [Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, 615 N. Wolfe Street, Room E-7616, Baltimore, MD 21205 (United States); Kim, Jina [Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, 615 N. Wolfe Street, Room E-7616, Baltimore, MD 21205 (United States); Ahn, Kwangmi [Division of Biostatistics, Penn State College of Medicine, Hershey, PA 17033 (United States); Trepat, Xavier [CIBER, Enfermedades Respiratorias, 07110 Bunyola (Spain); Drake, Kenneth J. [Division of Molecular and Integrative Physiological Sciences, Harvard School of Public Health, Boston, MA 02115 (United States); Kumar, Sarvesh; Ling, Guoyu; Purington, Carolyn; Rangasamy, Tirumalai; Kensler, Thomas W.; Mitzner, Wayne [Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, 615 N. Wolfe Street, Room E-7616, Baltimore, MD 21205 (United States); Fredberg, Jeffrey J. [Division of Molecular and Integrative Physiological Sciences, Harvard School of Public Health, Boston, MA 02115 (United States); Biswal, Shyam [Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, 615 N. Wolfe Street, Room E-7616, Baltimore, MD 21205 (United States); Division of Pulmonary and Critical Care Medicine, Johns Hopkins School of Medicine, Baltimore, MD 21205 (United States)

    2009-05-15

    Here we have assessed the effects of extracellular matrix (ECM) composition and rigidity on mechanical properties of the human airway smooth muscle (ASM) cell. Cell stiffness and contractile stress showed appreciable changes from the most relaxed state to the most contracted state: we refer to the maximal range of these changes as the cell contractile scope. The contractile scope was least when the cell was adherent upon collagen V, followed by collagen IV, laminin, and collagen I, and greatest for fibronectin. Regardless of ECM composition, upon adherence to increasingly rigid substrates, the ASM cell positively regulated expression of antioxidant genes in the glutathione pathway and heme oxygenase, and disruption of a redox-sensitive transcription factor, nuclear erythroid 2 p45-related factor (Nrf2), culminated in greater contractile scope. These findings provide biophysical evidence that ECM differentially modulates muscle contractility and, for the first time, demonstrate a link between muscle contractility and Nrf2-directed responses.

  14. Nanostructured gold microelectrodes for extracellular recording from electrogenic cells

    Energy Technology Data Exchange (ETDEWEB)

    Brueggemann, D; Wolfrum, B; Maybeck, V; Mourzina, Y; Jansen, M; Offenhaeusser, A, E-mail: a.offenhaeusser@fz-juelich.de [Institute of Complex Systems and Peter Gruenberg Institute: Bioelectronics (ICS8/PGI8), Forschungszentrum Juelich GmbH, Leo-Brandt-Strasse, 52428 Juelich (Germany); Juelich-Aachen Research Alliance-Fundamental of Future Information Technology (JARA-FIT) (Germany)

    2011-07-01

    We present a new biocompatible nanostructured microelectrode array for extracellular signal recording from electrogenic cells. Microfabrication techniques were combined with a template-assisted approach using nanoporous aluminum oxide to develop gold nanopillar electrodes. The nanopillars were approximately 300-400 nm high and had a diameter of 60 nm. Thus, they yielded a higher surface area of the electrodes resulting in a decreased impedance compared to planar electrodes. The interaction between the large-scale gold nanopillar arrays and cardiac muscle cells (HL-1) was investigated via focused ion beam milling. In the resulting cross-sections we observed a tight coupling between the HL-1 cells and the gold nanostructures. However, the cell membranes did not bend into the cleft between adjacent nanopillars due to the high pillar density. We performed extracellular potential recordings from HL-1 cells with the nanostructured microelectrode arrays. The maximal amplitudes recorded with the nanopillar electrodes were up to 100% higher than those recorded with planar gold electrodes. Increasing the aspect ratio of the gold nanopillars and changing the geometrical layout can further enhance the signal quality in the future.

  15. Nanostructured gold microelectrodes for extracellular recording from electrogenic cells.

    Science.gov (United States)

    Brüggemann, D; Wolfrum, B; Maybeck, V; Mourzina, Y; Jansen, M; Offenhäusser, A

    2011-07-01

    We present a new biocompatible nanostructured microelectrode array for extracellular signal recording from electrogenic cells. Microfabrication techniques were combined with a template-assisted approach using nanoporous aluminum oxide to develop gold nanopillar electrodes. The nanopillars were approximately 300-400 nm high and had a diameter of 60 nm. Thus, they yielded a higher surface area of the electrodes resulting in a decreased impedance compared to planar electrodes. The interaction between the large-scale gold nanopillar arrays and cardiac muscle cells (HL-1) was investigated via focused ion beam milling. In the resulting cross-sections we observed a tight coupling between the HL-1 cells and the gold nanostructures. However, the cell membranes did not bend into the cleft between adjacent nanopillars due to the high pillar density. We performed extracellular potential recordings from HL-1 cells with the nanostructured microelectrode arrays. The maximal amplitudes recorded with the nanopillar electrodes were up to 100% higher than those recorded with planar gold electrodes. Increasing the aspect ratio of the gold nanopillars and changing the geometrical layout can further enhance the signal quality in the future.

  16. Extracellular Matrix as a Regulator of Epidermal Stem Cell Fate.

    Science.gov (United States)

    Chermnykh, Elina; Kalabusheva, Ekaterina; Vorotelyak, Ekaterina

    2018-03-27

    Epidermal stem cells reside within the specific anatomic location, called niche, which is a microenvironment that interacts with stem cells to regulate their fate. Regulation of many important processes, including maintenance of stem cell quiescence, self-renewal, and homeostasis, as well as the regulation of division and differentiation, are common functions of the stem cell niche. As it was shown in multiple studies, extracellular matrix (ECM) contributes a lot to stem cell niches in various tissues, including that of skin. In epidermis, ECM is represented, primarily, by a highly specialized ECM structure, basement membrane (BM), which separates the epidermal and dermal compartments. Epidermal stem cells contact with BM, but when they lose the contact and migrate to the overlying layers, they undergo terminal differentiation. When considering all of these factors, ECM is of fundamental importance in regulating epidermal stem cells maintenance, proper mobilization, and differentiation. Here, we summarize the remarkable progress that has recently been made in the research of ECM role in regulating epidermal stem cell fate, paying special attention to the hair follicle stem cell niche. We show that the destruction of ECM components impairs epidermal stem cell morphogenesis and homeostasis. A deep understanding of ECM molecular structure as well as the development of in vitro system for stem cell maintaining by ECM proteins may bring us to developing new approaches for regenerative medicine.

  17. Extracellular Alkalinization as a Defense Response in Potato Cells.

    Science.gov (United States)

    Moroz, Natalia; Fritch, Karen R; Marcec, Matthew J; Tripathi, Diwaker; Smertenko, Andrei; Tanaka, Kiwamu

    2017-01-01

    A quantitative and robust bioassay to assess plant defense response is important for studies of disease resistance and also for the early identification of disease during pre- or non-symptomatic phases. An increase in extracellular pH is known to be an early defense response in plants. In this study, we demonstrate extracellular alkalinization as a defense response in potatoes. Using potato suspension cell cultures, we observed an alkalinization response against various pathogen- and plant-derived elicitors in a dose- and time-dependent manner. We also assessed the defense response against a variety of potato pathogens, such as protists ( Phytophthora infestans and Spongospora subterranea ) and fungi ( Verticillium dahliae and Colletotrichum coccodes ). Our results show that extracellular pH increases within 30 min in proportion to the number of pathogen spores added. Consistently with the alkalinization effect, the higher transcription level of several defense-related genes and production of reactive oxygen species was observed. Our results demonstrate that the alkalinization response is an effective marker to study early stages of defense response in potatoes.

  18. An immunofluorescence assay for extracellular matrix components highlights the role of epithelial cells in producing a stable, fibrillar extracellular matrix

    Directory of Open Access Journals (Sweden)

    Omar S. Qureshi

    2017-10-01

    Full Text Available Activated fibroblasts are considered major drivers of fibrotic disease progression through the production of excessive extracellular matrix (ECM in response to signals from damaged epithelial and inflammatory cells. Nevertheless, epithelial cells are capable of expressing components of the ECM, cross-linking enzymes that increase its stability and are sensitive to factors involved in the early stages of fibrosis. We therefore wanted to test the hypothesis that epithelial cells can deposit ECM in response to stimulation in a comparable manner to fibroblasts. We performed immunofluorescence analysis of components of stable, mature extracellular matrix produced by primary human renal proximal tubular epithelial cells and renal fibroblasts in response to cytokine stimulation. Whilst fibroblasts produced a higher basal level of extracellular matrix components, epithelial cells were able to deposit significant levels of fibronectin, collagen I, III and IV in response to cytokine stimulation. In response to hypoxia, epithelial cells showed an increase in collagen IV deposition but not in response to the acute stress stimuli aristolochic acid or hydrogen peroxide. When epithelial cells were in co-culture with fibroblasts we observed significant increases in the level of matrix deposition which could be reduced by transforming growth factor beta (TGF-β blockade. Our results highlight the role of epithelial cells acting as efficient producers of stable extracellular matrix which could contribute to renal tubule thickening in fibrosis.

  19. Cells involved in extracellular matrix remodeling after acute myocardial infarction

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, Larissa Ferraz [Faculdade de Medicina do ABC, Santo André, SP (Brazil); Mataveli, Fábio D’Aguiar [Universidade Federal de São Paulo, São Paulo, SP (Brazil); Mader, Ana Maria Amaral Antônio; Theodoro, Thérèse Rachell [Faculdade de Medicina do ABC, Santo André, SP (Brazil); Justo, Giselle Zenker; Pinhal, Maria Aparecida da Silva [Universidade Federal de São Paulo, São Paulo, SP (Brazil)

    2015-07-01

    Evaluate the effects of VEGF{sub 165} gene transfer in the process of remodeling of the extracellular matrix after an acute myocardial infarct. Wistar rats were submitted to myocardial infarction, after the ligation of the left descending artery, and the left ventricle ejection fraction was used to classify the infarcts into large and small. The animals were divided into groups of ten, according to the size of infarcted area (large or small), and received or not VEGF{sub 165} treatment. Evaluation of different markers was performed using immunohistochemistry and digital quantification. The primary antibodies used in the analysis were anti-fibronectin, anti-vimentin, anti-CD44, anti-E-cadherin, anti-CD24, anti-alpha-1-actin, and anti-PCNA. The results were expressed as mean and standard error, and analyzed by ANOVA, considering statistically significant if p≤0.05. There was a significant increase in the expression of undifferentiated cell markers, such as fibronectin (protein present in the extracellular matrix) and CD44 (glycoprotein present in the endothelial cells). However, there was decreased expression of vimentin and PCNA, indicating a possible decrease in the process of cell proliferation after treatment with VEGF{sub 165}. Markers of differentiated cells, E-cadherin (adhesion protein between myocardial cells), CD24 (protein present in the blood vessels), and alpha-1-actin (specific myocyte marker), showed higher expression in the groups submitted to gene therapy, compared to non-treated group. The value obtained by the relation between alpha-1-actin and vimentin was approximately three times higher in the groups treated with VEGF{sub 165}, suggesting greater tissue differentiation. The results demonstrated the important role of myocytes in the process of tissue remodeling, confirming that VEGF{sub 165} seems to provide a protective effect in the treatment of acute myocardial infarct.

  20. Cells involved in extracellular matrix remodeling after acute myocardial infarction

    International Nuclear Information System (INIS)

    Garcia, Larissa Ferraz; Mataveli, Fábio D’Aguiar; Mader, Ana Maria Amaral Antônio; Theodoro, Thérèse Rachell; Justo, Giselle Zenker; Pinhal, Maria Aparecida da Silva

    2015-01-01

    Evaluate the effects of VEGF_1_6_5 gene transfer in the process of remodeling of the extracellular matrix after an acute myocardial infarct. Wistar rats were submitted to myocardial infarction, after the ligation of the left descending artery, and the left ventricle ejection fraction was used to classify the infarcts into large and small. The animals were divided into groups of ten, according to the size of infarcted area (large or small), and received or not VEGF_1_6_5 treatment. Evaluation of different markers was performed using immunohistochemistry and digital quantification. The primary antibodies used in the analysis were anti-fibronectin, anti-vimentin, anti-CD44, anti-E-cadherin, anti-CD24, anti-alpha-1-actin, and anti-PCNA. The results were expressed as mean and standard error, and analyzed by ANOVA, considering statistically significant if p≤0.05. There was a significant increase in the expression of undifferentiated cell markers, such as fibronectin (protein present in the extracellular matrix) and CD44 (glycoprotein present in the endothelial cells). However, there was decreased expression of vimentin and PCNA, indicating a possible decrease in the process of cell proliferation after treatment with VEGF_1_6_5. Markers of differentiated cells, E-cadherin (adhesion protein between myocardial cells), CD24 (protein present in the blood vessels), and alpha-1-actin (specific myocyte marker), showed higher expression in the groups submitted to gene therapy, compared to non-treated group. The value obtained by the relation between alpha-1-actin and vimentin was approximately three times higher in the groups treated with VEGF_1_6_5, suggesting greater tissue differentiation. The results demonstrated the important role of myocytes in the process of tissue remodeling, confirming that VEGF_1_6_5 seems to provide a protective effect in the treatment of acute myocardial infarct

  1. Cell-extracellular matrix and cell-cell adhesion are linked by syndecan-4

    DEFF Research Database (Denmark)

    Pakideeri Karat, Sandeep Gopal; Multhaupt, Hinke A B; Pocock, Roger

    2017-01-01

    Cell-extracellular matrix (ECM) and cell-cell junctions that employ microfilaments are sites of tension. They are important for tissue repair, morphogenetic movements and can be emblematic of matrix contraction in fibrotic disease and the stroma of solid tumors. One cell surface receptor, syndecan...... calcium. While it is known that cell-ECM and cell-cell junctions may be linked, possible roles for syndecans in this process are not understood. Here we show that wild type primary fibroblasts and those lacking syndecan-4 utilize different cadherins in their adherens junctions and that tension is a major...... factor in this differential response. This corresponds to the reduced ability of fibroblasts lacking syndecan-4 to exert tension on the ECM and we now show that this may extend to reduced tension in cell-cell adhesion....

  2. Immunoscreening of the extracellular proteome of colorectal cancer cells

    International Nuclear Information System (INIS)

    Klein-Scory, Susanne; Schwarte-Waldhoff, Irmgard; Kübler, Salwa; Diehl, Hanna; Eilert-Micus, Christina; Reinacher-Schick, Anke; Stühler, Kai; Warscheid, Bettina; Meyer, Helmut E; Schmiegel, Wolff

    2010-01-01

    The release of proteins from tumors can trigger an immune response in cancer patients involving T lymphocytes and B lymphocytes, which results in the generation of antibodies to tumor-derived proteins. Many studies aim to use humoral immune responses, namely autoantibody profiles, directly, as clinical biomarkers. Alternatively, the antibody immune response as an amplification system for tumor associated alterations may be used to indicate putative protein biomarkers with high sensitivity. Aiming at the latter approach we here have implemented an autoantibody profiling strategy which particularly focuses on proteins released by tumor cells in vitro: the so-called secretome. For immunoscreening, the extracellular proteome of five colorectal cancer cell lines was resolved on 2D gels, immobilized on PVDF membranes and used for serological screening with individual sera from 21 colorectal cancer patients and 24 healthy controls. All of the signals from each blot were assigned to a master map, and autoantigen candidates were defined based of the pattern of immunoreactivities. The corresponding proteins were isolated from preparative gels, identified by MALDI-MS and/or by nano-HPLC/ESI-MS/MS and exemplarily confirmed by duplex Western blotting combining the human serum samples with antibodies directed against the protein(s) of interest. From 281 secretome proteins stained with autoantibodies in total we first defined the 'background patterns' of frequently immunoreactive extracellular proteins in healthy and diseased people. An assignment of these proteins, among them many nominally intracellular proteins, to the subset of exosomal proteins within the secretomes revealed a large overlap. On this basis we defined and consequently confirmed novel biomarker candidates such as the extreme C-terminus of the extracellular matrix protein agrin within the set of cancer-enriched immunorectivities. Our findings suggest, first, that autoantibody responses may be due, in

  3. Extracellular delivery induced by ultrasound and microbubbles in cells

    Science.gov (United States)

    Hussein, Farah; Antonescu, Costin; Karshafian, Raffi

    2017-03-01

    Ultrasound and microbubble treatment (USMB) can enhance the intracellular uptake of molecules, which otherwise would be excluded from the cell, through USMB-mediated transient membrane disruption and through enhanced endocytosis. However, the effect of USMB on the outward movement of molecules from cells is not well understood. This study investigates the effects of USMB on the release of molecules from various cellular compartments including cytoplasm, lysosomes, and recycling endosomes. In vitro ARPE-19 (RPE henceforth) cells were loaded with Alexa fluor-labeled transferrin as a marker for recycling endosomes, LAMP-1 antibody was used to detect the fusion of lysosomes with the plasma membrane, GFP-transfected RPE cells were used to examine the release of GFP from the cytoplasm, and 7-AAD was used to assess cell viability. Subsequently, cells were exposed to USMB (106 cells/mL, 300 kPa peak negative pressure, 1 min treatment duration, and 20 µL/mL Definity microbubbles). Following USMB, the release of the fluorescent markers was examined at 1.5, 11.5, and 21.5 minutes from the start of USMB. The mean fluorescent intensity (MFI) of untreated and USMB treated samples were measured using flow cytometry. USMB increased the extracellular delivery of GFP molecules from the cytoplasm; the MFI in USMB treated GFP-transfected RPE cells decreased by 17% in viable cells and this MFI decreased by 70% in non-viable cells. This could be due to diffusion of GFP through the membrane disruptions induced by USMB. Additionally, the MFI of viable cells stained with LAMP-1 antibody increased by 50% and this increase was 15 folds in the non-viable cells indicating lysosome exocytosis as a mechanism for membrane repair. Furthermore, the MFI of cells loaded with fluorescent transferrin decreased by 22% after USMB treatment in viable cells, indicating a significant increase in transferrin recycling to the cell membrane. However, the increased recycling was not statistically significant

  4. Role of the extracellular matrix during neural crest cell migration.

    Science.gov (United States)

    Perris, R; Perissinotto, D

    2000-07-01

    Once specified to become neural crest (NC), cells occupying the dorsal portion of the neural tube disrupt their cadherin-mediated cell-cell contacts, acquire motile properties, and embark upon an extensive migration through the embryo to reach their ultimate phenotype-specific sites. The understanding of how this movement is regulated is still rather fragmentary due to the complexity of the cellular and molecular interactions involved. An additional intricate aspect of the regulation of NC cell movement is that the timings, modes and patterns of NC cell migration are intimately associated with the concomitant phenotypic diversification that cells undergo during their migratory phase and the fact that these changes modulate the way that moving cells interact with their microenvironment. To date, two interplaying mechanisms appear central for the guidance of the migrating NC cells through the embryo: one involves secreted signalling molecules acting through their cognate protein kinase/phosphatase-type receptors and the other is contributed by the multivalent interactions of the cells with their surrounding extracellular matrix (ECM). The latter ones seem fundamental in light of the central morphogenetic role played by the intracellular signals transduced through the cytoskeleton upon integrin ligation, and the convergence of these signalling cascades with those triggered by cadherins, survival/growth factor receptors, gap junctional communications, and stretch-activated calcium channels. The elucidation of the importance of the ECM during NC cell movement is presently favoured by the augmenting knowledge about the macromolecular structure of the specific ECM assembled during NC development and the functional assaying of its individual constituents via molecular and genetic manipulations. Collectively, these data propose that NC cell migration may be governed by time- and space-dependent alterations in the expression of inhibitory ECM components; the relative ratio

  5. Extracellular KCl effect on organic bound tritium in human cells

    International Nuclear Information System (INIS)

    Gonen, Rafi; Uzi, German; Priel, Esther; Alfassi, Zeev B.

    2008-01-01

    Tritium atoms can replace hydrogen atoms in organic compounds, forming Organic Bound Tritium. Therefore, exposure of the body to tritium may lead to binding of tritium in tissue molecules, retaining it in the body longer than HTO, and causing higher doses. Ignoring this effect when evaluating inner exposures, may lead to under-estimation of tritium exposures. It was published, that tritium bound to some organic molecules has the potential to accumulate in organisms at higher levels as in the surrounding media. In order to investigate this effect and to identify physiological factors, OBT production in human malignant MG-63 osteoblast cells was studied. The purpose of the present work was to investigate the influence of the ionic extracellular potassium concentration on the amount of tritium in cells. Potassium is known as an ionic compound present in the body, which has the potential to cause cells swelling. Therefore, cells were exposed to isotonic and hypotonic media, supplemented with different concentrations of KCl, and the tritium accumulations were determined after incubation with HTO. An increase in the total Organic Bound Tritium production was observed, as well as an increase of the intracellular HTO content when increasing the KCl concentration. (author)

  6. Thermally assisted acoustofluidic separation of extracellular vesicles from cells

    Science.gov (United States)

    Mirtaheri, Elnaz; Dolatmoradi, Ata; Pimentel, Krystine; Bhansali, Shekhar; El-Zahab, Bilal

    2018-02-01

    Extracellular vesicles (EVs) have been gaining increasing attention given their role in communicating information between cells. Composition-based isolation of EVs is particularly of high significance as the proteomic and lipidomic characterization of their cargo could provide valuable clues to the role of EVs in mediating the biology of various conditions. This has, however, proved to be challenging as EVs, despite their abundance, are very small and difficult to be differentiated from the other constituents of host media. In addition, currently available methods like ultracentrifugation and filtration are cumbersome and capable of achieving mostly size-based separations. In this work, we demonstrate the possibility of separating submicron EV-like vesicles from cancer cells using a thermally-assisted acoustophoretic device. In a system composed of MCF-7 breast cancer cells spiked with two different types of same-size vesicles, composition-based isolation of vesicles was shown to be realizable through opposite focusing of the system's components at the node and antinodes of the overlaid ultrasonic standing wave. By proper choice of temperature in the microchannel, we were able to achieve separations with purities exceeding 93%. Furthermore, cells recovered from the channel were shown to be viable after the separation.

  7. Extracellular matrix-derived hydrogels for dental stem cell delivery.

    Science.gov (United States)

    Viswanath, Aiswarya; Vanacker, Julie; Germain, Loïc; Leprince, Julian G; Diogenes, Anibal; Shakesheff, Kevin M; White, Lisa J; des Rieux, Anne

    2017-01-01

    Decellularized mammalian extracellular matrices (ECM) have been widely accepted as an ideal substrate for repair and remodelling of numerous tissues in clinical and pre-clinical studies. Recent studies have demonstrated the ability of ECM scaffolds derived from site-specific homologous tissues to direct cell differentiation. The present study investigated the suitability of hydrogels derived from different source tissues: bone, spinal cord and dentine, as suitable carriers to deliver human apical papilla derived mesenchymal stem cells (SCAP) for spinal cord regeneration. Bone, spinal cord, and dentine ECM hydrogels exhibited distinct structural, mechanical, and biological characteristics. All three hydrogels supported SCAP viability and proliferation. However, only spinal cord and bone derived hydrogels promoted the expression of neural lineage markers. The specific environment of ECM scaffolds significantly affected the differentiation of SCAP to a neural lineage, with stronger responses observed with spinal cord ECM hydrogels, suggesting that site-specific tissues are more likely to facilitate optimal stem cell behavior for constructive spinal cord regeneration. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 319-328, 2017. © 2016 Wiley Periodicals, Inc.

  8. Regulation of pituitary hormones and cell proliferation by components of the extracellular matrix

    Directory of Open Access Journals (Sweden)

    M. Paez-Pereda

    2005-10-01

    Full Text Available The extracellular matrix is a three-dimensional network of proteins, glycosaminoglycans and other macromolecules. It has a structural support function as well as a role in cell adhesion, migration, proliferation, differentiation, and survival. The extracellular matrix conveys signals through membrane receptors called integrins and plays an important role in pituitary physiology and tumorigenesis. There is a differential expression of extracellular matrix components and integrins during the pituitary development in the embryo and during tumorigenesis in the adult. Different extracellular matrix components regulate adrenocorticotropin at the level of the proopiomelanocortin gene transcription. The extracellular matrix also controls the proliferation of adrenocorticotropin-secreting tumor cells. On the other hand, laminin regulates the production of prolactin. Laminin has a dynamic pattern of expression during prolactinoma development with lower levels in the early pituitary hyperplasia and a strong reduction in fully grown prolactinomas. Therefore, the expression of extracellular matrix components plays a role in pituitary tumorigenesis. On the other hand, the remodeling of the extracellular matrix affects pituitary cell proliferation. Matrix metalloproteinase activity is very high in all types of human pituitary adenomas. Matrix metalloproteinase secreted by pituitary cells can release growth factors from the extracellular matrix that, in turn, control pituitary cell proliferation and hormone secretion. In summary, the differential expression of extracellular matrix components, integrins and matrix metalloproteinase contributes to the control of pituitary hormone production and cell proliferation during tumorigenesis.

  9. Extracellular ATP inhibits Schwann cell dedifferentiation and proliferation in an ex vivo model of Wallerian degeneration

    International Nuclear Information System (INIS)

    Shin, Youn Ho; Lee, Seo Jin; Jung, Junyang

    2013-01-01

    Highlights: ► ATP-treated sciatic explants shows the decreased expression of p75NGFR. ► Extracellular ATP inhibits the expression of phospho-ERK1/2. ► Lysosomal exocytosis is involved in Schwann cell dedifferentiation. ► Extracellular ATP blocks Schwann cell proliferation in sciatic explants. -- Abstract: After nerve injury, Schwann cells proliferate and revert to a phenotype that supports nerve regeneration. This phenotype-changing process can be viewed as Schwann cell dedifferentiation. Here, we investigated the role of extracellular ATP in Schwann cell dedifferentiation and proliferation during Wallerian degeneration. Using several markers of Schwann cell dedifferentiation and proliferation in sciatic explants, we found that extracellular ATP inhibits Schwann cell dedifferentiation and proliferation during Wallerian degeneration. Furthermore, the blockage of lysosomal exocytosis in ATP-treated sciatic explants is sufficient to induce Schwann cell dedifferentiation. Together, these findings suggest that ATP-induced lysosomal exocytosis may be involved in Schwann cell dedifferentiation.

  10. Trash or Treasure: extracellular microRNAs and cell-to-cell communication

    Directory of Open Access Journals (Sweden)

    Nobuyoshi eKosaka

    2013-09-01

    Full Text Available Circulating RNAs in human body fluids are promising candidates for diagnostic purposes. However, the biological significance of circulating RNAs remains elusive. Recently, small non-coding RNAs, microRNAs (miRNAs, were isolated from multiple human body fluids, and these circulating miRNAs have been implicated as novel disease biomarkers. Concurrently, miRNAs were also identified in the extracellular space associated with extracellular vesicles (EVs, which are small membrane vesicles secreted from various types of cells. The function of these secreted miRNAs has been revealed in several papers. Circulating miRNAs have been experimentally found to be associated with EVs, however, other types of extracellular miRNAs were also described. This review discusses studies related to extracellular miRNAs, including circulating miRNAs and secreted miRNAs, to highlight the importance of studying not only secreted miRNAs but also circulating miRNAs to determine the contribution of extracellular miRNAs especially in cancer development.

  11. Cell Adhesions: Actin-Based Modules that Mediate Cell-Extracellular Matrix and Cell-Cell Interactions

    Science.gov (United States)

    Bachir, Alexia; Horwitz, Alan Rick; Nelson, W. James; Bianchini, Julie M.

    2018-01-01

    Cell adhesions link cells to the extracellular matrix (ECM) and to each other, and depend on interactions with the actin cytoskeleton. Both cell-ECM and cell-cell adhesion sites contain discrete, yet overlapping functional modules. These modules establish physical association with the actin cytoskeleton, locally modulate actin organization and dynamics, and trigger intracellular signaling pathways. Interplay between these modules generates distinct actin architectures that underlie different stages, types, and functions of cell-ECM and cell-cell adhesions. Actomyosin contractility is required to generate mature, stable adhesions, as well as sense and translate the mechanical properties of the cellular environment to changes in cell organization and behavior. In this chapter we discuss the organization and function of different adhesion modules and how they interact with the actin cytoskeleton. We highlight the molecular mechanisms of mechanotransduction in adhesions, and how adhesion molecules mediate crosstalk between cell-ECM and cell-cell adhesion sites. PMID:28679638

  12. Depressed immune surveillance against cancer: role of deficient T cell: extracellular matrix interactions.

    Science.gov (United States)

    Górski, A; Castronovo, V; Stepień-Sopniewska, B; Grieb, P; Ryba, M; Mrowiec, T; Korczak-Kowalska, G; Wierzbicki, P; Matysiak, W; Dybowska, B

    1994-07-01

    Although T cells infiltrate malignant tumors, the local immune response is usually inefficient and tumors escape destruction. While extracellular matrix proteins strongly costimulate T cell responses in normal individuals, our studies indicate that peripheral blood T cells from cancer patients and tumor infiltrating cells respond poorly or are resistant to stimulative signals mediated by collagen I and IV and fibronectin. Moreover, the adhesive properties of cancer T cells are markedly depressed. Those functional deficiencies are paralleled by variable deficits in integrin and non-integrin T cell receptors for extracellular matrix. Immunotherapy with BCG causes a dramatic but transient increase in T cell: ECM interactions.

  13. Macromolecular crowding directs extracellular matrix organization and mesenchymal stem cell behavior.

    Directory of Open Access Journals (Sweden)

    Adam S Zeiger

    Full Text Available Microenvironments of biological cells are dominated in vivo by macromolecular crowding and resultant excluded volume effects. This feature is absent in dilute in vitro cell culture. Here, we induced macromolecular crowding in vitro by using synthetic macromolecular globules of nm-scale radius at physiological levels of fractional volume occupancy. We quantified the impact of induced crowding on the extracellular and intracellular protein organization of human mesenchymal stem cells (MSCs via immunocytochemistry, atomic force microscopy (AFM, and AFM-enabled nanoindentation. Macromolecular crowding in extracellular culture media directly induced supramolecular assembly and alignment of extracellular matrix proteins deposited by cells, which in turn increased alignment of the intracellular actin cytoskeleton. The resulting cell-matrix reciprocity further affected adhesion, proliferation, and migration behavior of MSCs. Macromolecular crowding can thus aid the design of more physiologically relevant in vitro studies and devices for MSCs and other cells, by increasing the fidelity between materials synthesized by cells in vivo and in vitro.

  14. Macromolecular crowding directs extracellular matrix organization and mesenchymal stem cell behavior.

    Science.gov (United States)

    Zeiger, Adam S; Loe, Felicia C; Li, Ran; Raghunath, Michael; Van Vliet, Krystyn J

    2012-01-01

    Microenvironments of biological cells are dominated in vivo by macromolecular crowding and resultant excluded volume effects. This feature is absent in dilute in vitro cell culture. Here, we induced macromolecular crowding in vitro by using synthetic macromolecular globules of nm-scale radius at physiological levels of fractional volume occupancy. We quantified the impact of induced crowding on the extracellular and intracellular protein organization of human mesenchymal stem cells (MSCs) via immunocytochemistry, atomic force microscopy (AFM), and AFM-enabled nanoindentation. Macromolecular crowding in extracellular culture media directly induced supramolecular assembly and alignment of extracellular matrix proteins deposited by cells, which in turn increased alignment of the intracellular actin cytoskeleton. The resulting cell-matrix reciprocity further affected adhesion, proliferation, and migration behavior of MSCs. Macromolecular crowding can thus aid the design of more physiologically relevant in vitro studies and devices for MSCs and other cells, by increasing the fidelity between materials synthesized by cells in vivo and in vitro.

  15. Protease inhibitors enhance extracellular collagen fibril deposition in human mesenchymal stem cells.

    Science.gov (United States)

    Han, Sejin; Li, Yuk Yin; Chan, Barbara Pui

    2015-10-15

    Collagen is a widely used naturally occurring biomaterial for scaffolding, whereas mesenchymal stem cells (MSCs) represent a promising cell source in tissue engineering and regenerative medicine. It is generally known that cells are able to remodel their environment by simultaneous degradation of the scaffolds and deposition of newly synthesized extracellular matrix. Nevertheless, the interactions between MSCs and collagen biomaterials are poorly known, and the strategies enhancing the extracellular matrix deposition are yet to be defined. In this study, we aim to investigate the fate of collagen when it is in contact with MSCs and hypothesize that protease inhibition will enhance their extracellular deposition of collagen fibrils. Specifically, human MSCs (hMSCs) were exposed to fluorescence-labeled collagen with and without intracellular or extracellular protease inhibitors (or both) before tracing the collagen at both intracellular and extracellular spaces. Collagen were internalized by hMSCs and degraded intracellularly in lysosomes. In the presence of protease inhibitors, both intracellular collagen fibril growth and extracellular deposition of collagen fibrils were enhanced. Moreover, protease inhibitors work synergistically with ascorbic acid, a well-known matrix deposition-enhancing reagent, in further enhancing collagen fibril deposition at the extracellular space. These findings provide a better understanding of the interactions between hMSCs and collagen biomaterials and suggest a method to manipulate matrix remodeling and deposition of hMSCs, contributing to better scaffolding for tissue engineering and regenerative medicine.

  16. miR-200–containing extracellular vesicles promote breast cancer cell metastasis

    Science.gov (United States)

    Le, Minh T.N.; Hamar, Peter; Guo, Changying; Basar, Emre; Perdigão-Henriques, Ricardo; Balaj, Leonora; Lieberman, Judy

    2014-01-01

    Metastasis is associated with poor prognosis in breast cancer patients. Not all cancer cells within a tumor are capable of metastasizing. The microRNA-200 (miR-200) family, which regulates the mesenchymal-to-epithelial transition, is enriched in the serum of patients with metastatic cancers. Ectopic expression of miR-200 can confer metastatic ability to poorly metastatic tumor cells in some settings. Here, we investigated whether metastatic capability could be transferred between metastatic and nonmetastatic cancer cells via extracellular vesicles. miR-200 was secreted in extracellular vesicles from metastatic murine and human breast cancer cell lines, and miR-200 levels were increased in sera of mice bearing metastatic tumors. In culture, murine and human metastatic breast cancer cell extracellular vesicles transferred miR-200 microRNAs to nonmetastatic cells, altering gene expression and promoting mesenchymal-to-epithelial transition. In murine cancer and human xenograft models, miR-200–expressing tumors and extracellular vesicles from these tumors promoted metastasis of otherwise weakly metastatic cells either nearby or at distant sites and conferred to these cells the ability to colonize distant tissues in a miR-200–dependent manner. Together, our results demonstrate that metastatic capability can be transferred by the uptake of extracellular vesicles. PMID:25401471

  17. The Influence of Virus Infection on the Extracellular pH of the Host Cell Detected on Cell Membrane.

    Science.gov (United States)

    Liu, Hengjun; Maruyama, Hisataka; Masuda, Taisuke; Honda, Ayae; Arai, Fumihito

    2016-01-01

    Influenza virus infection can result in changes in the cellular ion levels at 2-3 h post-infection. More H(+) is produced by glycolysis, and the viral M2 proton channel also plays a role in the capture and release of H(+) during both viral entry and egress. Then the cells might regulate the intracellular pH by increasing the export of H(+) from the intracellular compartment. Increased H(+) export could lead indirectly to increased extracellular acidity. To detect changes in extracellular pH of both virus-infected and uninfected cells, pH sensors were synthesized using polystyrene beads (ϕ1 μm) containing Rhodamine B and Fluorescein isothiocyanate (FITC). The fluorescence intensity of FITC can respond to both pH and temperature. So Rhodamine B was also introduced in the sensor for temperature compensation. Then the pH can be measured after temperature compensation. The sensor was adhered to cell membrane for extracellular pH measurement. The results showed that the multiplication of influenza virus in host cell decreased extracellular pH of the host cell by 0.5-0.6 in 4 h after the virus bound to the cell membrane, compared to that in uninfected cells. Immunostaining revealed the presence of viral PB1 protein in the nucleus of virus-bound cells that exhibited extracellular pH changes, but no PB1 protein are detected in virus-unbound cells where the extracellular pH remained constant.

  18. Method for isolation and molecular characterization of extracellular microvesicles released from brain endothelial cells

    Directory of Open Access Journals (Sweden)

    Haqqani Arsalan S

    2013-01-01

    Full Text Available Abstract Background In addition to possessing intracellular vesicles, eukaryotic cells also produce extracellular microvesicles, ranging from 50 to 1000 nm in diameter that are released or shed into the microenvironment under physiological and pathological conditions. These membranous extracellular organelles include both exosomes (originating from internal vesicles of endosomes and ectosomes (originating from direct budding/shedding of plasma membranes. Extracellular microvesicles contain cell-specific collections of proteins, glycoproteins, lipids, nucleic acids and other molecules. These vesicles play important roles in intercellular communication by acting as carrier for essential cell-specific information to target cells. Endothelial cells in the brain form the blood–brain barrier, a specialized interface between the blood and the brain that tightly controls traffic of nutrients and macromolecules between two compartments and interacts closely with other cells forming the neurovascular unit. Therefore, brain endothelial cell extracellular microvesicles could potentially play important roles in ‘externalizing’ brain-specific biomarkers into the blood stream during pathological conditions, in transcytosis of blood-borne molecules into the brain, and in cell-cell communication within the neurovascular unit. Methods To study cell-specific molecular make-up and functions of brain endothelial cell exosomes, methods for isolation of extracellular microvesicles using mass spectrometry-compatible protocols and the characterization of their signature profiles using mass spectrometry -based proteomics were developed. Results A total of 1179 proteins were identified in the isolated extracellular microvesicles from brain endothelial cells. The microvesicles were validated by identification of almost 60 known markers, including Alix, TSG101 and the tetraspanin proteins CD81 and CD9. The surface proteins on isolated microvesicles could potentially

  19. Extracellular ATP reduces HIV-1 transfer from immature dendritic cells to CD4+ T lymphocytes

    Directory of Open Access Journals (Sweden)

    Barat Corinne

    2008-03-01

    Full Text Available Abstract Background Dendritic cells (DCs are considered as key mediators of the early events in human immunodeficiency virus type 1 (HIV-1 infection at mucosal sites. Previous studies have shown that surface-bound virions and/or internalized viruses found in endocytic vacuoles of DCs are efficiently transferred to CD4+ T cells. Extracellular adenosine triphosphate (ATP either secreted or released from necrotic cells induces a distorted maturation of DCs, transiently increases their endocytic capacity and affects their migratory capacity. Knowing that high extracellular ATP concentrations are present in situations of tissue injury and inflammation, we investigated the effect of ATP on HIV-1 transmission from DCs to CD4+ T lymphocytes. Results In this study, we show that extracellular ATP reduces HIV-1 transfer from immature monocyte-derived DCs (iDCs to autologous CD4+ T cells. This observed decrease in viral replication was related to a lower proportion of infected CD4+ T cells following transfer, and was seen with both X4- and R5-tropic isolates of HIV-1. Extracellular ATP had no effect on direct CD4+ T cell infection as well as on productive HIV-1 infection of iDCs. These observations indicate that extracellular ATP affects HIV-1 infection of CD4+ T cells in trans with no effect on de novo virus production by iDCs. Additional experiments suggest that extracellular ATP might modulate the trafficking pathway of internalized virions within iDCs leading to an increased lysosomal degradation, which could be partly responsible for the decreased HIV-1 transmission. Conclusion These results suggest that extracellular ATP can act as a factor controlling HIV-1 propagation.

  20. Casein gene expression in mouse mammary epithelial cell lines: Dependence upon extracellular matrix and cell type

    International Nuclear Information System (INIS)

    Medina, D.; Oborn, C.J.; Li, M.L.; Bissell, M.J.

    1987-01-01

    The COMMA-D mammary cell line exhibits mammary-specific functional differentiation under appropriate conditions in cell culture. The cytologically heterogeneous COMMA-D parental line and the clonal lines DB-1, TA-5, and FA-1 derived from the COMMA-D parent were examined for similar properties of functional differentiation. In monolayer cell culture, the cell lines DB-1, TA-5, FA-1, and MA-4 were examined for expression of mammary-specific and epithelial-specific proteins by an indirect immunofluorescence assay. The clonal cell lines were relatively homogeneous in their respective staining properties and seemed to represent three subpopulations found in the heterogeneous parental COMMA-D lines. None of the four clonal lines appeared to represent myoepithelial cells. The cell lines were examined for expression of β-casein mRNA in the presence or absence of prolactin. The inducibility of β-casein in the COMMA-D cell line was further enhanced by a reconstituted basement membrane preparation enriched in laminin, collagen IV, and proteoglycans. These results support the hypothesis that the functional response of inducible mammary cell populations is a result of interaction among hormones, multiple extracellular matrix components, and specific cell types

  1. Neurotransmitter modulation of extracellular H+ fluxes from isolated retinal horizontal cells of the skate

    Science.gov (United States)

    Molina, Anthony J A; Verzi, Michael P; Birnbaum, Andrea D; Yamoah, Ebenezer N; Hammar, Katherine; Smith, Peter J S; Malchow, Robert Paul

    2004-01-01

    Self-referencing H+-selective microelectrodes were used to measure extracellular H+ fluxes from horizontal cells isolated from the skate retina. A standing H+ flux was detected from quiescent cells, indicating a higher concentration of free hydrogen ions near the extracellular surface of the cell as compared to the surrounding solution. The standing H+ flux was reduced by removal of extracellular sodium or application of 5-(N-ethyl-N-isopropyl) amiloride (EIPA), suggesting activity of a Na+–H+ exchanger. Glutamate decreased H+ flux, lowering the concentration of free hydrogen ions around the cell. AMPA/kainate receptor agonists mimicked the response, and the AMPA/kainate receptor antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) eliminated the effects of glutamate and kainate. Metabotropic glutamate agonists were without effect. Glutamate-induced alterations in H+ flux required extracellular calcium, and were abolished when cells were bathed in an alkaline Ringer solution. Increasing intracellular calcium by photolysis of the caged calcium compound NP-EGTA also altered extracellular H+ flux. Immunocytochemical localization of the plasmalemma Ca2+–H+-ATPase (PMCA pump) revealed intense labelling within the outer plexiform layer and on isolated horizontal cells. Our results suggest that glutamate modulation of H+ flux arises from calcium entry into cells with subsequent activation of the plasmalemma Ca2+–H+-ATPase. These neurotransmitter-induced changes in extracellular pH have the potential to play a modulatory role in synaptic processing in the outer retina. However, our findings argue against the hypothesis that hydrogen ions released by horizontal cells normally act as the inhibitory feedback neurotransmitter onto photoreceptor synaptic terminals to create the surround portion of the centre-surround receptive fields of retinal neurones. PMID:15272044

  2. Adherence of Staphylococci to plastic, mesothelial cells and mesothelial extracellular matrix

    NARCIS (Netherlands)

    Betjes, M. G.; Tuk, C. W.; Struijk, D. G.; Krediet, R. T.; Arisz, L.; Beelen, R. H.

    1992-01-01

    In this study we have investigated whether mesothelial cells (MC) and mesothelial extracellular matrix (ECM) are suitable substrates for the adherence of Staphylococci. Mesothelial cells were isolated from the peritoneal dialysis effluent by making use of their lack of Fc-receptors and capacity to

  3. Extracellular cell stress (heat shock) proteins-immune responses and disease: an overview.

    Science.gov (United States)

    Pockley, A Graham; Henderson, Brian

    2018-01-19

    Extracellular cell stress proteins are highly conserved phylogenetically and have been shown to act as powerful signalling agonists and receptors for selected ligands in several different settings. They also act as immunostimulatory 'danger signals' for the innate and adaptive immune systems. Other studies have shown that cell stress proteins and the induction of immune reactivity to self-cell stress proteins can attenuate disease processes. Some proteins (e.g. Hsp60, Hsp70, gp96) exhibit both inflammatory and anti-inflammatory properties, depending on the context in which they encounter responding immune cells. The burgeoning literature reporting the presence of stress proteins in a range of biological fluids in healthy individuals/non-diseased settings, the association of extracellular stress protein levels with a plethora of clinical and pathological conditions and the selective expression of a membrane form of Hsp70 on cancer cells now supports the concept that extracellular cell stress proteins are involved in maintaining/regulating organismal homeostasis and in disease processes and phenotype. Cell stress proteins, therefore, form a biologically complex extracellular cell stress protein network having diverse biological, homeostatic and immunomodulatory properties, the understanding of which offers exciting opportunities for delivering novel approaches to predict, identify, diagnose, manage and treat disease.This article is part of the theme issue 'Heat shock proteins as modulators and therapeutic targets of chronic disease: an integrated perspective'. © 2017 The Author(s).

  4. A cell-surface-anchored ratiometric fluorescent probe for extracellular pH sensing.

    Science.gov (United States)

    Ke, Guoliang; Zhu, Zhi; Wang, Wei; Zou, Yuan; Guan, Zhichao; Jia, Shasha; Zhang, Huimin; Wu, Xuemeng; Yang, Chaoyong James

    2014-09-10

    Accurate sensing of the extracellular pH is a very important yet challenging task in biological and clinical applications. This paper describes the development of an amphiphilic lipid-DNA molecule as a simple yet useful cell-surface-anchored ratiometric fluorescent probe for extracellular pH sensing. The lipid-DNA probe, which consists of a hydrophobic diacyllipid tail and a hydrophilic DNA strand, is modified with two fluorescent dyes; one is pH-sensitive as pH indicator and the other is pH-insensitive as an internal reference. The lipid-DNA probe showed sensitive and reversible response to pH change in the range of 6.0-8.0, which is suitable for most extracellular studies. In addition, based on simple hydrophobic interactions with the cell membrane, the lipid-DNA probe can be easily anchored on the cell surface with negligible cytotoxicity, excellent stability, and unique ratiometric readout, thus ensuring its accurate sensing of extracellular pH. Finally, this lipid-DNA-based ratiometric pH indicator was successfully used for extracellular pH sensing of cells in 3D culture environment, demonstrating the potential applications of the sensor in biological and medical studies.

  5. The effect of intra- and extracellular GSH depletion on aerobic radiosensitization in three cell lines

    International Nuclear Information System (INIS)

    Clark, E.P.; Epp, E.R.; Morse-Gaudio, M.; Biaglow, J.E.

    1985-01-01

    The effect of changes in the intra- and extracellular glutathione (GSH) concentrations on aerobic radiosensitization was studied in thee cell lines: CHO, V79 and A549. Intracellular GSH was metabolically depleted after the inhibition of GSH synthesis by buthionine sulfoximine (BSO) treatment of attached cell cultures. Extracellular GSH was controlled through the replacement of growth medium with a thiol-free salt solution and, where desired, by the exogenous addition of GSH. Each of the cell lines examined exhibited an enhanced aerobic radioresponse when the intracellular GSH was extensively depleted (GSH < 5% of control after 1.0 mM BSO/24 hr treatment) and the extracellular GSH concentration was zero. However, this enhanced radiosensitivity was eliminated by the addition of exogenous GSH, albeit at a high concentration (5 mM). Most interesting and as yet unexplained is the observation that GSH appears to affect restoration of the control radioresponse without increasing the intracellular GSH concentration

  6. Investigating the role of the extracellular matrix on differentiation of human mesenchymal stem cells and MC3T3 cells

    NARCIS (Netherlands)

    Fernandes, H.A.M.; Dechering, Koen; Someren, Eugene; van Blitterswijk, Clemens; de Boer, Jan

    2008-01-01

    Human mesenchymal stem cells (hMSCs) are a promising cell source for bone tissue engineering, but due to their limited number and donor variation, other cell types are used to answer relevant questions in bone tissue engineering. Since the extracellular matrix (ECM) is a complex entity with

  7. Osteoblasts secrete miRNA-containing extracellular vesicles that enhance expansion of human umbilical cord blood cells

    NARCIS (Netherlands)

    J. Morhayim (Jess); J. van de Peppel (Jeroen); E. Braakman (Eric); Rombouts, E.W.J.C. (Elwin W. J. C.); M.N.D. Ter Borg (Mariëtte N. D.); A. Dudakovic (Amel); H. Chiba (Hideki); B.C.J. van der Eerden (Bram); M.H.G.P. Raaijmakers (Marc H.G.P.); A.J. van Wijnen (André); J.J. Cornelissen (Jan); J.P.T.M. van Leeuwen (Hans)

    2016-01-01

    textabstractOsteolineage cells represent one of the critical bone marrow niche components that support maintenance of hematopoietic stem and progenitor cells (HSPCs). Recent studies demonstrate that extracellular vesicles (EVs) regulate stem cell development via horizontal transfer of bioactive

  8. Protease inhibitors enhance extracellular collagen fibril deposition in human mesenchymal stem cells

    OpenAIRE

    Han, Sejin; Li, Yuk Yin; Chan, Barbara Pui

    2015-01-01

    Introduction Collagen is a widely used naturally occurring biomaterial for scaffolding, whereas mesenchymal stem cells (MSCs) represent a promising cell source in tissue engineering and regenerative medicine. It is generally known that cells are able to remodel their environment by simultaneous degradation of the scaffolds and deposition of newly synthesized extracellular matrix. Nevertheless, the interactions between MSCs and collagen biomaterials are poorly known, and the strategies enhanci...

  9. 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.

  10. Hypoxic stellate cells of pancreatic cancer stroma regulate extracellular matrix fiber organization and cancer cell motility.

    Science.gov (United States)

    Sada, Masafumi; Ohuchida, Kenoki; Horioka, Kohei; Okumura, Takashi; Moriyama, Taiki; Miyasaka, Yoshihiro; Ohtsuka, Takao; Mizumoto, Kazuhiro; Oda, Yoshinao; Nakamura, Masafumi

    2016-03-28

    Desmoplasia and hypoxia in pancreatic cancer mutually affect each other and create a tumor-supportive microenvironment. Here, we show that microenvironment remodeling by hypoxic pancreatic stellate cells (PSCs) promotes cancer cell motility through alteration of extracellular matrix (ECM) fiber architecture. Three-dimensional (3-D) matrices derived from PSCs under hypoxia exhibited highly organized parallel-patterned matrix fibers compared with 3-D matrices derived from PSCs under normoxia, and promoted cancer cell motility by inducing directional migration of cancer cells due to the parallel fiber architecture. Microarray analysis revealed that procollagen-lysine, 2-oxoglutarate 5-dioxygenase 2 (PLOD2) in PSCs was the gene that potentially regulates ECM fiber architecture under hypoxia. Stromal PLOD2 expression in surgical specimens of pancreatic cancer was confirmed by immunohistochemistry. RNA interference-mediated knockdown of PLOD2 in PSCs blocked parallel fiber architecture of 3-D matrices, leading to decreased directional migration of cancer cells within the matrices. In conclusion, these findings indicate that hypoxia-induced PLOD2 expression in PSCs creates a permissive microenvironment for migration of cancer cells through architectural regulation of stromal ECM in pancreatic cancer. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  11. Cellular therapy without cells: extracellular vesicles promote activation of stem cells after irradiation

    International Nuclear Information System (INIS)

    Lange, C.

    2016-01-01

    Mesenchymal stromal cells from the bone marrow (MSC) have been shown to be effective in several cell therapeutic treatments. However, MSC accumulate in lungs after i.v. injection. How do MSC transfer their potential to organs with therapeutic need? We show that released extracellular vesicles (EV) might be playing an active role in this transfer. EV were isolated from MSC supernatant and characterized with flow cytometry, proteomics and next generation sequencing. Our data showed the transfer of RNAs, clustering into several protective gene groups. Besides, we repeatedly detected genomic DNA on vesicles. Using a plant - derived detector gene we showed horizontal DNA transfer via EV. Furthermore, we showed that EV were able to salvage stem/progenitor cells in vitro from radiation suppression. Three selected proteins from proteomics data were examined for stem cell protection after irradiation. EV derived from down-regulated producer MSC showed a substantial loss of protection in irradiated stem cells supporting their relevance for stem cell protection. Finally, we showed that EV after i.v. injection into lethally irradiated animals colocalize within 2-4 hours with hematopoietic stem cells in the bone marrow giving hint to direct protection of stem cells by EV. In conclusion, EV derived from bone marrow MSC were able to transfer several cargo compounds leading potentially to change of the genetic properties. Importantly, EV protect irradiated hematopoietic stem cells, stimulate their recovery and proliferation and rescue lethally irradiated animals long-term. Thus, EV might be an alternative for future cell therapeutic treatment particularly in radiation-based events. (author)

  12. Capillary network formation from dispersed endothelial cells: Influence of cell traction, cell adhesion, and extracellular matrix rigidity

    Science.gov (United States)

    Ramos, João R. D.; Travasso, Rui; Carvalho, João

    2018-01-01

    The formation of a functional vascular network depends on biological, chemical, and physical processes being extremely well coordinated. Among them, the mechanical properties of the extracellular matrix and cell adhesion are fundamental to achieve a functional network of endothelial cells, able to fully cover a required domain. By the use of a Cellular Potts Model and Finite Element Method it is shown that there exists a range of values of endothelial traction forces, cell-cell adhesion, and matrix rigidities where the network can spontaneously be formed, and its properties are characterized. We obtain the analytical relation that the minimum traction force required for cell network formation must obey. This minimum value for the traction force is approximately independent on the considered cell number and cell-cell adhesion. We quantify how these two parameters influence the morphology of the resulting networks (size and number of meshes).

  13. Extracellular matrix in oral squamous cell carcinoma: Friend or foe?

    Directory of Open Access Journals (Sweden)

    Sangeeta R Patankar

    2016-01-01

    Conclusion: The observations of this study revealed altered staining reactions of the collagenous stroma and glycoproteins suggesting that tumor cells may release certain enzymes that play a role in the manipulation of ECM to enhance their own survival.

  14. The influence of virus infection on the extracellular pH of the host cell detected on cell membrane

    Directory of Open Access Journals (Sweden)

    Hengjun Liu

    2016-08-01

    Full Text Available Influenza virus infection can result in changes in the cellular ion levels at 2–3 hours post-infection. More H+ is produced by glycolysis, and the viral M2 proton channel also plays a role in the capture and release of H+ during both viral entry and egress. Then the cells might regulate the intracellular pH by increasing the export of H+ from the intracellular compartment. Increased H+ export could lead indirectly to increased extracellular acidity. To detect changes in extracellular pH of both virus-infected and uninfected cells, pH sensors were synthesized using polystyrene beads (1μm containing Rhodamine B and Fluorescein isothiocyanate (FITC. The fluorescence intensity of FITC can respond to both pH and temperature. So Rhodamine B was also introduced in the sensor for temperature compensation. Then the pH can be measured after temperature compensation. The sensor was adhered to cell membrane for extracellular pH measurement. The results showed that the multiplication of influenza virus in host cell decreased extracellular pH of the host cell by 0.5–0.6 in 4 hours after the virus bound to the cell membrane, compared to that in uninfected cells. Immunostaining revealed the presence of viral PB1 subunits in the nucleus of virus-bound cells that exhibited extracellular pH changes, but no PB1 subunits are detected in virus-unbound cells where the extracellular pH remained constant.

  15. A cell-surface-anchored ratiometric i-motif sensor for extracellular pH detection.

    Science.gov (United States)

    Ying, Le; Xie, Nuli; Yang, Yanjing; Yang, Xiaohai; Zhou, Qifeng; Yin, Bincheng; Huang, Jin; Wang, Kemin

    2016-06-14

    A FRET-based sensor is anchored on the cell surface through streptavidin-biotin interactions. Due to the excellent properties of the pH-sensitive i-motif structure, the sensor can detect extracellular pH with high sensitivity and excellent reversibility.

  16. Measuring Bioenergetics in T Cells Using a Seahorse Extracellular Flux Analyzer

    NARCIS (Netherlands)

    van der Windt, Gerritje J. W.; Chang, Chih-Hao; Pearce, Erika L.

    2016-01-01

    This unit contains several protocols to determine the energy utilization of T cells in real-time using a Seahorse Extracellular Flux Analyzer (http://www.seahorsebio.com). The advantages to using this machine over traditional metabolic assays include the simultaneous measurement of glycolysis and

  17. Electrochemical Detection of Circadian Redox Rhythm in Cyanobacterial Cells via Extracellular Electron Transfer.

    Science.gov (United States)

    Nishio, Koichi; Pornpitra, Tunanunkul; Izawa, Seiichiro; Nishiwaki-Ohkawa, Taeko; Kato, Souichiro; Hashimoto, Kazuhito; Nakanishi, Shuji

    2015-06-01

    Recent research on cellular circadian rhythms suggests that the coupling of transcription-translation feedback loops and intracellular redox oscillations is essential for robust circadian timekeeping. For clarification of the molecular mechanism underlying the circadian rhythm, methods that allow for the dynamic and simultaneous detection of transcription/translation and redox oscillations in living cells are needed. Herein, we report that the cyanobacterial circadian redox rhythm can be electrochemically detected based on extracellular electron transfer (EET), a process in which intracellular electrons are exchanged with an extracellular electrode. As the EET-based method is non-destructive, concurrent detection with transcription/translation rhythm using bioluminescent reporter strains becomes possible. An EET pathway that electrochemically connected the intracellular region of cyanobacterial cells with an extracellular electrode was constructed via a newly synthesized electron mediator with cell membrane permeability. In the presence of the mediator, the open circuit potential of the culture medium exhibited temperature-compensated rhythm with approximately 24 h periodicity. Importantly, such circadian rhythm of the open circuit potential was not observed in the absence of the electron mediator, indicating that the EET process conveys the dynamic information regarding the intracellular redox state to the extracellular electrode. These findings represent the first direct demonstration of the intracellular circadian redox rhythm of cyanobacterial cells. © The Author 2015. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  18. Extracellular histones, cell-free DNA, or nucleosomes: differences in immunostimulation

    NARCIS (Netherlands)

    Marsman, Gerben; Zeerleder, Sacha; Luken, Brenda M.

    2016-01-01

    In inflammation, extensive cell death may occur, which results in the release of chromatin components into the extracellular environment. Individually, the purified chromatin components double stranded (ds)DNA and histones have been demonstrated, both in vitro and in vivo, to display various

  19. Nanoparticle Facilitated Extracellular Electron Transfer in Microbial Fuel Cells

    Science.gov (United States)

    2014-10-13

    harvestingelectrical power directly from waste and renewable biomass and thus represent a promising technology for sustainable energy production.1−5 Central...cell membrane (Figure 3e), serving as a porous semiconducting “ shell ” to facilitate the charge transport at bacteria/electrode or bacteria/bacteria

  20. Extracellular localization of catalase is associated with the transformed state of malignant cells.

    Science.gov (United States)

    Böhm, Britta; Heinzelmann, Sonja; Motz, Manfred; Bauer, Georg

    2015-12-01

    Oncogenic transformation is dependent on activated membrane-associated NADPH oxidase (NOX). However, the resultant extracellular superoxide anions are also driving the NO/peroxynitrite and the HOCl pathway, which eliminates NOX-expressing transformed cells through selective apoptosis induction. Tumor progression is dependent on dominant interference with intercellular apoptosis-inducing ROS signaling through membrane-associated catalase, which decomposes H2O2 and peroxynitrite and oxidizes NO. Particularly, the decomposition of extracellular peroxynitrite strictly requires membrane-associated catalase. We utilized small interfering RNA (siRNA)-mediated knockdown of catalase and neutralizing antibodies directed against the enzyme in combination with challenging H2O2 or peroxynitrite to determine activity and localization of catalase in cells from three distinct steps of multistage oncogenesis. Nontransformed cells did not generate extracellular superoxide anions and only showed intracellular catalase activity. Transformed cells showed superoxide anion-dependent intercellular apoptosis-inducing ROS signaling in the presence of suboptimal catalase activity in their membrane. Tumor cells exhibited tight control of intercellular apoptosis-inducing ROS signaling through a high local concentration of membrane-associated catalase. These data demonstrate that translocation of catalase to the outside of the cell membrane is already associated with the transformation step. A strong local increase in the concentration of membrane-associated catalase is achieved during tumor progression and is controlled by tumor cell-derived H2O2 and by transglutaminase.

  1. Binding and Fusion of Extracellular Vesicles to the Plasma Membrane of Their Cell Targets.

    Science.gov (United States)

    Prada, Ilaria; Meldolesi, Jacopo

    2016-08-09

    Exosomes and ectosomes, extracellular vesicles of two types generated by all cells at multivesicular bodies and the plasma membrane, respectively, play critical roles in physiology and pathology. A key mechanism of their function, analogous for both types of vesicles, is the fusion of their membrane to the plasma membrane of specific target cells, followed by discharge to the cytoplasm of their luminal cargo containing proteins, RNAs, and DNA. Here we summarize the present knowledge about the interactions, binding and fusions of vesicles with the cell plasma membrane. The sequence initiates with dynamic interactions, during which vesicles roll over the plasma membrane, followed by the binding of specific membrane proteins to their cell receptors. Membrane binding is then converted rapidly into fusion by mechanisms analogous to those of retroviruses. Specifically, proteins of the extracellular vesicle membranes are structurally rearranged, and their hydrophobic sequences insert into the target cell plasma membrane which undergoes lipid reorganization, protein restructuring and membrane dimpling. Single fusions are not the only process of vesicle/cell interactions. Upon intracellular reassembly of their luminal cargoes, vesicles can be regenerated, released and fused horizontally to other target cells. Fusions of extracellular vesicles are relevant also for specific therapy processes, now intensely investigated.

  2. Extracellular vesicle-derived protein from Bifidobacterium longum alleviates food allergy through mast cell suppression.

    Science.gov (United States)

    Kim, Jung-Hwan; Jeun, Eun-Ji; Hong, Chun-Pyo; Kim, Seong-Hoon; Jang, Min Seong; Lee, Eun-Jung; Moon, Sook Jin; Yun, Chang Ho; Im, Sin-Hyeog; Jeong, Seok-Geun; Park, Beom-Young; Kim, Kyong-Tai; Seoh, Ju-Young; Kim, Yoon-Keun; Oh, Sung-Jong; Ham, Jun-Sang; Yang, Bo-Gie; Jang, Myoung Ho

    2016-02-01

    The incidence of food allergies has increased dramatically during the last decade. Recently, probiotics have been studied for the prevention and treatment of allergic disease. We examined whether Bifidobacterium longum KACC 91563 and Enterococcus faecalis KACC 91532 have the capacity to suppress food allergies. B longum KACC 91563 and E faecalis KACC 91532 were administered to BALB/c wild-type mice, in which food allergy was induced by using ovalbumin and alum. Food allergy symptoms and various immune responses were assessed. B longum KACC 91563, but not E faecalis KACC 91532, alleviated food allergy symptoms. Extracellular vesicles of B longum KACC 91563 bound specifically to mast cells and induced apoptosis without affecting T-cell immune responses. Furthermore, injection of family 5 extracellular solute-binding protein, a main component of extracellular vesicles, into mice markedly reduced the occurrence of diarrhea in a mouse food allergy model. B longum KACC 91563 induces apoptosis of mast cells specifically and alleviates food allergy symptoms. Accordingly, B longum KACC 91563 and family 5 extracellular solute-binding protein exhibit potential as therapeutic approaches for food allergies. Copyright © 2015 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  3. Effects of extracellular modulation through hypoxia on the glucose metabolism of human breast cancer stem cells

    Science.gov (United States)

    Yustisia, I.; Jusman, S. W. A.; Wanandi, S. I.

    2017-08-01

    Cancer stem cells have been reported to maintain stemness under certain extracellular changes. This study aimed to analyze the effect of extracellular O2 level modulation on the glucose metabolism of human CD24-/CD44+ breast cancer stem cells (BCSCs). The primary BCSCs (CD24-/CD44+ cells) were cultured under hypoxia (1% O2) for 0.5, 4, 6, 24 and 48 hours. After each incubation period, HIF1α, GLUT1 and CA9 expressions, as well as glucose metabolism status, including glucose consumption, lactate production, O2 consumption and extracellular pH (pHe) were analyzed using qRT-PCR, colorimetry, fluorometry, and enzymatic reactions, respectively. Hypoxia caused an increase in HIF1α mRNA expressions and protein levels and shifted the metabolic states to anaerobic glycolysis, as demonstrated by increased glucose consumption and lactate production, as well as decreased O2 consumption and pHe. Furthermore, we demonstrated that GLUT1 and CA9 mRNA expressions simultaneously increased, in line with HIF1α expression. In conclusion, modulation of the extracellular environment of human BCSCs through hypoxia shifedt the metabolic state of BCSCs to anaerobic glycolysis, which might be associated with GLUT1 and CA9 expressions regulated by HIFlα transcription factor.

  4. Electrochemical Quantification of Extracellular Local H2O2 Kinetics Originating from Single Cells.

    Science.gov (United States)

    Bozem, Monika; Knapp, Phillip; Mirčeski, Valentin; Slowik, Ewa J; Bogeski, Ivan; Kappl, Reinhard; Heinemann, Christian; Hoth, Markus

    2017-05-15

    H 2 O 2 is produced by all eukaryotic cells under physiological and pathological conditions. Due to its enormous relevance for cell signaling at low concentrations and antipathogenic function at high concentrations, precise quantification of extracellular local H 2 O 2 concentrations ([H 2 O 2 ]) originating from single cells is required. Using a scanning electrochemical microscope and bare platinum disk ultramicroelectrodes, we established sensitive long-term measurements of extracellular [H 2 O 2 ] kinetics originating from single primary human monocytes (MCs) ex vivo. For the electrochemical techniques square wave voltammetry, cyclic and linear scan voltammetry, and chronoamperometry, detection limits for [H 2 O 2 ] were determined to be 5, 50, and 500 nM, respectively. Following phorbol ester stimulation, local [H 2 O 2 ] 5-8 μm above a single MC increased by 3.4 nM/s within the first 10 min before reaching a plateau. After extracellular addition of H 2 O 2 to an unstimulated MC, the local [H 2 O 2 ] decreased on average by 4.2 nM/s due to degradation processes of the cell. Using the scanning mode of the setup, we found that H 2 O 2 is evenly distributed around the producing cell and can still be detected up to 30 μm away from the cell. The electrochemical single-cell measurements were validated in MC populations using electron spin resonance spectroscopy and the Amplex ® UltraRed assay. Innovation and Conclusion: We demonstrate a highly sensitive, spatially, and temporally resolved electrochemical approach to monitor dynamics of production and degradation processes for H 2 O 2 separately. Local extracellular [H 2 O 2 ] kinetics originating from single cells is quantified in real time. Antioxid. Redox Signal. 00, 000-000.

  5. Emerging roles of extracellular vesicles in the adaptive response of tumour cells to microenvironmental stress

    Directory of Open Access Journals (Sweden)

    Paulina Kucharzewska

    2013-03-01

    Full Text Available Cells are constantly subjected to various types of endogenous and exogenous stressful stimuli, which can cause serious and even permanent damage. The ability of a cell to sense and adapt to environmental alterations is thus vital to maintain tissue homeostasis during development and adult life. Here, we review some of the major phenotypic characteristics of the hostile tumour microenvironment and the emerging roles of extracellular vesicles in these events.

  6. Extracellular vesicle associated long non-coding RNAs functionally enhance cell viability

    Directory of Open Access Journals (Sweden)

    Chris Hewson

    2016-10-01

    Full Text Available Cells communicate with one another to create microenvironments and share resources. One avenue by which cells communicate is through the action of exosomes. Exosomes are extracellular vesicles that are released by one cell and taken up by neighbouring cells. But how exosomes instigate communication between cells has remained largely unknown. We present evidence here that particular long non-coding RNA molecules are preferentially packaged into exosomes. We also find that a specific class of these exosome associated non-coding RNAs functionally modulate cell viability by direct interactions with l-lactate dehydrogenase B (LDHB, high-mobility group protein 17 (HMG-17, and CSF2RB, proteins involved in metabolism, nucleosomal architecture and cell signalling respectively. Knowledge of this endogenous cell to cell pathway, those proteins interacting with exosome associated non-coding transcripts and their interacting domains, could lead to a better understanding of not only cell to cell interactions but also the development of exosome targeted approaches in patient specific cell-based therapies. Keywords: Non-coding RNA, Extracellular RNA, Exosomes, Retroelement, Pseudogene

  7. Recombinant phosphatidylserine-binding nanobodies for targeting of extracellular vesicles to tumor cells : a plug-and-play approach

    NARCIS (Netherlands)

    Kooijmans, Sander A A; Gitz-Francois, Jerney J J M; Schiffelers, Raymond M; Vader, Pieter

    2018-01-01

    Extracellular vesicles (EVs) are increasingly being recognized as candidate drug delivery systems due to their ability to functionally transfer biological cargo between cells. However, manipulation of targeting properties of EVs through engineering of the producer cells can be challenging and

  8. Production of Monascus pigments as extracellular crystals by cell suspension culture.

    Science.gov (United States)

    Lu, Fengling; Liu, Lujie; Huang, Yaolin; Zhang, Xuehong; Wang, Zhilong

    2018-01-01

    It is generally accepted that Monascus pigments are predominantly cell-bound, including both intracellular and surface-bound pigments. This long-term misconception was corrected in the present work. Production of extracellular crystal pigments by submerged culture of Monascus sp. was confirmed by microscopic observation and collection of Monascus pigments from extracellular broth by direct membrane filtration. Following up the new fact, the bioactivity of mycelia as whole-cell biocatalyst for biosynthesis and biodegradation of Monascus pigments had been detailedly examined in both an aqueous solution and a nonionic surfactant micelle aqueous solution. Based on those experimental results, cell suspension culture in an aqueous medium was developed as a novel strategy for accumulation of high concentration of Monascus pigments. Thus, glucose feeding during submerged culture in the aqueous medium was carried out successfully and high orange Monascus pigments concentration of near 4 g/L was achieved.

  9. Label-free imaging of arterial cells and extracellular matrix using a multimodal CARS microscope

    Science.gov (United States)

    Wang, Han-Wei; Le, Thuc T.; Cheng, Ji-Xin

    2008-04-01

    A multimodal nonlinear optical imaging system that integrates coherent anti-Stokes Raman scattering (CARS), sum-frequency generation (SFG), and two-photon excitation fluorescence (TPEF) on the same platform was developed and applied to visualize single cells and extracellular matrix in fresh carotid arteries. CARS signals arising from CH 2-rich membranes allowed visualization of endothelial cells and smooth muscle cells of the arterial wall. Additionally, CARS microscopy allowed vibrational imaging of elastin and collagen fibrils which are also rich in CH 2 bonds. The extracellular matrix organization was further confirmed by TPEF signals arising from elastin's autofluorescence and SFG signals arising from collagen fibrils' non-centrosymmetric structure. Label-free imaging of significant components of arterial tissues suggests the potential application of multimodal nonlinear optical microscopy to monitor onset and progression of arterial diseases.

  10. Extracellular matrix elasticity and topography: material-based cues that affect cell function via conserved mechanisms

    Science.gov (United States)

    Janson, Isaac A.; Putnam, Andrew J.

    2014-01-01

    Chemical, mechanical, and topographic extracellular matrix (ECM) cues have been extensively studied for their influence on cell behavior. These ECM cues alter cell adhesion, cell shape, and cell migration, and activate signal transduction pathways to influence gene expression, proliferation, and differentiation. ECM elasticity and topography, in particular, have emerged as material properties of intense focus based on strong evidence these physical cue can partially dictate stem cell differentiation. Cells generate forces to pull on their adhesive contacts, and these tractional forces appear to be a common element of cells’ responses to both elasticity and topography. This review focuses on recently published work that links ECM topography and mechanics and their influence on differentiation and other cell behaviors, We also highlight signaling pathways typically implicated in mechanotransduction that are (or may be) shared by cells subjected to topographic cues. Finally, we conclude with a brief discussion of the potential implications of these commonalities for cell based therapies and biomaterial design. PMID:24910444

  11. Eosinophilic Otitis Media: the Aftermath of Eosinophil Extracellular Trap Cell Death.

    Science.gov (United States)

    Ueki, Shigeharu; Ohta, Nobuo; Takeda, Masahide; Konno, Yasunori; Hirokawa, Makoto

    2017-05-01

    Eosinophilic otitis media (EOM) is a refractory disease characterized by the accumulation of eosinophils in middle ear effusion and mucosa. We summarize current knowledge regarding the clinical characteristics and management of EOM. Although eosinophil activation in inflamed foci is involved in the pathogenesis of EOM, little is known about the fate of the eosinophils and aftermath of their cell death. We discuss the possibility that eosinophils undergo non-apoptotic cell death that worsens tissue damage and increases effusion viscosity. Unlike chronic otitis media, EOM is strongly associated with an allergic background. Corticosteroids are currently the only effective pharmacological treatment, and surgical intervention is often required. Mucosal eosinophils infiltrate extensively into the middle ear cavity where they are stimulated by locally produced activators including interleukin-5 and eotaxin. The eosinophils undergo cytolysis in the effusion, which represents a major fate of activated eosinophils in vivo. Recent data revealed cytolysis could be renamed as extracellular trap cell death (ETosis). ETosis represents suicidal cell death involving total cell degranulation and development of sticky chromatin structures (extracellular traps (ETs)). The characteristics of eosinophil- and neutrophil-derived ET polymers might contribute to the difference in viscosity of secretions between EOM and common chronic otitis media. The extracellular products remaining after eosinophil ETosis are an important aspect of EOM pathology. The concept of ETosis also has novel implications for potential therapeutic modalities in various eosinophilic disorders.

  12. Arabidopsis GRI is involved in the regulation of cell death induced by extracellular ROS.

    Science.gov (United States)

    Wrzaczek, Michael; Brosché, Mikael; Kollist, Hannes; Kangasjärvi, Jaakko

    2009-03-31

    Reactive oxygen species (ROS) have important functions in plant stress responses and development. In plants, ozone and pathogen infection induce an extracellular oxidative burst that is involved in the regulation of cell death. However, very little is known about how plants can perceive ROS and regulate the initiation and the containment of cell death. We have identified an Arabidopsis thaliana protein, GRIM REAPER (GRI), that is involved in the regulation of cell death induced by extracellular ROS. Plants with an insertion in GRI display an ozone-sensitive phenotype. GRI is an Arabidopsis ortholog of the tobacco flower-specific Stig1 gene. The GRI protein appears to be processed in leaves with a release of an N-terminal fragment of the protein. Infiltration of the N-terminal fragment of the GRI protein into leaves caused cell death in a superoxide- and salicylic acid-dependent manner. Analysis of the extracellular GRI protein yields information on how plants can initiate ROS-induced cell death during stress response and development.

  13. Extracellular histones disarrange vasoactive mediators release through a COX-NOS interaction in human endothelial cells.

    Science.gov (United States)

    Pérez-Cremades, Daniel; Bueno-Betí, Carlos; García-Giménez, José Luis; Ibañez-Cabellos, José Santiago; Hermenegildo, Carlos; Pallardó, Federico V; Novella, Susana

    2017-08-01

    Extracellular histones are mediators of inflammation, tissue injury and organ dysfunction. Interactions between circulating histones and vascular endothelial cells are key events in histone-mediated pathologies. Our aim was to investigate the implication of extracellular histones in the production of the major vasoactive compounds released by human endothelial cells (HUVECs), prostanoids and nitric oxide (NO). HUVEC exposed to increasing concentrations of histones (0.001 to 100 μg/ml) for 4 hrs induced prostacyclin (PGI2) production in a dose-dependent manner and decreased thromboxane A2 (TXA2) release at 100 μg/ml. Extracellular histones raised cyclooxygenase-2 (COX-2) and prostacyclin synthase (PGIS) mRNA and protein expression, decreased COX-1 mRNA levels and did not change thromboxane A2 synthase (TXAS) expression. Moreover, extracellular histones decreased both, eNOS expression and NO production in HUVEC. The impaired NO production was related to COX-2 activity and superoxide production since was reversed after celecoxib (10 μmol/l) and tempol (100 μmol/l) treatments, respectively. In conclusion, our findings suggest that extracellular histones stimulate the release of endothelial-dependent mediators through an up-regulation in COX-2-PGIS-PGI2 pathway which involves a COX-2-dependent superoxide production that decreases the activity of eNOS and the NO production. These effects may contribute to the endothelial cell dysfunction observed in histone-mediated pathologies. © 2017 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  14. Extracellular Ca(2+)-dependent enhancement of cytocidal potency of zoledronic acid in human oral cancer cells.

    Science.gov (United States)

    Inoue, Sayaka; Arai, Naoya; Tomihara, Kei; Takashina, Michinori; Hattori, Yuichi; Noguchi, Makoto

    2015-08-15

    Direct antitumor effects of bisphosphonates (BPs) have been demonstrated in various cancer cells in vitro. However, the effective concentrations of BPs are typically much higher than their clinically relevant concentrations. Oral cancers frequently invade jawbone and may lead to the release of Ca(2+) in primary lesions. We investigated the effects of the combined application of zoledronic acid (ZA) and Ca(2+) on proliferation and apoptosis of oral cancer cells. Human oral cancer cells, breast cancer cells, and colon cancer cells were treated with ZA at a wide range of concentrations in different Ca(2+) concentration environments. Under a standard Ca(2+) concentration (0.6mM), micromolar concentrations of ZA were required to inhibit oral cancer cell proliferation. Increasing extracellular Ca(2+) concentrations greatly enhanced the potency of the ZA cytocidal effect. The ability of Ca(2+) to enhance the cytocidal effects of ZA was negated by the Ca(2+)-selective chelator EGTA. In contrast, the cytocidal effect of ZA was less pronounced in breast and colon cancer cells regardless of whether extracellular Ca(2+) was elevated. In oral cancer cells incubated with 1.6mM Ca(2+), ZA up-regulated mitochondrial Bax expression and increased mitochondrial Ca(2+) uptake. This was associated with decreased mitochondrial membrane potential and increased release of cytochrome c. We suggest that ZA can specifically produce potent cytocidal activity in oral cancer cells in an extracellular Ca(2+)-dependent manner, implying that BPs may be useful for treatment of oral squamous cell carcinoma with jawbone invasion leading to the hypercalcemic state. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Extracellular Nucleotide Hydrolysis in Dermal and Limbal Mesenchymal Stem Cells: A Source of Adenosine Production.

    Science.gov (United States)

    Naasani, Liliana I Sous; Rodrigues, Cristiano; de Campos, Rafael Paschoal; Beckenkamp, Liziane Raquel; Iser, Isabele C; Bertoni, Ana Paula Santin; Wink, Márcia R

    2017-08-01

    Human Limbal (L-MSCs) and Dermal Mesenchymal Stem Cell (D-MSCs) possess many properties that increase their therapeutic potential in ophthalmology and dermatology. It is known that purinergic signaling plays a role in many aspects of mesenchymal stem cells physiology. They release and respond to purinergic ligands, altering proliferation, migration, differentiation, and apoptosis. Therefore, more information on these processes would be crucial for establishing future clinical applications using their differentiation potential, but without undesirable side effects. This study evaluated and compared the expression of ecto-nucleotidases, the enzymatic activity of degradation of extracellular nucleotides and the metabolism of extracellular ATP in D-MSCs and L-MSCs, isolated from discard tissues of human skin and sclerocorneal rims. The D-MSCs and L-MSCs showed a differentiation potential into osteogenic, adipogenic, and chondrogenic lineages and the expression of markers CD105 + , CD44 + , CD14 - , CD34 - , CD45 - , as expected. Both cells hydrolyzed low levels of extracellular ATP and high levels of AMP, leading to adenosine accumulation that can regulate inflammation and tissue repair. These cells expressed mRNA for ENTPD1, 2, 3, 5 and 6, and CD73 that corresponded to the observed enzymatic activities. Thus, considering the degradation of ATP and adenosine production, limbal MSCs are very similar to dermal MSCs, indicating that from the aspect of extracellular nucleotide metabolism L-MSCs are very similar to the characterized D-MSCs. J. Cell. Biochem. 118: 2430-2442, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  16. Extracellular sphingosine-1-phosphate: a novel actor in human glioblastoma stem cell survival.

    Directory of Open Access Journals (Sweden)

    Elena Riccitelli

    Full Text Available Glioblastomas are the most frequent and aggressive intracranial neoplasms in humans, and despite advances and the introduction of the alkylating agent temozolomide in therapy have improved patient survival, resistance mechanisms limit benefits. Recent studies support that glioblastoma stem-like cells (GSCs, a cell subpopulation within the tumour, are involved in the aberrant expansion and therapy resistance properties of glioblastomas, through still unclear mechanisms. Emerging evidence suggests that sphingosine-1-phosphate (S1P a potent onco-promoter able to act as extracellular signal, favours malignant and chemoresistance properties in GSCs. Notwithstanding, the origin of S1P in the GSC environment remains unknown. We investigated S1P metabolism, release, and role in cell survival properties of GSCs isolated from either U87-MG cell line or a primary culture of human glioblastoma. We show that both GSC models, grown as neurospheres and expressing GSC markers, are resistant to temozolomide, despite not expressing the DNA repair protein MGMT, a major contributor to temozolomide-resistance. Pulse experiments with labelled sphingosine revealed that both GSC types are able to rapidly phosphorylate the long-chain base, and that the newly produced S1P is efficiently degraded. Of relevance, we found that S1P was present in GSC extracellular medium, its level being significantly higher than in U87-MG cells, and that the extracellular/intracellular ratio of S1P was about ten-fold higher in GSCs. The activity of sphingosine kinases was undetectable in GSC media, suggesting that mechanisms of S1P transport to the extracellular environment are constitutive in GSCs. In addition we found that an inhibitor of S1P biosynthesis made GSCs sensitive to temozolomide (TMZ, and that exogenous S1P reverted this effect, thus involving extracellular S1P as a GSC survival signal in TMZ resistance. Altogether our data implicate for the first time GSCs as a pivotal source

  17. Myogenic Progenitor Cells Control Extracellular Matrix Production by Fibroblasts during Skeletal Muscle Hypertrophy.

    Science.gov (United States)

    Fry, Christopher S; Kirby, Tyler J; Kosmac, Kate; McCarthy, John J; Peterson, Charlotte A

    2017-01-05

    Satellite cells, the predominant stem cell population in adult skeletal muscle, are activated in response to hypertrophic stimuli and give rise to myogenic progenitor cells (MPCs) within the extracellular matrix (ECM) that surrounds myofibers. This ECM is composed largely of collagens secreted by interstitial fibrogenic cells, which influence satellite cell activity and muscle repair during hypertrophy and aging. Here we show that MPCs interact with interstitial fibrogenic cells to ensure proper ECM deposition and optimal muscle remodeling in response to hypertrophic stimuli. MPC-dependent ECM remodeling during the first week of a growth stimulus is sufficient to ensure long-term myofiber hypertrophy. MPCs secrete exosomes containing miR-206, which represses Rrbp1, a master regulator of collagen biosynthesis, in fibrogenic cells to prevent excessive ECM deposition. These findings provide insights into how skeletal stem and progenitor cells interact with other cell types to actively regulate their extracellular environments for tissue maintenance and adaptation. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Analysis of the interaction of extracellular matrix and phenotype of bladder cancer cells

    International Nuclear Information System (INIS)

    Dozmorov, Mikhail G; Kyker, Kimberly D; Saban, Ricardo; Knowlton, Nicholas; Dozmorov, Igor; Centola, Michael B; Hurst, Robert E

    2006-01-01

    The extracellular matrix has a major effect upon the malignant properties of bladder cancer cells both in vitro in 3-dimensional culture and in vivo. Comparing gene expression of several bladder cancer cells lines grown under permissive and suppressive conditions in 3-dimensional growth on cancer-derived and normal-derived basement membrane gels respectively and on plastic in conventional tissue culture provides a model system for investigating the interaction of malignancy and extracellular matrix. Understanding how the extracellular matrix affects the phenotype of bladder cancer cells may provide important clues to identify new markers or targets for therapy. Five bladder cancer cell lines and one immortalized, but non-tumorigenic, urothelial line were grown on Matrigel, a cancer-derived ECM, on SISgel, a normal-derived ECM, and on plastic, where the only ECM is derived from the cells themselves. The transcriptomes were analyzed on an array of 1186 well-annotated cancer derived cDNAs containing most of the major pathways for malignancy. Hypervariable genes expressing more variability across cell lines than a set expressing technical variability were analyzed further. Expression values were clustered, and to identify genes most likely to represent biological factors, statistically over-represented ontologies and transcriptional regulatory elements were identified. Approximately 400 of the 1186 total genes were expressed 2 SD above background. Approximately 100 genes were hypervariable in cells grown on each ECM, but the pattern was different in each case. A core of 20 were identified as hypervariable under all 3 growth conditions, and 33 were hypervariable on both SISgel and Matrigel, but not on plastic. Clustering of the hypervariable genes showed very different patterns for the same 6 cell types on the different ECM. Even when loss of cell cycle regulation was identified, different genes were involved, depending on the ECM. Under the most permissive conditions

  19. Stress-induced ECM alteration modulates cellular microRNAs that feedback to readjust the extracellular environment and cell behaviour

    Directory of Open Access Journals (Sweden)

    Halyna R Shcherbata

    2013-12-01

    Full Text Available The extracellular environment is a complex entity comprising of the extracellular matrix (ECM and regulatory molecules. It is highly dynamic and under cell-extrinsic stress, transmits the stressed organism’s state to each individual ECM-connected cell. microRNAs (miRNAs are regulatory molecules involved in virtually all the processes in the cell, especially under stress. In this review, we analyse how microRNA expression is regulated downstream of various signal transduction pathways induced by changes in the extracellular environment. In particular, we focus on the muscular dystrophy-associated cell adhesion molecule dystroglycan capable of signal transduction. Then we show how exactly the same miRNAs feedback to regulate the extracellular environment. The ultimate goal of this bi-directional signal transduction process is to change cell behaviour under cell-extrinsic stress in order to respond to it accordingly.

  20. Delivery of viral vectors to tumor cells: extracellular transport, systemic distribution, and strategies for improvement.

    Science.gov (United States)

    Wang, Yong; Yuan, Fan

    2006-01-01

    It is a challenge to deliver therapeutic genes to tumor cells using viral vectors because (i) the size of these vectors are close to or larger than the space between fibers in extracellular matrix and (ii) viral proteins are potentially toxic in normal tissues. In general, gene delivery is hindered by various physiological barriers to virus transport from the site of injection to the nucleus of tumor cells and is limited by normal tissue tolerance of toxicity determined by local concentrations of transgene products and viral proteins. To illustrate the obstacles encountered in the delivery and yet limit the scope of discussion, this review focuses only on extracellular transport in solid tumors and distribution of viral vectors in normal organs after they are injected intravenously or intratumorally. This review also discusses current strategies for improving intratumoral transport and specificity of viral vectors.

  1. Evaluation of viability and proliferative activity of human urothelial cells cultured onto xenogenic tissue-engineered extracellular matrices.

    LENUS (Irish Health Repository)

    Davis, Niall F

    2011-04-01

    To evaluate the viability and proliferative activity of human urothelial cells (HUCs) cultured on tissue-engineered extracellular matrix scaffolds and to assess the potential of extracellular matrixes to support the growth of HUCs in their expected in vivo urine environment.

  2. Suppression of ICE and Apoptosis in Mammary Epithelial Cells by Extracellular Matrix

    Energy Technology Data Exchange (ETDEWEB)

    Boudreau, Nancy; Sympson, C. J.; Werb, Zena; Bissell, Mina J.

    1994-12-01

    Apoptosis (programmed cell death) plays a major role in development and tissue regeneration. Basement membrane extracellular matrix (ECM), but not fibronectin or collagen, was shown to suppress apoptosis of mammary epithelial cells in tissue culture and in vivo. Apoptosis was induced by antibodies to beta 1 integrins or by overexpression of stromelysin-1, which degrades ECM. Expression of interleukin-1 beta converting enzyme (ICE) correlated with the loss of ECM, and inhibitors of ICE activity prevented apoptosis. These results suggest that ECM regulates apoptosis in mammary epithelial cells through an integrin-dependent negative regulation of ICE expression.

  3. Extracellular creatine regulates creatine transport in rat and human muscle cells.

    OpenAIRE

    Loike, J D; Zalutsky, D L; Kaback, E; Miranda, A F; Silverstein, S C

    1988-01-01

    Muscle cells do not synthesize creatine; they take up exogenous creatine by specific Na+-dependent plasma membrane transporters. We found that extracellular creatine regulates the level of expression of these creatine transporters in L6 rat muscle cells. L6 myoblasts maintained for 24 hr in medium containing 1 mM creatine exhibited 1/3rd of the creatine transport activity of cells maintained for 24 hr in medium without creatine. Down-regulation of creatine transport was partially reversed whe...

  4. Effects of extracellular calcium on calcium transport during hyperthermia of tumor cells.

    Science.gov (United States)

    Anghileri, L J; Marcha, C; Crone-Escanyé, M C; Robert, J

    1985-08-01

    The effects of different concentrations of extracellular ion calcium on the transport of calcium by tumor cells have been studied by means of the uptake of radiocalcium. Tumor cells incubated at 45 degrees C take up 4-10 times the amount of radioactivity incorporated by cells incubated at 37 degrees C. The difference is still greater (up to 100 times) for the intracellular incorporation as assessed by elimination of the membrane-bound calcium by EGTA treatment. The possible mechanisms involved in this differential behavior are discussed.

  5. Simple and high yielding method for preparing tissue specific extracellular matrix coatings for cell culture.

    Science.gov (United States)

    DeQuach, Jessica A; Mezzano, Valeria; Miglani, Amar; Lange, Stephan; Keller, Gordon M; Sheikh, Farah; Christman, Karen L

    2010-09-27

    The native extracellular matrix (ECM) consists of a highly complex, tissue-specific network of proteins and polysaccharides, which help regulate many cellular functions. Despite the complex nature of the ECM, in vitro cell-based studies traditionally assess cell behavior on single ECM component substrates, which do not adequately mimic the in vivo extracellular milieu. We present a simple approach for developing naturally derived ECM coatings for cell culture that provide important tissue-specific cues unlike traditional cell culture coatings, thereby enabling the maturation of committed C2C12 skeletal myoblast progenitors and human embryonic stem cells differentiated into cardiomyocytes. Here we show that natural muscle-specific coatings can (i) be derived from decellularized, solubilized adult porcine muscle, (ii) contain a complex mixture of ECM components including polysaccharides, (iii) adsorb onto tissue culture plastic and (iv) promote cell maturation of committed muscle progenitor and stem cells. This versatile method can create tissue-specific ECM coatings, which offer a promising platform for cell culture to more closely mimic the mature in vivo ECM microenvironment.

  6. Recruitment of dental pulp cells by dentine and pulp extracellular matrix components.

    Science.gov (United States)

    Smith, J G; Smith, A J; Shelton, R M; Cooper, P R

    2012-11-01

    The present study aimed to determine whether dentine tissue and preparations of extracellular matrix (ECM) from pulp (pECM) and dentine (dECM), and breakdown products, influenced pulp cell migration. Chemotaxis transwell and agarose spot assays demonstrated that both dentine and pulp ECM molecules acted as chemoattractants for primary pulp cells. Chemoattractant activities of dECM and pECM were enhanced when subjected to acid and enzymatic breakdown, respectively. This enhanced activity following physiologically relevant breakdown may be pertinent to the disease environment. Pulp cell migration in response to dental ECMs was dependent on an active rho pathway. Recruited cells exhibited increased stem cell marker expression indicating that dental ECMs and their breakdown products selectively attract progenitor cells that contribute to repair processes. In conclusion, combined these results indicate that ECM molecules contribute to cell recruitment necessary for regeneration of the dentine-pulp complex after injury. Copyright © 2012 Elsevier Inc. All rights reserved.

  7. Mechanisms of redox metabolism and cancer cell survival during extracellular matrix detachment.

    Science.gov (United States)

    Hawk, Mark A; Schafer, Zachary T

    2018-01-16

    Non-transformed cells that become detached from the extracellular matrix (ECM) undergo dysregulation of redox homeostasis and cell death. In contrast, cancer cells often acquire the ability to mitigate programmed cell death pathways and recalibrate the redox balance to survive after ECM detachment, facilitating metastatic dissemination. Accordingly, recent studies of the mechanisms by which cancer cells overcome ECM detachment-induced metabolic alterations have focused on mechanisms in redox homeostasis. The insights into these mechanisms may inform the development of therapeutics that manipulate redox homeostasis to eliminate ECM-detached cancer cells. Here, we review how ECM-detached cancer cells balance redox metabolism for survival. Published under license by The American Society for Biochemistry and Molecular Biology, Inc.

  8. Artificial extracellular matrix for embryonic stem cell cultures: a new frontier of nanobiomaterials

    Directory of Open Access Journals (Sweden)

    Md Amranul Haque, Masato Nagaoka, Bayar Hexig and Toshihiro Akaike

    2010-01-01

    Full Text Available Nanobiomaterials can play a central role in regenerative medicine and tissue engineering by facilitating cellular behavior and function, such as those where extracellular matrices (ECMs direct embryonic stem (ES cell morphogenesis, proliferation, differentiation and apoptosis. However, controlling ES cell proliferation and differentiation using matrices from natural sources is still challenging due to complex and heterogeneous culture conditions. Moreover, the systemic investigation of the regulation of self-renewal and differentiation to lineage specific cells depends on the use of defined and stress-free culture conditions. Both goals can be achieved by the development of biomaterial design targeting ECM or growth factors for ES cell culture. This targeted application will benefit from expansion of ES cells for transplantation, as well as the production of a specific differentiated cell type either by controlling the differentiation in a very specific pathway or by elimination of undesirable cell types.

  9. Artificial extracellular matrix for embryonic stem cell cultures: a new frontier of nanobiomaterials

    International Nuclear Information System (INIS)

    Haque, Md Amranul; Nagaoka, Masato; Hexig, Bayar; Akaike, Toshihiro

    2010-01-01

    Nanobiomaterials can play a central role in regenerative medicine and tissue engineering by facilitating cellular behavior and function, such as those where extracellular matrices (ECMs) direct embryonic stem (ES) cell morphogenesis, proliferation, differentiation and apoptosis. However, controlling ES cell proliferation and differentiation using matrices from natural sources is still challenging due to complex and heterogeneous culture conditions. Moreover, the systemic investigation of the regulation of self-renewal and differentiation to lineage specific cells depends on the use of defined and stress-free culture conditions. Both goals can be achieved by the development of biomaterial design targeting ECM or growth factors for ES cell culture. This targeted application will benefit from expansion of ES cells for transplantation, as well as the production of a specific differentiated cell type either by controlling the differentiation in a very specific pathway or by elimination of undesirable cell types. (topical review)

  10. Cell-mediated fibre recruitment drives extracellular matrix mechanosensing in engineered fibrillar microenvironments

    Science.gov (United States)

    Baker, Brendon M.; Trappmann, Britta; Wang, William Y.; Sakar, Mahmut S.; Kim, Iris L.; Shenoy, Vivek B.; Burdick, Jason A.; Chen, Christopher S.

    2015-12-01

    To investigate how cells sense stiffness in settings structurally similar to native extracellular matrices, we designed a synthetic fibrous material with tunable mechanics and user-defined architecture. In contrast to flat hydrogel surfaces, these fibrous materials recapitulated cell-matrix interactions observed with collagen matrices including stellate cell morphologies, cell-mediated realignment of fibres, and bulk contraction of the material. Increasing the stiffness of flat hydrogel surfaces induced mesenchymal stem cell spreading and proliferation; however, increasing fibre stiffness instead suppressed spreading and proliferation for certain network architectures. Lower fibre stiffness permitted active cellular forces to recruit nearby fibres, dynamically increasing ligand density at the cell surface and promoting the formation of focal adhesions and related signalling. These studies demonstrate a departure from the well-described relationship between material stiffness and spreading established with hydrogel surfaces, and introduce fibre recruitment as a previously undescribed mechanism by which cells probe and respond to mechanics in fibrillar matrices.

  11. TOPICAL REVIEW: Artificial extracellular matrix for embryonic stem cell cultures: a new frontier of nanobiomaterials

    Science.gov (United States)

    Amranul Haque, Md; Nagaoka, Masato; Hexig, Bayar; Akaike, Toshihiro

    2010-02-01

    Nanobiomaterials can play a central role in regenerative medicine and tissue engineering by facilitating cellular behavior and function, such as those where extracellular matrices (ECMs) direct embryonic stem (ES) cell morphogenesis, proliferation, differentiation and apoptosis. However, controlling ES cell proliferation and differentiation using matrices from natural sources is still challenging due to complex and heterogeneous culture conditions. Moreover, the systemic investigation of the regulation of self-renewal and differentiation to lineage specific cells depends on the use of defined and stress-free culture conditions. Both goals can be achieved by the development of biomaterial design targeting ECM or growth factors for ES cell culture. This targeted application will benefit from expansion of ES cells for transplantation, as well as the production of a specific differentiated cell type either by controlling the differentiation in a very specific pathway or by elimination of undesirable cell types.

  12. The planar cell polarity protein VANGL2 coordinates remodeling of the extracellular matrix.

    Science.gov (United States)

    Williams, B Blairanne; Mundell, Nathan; Dunlap, Julie; Jessen, Jason

    2012-07-01

    Understanding how planar cell polarity (PCP) is established, maintained, and coordinated in migrating cell populations is an important area of research with implications for both embryonic morphogenesis and tumor cell invasion. We recently reported that the PCP protein Vang-like 2 (VANGL2) regulates the endocytosis and cell surface level of membrane type-1 matrix metalloproteinase (MMP14 or MT1-MMP). Here, we further discuss these findings in terms of extracellular matrix (ECM) remodeling, cell migration, and zebrafish gastrulation. We also demonstrate that VANGL2 function impacts the focal degradation of ECM by human cancer cells including the formation or stability of invadopodia. Together, our findings implicate MMP14 as a downstream effector of VANGL2 signaling and suggest a model whereby the regulation of pericellular proteolysis is a fundamental aspect of PCP in migrating cells.

  13. Mechanical phenotyping of cells and extracellular matrix as grade and stage markers of lung tumor tissues.

    Science.gov (United States)

    Panzetta, Valeria; Musella, Ida; Rapa, Ida; Volante, Marco; Netti, Paolo A; Fusco, Sabato

    2017-07-15

    The mechanical cross-talk between cells and the extra-cellular matrix (ECM) regulates the properties, functions and healthiness of the tissues. When this is disturbed it changes the mechanical state of the tissue components, singularly or together, and cancer, along with other diseases, may start and progress. However, the bi-univocal mechanical interplay between cells and the ECM is still not properly understood. In this study we show how a microrheology technique gives us the opportunity to evaluate the mechanics of cells and the ECM at the same time. The mechanical phenotyping was performed on the surgically removed tissues of 10 patients affected by adenocarcinoma of the lung. A correlation between the mechanics and the grade and stage of the tumor was reported and compared to the mechanical characteristics of the healthy tissue. Our findings suggest a sort of asymmetric modification of the mechanical properties of the cells and the extra-cellular matrix in the tumor, being the more compliant cell even though it resides in a stiffer matrix. Overall, the simultaneous mechanical characterization of the tissues constituents (cells and ECM) provided new support for diagnosis and offered alternative points of analysis for cancer mechanobiology. When the integrity of the mechanical cross-talk between cells and the extra-cellular matrix is disturbed cancer, along with other diseases, may initiate and progress. Here, we show how a new technique gives the opportunity to evaluate the mechanics of cells and the ECM at the same time. It was applied on surgically removed tissues of 10 patients affected by adenocarcinoma of the lung and a correlation between the mechanics and the grade and stage of the tumor was reported and compared to the mechanical characteristics of the healthy tissue. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  14. Extracellular matrix of smooth muscle cells: interaction of collagen type V with heparan sulfate proteoglycan

    International Nuclear Information System (INIS)

    Gay, S.; Hoeoek, M.; Gay, R.E.; Magargal, W.W.; Reynertson, R.H.

    1986-01-01

    Alteration in the extracellular matrix produced by smooth muscle cells may play a role in the development of atherosclerotic lesions. Consequently the authors have initiated studies on the structural organization of the extracellular matrix produced by cultured smooth muscle cells. Immunohisotological examination of this matrix using well-characterized mono- and polyclonal antibodies showed a partial codistribution of heparan sulfate (HS) proteoglycans with a number of different matrix components including collagen types I, III, IV, V and VI, laminin and fibronectin. Subsequent binding studies between isolated matrix proteins and HS showed that the polysaccharide interacts strongly with type V collagen and to a lesser extent with fibronectin as well as collagen types III and VI. The interaction between type V and HS was readily inhibited by heparin and highly sulfated HS but not be dermatan sulfate, chondroitin sulfate or HS with a low sulfate content. Furthermore, [ 35 S]-HS proteoglycans isolated from cultured smooth muscle cells could be adsorbed on a column of sepharose conjugated with native type V collagen and eluted in a salt gradient. Hence, the interaction between type V and HS may play a major part in stabilizing the extracellular matrix of the vessel wall

  15. Undersulfation of proteoglycans and proteins alter C6 glioma cells proliferation, adhesion and extracellular matrix organization.

    Science.gov (United States)

    Mendes de Aguiar, Claudia B N; Garcez, Ricardo Castilho; Alvarez-Silva, Marcio; Trentin, Andréa Gonçalves

    2002-11-01

    Proteoglycans are considered to be important molecule in cell-microenvironment interactions. They are overexpressed in neoplastic cells modifying their growth and migration in hosts. In this work we verified that undersulfation of proteoglycans and other sulfated molecules, induced by sodium chlorate treatment, inhibited C6 glioma cells proliferation in a dose-dependent way. This effect was restored by the addition of exogenous heparin. We could not detect significant cell mortality in our culture condition. The treatment also impaired in a dose-dependent manner, C6 cell adhesion to extracellular matrix (ECM) proteins (collagen IV, laminin and fibronectin). In addition, sodium chlorate treatment altered C6 glioma cell morphology, from the fibroblast-like to a more rounded one. This effect was accompanied by increased synthesis of fibronectin and alterations in its extracellular network organization. However, we could not observe modifications on laminin organization and synthesis. The results suggest an important connection between sulfation degree with important tumor functions, such as proliferation and adhesion. We suggest that proteoglycans may modulate the glioma microenvironment network during tumor cell progression and invasion.

  16. The ECM-Cell Interaction of Cartilage Extracellular Matrix on Chondrocytes

    Directory of Open Access Journals (Sweden)

    Yue Gao

    2014-01-01

    Full Text Available Cartilage extracellular matrix (ECM is composed primarily of the network type II collagen (COLII and an interlocking mesh of fibrous proteins and proteoglycans (PGs, hyaluronic acid (HA, and chondroitin sulfate (CS. Articular cartilage ECM plays a crucial role in regulating chondrocyte metabolism and functions, such as organized cytoskeleton through integrin-mediated signaling via cell-matrix interaction. Cell signaling through integrins regulates several chondrocyte functions, including differentiation, metabolism, matrix remodeling, responses to mechanical stimulation, and cell survival. The major signaling pathways that regulate chondrogenesis have been identified as wnt signal, nitric oxide (NO signal, protein kinase C (PKC, and retinoic acid (RA signal. Integrins are a large family of molecules that are central regulators in multicellular biology. They orchestrate cell-cell and cell-matrix adhesive interactions from embryonic development to mature tissue function. In this review, we emphasize the signaling molecule effect and the biomechanics effect of cartilage ECM on chondrogenesis.

  17. Extracellular matrix of dental pulp stem cells: Applications in pulp tissue engineering using somatic MSCs

    Directory of Open Access Journals (Sweden)

    Sriram eRavindran

    2014-01-01

    Full Text Available Dental Caries affects approximately 90% of the world’s population. At present, the clinical treatment for dental caries is root canal therapy. This treatment results in loss of tooth sensitivity and vitality. Tissue engineering can potentially solve this problem by enabling regeneration of a functional pulp tissue. Dental pulp stem cells (DPSCs have been shown to be an excellent source for pulp regeneration. However, limited availability of these cells hinders its potential for clinical translation. We have investigated the possibility of using somatic mesenchymal stem cells from other sources for dental pulp tissue regeneration using a biomimetic dental pulp extracellular matrix (ECM incorporated scaffold. Human periodontal ligament stem cells (PDLSCs and human bone marrow stromal cells (HMSCs were investigated for their ability to differentiate towards an odontogenic lineage. In vitro real-time PCR results coupled with histological and immunohistochemical examination of the explanted tissues confirmed the ability of PDLSCs and HMSCs to form a vascularized pulp-like tissue. These findings indicate that the dental pulp stem derived ECM scaffold stimulated odontogenic differentiation of PDLSCs and HMSCs without the need for exogenous addition of growth and differentiation factors. This study represents a translational perspective toward possible therapeutic application of using a combination of somatic stem cells and extracellular matrix for pulp regeneration.

  18. Extracellular Trapping of Soil Contaminants by Root Border Cells: New Insights into Plant Defense

    Directory of Open Access Journals (Sweden)

    Martha C. Hawes

    2016-01-01

    Full Text Available Soil and water pollution by metals and other toxic chemicals is difficult to measure and control, and, as such, presents an ongoing global threat to sustainable agriculture and human health. Efforts to remove contaminants by plant-mediated pathways, or “phytoremediation”, though widely studied, have failed to yield consistent, predictable removal of biological and chemical contaminants. Emerging research has revealed that one major limitation to using plants to clean up the environment is that plants are programmed to protect themselves: Like white blood cells in animals, border cells released from plant root tips carry out an extracellular trapping process to neutralize threats and prevent injury to the host. Variability in border cell trapping has been found to be correlated with variation in sensitivity of roots to aluminum, and removal of border cell results in increased Al uptake into the root tip. Studies now have implicated border cells in responses of diverse plant roots to a range of heavy metals, including arsenic, copper, cadmium, lead, mercury, iron, and zinc. A better understanding of border cell extracellular traps and their role in preventing toxin uptake may facilitate efforts to use plants as a nondestructive approach to neutralize environmental threats.

  19. The extracellular matrix deposited by asthmatic airway smooth muscle cells in a resting state reflects a healthy matrix

    NARCIS (Netherlands)

    Harkness, Louise; Ashton, Anthony; Burgess, Janette

    2015-01-01

    Introduction: The remodelled asthmatic airway features an altered extracellular matrix (ECM) & increased vasculature. Previous studies found asthmatic (A) airway smooth muscle cells (ASMCs) to deposit an ECM with enhanced bioactivity. These studies however investigated ECM deposited in the presence

  20. Extracellular peptidase hunting for improvement of protein production in plant cells and roots

    Directory of Open Access Journals (Sweden)

    Jérôme eLallemand

    2015-02-01

    Full Text Available Plant-based recombinant protein production systems have gained an extensive interest over the past few years, because of their reduced cost and relative safety. Although the first products are now reaching the market, progress are still needed to improve plant hosts and strategies for biopharming. Targeting recombinant proteins toward the extracellular space offers several advantages in terms of protein folding and purification, but degradation events are observed, due to endogenous peptidases. This paper focuses on the analysis of extracellular proteolytic activities in two production systems: cell cultures and root-secretion (rhizosecretion, in Arabidopsis thaliana and Nicotiana tabacum. Proteolytic activities of extracellular proteomes (secretomes were evaluated in vitro against two substrate proteins: bovine serum albumin (BSA and human serum immunoglobulins G (hIgGs. Both targets were found to be degraded by the secretomes, BSA being more prone to proteolysis than hIgGs. The analysis of the proteolysis pH-dependence showed that target degradation was mainly dependent upon the production system: rhizosecretomes contained more peptidase activity than extracellular medium of cell suspensions, whereas variations due to plant species were smaller. Using class-specific peptidase inhibitors, serine and metallopeptidases were found to be responsible for degradation of both substrates. An in-depth in silico analysis of genomic and transcriptomic data from Arabidopsis was then performed and led to the identification of a limited number of serine and metallo-peptidases that are consistently expressed in both production systems. These peptidases should be prime candidates for further improvement of plant hosts by targeted silencing.

  1. Single Cell Responses to Spatially Controlled Photosensitized Production of Extracellular Singlet Oxygen

    DEFF Research Database (Denmark)

    Pedersen, Brian Wett; Sinks, Louise E.; Breitenbach, Thomas

    2011-01-01

    The response of individual HeLa cells to extracellularly produced singlet oxygen was examined. The spatial domain of singlet oxygen production was controlled using the combination of a membrane-impermeable Pd porphyrin-dendrimer, which served as a photosensitizer, and a focused laser, which served...... to localize the sensitized production of singlet oxygen. Cells in close proximity to the domain of singlet oxygen production showed morphological changes commonly associated with necrotic cell death. The elapsed post-irradiation “waiting period” before necrosis became apparent depended on (a) the distance...... between the cell membrane and the domain irradiated, (b) the incident laser fluence and, as such, the initial concentration of singlet oxygen produced, and (c) the lifetime of singlet oxygen. The data imply that singlet oxygen plays a key role in this process of light-induced cell death. The approach...

  2. How cancer cells dictate their microenvironment: present roles of extracellular vesicles.

    Science.gov (United States)

    Naito, Yutaka; Yoshioka, Yusuke; Yamamoto, Yusuke; Ochiya, Takahiro

    2017-02-01

    Intercellular communication plays an important role in cancer initiation and progression through secretory molecules, including growth factors and cytokines. Recent advances have revealed that small membrane vesicles, termed extracellular vesicles (EVs), served as a regulatory agent in the intercellular communication of cancer. EVs enable the transfer of functional molecules, including proteins, mRNA and microRNAs (miRNAs), into recipient cells. Cancer cells utilize EVs to dictate the unique phenotype of surrounding cells, thereby promoting cancer progression. Against such "education" by cancer cells, non-tumoral cells suppress cancer initiation and progression via EVs. Therefore, researchers consider EVs to be important cues to clarify the molecular mechanisms of cancer biology. Understanding the functions of EVs in cancer progression is an important aspect of cancer biology that has not been previously elucidated. In this review, we summarize experimental data that indicate the pivotal roles of EVs in cancer progression.

  3. Extracellular acidosis activates ASIC-like channels in freshly isolated cerebral artery smooth muscle cells.

    Science.gov (United States)

    Chung, Wen-Shuo; Farley, Jerry M; Swenson, Alyssa; Barnard, John M; Hamilton, Gina; Chiposi, Rumbidzayi; Drummond, Heather A

    2010-05-01

    Recent studies suggest that certain acid-sensing ion channels (ASIC) are expressed in vascular smooth muscle cells (VSMCs) and are required for VSMC functions. However, electrophysiological evidence of ASIC channels in VSMCs is lacking. The purpose of this study was to test the hypothesis that isolated cerebral artery VSMCs express ASIC-like channels. To address this hypothesis, we used RT-PCR, Western blotting, immunolabeling, and conventional whole cell patch-clamp technique. We found extracellular H(+)-induced inward currents in 46% of cells tested (n = 58 of 126 VSMCs, pH 6.5-5.0). The percentage of responsive cells and the current amplitude increased as the external H(+) concentration increased (pH(6.0), n = 28/65 VSMCs responsive, mean current density = 8.1 +/- 1.2 pA/pF). Extracellular acidosis (pH(6.0)) shifted the whole cell reversal potential toward the Nernst potential of Na(+) (n = 6) and substitution of extracellular Na(+) by N-methyl-d-glucamine abolished the inward current (n = 6), indicating that Na(+) is a major charge carrier. The broad-spectrum ASIC blocker amiloride (20 microM) inhibited proton-induced currents to 16.5 +/- 8.7% of control (n = 6, pH(6.0)). Psalmotoxin 1 (PcTx1), an ASIC1a inhibitor and ASIC1b activator, had mixed effects: PcTx1 either 1) abolished H(+)-induced currents (11% of VSMCs, 5/45), 2) enhanced or promoted activation of H(+)-induced currents (76%, 34/45), or 3) failed to promote H(+) activation in nonresponsive VSMCs (13%, 6/45). These findings suggest that freshly dissociated cerebral artery VSMCs express ASIC-like channels, which are predominantly formed by ASIC1b.

  4. Cathepsin K in Lymphangioleiomyomatosis: LAM Cell-Fibroblast Interactions Enhance Protease Activity by Extracellular Acidification.

    Science.gov (United States)

    Dongre, Arundhati; Clements, Debbie; Fisher, Andrew J; Johnson, Simon R

    2017-08-01

    Lymphangioleiomyomatosis (LAM) is a rare disease in which LAM cells and fibroblasts form lung nodules and it is hypothesized that LAM nodule-derived proteases cause cyst formation and tissue damage. On protease gene expression profiling in whole lung tissue, cathepsin K gene expression was 40-fold overexpressed in LAM compared with control lung tissue (P ≤ 0.0001). Immunohistochemistry confirmed cathepsin K protein was expressed in LAM but not control lungs. Cathepsin K gene expression and protein and protease activity were detected in LAM-associated fibroblasts but not the LAM cell line 621-101. In lung nodules, cathepsin K immunoreactivity predominantly co-localized with LAM-associated fibroblasts. In vitro, fibroblast extracellular cathepsin K activity was minimal at pH 7.5 but significantly enhanced at pH 7 and 6. 621-101 cells reduced extracellular pH with acidification dependent on 621-101 mechanistic target of rapamycin activity and net hydrogen ion exporters, particularly sodium bicarbonate co-transporters and carbonic anhydrases, which were also expressed in LAM lung tissue. In LAM cell-fibroblast co-cultures, acidification paralleled cathepsin K activity, and both were reduced by sodium bicarbonate co-transporter (P ≤ 0.0001) and carbonic anhydrase inhibitors (P = 0.0021). Our findings suggest that cathepsin K activity is dependent on LAM cell-fibroblast interactions, and inhibitors of extracellular acidification may be potential therapies for LAM. Copyright © 2017 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  5. Alterations in the extracellular matrix organization associated with the reexpression of tumorigenicity in human cell hybrids.

    Science.gov (United States)

    Der, C J; Stanbridge, E J

    1980-10-15

    The expression of fibronectin on the cell surface was evaluated on a series of intraspecific human cell hybrids formed between HeLa and normal fibroblast strains. Although these hybrids continued to express many of the in vitro transformation properties of their corresponding tumorigenic HeLa parent, they were now unable to form tumors when inoculated into athymic nude mice. From these suppressed hybrid populations, rare tumorigenic segregant subpopulations arose which had regained their tumorigenic capacity. A comparison of the expression of fibronectin on the cell surface was made between these tumorigenic segregant cell lines and their corresponding non-tumorigenic HeLa/fibroblast hybrid. Following specific immunofluorescent staining for fibronectin, a striking alteration in the cell surface organization was observed to correspond with the reexpression of tumorigenicity in these hybrids. Tumorigenic HeLa/fibroblast hybrids were also significantly altered in both their cellular and colonial morphology. Double immunofluorescent staining to simultaneously visualize both surface fibronectin and collagen revealed that these two extracellular matrix proteins displayed an extensive degree of codistribution and expressed a coordinate shift in organization which correlated with the appearance of tumorigenic segregant hybrid populations. These observations are in agreement with the apparently close structural association between fibronectin and collagen and suggest that the organization of these two components in the extracellular matrix may be an important determinant for in vivo growth potential.

  6. The role of extracellular matrix metalloproteinase inducer (EMMPRIN) in the regulation of bovine endometrial cell functions.

    Science.gov (United States)

    Mishra, Birendra; Kizaki, Keiichiro; Sato, Takashi; Ito, Akira; Hashizume, Kazuyoshi

    2012-06-01

    Extracellular matrix metalloproteinase inducer (EMMPRIN) is a cell surface glycoprotein that stimulates the production of several matrix metalloproteinases (MMPs) for tissue remodeling. Previously, we detected EMMPRIN in the bovine endometrium, and it is mainly expressed in the luminal and glandular epithelium whereas MMPs are expressed in the underlying stroma. From this expression pattern, we hypothesized that EMMPRIN may regulate stromal MMPs in endometrial cell functions. To test this hypothesis, a coculture of epithelial and stromal cells was performed using a transwell system. In the coculture, epithelial cells were cultured on the insert membrane and stromal cell on the surface of well plates. Expression of stromal MMP-2 and MMP-14 was significantly higher in coculture with epithelial cell. Further, with the addition of anti-EMMPRIN antibody into the epithelial cell compartment, the expression of stromal EMMPRIN and MMP-2 and MMP-14 was decreased. To identify the active site of EMMPRIN for the augmentation of MMPs, EMMPRIN synthetic peptides that correspond to the extracellular loop domain-I (EM1, EM2, EM3, and EM4) were added into the epithelial cell compartment, and only EM2 at a higher dose interfered with EMMPRIN-mediated expression of MMP-14. Next, we examined the effects of progesterone and/or estrogen on the expression of EMMPRIN, MMP-2, and MMP-14. Progesterone (300 nM) significantly stimulated the expression of EMMPRIN but had no effects on any of the MMPs. These results suggest that EMMPRIN derived from epithelial cells regulates MMPs in the endometrium under progesterone-rich conditions and may thereby modulate bovine endometrial cell functions during gestation.

  7. Vinculin is required for cell polarization, migration, and extracellular matrix remodeling in 3D collagen.

    Science.gov (United States)

    Thievessen, Ingo; Fakhri, Nikta; Steinwachs, Julian; Kraus, Viola; McIsaac, R Scott; Gao, Liang; Chen, Bi-Chang; Baird, Michelle A; Davidson, Michael W; Betzig, Eric; Oldenbourg, Rudolf; Waterman, Clare M; Fabry, Ben

    2015-11-01

    Vinculin is filamentous (F)-actin-binding protein enriched in integrin-based adhesions to the extracellular matrix (ECM). Whereas studies in 2-dimensional (2D) tissue culture models have suggested that vinculin negatively regulates cell migration by promoting cytoskeleton-ECM coupling to strengthen and stabilize adhesions, its role in regulating cell migration in more physiologic, 3-dimensional (3D) environments is unclear. To address the role of vinculin in 3D cell migration, we analyzed the morphodynamics, migration, and ECM remodeling of primary murine embryonic fibroblasts (MEFs) with cre/loxP-mediated vinculin gene disruption in 3D collagen I cultures. We found that vinculin promoted 3D cell migration by increasing directional persistence. Vinculin was necessary for persistent cell protrusion, cell elongation, and stable cell orientation in 3D collagen, but was dispensable for lamellipodia formation, suggesting that vinculin-mediated cell adhesion to the ECM is needed to convert actin-based cell protrusion into persistent cell shape change and migration. Consistent with this finding, vinculin was necessary for efficient traction force generation in 3D collagen without affecting myosin II activity and promoted 3D collagen fiber alignment and macroscopical gel contraction. Our results suggest that vinculin promotes directionally persistent cell migration and tension-dependent ECM remodeling in complex 3D environments by increasing cell-ECM adhesion and traction force generation. © FASEB.

  8. Extracellular ATP4- promotes cation fluxes in the J774 mouse macrophage cell line

    International Nuclear Information System (INIS)

    Steinberg, T.H.; Silverstein, S.C.

    1987-01-01

    Extracellular ATP stimulates transmembrane ion fluxes in the mouse macrophage cell line J774. In the presence of Mg2+, nonhydrolyzable ATP analogs and other purine and pyrimidine nucleotides do not elicit this response, suggesting the presence of a specific receptor for ATP on the macrophage plasma membrane. One candidate for such a receptor is the ecto-ATPase expressed on these cells. We, therefore, investigated the role of this enzyme in ATP-induced 86 Rb+ efflux in J774 cells. The ecto-ATPase had a broad nucleotide specificity and did not hydrolyze extracellular ATP in the absence of divalent cations. 86 Rb+ efflux was not blocked by inhibition of the ecto-ATPase and did not require Ca2+ or Mg2+. In fact, ATP-stimulated 86 Rb+ efflux was inhibited by Mg2+ and correlated with the availability of ATP4- in the medium. In the absence of divalent cations, the slowly hydrolyzable ATP analogs adenosine 5'-(beta, gamma-imido)triphosphate (AMP-PNP) and adenosine 5'-O-(3-thio)triphosphate (ATP-gamma-S) also stimulated 86 Rb+ efflux, albeit at higher concentrations than that required for ATP4-. Exposure of J774 cells to 10 mM ATP for 45 min caused death of 95% of cells. By this means we selected variant J774 cells that did not exhibit 86 Rb+ efflux in the presence of extracellular ATP but retained ecto-ATPase activity. These results show that the ecto-ATPase of J774 cells does not mediate the effects of ATP on these cells; that ATP4- and not MgATP2- promotes 86 Rb+ efflux from these cells; and that hydrolysis of ATP is not required to effect this change in membrane permeability. These findings suggest that J774 cells possess a plasma membrane receptor which binds ATP4-, AMP-PNP, and ATP-gamma-S, and that the ecto-ATPase limits the effects of ATP on these cells by hydrolyzing Mg-ATP2-

  9. Differential sensitivity of epithelial cells to extracellular matrix in polarity establishment.

    Directory of Open Access Journals (Sweden)

    Shigenobu Yonemura

    Full Text Available Establishment of apical-basal polarity is crucial for epithelial sheets that form a compartment in the body, which function to maintain the environment in the compartment. Effects of impaired polarization are easily observed in three-dimensional (3-D culture systems rather than in two-dimensional (2-D culture systems. Although the mechanisms for establishing the polarity are not completely understood, signals from the extracellular matrix (ECM are considered to be essential for determining the basal side and eventually generating polarity in the epithelial cells. To elucidate the common features and differences in polarity establishment among various epithelial cells, we analyzed the formation of epithelial apical-basal polarity using three cell lines of different origin: MDCK II cells (dog renal tubules, EpH4 cells (mouse mammary gland, and R2/7 cells (human colon expressing wild-type α-catenin (R2/7 α-Cate cells. These cells showed clear apical-basal polarity in 2-D cultures. In 3-D cultures, however, each cell line displayed different responses to the same ECM. In MDCK II cells, spheroids with a single lumen formed in both Matrigel and collagen gel. In R2/7 α-Cate cells, spheroids showed similar apical-basal polarity as that seen in MDCK II cells, but had multiple lumens. In EpH4 cells, the spheroids displayed an apical-basal polarity that was opposite to that seen in the other two cell types in both ECM gels, at least during the culture period. On the other hand, the three cell lines showed the same apical-basal polarity both in 2-D cultures and in 3-D cultures using the hanging drop method. The three lines also had similar cellular responses to ECM secreted by the cells themselves. Therefore, appropriate culture conditions should be carefully determined in advance when using various epithelial cells to analyze cell polarity or 3-D morphogenesis.

  10. Apoptotic Tumor Cell-Derived Extracellular Vesicles as Important Regulators of the Onco-Regenerative Niche

    Directory of Open Access Journals (Sweden)

    Christopher D. Gregory

    2018-05-01

    Full Text Available Cells undergoing apoptosis produce heterogeneous populations of membrane delimited extracellular vesicles (Apo-EVs which vary not only in size—from tens of nanometers to several microns—but also in molecular composition and cargo. Apo-EVs carry a variety of potentially biologically active components, including small molecules, proteins, and nucleic acids. Larger forms of Apo-EVs, commonly termed “apoptotic bodies,” can carry organelles, such as mitochondria and nuclear fragments. Molecules displayed on the surface of extracellular vesicles (EVs can contribute substantially to their size, as well as their functions. Thus far, relatively little is known of the functional significance of Apo-EVs apart from their roles in fragmentation of dying cells and indicated immunomodulatory activities. Here, we discuss EV production by dying tumor cells and consider the possible roles of Apo-EVs in a cell death-driven sector of the tumor microenvironment known as the onco-regenerative niche (ORN. We propose that tumor-derived Apo-EVs are significant vehicles of the ORN, functioning as critical intercellular communicators that activate oncogenic tissue repair and regeneration pathways. We highlight important outstanding questions and suggest that Apo-EVs may harbor novel therapeutic targets.

  11. Vectorization of biomacromolecules into cells using extracellular vesicles with enhanced internalization induced by macropinocytosis.

    Science.gov (United States)

    Nakase, Ikuhiko; Noguchi, Kosuke; Fujii, Ikuo; Futaki, Shiroh

    2016-10-17

    Extracellular vesicles (EVs, exosomes) are approximately 30- to 200-nm-long vesicles that have received increased attention due to their role in cell-to-cell communication. Although EVs are highly anticipated to be a next-generation intracellular delivery tool because of their pharmaceutical advantages, including non-immunogenicity, their cellular uptake efficacy is low because of the repulsion of EVs and negatively charged cell membranes and size limitations in endocytosis. Here, we demonstrate a methodology for achieving enhanced cellular EV uptake using arginine-rich cell-penetrating peptides (CPPs) to induce active macropinocytosis. The induction of macropinocytosis via a simple modification to the exosomal membrane using stearylated octaarginine, which is a representative CPP, significantly enhanced the cellular EV uptake efficacy. Consequently, effective EV-based intracellular delivery of an artificially encapsulated ribosome-inactivating protein, saporin, in EVs was attained.

  12. NG2 proteoglycan increases mesangial cell proliferation and extracellular matrix production

    International Nuclear Information System (INIS)

    Xiong Jing; Wang Yang; Zhu, Zhonghua; Liu Jianshe; Wang Yumei; Zhang Chun; Hammes, Hans-Peter; Lang, Florian; Feng Yuxi

    2007-01-01

    As a membrane-spanning protein, NG2 chondroitin sulfate proteoglycan interacts with molecules on both sides of plasma membrane. The present study explored the role of NG2 in the pathogenesis of diabetic nephropathy. In the normal kidneys, NG2 was observed predominantly in glomerular mesangium, Bowman's capsule and interstitial vessels. Both mRNA and protein expression in kidneys was significantly higher in strepozotocin-induced diabetic rats than that in normal rats. In the cultured rat mesangial cell line HBZY-1, overexpression of NG2 promoted mesangial cell proliferation and extracellular matrix (ECM) production, such as type VI collagen and laminin. Furthermore, target knockdown of NG2 resulted in decreased cell proliferation and ECM formation. The observations suggest that NG2 is up-regulated in diabetic nephropathy. It actively participates in the development and progression of glomerulosclerosis by stimulating proliferation of mesangial cells and deposition of ECM

  13. Electric field stimulation through a substrate influences Schwann cell and extracellular matrix structure

    Science.gov (United States)

    Nguyen, Hieu T.; Wei, Claudia; Chow, Jacqueline K.; Nguy, Lindsey; Nguyen, Hieu K.; Schmidt, Christine E.

    2013-08-01

    Objective. Electric field (EF) stimulation has been used to cue cell growth for tissue engineering applications. In this study, we explore the electrical parameters and extracellular mechanisms that elicit changes in cell behavior when stimulated through the substrate. Approach. Rat Schwann cell morphology was compared when exposed to EF through the media or a conductive indium tin oxide substrate. Ionic and structural effects were then analyzed on Matrigel and collagen I, respectively. Main results. When stimulating through media, cells had greater alignment perpendicular to the EF with higher current densities (106 mA cm-2 at 245 mV mm-1), and reached maximum alignment within 8 h. Stimulation through the substrate with EF (up to 110 mV mm-1) did not affect Schwann cell orientation, however the EF caused extracellular matrix (ECM) coatings on substrates to peel away, suggesting EF can physically change the ECM. Applying alternating current (ac) 2-1000 Hz signals through the media or substrate both caused cells to flatten and protrude many processes, without preferential alignment. Matrigel exposed to a substrate EF of 10 mV mm-1 for 2 h had a greater calcium concentration near the cathode, but quickly dissipated when the EF was removed. Schwann cells seeded 7 d after gels were exposed to substrate EF still aligned perpendicular to the EF direction. Microscopy of collagen I exposed to substrate EF shows alignment and bundling of fibrils. Significance. These findings demonstrate EF exposure can control Schwann cell alignment and morphology, change ECM bulk/surface architecture, and align ECM structures.

  14. Hyaluronan protection of corneal endothelial cells against extracellular histones after phacoemulsification.

    Science.gov (United States)

    Kawano, Hiroki; Sakamoto, Taiji; Ito, Takashi; Miyata, Kazunori; Hashiguchi, Teruto; Maruyama, Ikuro

    2014-11-01

    To determine the effect of histones on corneal endothelial cells generated during cataract surgery. Kagoshima University Hospital, Kagoshima, Japan. Experimental study. Standard phacoemulsification was performed on enucleated pig eyes. Histones in the anterior segment of the eye were determined by immunohistochemistry. Cultured human corneal endothelial cells were exposed to histones for 18 hours, and cell viability was determined by 2-(2-methoxy-4-nitrophenyl)-3-(4-nitro-phenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium, monosodium salt assay. The concentration of interleukin-6 (IL-6) in the culture medium of human corneal endothelial cells was measured using enzyme-linked immunosorbent assay. The effects of signal inhibitors U0126, SB203580, and SP600125 were evaluated. The protective effect of hyaluronan against histones was evaluated in human corneal endothelial cells with and without hyaluronan. Cellular debris containing histones was observed in the anterior chamber of pig eyes after phacoemulsification. Exposure of human corneal endothelial cells to 50 μg/mL of histones or more led to cytotoxic effects. The IL-6 concentration was significantly increased dose dependently after exposure of human corneal endothelial cells to histones (Phistone-induced IL-6 production was significantly decreased by extracellular signal-regulated kinases 1/2 and p-38 mitogen-activated protein kinase inhibitors (Phistones caused formation of histone aggregates, decreased the cytotoxic effects of the histones, and blocked the increase in IL-6 (PHistones were released extracellularly during phacoemulsification and exposure of human corneal endothelial cells to histones increased the IL-6 secretion. The intraoperative use of hyaluronan may decrease the cytotoxic effects of histones released during cataract surgery. No author has a financial or proprietary interest in any material or method mentioned. Copyright © 2014 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  15. Extracellular histones reduce survival and angiogenic responses of late outgrowth progenitor and mature endothelial cells.

    Science.gov (United States)

    Mena, H A; Carestia, A; Scotti, L; Parborell, F; Schattner, M; Negrotto, S

    2016-02-01

    ESSENTIALS: Extracellular histones are highly augmented in sites of neovessel formation, such as regeneration tissues. We studied histone effect on survival and angiogenic activity of mature and progenitor endothelial cells. Extracellular histones trigger apoptosis and pyroptosis and reduce angiogenesis in vivo and in vitro. Histone blockade can be useful as a therapeutic strategy to improve angiogenesis and tissue regeneration. Extracellular histones are highly augmented in sites of neovessel formation, like regeneration tissues. Their cytotoxic effect has been studied in endothelial cells, although the mechanism involved and their action on endothelial colony-forming cells (ECFCs) remain unknown. To study the effect of histones on ECFC survival and angiogenic functions and compare it with mature endothelial cells. Nuclear morphology analysis showed that each human recombinant histone triggered both apoptotic-like and necrotic-like cell deaths in both mature and progenitor endothelial cells. While H1 and H2A exerted a weak toxicity, H2B, H3 and H4 were the most powerful. The percentage of apoptosis correlated with the percentage of ECFCs exhibiting caspase-3 activation and was zeroed by the pan-caspase inhibitor Z-VAD-FMK. Necrotic-like cell death was also suppressed by this compound and the caspase-1 inhibitor Ac-YVAD-CMK, indicating that histones triggered ECFC pyroptosis. All histones, at non-cytotoxic concentrations, reduced migration and H2B, H3 and H4 induced cell cycle arrest and impaired tubulogenesis via p38 activation. Neutrophil-derived histones exerted similar effects. In vivo blood vessel formation in the quail chorioallantoic membrane was also reduced by H2B, H3 and H4. Their cytotoxic and antiangiogenic effects were suppressed by unfractioned and low-molecular-weight heparins and the combination of TLR2 and TLR4 blocking antibodies. Histones trigger both apoptosis and pyroptosis of ECFCs and inhibit their angiogenic functions. Their cytotoxic and

  16. Lymphocyte interactions with the extracellular matrix of malignant cells in vítro: A morphological and immunocytochemical study

    OpenAIRE

    Logothetou-Rella, H.

    1993-01-01

    The interactions of lymphocytes with the glycosaminoglycans-protease-membrane extracellular matrix, produced by mixed cell cultures of normal with malignant cell clones, were examined. Pre-activated and activated heterologous peripheral lymphocytes were used. Co-cultures of activated lymphocytes with al1 cell types used, formed identical cell nodules. Histology of cell nodules showed that activated lymphocytes were cytolytic to pure normal or malignant cell clo...

  17. Inhibitory effect of extracellular purine nucleotide and nucleoside concentrations on T cell proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Weiler, Monica [Department of Medicine III and Transfusion Medicine, University Hospital Grosshadern, Ludwig-Maximilians-University, Munich (Germany); Schmetzer, Helga [Helmholtz Center Munich (Germany); German Research Center for Environmental Health, Munich (Germany); Braeu, Marion; Buhmann, Raymund [Helmholtz Center Munich (Germany); German Research Center for Environmental Health, Munich (Germany); Department of Medicine III and Transfusion Medicine, University Hospital Grosshadern, Ludwig-Maximilians-University, Munich (Germany)

    2016-11-15

    The release of nucleic acids and derivatives after tissue-injury may affect cellular immune-response. We studied the impact of extracellular ribo-, desoxyribonucleotides and nucleosides on T-cell immunity. Peripheral-blood-mononuclear-cells (PBMCs) or isolated CD3{sup +}T-cells obtained from 6 healthy donors were stimulated via CD3/CD28 Dynabeads or dendritic cells (DCs) in the presence or absence of pyrimidine-, purine-nucleotides and -nucleosides (range 2–200 µM). Addition of deoxy-, guanosine-triphosphate (dGTP, GTP) and guanosine resulted concentration dependent in a complete, adenosine-triphosphate (ATP) in a partial inhibition of the induced T-cell-proliferation. Deoxyadenosine-triphosphate (dATP), adenosine and the pyrimidine-ribo- and -deoxyribonucleotides displayed no inhibitory capacity. Inhibitory effects of dGTP and GTP, but not of guanosine and ATP were culture-media-dependent and could be almost abrogated by use of the serum-free lymphocyte-culture-media X-Vivo15 instead of RPMI1640 with standard-supplementation. In contrast to RPMI1640, X-Vivo15 resulted in a significant down-regulation of the cell-surface-located ectonucleotidases CD39 (Ecto-Apyrase) and CD73 (Ecto-5′-Nucleotidase), critical for the extracellular nucleotides-hydrolysis to nucleosides, explaining the loss of inhibition mediated by dGTP and GTP, but not Guanosine. In line with previous findings ATP was found to exert immunosuppressive effects on T-cell-proliferation. Purine-nucleotides, dGTP and GTP displayed a higher inhibitory capacity, but seem to be strictly dependent on the microenvironmental conditions modulating the responsiveness of the respective T-lymphocytes. Further evaluation of experimental and respective clinical settings should anticipate these findings.

  18. Inhibitory effect of extracellular purine nucleotide and nucleoside concentrations on T cell proliferation

    International Nuclear Information System (INIS)

    Weiler, Monica; Schmetzer, Helga; Braeu, Marion; Buhmann, Raymund

    2016-01-01

    The release of nucleic acids and derivatives after tissue-injury may affect cellular immune-response. We studied the impact of extracellular ribo-, desoxyribonucleotides and nucleosides on T-cell immunity. Peripheral-blood-mononuclear-cells (PBMCs) or isolated CD3 + T-cells obtained from 6 healthy donors were stimulated via CD3/CD28 Dynabeads or dendritic cells (DCs) in the presence or absence of pyrimidine-, purine-nucleotides and -nucleosides (range 2–200 µM). Addition of deoxy-, guanosine-triphosphate (dGTP, GTP) and guanosine resulted concentration dependent in a complete, adenosine-triphosphate (ATP) in a partial inhibition of the induced T-cell-proliferation. Deoxyadenosine-triphosphate (dATP), adenosine and the pyrimidine-ribo- and -deoxyribonucleotides displayed no inhibitory capacity. Inhibitory effects of dGTP and GTP, but not of guanosine and ATP were culture-media-dependent and could be almost abrogated by use of the serum-free lymphocyte-culture-media X-Vivo15 instead of RPMI1640 with standard-supplementation. In contrast to RPMI1640, X-Vivo15 resulted in a significant down-regulation of the cell-surface-located ectonucleotidases CD39 (Ecto-Apyrase) and CD73 (Ecto-5′-Nucleotidase), critical for the extracellular nucleotides-hydrolysis to nucleosides, explaining the loss of inhibition mediated by dGTP and GTP, but not Guanosine. In line with previous findings ATP was found to exert immunosuppressive effects on T-cell-proliferation. Purine-nucleotides, dGTP and GTP displayed a higher inhibitory capacity, but seem to be strictly dependent on the microenvironmental conditions modulating the responsiveness of the respective T-lymphocytes. Further evaluation of experimental and respective clinical settings should anticipate these findings.

  19. Ribonucleic artefacts: are some extracellular RNA discoveries driven by cell culture medium components?

    Science.gov (United States)

    Tosar, Juan Pablo; Cayota, Alfonso; Eitan, Erez; Halushka, Marc K; Witwer, Kenneth W

    2017-01-01

    In a recently published study, Anna Krichevsky and colleagues raise the important question of whether results of in vitro extracellular RNA (exRNA) studies, including extracellular vesicle (EV) investigations, are confounded by the presence of RNA in cell culture medium components such as foetal bovine serum (FBS). The answer, according to their data, is a resounding "yes". Even after lengthy ultracentrifugation to remove bovine EVs from FBS, the majority of exRNA in FBS remained. Although technical factors may affect the degree of depletion, residual EVs and exRNA in FBS could influence the conclusions of in vitro studies: certainly, for secreted RNA, and possibly also for cell-associated RNA. In this commentary, we critically examine some of the literature in this field, including a recent study from some of the authors of this piece, in light of the Wei et al. study and explore how cell culture-derived RNAs may affect what we think we know about EV RNAs. These findings hold particular consequence as the field moves towards a deeper understanding of EV-RNA associations and potential functions.

  20. Mesenchymal stem cell-derived extracellular vesicles: a glimmer of hope in treating Alzheimer's disease.

    Science.gov (United States)

    Liew, Lee Chuen; Katsuda, Takeshi; Gailhouste, Luc; Nakagama, Hitoshi; Ochiya, Takahiro

    2017-01-01

    One of the pathological hallmarks of Alzheimer's disease (AD) is the presence of extracellular plaques resulting from the accumulation of beta-amyloid peptide (Aβ). To date, a definitive cure for this disease is still lacking as the currently approved drugs used are mainly symptomatic treatments. The revolutionary discovery of extracellular vesicles (EVs) has shed new light on the development of disease-modifying treatments for AD, owing to their potential in delivering the therapeutic agents to the brain. The feasibility of harnessing EVs for clinical applications is highly dependent on the donor cell, which determines the intrinsic properties of EVs. The merit of mesenchymal stem cells (MSCs) as therapeutic delivery vehicles, and the proven therapeutic effects of the EVs derived from these cells, make researchers esteem MSCs as ideal producers of EVs. Therefore, MSC-derived EVs (MSC-EVs) emerge to be an appealing therapeutic delivery approach for the treatment of AD. Here, we discuss perspectives on the therapeutic strategies using MSC-EVs to treat AD and the associated challenges in clinical application. © The Japanese Society for Immunology. 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  1. In vitro evaluation of the interactions between human corneal endothelial cells and extracellular matrix proteins

    International Nuclear Information System (INIS)

    Choi, Jin San; Kim, Eun Young; Kim, Min Jeong; Giegengack, Matthew; Khan, Faraaz A; Soker, Shay; Khang, Gilson

    2013-01-01

    The corneal endothelium is the innermost cell layer of the cornea and rests on Descemet's membrane consisting of various extracellular matrix (ECM) proteins which can directly affect the cellular behaviors such as cell adhesion, proliferation, polarity, morphogenesis and function. The objective of this study was to investigate the interactions between the ECM environment and human corneal endothelial cells (HCECs), with the ultimate goal to improve cell proliferation and function in vitro. To evaluate the interaction of HCECs with ECM proteins, cells were seeded on ECM-coated tissue culture dishes, including collagen type I (COL I), collagen type IV (COL IV), fibronectin (FN), FNC coating mix (FNC) and laminin (LM). Cell adhesion and proliferation of HCECs on each substratum and expression of CEC markers were studied. The results showed that HCECs plated on the COL I, COL IV, FN and FNC-coated plates had enhanced cell adhesion initially; the number for COL I, COL IV, FN and FNC was significantly higher than the control (P < 0.05). In addition, cells grown on ECM protein-coated dishes showed more compact cellular morphology and CEC marker expression compared to cells seeded on uncoated dishes. Collectively, our results suggest that an adequate ECM protein combination can provide a long-term culture environment for HCECs for corneal endothelium transplantation. (paper)

  2. In vitro extracellular matrix model to evaluate stroma cell response to transvaginal mesh.

    Science.gov (United States)

    Wu, Ming-Ping; Huang, Kuan-Hui; Long, Cheng-Yu; Yang, Chau-Chen; Tong, Yat-Ching

    2014-04-01

    The use of surgical mesh for female pelvic floor reconstruction has increased in recent years. However, there is paucity of information about the biological responses of host stroma cells to different meshes. This study was aimed to establish an in vitro experimental model to study the micro-environment of extracellular matrix (ECM) with embedded mesh and the stroma cell behaviors to different synthetic meshes. Matrigel multi-cellular co-culture system with embedded mesh was used to evaluate the interaction of stroma cells and synthetic mesh in a simulated ECM environment. Human umbilical vein endothelial cells (HUVEC) and NIH3T3 fibroblasts were inoculated in the system. The established multi-cellular Matrigel co-culture system was used to detect stroma cell recruitment and tube formation ability for different synthetic meshes. HUVEC and NIH3T3 cells were recruited into the mesh interstices and organized into tube-like structures in type I mesh material from Perigee, Marlex and Prolift 24 hr after cell inoculation. On the contrary, there was little recruitment of HUVEC and NIH3T3 cells into the type III mesh of intra-vaginal sling (IVS). The Matrigel multi-cellular co-culture system with embedded mesh offers a useful in vitro model to study the biological behaviors of stroma cells in response to different types of synthetic meshes. The system can help to select ideal mesh candidates before actual implantation into the human body. © 2013 Wiley Periodicals, Inc.

  3. Platelet-tumor cell interaction with the subendothelial extracellular matrix: relationship to cancer metastasis

    Energy Technology Data Exchange (ETDEWEB)

    Yahalom, J; Biran, S; Fuks, Z; Vlodavsky, I [Hadassah University Hospital, Jerusalem (Israel). Dept. of Radiation and Clinical Oncology; Eldor, A [Hadassah University Hospital, Jerusalem (Israel). Dept. of Hematology

    1985-04-01

    Dissemination of neoplastic cells within the body involves invasion of blood vessels by tumor cells. This requires adhesion of blood-borne cells to the luminal surface of the vascular endothelium, invasion through the endothelial cell layer and local dissolution of the subendothelial basement membrane. The authors studied the interaction of platelets and tumor cells with cultured vascular endothelial cells and their secreted basement membrane-like extracellular matrix (ECM). Interaction of platelets with this ECM was associated with platelet activation, aggregation and degradation of heparan sulfate in the ECM by means of the platelet heparitinase. Biochemical and scanning electron microscopy (SEM) studies have demonstrated that platelets may detect even minor gaps between adjacent endothelial cells and degrade the ECM heparan sulfate. Platelets were also shown to recruit lymphoma cells into minor gaps in the vascular endothelium. It is suggested that the platelet heparitinase is involved in the impairment of the integrity of the vessel wall and thus play a role in tumor cell metastasis.

  4. Do endothelial cells belong to the primitive stem leukemic clone in CML? Role of extracellular vesicles.

    Science.gov (United States)

    Ramos, Teresa L; Sánchez-Abarca, Luis Ignacio; López-Ruano, Guillermo; Muntión, Sandra; Preciado, Silvia; Hernández-Ruano, Montserrat; Rosado, Belén; de las Heras, Natalia; Chillón, M Carmen; Hernández-Hernández, Ángel; González, Marcos; Sánchez-Guijo, Fermín; Del Cañizo, Consuelo

    2015-08-01

    The expression of BCR-ABL in hematopoietic stem cells is a well-defined primary event in chronic myeloid leukemia (CML). Some reports have described the presence of BCR-ABL on endothelial cells from CML patients, suggesting the origin of the disease in a primitive hemangioblastic cell. On the other hand, extracellular vesicles (EVs) released by CML leukemic cells are involved in the angiogenesis modulation process. In the current work we hypothesized that EVs released from BCR-ABL(+) cells may carry inside the oncogene that can be transferred to endothelial cells leading to the expression of both BCR-ABL transcript and the oncoprotein. EVs from K562 cells and plasma of newly diagnosed CML patients were isolated by ultracentrifugation. RT-PCR analysis detected the presence of BCR-ABL RNA in the EVs isolated from both K562 cells and plasma of CML patients. The incorporation of these EVs into endothelial cells was demonstrated by flow cytometry and fluorescence microscopy showed that after 24h of incubation most EVs were incorporated. BCR-ABL transcripts were detected in all experiments on endothelial cells incubated with EVs from both sources. The presence of BCR-ABL on endothelial cells incubated with Philadelphia(+) EVs was also confirmed by Western blot assays. In summary, endothelial cells acquire BCR-ABL RNA and the oncoprotein after incubation with EVs released from Ph(+) positive cells (either from K562 cells or from plasma of newly diagnosed CML patients). This results challenge the hypothesis that endothelial cells may be part of the Philadelphia(+) clone in CML. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Hypoxia-driven angiogenesis: role of tip cells and extracellular matrix scaffolding.

    Science.gov (United States)

    Germain, Stéphane; Monnot, Catherine; Muller, Laurent; Eichmann, Anne

    2010-05-01

    Angiogenesis is a highly coordinated tissue remodeling process leading to blood vessel formation. Hypoxia triggers angiogenesis via induction of expression of growth factors such as vascular endothelial growth factor (VEGF). VEGF instructs endothelial cells to form tip cells, which lead outgrowing capillary sprouts, whereas Notch signaling inhibits sprout formation. Basement membrane deposition and mechanical cues from the extracellular matrix (ECM) induced by hypoxia may participate to coordinated vessel sprouting in conjunction with the VEGF and Notch signaling pathways. Hypoxia regulates ECM composition, deposition, posttranslational modifications and rearrangement. In particular, hypoxia-driven vascular remodeling is dynamically regulated through modulation of ECM-modifying enzyme activities that eventually affect both matricellular proteins and growth factor availability. Better understanding of the complex interplay between endothelial cells and soluble growth factors and mechanical factors from the ECM will certainly have significant implications for understanding the regulation of developmental and pathological angiogenesis driven by hypoxia.

  6. Extracellular ATP drives breast cancer cell migration and metastasis via S100A4 production by cancer cells and fibroblasts.

    Science.gov (United States)

    Liu, Ying; Geng, Yue-Hang; Yang, Hui; Yang, Han; Zhou, Yan-Ting; Zhang, Hong-Quan; Tian, Xin-Xia; Fang, Wei-Gang

    2018-05-04

    Our previous work has demonstrated that extracellular ATP is an important pro-invasive factor, and in this study, we tapped into a possible mechanism involved. We discovered that ATP could upregulate both the intracellular expression and secretion of S100A4 in breast cancer cells and fibroblasts. Apart from stimulating breast cancer cell motility via intracellular S100A4, ATP enhanced the ability of breast cancer cells to transform fibroblasts into cancer-associated fibroblast (CAF)-like cells, which in turn secreted S100A4 to further promote cancer cell motility. Both apyrase and niclosamide treatments could inhibit metastasis of inoculated tumors to lung, liver and kidney in mice model, and CAFs from these treated tumors exhibited weakened migration-stimulating capacity for breast cancer cells. Collectively, our data indicate that extracellular ATP promotes the interactions between breast cancer cells and fibroblasts, which work collaboratively via production of S100A4 to exacerbate breast cancer metastasis. Copyright © 2018. Published by Elsevier B.V.

  7. Extracellular Protease Inhibition Alters the Phenotype of Chondrogenically Differentiating Human Mesenchymal Stem Cells (MSCs) in 3D Collagen Microspheres.

    Science.gov (United States)

    Han, Sejin; Li, Yuk Yin; Chan, Barbara Pui

    2016-01-01

    Matrix remodeling of cells is highly regulated by proteases and their inhibitors. Nevertheless, how would the chondrogenesis of mesenchymal stem cells (MSCs) be affected, when the balance of the matrix remodeling is disturbed by inhibiting matrix proteases, is incompletely known. Using a previously developed collagen microencapsulation platform, we investigated whether exposing chondrogenically differentiating MSCs to intracellular and extracellular protease inhibitors will affect the extracellular matrix remodeling and hence the outcomes of chondrogenesis. Results showed that inhibition of matrix proteases particularly the extracellular ones favors the phenotype of fibrocartilage rather than hyaline cartilage in chondrogenically differentiating hMSCs by upregulating type I collagen protein deposition and type II collagen gene expression without significantly altering the hypertrophic markers at gene level. This study suggests the potential of manipulating extracellular proteases to alter the outcomes of hMSC chondrogenesis, contributing to future development of differentiation protocols for fibrocartilage tissues for intervertebral disc and meniscus tissue engineering.

  8. Extracellular Protease Inhibition Alters the Phenotype of Chondrogenically Differentiating Human Mesenchymal Stem Cells (MSCs in 3D Collagen Microspheres.

    Directory of Open Access Journals (Sweden)

    Sejin Han

    Full Text Available Matrix remodeling of cells is highly regulated by proteases and their inhibitors. Nevertheless, how would the chondrogenesis of mesenchymal stem cells (MSCs be affected, when the balance of the matrix remodeling is disturbed by inhibiting matrix proteases, is incompletely known. Using a previously developed collagen microencapsulation platform, we investigated whether exposing chondrogenically differentiating MSCs to intracellular and extracellular protease inhibitors will affect the extracellular matrix remodeling and hence the outcomes of chondrogenesis. Results showed that inhibition of matrix proteases particularly the extracellular ones favors the phenotype of fibrocartilage rather than hyaline cartilage in chondrogenically differentiating hMSCs by upregulating type I collagen protein deposition and type II collagen gene expression without significantly altering the hypertrophic markers at gene level. This study suggests the potential of manipulating extracellular proteases to alter the outcomes of hMSC chondrogenesis, contributing to future development of differentiation protocols for fibrocartilage tissues for intervertebral disc and meniscus tissue engineering.

  9. Carbonic anhydrase IX inhibition affects viability of cancer cells adapted to extracellular acidosis.

    Science.gov (United States)

    Andreucci, Elena; Peppicelli, Silvia; Carta, Fabrizio; Brisotto, Giulia; Biscontin, Eva; Ruzzolini, Jessica; Bianchini, Francesca; Biagioni, Alessio; Supuran, Claudiu T; Calorini, Lido

    2017-12-01

    Among the players of the adaptive response of cancer cells able to promote a resistant and aggressive phenotype, carbonic anhydrase IX (CAIX) recently has emerged as one of the most relevant drug targets. Indeed, CAIX targeting has received a lot of interest, and selective inhibitors are currently under clinical trials. Hypoxia has been identified as the master inductor of CAIX, but, to date, very few is known about the influence that another important characteristic of tumor microenvironment, i.e., extracellular acidosis, exerts on CAIX expression and activity. In the last decades, acidic microenvironment has been associated with aggressive tumor phenotype endowed with epithelial-to-mesenchymal transition (EMT) profile, high invasive and migratory ability, apoptosis, and drug resistance. We demonstrated that melanoma, breast, and colorectal cancer cells transiently and chronically exposed to acidified medium (pH 6.7 ± 0.1) showed a significantly increased CAIX expression compared to those grown in standard conditions (pH 7.4 ± 0.1). Moreover, we observed that the CAIX inhibitor FC16-670A (also named SLC-0111, which just successfully ended phase I clinical trials) not only prevents such increased expression under acidosis but also promotes apoptotic and necrotic programs only in acidified cancer cells. Thus, CAIX could represent a selective target of acidic cancer cells and FC16-670A inhibitor as a useful tool to affect this aggressive subpopulation characterized by conventional therapy escape. Cancer cells overexpress CAIX under transient and chronic extracellular acidosis. Acidosis-induced CAIX overexpression is NF-κB mediated and HIF-1α independent. FC16-670A prevents CAIX overexpression and induces acidified cancer cell death.

  10. Extracellular matrix metalloproteinase inducer (EMMPRIN) remodels the extracellular matrix through enhancing matrix metalloproteinases (MMPs) and inhibiting tissue inhibitors of MMPs expression in HPV-positive cervical cancer cells.

    Science.gov (United States)

    Xu, Q; Cao, X; Pan, J; Ye, Y; Xie, Y; Ohara, N; Ji, H

    2015-01-01

    PUPOSE OF INVESTIGATION: To study the expression of extracellular matrix metalloproteinase inducer (EMMPRIN), matrix metalloproteinases (MMPs), and tissue inhibitors of MMP (TIMPs) in uterine cervical cancer cell lines in vitro. EMMPRIN, MMPs, and TIMPs expression were assessed by Western blot and real-time RT-PCR from cervical carcinoma SiHa, HeLa, and C33-A cells. EMMPRIN recombinant significantly increased MMP-2, MMP-9 protein and mRNA expression in SiHa and Hela cells, but not in C33-A cells by Western blot analysis and real-time RT-PCR. EMMPRIN recombinant significantly inhibited TIMP-1 protein and mRNA levels in SiHa and Hela cells, but not in C33-A cells. There was no difference on the TIMP-2 expression in those cells with the treatment of EMMPRIN recombinant. EMMPRIN RNAi decreased MMP-2 and MMP-9 and increased TIMP-1 expression in SiHa and HeLa cells, but not in C33-A cells. There was no change on the expression of TIMP-2 mRNA levels in SiHa, HeLa and C33-A cells transfected with siEMMPRIN. EMMPRIN may induce MMP-2 and MMP-9, and downregulate TIMP-1 in HPV-positive cervical cancer cells in vitro.

  11. Fibronectin distribution in the extracellular matrix in the cells grown in deuterated media

    International Nuclear Information System (INIS)

    Buzgariu, Wanda; Caloianu, Maria; Moldovan, Lucia; Stefanescu, I.; Titescu, Gh.

    2003-01-01

    The aim of this work is the study of the influence of deuterated water upon the synthesis and organization of fibronectin (FN) in extracellular matrices. Changes were evidenced at the level of extracellular matrix in case of embryo fibroblast cultivation in media with different concentrations of heavy water (20%, 40% and 65%). FN was identified in the extracellular matrix by means of indirect immunocytochemical technique, using a secondary antibody coupled with peroxydase. In the presence of heavy water in culture medium, the arrangement and localization of cellular FN showed changes depending on the exposure time, D 2 O concentration in the medium and the FN polymerization step in the extra cellular matrix in correlation with the culture stage of the monolayer. The heavy water determined a strong reduction of the FN amount released by the cells. This reduction was most evident in the 65% D 2 O medium following a 5 day exposure. The FN distribution after 2 day exposure in an early stage with regards to the FN network formation in a the deuterated medium presented a FN pericellular distribution arranged in aggregates. The heavy water can act upon formation of FN fibrils immediately due to solvent role in the FN polymerization process but also indirectly through metabolic processes and so upon the protein synthesis and FN cellular secretion.The FN network arrangement in the cells cultivated in deuterated media as aggregates might be the effect of solvent role played by D 2 O while the quantitative reduction of FN results from perturbation of protein synthesis as well from biochemical synthesis reactions

  12. The effect of isochoric freezing on mammalian cells in an extracellular phosphate buffered solution.

    Science.gov (United States)

    Preciado, J; Rubinsky, B

    2018-04-20

    Isochoric (constant volume) freezing has been recently suggested as a new method for cell and organ preservation. As a first step in studying the effect of isochoric freezing on mammalian cells, Madin-Darby canine kidney epithelial cells (MDCK), were frozen in an isochoric system, in a simple extracellular phosphate buffered solution to -10 °C (96.5 MPa), - 15 °C (162 MPa) and -20 °C (205 MPa) for 60 and 120 min. Cell membrane integrity and cell metabolism were studied with a Live/Dead cell vitality assay and flow cytometry. We found that cell survival decreases with an increase in pressure (lower temperatures) and time of exposure. For example, 60% of cells survived 60 min at - 10 °C and only 18% survived 120 min at this temperature. Negligible survival was measured at - 20 °C. This study may serve as the baseline towards further research on techniques to optimize the effects of isochoric freezing on living biological matter. Copyright © 2018. Published by Elsevier Inc.

  13. Biological conduits combining bone marrow mesenchymal stem cells and extracellular matrix to treat long-segment sciatic nerve defects

    Directory of Open Access Journals (Sweden)

    Yang Wang

    2015-01-01

    Full Text Available The transplantation of polylactic glycolic acid conduits combining bone marrow mesenchymal stem cells and extracellular matrix gel for the repair of sciatic nerve injury is effective in some respects, but few data comparing the biomechanical factors related to the sciatic nerve are available. In the present study, rabbit models of 10-mm sciatic nerve defects were prepared. The rabbit models were repaired with autologous nerve, a polylactic glycolic acid conduit + bone marrow mesenchymal stem cells, or a polylactic glycolic acid conduit + bone marrow mesenchymal stem cells + extracellular matrix gel. After 24 weeks, mechanical testing was performed to determine the stress relaxation and creep parameters. Following sciatic nerve injury, the magnitudes of the stress decrease and strain increase at 7,200 seconds were largest in the polylactic glycolic acid conduit + bone marrow mesenchymal stem cells + extracellular matrix gel group, followed by the polylactic glycolic acid conduit + bone marrow mesenchymal stem cells group, and then the autologous nerve group. Hematoxylin-eosin staining demonstrated that compared with the polylactic glycolic acid conduit + bone marrow mesenchymal stem cells group and the autologous nerve group, a more complete sciatic nerve regeneration was found, including good myelination, regularly arranged nerve fibers, and a completely degraded and resorbed conduit, in the polylactic glycolic acid conduit + bone marrow mesenchymal stem cells + extracellular matrix gel group. These results indicate that bridging 10-mm sciatic nerve defects with a polylactic glycolic acid conduit + bone marrow mesenchymal stem cells + extracellular matrix gel construct increases the stress relaxation under a constant strain, reducing anastomotic tension. Large elongations under a constant physiological load can limit the anastomotic opening and shift, which is beneficial for the regeneration and functional reconstruction of sciatic nerve. Better

  14. Influence of the extracellular matrix on endogenous and transplanted stem cells after brain damage

    Directory of Open Access Journals (Sweden)

    Lars eRoll

    2014-08-01

    Full Text Available The limited regeneration capacity of the adult central nervous system requires strategies to improve recovery of patients. In this context, the interaction of endogenous as well as transplanted stem cells with their environment is crucial. An understanding of the molecular mechanisms could help to improve regeneration by targeted manipulation.In the course of reactive gliosis, astrocytes upregulate Glial fibrillary acidic protein (GFAP and start, in many cases, to proliferate. Beside GFAP, subpopulations of these astroglial cells coexpress neural progenitor markers like Nestin. Although cells express these markers, the proportion of cells that eventually give rise to neurons is limited in many cases in vivo compared to the situation in vitro. In the first section, we present the characteristics of endogenous progenitor-like cells and discuss the differences in their neurogenic potential in vitro and in vivo.As the environment plays an important role for survival, proliferation, migration, and other processes, the second section of the review describes changes in the extracellular matrix (ECM, a complex network that contains numerous signaling molecules. It appears that signals in the damaged central nervous system lead to an activation and de-differentiation of astrocytes, but do not effectively promote neuronal differentiation of these cells. Factors that influence stem cells during development are upregulated in the damaged brain as part of an environment resembling a stem cell niche. We give a general description of the ECM composition, with focus on stem cell-associated factors like the glycoprotein Tenascin-C.Stem cell transplantation is considered as potential treatment strategy. Interaction of transplanted stem cells with the host environment is critical for the outcome of stem cell-based therapies. Possible mechanisms involving the ECM by which transplanted stem cells might improve recovery are discussed in the last section.

  15. Extracellular Vesicle-Associated Transitory Cell Wall Components and Their Impact on the Interaction of Fungi with Host Cells.

    Science.gov (United States)

    Nimrichter, Leonardo; de Souza, Marcio M; Del Poeta, Maurizio; Nosanchuk, Joshua D; Joffe, Luna; Tavares, Patricia de M; Rodrigues, Marcio L

    2016-01-01

    Classic cell wall components of fungi comprise the polysaccharides glucans and chitin, in association with glycoproteins and pigments. During the last decade, however, system biology approaches clearly demonstrated that the composition of fungal cell walls include atypical molecules historically associated with intracellular or membrane locations. Elucidation of mechanisms by which many fungal molecules are exported to the extracellular space suggested that these atypical components are transitorily located to the cell wall. The presence of extracellular vesicles (EVs) at the fungal cell wall and in culture supernatants of distinct pathogenic species suggested a highly functional mechanism of molecular export in these organisms. Thus, the passage of EVs through fungal cell walls suggests remarkable molecular diversity and, consequently, a potentially variable influence on the host antifungal response. On the basis of information derived from the proteomic characterization of fungal EVs from the yeasts Cryptoccocus neoformans and Candida albicans and the dimorphic fungi Histoplasma capsulatum and Paracoccidioides brasiliensis, our manuscript is focused on the clear view that the fungal cell wall is much more complex than previously thought.

  16. Influence of surfaces modified with biomimetic extracellular matrices on adhesion and proliferation of mesenchymal stem cells and osteosarcoma cells.

    Science.gov (United States)

    Cai, Rong; Kawazoe, Naoki; Chen, Guoping

    2015-02-01

    Preparation of surfaces modified with biomimetic extracellular matrices (ECMs) is important for investigation of the interaction between ECMs and cells. In the present study, surfaces modified with ECMs from normal somatic cells, stem cells and tumor cells were prepared by cell culture method. The ECMs derived from bone marrow-derived mesenchymal stem cells (MSCs), dermal fibroblasts (FBs), osteoblasts (OBs) and MG63 osteosarcoma cells were deposited on the surfaces of cell-culture polystyrene plates (TCPS). The ECMs from different cell types had different compositions. The effects of the ECM-deposited surfaces on the adhesion, spreading and proliferation of MSCs and MG63 human osteosarcoma cells were dependent on the type of both ECMs and cells. The surfaces deposited with ECMs from MSCs, FBs and OBs promoted cell adhesion more strongly than surfaces deposited with ECMs from MG63 cells and TCPS. Compared to TCPS, the ECM-deposited surfaces promoted proliferation of MSCs while they inhibited the proliferation of MG63 cells. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Comparative Proteomic Analysis of Supportive and Unsupportive Extracellular Matrix Substrates for Human Embryonic Stem Cell Maintenance*

    Science.gov (United States)

    Soteriou, Despina; Iskender, Banu; Byron, Adam; Humphries, Jonathan D.; Borg-Bartolo, Simon; Haddock, Marie-Claire; Baxter, Melissa A.; Knight, David; Humphries, Martin J.; Kimber, Susan J.

    2013-01-01

    Human embryonic stem cells (hESCs) are pluripotent cells that have indefinite replicative potential and the ability to differentiate into derivatives of all three germ layers. hESCs are conventionally grown on mitotically inactivated mouse embryonic fibroblasts (MEFs) or feeder cells of human origin. In addition, feeder-free culture systems can be used to support hESCs, in which the adhesive substrate plays a key role in the regulation of stem cell self-renewal or differentiation. Extracellular matrix (ECM) components define the microenvironment of the niche for many types of stem cells, but their role in the maintenance of hESCs remains poorly understood. We used a proteomic approach to characterize in detail the composition and interaction networks of ECMs that support the growth of self-renewing hESCs. Whereas many ECM components were produced by supportive and unsupportive MEF and human placental stromal fibroblast feeder cells, some proteins were only expressed in supportive ECM, suggestive of a role in the maintenance of pluripotency. We show that identified candidate molecules can support attachment and self-renewal of hESCs alone (fibrillin-1) or in combination with fibronectin (perlecan, fibulin-2), in the absence of feeder cells. Together, these data highlight the importance of specific ECM interactions in the regulation of hESC phenotype and provide a resource for future studies of hESC self-renewal. PMID:23658023

  18. Extracellular matrix-dependent myosin dynamics during G1-S phase cell cycle progression in hepatocytes

    International Nuclear Information System (INIS)

    Bhadriraju, Kiran; Hansen, Linda K.

    2004-01-01

    Cell spreading and proliferation are tightly coupled in anchorage-dependent cells. While adhesion-dependent proliferation signals require an intact actin cytoskeleton, and some of these signals such as ERK activation have been characterized, the role of myosin in spreading and cell cycle progression under different extracellular matrix (ECM) conditions is not known. Studies presented here examine changes in myosin activity in freshly isolated hepatocytes under ECM conditions that promote either proliferation (high fibronectin density) or growth arrest (low fibronectin density). Three different measures were obtained and related to both spreading and cell cycle progression: myosin protein levels and association with cytoskeleton, myosin light chain phosphorylation, and its ATPase activity. During the first 48 h in culture, corresponding with transit through G1 phase, there was a six-fold increase in both myosin protein levels and myosin association with actin cytoskeleton. There was also a steady increase in myosin light chain phosphorylation and ATPase activity with spreading, which did not occur in non-spread, growth-arrested cells on low density of fibronectin. Myosin-inhibiting drugs blocked ERK activation, cyclin D1 expression, and S phase entry. Overexpression of the cell cycle protein cyclin D1 overcame both ECM-dependent and actomyosin-dependent inhibition of DNA synthesis, suggesting that cyclin D1 is a key event downstream of myosin-dependent cell cycle regulation

  19. Display of GPI-anchored anti-EGFR nanobodies on extracellular vesicles promotes tumour cell targeting

    Directory of Open Access Journals (Sweden)

    Sander A. A. Kooijmans

    2016-03-01

    Full Text Available Background: Extracellular vesicles (EVs are attractive candidate drug delivery systems due to their ability to functionally transport biological cargo to recipient cells. However, the apparent lack of target cell specificity of exogenously administered EVs limits their therapeutic applicability. In this study, we propose a novel method to equip EVs with targeting properties, in order to improve their interaction with tumour cells. Methods: EV producing cells were transfected with vectors encoding for anti-epidermal growth factor receptor (EGFR nanobodies, which served as targeting ligands for tumour cells, fused to glycosylphosphatidylinositol (GPI anchor signal peptides derived from decay-accelerating factor (DAF. EVs were isolated using ultrafiltration/size-exclusion liquid chromatography and characterized using western blotting, Nanoparticle Tracking Analysis, and electron microscopy. EV–tumour cell interactions were analyzed under static conditions using flow cytometry and under flow conditions using a live-cell fluorescence microscopy-coupled perfusion system. Results: V analysis showed that GPI-linked nanobodies were successfully displayed on EV surfaces and were highly enriched in EVs compared with parent cells. Display of GPI-linked nanobodies on EVs did not alter general EV characteristics (i.e. morphology, size distribution and protein marker expression, but greatly improved EV binding to tumour cells dependent on EGFR density under static conditions. Moreover, nanobody-displaying EVs showed a significantly improved cell association to EGFR-expressing tumour cells under flow conditions. Conclusions: We show that nanobodies can be anchored on the surface of EVs via GPI, which alters their cell targeting behaviour. Furthermore, this study highlights GPI-anchoring as a new tool in the EV toolbox, which may be applied for EV display of a variety of proteins, such as antibodies, reporter proteins and signaling molecules.

  20. Extracellular vesicle-mediated phenotype switching in malignant and non-malignant colon cells

    International Nuclear Information System (INIS)

    Mulvey, Hillary E.; Chang, Audrey; Adler, Jason; Del Tatto, Michael; Perez, Kimberly; Quesenberry, Peter J.; Chatterjee, Devasis

    2015-01-01

    Extracellular vesicles (EVs) are secreted from many cells, carrying cargoes including proteins and nucleic acids. Research has shown that EVs play a role in a variety of biological processes including immunity, bone formation and recently they have been implicated in promotion of a metastatic phenotype. EVs were isolated from HCT116 colon cancer cells, 1459 non-malignant colon fibroblast cells, and tumor and normal colon tissue from a patient sample. Co-cultures were performed with 1459 cells and malignant vesicles, as well as HCT116 cells and non-malignant vesicles. Malignant phenotype was measured using soft agar colony formation assay. Co-cultures were also analyzed for protein levels using mass spectrometry. The importance of 14-3-3 zeta/delta in transfer of malignant phenotype was explored using siRNA. Additionally, luciferase reporter assay was used to measure the transcriptional activity of NF-κB. This study demonstrates the ability of EVs derived from malignant colon cancer cell line and malignant patient tissue to induce the malignant phenotype in non-malignant colon cells. Similarly, EVs derived from non-malignant colon cell lines and normal patient tissue reversed the malignant phenotype of HCT116 cells. Cells expressing an EV-induced malignant phenotype showed increased transcriptional activity of NF-κB which was inhibited by the NF--κB inhibitor, BAY117082. We also demonstrate that knock down of 14-3-3 zeta/delta reduced anchorage-independent growth of HCT116 cells and 1459 cells co-cultured with HCT derived EVs. Evidence of EV-mediated induction of malignant phenotype, and reversal of malignant phenotype, provides rational basis for further study of the role of EVs in tumorigenesis. Identification of 14-3-3 zeta/delta as up-regulated in malignancy suggests its potential as a putative drug target for the treatment of colorectal cancer

  1. Characterization of rat primary trigeminal satellite glial cells and associated extracellular vesicles under normal and inflammatory conditions

    DEFF Research Database (Denmark)

    Vinterhøj, Hye Sook Han; Stensballe, Allan; Duroux, Meg

    2018-01-01

    Satellite glial cells (SGCs) in sensory ganglia contribute to the pathogenesis of chronic pain, potentially through mediating extracellular or paracrine signaling. Recently, extracellular vesicles (EVs) in the form of exosomes have been found to play an important role in cell-cell communication....... Results demonstrated that SGCs shed vesicles in the size range of exosomes (>150 nm) but with altered protein expression upon LPS-activation. Proteomic profiling of SGCs-shed EVs showed that a number of proteins were differentially regulated upon LPS stimulation such as junction plakoglobin and myosin 9...

  2. Involvement of extracellular factors in maintaining self-renewal of neural stem cell by nestin.

    Science.gov (United States)

    Di, Chun Guang; Xiang, Andy Peng; Jia, Lei; Liu, Jun Feng; Lahn, Bruce T; Ma, Bao Feng

    2014-07-09

    Nestin knockout leads to embryonic lethality and self-renewal deficiency in neural stem cells (NSCs). However, how nestin maintains self-renewal remains uncertain. Here, we used the dosage effect of nestin in heterozygous mice (Nes+/-) to study self-renewal of NSCs. With existing extracellular signaling in vivo or in vitro, nestin levels do not affect proliferation ability or apoptosis when compared between Nes+/- and Nes+/+ NSCs. However, self-renewal ability of Nes+/- NSCs is impaired when plated at a low cell density and completely lost at a clonal density. This deficiency in self-renewal at a clonal density is rescued using a medium conditioned by Nes+/+ NSCs. In addition, the Akt signaling pathway is altered at low density and reversed by conditioned medium. Our data show that secreted factors contribute toward maintaining self-renewal of NSCs by nestin, potentially through Akt signaling.

  3. High fidelity visualization of cell-to-cell variation and temporal dynamics in nascent extracellular matrix formation.

    Science.gov (United States)

    McLeod, Claire M; Mauck, Robert L

    2016-12-12

    Extracellular matrix dynamics are key to tissue morphogenesis, homeostasis, injury, and repair. The spatiotemporal organization of this matrix has profound biological implications, but is challenging to monitor using standard techniques. Here, we address these challenges by using noncanonical amino acid tagging to fluorescently label extracellular matrix synthesized in the presence of bio-orthogonal methionine analogs. This strategy labels matrix proteins with high resolution, without compromising their distribution or mechanical function. We demonstrate that the organization and temporal dynamics of the proteinaceous matrix depend on the biophysical features of the microenvironment, including the biomaterial scaffold and the niche constructed by cells themselves. Pulse labeling experiments reveal that, in immature constructs, nascent matrix is highly fibrous and interdigitates with pre-existing matrix, while in more developed constructs, nascent matrix lacks fibrous organization and is retained in the immediate pericellular space. Inhibition of collagen crosslinking increases matrix synthesis, but compromises matrix organization. Finally, these data demonstrate marked cell-to-cell heterogeneity amongst both chondrocytes and mesenchymal stem cells undergoing chondrogenesis. Collectively, these results introduce fluorescent noncanonical amino acid tagging as a strategy to investigate spatiotemporal matrix organization, and demonstrate its ability to identify differences in phenotype, microenvironment, and matrix assembly at the single cell level.

  4. Evaluation of the damage of cell wall and cell membrane for various extracellular polymeric substance extractions of activated sludge.

    Science.gov (United States)

    Guo, Xuesong; Liu, Junxin; Xiao, Benyi

    2014-10-20

    Extracellular polymeric substances (EPS) are susceptible to contamination by intracellular substances released during the extraction of EPS owing to the damage caused to microbial cell structures. The damage to cell walls and cell membranes in nine EPS extraction processes of activated sludge was evaluated in this study. The extraction of EPS (including proteins, carbohydrates and DNA) was the highest using the NaOH extraction method and the lowest using formaldehyde extraction. All nine EPS extraction methods in this study resulted in cell wall and membrane damage. The damage to cell walls, evaluated by 2-keto-3-deoxyoctonate (KDO) and N-acetylglucosamine content changes in extracted EPS, was the most significant in the NaOH extraction process. Formaldehyde extraction showed a similar extent of damage to cell walls to those detected in the control method (centrifugation), while those in the formaldehyde-NaOH and cation exchange resin extractions were slightly higher than those detected in the control. N-acetylglucosamine was more suitable than KDO for the evaluation of cell wall damage in the EPS extraction of activated sludge. The damage to cell membranes was characterized by two fluorochromes (propidium iodide and FITC Annexin V) with flow cytometry (FCM) measurement. The highest proportion of membrane-damaged cells was detected in NaOH extraction (26.54% of total cells) while membrane-damaged cells comprised 8.19% of total cells in the control. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Extracellular mass transport considerations for space flight research concerning suspended and adherent in vitro cell cultures.

    Science.gov (United States)

    Klaus, David M; Benoit, Michael R; Nelson, Emily S; Hammond, Timmothy G

    2004-03-01

    Conducting biological research in space requires consideration be given to isolating appropriate control parameters. For in vitro cell cultures, numerous environmental factors can adversely affect data interpretation. A biological response attributed to microgravity can, in theory, be explicitly correlated to a specific lack of weight or gravity-driven motion occurring to, within or around a cell. Weight can be broken down to include the formation of hydrostatic gradients, structural load (stress) or physical deformation (strain). Gravitationally induced motion within or near individual cells in a fluid includes sedimentation (or buoyancy) of the cell and associated shear forces, displacement of cytoskeleton or organelles, and factors associated with intra- or extracellular mass transport. Finally, and of particular importance for cell culture experiments, the collective effects of gravity must be considered for the overall system consisting of the cells, their environment and the device in which they are contained. This does not, however, rule out other confounding variables such as launch acceleration, on orbit vibration, transient acceleration impulses or radiation, which can be isolated using onboard centrifuges or vibration isolation techniques. A framework is offered for characterizing specific cause-and-effect relationships for gravity-dependent responses as a function of the above parameters.

  6. Ornithine decarboxylase and extracellular polyamines regulate microvascular sprouting and actin cytoskeleton dynamics in endothelial cells

    International Nuclear Information System (INIS)

    Kucharzewska, Paulina; Welch, Johanna E.; Svensson, Katrin J.; Belting, Mattias

    2010-01-01

    The polyamines are essential for cancer cell proliferation during tumorigenesis. Targeted inhibition of ornithine decarboxylase (ODC), i.e. a key enzyme of polyamine biosynthesis, by α-difluoromethylornithine (DFMO) has shown anti-neoplastic activity in various experimental models. This activity has mainly been attributed to the anti-proliferative effect of DFMO in cancer cells. Here, we provide evidence that unperturbed ODC activity is a requirement for proper microvessel sprouting ex vivo as well as the migration of primary human endothelial cells. DFMO-mediated ODC inhibition was reversed by extracellular polyamine supplementation, showing that anti-angiogenic effects of DFMO were specifically related to polyamine levels. ODC inhibition was associated with an abnormal morphology of the actin cytoskeleton during cell spreading and migration. Moreover, our data suggest that de-regulated actin cytoskeleton dynamics in DFMO treated endothelial cells may be related to constitutive activation of the small GTPase CDC42, i.e. a well-known regulator of cell motility and actin cytoskeleton remodeling. These insights into the potential role of polyamines in angiogenesis should stimulate further studies testing the combined anti-tumor effect of polyamine inhibition and established anti-angiogenic therapies in vivo.

  7. Wnt interaction and extracellular release of prominin-1/CD133 in human malignant melanoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Rappa, Germana [Cancer Research Program, Roseman University of Health Sciences, 10530 Discovery Drive. Las Vegas, NV 89135 (United States); College of Pharmacy, Roseman University of Health Sciences, Henderson, NV 89104 (United States); Mercapide, Javier; Anzanello, Fabio [Cancer Research Program, Roseman University of Health Sciences, 10530 Discovery Drive. Las Vegas, NV 89135 (United States); Le, Thuc T. [Nevada Cancer Institute, Las Vegas, NV 89135 (United States); Johlfs, Mary G. [Cancer Research Program, Roseman University of Health Sciences, 10530 Discovery Drive. Las Vegas, NV 89135 (United States); Center for Diabetes and Obesity Prevention, Treatment, Research and Education, Roseman University of Health Sciences, Henderson, NV 89104 (United States); Fiscus, Ronald R. [Cancer Research Program, Roseman University of Health Sciences, 10530 Discovery Drive. Las Vegas, NV 89135 (United States); College of Pharmacy, Roseman University of Health Sciences, Henderson, NV 89104 (United States); Center for Diabetes and Obesity Prevention, Treatment, Research and Education, Roseman University of Health Sciences, Henderson, NV 89104 (United States); Wilsch-Bräuninger, Michaela [Max-Planck-Institute of Molecular Cell Biology and Genetics, Pfotenhauerstr. 108, 01307 Dresden (Germany); Corbeil, Denis [Tissue Engineering Laboratories (BIOTEC) and DFG Research Center and Cluster of Excellence for Regenerative Therapies Dresden (CRTD), Technische Universität Dresden, Tatzberg 47–49, 01307 Dresden, Germany Technische Universitat Dresden, Dresden (Germany); Lorico, Aurelio, E-mail: alorico@roseman.edu [Cancer Research Program, Roseman University of Health Sciences, 10530 Discovery Drive. Las Vegas, NV 89135 (United States); College of Pharmacy, Roseman University of Health Sciences, Henderson, NV 89104 (United States)

    2013-04-01

    Prominin-1 (CD133) is the first identified gene of a novel class of pentaspan membrane glycoproteins. It is expressed by various epithelial and non-epithelial cells, and notably by stem and cancer stem cells. In non-cancerous cells such as neuro-epithelial and hematopoietic stem cells, prominin-1 is selectively concentrated in plasma membrane protrusions, and released into the extracellular milieu in association with small vesicles. Previously, we demonstrated that prominin-1 contributes to melanoma cells pro-metastatic properties and suggested that it may constitute a molecular target to prevent prominin-1-expressing melanomas from colonizing and growing in lymph nodes and distant organs. Here, we report that three distinct pools of prominin-1 co-exist in cultures of human FEMX-I metastatic melanoma. Morphologically, in addition to the plasma membrane localization, prominin-1 is found within the intracellular compartments, (e.g., Golgi apparatus) and in association with extracellular membrane vesicles. The latter prominin-1–positive structures appeared in three sizes (small, ≤40 nm; intermediates ∼40–80 nm, and large, >80 nm). Functionally, the down-regulation of prominin-1 in FEMX-I cells resulted in a significant reduction of number of lipid droplets as observed by coherent anti-Stokes Raman scattering image analysis and Oil red O staining, and surprisingly in a decrease in the nuclear localization of beta-catenin, a surrogate marker of Wnt activation. Moreover, the T-cell factor/lymphoid enhancer factor (TCF/LEF) promoter activity was 2 to 4 times higher in parental than in prominin-1-knockdown cells. Collectively, our results point to Wnt signaling and/or release of prominin-1–containing membrane vesicles as mediators of the pro-metastatic activity of prominin-1 in FEMX-I melanoma. - Highlights: ► First report of release of prominin-1–containing microvesicles from cancer cells. ► Pro-metastatic role of prominin-1–containing microvesicles in

  8. Wnt interaction and extracellular release of prominin-1/CD133 in human malignant melanoma cells

    International Nuclear Information System (INIS)

    Rappa, Germana; Mercapide, Javier; Anzanello, Fabio; Le, Thuc T.; Johlfs, Mary G.; Fiscus, Ronald R.; Wilsch-Bräuninger, Michaela; Corbeil, Denis; Lorico, Aurelio

    2013-01-01

    Prominin-1 (CD133) is the first identified gene of a novel class of pentaspan membrane glycoproteins. It is expressed by various epithelial and non-epithelial cells, and notably by stem and cancer stem cells. In non-cancerous cells such as neuro-epithelial and hematopoietic stem cells, prominin-1 is selectively concentrated in plasma membrane protrusions, and released into the extracellular milieu in association with small vesicles. Previously, we demonstrated that prominin-1 contributes to melanoma cells pro-metastatic properties and suggested that it may constitute a molecular target to prevent prominin-1-expressing melanomas from colonizing and growing in lymph nodes and distant organs. Here, we report that three distinct pools of prominin-1 co-exist in cultures of human FEMX-I metastatic melanoma. Morphologically, in addition to the plasma membrane localization, prominin-1 is found within the intracellular compartments, (e.g., Golgi apparatus) and in association with extracellular membrane vesicles. The latter prominin-1–positive structures appeared in three sizes (small, ≤40 nm; intermediates ∼40–80 nm, and large, >80 nm). Functionally, the down-regulation of prominin-1 in FEMX-I cells resulted in a significant reduction of number of lipid droplets as observed by coherent anti-Stokes Raman scattering image analysis and Oil red O staining, and surprisingly in a decrease in the nuclear localization of beta-catenin, a surrogate marker of Wnt activation. Moreover, the T-cell factor/lymphoid enhancer factor (TCF/LEF) promoter activity was 2 to 4 times higher in parental than in prominin-1-knockdown cells. Collectively, our results point to Wnt signaling and/or release of prominin-1–containing membrane vesicles as mediators of the pro-metastatic activity of prominin-1 in FEMX-I melanoma. - Highlights: ► First report of release of prominin-1–containing microvesicles from cancer cells. ► Pro-metastatic role of prominin-1–containing microvesicles in

  9. Proliferation and extracellular matrix synthesis of smooth muscle cells cultured from human coronary atherosclerotic and restenotic lesions

    NARCIS (Netherlands)

    D.C. MacLeod (Donald); B.H. Strauss (Bradley); J. Escaned (Javier); V.A.W.M. Umans (Victor); R-J. van Suylen (Robert-Jan); A. Verkerk (Anton); P.J. de Feyter (Pim); P.W.J.C. Serruys (Patrick); M. de Jong (Marcel)

    1994-01-01

    textabstractOBJECTIVES. The purpose of this study was to examine the proliferative capacity and extracellular matrix synthesis of human coronary plaque cells in vitro. BACKGROUND. Common to both primary atherosclerosis and restenosis are vascular smooth muscle cell proliferation and production of

  10. Fibroblast-Derived Extracellular Matrices: An Alternative Cell Culture System That Increases Metastatic Cellular Properties.

    Directory of Open Access Journals (Sweden)

    Michael T Scherzer

    Full Text Available Poor survival rates from lung cancer can largely be attributed to metastatic cells that invade and spread throughout the body. The tumor microenvironment (TME is composed of multiple cell types, as well as non-cellular components. The TME plays a critical role in the development of metastatic cancers by providing migratory cues and changing the properties of the tumor cells. The Extracellular Matrix (ECM, a main component of the TME, has been shown to change composition during tumor progression, contributing to cancer cell invasion and survival away from the primary cancer site. Although the ECM is well-known to influence the fate of tumor progression, little is known about the molecular mechanisms that are affected by the cancer cell-ECM interactions. It is imperative that these mechanisms are elucidated in order to properly understand and prevent lung cancer dissemination. However, common in vitro studies do not incorporate these interactions into everyday cell culture assays. We have adopted a model that examines decellularized human fibroblast-derived ECM as a 3-dimensional substrate for growth of lung adenocarcinoma cell lines. Here, we have characterized the effect of fibroblast-derived matrices on the properties of various lung-derived epithelial cell lines, including cancerous and non-transformed cells. This work highlights the significance of the cell-ECM interaction and its requirement for incorporation into in vitro experiments. Implementation of a fibroblast-derived ECM as an in vitro technique will provide researchers with an important factor to manipulate to better recreate and study the TME.

  11. Cell adhesion control by ion implantation into extra-cellular matrix

    International Nuclear Information System (INIS)

    Suzuki, Yoshiaki; Kusakabe, Masahiro; Kaibara, Makoto; Iwaki, Masaya; Sasabe, Hiroyuki; Nishisaka, Tsuyoshi

    1994-01-01

    Cell adhesion control of polymer surfaces by ion implantation into polymers and extra-cellular matrix has been studied by means of in vitro adhesion measurements of the carcinoma of the cervix (HeLa cell). The specimens used were polystyrene (PS), oxygen plasma treated polystyrene (PS-O), extra-cellular matrix (Collagen: Type I) coated polystyrene (PS-C), and gelatin coated polystyrene (PS-G). Ne + , Na + , and Ar + implantations were performed with a fluence of 1x10 15 ions/cm 2 at energies of 50, 100 and 150 keV. The chemical and physical structures of ion implanted specimens have been investigated by Fourier transform infrared spectroscopy (FT-IR-ATR), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. Ion implanted PS demonstrated a dramatic improvement of adhesion of HeLa cell. HeLa cell adhered only to ion implanted circular domains of a diameter about 0.1 mm on PS. By contrast, ion implanted PS-C, PS-G and PS-O domains inhibited the cell adhesion. These phenomena were observed on Ne + , Na + , and Ar + implanted specimens at energies of 50, 100, and 150 keV. Ion implantation broke the original chemical bonds to form new radicals such as =C=O, condensed rings, C-C, C-O and OH radical. Ion implanted PS had a large amount of new radicals compared with that of PS-C, PS-G and PS-O. Ion implantation broke NH and NH 3 bonds originating from amino acid in PS-C and PS-G. OH and =C=O caused by oxygen treatment in PS-O were also destroyed by ion implantation. It is concluded that cell adhesion to ion implanted PS was caused by carbon structure and new radicals induced by ion implantation. The inhibition of HeLa cell adhesion on PS-C, PS-G and PS-O was caused by the destruction of cell adhesion properties of amino acid, OH and =C=O by radiation effects. ((orig.))

  12. Extracellular matrix collagen alters cell proliferation and cell cycle progression of human uterine leiomyoma smooth muscle cells.

    Science.gov (United States)

    Koohestani, Faezeh; Braundmeier, Andrea G; Mahdian, Arash; Seo, Jane; Bi, JiaJia; Nowak, Romana A

    2013-01-01

    Uterine leiomyomas (ULs) are benign tumors occurring in the majority of reproductive aged women. Despite the high prevalence of these tumors, little is known about their etiology. A hallmark of ULs is the excessive deposition of extracellular matrix (ECM), primarily collagens. Collagens are known to modulate cell behavior and function singularly or through interactions with integrins and growth factor-mediated mitogenic pathways. To better understand the pathogenesis of ULs and the role of ECM collagens in their growth, we investigated the interaction of leiomyoma smooth muscle cells (LSMCs) with two different forms of collagen, non-polymerized collagen (monomeric) and polymerized collagen (fibrillar), in the absence or presence of platelet-derived growth factor (PDGF), an abundant growth factor in ULs. Primary cultures of human LSMCS from symptomatic patients were grown on these two different collagen matrices and their morphology, cytoskeletal organization, cellular proliferation, and signaling pathways were evaluated. Our results showed that LSMCs had distinct morphologies on the different collagen matrices and their basal as well as PDGF-stimulated proliferation varied on these matrices. These differences in proliferation were accompanied by changes in cell cycle progression and p21, an inhibitory cell cycle protein. In addition we found alterations in the phosphorylation of focal adhesion kinase, cytoskeletal reorganization, and activation of the mitogen activated protein kinase (MAPK) signaling pathway. In conclusion, our results demonstrate a direct effect of ECM on the proliferation of LSMCs through interplay between the collagen matrix and the PDGF-stimulated MAPK pathway. In addition, these findings will pave the way for identifying novel therapeutic approaches for ULs that target ECM proteins and their signaling pathways in ULs.

  13. Thioredoxin is involved in endothelial cell extracellular transglutaminase 2 activation mediated by celiac disease patient IgA.

    Directory of Open Access Journals (Sweden)

    Cristina Antonella Nadalutti

    Full Text Available PURPOSE: To investigate the role of thioredoxin (TRX, a novel regulator of extracellular transglutaminase 2 (TG2, in celiac patients IgA (CD IgA mediated TG2 enzymatic activation. METHODS: TG2 enzymatic activity was evaluated in endothelial cells (HUVECs under different experimental conditions by ELISA and Western blotting. Extracellular TG2 expression was studied by ELISA and immunofluorescence. TRX was analysed by Western blotting and ELISA. Serum immunoglobulins class A from healthy subjects (H IgA were used as controls. Extracellular TG2 enzymatic activity was inhibited by R281. PX12, a TRX inhibitor, was also employed in the present study. RESULTS: We have found that in HUVECs CD IgA is able to induce the activation of extracellular TG2 in a dose-dependent manner. Particularly, we noted that the extracellular modulation of TG2 activity mediated by CD IgA occurred only under reducing conditions, also needed to maintain antibody binding. Furthermore, CD IgA-treated HUVECs were characterized by a slightly augmented TG2 surface expression which was independent from extracellular TG2 activation. We also observed that HUVECs cultured in the presence of CD IgA evinced decreased TRX surface expression, coupled with increased secretion of the protein into the culture medium. Intriguingly, inhibition of TRX after CD IgA treatment was able to overcome most of the CD IgA-mediated effects including the TG2 extracellular transamidase activity. CONCLUSIONS: Altogether our findings suggest that in endothelial cells CD IgA mediate the constitutive activation of extracellular TG2 by a mechanism involving the redox sensor protein TRX.

  14. Early Dysregulation of Cell Adhesion and Extracellular Matrix Pathways in Breast Cancer Progression

    Science.gov (United States)

    Emery, Lyndsey A.; Tripathi, Anusri; King, Chialin; Kavanah, Maureen; Mendez, Jane; Stone, Michael D.; de las Morenas, Antonio; Sebastiani, Paola; Rosenberg, Carol L.

    2009-01-01

    Proliferative breast lesions, such as simple ductal hyperplasia (SH) and atypical ductal hyperplasia (ADH), are candidate precursors to ductal carcinoma in situ (DCIS) and invasive cancer. To better understand the relationship of breast lesions to more advanced disease, we used microdissection and DNA microarrays to profile the gene expression of patient-matched histologically normal (HN), ADH, and DCIS from 12 patients with estrogen receptor positive sporadic breast cancer. SH were profiled from a subset of cases. We found 837 differentially expressed genes between DCIS-HN and 447 between ADH-HN, with >90% of the ADH-HN genes also present among the DCIS-HN genes. Only 61 genes were identified between ADH-DCIS. Expression differences were reproduced in an independent cohort of patient-matched lesions by quantitative real-time PCR. Many breast cancer-related genes and pathways were dysregulated in ADH and maintained in DCIS. Particularly, cell adhesion and extracellular matrix interactions were overrepresented. Focal adhesion was the top pathway in each gene set. We conclude that ADH and DCIS share highly similar gene expression and are distinct from HN. In contrast, SH appear more similar to HN. These data provide genetic evidence that ADH (but not SH) are often precursors to cancer and suggest cancer-related genetic changes, particularly adhesion and extracellular matrix pathways, are dysregulated before invasion and even before malignancy is apparent. These findings could lead to novel risk stratification, prevention, and treatment approaches. PMID:19700746

  15. Extracellular histones, cell-free DNA, or nucleosomes: differences in immunostimulation.

    Science.gov (United States)

    Marsman, Gerben; Zeerleder, Sacha; Luken, Brenda M

    2016-12-08

    In inflammation, extensive cell death may occur, which results in the release of chromatin components into the extracellular environment. Individually, the purified chromatin components double stranded (ds)DNA and histones have been demonstrated, both in vitro and in vivo, to display various immunostimulatory effects, for example, histones induce cytotoxicity and proinflammatory signaling through toll-like receptor (TLR)2 and 4, while DNA induces signaling through TLR9 and intracellular nucleic acid sensing mechanisms. However, DNA and histones are organized in nucleosomes in the nucleus, and evidence suggests that nucleosomes are released as such in inflammation. The cytotoxicity and proinflammatory signaling induced by nucleosomes have not been studied as extensively as the separate effects brought about by histones and dsDNA, and there appear to be some marked differences. Remarkably, little distinction between the different forms in which histones circulate has been made throughout literature. This is partly due to the limitations of existing techniques to differentiate between histones in their free or DNA-bound form. Here we review the current understanding of immunostimulation induced by extracellular histones, dsDNA and nucleosomes, and discuss the importance of techniques that in their detection differentiate between these different chromatin components.

  16. Neutrophil Extracellular DNA Traps Induce Autoantigen Production by Airway Epithelial Cells

    Directory of Open Access Journals (Sweden)

    Youngwoo Choi

    2017-01-01

    Full Text Available The hypothesis of autoimmune involvement in asthma has received much recent interest. Autoantibodies, such as anti-cytokeratin (CK 18, anti-CK19, and anti-α-enolase antibodies, react with self-antigens and are found at high levels in the sera of patients with severe asthma (SA. However, the mechanisms underlying autoantibody production in SA have not been fully determined. The present study was conducted to demonstrate that neutrophil extracellular DNA traps (NETs, cytotoxic molecules released from neutrophils, are a key player in the stimulation of airway epithelial cells (AECs to produce autoantigens. This study showed that NETs significantly increased the intracellular expression of tissue transglutaminase (tTG but did not affect that of CK18 in AECs. NETs induced the extracellular release of both tTG and CK18 in a concentration-dependent manner. Moreover, NETs directly degraded intracellular α-enolase into small fragments. However, antibodies against neutrophil elastase (NE or myeloperoxidase (MPO attenuated the effects of NETs on AECs. Furthermore, each NET isolated from healthy controls (HC, nonsevere asthma (NSA, and SA had different characteristics. Taken together, these findings suggest that AECs exposed to NETs may exhibit higher autoantigen production, especially in SA. Therefore, targeting of NETs may represent a new therapy for neutrophilic asthma with a high level of autoantigens.

  17. The regulation of growth and metabolism of kidney stem cell with regional specificity using extracellular matrix derived from kidney

    OpenAIRE

    O’Neill, John D.; Freytes, Donald O.; Anandappa, Annabelle; Oliver, Juan A.; Vunjak-Novakovic, Gordana

    2013-01-01

    Native extracellular matrix (ECM) that is secreted and maintained by resident cells is of great interest for cell culture and cell delivery. We hypothesized that specialized bioengineered niches for stem cells can be established using ECM-derived scaffolding materials. Kidney was selected as a model system because of the high regional diversification of renal tissue matrix. By preparing the ECM from three specialized regions of the kidney (cortex, medulla, and papilla; whole kidney, heart, an...

  18. Decellularized Tissue and Cell-Derived Extracellular Matrices as Scaffolds for Orthopaedic Tissue Engineering

    Science.gov (United States)

    Cheng, Christina W.; Solorio, Loran D.; Alsberg, Eben

    2014-01-01

    The reconstruction of musculoskeletal defects is a constant challenge for orthopaedic surgeons. Musculoskeletal injuries such as fractures, chondral lesions, infections and tumor debulking can often lead to large tissue voids requiring reconstruction with tissue grafts. Autografts are currently the gold standard in orthopaedic tissue reconstruction; however, there is a limit to the amount of tissue that can be harvested before compromising the donor site. Tissue engineering strategies using allogeneic or xenogeneic decellularized bone, cartilage, skeletal muscle, tendon and ligament have emerged as promising potential alternative treatment. The extracellular matrix provides a natural scaffold for cell attachment, proliferation and differentiation. Decellularization of in vitro cell-derived matrices can also enable the generation of autologous constructs from tissue specific cells or progenitor cells. Although decellularized bone tissue is widely used clinically in orthopaedic applications, the exciting potential of decellularized cartilage, skeletal muscle, tendon and ligament cell-derived matrices has only recently begun to be explored for ultimate translation to the orthopaedic clinic. PMID:24417915

  19. Measuring Bioenergetics in T Cells Using a Seahorse Extracellular Flux Analyzer.

    Science.gov (United States)

    van der Windt, Gerritje J W; Chang, Chih-Hao; Pearce, Erika L

    2016-04-01

    This unit contains several protocols to determine the energy utilization of T cells in real-time using a Seahorse Extracellular Flux Analyzer (http://www.seahorsebio.com). The advantages to using this machine over traditional metabolic assays include the simultaneous measurement of glycolysis and mitochondrial respiration, in real-time, on relatively small numbers of cells, without any radioactivity. The Basic Protocol describes a standard mitochondrial stress test on the XF(e) 96, which yields information about oxidative phosphorylation and glycolysis, two energy-generating pathways. The alternate protocols provide examples of adaptations to the Basic Protocol, including adjustments for the use of the XF(e) 24. A protocol for real-time bioenergetic responses to T cell activation allows for the analysis of immediate metabolic changes after T cell receptor stimulation. Specific substrate utilization can be determined by the use of differential assay media, or the injection of drugs that specifically affect certain metabolic processes. Accurate cell numbers, purity, and viability are critical to obtain reliable results. Copyright © 2016 John Wiley & Sons, Inc.

  20. Advances in the quantification of mitochondrial function in primary human immune cells through extracellular flux analysis.

    Directory of Open Access Journals (Sweden)

    Dequina Nicholas

    Full Text Available Numerous studies show that mitochondrial energy generation determines the effectiveness of immune responses. Furthermore, changes in mitochondrial function may regulate lymphocyte function in inflammatory diseases like type 2 diabetes. Analysis of lymphocyte mitochondrial function has been facilitated by introduction of 96-well format extracellular flux (XF96 analyzers, but the technology remains imperfect for analysis of human lymphocytes. Limitations in XF technology include the lack of practical protocols for analysis of archived human cells, and inadequate data analysis tools that require manual quality checks. Current analysis tools for XF outcomes are also unable to automatically assess data quality and delete untenable data from the relatively high number of biological replicates needed to power complex human cell studies. The objectives of work presented herein are to test the impact of common cellular manipulations on XF outcomes, and to develop and validate a new automated tool that objectively analyzes a virtually unlimited number of samples to quantitate mitochondrial function in immune cells. We present significant improvements on previous XF analyses of primary human cells that will be absolutely essential to test the prediction that changes in immune cell mitochondrial function and fuel sources support immune dysfunction in chronic inflammatory diseases like type 2 diabetes.

  1. ALS Pathogenesis and Therapeutic Approaches: The Role of Mesenchymal Stem Cells and Extracellular Vesicles.

    Science.gov (United States)

    Bonafede, Roberta; Mariotti, Raffaella

    2017-01-01

    Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by progressive muscle paralysis determined by the degeneration of motoneurons in the motor cortex brainstem and spinal cord. The ALS pathogenetic mechanisms are still unclear, despite the wealth of studies demonstrating the involvement of several altered signaling pathways, such as mitochondrial dysfunction, glutamate excitotoxicity, oxidative stress and neuroinflammation. To date, the proposed therapeutic strategies are targeted to one or a few of these alterations, resulting in only a minimal effect on disease course and survival of ALS patients. The involvement of different mechanisms in ALS pathogenesis underlines the need for a therapeutic approach targeted to multiple aspects. Mesenchymal stem cells (MSC) can support motoneurons and surrounding cells, reduce inflammation, stimulate tissue regeneration and release growth factors. On this basis, MSC have been proposed as promising candidates to treat ALS. However, due to the drawbacks of cell therapy, the possible therapeutic use of extracellular vesicles (EVs) released by stem cells is raising increasing interest. The present review summarizes the main pathological mechanisms involved in ALS and the related therapeutic approaches proposed to date, focusing on MSC therapy and their preclinical and clinical applications. Moreover, the nature and characteristics of EVs and their role in recapitulating the effect of stem cells are discussed, elucidating how and why these vesicles could provide novel opportunities for ALS treatment.

  2. Potentiation of NMDA receptor-dependent cell responses by extracellular high mobility group box 1 protein.

    Directory of Open Access Journals (Sweden)

    Marco Pedrazzi

    Full Text Available BACKGROUND: Extracellular high mobility group box 1 (HMGB1 protein can operate in a synergistic fashion with different signal molecules promoting an increase of cell Ca(2+ influx. However, the mechanisms responsible for this effect of HMGB1 are still unknown. PRINCIPAL FINDINGS: Here we demonstrate that, at concentrations of agonist per se ineffective, HMGB1 potentiates the activation of the ionotropic glutamate N-methyl-D-aspartate receptor (NMDAR in isolated hippocampal nerve terminals and in a neuroblastoma cell line. This effect was abolished by the NMDA channel blocker MK-801. The HMGB1-facilitated NMDAR opening was followed by activation of the Ca(2+-dependent enzymes calpain and nitric oxide synthase in neuroblastoma cells, resulting in an increased production of NO, a consequent enhanced cell motility, and onset of morphological differentiation. We have also identified NMDAR as the mediator of HMGB1-stimulated murine erythroleukemia cell differentiation, induced by hexamethylenebisacetamide. The potentiation of NMDAR activation involved a peptide of HMGB1 located in the B box at the amino acids 130-139. This HMGB1 fragment did not overlap with binding sites for other cell surface receptors of HMGB1, such as the advanced glycation end products or the Toll-like receptor 4. Moreover, in a competition assay, the HMGB1((130-139 peptide displaced the NMDAR/HMGB1 interaction, suggesting that it comprised the molecular and functional site of HMGB1 regulating the NMDA receptor complex. CONCLUSION: We propose that the multifunctional cytokine-like molecule HMGB1 released by activated, stressed, and damaged or necrotic cells can facilitate NMDAR-mediated cell responses, both in the central nervous system and in peripheral tissues, independently of other known cell surface receptors for HMGB1.

  3. CADM1 controls actin cytoskeleton assembly and regulates extracellular matrix adhesion in human mast cells.

    Directory of Open Access Journals (Sweden)

    Elena P Moiseeva

    Full Text Available CADM1 is a major receptor for the adhesion of mast cells (MCs to fibroblasts, human airway smooth muscle cells (HASMCs and neurons. It also regulates E-cadherin and alpha6beta4 integrin in other cell types. Here we investigated a role for CADM1 in MC adhesion to both cells and extracellular matrix (ECM. Downregulation of CADM1 in the human MC line HMC-1 resulted not only in reduced adhesion to HASMCs, but also reduced adhesion to their ECM. Time-course studies in the presence of EDTA to inhibit integrins demonstrated that CADM1 provided fast initial adhesion to HASMCs and assisted with slower adhesion to ECM. CADM1 downregulation, but not antibody-dependent CADM1 inhibition, reduced MC adhesion to ECM, suggesting indirect regulation of ECM adhesion. To investigate potential mechanisms, phosphotyrosine signalling and polymerisation of actin filaments, essential for integrin-mediated adhesion, were examined. Modulation of CADM1 expression positively correlated with surface KIT levels and polymerisation of cortical F-actin in HMC-1 cells. It also influenced phosphotyrosine signalling and KIT tyrosine autophosphorylation. CADM1 accounted for 46% of surface KIT levels and 31% of F-actin in HMC-1 cells. CADM1 downregulation resulted in elongation of cortical actin filaments in both HMC-1 cells and human lung MCs and increased cell rigidity of HMC-1 cells. Collectively these data suggest that CADM1 is a key adhesion receptor, which regulates MC net adhesion, both directly through CADM1-dependent adhesion, and indirectly through the regulation of other adhesion receptors. The latter is likely to occur via docking of KIT and polymerisation of cortical F-actin. Here we propose a stepwise model of adhesion with CADM1 as a driving force for net MC adhesion.

  4. Assessment of small RNA sorting into different extracellular fractions revealed by high-throughput sequencing of breast cell lines

    Science.gov (United States)

    Tosar, Juan Pablo; Gámbaro, Fabiana; Sanguinetti, Julia; Bonilla, Braulio; Witwer, Kenneth W.; Cayota, Alfonso

    2015-01-01

    Intercellular communication can be mediated by extracellular small regulatory RNAs (sRNAs). Circulating sRNAs are being intensively studied for their promising use as minimally invasive disease biomarkers. To date, most attention is centered on exosomes and microRNAs as the vectors and the secreted species, respectively. However, this field would benefit from an increased understanding of the plethora of sRNAs secreted by different cell types in different extracellular fractions. It is still not clear if specific sRNAs are selected for secretion, or if sRNA secretion is mostly passive. We sequenced the intracellular sRNA content (19–60 nt) of breast epithelial cell lines (MCF-7 and MCF-10A) and compared it with extracellular fractions enriched in microvesicles, exosomes and ribonucleoprotein complexes. Our results are consistent with a non-selective secretion model for most microRNAs, although a few showed secretion patterns consistent with preferential secretion. On the contrary, 5′ tRNA halves and 5′ RNA Y4-derived fragments of 31–33 were greatly and significantly enriched in the extracellular space (even in non-mammary cell lines), where tRNA halves were detected as part of ∼45 kDa ribonucleoprotein complexes. Overall, we show that different sRNA families have characteristic secretion patterns and open the question of the role of these sRNAs in the extracellular space. PMID:25940616

  5. Electrospun polyvinyl alcohol–collagen–hydroxyapatite nanofibers: a biomimetic extracellular matrix for osteoblastic cells

    International Nuclear Information System (INIS)

    Song Wei; Shi Tong; Ren Weiping; Markel, David C; Wang Sunxi; Mao Guangzhao

    2012-01-01

    The failure of prosthesis after total joint replacement is due to the lack of early implant osseointegration. In this study polyvinyl alcohol–collagen–hydroxyapatite (PVA-Col-HA) electrospun nanofibrous meshes were fabricated as a biomimetic bone-like extracellular matrix for the modification of orthopedic prosthetic surfaces. In order to reinforce the PVA nanofibers, HA nanorods and Type I collagen were incorporated into the nanofibers. We investigated the morphology, biodegradability, mechanical properties and biocompatibility of the prepared nanofibers. Our results showed these inorganic–organic blended nanofibers to be degradable in vitro. The encapsulated nano-HA and collagen interacted with the PVA content, reinforcing the hydrolytic resistance and mechanical properties of nanofibers that provided longer lasting stability. The encapsulated nano-HA and collagen also enhanced the adhesion and proliferation of murine bone cells (MC3T3) in vitro. We propose the PVA-Col-HA nanofibers might be promising modifying materials on implant surfaces for orthopedic applications. (paper)

  6. Mechanistic understanding of nanoparticles' interactions with extracellular matrix: the cell and immune system.

    Science.gov (United States)

    Engin, Ayse Basak; Nikitovic, Dragana; Neagu, Monica; Henrich-Noack, Petra; Docea, Anca Oana; Shtilman, Mikhail I; Golokhvast, Kirill; Tsatsakis, Aristidis M

    2017-06-24

    Extracellular matrix (ECM) is an extraordinarily complex and unique meshwork composed of structural proteins and glycosaminoglycans. The ECM provides essential physical scaffolding for the cellular constituents, as well as contributes to crucial biochemical signaling. Importantly, ECM is an indispensable part of all biological barriers and substantially modulates the interchange of the nanotechnology products through these barriers. The interactions of the ECM with nanoparticles (NPs) depend on the morphological characteristics of intercellular matrix and on the physical characteristics of the NPs and may be either deleterious or beneficial. Importantly, an altered expression of ECM molecules ultimately affects all biological processes including inflammation. This review critically discusses the specific behavior of NPs that are within the ECM domain, and passing through the biological barriers. Furthermore, regenerative and toxicological aspects of nanomaterials are debated in terms of the immune cells-NPs interactions.

  7. Microbially-reduced graphene scaffolds to facilitate extracellular electron transfer in microbial fuel cells.

    Science.gov (United States)

    Yuan, Yong; Zhou, Shungui; Zhao, Bo; Zhuang, Li; Wang, Yueqiang

    2012-07-01

    A one-pot method is exploited by adding graphene oxide (GO) and acetate into an microbial fuel cell (MFC) in which GO is microbially reduced, leading to in situ construction of a bacteria/graphene network in the anode. The obtained microbially reduced graphene (MRG) exhibits comparable conductivity and physical characteristics to the chemically reduced graphene. Electrochemical measurements reveal that the number of exoelectrogens involved in extracellular electron transfer (EET) to the solid electrode, increases due to the presence of graphene scaffolds, and the EET is facilitated in terms of electron transfer kinetics. As a result, the maximum power density of the MFC is enhanced by 32% (from 1440 to 1905 mW m(-2)) and the coulombic efficiency is improved by 80% (from 30 to 54%). The results demonstrate that the construction of the bacteria/graphene network is an effective alternative to improve the MFC performance. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. Patterned layers of adsorbed extracellular matrix proteins: influence on mammalian cell adhesion.

    Science.gov (United States)

    Dupont-Gillain, C C; Alaerts, J A; Dewez, J L; Rouxhet, P G

    2004-01-01

    Three patterned systems aiming at the control of mammalian cell behavior are presented. The determinant feature common to these systems is the spatial distribution of extracellular matrix (ECM) proteins (mainly collagen) on polymer substrates. This distribution differs from one system to another with respect to the scale at which it is affected, from the supracellular to the supramolecular scale, and with respect to the way it is produced. In the first system, the surface of polystyrene was oxidized selectively to form micrometer-scale patterns, using photolithography. Adsorption of ECM proteins in presence of a competitor was enhanced on the oxidized domains, allowing selective cell adhesion to be achieved. In the second system, electron beam lithography was used to engrave grooves (depth and width approximately 1 microm) on a poly(methyl methacrylate) (PMMA) substratum. No modification of the surface chemistry associated to the created topography could be detected. Cell orientation along the grooves was only observed when collagen was preadsorbed on the substratum. In the third system, collagen adsorbed on PMMA was dried in conditions ensuring the formation of a nanometer-scale pattern. Cell adhesion was enhanced on such patterned collagen layers compared to smooth collagen layers.

  9. Extracellular vesicles derived from mesenchymal stromal cells: a therapeutic option in respiratory diseases?

    Science.gov (United States)

    Abreu, Soraia C; Weiss, Daniel J; Rocco, Patricia R M

    2016-04-14

    Extracellular vesicles (EVs) are plasma membrane-bound fragments released from several cell types, including mesenchymal stromal cells (MSCs), constitutively or under stimulation. EVs derived from MSCs and other cell types transfer molecules (such as DNA, proteins/peptides, mRNA, microRNA, and lipids) and/or organelles with reparative and anti-inflammatory properties to recipient cells. The paracrine anti-inflammatory effects promoted by MSC-derived EVs have attracted significant interest in the regenerative medicine field, including for potential use in lung injuries. In the present review, we describe the characteristics, biological activities, and mechanisms of action of MSC-derived EVs. We also review the therapeutic potential of EVs as reported in relevant preclinical models of acute and chronic respiratory diseases, such as pneumonia, acute respiratory distress syndrome, asthma, and pulmonary arterial hypertension. Finally, we discuss possible approaches for potentiating the therapeutic effects of MSC-derived EVs so as to enable use of this therapy in clinical practice.

  10. Fluorescent Labeling of Collagen Production by Cells for Noninvasive Imaging of Extracellular Matrix Deposition.

    Science.gov (United States)

    Bardsley, Katie; Yang, Ying; El Haj, Alicia J

    2017-04-01

    Extracellular matrix (ECM) is an essential component of tissues and provides both integrity and biological cues for cells. Collagen is one of the major proteins found within the ECM and therefore is an essential component of all engineered tissues. Therefore, in this article, we present a method for the online real-time monitoring of collagen deposition in three-dimensional engineered constructs. This method revolves around modification of collagen through the addition of azide-L-proline to cell culture media. The incorporation of azide-L-proline into the neocollagen produced by cells can then be detected by reaction with 10 mM of a Click-IT Alexa Fluor 488 DIBO Alkyne. The reaction was shown as being specific to the collagen as little background staining was observed in cultures, which did not contain the modified proline, and the staining was also depleted after treatment with collagenase and colocalization of collagen type I staining by immunochemistry assay. Real-time online staining of collagen deposition was observed under different culture conditions without affecting proliferation. Collagen deposition was observed to be increased under mechanical stimulation; however, the localization varied across stimulation regimes. This is a new technique for real-time monitoring of cell-produced collagen and will be a valuable addition to the tissue engineering field.

  11. Differential and transferable modulatory effects of mesenchymal stromal cell-derived extracellular vesicles on T, B and NK cell functions.

    Science.gov (United States)

    Di Trapani, Mariano; Bassi, Giulio; Midolo, Martina; Gatti, Alessandro; Kamga, Paul Takam; Cassaro, Adriana; Carusone, Roberta; Adamo, Annalisa; Krampera, Mauro

    2016-04-13

    Mesenchymal stromal cells (MSCs) are multipotent cells, immunomodulatory stem cells that are currently used for regenerative medicine and treatment of a number of inflammatory diseases, thanks to their ability to significantly influence tissue microenvironments through the secretion of large variety of soluble factors. Recently, several groups have reported the presence of extracellular vesicles (EVs) within MSC secretoma, showing their beneficial effect in different animal models of disease. Here, we used a standardized methodological approach to dissect the immunomodulatory effects exerted by MSC-derived EVs on unfractionated peripheral blood mononuclear cells and purified T, B and NK cells. We describe here for the first time: i. direct correlation between the degree of EV-mediated immunosuppression and EV uptake by immune effector cells, a phenomenon further amplified following MSC priming with inflammatory cytokines; ii. induction in resting MSCs of immunosuppressive properties towards T cell proliferation through EVs obtained from primed MSCs, without any direct inhibitory effect towards T cell division. Our conclusion is that the use of reproducible and validated assays is not only useful to characterize the mechanisms of action of MSC-derived EVs, but is also capable of justifying EV potential use as alternative cell-free therapy for the treatment of human inflammatory diseases.

  12. Novel use for polyvinylpyrrolidone as a macromolecular crowder for enhanced extracellular matrix deposition and cell proliferation.

    Science.gov (United States)

    Rashid, Rafi; Lim, Natalie Sheng Jie; Chee, Stella Min Ling; Png, Si Ning; Wohland, Thorsten; Raghunath, Michael

    2014-12-01

    Macromolecular crowding (MMC) is a biophysical effect that governs biochemical processes inside and outside of cells. Since standard cell culture media lack this effect, the physiological performance of differentiated and progenitor cells, including extracellular matrix (ECM) deposition, is impaired in vitro. To bring back physiological crowdedness to in vitro systems, we have previously introduced carbohydrate-based macromolecules to culture media and have achieved marked improvements with mixed MMC in terms of ECM deposition and differentiation of mesenchymal stem cells (MSCs). We show here that although this system is successful, it is limited, due to viscosity, to only 33% of the fractional volume occupancy (FVO) of full serum, which we calculated to have an FVO of approximately 54% v/v. We show here that full-serum FVO can be achieved using polyvinylpyrrolidone (PVP) 360 kDa. Under these conditions, ECM deposition in human fibroblasts and MSCs is on par, if not stronger than, with original MMC protocols using carbohydrates, but with a viscosity that is not significantly changed. In addition, we have found that the proliferation rate for bone marrow-derived MSCs and fibroblasts increases slightly in the presence of PVP360, similar to that observed with carbohydrate-based crowders. A palette of MMC compounds is now emerging that enables us to tune the crowdedness of culture media seamlessly from interstitial fluid (9% FVO), in which the majority of tissue cells might be based, to serum environments mimicking intravascular conditions. Despite identical FVO's, individual crowder size effects play a role and different cell types appear to have preferences in terms of FVO and the crowder that this is achieved with. However, in the quest of crowders that we have predicted to have a smoother regulatory approval path, PVP is a highly interesting compound, as it has been widely used in the medical and food industries and shows a novel promising use in cell culture and

  13. An extracellular DNA mediated bystander effect produced from low dose irradiated endothelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Ermakov, Aleksei V., E-mail: avePlato@mail.ru [Research Centre for Medical Genetics, Russian Academy of Medical Sciences, Moscow (Russian Federation); Konkova, Marina S.; Kostyuk, Svetlana V.; Smirnova, Tatiana D.; Malinovskaya, Elena M.; Efremova, Liudmila V.; Veiko, Natalya N. [Research Centre for Medical Genetics, Russian Academy of Medical Sciences, Moscow (Russian Federation)

    2011-07-01

    The human umbilical vein endothelial cells culture was exposed to X-ray radiation in a low dose of 10 cGy. The fragments of extracellular genomic DNA (ecDNA{sup R}) were isolated from the culture medium after the short-term incubation. A culture medium of unirradiated endothelial cells was then supplemented with ecDNA{sup R}, followed by analysing the cells along the series of parameters (bystander effect). The exposed cells and bystander endotheliocytes showed similar response to low doses: approximation of the 1q12 loci of chromosome 1 and their transposition into the cellular nucleus, change in shape of the endotheliocytic nucleus, activation of the nucleolus organizing regions (NORs), actin polymerization, and an elevated level of DNA double-stranded breaks. Following blockade of TLR9 receptors with oligonucleotide-inhibitor or chloroquine in the bystander cells these effects - except of activation of NORs - on exposure to ecDNA{sup R} disappeared, with no bystander response thus observed. The presence of the radiation-induced apoptosis in the bystander effect being studied suggests a possibility for radiation-modified ecDNA fragments (i.e., stress signaling factors) to be released into the culture medium, whereas inhibition of TLR9 suggests the binding these ligands to the recipient cells. A similar DNA-signaling pathway in the bystander effect we previously described for human lymphocytes. Integrity of data makes it possible to suppose that a similar signaling mechanism which we demonstrated for lymphocytes (humoral system) might also be mediated in a monolayer culture of cells (cellular tissue) after the development of the bystander effect in them and transfer of stress signaling factors (ecDNA{sup R}) through the culture medium.

  14. An extracellular DNA mediated bystander effect produced from low dose irradiated endothelial cells

    International Nuclear Information System (INIS)

    Ermakov, Aleksei V.; Konkova, Marina S.; Kostyuk, Svetlana V.; Smirnova, Tatiana D.; Malinovskaya, Elena M.; Efremova, Liudmila V.; Veiko, Natalya N.

    2011-01-01

    The human umbilical vein endothelial cells culture was exposed to X-ray radiation in a low dose of 10 cGy. The fragments of extracellular genomic DNA (ecDNA R ) were isolated from the culture medium after the short-term incubation. A culture medium of unirradiated endothelial cells was then supplemented with ecDNA R , followed by analysing the cells along the series of parameters (bystander effect). The exposed cells and bystander endotheliocytes showed similar response to low doses: approximation of the 1q12 loci of chromosome 1 and their transposition into the cellular nucleus, change in shape of the endotheliocytic nucleus, activation of the nucleolus organizing regions (NORs), actin polymerization, and an elevated level of DNA double-stranded breaks. Following blockade of TLR9 receptors with oligonucleotide-inhibitor or chloroquine in the bystander cells these effects - except of activation of NORs - on exposure to ecDNA R disappeared, with no bystander response thus observed. The presence of the radiation-induced apoptosis in the bystander effect being studied suggests a possibility for radiation-modified ecDNA fragments (i.e., stress signaling factors) to be released into the culture medium, whereas inhibition of TLR9 suggests the binding these ligands to the recipient cells. A similar DNA-signaling pathway in the bystander effect we previously described for human lymphocytes. Integrity of data makes it possible to suppose that a similar signaling mechanism which we demonstrated for lymphocytes (humoral system) might also be mediated in a monolayer culture of cells (cellular tissue) after the development of the bystander effect in them and transfer of stress signaling factors (ecDNA R ) through the culture medium.

  15. A genetically encoded ratiometric sensor to measure extracellular pH in microdomains bounded by basolateral membranes of epithelial cells.

    Science.gov (United States)

    Urra, Javier; Sandoval, Moisés; Cornejo, Isabel; Barros, L Felipe; Sepúlveda, Francisco V; Cid, L Pablo

    2008-10-01

    Extracellular pH, especially in relatively inaccessible microdomains between cells, affects transport membrane protein activity and might have an intercellular signaling role. We have developed a genetically encoded extracellular pH sensor capable of detecting pH changes in basolateral spaces of epithelial cells. It consists of a chimerical membrane protein displaying concatenated enhanced variants of cyan fluorescence protein (ECFP) and yellow fluorescence protein (EYFP) at the external aspect of the cell surface. The construct, termed pHCECSensor01, was targeted to basolateral membranes of Madin-Darby canine kidney (MDCK) cells by means of a sequence derived from the aquaporin AQP4. The fusion of pH-sensitive EYFP with pH-insensitive ECFP allows ratiometric pH measurements. The titration curve of pHCECSensor01 in vivo had a pK (a) value of 6.5 +/- 0.04. Only minor effects of extracellular chloride on pHCECSensor01 were observed around the physiological concentrations of this anion. In MDCK cells, the sensor was able to detect changes in pH secondary to H(+) efflux into the basolateral spaces elicited by an ammonium prepulse or lactate load. This genetically encoded sensor has the potential to serve as a noninvasive tool for monitoring changes in extracellular pH microdomains in epithelial and other tissues in vivo.

  16. Extracellular visfatin activates gluconeogenesis in HepG2 cells through the classical PKA/CREB-dependent pathway.

    Science.gov (United States)

    Choi, Y J; Choi, S-E; Ha, E S; Kang, Y; Han, S J; Kim, D J; Lee, K W; Kim, H J

    2014-04-01

    Adipokines reportedly affect hepatic gluconeogenesis, and the adipokine visfatin is known to be related to insulin resistance and type 2 diabetes. However, whether visfatin contributes to hepatic gluconeogenesis remains unclear. Visfatin, also known as nicotinamide phosphoribosyltransferase (NAMPT), modulates sirtuin1 (SIRT1) through the regulation of nicotinamide adenine dinucleotide (NAD). Therefore, we investigated the effect of extracellular visfatin on glucose production in HepG2 cells, and evaluated whether extracellular visfatin affects hepatic gluconeogenesis via an NAD+-SIRT1-dependent pathway. Treatment with visfatin significantly increased glucose production and the mRNA expression and protein levels of phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase) in HepG2 cells in a time- and concentration-dependent manner. Knockdown of SIRT1 had no remarkable effect on the induction of gluconeogenesis by visfatin. Subsequently, we evaluated if extracellular visfatin stimulates the production of gluconeogenic enzymes through the classical protein kinase A (PKA)/cyclic AMP-responsive element (CRE)-binding protein (CREB)-dependent process. The phosphorylation of CREB and PKA increased significantly in HepG2 cells treated with visfatin. Additionally, knockdown of CREB and PKA inhibited visfatin-induced gluconeogenesis in HepG2 cells. In summary, extracellular visfatin modulates glucose production in HepG2 cells through the PKA/CREB pathway, rather than via SIRT1 signaling. © Georg Thieme Verlag KG Stuttgart · New York.

  17. Effects of extracellular matrix proteins on the growth of haematopoietic progenitor cells

    International Nuclear Information System (INIS)

    Celebi, Betuel; Pineault, Nicolas; Mantovani, Diego

    2011-01-01

    Umbilical cord blood (UCB) transplantation and haematological recovery are currently limited by the amount of haematopoietic progenitor cells (HPCs) present in each unit. HPCs and haematopoietic stem cells (HSCs) normally interact with cells and extracellular matrix (ECM) proteins present within the endosteal and vascular niches. Hence, we investigated whether coating of culture surfaces with ECM proteins normally present in the marrow microenvironment could benefit the ex vivo expansion of HPCs. Towards this, collagen types I and IV (COL I and IV), laminin (LN) and fibronectin (FN) were tested individually or as component of two ECM-mix complexes. Individually, ECM proteins had both common and unique properties on the growth and differentiation of UCB CD34+ cells; some ECM proteins favoured the differentiation of some lineages over that of others (e.g. FN for erythroids), some the expansion of HPCs (e.g. LN and megakaryocyte (MK) progenitor) while others had less effects. Next, two ECM-mix complexes were tested; the first one contained all four ECM proteins (4ECMp), while the second 'basement membrane-like structure' was without COL I (3ECMp). Removal of COL I led to strong reductions in cell growth and HPCs expansion. Interestingly, the 4ECMp-mix complex reproducibly increased CD34+ (1.3-fold) and CD41+ (1.2-fold) cell expansions at day 6 (P < 0.05) versus control, and induced greater myeloid progenitor expansion (P < 0.05) than 3ECMp. In conclusion, these results suggest that optimization of BM ECM protein complexes could provide a better environment for the ex vivo expansion of haematopoietic progenitors than individual ECM protein.

  18. Effects of extracellular matrix proteins on the growth of haematopoietic progenitor cells

    Energy Technology Data Exchange (ETDEWEB)

    Celebi, Betuel; Pineault, Nicolas [Hema-Quebec, Research and Development Department, Quebec City, G1V 5C3, PQ (Canada); Mantovani, Diego, E-mail: nicolas.pineault@hema-quebec.qc.ca [Laboratory for Biomaterials and Bioengineering, Department of Materials Engineering and University Hospital Research Center, Laval University, Quebec City, G1V 0A6, PQ (Canada)

    2011-10-15

    Umbilical cord blood (UCB) transplantation and haematological recovery are currently limited by the amount of haematopoietic progenitor cells (HPCs) present in each unit. HPCs and haematopoietic stem cells (HSCs) normally interact with cells and extracellular matrix (ECM) proteins present within the endosteal and vascular niches. Hence, we investigated whether coating of culture surfaces with ECM proteins normally present in the marrow microenvironment could benefit the ex vivo expansion of HPCs. Towards this, collagen types I and IV (COL I and IV), laminin (LN) and fibronectin (FN) were tested individually or as component of two ECM-mix complexes. Individually, ECM proteins had both common and unique properties on the growth and differentiation of UCB CD34+ cells; some ECM proteins favoured the differentiation of some lineages over that of others (e.g. FN for erythroids), some the expansion of HPCs (e.g. LN and megakaryocyte (MK) progenitor) while others had less effects. Next, two ECM-mix complexes were tested; the first one contained all four ECM proteins (4ECMp), while the second 'basement membrane-like structure' was without COL I (3ECMp). Removal of COL I led to strong reductions in cell growth and HPCs expansion. Interestingly, the 4ECMp-mix complex reproducibly increased CD34+ (1.3-fold) and CD41+ (1.2-fold) cell expansions at day 6 (P < 0.05) versus control, and induced greater myeloid progenitor expansion (P < 0.05) than 3ECMp. In conclusion, these results suggest that optimization of BM ECM protein complexes could provide a better environment for the ex vivo expansion of haematopoietic progenitors than individual ECM protein.

  19. Mesenchymal stem cells from different murine tissues have differential capacity to metabolize extracellular nucleotides.

    Science.gov (United States)

    Iser, Isabele C; Bracco, Paula A; Gonçalves, Carlos E I; Zanin, Rafael F; Nardi, Nance B; Lenz, Guido; Battastini, Ana Maria O; Wink, Márcia R

    2014-10-01

    Mesenchymal stem cells (MSCs) have shown a great potential for cell-based therapy and many different therapeutic purposes. Despite the recent advances in the knowledge of MSCs biology, their biochemical and molecular properties are still poorly defined. Ecto-nucleoside triphosphate diphosphohydrolases (E-NTPDases) and ecto-5'-nucleotidase (eNT/CD73) are widely expressed enzymes that hydrolyze extracellular nucleotides, generating an important cellular signaling cascade. Currently, studies have evidenced the relationship between the purinergic system and the development, maintenance, and differentiation of stem cells. The objective of this study is to identify the NTPDases and eNT/CD73 and compare the levels of nucleotide hydrolysis on MSCs isolated from different murine tissues (bone marrow, lung, vena cava, kidney, pancreas, spleen, skin, and adipose tissue). MSCs from all tissues investigated expressed the ectoenzymes at different levels. In MSCs from pancreas and adipose tissue, the hydrolysis of triphosphonucleosides was significantly higher when compared to the other cells. The diphosphonucleosides were hydrolyzed at a higher rate by MSC from pancreas when compared to MSC from other tissues. The differential nucleotide hydrolysis activity and enzyme expression in these cells suggests that MSCs play different roles in regulating the purinergic system in these tissues. Overall MSCs are an attractive adult-derived cell population for therapies, however, the fact that ecto-nucleotide metabolism can affect the microenvironment, modulating important events, such as immune response, makes the assessment of this metabolism an important part of the characterization of MSCs to be applied therapeutically. © 2014 Wiley Periodicals, Inc.

  20. Illustration of extensive extracellular matrix at the epithelial-mesenchymal interface within the renal stem/progenitor cell niche

    Directory of Open Access Journals (Sweden)

    Minuth Will W

    2012-09-01

    Full Text Available Abstract Background Stem/progenitor cells are promising candidates to treat diseased renal parenchyma. However, implanted stem/progenitor cells are exposed to a harmful atmosphere of degenerating parenchyma. To minimize hampering effects after an implantation investigations are in progress to administer these cells within an artificial polyester interstitum supporting survival. Learning from nature the renal stem/progenitor cell niche appears as a valuable model. At this site epithelial stem/progenitor cells within the collecting duct ampulla face mesenchymal stem/progenitor cells. Both cell types do not have close contact but are separated by a wide interstitium. Methods To analyze extracellular matrix in this particular interstitium, special contrasting for transmission electron microscopy was performed. Kidneys of neonatal rabbits were fixed in solutions containing glutaraldehyde (GA or in combination with cupromeronic blue, ruthenium red and tannic acid. Results GA revealed a basal lamina at the ampulla and a bright but inconspicuously looking interstitial space. In contrast, GA containing cupromeronic blue exhibits numerous proteoglycan braces lining from the ampulla towards the interstitial space. GA containing ruthenium red or tannic acid demonstrates clouds of extracellular matrix protruding from the basal lamina of the ampulla to the surface of mesenchymal stem/progenitor cells. Conclusions The actual data show that the interstitium between epithelial and mesenchymal stem/progenitor cells contains much more and up to date unknown extracellular matrix than earlier observed by classical GA fixation.

  1. Extracellular Vesicles: How the External and Internal Environment Can Shape Cell-To-Cell Communication.

    Science.gov (United States)

    Neven, Kristof Y; Nawrot, Tim S; Bollati, Valentina

    2017-03-01

    To summarize the scientific evidence regarding the effects of environmental exposures on extracellular vesicle (EV) release and their contents. As environmental exposures might influence the aging phenotype in a very strict way, we will also report the role of EVs in the biological aging process. EV research is a new and quickly developing field. With many investigations conducted so far, only a limited number of studies have explored the potential role EVs play in the response and adaptation to environmental stimuli. The investigations available to date have identified several exposures or lifestyle factors able to modify EV trafficking including air pollutants, cigarette smoke, alcohol, obesity, nutrition, physical exercise, and oxidative stress. EVs are a very promising tool, as biological fluids are easily obtainable biological media that, if successful in identifying early alterations induced by the environment and predictive of disease, would be amenable to use for potential future preventive and diagnostic applications.

  2. Extracellular vesicle in vivo biodistribution is determined by cell source, route of administration and targeting

    Directory of Open Access Journals (Sweden)

    Oscar P. B. Wiklander

    2015-04-01

    Full Text Available Extracellular vesicles (EVs have emerged as important mediators of intercellular communication in a diverse range of biological processes. For future therapeutic applications and for EV biology research in general, understanding the in vivo fate of EVs is of utmost importance. Here we studied biodistribution of EVs in mice after systemic delivery. EVs were isolated from 3 different mouse cell sources, including dendritic cells (DCs derived from bone marrow, and labelled with a near-infrared lipophilic dye. Xenotransplantation of EVs was further carried out for cross-species comparison. The reliability of the labelling technique was confirmed by sucrose gradient fractionation, organ perfusion and further supported by immunohistochemical staining using CD63-EGFP probed vesicles. While vesicles accumulated mainly in liver, spleen, gastrointestinal tract and lungs, differences related to EV cell origin were detected. EVs accumulated in the tumour tissue of tumour-bearing mice and, after introduction of the rabies virus glycoprotein-targeting moiety, they were found more readily in acetylcholine-receptor-rich organs. In addition, the route of administration and the dose of injected EVs influenced the biodistribution pattern. This is the first extensive biodistribution investigation of EVs comparing the impact of several different variables, the results of which have implications for the design and feasibility of therapeutic studies using EVs.

  3. Effects of extracellular calcium on viability and osteogenic differentiation of bone marrow stromal cells in vitro.

    Science.gov (United States)

    Cheng, Shaowen; Wang, Wei; Lin, Zhongqin; Zhou, Ping; Zhang, Xiaolei; Zhang, Wei; Chen, Qingyu; Kou, Dongquan; Ying, Xiaozhou; Shen, Yue; Cheng, Xiaojie; Yu, Ziming; Peng, Lei; Lu, Chuanzhu

    2013-09-01

    Bone marrow stromal cells (BMSCs) have been extensively used for tissue engineering. However, the effect of Ca(2+) on the viability and osteogenic differentiation of BMSCs has yet to be evaluated. To determine the dose-dependent effect of Ca(2+) on viability and osteogenesis of BMSCs in vitro, BMSCs were cultured in calcium-free DMEM medium supplemented with various concentrations of Ca(2+) (0, 1, 2, 3, 4, and 5 mM) from calcium citrate. Cell viability was analyzed by MTT assay and osteogenic differentiation was evaluated by alkaline phosphatase (ALP) assay, Von Kossa staining, and real-time PCR. Ca(2+) stimulated BMSCs viability in a dose-dependent manner. At slightly higher concentrations (4 and 5 mM) in the culture, Ca(2+) significantly inhibited the activity of ALP on days 7 and 14 (P < 0.01 or P < 0.05), significantly suppressed collagen synthesis (P < 0.01 or P < 0.05), and significantly elevated calcium deposition (P < 0.01) and mRNA levels of osteocalcin (P < 0.01 or P < 0.05) and osteopontin (P < 0.01 or P < 0.05). Therefore, elevated concentrations of extracellular calcium may promote cell viability and late-stage osteogenic differentiation, but may suppress early-stage osteogenic differentiation in BMSCs.

  4. Elastase effect on the extracellular matrix of rat aortic smooth muscle cells in culture

    International Nuclear Information System (INIS)

    Kispert, J.; Mogayzel, P.J. Jr.; Pratt, C.A.; Toselli, P.; Wolfe, B.L.; Faris, B.; Franzblau, C.

    1986-01-01

    The effect of porcine pancreatic elastase on the extracellular matrix (ECM) of neonatal rat aortic smooth muscle cell cultures was monitored both chemically and ultrastructurally. Initially, the elastin appeared as non-coalesced material closely associated with filaments, presumably microfibrils. The insoluble elastin accumulated in the ECM of cells in culture for 6 weeks accounted for 40-45% of the total protein. After exposure to elastase for 30-60 minutes, the elastin content was reduced to 14-20%. The reduction in the total protein content of the cultures after elastase treatment was due primarily to the loss of elastin. Although the amino acid compositions of the elastin isolated from cultures both before and after elastase treatment were similar, there were striking ultrastructural differences in the amorphous elastin. The elastin assumed a mottled appearance after elastase exposure, similar to that seen in in vivo emphysema models. Pulse experiments with 3 H-valine demonstrated an increase in protein synthesis by the cells 20 hours after elastase exposure, suggesting the potential for elastin repair. The use of this culture system will aid in clarifying the role of elastolysis in pulmonary and vascular injuries

  5. Extracellular Matrix Proteins Expression Profiling in Chemoresistant Variants of the A2780 Ovarian Cancer Cell Line

    Directory of Open Access Journals (Sweden)

    Radosław Januchowski

    2014-01-01

    Full Text Available Ovarian cancer is the leading cause of death among gynaecological malignancies. Extracellular matrix (ECM can affect drug resistance by preventing the penetration of the drug into cancer cells and increased resistance to apoptosis. This study demonstrates alterations in the expression levels of ECM components and related genes in cisplatin-, doxorubicin-, topotecan-, and paclitaxel-resistant variants of the A2780 ovarian cancer cell line. Affymetrix Gene Chip Human Genome Array Strips were used for hybridisations. The genes that had altered expression levels in drug-resistant sublines were selected and filtered by scatter plots. The genes that were up- or downregulated more than fivefold were selected and listed. Among the investigated genes, 28 genes were upregulated, 10 genes were downregulated, and two genes were down- or upregulated depending on the cell line. Between upregulated genes 12 were upregulated very significantly—over 20-fold. These genes included COL1A2, COL12A1, COL21A1, LOX, TGFBI, LAMB1, EFEMP1, GPC3, SDC2, MGP, MMP3, and TIMP3. Four genes were very significantly downregulated: COL11A1, LAMA2, GPC6, and LUM. The expression profiles of investigated genes provide a preliminary insight into the relationship between drug resistance and the expression of ECM components. Identifying correlations between investigated genes and drug resistance will require further analysis.

  6. Staphylococcus aureus extracellular adherence protein triggers TNFα release, promoting attachment to endothelial cells via protein A.

    Directory of Open Access Journals (Sweden)

    Andrew M Edwards

    Full Text Available Staphylococcus aureus is a leading cause of bacteraemia, which frequently results in complications such as infective endocarditis, osteomyelitis and exit from the bloodstream to cause metastatic abscesses. Interaction with endothelial cells is critical to these complications and several bacterial proteins have been shown to be involved. The S. aureus extracellular adhesion protein (Eap has many functions, it binds several host glyco-proteins and has both pro- and anti-inflammatory activity. Unfortunately its role in vivo has not been robustly tested to date, due to difficulties in complementing its activity in mutant strains. We previously found Eap to have pro-inflammatory activity, and here show that purified native Eap triggered TNFα release in whole human blood in a dose-dependent manner. This level of TNFα increased adhesion of S. aureus to endothelial cells 4-fold via a mechanism involving protein A on the bacterial surface and gC1qR/p33 on the endothelial cell surface. The contribution this and other Eap activities play in disease severity during bacteraemia was tested by constructing an isogenic set of strains in which the eap gene was inactivated and complemented by inserting an intact copy elsewhere on the bacterial chromosome. Using a murine bacteraemia model we found that Eap expressing strains cause a more severe infection, demonstrating its role in invasive disease.

  7. Group A Streptococcus Prevents Mast Cell Degranulation to Promote Extracellular Trap Formation

    Directory of Open Access Journals (Sweden)

    Mary Clark

    2018-02-01

    Full Text Available The resurgence of Group A Streptococcus (GAS infections in the past two decades has been a rising major public health concern. Due to a large number of GAS infections occurring in the skin, mast cells (MCs, innate immune cells known to localize to the dermis, could play an important role in controlling infection. MCs can exert their antimicrobial activities either early during infection, by degranulation and release of antimicrobial proteases and the cathelicidin-derived antimicrobial peptide LL-37, or by forming antibacterial MC extracellular traps (MCETs in later stages of infection. We demonstrate that MCs do not directly degranulate in response to GAS, reducing their ability to control bacterial growth in early stages of infection. However, MC granule components are highly cytotoxic to GAS due to the pore-forming activity of LL-37, while MC granule proteases do not significantly affect GAS viability. We therefore confirmed the importance of MCETs by demonstrating their capacity to reduce GAS survival. The data therefore suggests that LL-37 from MC granules become embedded in MCETs, and are the primary effector molecule by which MCs control GAS infection. Our work underscores the importance of a non-traditional immune effector cell, utilizing a non-conventional mechanism, in the defense against an important human pathogen.

  8. Tissue-specific extracellular matrix coatings for the promotion of cell proliferation and maintenance of cell phenotype.

    Science.gov (United States)

    Zhang, Yuanyuan; He, Yujiang; Bharadwaj, Shantaram; Hammam, Nevin; Carnagey, Kristen; Myers, Regina; Atala, Anthony; Van Dyke, Mark

    2009-08-01

    Recent studies have shown that extracellular matrix (ECM) substitutes can have a dramatic impact on cell growth, differentiation and function. However, these ECMs are often applied generically and have yet to be developed for specific cell types. In this study, we developed tissue-specific ECM-based coating substrates for skin, skeletal muscle and liver cell cultures. Cellular components were removed from adult skin, skeletal muscle, and liver tissues, and the resulting acellular matrices were homogenized and dissolved. The ECM solutions were used to coat culture dishes. Tissue matched and non-tissue matched cell types were grown on these coatings to assess adhesion, proliferation, maintenance of phenotype and cell function at several time points. Each cell type showed better proliferation and differentiation in cultures containing ECM from their tissue of origin. Although subtle compositional differences in the three ECM types were not investigated in this study, these results suggest that tissue-specific ECMs provide a culture microenvironment that is similar to the in vivo environment when used as coating substrates, and this new culture technique has the potential for use in drug development and the development of cell-based therapies.

  9. Extracellular Membrane Vesicles as Vehicles for Brain Cell-to-Cell Interactions in Physiological as well as Pathological Conditions

    Directory of Open Access Journals (Sweden)

    Gabriella Schiera

    2015-01-01

    Full Text Available Extracellular vesicles are involved in a great variety of physiological events occurring in the nervous system, such as cross talk among neurons and glial cells in synapse development and function, integrated neuronal plasticity, neuronal-glial metabolic exchanges, and synthesis and dynamic renewal of myelin. Many of these EV-mediated processes depend on the exchange of proteins, mRNAs, and noncoding RNAs, including miRNAs, which occurs among glial and neuronal cells. In addition, production and exchange of EVs can be modified under pathological conditions, such as brain cancer and neurodegeneration. Like other cancer cells, brain tumours can use EVs to secrete factors, which allow escaping from immune surveillance, and to transfer molecules into the surrounding cells, thus transforming their phenotype. Moreover, EVs can function as a way to discard material dangerous to cancer cells, such as differentiation-inducing proteins, and even drugs. Intriguingly, EVs seem to be also involved in spreading through the brain of aggregated proteins, such as prions and aggregated tau protein. Finally, EVs can carry useful biomarkers for the early diagnosis of diseases. Herein we summarize possible roles of EVs in brain physiological functions and discuss their involvement in the horizontal spreading, from cell to cell, of both cancer and neurodegenerative pathologies.

  10. Extracellular pH Modulates Neuroendocrine Prostate Cancer Cell Metabolism and Susceptibility to the Mitochondrial Inhibitor Niclosamide

    Science.gov (United States)

    Ippolito, Joseph E.; Brandenburg, Matthew W.; Ge, Xia; Crowley, Jan R.; Kirmess, Kristopher M.; Som, Avik; D’Avignon, D. Andre; Arbeit, Jeffrey M.; Achilefu, Samuel; Yarasheski, Kevin E.; Milbrandt, Jeffrey

    2016-01-01

    Neuroendocrine prostate cancer is a lethal variant of prostate cancer that is associated with castrate-resistant growth, metastasis, and mortality. The tumor environment of neuroendocrine prostate cancer is heterogeneous and characterized by hypoxia, necrosis, and numerous mitoses. Although acidic extracellular pH has been implicated in aggressive cancer features including metastasis and therapeutic resistance, its role in neuroendocrine prostate cancer physiology and metabolism has not yet been explored. We used the well-characterized PNEC cell line as a model to establish the effects of extracellular pH (pH 6.5, 7.4, and 8.5) on neuroendocrine prostate cancer cell metabolism. We discovered that alkalinization of extracellular pH converted cellular metabolism to a nutrient consumption-dependent state that was susceptible to glucose deprivation, glutamine deprivation, and 2-deoxyglucose (2-DG) mediated inhibition of glycolysis. Conversely, acidic pH shifted cellular metabolism toward an oxidative phosphorylation (OXPHOS)-dependent state that was susceptible to OXPHOS inhibition. Based upon this mechanistic knowledge of pH-dependent metabolism, we identified that the FDA-approved anti-helminthic niclosamide depolarized mitochondrial potential and depleted ATP levels in PNEC cells whose effects were enhanced in acidic pH. To further establish relevance of these findings, we tested the effects of extracellular pH on susceptibility to nutrient deprivation and OXPHOS inhibition in a cohort of castrate-resistant prostate cancer cell lines C4-2B, PC-3, and PC-3M. We discovered similar pH-dependent toxicity profiles among all cell lines with these treatments. These findings underscore a potential importance to acidic extracellular pH in the modulation of cell metabolism in tumors and development of an emerging paradigm that exploits the synergy of environment and therapeutic efficacy in cancer. PMID:27438712

  11. The influence of an in vitro generated bone-like extracellular matrix on osteoblastic gene expression of marrow stromal cells.

    NARCIS (Netherlands)

    Pham, Q.P.; Kasper, F.K.; Baggett, L.S.; Raphael, R.M.; Jansen, J.A.; Mikos, A.G.

    2008-01-01

    The function and development of cells rely heavily on the signaling interactions with the surrounding extracellular matrix (ECM). Therefore, a tissue engineering scaffold should mimic native ECM to recreate the in vivo environment. Previously, we have shown that an in vitro generated ECM secreted by

  12. Update on controls for isolation and quantification methodology of extracellular vesicles derived from adipose tissue mesenchymal stem cells

    NARCIS (Netherlands)

    M. Franquesa (Marcella); M.J. Hoogduijn (Martin); E. Ripoll (Elia); F. Luk (Franka); M. Salih (Mahdi); M.G.H. Betjes (Michiel); J. Torras; C.C. Baan (Carla); J. Grinyo (Josep); A. Merino (Ana)

    2014-01-01

    textabstractThe research field on extracellular vesicles (EV) has rapidly expanded in recent years due to the therapeutic potential of EV. Adipose tissue human mesenchymal stem cells (ASC) may be a suitable source for therapeutic EV. A major limitation in the field is the lack of standardization of

  13. The cytotoxicity of 3-bromopyruvate in breast cancer cells depends on extracellular pH.

    Science.gov (United States)

    Azevedo-Silva, João; Queirós, Odília; Ribeiro, Ana; Baltazar, Fátima; Young, Ko H; Pedersen, Peter L; Preto, Ana; Casal, Margarida

    2015-04-15

    Although the anti-cancer properties of 3BP (3-bromopyruvate) have been described previously, its selectivity for cancer cells still needs to be explained [Ko et al. (2001) Cancer Lett. 173, 83-91]. In the present study, we characterized the kinetic parameters of radiolabelled [14C] 3BP uptake in three breast cancer cell lines that display different levels of resistance to 3BP: ZR-75-1 < MCF-7 < SK-BR-3. At pH 6.0, the affinity of cancer cells for 3BP transport correlates with their sensitivity, a pattern that does not occur at pH 7.4. In the three cell lines, the uptake of 3BP is dependent on the protonmotive force and is decreased by MCTs (monocarboxylate transporters) inhibitors. In the SK-BR-3 cell line, a sodium-dependent transport also occurs. Butyrate promotes the localization of MCT-1 at the plasma membrane and increases the level of MCT-4 expression, leading to a higher sensitivity for 3BP. In the present study, we demonstrate that this phenotype is accompanied by an increase in affinity for 3BP uptake. Our results confirm the role of MCTs, especially MCT-1, in 3BP uptake and the importance of cluster of differentiation (CD) 147 glycosylation in this process. We find that the affinity for 3BP transport is higher when the extracellular milieu is acidic. This is a typical phenotype of tumour microenvironment and explains the lack of secondary effects of 3BP already described in in vivo studies [Ko et al. (2004) Biochem. Biophys. Res. Commun. 324, 269-275].

  14. Extracellular vesicles have variable dose-dependent effects on cultured draining cells in the eye.

    Science.gov (United States)

    Tabak, Saray; Schreiber-Avissar, Sofia; Beit-Yannai, Elie

    2018-03-01

    The role of extracellular vesicles (EVs) as signal mediators has been described in many biological fields. How many EVs are needed to deliver the desired physiological signal is yet unclear. Using a normal trabecular meshwork (NTM) cell culture exposed to non-pigmented ciliary epithelium (NPCE)-derived EVs, a relevant model for studying the human ocular drainage system, we addressed the EVs dose-response effects on the Wnt signaling. The objective of the study was to investigate the dosing effects of NPCE-derived EVs on TM Wnt signaling. EVs were isolated by PEG 8000 method from NPCE and RPE cells (used as controls) conditioned media. Concentrations were determined by Tunable Resistive Pulse Sensing method. Various exosomes concentration were incubated with TM cells, for the determination of mRNA (β-Catenin, Axin2 and LEF1) and protein (β-Catenin, GSK-3β) expression using real-time quantitative PCR and Western blot, respectively. Exposure of NTM cells for 8 hrs to low EVs concentrations was associated with a significant decreased expression of β-Catenin, GSK-3β, as opposed to exposure to high exosomal concentrations. Pro-MMP9 and MMP9 activities were significantly enhanced in NTM cells treated with high EV concentrations of (X10) as compared to low EV concentrations of either NPCE- or RPE-derived EVs and to untreated control. Our data support the concept that EVs biological effects are concentration-dependent at their target site. Specifically in the present study, we described a general dose-response at the gene and MMPs activity and a different dose-response regarding key canonical Wnt proteins expression. © 2018 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  15. Smooth muscle cell rigidity and extracellular matrix organization influence endothelial cell spreading and adhesion formation in coculture.

    Science.gov (United States)

    Wallace, Charles S; Strike, Sophie A; Truskey, George A

    2007-09-01

    Efforts to develop functional tissue-engineered blood vessels have focused on improving the strength and mechanical properties of the vessel wall, while the functional status of the endothelium within these vessels has received less attention. Endothelial cell (EC) function is influenced by interactions between its basal surface and the underlying extracellular matrix. In this study, we utilized a coculture model of a tissue-engineered blood vessel to evaluate EC attachment, spreading, and adhesion formation to the extracellular matrix on the surface of quiescent smooth muscle cells (SMCs). ECs attached to and spread on SMCs primarily through the alpha(5)beta(1)-integrin complex, whereas ECs used either alpha(5)beta(1)- or alpha(v)beta(3)-integrin to spread on fibronectin (FN) adsorbed to plastic. ECs in coculture lacked focal adhesions, but EC alpha(5)beta(1)-integrin bound to fibrillar FN on the SMC surface, promoting rapid fibrillar adhesion formation. As assessed by both Western blot analysis and quantitative real-time RT-PCR, coculture suppressed the expression of focal adhesion proteins and mRNA, whereas tensin protein and mRNA expression were elevated. When attached to polyacrylamide gels with similar elastic moduli as SMCs, focal adhesion formation and the rate of cell spreading increased relative to ECs in coculture. Thus, the elastic properties are only one factor contributing to EC spreading and focal adhesion formation in coculture. The results suggest that the softness of the SMCs and the fibrillar organization of FN inhibit focal adhesions and reduce cell spreading while promoting fibrillar adhesion formation. These changes in the type of adhesions may alter EC signaling pathways in tissue-engineered blood vessels.

  16. Bioprinting 3D cell-laden hydrogel microarray for screening human periodontal ligament stem cell response to extracellular matrix

    International Nuclear Information System (INIS)

    Ma, Yufei; Ji, Yuan; Huang, Guoyou; Zhang, Xiaohui; Xu, Feng; Ling, Kai

    2015-01-01

    Periodontitis is an inflammatory disease negatively affecting up to 15% of adults worldwide. Periodontal ligament stem cells (PDLSCs) hold great promises for periodontal tissue regeneration, where it is necessary to find proper extracellular matrix (ECM) materials (e.g., composition, concentration). In this study, we proposed a bioprinting-based approach to generate nano-liter sized three-dimensional (3D) cell-laden hydrogel array with gradient of ECM components, through controlling the volume ratio of two hydrogels, such as gelatin methacrylate (GelMA) and poly(ethylene glycol) (PEG) dimethacrylate. The resulting cell-laden array with a gradient of GelMA/PEG composition was used to screen human PDLSC response to ECM. The behavior (e.g., cell viability, spreading) of human PDLSCs in GelMA/PEG array were found to be depended on the volume ratios of GelMA/PEG, with cell viability and spreading area decreased along with increasing the ratio of PEG. The developed approach would be useful for screening cell-biomaterial interaction in 3D and promoting regeneration of functional tissue. (paper)

  17. Effect of Extracellular Zinc Chelator on Rat Retinal Ganglion Cell Number, and Taurine and Zinc Transporters in These Cells

    Directory of Open Access Journals (Sweden)

    Asarí Márquez García

    2017-05-01

    Full Text Available Zinc deficiency in humans causes decreased antioxidants in the retina and is related with abnormal darkness adaptation, cataracts, blindness, and macular degeneration. There is little information about the effects of zinc on the taurine system in mammalian retinal cells. Therefore, we studied the effect of zinc on the taurine transporter (TAUT and zinc transporters (ZnT-1 and 3 using the extracellular zinc chelator, diethylenetriaminepentaacetic acid (DTPA by fluorescence immunocytochemistry and immunohistochemistry in the ganglion cells (CG and cell layers of the retina of rats. Three days after administration of DTPA (10µM primary antibodies and secondary antibodies conjugated with rhodamine or fluorescein isothiocyanate (FITC were used as required. For immunocytochemical labeling approximately three hundred cells per condition were counted. For immunohistochemical labeling, the fluorescence intensity was measured as integrated optical density (DOI in four areas for each layer of tissue. DTPA produced a decrease of 32 % and 29 % in GC of the total cells labeled with antibody against glycoprotein Thy 1.1 and γ-synuclein, respectively. It also produced a significant decrease in TAUT localization in 27 and 28 % compared to controls. DTPA produced a decrease in the localization of ZnT-1 and ZnT-3 in the retina layers (ganglion cells, GCC and the outer and inner plexiform, CEP and CIP. The study of these molecules in the retina is relevant to understanding the interactions of taurine and zinc in this structure.

  18. Staurosporine and extracellular matrix proteins mediate the conversion of small cell lung carcinoma cells into a neuron-like phenotype.

    Directory of Open Access Journals (Sweden)

    Tamara Murmann

    Full Text Available Small cell lung carcinomas (SCLCs represent highly aggressive tumors with an overall five-year survival rate in the range of 5 to 10%. Here, we show that four out of five SCLC cell lines reversibly develop a neuron-like phenotype on extracellular matrix constituents such as fibronectin, laminin or thrombospondin upon staurosporine treatment in an RGD/integrin-mediated manner. Neurite-like processes extend rapidly with an average speed of 10 µm per hour. Depending on the cell line, staurosporine treatment affects either cell cycle arrest in G2/M phase or induction of polyploidy. Neuron-like conversion, although not accompanied by alterations in the expression pattern of a panel of neuroendocrine genes, leads to changes in protein expression as determined by two-dimensional gel electrophoresis. It is likely that SCLC cells already harbour the complete molecular repertoire to convert into a neuron-like phenotype. More extensive studies are needed to evaluate whether the conversion potential of SCLC cells is suitable for therapeutic interventions.

  19. Extracellular Vesicles from Adipose-Derived Mesenchymal Stem Cells Downregulate Senescence Features in Osteoarthritic Osteoblasts

    Directory of Open Access Journals (Sweden)

    Miguel Tofiño-Vian

    2017-01-01

    Full Text Available Osteoarthritis (OA affects all articular tissues leading to pain and disability. The dysregulation of bone metabolism may contribute to the progression of this condition. Adipose-derived mesenchymal stem cells (ASC are attractive candidates in the search of novel strategies for OA treatment and exert anti-inflammatory and cytoprotective effects on cartilage. Chronic inflammation in OA is a relevant factor in the development of cellular senescence and joint degradation. In this study, we extend our previous observations of ASC paracrine effects to study the influence of conditioned medium and extracellular vesicles from ASC on senescence induced by inflammatory stress in OA osteoblasts. Our results in cells stimulated with interleukin- (IL- 1β indicate that conditioned medium, microvesicles, and exosomes from ASC downregulate senescence-associated β-galactosidase activity and the accumulation of γH2AX foci. In addition, they reduced the production of inflammatory mediators, with the highest effect on IL-6 and prostaglandin E2. The control of mitochondrial membrane alterations and oxidative stress may provide a mechanism for the protective effects of ASC in OA osteoblasts. We have also shown that microvesicles and exosomes mediate the paracrine effects of ASC. Our study suggests that correction of abnormal osteoblast metabolism by ASC products may contribute to their protective effects.

  20. Naturally Occurring Extracellular Matrix Scaffolds for Dermal Regeneration: Do They Really Need Cells?

    Directory of Open Access Journals (Sweden)

    A. M. Eweida

    2015-01-01

    Full Text Available The pronounced effect of extracellular matrix (ECM scaffolds in supporting tissue regeneration is related mainly to their maintained 3D structure and their bioactive components. These decellularized matrix scaffolds could be revitalized before grafting via adding stem cells, fibroblasts, or keratinocytes to promote wound healing. We reviewed the online published literature in the last five years for the studies that performed ECM revitalization and discussed the results of these studies and the related literature. Eighteen articles met the search criteria. Twelve studies included adding cells to acellular dermal matrix (ADM, 3 studies were on small intestinal mucosa (SIS, one study was on urinary bladder matrix (UBM, one study was on amniotic membrane, and one study included both SIS and ADM loaded constructs. We believe that, in chronic and difficult-to-heal wounds, revitalizing the ECM scaffolds would be beneficial to overcome the defective host tissue interaction. This belief still has to be verified by high quality randomised clinical trials, which are still lacking in literature.

  1. Expression profiling of colorectal cancer cells reveals inhibition of DNA replication licensing by extracellular calcium.

    Science.gov (United States)

    Aggarwal, Abhishek; Schulz, Herbert; Manhardt, Teresa; Bilban, Martin; Thakker, Rajesh V; Kallay, Enikö

    2017-06-01

    Colorectal cancer is one of the most common cancers in industrialised societies. Epidemiological studies, animal experiments, and randomized clinical trials have shown that dietary factors can influence all stages of colorectal carcinogenesis, from initiation through promotion to progression. Calcium is one of the factors with a chemoprophylactic effect in colorectal cancer. The aim of this study was to understand the molecular mechanisms of the anti-tumorigenic effects of extracellular calcium ([Ca 2+ ] o ) in colon cancer cells. Gene expression microarray analysis of colon cancer cells treated for 1, 4, and 24h with 2mM [Ca 2+ ] o identified significant changes in expression of 1571 probe sets (ANOVA, pcalcium-sensing receptor (CaSR), a G protein-coupled receptor is a mediator involved in this process. To test whether these results were physiologically relevant, we fed mice with a standard diet containing low (0.04%), intermediate (0.1%), or high (0.9%) levels of dietary calcium. The main molecules regulating replication licensing were inhibited also in vivo, in the colon of mice fed high calcium diet. We show that among the mechanisms behind the chemopreventive effect of [Ca 2+ ] o is inhibition of replication licensing, a process often deregulated in neoplastic transformation. Our data suggest that dietary calcium is effective in preventing replicative stress, one of the main drivers of cancer and this process is mediated by the calcium-sensing receptor. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  2. Eosinophils Regulate Interferon Alpha Production in Plasmacytoid Dendritic Cells Stimulated with Components of Neutrophil Extracellular Traps.

    Science.gov (United States)

    Skrzeczynska-Moncznik, Joanna; Zabieglo, Katarzyna; Bossowski, Jozef P; Osiecka, Oktawia; Wlodarczyk, Agnieszka; Kapinska-Mrowiecka, Monika; Kwitniewski, Mateusz; Majewski, Pawel; Dubin, Adam; Cichy, Joanna

    2017-03-01

    Eosinophils constitute an important component of helminth immunity and are not only associated with various allergies but are also linked to autoinflammatory disorders, including the skin disease psoriasis. Here we demonstrate the functional relationship between eosinophils and plasmacytoid dendritic cells (pDCs) as related to skin diseases. We previously showed that pDCs colocalize with neutrophil extracellular traps (NETs) in psoriatic skin. Here we demonstrate that eosinophils are found in psoriatic skin near neutrophils and NETs, suggesting that pDC responses can be regulated by eosinophils. Eosinophils inhibited pDC function in vitro through a mechanism that did not involve cell contact but depended on soluble factors. In pDCs stimulated by specific NET components, eosinophil-conditioned media attenuated the production of interferon α (IFNα) but did not affect the maturation of pDCs as evidenced by the unaltered expression of the costimulatory molecules CD80 and CD86. As pDCs and IFNα play a key role in autoimmune skin inflammation, these data suggest that eosinophils may influence autoinflammatory responses through their impact on the production of IFNα by pDCs.

  3. Physical, Spatial, and Molecular Aspects of Extracellular Matrix of In Vivo Niches and Artificial Scaffolds Relevant to Stem Cells Research

    Directory of Open Access Journals (Sweden)

    Maria Akhmanova

    2015-01-01

    Full Text Available Extracellular matrix can influence stem cell choices, such as self-renewal, quiescence, migration, proliferation, phenotype maintenance, differentiation, or apoptosis. Three aspects of extracellular matrix were extensively studied during the last decade: physical properties, spatial presentation of adhesive epitopes, and molecular complexity. Over 15 different parameters have been shown to influence stem cell choices. Physical aspects include stiffness (or elasticity, viscoelasticity, pore size, porosity, amplitude and frequency of static and dynamic deformations applied to the matrix. Spatial aspects include scaffold dimensionality (2D or 3D and thickness; cell polarity; area, shape, and microscale topography of cell adhesion surface; epitope concentration, epitope clustering characteristics (number of epitopes per cluster, spacing between epitopes within cluster, spacing between separate clusters, cluster patterns, and level of disorder in epitope arrangement, and nanotopography. Biochemical characteristics of natural extracellular matrix molecules regard diversity and structural complexity of matrix molecules, affinity and specificity of epitope interaction with cell receptors, role of non-affinity domains, complexity of supramolecular organization, and co-signaling by growth factors or matrix epitopes. Synergy between several matrix aspects enables stem cells to retain their function in vivo and may be a key to generation of long-term, robust, and effective in vitro stem cell culture systems.

  4. Aging of the skeletal muscle extracellular matrix drives a stem cell fibrogenic conversion.

    Science.gov (United States)

    Stearns-Reider, Kristen M; D'Amore, Antonio; Beezhold, Kevin; Rothrauff, Benjamin; Cavalli, Loredana; Wagner, William R; Vorp, David A; Tsamis, Alkiviadis; Shinde, Sunita; Zhang, Changqing; Barchowsky, Aaron; Rando, Thomas A; Tuan, Rocky S; Ambrosio, Fabrisia

    2017-06-01

    Age-related declines in skeletal muscle regeneration have been attributed to muscle stem cell (MuSC) dysfunction. Aged MuSCs display a fibrogenic conversion, leading to fibrosis and impaired recovery after injury. Although studies have demonstrated the influence of in vitro substrate characteristics on stem cell fate, whether and how aging of the extracellular matrix (ECM) affects stem cell behavior has not been investigated. Here, we investigated the direct effect of the aged muscle ECM on MuSC lineage specification. Quantification of ECM topology and muscle mechanical properties reveals decreased collagen tortuosity and muscle stiffening with increasing age. Age-related ECM alterations directly disrupt MuSC responses, and MuSCs seeded ex vivo onto decellularized ECM constructs derived from aged muscle display increased expression of fibrogenic markers and decreased myogenicity, compared to MuSCs seeded onto young ECM. This fibrogenic conversion is recapitulated in vitro when MuSCs are seeded directly onto matrices elaborated by aged fibroblasts. When compared to young fibroblasts, fibroblasts isolated from aged muscle display increased nuclear levels of the mechanosensors, Yes-associated protein (YAP)/transcriptional coactivator with PDZ-binding motif (TAZ), consistent with exposure to a stiff microenvironment in vivo. Accordingly, preconditioning of young fibroblasts by seeding them onto a substrate engineered to mimic the stiffness of aged muscle increases YAP/TAZ nuclear translocation and promotes secretion of a matrix that favors MuSC fibrogenesis. The findings here suggest that an age-related increase in muscle stiffness drives YAP/TAZ-mediated pathogenic expression of matricellular proteins by fibroblasts, ultimately disrupting MuSC fate. © 2017 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

  5. Ornamenting 3D printed scaffolds with cell-laid extracellular matrix for bone tissue regeneration.

    Science.gov (United States)

    Pati, Falguni; Song, Tae-Ha; Rijal, Girdhari; Jang, Jinah; Kim, Sung Won; Cho, Dong-Woo

    2015-01-01

    3D printing technique is the most sophisticated technique to produce scaffolds with tailorable physical properties. But, these scaffolds often suffer from limited biological functionality as they are typically made from synthetic materials. Cell-laid mineralized ECM was shown to be potential for improving the cellular responses and drive osteogenesis of stem cells. Here, we intend to improve the biological functionality of 3D-printed synthetic scaffolds by ornamenting them with cell-laid mineralized extracellular matrix (ECM) that mimics a bony microenvironment. We developed bone graft substitutes by using 3D printed scaffolds made from a composite of polycaprolactone (PCL), poly(lactic-co-glycolic acid) (PLGA), and β-tricalcium phosphate (β-TCP) and mineralized ECM laid by human nasal inferior turbinate tissue-derived mesenchymal stromal cells (hTMSCs). A rotary flask bioreactor was used to culture hTMSCs on the scaffolds to foster formation of mineralized ECM. A freeze/thaw cycle in hypotonic buffer was used to efficiently decellularize (97% DNA reduction) the ECM-ornamented scaffolds while preserving its main organic and inorganic components. The ECM-ornamented 3D printed scaffolds supported osteoblastic differentiation of newly-seeded hTMSCs by upregulating four typical osteoblastic genes (4-fold higher RUNX2; 3-fold higher ALP; 4-fold higher osteocalcin; and 4-fold higher osteopontin) and increasing calcium deposition compared to bare 3D printed scaffolds. In vivo, in ectopic and orthotopic models in rats, ECM-ornamented scaffolds induced greater bone formation than that of bare scaffolds. These results suggest a valuable method to produce ECM-ornamented 3D printed scaffolds as off-the-shelf bone graft substitutes that combine tunable physical properties with physiological presentation of biological signals. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Effects of extracellular pH on UV-induced K+ efflux from cultured rose cells

    International Nuclear Information System (INIS)

    Huerta, A.J.; Murphy, T.M.

    1989-01-01

    Ultraviolet (UV) light causes a specific leakage of K + from cultured rose cells (Rosa damascena). During K + efflux, there is also an increase in extracellular HCO 3 - and acidification of the cell interior. We hypothesized that the HCO 3 - originated from intracellular hydration of respiratory CO 2 and served as a charge balancing mechanism during K + efflux, the K + and HCO 3 - being co transported out of the cell through specific channels. An alternative hypothesis which would yield similar results would be the counter transport of K + and H + . To test these hypotheses, we studied the effect of a range of external pH values (pH 5-9), regulated by various methods (pH-stat, 100 millimolar Tris-Mes buffer, or CO 2 partial pressure), on the UV-induced K + efflux. Both UV-C (less than 290 nanometers) and UV-B (290-310 nanometers) induced K + efflux with a minimum at about pH 6 to 7, and greater efflux at pH values of 5, 8, and 9. Since pH values of 8 and 9 increased instead of reduced the efflux of K + , these data are not consistent with notion that the efflux of K + is dependent on an influx of H + , a process that would be sensitive to external H + concentration. We suggest that the effect of pH on K + efflux may be mediated through the titration of specific K + -transporting proteins or channels in the plasma membrane. Since we could not detect the presence of carbonic anhydrase activity in cell extracts, we could not use the location of this enzyme to aid in our interpretation regarding the site of hydration of CO 2 . (author)

  7. The external face of Candida albicans: A proteomic view of the cell surface and the extracellular environment.

    Science.gov (United States)

    Gil-Bona, Ana; Amador-García, Ahinara; Gil, Concha; Monteoliva, Lucia

    2018-05-30

    The cell surface and secreted proteins are the initial points of contact between Candida albicans and the host. Improvements in protein extraction approaches and mass spectrometers have allowed researchers to obtain a comprehensive knowledge of these external subproteomes. In this paper, we review the published proteomic studies that have examined C. albicans extracellular proteins, including the cell surface proteins or surfome and the secreted proteins or secretome. The use of different approaches to isolate cell wall and cell surface proteins, such as fractionation approaches or cell shaving, have resulted in different outcomes. Proteins with N-terminal signal peptide, known as classically secreted proteins, and those that lack the signal peptide, known as unconventionally secreted proteins, have been consistently identified. Existing studies on C. albicans extracellular vesicles reveal that they are relevant as an unconventional pathway of protein secretion and can help explain the presence of proteins without a signal peptide, including some moonlighting proteins, in the cell wall and the extracellular environment. According to the global view presented in this review, cell wall proteins, virulence factors such as adhesins or hydrolytic enzymes, metabolic enzymes and stress related-proteins are important groups of proteins in C. albicans surfome and secretome. Candida albicans extracellular proteins are involved in biofilm formation, cell nutrient acquisition and cell wall integrity maintenance. Furthermore, these proteins include virulence factors and immunogenic proteins. This review is of outstanding interest, not only because it extends knowledge of the C. albicans surface and extracellular proteins that could be related with pathogenesis, but also because it presents insights that may facilitate the future development of new antifungal drugs and vaccines and contributes to efforts to identify new biomarkers that can be employed to diagnose candidiasis

  8. Action potentials in retinal ganglion cells are initiated at the site of maximal curvature of the extracellular potential.

    Science.gov (United States)

    Eickenscheidt, Max; Zeck, Günther

    2014-06-01

    The initiation of an action potential by extracellular stimulation occurs after local depolarization of the neuronal membrane above threshold. Although the technique shows remarkable clinical success, the site of action and the relevant stimulation parameters are not completely understood. Here we identify the site of action potential initiation in rabbit retinal ganglion cells (RGCs) interfaced to an array of extracellular capacitive stimulation electrodes. We determine which feature of the extracellular potential governs action potential initiation by simultaneous stimulation and recording RGCs interfaced in epiretinal configuration. Stimulation electrodes were combined to areas of different size and were presented at different positions with respect to the RGC. Based on stimulation by electrodes beneath the RGC soma and simultaneous sub-millisecond latency measurement we infer axonal initiation at the site of maximal curvature of the extracellular potential. Stimulation by electrodes at different positions along the axon reveals a nearly constant threshold current density except for a narrow region close to the cell soma. These findings are explained by the concept of the activating function modified to consider a region of lower excitability close to the cell soma. We present a framework how to estimate the site of action potential initiation and the stimulus required to cross threshold in neurons tightly interfaced to capacitive stimulation electrodes. Our results underscore the necessity of rigorous electrical characterization of the stimulation electrodes and of the interfaced neural tissue.

  9. IFN-γ Induces Mimic Extracellular Trap Cell Death in Lung Epithelial Cells Through Autophagy-Regulated DNA Damage.

    Science.gov (United States)

    Lin, Chiou-Feng; Chien, Shun-Yi; Chen, Chia-Ling; Hsieh, Chia-Yuan; Tseng, Po-Chun; Wang, Yu-Chih

    2016-02-01

    Treatment of interferon-γ (IFN-γ) causes cell growth inhibition and cytotoxicity in lung epithelial malignancies. Regarding the induction of autophagy related to IFN-γ signaling, this study investigated the link between autophagy and IFN-γ cytotoxicity. In A549 human lung cancer cells, IFN-γ treatment induced concurrent apoptotic and nonapoptotic events. Unexpectedly, the nonapoptotic cells present mimic extracellular trap cell death (ETosis), which was regulated by caspase-3 and by autophagy induction through immunity-related GTPase family M protein 1 and activating transcription factor 6. Furthermore, IFN-γ signaling controlled mimic ETosis through a mechanism involving an autophagy- and Fas-associated protein with death domain-controlled caspase-8/-3 activation. Following caspase-mediated lamin degradation, IFN-γ caused DNA damage-associated ataxia telangiectasia and Rad3-related protein (ATR)/ataxia telangiectasia mutated (ATM)-regulated mimic ETosis. Upon ATR/ATM signaling, peptidyl arginine deiminase 4 (PAD4)-mediated histone 3 citrullination promoted mimic ETosis. Such IFN-γ-induced effects were defective in PC14PE6/AS2 human lung cancer cells, which were unsusceptible to IFN-γ-induced autophagy. Due to autophagy-based caspase cascade activation, IFN-γ triggers unconventional caspase-mediated DNA damage, followed by ATR/ATM-regulated PAD4-mediated histone citrullination during mimic ETosis in lung epithelial malignancy.

  10. SU-F-SPS-08: Measuring the Interaction Of DDR Cell Receptors and Extracellular Matrix Collagen in Prostate Cells

    Energy Technology Data Exchange (ETDEWEB)

    Dong, J; Sarkar, A; Hoffmann, P [Wayne State University, Detroit, MI (United States); Suhail, A; Fridman, R [Wayne State University School of Medicine, Detroit, MI (United States)

    2016-06-15

    Purpose: Discoidin domain receptors (DDR) have recently been recognized as important players in cancer progression. DDRs are cell receptors that interact with collagen, an extracellular matrix (ECM) protein. However the detailed mechanism of their interaction is unclear. Here we attempted to examine their interaction in terms of structural (surface topography), mechanical (rupture force), and kinetic (binding probability) information on the single molecular scale with the use of atomic force microscopy (AFM). Methods: The Quantitative Nano-mechanical property Mapping (QNM) mode of AFM allowed to assess the cells in liquid growth media at their optimal physiological while being viable. Human benign prostate hyperplasia (BPH-1) cell line was genetically regulated to suppress DDR expression (DDR- cells) and was compared with naturally DDR expressing cells (DDR+). Results: Binding force measurements (n = 1000) were obtained before and after the two groups were treated with fibronectin (FN), an integrin-inhibiting antibody to block the binding of integrin. The quantification indicates that cells containing DDR bind with collagen at a most probable force of 80.3–83.0 ±7.6 pN. The probability of them binding is 0.167 when other interactions (mainly due to integrin-collagen binding) are minimized. Conclusion: Together with further force measurements at different pulling speeds will determine dissociation rate, binding distance and activation barrier. These parameters in benign cells provides some groundwork in understanding DDR’s behavior in various cell microenvironments such as in malignant tumor cells. Funding supported by Richard Barber Interdisciplinary Research Program of Wayne State University.

  11. SU-F-SPS-08: Measuring the Interaction Of DDR Cell Receptors and Extracellular Matrix Collagen in Prostate Cells

    International Nuclear Information System (INIS)

    Dong, J; Sarkar, A; Hoffmann, P; Suhail, A; Fridman, R

    2016-01-01

    Purpose: Discoidin domain receptors (DDR) have recently been recognized as important players in cancer progression. DDRs are cell receptors that interact with collagen, an extracellular matrix (ECM) protein. However the detailed mechanism of their interaction is unclear. Here we attempted to examine their interaction in terms of structural (surface topography), mechanical (rupture force), and kinetic (binding probability) information on the single molecular scale with the use of atomic force microscopy (AFM). Methods: The Quantitative Nano-mechanical property Mapping (QNM) mode of AFM allowed to assess the cells in liquid growth media at their optimal physiological while being viable. Human benign prostate hyperplasia (BPH-1) cell line was genetically regulated to suppress DDR expression (DDR- cells) and was compared with naturally DDR expressing cells (DDR+). Results: Binding force measurements (n = 1000) were obtained before and after the two groups were treated with fibronectin (FN), an integrin-inhibiting antibody to block the binding of integrin. The quantification indicates that cells containing DDR bind with collagen at a most probable force of 80.3–83.0 ±7.6 pN. The probability of them binding is 0.167 when other interactions (mainly due to integrin-collagen binding) are minimized. Conclusion: Together with further force measurements at different pulling speeds will determine dissociation rate, binding distance and activation barrier. These parameters in benign cells provides some groundwork in understanding DDR’s behavior in various cell microenvironments such as in malignant tumor cells. Funding supported by Richard Barber Interdisciplinary Research Program of Wayne State University

  12. Planar cell polarity proteins differentially regulate extracellular matrix organization and assembly during zebrafish gastrulation.

    Science.gov (United States)

    Dohn, Michael R; Mundell, Nathan A; Sawyer, Leah M; Dunlap, Julie A; Jessen, Jason R

    2013-11-01

    Zebrafish gastrulation cell movements occur in the context of dynamic changes in extracellular matrix (ECM) organization and require the concerted action of planar cell polarity (PCP) proteins that regulate cell elongation and mediolateral alignment. Data obtained using Xenopus laevis gastrulae have shown that integrin-fibronectin interactions underlie the formation of polarized cell protrusions necessary for PCP and have implicated PCP proteins themselves as regulators of ECM. By contrast, the relationship between establishment of PCP and ECM assembly/remodeling during zebrafish gastrulation is unclear. We previously showed that zebrafish embryos carrying a null mutation in the four-pass transmembrane PCP protein vang-like 2 (vangl2) exhibit increased matrix metalloproteinase activity and decreased immunolabeling of fibronectin. These data implicated for the first time a core PCP protein in the regulation of pericellular proteolysis of ECM substrates and raised the question of whether other zebrafish PCP proteins also impact ECM organization. In Drosophila melanogaster, the cytoplasmic PCP protein Prickle binds Van Gogh and regulates its function. Here we report that similar to vangl2, loss of zebrafish prickle1a decreases fibronectin protein levels in gastrula embryos. We further show that Prickle1a physically binds Vangl2 and regulates both the subcellular distribution and total protein level of Vangl2. These data suggest that the ability of Prickle1a to impact fibronectin organization is at least partly due to effects on Vangl2. In contrast to loss of either Vangl2 or Prickle1a function, we find that glypican4 (a Wnt co-receptor) and frizzled7 mutant gastrula embryos with disrupted non-canonical Wnt signaling exhibit the opposite phenotype, namely increased fibronectin assembly. Our data show that glypican4 mutants do not have decreased proteolysis of ECM substrates, but instead have increased cell surface cadherin protein expression and increased intercellular

  13. Extracellular cell wall β(1,3)glucan is required to couple septation to actomyosin ring contraction

    Science.gov (United States)

    Muñoz, Javier; Cortés, Juan Carlos G.; Sipiczki, Matthias; Ramos, Mariona; Clemente-Ramos, José Angel; Moreno, M. Belén; Martins, Ivone M.; Pérez, Pilar

    2013-01-01

    Cytokinesis has been extensively studied in different models, but the role of the extracellular cell wall is less understood. Here we studied this process in fission yeast. The essential protein Bgs4 synthesizes the main cell wall β(1,3)glucan. We show that Bgs4-derived β(1,3)glucan is required for correct and stable actomyosin ring positioning in the cell middle, before the start of septum formation and anchorage to the cell wall. Consequently, β(1,3)glucan loss generated ring sliding, oblique positioned rings and septa, misdirected septum synthesis indicative of relaxed rings, and uncoupling between a fast ring and membrane ingression and slow septum synthesis, suggesting that cytokinesis can progress with defective septum pushing and/or ring pulling forces. Moreover, Bgs4-derived β(1,3)glucan is essential for secondary septum formation and correct primary septum completion. Therefore, our results show that extracellular β(1,3)glucan is required for cytokinesis to connect the cell wall with the plasma membrane and for contractile ring function, as proposed for the equivalent extracellular matrix in animal cells. PMID:24165938

  14. Regulation of human mesenchymal stem cells differentiation into chondrocytes in extracellular matrix-based hydrogel scaffolds.

    Science.gov (United States)

    Du, Mingchun; Liang, Hui; Mou, Chenchen; Li, Xiaoran; Sun, Jie; Zhuang, Yan; Xiao, Zhifeng; Chen, Bing; Dai, Jianwu

    2014-02-01

    To induce human mesenchymal stem cells (hMSCs) to differentiate into chondrocytes in three-dimensional (3D) microenvironments, we developed porous hydrogel scaffolds using the cartilage extracellular matrix (ECM) components of chondroitin sulfate (CS) and collagen (COL). The turbidity and viscosity experiments indicated hydrogel could form through pH-triggered co-precipitation when pH=2-3. Enzyme-linked immunosorbent assay (ELISA) confirmed the hydrogel scaffolds could controllably release growth factors as envisaged. Transforming growth factor-β (TGF-β) was released to stimulate hMSCs differentiation into chondrocytes; and then collagen binding domain-basic fibroblast growth factor (CBD-bFGF) was released to improve the differentiation and preserve the chondrocyte phenotype. In in vitro cell culture experiments, the differentiation processes were compared in different microenvironments: 2D culture in culture plate as control, 3D culture in the fabricated scaffolds without growth factors (CC), the samples with CBD-bFGF (CC-C), the samples with TGF-β (CC-T), the samples with CBD-bFGF/TGF-β (CC-CT). Real-time polymerase chain reaction (RT-PCR) revealed the hMSC marker genes of CD44 and CD105 decreased; at the same time the chondrocyte marker genes of collagen type II and aggrecan increased, especially in the CC-CT sample. Immunostaining results further confirmed the hMSC marker protein of CD 44 disappeared and the chondrocyte marker protein of collagen type II emerged over time in the CC-CT sample. These results imply the ECM-based hydrogel scaffolds with growth factors can supply suitable 3D cell niches for hMSCs differentiation into chondrocytes and the differentiation process can be regulated by the controllably released growth factors. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. On-chip immunoelectrophoresis of extracellular vesicles released from human breast cancer cells.

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    Takanori Akagi

    Full Text Available Extracellular vesicles (EVs including exosomes and microvesicles have attracted considerable attention in the fields of cell biology and medicine. For a better understanding of EVs and further exploration of their applications, the development of analytical methods for biological nanovesicles has been required. In particular, considering the heterogeneity of EVs, methods capable of measuring individual vesicles are desired. Here, we report that on-chip immunoelectrophoresis can provide a useful method for the differential protein expression profiling of individual EVs. Electrophoresis experiments were performed on EVs collected from the culture supernatant of MDA-MB-231 human breast cancer cells using a measurement platform comprising a microcapillary electrophoresis chip and a laser dark-field microimaging system. The zeta potential distribution of EVs that reacted with an anti-human CD63 (exosome and microvesicle marker antibody showed a marked positive shift as compared with that for the normal immunoglobulin G (IgG isotype control. Thus, on-chip immunoelectrophoresis could sensitively detect the over-expression of CD63 glycoproteins on EVs. Moreover, to explore the applicability of on-chip immunoelectrophoresis to cancer diagnosis, EVs collected from the blood of a mouse tumor model were analyzed by this method. By comparing the zeta potential distributions of EVs after their immunochemical reaction with normal IgG, and the anti-human CD63 and anti-human CD44 (cancer stem cell marker antibodies, EVs of tumor origin circulating in blood were differentially detected in the real sample. The result indicates that the present method is potentially applicable to liquid biopsy, a promising approach to the low-invasive diagnosis of cancer.

  16. Endocytosis of collagen by hepatic stellate cells regulates extracellular matrix dynamics.

    Science.gov (United States)

    Bi, Yan; Mukhopadhyay, Dhriti; Drinane, Mary; Ji, Baoan; Li, Xing; Cao, Sheng; Shah, Vijay H

    2014-10-01

    Hepatic stellate cells (HSCs) generate matrix, which in turn may also regulate HSCs function during liver fibrosis. We hypothesized that HSCs may endocytose matrix proteins to sense and respond to changes in microenvironment. Primary human HSCs, LX2, or mouse embryonic fibroblasts (MEFs) [wild-type; c-abl(-/-); or Yes, Src, and Fyn knockout mice (YSF(-/-))] were incubated with fluorescent-labeled collagen or gelatin. Fluorescence-activated cell sorting analysis and confocal microscopy were used for measuring cellular internalization of matrix proteins. Targeted PCR array and quantitative real-time PCR were used to evaluate gene expression changes. HSCs and LX2 cells endocytose collagens in a concentration- and time-dependent manner. Endocytosed collagen colocalized with Dextran 10K, a marker of macropinocytosis, and 5-ethylisopropyl amiloride, an inhibitor of macropinocytosis, reduced collagen internalization by 46%. Cytochalasin D and ML7 blocked collagen internalization by 47% and 45%, respectively, indicating that actin and myosin are critical for collagen endocytosis. Wortmannin and AKT inhibitor blocked collagen internalization by 70% and 89%, respectively, indicating that matrix macropinocytosis requires phosphoinositide-3-kinase (PI3K)/AKT signaling. Overexpression of dominant-negative dynamin-2 K44A blocked matrix internalization by 77%, indicating a role for dynamin-2 in matrix macropinocytosis. Whereas c-abl(-/-) MEF showed impaired matrix endocytosis, YSF(-/-) MEF surprisingly showed increased matrix endocytosis. It was also associated with complex gene regulations that related with matrix dynamics, including increased matrix metalloproteinase 9 (MMP-9) mRNA levels and zymographic activity. HSCs endocytose matrix proteins through macropinocytosis that requires a signaling network composed of PI3K/AKT, dynamin-2, and c-abl. Interaction with extracellular matrix regulates matrix dynamics through modulating multiple gene expressions including MMP-9

  17. Extracellular vesicles from human liver stem cells restore argininosuccinate synthase deficiency.

    Science.gov (United States)

    Herrera Sanchez, Maria Beatriz; Previdi, Sara; Bruno, Stefania; Fonsato, Valentina; Deregibus, Maria Chiara; Kholia, Sharad; Petrillo, Sara; Tolosano, Emanuela; Critelli, Rossana; Spada, Marco; Romagnoli, Renato; Salizzoni, Mauro; Tetta, Ciro; Camussi, Giovanni

    2017-07-27

    Argininosuccinate synthase (ASS)1 is a urea cycle enzyme that catalyzes the conversion of citrulline and aspartate to argininosuccinate. Mutations in the ASS1 gene cause citrullinemia type I, a rare autosomal recessive disorder characterized by neonatal hyperammonemia, elevated citrulline levels, and early neonatal death. Treatment for this disease is currently restricted to liver transplantation; however, due to limited organ availability, substitute therapies are required. Recently, extracellular vesicles (EVs) have been reported to act as intercellular transporters carrying genetic information responsible for cell reprogramming. In previous studies, we isolated a population of stem cell-like cells known as human liver stem cells (HLSCs) from healthy liver tissue. Moreover, EVs derived from HLSCs were reported to exhibit regenerative effects on the liver parenchyma in models of acute liver injury. The aim of this study was to evaluate whether EVs derived from normal HLSCs restored ASS1 enzymatic activity and urea production in hepatocytes differentiated from HLSCs derived from a patient with type I citrullinemia. HLSCs were isolated from the liver of a patient with type I citrullinemia (ASS1-HLSCs) and characterized by fluorescence-activated cell sorting (FACS), immunofluorescence, and DNA sequencing analysis. Furthermore, their differentiation capabilities in vitro were also assessed. Hepatocytes differentiated from ASS1-HLSCs were evaluated by the production of urea and ASS enzymatic activity. EVs derived from normal HLSCs were purified by differential ultracentrifugation followed by floating density gradient. The EV content was analyzed to identify the presence of ASS1 protein, mRNA, and ASS1 gene. In order to obtain ASS1-depleted EVs, a knockdown of the ASS1 gene in HLSCs was performed followed by EV isolation from these cells. Treating ASS1-HLSCs with EVs from HLSCs restored both ASS1 activity and urea production mainly through the transfer of ASS1 enzyme

  18. Mast cells limit extracellular levels of IL-13 via a serglycin proteoglycan-serine protease axis.

    Science.gov (United States)

    Waern, Ida; Karlsson, Iulia; Thorpe, Michael; Schlenner, Susan M; Feyerabend, Thorsten B; Rodewald, Hans-Reimer; Åbrink, Magnus; Hellman, Lars; Pejler, Gunnar; Wernersson, Sara

    2012-12-01

    Mast cell (MC) granules contain large amounts of proteases of the chymase, tryptase and carboxypeptidase A (MC-CPA) type that are stored in complex with serglycin,a proteoglycan with heparin side chains. Hence, serglycinprotease complexes are released upon MC degranulation and may influence local inflammation. Here we explored the possibility that a serglycin-protease axis may regulate levels of IL-13, a cytokine involved in allergic asthma. Indeed, we found that wild-type MCs efficiently degraded exogenous or endogenously produced IL-13 upon degranulation,whereas serglycin −/− MCs completely lacked this ability.Moreover, MC-mediated IL-13 degradation was blocked both by a serine protease inhibitor and by a heparin antagonist,which suggests that IL-13 degradation is catalyzed by serglycin-dependent serine proteases and that optimal IL-13 degradation is dependent on both the serglycin and the protease component of the serglycin-protease complex.Moreover, IL-13 degradation was abrogated in MC-CPA −/−MC cultures, but was normal in cultures of MCs with an inactivating mutation of MC-CPA, which suggests that the IL-13-degrading serine proteases rely on MC-CPA protein.Together, our data implicate a serglycin-serine protease axis in the regulation of extracellular levels of IL-13. Reduction of IL-13 levels through this mechanism possibly can provide a protective function in the context of allergic inflammation.

  19. Mesenchymal stem cells can survive on the extracellular matrix-derived decellularized bovine articular cartilage scaffold

    Directory of Open Access Journals (Sweden)

    Amin Tavassoli

    2015-12-01

    Full Text Available Objective (s: The scarcity of articular cartilage defect to repair due to absence of blood vessels and tissue engineering is one of the promising approaches for cartilage regeneration. The objective of this study was to prepare an extracellular matrix derived decellularized bovine articular cartilage scaffold and investigate its interactions with seeded rat bone marrow mesenchymal stem cells (BM-MSCs. Materials and Methods: Bovine articular cartilage that was cut into pieces with 2 mm thickness, were decellularized by combination of physical and chemical methods including snap freeze-thaw and treatment with sodium dodecyl sulfate (SDS. The scaffolds were then seeded with 1, 1’-dioctadecyl-3, 3, 3’, 3’-tetramethylindocarbocyanine perchlorate (DiI labeled BM-MSCs and cultured for up to two weeks. Results: Histological studies of decellularized bovine articular cartilage showed that using 5 cycles of snap freeze-thaw in liquid nitrogen and treatment with 2.5% SDS for 4 hr led to the best decellularization, while preserving the articular cartilage structure. Adherence and penetration of seeded BM-MSCs on to the scaffold were displayed by histological and florescence examinations and also confirmed by electron microscopy. Conclusion: ECM-derived decellularized articular cartilage scaffold provides a suitable environment to support adhesion and maintenance of cultured BM-MSCs and could be applied to investigate cellular behaviors in this system and may also be useful for studies of cartilage tissue engineering.

  20. Intravital Confocal and Two-photon Imaging of Dual-color Cells and Extracellular Matrix Mimics

    Science.gov (United States)

    Bal, Ufuk; Andresen, Volker; Baggett, Brenda; Utzinger, Urs

    2013-01-01

    To optimize imaging of cells in three dimensional culture we studied confocal backscattering, Second Harmonic Generation (SHG) and autofluorescence as source of contrast in extracellular matrix (ECM) mimics and evaluated the attenuation as well as bleaching of endogenous cellular fluorescence signals. All common ECM mimics exhibit contrast observable with confocal reflectance microscopy. SHG imaging on collagen I based hydrogels provides high contrast and good optical penetration depth. Agarose is a useful embedding medium because it allows for large optical penetration and exhibits minimal autofluorescence while still providing good reflectance to detect voids in the embedding medium. We labeled breast cancer cells’ outline with DsRed2 and nucleus with eGFP. DsRed2 can be excited with confocal imaging at 568nm, and with two photon excitation (TPE) in the red and longer NIR. eGFP was excited at 488nm for confocal and in the NIR for TPE. While there is small difference in the bleaching rate for eGFP between confocal and TPE we observed significant difference for DsRed2 where bleaching is strongest during TPE in the red wavelengths and smallest during confocal imaging. After a few hundred microns depth in a collagen I hydrogel, TPE fluorescence becomes twice as strong compared to confocal imaging. PMID:23380006

  1. Interleukin-13 conjugated quantum dots for identification of glioma initiating cells and their extracellular vesicles.

    Science.gov (United States)

    Madhankumar, A B; Mrowczynski, Oliver D; Patel, Suhag R; Weston, Cody L; Zacharia, Brad E; Glantz, Michael J; Siedlecki, Christopher A; Xu, Li-Chong; Connor, James R

    2017-08-01

    cells and tissues. In this study we designed a cytokine (interleukin-13) functionalized quantum dot to detect a cancer associated receptor expressed in cancer stem cells and the extracellular vesicles (exosomes) secreted by the cancer cells themselves. The binding pattern of these cytokine modified quantum dots to the cancer stem cells and exosomes alters the physical properties of the complex in the fixed and suspended form. This altered binding pattern can be monitored by a variety of techniques, including transmission electron microscopy, atomic force microscopy and flow cytometry, and subsequent characterization of this quantum dot binding profile provides useful data that can be utilized as a fingerprint to detect cancer disease progression. This type of functionalized quantum dot fingerprint is especially useful for invasive cancers including brain and other metastatic cancers and may allow for earlier detection of disease progression or recurrence, thus saving the lives of patients suffering from this devastating disease. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  2. Oxidative Stress Facilitates IFN-γ-Induced Mimic Extracellular Trap Cell Death in A549 Lung Epithelial Cancer Cells.

    Science.gov (United States)

    Lin, Chiou-Feng; Chen, Chia-Ling; Chien, Shun-Yi; Tseng, Po-Chun; Wang, Yu-Chih; Tsai, Tsung-Ting

    2016-01-01

    We previously demonstrated that IFN-γ induces an autophagy-regulated mimic extracellular trap cell death (ETosis) in A549 human lung cancer cells. Regarding reactive oxygen species (ROS) are involved in ETosis, this study investigated the role of oxidative stress. After IFN-γ stimulation, a necrosis-like cell death mimic ETosis occurred accompanied by the inhibition of cell growth, aberrant nuclear staining, and nucleosome release. ROS were generated in a time-dependent manner with an increase in NADPH oxidase component protein expression. STAT1-mediated IFN regulatory factor-1 activation was essential for upregulating ROS production. By genetically silencing p47phox, IFN-γ-induced ROS and mimic ETosis were significantly attenuated. This mechanistic study indicated that ROS may mediate DNA damage followed by histone H3 citrullination. Furthermore, ROS promoted IFN-γ-induced mimic ETosis in cooperation with autophagy. These findings further demonstrate that ROS regulates IFN-γ-induced mimic ETosis in lung epithelial malignancy.

  3. The SULFs, extracellular sulfatases for heparan sulfate, promote the migration of corneal epithelial cells during wound repair.

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    Inna Maltseva

    Full Text Available Corneal epithelial wound repair involves the migration of epithelial cells to cover the defect followed by the proliferation of the cells to restore thickness. Heparan sulfate proteoglycans (HSPGs are ubiquitous extracellular molecules that bind to a plethora of growth factors, cytokines, and morphogens and thereby regulate their signaling functions. Ligand binding by HS chains depends on the pattern of four sulfation modifications, one of which is 6-O-sulfation of glucosamine (6OS. SULF1 and SULF2 are highly homologous, extracellular endosulfatases, which post-synthetically edit the sulfation status of HS by removing 6OS from intact chains. The SULFs thereby modulate multiple signaling pathways including the augmentation of Wnt/ß-catenin signaling. We found that wounding of mouse corneal epithelium stimulated SULF1 expression in superficial epithelial cells proximal to the wound edge. Sulf1⁻/⁻, but not Sulf2⁻/⁻, mice, exhibited a marked delay in healing. Furthermore, corneal epithelial cells derived from Sulf1⁻/⁻ mice exhibited a reduced rate of migration in repair of a scratched monolayer compared to wild-type cells. In contrast, human primary corneal epithelial cells expressed SULF2, as did a human corneal epithelial cell line (THCE. Knockdown of SULF2 in THCE cells also slowed migration, which was restored by overexpression of either mouse SULF2 or human SULF1. The interchangeability of the two SULFs establishes their capacity for functional redundancy. Knockdown of SULF2 decreased Wnt/ß-catenin signaling in THCE cells. Extracellular antagonists of Wnt signaling reduced migration of THCE cells. However in SULF2- knockdown cells, these antagonists exerted no further effects on migration, consistent with the SULF functioning as an upstream regulator of Wnt signaling. Further understanding of the mechanistic action of the SULFs in promoting corneal repair may lead to new therapeutic approaches for the treatment of corneal injuries.

  4. The role of extracellular conductivity profiles in compartmental models for neurons: particulars for layer 5 pyramidal cells.

    Science.gov (United States)

    Wang, Kai; Riera, Jorge; Enjieu-Kadji, Herve; Kawashima, Ryuta

    2013-07-01

    With the rapid increase in the number of technologies aimed at observing electric activity inside the brain, scientists have felt the urge to create proper links between intracellular- and extracellular-based experimental approaches. Biophysical models at both physical scales have been formalized under assumptions that impede the creation of such links. In this work, we address this issue by proposing a multicompartment model that allows the introduction of complex extracellular and intracellular resistivity profiles. This model accounts for the geometrical and electrotonic properties of any type of neuron through the combination of four devices: the integrator, the propagator, the 3D connector, and the collector. In particular, we applied this framework to model the tufted pyramidal cells of layer 5 (PCL5) in the neocortex. Our model was able to reproduce the decay and delay curves of backpropagating action potentials (APs) in this type of cell with better agreement with experimental data. We used the voltage drops of the extracellular resistances at each compartment to approximate the local field potentials generated by a PCL5 located in close proximity to linear microelectrode arrays. Based on the voltage drops produced by backpropagating APs, we were able to estimate the current multipolar moments generated by a PCL5. By adding external current sources in parallel to the extracellular resistances, we were able to create a sensitivity profile of PCL5 to electric current injections from nearby microelectrodes. In our model for PCL5, the kinetics and spatial profile of each ionic current were determined based on a literature survey, and the geometrical properties of these cells were evaluated experimentally. We concluded that the inclusion of the extracellular space in the compartmental models of neurons as an extra electrotonic medium is crucial for the accurate simulation of both the propagation of the electric potentials along the neuronal dendrites and the

  5. Extracellular vesicles secreted from cancer cell lines stimulate secretion of MMP-9, IL-6, TGF-β1 and EMMPRIN.

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    Jasmina S Redzic

    Full Text Available Extracellular vesicles (EVs are key contributors to cancer where they play an integral role in cell-cell communication and transfer pro-oncogenic molecules to recipient cells thereby conferring a cancerous phenotype. Here, we purified EVs using straightforward biochemical approaches from multiple cancer cell lines and subsequently characterized these EVs via multiple biochemical and biophysical methods. In addition, we used fluorescence microscopy to directly show internalization of EVs into the recipient cells within a few minutes upon addition of EVs to recipient cells. We confirmed that the transmembrane protein EMMPRIN, postulated to be a marker of EVs, was indeed secreted from all cell lines studied here. We evaluated the response to EV stimulation in several different types of recipient cells lines and measured the ability of these purified EVs to induce secretion of several factors highly upregulated in human cancers. Our data indicate that purified EVs preferentially stimulate secretion of several proteins implicated in driving cancer in monocytic cells but only harbor limited activity in epithelial cells. Specifically, we show that EVs are potent stimulators of MMP-9, IL-6, TGF-β1 and induce the secretion of extracellular EMMPRIN, which all play a role in driving immune evasion, invasion and inflammation in the tumor microenvironment. Thus, by using a comprehensive approach that includes biochemical, biological, and spectroscopic methods, we have begun to elucidate the stimulatory roles.

  6. Dextran sulphate crowding and sodium deoxycholate lysis of primary breast fibroblast cells achieve extracellular matrix deposition and decellularization for breast cancer stem cell culture

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    Aroem Naruni

    2016-01-01

    Full Text Available AbstrakLatar belakang: Lingkungan mikro yaitu sel stromal dam matriks ekstraseluler saat ini dinyatakansebagai kontributor dalam perkembangan tumor. Beberapa penelitian telah mengembangkan matriksekstraseluler yang mendukung perkembangan sel in vitro. Matriks ekstraseluler adalah suatu komplekssusunan supramolekuler dari berbagai macam glycoprotein dan proteoglycan. Matriks ekstraselulermenyediakan integritas jaringan, bertindak sebagai scaffold alami tempat sel melekat dan berinteraksiserta berperan sebagai reservoir pertumbuhan sel. Penelitian ini bertujuan untuk mendapatkan deposisidan deselularisasi yang optimal pada matriks ekstraseluler.Metode: Dalam penelitian ini, kami mengembangkan cells crowder untuk meningkatkan deposit matriksekstraseluler dari kultur sel primer fibroblast payudara yang diperoleh dari spesimen hasil operasimammoplasty. Dextran 500 kDa ditambahkan dalam media kultur DMEM lengkap yang telah ditambahkan0.5% FBS dan 100μM L-ascorbic acid 2-phosphate. Setelah tujuh hari, sel dilisis dengan menggunakanSodium Deoxycolate (DOC.Hasil: Deposisi matriks ekstraseluler dan proses deselulerisasi dari sel primer fibroblas payudara dapatterdeteksi dengan menggunakan antibodi Rabbit anti human fibronectin yang selanjutnya ditambahkandengan anti rabbit IgG yang telah dikonjugasi dengan Alexa Fluor 488.Kesimpulan: Penambahan dextran sulfat dan prosesing lysis dengan sodium deoxycolate dapatmeningkatkan deposisi dan menghasilkan deselularisasi matriks ekstraseluler. (Health Science Journalof Indonesia 2015;6:43-7Kata kunci: matriks ekstra selular, kanker mammae, stem cell, sel fibroblast AbstractBackground: The microenvironment including stromal cells and extracellular matrix (ECM is now consideredan active contributor to tumor progression. Certain studies have developed ECM which supports a suitable cellulargrowth in vitro. The ECM is a complex supramolecular assembly of a variety of glycoproteins and proteoglycans.Extracellular

  7. Effects of transforming growth factor-beta1 on cell motility, collagen gel contraction, myofibroblastic differentiation, and extracellular matrix expression of human adipose-derived stem cell.

    Science.gov (United States)

    Kakudo, Natsuko; Kushida, Satoshi; Suzuki, Kenji; Ogura, Tsunetaka; Notodihardjo, Priscilla Valentin; Hara, Tomoya; Kusumoto, Kenji

    2012-12-01

    Human adipose-derived stem cells (ASCs) are adult pluripotent stem cells, and their usefulness in plastic surgery has garnered attention in recent years. Although, there have been expectations that ASCs might function in wound repair and regeneration, no studies to date have examined the role of ASCs in the mechanism that promotes wound-healing. Transforming growth factor-beta1 (TGF-β1) is a strong candidate cytokine for the triggering of mesenchymal stem cell migration, construction of extracellular matrices, and differentiation of ASCs into myofibroblasts. Cell proliferation, motility, and differentiation, as well as extracellular matrix production, play an important role in wound-healing. We have evaluated the capacity of ASCs to proliferate and their potential to differentiate into phenotypic myofibroblasts, as well as their cell motility and collagen gel contraction ability, when cultured with TGF-β1. Cell motility was analyzed using a wound-healing assay. ASCs that differentiated into myofibroblasts expressed the gene for alpha-smooth muscle actin, and its protein expression was detected immunohistochemically. The extracellular matrix expression in ASCs was evaluated using real-time RT-PCR. Based on the results, we conclude that human ASCs have the potential for cell motility, extracellular matrix gene expression, gel contraction, and differentiation into myofibroblasts and, therefore, may play an important role in the wound-healing process.

  8. Mesenchymal stromal cells improve human islet function through released products and extracellular matrix.

    Science.gov (United States)

    Arzouni, Ahmed A; Vargas-Seymour, Andreia; Rackham, Chloe L; Dhadda, Paramjeet; Huang, Guo-Cai; Choudhary, Pratik; Nardi, Nance; King, Aileen J F; Jones, Peter M

    2017-12-01

    The aims of the present study were (i) to determine whether the reported beneficial effects of mesenchymal stromal cells (MSCs) on mouse islet function extend to clinically relevant human tissues (islets and MSCs), enabling translation into improved protocols for clinical human islet transplantation; and (ii) to identify possible mechanisms through which human MSCs influence human islet function. Human islets were co-cultured with human adipose tissue-derived MSCs (hASCs) or pre-treated with its products - extracellular matrix (ECM) and annexin A1 (ANXA1). Mouse islets were pre-treated with mouse MSC-derived ECM. Islet insulin secretory function was assessed in vitro by radioimmunoassay. Quantitative RT-PCR was used to screen human adipMSCs for potential ligands of human islet G-protein-coupled receptors. We show that co-culture with hASCs improves human islet secretory function in vitro , as measured by glucose-stimulated insulin secretion, confirming previous reports using rodent tissues. Furthermore, we demonstrate that these beneficial effects on islet function can be partly attributed to the MSC-derived products ECM and ANXA1. Our results suggest that hASCs have the potential to improve the quality of human islets isolated for transplantation therapy of Type 1 diabetes. Furthermore, it may be possible to achieve improvements in human islet quality in a cell-free culture system by using the MSC-derived products ANXA1 and ECM. © 2017 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

  9. Morphological and ultrastructural characteristics of extracellular matrix changes in oral squamous cell carcinoma

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    Usha Agrawal

    2011-01-01

    Full Text Available Background: The biology of oral squamous cell carcinoma (OSCC, including its progression from dysplasia to carcinoma, "field effects", genetic changes in tumor associated mucosa (TAM and effect of matrix metalloproteinases in breaking down of matrix proteins to facilitate invasion, has been well documented. However, what remains to be done is to extrapolate this knowledge to improve patient care. Aim: The aim of this study was to observe the extracellular matrix (ECM changes with the routine histochemical stains available to most histopathologists. Materials and Methods: The study includes 72 cases of OSCC in which the tumor and adjacent normal appearing areas were sampled to study the ECM changes with hematoxylin and eosin (H and E and Verhoeff′s-Van Gieson elastic stain (VVG. Results: Basophilic fragmentation of collagen (H and E and clumped short elastic fibers (VVG were seen in 12 (16.7% cases. Of the remaining cases, 18 (25% had a dense lymphocytic infiltrate and had no demonstrable elastic fibers. Those cases with H and E changes were further studied and compared with normal mucosa for ultrastructural changes. The ultrastructural study demonstrated an increase in oxytalan, elaunin and elastic fibers and decrease in collagen fibers with some transformation changes associated with OSCCs and lymph node metastasis. Conclusion: Changes in transformation of collagen to elastic fibers and also the loss of both the fibers in areas of lymphocytic infiltration possibly indicate degradation of ECM fibers by factors released from the lymphocytes or tumor cells and the limiting effect on the tumor by ECM remodeling.

  10. Remembrance of Dead Cells Past: Discovering That the Extracellular Matrix Is a Cell Survival Factor

    OpenAIRE

    Schwartz, Martin A.

    2010-01-01

    In 1992, Jere Meredith and I followed up on a serendipitous observation and showed that matrix deprivation can lead to apoptosis. Our article in Molecular Biology of the Cell, together with work form Steve Frisch's lab, helped establish the paradigm that integrin signals control cell survival in a variety of systems. It has been a pleasure to watch that work take on a life of its own as other investigators have explored its role in processes such as cavitation, regression of the mammary gland...

  11. Sensitization of interferon-γ induced apoptosis in human osteosarcoma cells by extracellular S100A4

    International Nuclear Information System (INIS)

    Pedersen, Kjetil Boye; Andersen, Kristin; Fodstad, Øystein; Mælandsmo, Gunhild Mari

    2004-01-01

    S100A4 is a small Ca 2+ -binding protein of the S100 family with metastasis-promoting properties. Recently, secreted S100A4 protein has been shown to possess a number of functions, including induction of angiogenesis, stimulation of cell motility and neurite extension. Cell cultures from two human osteosarcoma cell lines, OHS and its anti-S100A4 ribozyme transfected counterpart II-11b, was treated with IFN-γ and recombinant S100A4 in order to study the sensitizing effects of extracellular S100A4 on IFN-γ mediated apoptosis. Induction of apoptosis was demonstrated by DNA fragmentation, cleavage of poly (ADP-ribose) polymerase and Lamin B. In the present work, we found that the S100A4-expressing human osteosarcoma cell line OHS was more sensitive to IFN-γ-mediated apoptosis than the II-11b cells. S100A4 protein was detected in conditioned medium from OHS cells, but not from II-11b cells, and addition of recombinant S100A4 to the cell medium sensitized II-11b cells to apoptosis induced by IFN-γ. The S100A4/IFN-γ-mediated induction of apoptosis was shown to be independent of caspase activation, but dependent on the formation of reactive oxygen species. Furthermore, addition of extracellular S100A4 was demonstrated to activate nuclear factor-κB (NF-κB). In conclusion, we have shown that S100A4 sensitizes osteosarcoma cells to IFN-γ-mediated induction of apoptosis. Additionally, extracellular S100A4 activates NF-κB, but whether these events are causally related remains unknown

  12. Extracellular sugar modifications provide instructive and cell-specific information for axon-guidance choices.

    NARCIS (Netherlands)

    Bulow, H.E.; Tjoe, N.; Townley, R.A.; Didiano, D.; Kuppevelt, A.H.M.S.M. van; Hobert, O.

    2008-01-01

    Heparan sulfates (HSs) are extraordinarily complex extracellular sugar molecules that are critical components of multiple signaling systems controlling neuronal development. The molecular complexity of HSs arises through a series of specific modifications, including sulfations of sugar residues and

  13. Cavin-1/PTRF alters prostate cancer cell-derived extracellular vesicle content and internalization to attenuate extracellular vesicle-mediated osteoclastogenesis and osteoblast proliferation

    Directory of Open Access Journals (Sweden)

    Kerry L. Inder

    2014-06-01

    Full Text Available Background: Tumour-derived extracellular vesicles (EVs play a role in tumour progression; however, the spectrum of molecular mechanisms regulating EV secretion and cargo selection remain to be fully elucidated. We have reported that cavin-1 expression in prostate cancer PC3 cells reduced the abundance of a subset of EV proteins, concomitant with reduced xenograft tumour growth and metastasis. Methods: We examined the functional outcomes and mechanisms of cavin-1 expression on PC3-derived EVs (PC3-EVs. Results: PC3-EVs were internalized by osteoclast precursor RAW264.7 cells and primary human osteoblasts (hOBs in vitro, stimulating osteoclastogenesis 37-fold and hOB proliferation 1.5-fold, respectively. Strikingly, EVs derived from cavin-1-expressing PC3 cells (cavin-1-PC3-EVs failed to induce multinucleate osteoblasts or hOB proliferation. Cavin-1 was not detected in EVs, indicating an indirect mechanism of action. EV morphology, size and quantity were also not affected by cavin-1 expression, suggesting that cavin-1 modulated EV cargo recruitment rather than release. While cavin-1-EVs had no osteoclastogenic function, they were internalized by RAW264.7 cells but at a reduced efficiency compared to control EVs. EV surface proteins are required for internalization of PC3-EVs by RAW264.7 cells, as proteinase K treatment abolished uptake of both control and cavin-1-PC3-EVs. Removal of sialic acid modifications by neuraminidase treatment increased the amount of control PC3-EVs internalized by RAW264.7 cells, without affecting cavin-1-PC3-EVs. This suggests that cavin-1 expression altered the glycosylation modifications on PC3-EV surface. Finally, cavin-1 expression did not affect EV in vivo tissue targeting as both control and cavin-1-PC3-EVs were predominantly retained in the lung and bone 24 hours after injection into mice. Discussion: Taken together, our results reveal a novel pathway for EV cargo sorting, and highlight the potential of utilizing

  14. Hypothiocyanite produced by human and rat respiratory epithelial cells inactivates extracellular H1N2 influenza A virus.

    Science.gov (United States)

    Gingerich, Aaron; Pang, Lan; Hanson, Jarod; Dlugolenski, Daniel; Streich, Rebecca; Lafontaine, Eric R; Nagy, Tamás; Tripp, Ralph A; Rada, Balázs

    2016-01-01

    Our aim was to study whether an extracellular, oxidative antimicrobial mechanism inherent to tracheal epithelial cells is capable of inactivating influenza H1N2 virus. Epithelial cells were isolated from tracheas of male Sprague-Dawley rats. Both primary human and rat tracheobronchial epithelial cells were differentiated in air-liquid interface cultures. A/swine/Illinois/02860/09 (swH1N2) influenza A virions were added to the apical side of airway cells for 1 h in the presence or absence of lactoperoxidase or thiocyanate. Characterization of rat epithelial cells (morphology, Duox expression) occurred via western blotting, PCR, hydrogen peroxide production measurement and histology. The number of viable virions was determined by plaque assays. Statistical difference of the results was analyzed by ANOVA and Tukey's test. Our data show that rat tracheobronchial epithelial cells develop a differentiated, polarized monolayer with high transepithelial electrical resistance, mucin production and expression of dual oxidases. Influenza A virions are inactivated by human and rat epithelial cells via a dual oxidase-, lactoperoxidase- and thiocyanate-dependent mechanism. Differentiated air-liquid interface cultures of rat tracheal epithelial cells provide a novel model to study airway epithelium-influenza interactions. The dual oxidase/lactoperoxidase/thiocyanate extracellular oxidative system producing hypothiocyanite is a fast and potent anti-influenza mechanism inactivating H1N2 viruses prior to infection of the epithelium.

  15. Mechanical influence of tissue culture plates and extracellular matrix on mesenchymal stem cell behavior: A topical review.

    Science.gov (United States)

    Tatullo, Marco; Marrelli, Massimo; Falisi, Giovanni; Rastelli, Claudio; Palmieri, Francesca; Gargari, Marco; Zavan, Barbara; Paduano, Francesco; Benagiano, Vincenzo

    2016-03-01

    Tissue engineering applications need a continuous development of new biomaterials able to generate an ideal cell-extracellular matrix interaction. The stem cell fate is regulated by several factors, such as growth factors or transcription factors. The most recent literature has reported several publications able to demonstrate that environmental factors also contribute to the regulation of stem cell behavior, leading to the opinion that the environment plays the major role in the cell differentiation.The interaction between mesenchymal stem cells (MSCs) and extracellular environment has been widely described, and it has a crucial role in regulating the cell phenotype. In our laboratory (Tecnologica Research Institute, Crotone, Italy), we have recently studied how several physical factors influence the distribution and the morphology of MSCs isolated from dental pulp, and how they are able to regulate stem cell differentiation. Mechanical and geometrical factors are only a small part of the environmental factors able to influence stem cell behavior, however, this influence should be properly known: in fact, this assumption must be clearly considered during those studies involving MSCs; furthermore, these interactions should be considered as an important bias that involves an high number of studies on the MSCs, since in worldwide laboratories the scientists mostly use tissue culture plates for their experiments. © The Author(s) 2015.

  16. Extracellular matrix of cultured glial cells: Selective expression of chondroitin 4-sulfate by type-2 astrocytes and their progenitors

    International Nuclear Information System (INIS)

    Gallo, V.; Bertolotto, A.

    1990-01-01

    We have studied the extracellular matrix composition of cultured glial cells by immunocytochemistry with different monoclonal and polyclonal antibodies. Double immunofluorescence experiments and metabolic labeling with [3H]glucosamine performed in different types of cerebellar and cortical cultures showed that bipotential progenitors for type-2 astrocytes and for oligodendrocytes synthesize chondroitin sulfate (CS) and deposit this proteoglycan in their extracellular matrix. The distribution of the various [3H]glucosamine-labeled glycosaminoglycans between the intracellular and the extracellular space was different. CS was present both within the cells and in the culture medium, although in different amounts. Bi-potential progenitors became also O4-positive during their development in vitro. At the stage of O4-positivity they were still stained with antibodies against CS. However, when the progenitor cells were maintained in serum-free medium and differentiated into Gal-C-positive oligodendrocytes, they became CS-negative. In the presence of fetal calf serum in the culture medium, the bipotential progenitors differentiated into GFAP-positive type-2 astrocytes. These cells still expressed CS: their Golgi area and their surface were stained with anti-CS antibodies. Staining with monoclonal antibodies specific for different types of CS (4-sulfate, 6-sulfate, and unsulfated) revealed that both bipotential progenitors and type-2 astrocytes synthesized only chondroitin 4-sulfate. Type-1 astrocytes were negative for both the polyclonal and the monoclonal anti-CS antibodies. Finally, type-2 astrocytes and their progenitors were weakly stained with anti-laminin antibodies and unstained with anti-fibronectin. Type-1 astrocytes were positive for both anti-laminin and anti-fibronectin antibodies and appeared to secrete fibronectin in the extracellular space

  17. CD73 Protein as a Source of Extracellular Precursors for Sustained NAD+ Biosynthesis in FK866-treated Tumor Cells*

    Science.gov (United States)

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

    2013-01-01

    NAD+ is mainly synthesized in human cells via the “salvage” pathways starting from nicotinamide, nicotinic acid, or nicotinamide riboside (NR). The inhibition with FK866 of the enzyme nicotinamide phosphoribosyltransferase (NAMPT), catalyzing the first reaction in the “salvage” pathway from nicotinamide, showed potent antitumor activity in several preclinical models of solid and hematologic cancers. In the clinical studies performed with FK866, however, no tumor remission was observed. Here we demonstrate that low micromolar concentrations of extracellular NAD+ or NAD+ precursors, nicotinamide mononucleotide (NMN) and NR, can reverse the FK866-induced cell death, this representing a plausible explanation for the failure of NAMPT inhibition as an anti-cancer therapy. NMN is a substrate of both ectoenzymes CD38 and CD73, with generation of NAM and NR, respectively. In this study, we investigated the roles of CD38 and CD73 in providing ectocellular NAD+ precursors for NAD+ biosynthesis and in modulating cell susceptibility to FK866. By specifically silencing or overexpressing CD38 and CD73, we demonstrated that endogenous CD73 enables, whereas CD38 impairs, the conversion of extracellular NMN to NR as a precursor for intracellular NAD+ biosynthesis in human cells. Moreover, cell viability in FK866-treated cells supplemented with extracellular NMN was strongly reduced in tumor cells, upon pharmacological inhibition or specific down-regulation of CD73. Thus, our study suggests that genetic or pharmacologic interventions interfering with CD73 activity may prove useful to increase cancer cell sensitivity to NAMPT inhibitors. PMID:23880765

  18. Schwann Cells Metabolize Extracellular 2′,3′-cAMP to 2′-AMP

    Science.gov (United States)

    Verrier, Jonathan D.; Kochanek, Patrick M.

    2015-01-01

    The 3′,5′-cAMP–adenosine pathway (3′,5′-cAMP→5′-AMP→adenosine) and the 2′,3′-cAMP–adenosine pathway (2′,3′-cAMP→2′-AMP/3′-AMP→adenosine) are active in the brain. Oligodendrocytes participate in the brain 2′,3′-cAMP–adenosine pathway via their robust expression of 2′,3′-cyclic nucleotide 3′-phosphodiesterase (CNPase; converts 2′,3′-cAMP to 2′-AMP). Because Schwann cells also express CNPase, it is conceivable that the 2′,3′-cAMP–adenosine pathway exists in the peripheral nervous system. To test this and to compare the 2′,3′-cAMP–adenosine pathway to the 3′,5′-cAMP–adenosine pathway in Schwann cells, we examined the metabolism of 2′,3′-cAMP, 2′-AMP, 3′-AMP, 3′,5′-cAMP, and 5′-AMP in primary rat Schwann cells in culture. Addition of 2′,3′-cAMP (3, 10, and 30 µM) to Schwann cells increased levels of 2′-AMP in the medium from 0.006 ± 0.002 to 21 ± 2, 70 ± 3, and 187 ± 10 nM/µg protein, respectively; in contrast, Schwann cells had little ability to convert 2′,3′-cAMP to 3′-AMP or 3′,5′-cAMP to either 3′-AMP or 5′-AMP. Although Schwann cells slightly converted 2′,3′-cAMP and 2′-AMP to adenosine, they did so at very modest rates (e.g., 5- and 3-fold, respectively, more slowly compared with our previously reported studies in oligodendrocytes). Using transected myelinated rat sciatic nerves in culture medium, we observed a time-related increase in endogenous intracellular 2′,3′-cAMP and extracellular 2′-AMP. These findings indicate that Schwann cells do not have a robust 3′,5′-cAMP–adenosine pathway but do have a 2′,3′-cAMP–adenosine pathway; however, because the pathway mostly involves 2′-AMP formation rather than 3′-AMP, and because the conversion of 2′-AMP to adenosine is slow, metabolism of 2′,3′-cAMP mostly results in the accumulation of 2′-AMP. Accumulation of 2′-AMP in peripheral nerves postinjury could have

  19. A novel functional site of extracellular matrix metalloproteinase inducer (EMMPRIN) that limits the migration of human uterine cervical carcinoma cells.

    Science.gov (United States)

    Sato, Takashi; Watanabe, Mami; Hashimoto, Kei; Ota, Tomoko; Akimoto, Noriko; Imada, Keisuke; Nomizu, Motoyoshi; Ito, Akira

    2012-01-01

    EMMPRIN (extracellular matrix metalloproteinase inducer)/CD147, a membrane-bound glycoprotein with two extracellular loop domains (termed loops I and II), progresses tumor invasion and metastasis by increasing the production of matrix metalloproteinase (MMP) in peritumoral stoma cells. EMMPRIN has also been associated with the control of migration activity in some tumor cells, but little is known about how EMMPRIN regulates tumor cell migration. In the present study, EMMPRIN siRNA suppressed the gene expression and production of EMMPRIN in human uterine cervical carcinoma SKG-II cells. An in vitro scratch wound assay showed enhancement of migration of EMMPRIN-knockdown SKG-II cells. In addition, the SKG-II cell migration was augmented by adding an E. coli-expressed human EMMPRIN mutant with two extracellular loop domains (eEMP-I/II), which bound to the cell surface of SKG-II cells. However, eEMP-I/II suppressed the native EMMPRIN-mediated augmentation of proMMP-1/procollagenase-1 production in a co-culture of the SKG-II cells and human uterine cervical fibroblasts, indicating that the augmentation of SKG-II cell migration resulted from the interference of native EMMPRIN functions by eEMP-I/II on the cell surface. Furthermore, a systematic peptide screening method using nine synthetic EMMPRIN peptides coding the loop I and II domains (termed EM1-9) revealed that EM9 (170HIENLNMEADPGQYR184) facilitated SKG-II cell migration. Moreover, SKG-II cell migration was enhanced by administration of an antibody against EM9, but not EM1 which is a crucial site for the MMP inducible activity of EMMPRIN. Therefore, these results provide novel evidence that EMMPRIN on the cell surface limits the cell migration of human uterine cervical carcinoma cells through 170HIENLNMEADPGQYR184 in the loop II domain. Finally, these results should provide an increased understanding of the functions of EMMPRIN in malignant cervical carcinoma cells, and could contribute to the development of

  20. Deposition of tropoelastin into the extracellular matrix requires a competent elastic fiber scaffold but not live cells.

    Science.gov (United States)

    Kozel, Beth A; Ciliberto, Christopher H; Mecham, Robert P

    2004-04-01

    The initial steps of elastic fiber assembly were investigated using an in vitro assembly model in which purified recombinant tropoelastin (rbTE) was added to cultures of live or dead cells. The ability of tropoelastin to associate with preexisting elastic fibers or microfibrils in the extracellular matrix was then assessed by immunofluorescence microscopy using species-specific tropoelastin antibodies. Results show that rbTE can associate with elastic fiber components in the absence of live cells through a process that does not depend on crosslink formation. Time course studies show a transformation of the deposited protein from an initial globular appearance early in culture to a more fibrous structure as the matrix matures. Deposition required the C-terminal region of tropoelastin and correlated with the presence of preexisting elastic fibers or microfibrils. Association of exogenously added tropoelastin to the cellular extracellular matrix was inhibited by the addition of heparan sulfate but not chondroitin sulfate sugars. Together, these results suggest that the matrix elaborated by the cell is sufficient for the initial deposition of tropoelastin in the extracellular space and that elastin assembly may be influenced by the composition of sulfated proteoglycans in the matrix.

  1. What is the functional background of filigree extracellular matrix and cell-cell connections at the interface of the renal stem/progenitor cell niche?

    Directory of Open Access Journals (Sweden)

    Will W. Minuth

    2015-12-01

    Full Text Available Development of a nephron is induced by a reciprocal exchange of morphogenetic proteins between epithelial and mesenchymal cells within the renal stem/progenitor cell niche. For sustaining concentration of diffusing proteins high, it is believed that an intimate contact exists between involved cells. However, actual morphological data show that both types of stem/progenitor cell bodies are separated by an interface. To analyze details of this arrangement, neonatal rabbit kidneys were fixed in traditional glutaraldehyde (GA solution for transmission electron microscopy. For an enhanced contrast fixation of samples was performed in GA solution including either cupromeronic blue, ruthenium red or tannic acid. To record always the same perspective, embedded blocks of parenchyma were cut in orientated vertical and transverse planes to the lumen of lining collecting duct tubules. Screening of samples fixed by GA solution demonstrates a constant separation of stem/progenitor cell bodies by an unobstrusively looking interface. In contrast, improved fixation of specimens in GA solution including cupromeronic blue, ruthenium red or tannic acid unveils between them earlier not visible filigree extracellular matrix. Further projections of mesenchymal cells covered by this matrix cross the interface to contact epithelial cells. The end of a projection does not dangle but is mounted by a special plug connection. At this site the plasma membranes of mesenchymal and epithelial cells are connected via tunneling nanotubes. Regarding this unique arrangement the principal question is to what extent illustrated extracellular matrix and cell-cell connections are involved in the exchange of morphogenetic proteins during induction of a nephron. Proceedings of the 2nd International Course on Perinatal Pathology (part of the 11th International Workshop on Neonatology · October 26th-31st, 2015 · Cagliari (Italy · October 31st, 2015 · Stem cells: present and future

  2. Extracellular concentration of homocysteine in human cell lines is influenced by specific inhibitors of cyst(e)ine transport.

    Science.gov (United States)

    Hultberg, Björn

    2004-04-01

    Despite the growing evidence that plasma homocysteine is a cardiovascular risk factor, the mechanism behind the vascular injuries is still unknown. Studies of the cellular uptake systems for homocysteine are scarce, but membrane transporters of cyst(e)ine seem to be involved. In the present study the cellular uptake of extracellular homocysteine in HeLa and hepatoma cell lines is investigated by using several different transport inhibitors for cellular uptake of cyst(e)ine. It is shown that systems A and Xc- are the main transport systems for homocysteine uptake in HeLa cells. It is also confirmed that the magnitude of homocysteine uptake in hepatoma cells is lower than in HeLa cells. However, in the presence of high amounts of extracellular homocysteine both cell types exhibited a high elimination of homocysteine, which was inhibited by the presence of inhibitors of systems A or Xc-. It is possible that there is normally a high turnover of homocysteine in cell cultures, which is not detected by occasional determinations of homocysteine concentrations. The complex pattern of homocysteine production, release, uptake and distribution between different cells in the body is important to examine further in order to possibly be able to modulate the elimination of homocysteine from circulation and thereby lower the risk of cardiovascular disease.

  3. Atypical protein kinase C activity is required for extracellular matrix degradation and invasion by Src-transformed cells.

    Science.gov (United States)

    Rodriguez, Elena M; Dunham, Elizabeth E; Martin, G Steven

    2009-10-01

    Atypical protein kinase C (aPKC) isoforms have been shown to mediate Src-dependent signaling in response to growth factor stimulation. To determine if aPKC activity contributes to the transformed phenotype of cells expressing oncogenic Src, we have examined the activity and function of aPKCs in 3T3 cells expressing viral Src (v-Src). aPKC activity and tyrosine phosphorylation were found to be elevated in some but not all clones of mouse fibroblasts expressing v-Src. aPKC activity was inhibited either by addition of a membrane-permeable pseudosubstrate, by expression of a dominant-negative aPKC, or by RNAi-mediated knockdown of specific aPKC isoforms. aPKC activity contributes to morphological transformation and stress fiber disruption, and is required for migration of Src-transformed cells and for their ability to polarize at the edge of a monolayer. The lambda isoform of aPKC is specifically required for invasion through extracellular matrix in Boyden chamber assays and for degradation of the extracellular matrix in in situ zymography assays. Tyrosine phosphorylation of aPKClambda is required for its ability to promote cell invasion. The defect in invasion upon aPKC inhibition appears to result from a defect in the assembly and/or function of podosomes, invasive adhesions on the ventral surface of the cell that are sites of protease secretion. aPKC was also found to localize to podosomes of v-Src transformed cells, suggesting a direct role for aPKC in podosome assembly and/or function. We conclude that basal or elevated aPKC activity is required for the ability of Src-transformed cells to degrade and invade the extracellular matrix. Copyright 2009 Wiley-Liss, Inc.

  4. * Tissue-Specific Extracellular Matrix Enhances Skeletal Muscle Precursor Cell Expansion and Differentiation for Potential Application in Cell Therapy.

    Science.gov (United States)

    Zhang, Deying; Zhang, Yong; Zhang, Yuanyuan; Yi, Hualin; Wang, Zhan; Wu, Rongpei; He, Dawei; Wei, Guanghui; Wei, Shicheng; Hu, Yun; Deng, Junhong; Criswell, Tracy; Yoo, James; Zhou, Yu; Atala, Anthony

    2017-08-01

    Skeletal muscle precursor cells (MPCs) are considered a key candidate for cell therapy in the treatment of skeletal muscle dysfunction due to injury, disease, or age. However, expansion of a sufficient number of functional skeletal muscle cells in vitro from a small tissue biopsy has been challenging due to changes in phenotypic expression of these cells under traditional culture conditions. Thus, the aim of the study was to develop a better culture system for the expansion and myo-differentiation of MPCs that could further be used for therapy. For this purpose, we developed an ideal method of tissue decellularization and compared the ability of different matrices to support MPC growth and differentiation. Porcine-derived skeletal muscle and liver and kidney extracellular matrix (ECM) were generated by decellularization methods consisting of distilled water, 0.2 mg/mL DNase, or 5% fetal bovine serum. Acellular matrices were further homogenized, dissolved, and combined with a hyaluronic acid-based hydrogel decorated with heparin (ECM-HA-HP). The cell proliferation and myogenic differentiation capacity of human MPCs were assessed when grown on gel alone, ECM, or each ECM-HA-HP substrate. Human MPC proliferation was significantly enhanced when cultured on the ECM-HA-HP substrates compared to the other substrates tested, with the greatest proliferation on the muscle ECM-HA-HP (mECM-HA-HP) substrate. The number of differentiated myotubes was significantly increased on the mECM-HA-HP substrate compared to the other gel-ECM substrates, as well as the numbers of MPCs expressing specific myogenic cell markers (i.e., myosin, desmin, myoD, and myf5). In conclusion, skeletal mECM-HA-HP as a culture substrate provided an optimal culture microenvironment potentially due to its similarity to the in vivo environment. These data suggest a potential use of skeletal muscle-derived ECM gel for the expansion and differentiation of human MPCs for cell-based therapy for skeletal muscle

  5. Maintenance of the Extracellular Matrix in Rat Anterior Pituitary Gland: Identification of Cells Expressing Tissue Inhibitors of Metalloproteinases.

    Science.gov (United States)

    Azuma, Morio; Tofrizal, Alimuddin; Maliza, Rita; Batchuluun, Khongorzul; Ramadhani, Dini; Syaidah, Rahimi; Tsukada, Takehiro; Fujiwara, Ken; Kikuchi, Motoshi; Horiguchi, Kotaro; Yashiro, Takashi

    2015-12-25

    The extracellular matrix (ECM) is important in creating cellular environments in tissues. Recent studies have demonstrated that ECM components are localized in anterior pituitary cells and affect cell activity. Thus, clarifying the mechanism responsible for ECM maintenance would improve understanding of gland function. Tissue inhibitors of metalloproteinases (TIMPs) are endogenous inhibitors of matrix metalloproteinases and participate in ECM degradation. In this study, we investigated whether cells expressing TIMPs are present in rat anterior pituitary gland. Reverse transcription polymerase chain reaction was used to analyze expression of the TIMP family (TIMP1-4), and cells producing TIMPs in the gland were identified by using in situ hybridization. Expression of TIMP1, TIMP2, and TIMP3 mRNAs was detected, and the TIMP-expressing cells were located in the gland. The TIMP-expressing cells were also investigated by means of double-staining with in situ hybridization and immunohistochemical techniques. Double-staining revealed that TIMP1 mRNA was expressed in folliculostellate cells. TIMP2 mRNA was detected in folliculostellate cells, prolactin cells, and thyroid-stimulating hormone cells. TIMP3 mRNA was identified in endothelial cells, pericytes, novel desmin-immunopositive perivascular cells, and folliculostellate cells. These findings indicate that TIMP1-, TIMP2-, and TIMP3-expressing cells are present in rat anterior pituitary gland and that they are involved in maintaining ECM components.

  6. Maintenance of the Extracellular Matrix in Rat Anterior Pituitary Gland: Identification of Cells Expressing Tissue Inhibitors of Metalloproteinases

    International Nuclear Information System (INIS)

    Azuma, Morio; Tofrizal, Alimuddin; Maliza, Rita; Batchuluun, Khongorzul; Ramadhani, Dini; Syaidah, Rahimi; Tsukada, Takehiro; Fujiwara, Ken; Kikuchi, Motoshi; Horiguchi, Kotaro; Yashiro, Takashi

    2015-01-01

    The extracellular matrix (ECM) is important in creating cellular environments in tissues. Recent studies have demonstrated that ECM components are localized in anterior pituitary cells and affect cell activity. Thus, clarifying the mechanism responsible for ECM maintenance would improve understanding of gland function. Tissue inhibitors of metalloproteinases (TIMPs) are endogenous inhibitors of matrix metalloproteinases and participate in ECM degradation. In this study, we investigated whether cells expressing TIMPs are present in rat anterior pituitary gland. Reverse transcription polymerase chain reaction was used to analyze expression of the TIMP family (TIMP1-4), and cells producing TIMPs in the gland were identified by using in situ hybridization. Expression of TIMP1, TIMP2, and TIMP3 mRNAs was detected, and the TIMP-expressing cells were located in the gland. The TIMP-expressing cells were also investigated by means of double-staining with in situ hybridization and immunohistochemical techniques. Double-staining revealed that TIMP1 mRNA was expressed in folliculostellate cells. TIMP2 mRNA was detected in folliculostellate cells, prolactin cells, and thyroid-stimulating hormone cells. TIMP3 mRNA was identified in endothelial cells, pericytes, novel desmin-immunopositive perivascular cells, and folliculostellate cells. These findings indicate that TIMP1-, TIMP2-, and TIMP3-expressing cells are present in rat anterior pituitary gland and that they are involved in maintaining ECM components

  7. Ouabain enhancement of compound 48/80 induced histamine secretion from rat peritoneal mast cells: dependence on extracellular sodium

    DEFF Research Database (Denmark)

    Knudsen, T; Bertelsen, Niels Haldor; Johansen, Torben

    1992-01-01

    Purified populations of rat peritoneal mast cells were used to study the effect of ouabain on compound 48/80-induced histamine secretion and on 86Rb+ uptake. 86Rb+ was used as a tracer for extracellular K+. The calculated value of the ouabain-sensitive uptake of K+ and 86Rb+ was considered...... on the secretion occurs in the presence of sodium but not when sodium was replaced by lithium. Preservation by ouabain of a high intracellular sodium content in sodium-loaded cells was associated with preservation of the secretory response in a calcium-free medium. In the presence of lanthanum in a calcium...

  8. T Follicular Helper Cells Promote a Beneficial Gut Ecosystem for Host Metabolic Homeostasis by Sensing Microbiota-Derived Extracellular ATP.

    Science.gov (United States)

    Perruzza, Lisa; Gargari, Giorgio; Proietti, Michele; Fosso, Bruno; D'Erchia, Anna Maria; Faliti, Caterina Elisa; Rezzonico-Jost, Tanja; Scribano, Daniela; Mauri, Laura; Colombo, Diego; Pellegrini, Giovanni; Moregola, Annalisa; Mooser, Catherine; Pesole, Graziano; Nicoletti, Mauro; Norata, Giuseppe Danilo; Geuking, Markus B; McCoy, Kathy D; Guglielmetti, Simone; Grassi, Fabio

    2017-03-14

    The ATP-gated ionotropic P2X7 receptor regulates T follicular helper (Tfh) cell abundance in the Peyer's patches (PPs) of the small intestine; deletion of P2rx7, encoding for P2X7, in Tfh cells results in enhanced IgA secretion and binding to commensal bacteria. Here, we show that Tfh cell activity is important for generating a diverse bacterial community in the gut and that sensing of microbiota-derived extracellular ATP via P2X7 promotes the generation of a proficient gut ecosystem for metabolic homeostasis. The results of this study indicate that Tfh cells play a role in host-microbiota mutualism beyond protecting the intestinal mucosa by induction of affinity-matured IgA and suggest that extracellular ATP constitutes an inter-kingdom signaling molecule important for selecting a beneficial microbial community for the host via P2X7-mediated regulation of B cell help. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  9. T Follicular Helper Cells Promote a Beneficial Gut Ecosystem for Host Metabolic Homeostasis by Sensing Microbiota-Derived Extracellular ATP

    Directory of Open Access Journals (Sweden)

    Lisa Perruzza

    2017-03-01

    Full Text Available The ATP-gated ionotropic P2X7 receptor regulates T follicular helper (Tfh cell abundance in the Peyer’s patches (PPs of the small intestine; deletion of P2rx7, encoding for P2X7, in Tfh cells results in enhanced IgA secretion and binding to commensal bacteria. Here, we show that Tfh cell activity is important for generating a diverse bacterial community in the gut and that sensing of microbiota-derived extracellular ATP via P2X7 promotes the generation of a proficient gut ecosystem for metabolic homeostasis. The results of this study indicate that Tfh cells play a role in host-microbiota mutualism beyond protecting the intestinal mucosa by induction of affinity-matured IgA and suggest that extracellular ATP constitutes an inter-kingdom signaling molecule important for selecting a beneficial microbial community for the host via P2X7-mediated regulation of B cell help.

  10. Extracellular biosynthesis of silver nanoparticles using the cell-free filtrate of nematophagous fungus Duddingtonia flagrans

    Directory of Open Access Journals (Sweden)

    Costa Silva LP

    2017-08-01

    Full Text Available Laryssa Pinheiro Costa Silva,1 Jairo Pinto Oliveira,2 Wanderson Juvencio Keijok,2 André Romero da Silva,3 Anderson Rocha Aguiar,1 Marco Cesar Cunegundes Guimarães,2 Carolina Magri Ferraz,1 Jackson Victor Araújo,4 Fernando Luiz Tobias,5 Fábio Ribeiro Braga1 1Department of Parasitology, University Vila Velha, Vila Velha, Espírito Santo, Brazil; 2Morphology Department, Federal University of Espírito Santo, Vitória, Espírito Santo, Brazil; 3Federal Institute of Education, Science and Technology of Espírito Santo, Aracruz, Espírito Santo, Brazil; 4Department of Veterinary Medicine, Federal University of Viçosa, Viçosa, Minas Gerais, Brazil; 5Department of Microbiology, University Vila Velha, Vila Velha, Espírito Santo, Brazil Abstract: The biosynthesis of metallic nanoparticles (NPs using biological systems such as fungi has evolved to become an important area of nanobiotechnology. Herein, we report for the first time the extracellular synthesis of highly stable silver NPs (AgNPs using the nematophagous fungus Duddingtonia flagrans (AC001. The fungal cell-free filtrate was analyzed by the Bradford method and 3,5-dinitrosalicylic acid assay and used to synthesize the AgNPs in the presence of a 1 mM AgNO3 solution. They have been characterized by UV–Vis spectroscopy, X-ray diffraction, transmission electron microscopy, dynamic light scattering, Zeta potential measurements, Fourier-transform infrared, and Raman spectroscopes. UV–Vis spectroscopy confirmed bioreduction, while X-ray diffractometry established the crystalline nature of the AgNPs. Dynamic light scattering and transmission electron microscopy images showed approximately 11, 38 nm monodisperse and quasispherical AgNPs. Zeta potential analysis was able to show a considerable stability of AgNPs. The N–H stretches in Fourier-transform infrared spectroscopy indicate the presence of protein molecules. The Raman bands suggest that chitinase was involved in the growth and

  11. Salivary extracellular vesicle-associated miRNAs as potential biomarkers in oral squamous cell carcinoma.

    Science.gov (United States)

    Gai, Chiara; Camussi, Francesco; Broccoletti, Roberto; Gambino, Alessio; Cabras, Marco; Molinaro, Luca; Carossa, Stefano; Camussi, Giovanni; Arduino, Paolo G

    2018-04-18

    Several studies in the past have investigated the expression of micro RNAs (miRNAs) in saliva as potential biomarkers. Since miRNAs associated with extracellular vesicles (EVs) are known to be protected from enzymatic degradation, we evaluated whether salivary EVs from patients with oral squamous cell carcinoma (OSCC) were enriched with specific subsets of miRNAs. OSCC patients and controls were matched with regards to age, gender and risk factors. Total RNA was extracted from salivary EVs and the differential expression of miRNAs was evaluated by qRT-PCR array and qRT-PCR. The discrimination power of up-regulated miRNAs as biomarkers in OSCC patients versus controls was evaluated by the Receiver Operating Characteristic (ROC) curves. A preliminary qRT-PCR array was performed on samples from 5 OSCC patients and 5 healthy controls whereby a subset of miRNAs were identified that were differentially expressed. On the basis of these results, a cohort of additional 16 patients and 6 controls were analyzed to further confirm the miRNAs that were up-regulated or selectively expressed in the previous pilot study. The following miRNAs: miR-302b-3p and miR-517b-3p were expressed only in EVs from OSCC patients and miR-512-3p and miR-412-3p were up-regulated in salivary EVs from OSCC patients compared to controls with the ROC curve showing a good discrimination power for OSCC diagnosis. The Kyoto Encyclopedia of Gene and Genomes (KEGG) pathway analysis suggested the possible involvement of the miRNAs identified in pathways activated in OSCC. In this work, we suggest that salivary EVs isolated by a simple charge-based precipitation technique can be exploited as a non-invasive source of miRNAs for OSCC diagnosis. Moreover, we have identified a subset of miRNAs selectively enriched in EVs of OSCC patients that could be potential biomarkers.

  12. Enhanced transfection efficiency of human embryonic stem cells by the incorporation of DNA liposomes in extracellular matrix.

    Science.gov (United States)

    Villa-Diaz, Luis G; Garcia-Perez, Jose L; Krebsbach, Paul H

    2010-12-01

    Because human embryonic stem (hES) cells can differentiate into virtually any cell type in the human body, these cells hold promise for regenerative medicine. The genetic manipulation of hES cells will enhance our understanding of genes involved in early development and will accelerate their potential use and application for regenerative medicine. The objective of this study was to increase the transfection efficiency of plasmid DNA into hES cells by modifying a standard reverse transfection (RT) protocol of lipofection. We hypothesized that immobilization of plasmid DNA in extracellular matrix would be a more efficient method for plasmid transfer due to the affinity of hES cells for substrates such as Matrigel and to the prolonged exposure of cells to plasmid DNA. Our results demonstrate that this modification doubled the transfection efficiency of hES cells and the generation of clonal cell lines containing a piece of foreign DNA stably inserted in their genomes compared to results obtained with standard forward transfection. In addition, treatment with dimethyl sulfoxide further increased the transfection efficiency of hES cells. In conclusion, modifications to the RT protocol of lipofection result in a significant and robust increase in the transfection efficiency of hES cells.

  13. VANGL2 interacts with integrin αv to regulate matrix metalloproteinase activity and cell adhesion to the extracellular matrix.

    Science.gov (United States)

    Jessen, Tammy N; Jessen, Jason R

    2017-12-15

    Planar cell polarity (PCP) proteins are implicated in a variety of morphogenetic processes including embryonic cell migration and potentially cancer progression. During zebrafish gastrulation, the transmembrane protein Vang-like 2 (VANGL2) is required for PCP and directed cell migration. These cell behaviors occur in the context of a fibrillar extracellular matrix (ECM). While it is thought that interactions with the ECM regulate cell migration, it is unclear how PCP proteins such as VANGL2 influence these events. Using an in vitro cell culture model system, we previously showed that human VANGL2 negatively regulates membrane type-1 matrix metalloproteinase (MMP14) and activation of secreted matrix metalloproteinase 2 (MMP2). Here, we investigated the functional relationship between VANGL2, integrin αvβ3, and MMP2 activation. We provide evidence that VANGL2 regulates cell surface integrin αvβ3 expression and adhesion to fibronectin, laminin, and vitronectin. Inhibition of MMP14/MMP2 activity suppressed the cell adhesion defect in VANGL2 knockdown cells. Furthermore, our data show that MMP14 and integrin αv are required for increased proteolysis by VANGL2 knockdown cells. Lastly, we have identified integrin αvβ3 as a novel VANGL2 binding partner. Together, these findings begin to dissect the molecular underpinnings of how VANGL2 regulates MMP activity and cell adhesion to the ECM. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  14. Sox9 is required for precursor cell expansion and extracellular matrix organization during mouse heart valve development.

    Science.gov (United States)

    Lincoln, Joy; Kist, Ralf; Scherer, Gerd; Yutzey, Katherine E

    2007-05-01

    Heart valve structures derived from mesenchymal cells of the endocardial cushions (ECs) are composed of highly organized cell lineages and extracellular matrix. Sox9 is a transcription factor required for both early and late stages of cartilage formation that is also expressed in the developing valves of the heart. The requirements for Sox9 function during valvulogenesis and adult valve homeostasis in mice were examined by conditional inactivation of Sox9 using Tie2-cre and Col2a1-cre transgenes. Sox9(flox/flox);Tie2-cre mice die before E14.5 with hypoplastic ECs, reduced cell proliferation and altered extracellular matrix protein (ECM) deposition. Sox9(flox/flox);Col2a1-cre mice die at birth with thickened heart valve leaflets, reduced expression of cartilage-associated proteins and abnormal ECM patterning. Thickened valve leaflets and calcium deposits, characteristic of valve disease, are observed in heterozygous adult Sox9(flox/+);Col2a1-cre mice. Therefore, Sox9 is required early in valve development for expansion of the precursor cell population and later is required for normal expression and distribution of valvular ECM proteins. These data indicate that Sox9 is required for early and late stages of valvulogenesis and identify a potential role for Sox9 in valve disease mechanisms.

  15. Properties of internalization factors contributing to the uptake of extracellular DNA into tumor-initiating stem cells of mouse Krebs-2 cell line.

    Science.gov (United States)

    Dolgova, Evgeniya V; Potter, Ekaterina A; Proskurina, Anastasiya S; Minkevich, Alexandra M; Chernych, Elena R; Ostanin, Alexandr A; Efremov, Yaroslav R; Bayborodin, Sergey I; Nikolin, Valeriy P; Popova, Nelly A; Kolchanov, Nikolay A; Bogachev, Sergey S

    2016-05-25

    Previously, we demonstrated that poorly differentiated cells of various origins, including tumor-initiating stem cells present in the ascites form of mouse cancer cell line Krebs-2, are capable of naturally internalizing both linear double-stranded DNA and circular plasmid DNA. The method of co-incubating Krebs-2 cells with extracellular plasmid DNA (pUC19) or TAMRA-5'-dUTP-labeled polymerase chain reaction (PCR) product was used. It was found that internalized plasmid DNA isolated from Krebs-2 can be transformed into competent Escherichia coli cells. Thus, the internalization processes taking place in the Krebs-2 cell subpopulation have been analyzed and compared, as assayed by E. coli colony formation assay (plasmid DNA) and cytofluorescence (TAMRA-DNA). We showed that extracellular DNA both in the form of plasmid DNA and a PCR product is internalized by the same subpopulation of Krebs-2 cells. We found that the saturation threshold for Krebs-2 ascites cells is 0.5 μg DNA/10(6) cells. Supercoiled plasmid DNA, human high-molecular weight DNA, and 500 bp PCR fragments are internalized into the Krebs-2 tumor-initiating stem cells via distinct, non-competing internalization pathways. Under our experimental conditions, each cell may harbor 340-2600 copies of intact plasmid material, or up to 3.097 ± 0.044×10(6) plasmid copies (intact or not), as detected by quantitative PCR. The internalization dynamics of extracellular DNA, copy number of the plasmids taken up by the cells, and competition between different types of double-stranded DNA upon internalization into tumor-initiating stem cells of mouse ascites Krebs-2 have been comprehensively analyzed. Investigation of the extracellular DNA internalization into tumor-initiating stem cells is an important part of understanding their properties and possible destruction mechanisms. For example, a TAMRA-labeled DNA probe may serve as an instrument to develop a target for the therapy of cancer, aiming at elimination of

  16. Interaction of Munc18c and syntaxin4 facilitates invadopodium formation and extracellular matrix invasion of tumor cells.

    Science.gov (United States)

    Brasher, Megan I; Martynowicz, David M; Grafinger, Olivia R; Hucik, Andrea; Shanks-Skinner, Emma; Uniacke, James; Coppolino, Marc G

    2017-09-29

    Tumor cell invasion involves targeted localization of proteins required for interactions with the extracellular matrix and for proteolysis. The localization of many proteins during these cell-extracellular matrix interactions relies on membrane trafficking mediated in part by SNAREs. The SNARE protein syntaxin4 (Stx4) is involved in the formation of invasive structures called invadopodia; however, it is unclear how Stx4 function is regulated during tumor cell invasion. Munc18c is known to regulate Stx4 activity, and here we show that Munc18c is required for Stx4-mediated invadopodium formation and cell invasion. Biochemical and microscopic analyses revealed a physical association between Munc18c and Stx4, which was enhanced during invadopodium formation, and that a reduction in Munc18c expression decreases invadopodium formation. We also found that an N-terminal Stx4-derived peptide associates with Munc18c and inhibits endogenous interactions of Stx4 with synaptosome-associated protein 23 (SNAP23) and vesicle-associated membrane protein 2 (VAMP2). Furthermore, expression of the Stx4 N-terminal peptide decreased invadopodium formation and cell invasion in vitro Of note, cells expressing the Stx4 N-terminal peptide exhibited impaired trafficking of membrane type 1 matrix metalloproteinase (MT1-MMP) and EGF receptor (EGFR) to the cell surface during invadopodium formation. Our findings implicate Munc18c as a regulator of Stx4-mediated trafficking of MT1-MMP and EGFR, advancing our understanding of the role of SNARE function in the localization of proteins that drive tumor cell invasion. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  17. Effect of apoptosis and response of extracellular matrix proteins after chemotherapy application on human breast cancer cell spheroids.

    Science.gov (United States)

    Oktem, G; Vatansever, S; Ayla, S; Uysal, A; Aktas, S; Karabulut, B; Bilir, A

    2006-02-01

    Multicellular tumor spheroid (MTS) represents a three-dimensional structural form of tumors in laboratory conditions, and it has the characteristics of avascular micrometastases or intervascular spaces of big tumors. Recent studies indicate that extracellular matrix (ECM) proteins play a critical role in tumor metastasis, therefore normal and cancer cells require an ECM for survival, proliferation and differentiation. Doxorubicin and Docetaxel are widely used in the therapy of breast cancer, as well as in in vivo and in vitro studies. In this study, we examined the effect of apoptosis and proliferation of cells on the human breast cancer cell line, MCF-7, by using p53, bcl-2 and Ki67 gene expression, and the tendency to metastasis with extracellular matrix proteins, laminin and type IV collagen after chemotherapy in the spheroid model. The apoptotic cell death in situ was detected by TUNEL method. TUNEL-positive cells and positive immunoreactivities of laminin, type IV collagen, p53 and, bcl-2 were detected in the control group. There was no laminin and type IV collagen immunoreactivities in spheroids of drug groups. While TUNEL-positive cells and p53 immunoreactivity were detected in Docetaxel, Doxorubicin and Docetaxel/Doxorubicin groups, p53 immunoreactivity was not observed in the Docetaxel group. There was no bcl-2 immunoreactivity in either drug group. In addition, we did not detect Ki67 immunoreactivity in both control and drug treatment groups. However, the absence of Ki67 protein in MCF-7 breast multicellular tumor spheroids is possibly related to the cells in G0 or S phase. These chemotherapeutic agents may affect the presence of ECM proteins in this in vitro model of micrometastasis of spheroids. These findings suggest that the possible mechanism of cell death in Doxorubicin and Docetaxel/Doxorubicin treatment groups is related to apoptosis through the p53 pathway. However, we considered the possibility that there is another control mechanism for the

  18. The effect of extracellular alkalinization on lactate metabolism of breast cancer stem cells: Overview of LDH-A, LDH-B, MCT1 and MCT4 gene expression

    Science.gov (United States)

    Neolaka, G. M. G.; Yustisia, I.; Sadikin, M.; Wanandi, S. I.

    2017-08-01

    Changes in the metabolic status of cancer cells are presumed to be correlated with the adjustment of these cells to extracellular changes. Cell glycolysis increases the production of intracellular lactate catalyzed by the lactate dehydrogenases, both LDH-A and LDH-B. An increase in intracellular lactate can affect extracellular pH balance through monocarboxylate transporters, particularly MCT1 and MCT4. This study aimed to analyze the effects of extracellular alkalinization on the lactate metabolism of human breast cancer stem cells (BCSCs). In this study, human primary BCSCs (CD24-/CD44+ cells) were treated with 100 mM sodium bicarbonate for 0.5, 24, and 48 h in DMEM F12/HEPES. After incubation, extracellular pH was measured and cells were harvested to extract the total RNA and protein. The expression of LDH-A, LDH-B, MCT1, and MCT4 mRNA genes were analyzed using qRT-PCR method. Our study shows that administration of sodium bicarbonate in the BCSC culture medium could increase extracellular pH. To balance the increase of extracellular pH, BCSCs regulated the expression of LDH-A, LDH-B, MCT1, and MCT4 genes. As the extracellular pH increases, the expression of LDH-A that converts pyruvate to lactate increased along with the increase of MCT 4 and MCT 1 expression, which act as lactate transporters. As the incubation time increases, the pH decreases, leading to the suppression of LDH-A and increase of LDH-B expression that converts lactate into pyruvate. Therefore, we suggest that the extracellular alkalinization by sodium bicarbonate in BCSCs affected the genes that regulate lactate metabolism.

  19. An in vitro investigation of immunomodulatory properties of Lactobacillus plantarum and L. delbrueckii cells and their extracellular polysaccharides.

    Science.gov (United States)

    Kishimoto, Mana; Nomoto, Ryohei; Mizuno, Masashi; Osawa, Ro

    2017-01-01

    Many probiotic lactobacilli and their extracellular polysaccharides (EPS) have beneficial immunological properties. However, it is unclear how they elicit the host immune response. We thus investigated the immunological properties of UV-killed Lactobacillus delbrueckii TU-1 and L. plantarum KM-9 cells as well as their extracellular polysaccharides (EPSs). High-performance liquid chromatography and ion exchange chromatography analyses showed that their EPSs differ in sugar composition and sugar fractionation. The immunological properties were evaluated in a semi-intestinal model using a Transwell co-culture system that employed human intestinal epithelial (Caco-2) cells on the apical side and murine macrophage (RAW264.7) cells on the basolateral side. The UV-killed cells and EPSs were added to the apical side to allow direct contact with Caco-2 cells and incubated for 6 hr. After incubation, the amounts of tumor necrosis factor-α and several cytokines released by RAW264.7 or Caco-2 cells were quantified by cytotoxic activity on L929 cells (murine fibrosarcoma cell line) and quantitative reverse-transcriptase PCR. We found that the UV-killed cells and their EPSs had immunological effects on RAW264.7 cells via Caco-2 cells. The RAW264.7 cells showed different cytokine production profiles when treated with UV-killed cells and EPSs. The UV-killed cells and EPSs promoted a Th1-type cellular response. Furthermore, we found that the UV-killed cells sent positive signals through Toll-like receptor (TLR) 2. Meanwhile, neither EPS sent a positive signal through TLR4 and TLR2. This evidence suggests that both UV-killed cells of the lactobacillus strains and their EPSs trigger a Th1-type immune response in a human host, with the former triggering the response via the TLRs expressed on its epithelium and the latter employing a mechanism yet to be determined, possibly involving a novel receptor that is designed to recognize specific patterns of repeating sugar in the EPSs.

  20. Cell adhesion-mediated radioresistance (CAM-RR). Extracellular matrix-dependent improvement of cell survival in human tumor and normal cells in vitro

    International Nuclear Information System (INIS)

    Cordes, N.; Meineke, V.

    2003-01-01

    Background: Cell-extracellular matrix (ECM) contact is thought to have great impact on cellular mechanisms resulting in increased cell survival upon exposure to ionizing radiation. Several human tumor cell lines and normal human fibroblastic cell strains of different origin, all of them expressing the wide-spread and important integrin subunit β1, were irradiated, and clonogenic cell survival, β1-integrin cell surface expression, and adhesive functionality were investigated. Material and Methods: Human tumor cell lines A172 (glioblastoma), PATU8902 (pancreas carcinoma), SKMES1 (lung carcinoma), A549 (lung carcinoma), and IPC298 (melanoma) as well as normal human skin (HSF1) and lung fibroblasts (CCD32) and human keratinocytes (HaCaT) were irradiated with 0-8 Gy. Besides colony formation assays, β1-integrin cell surface expression by flow cytometry and adhesive functionality by adhesion assays were analyzed. Results: All cell lines showed improved clonogenic survival after irradiation in the presence of fibronectin as compared to plastic. Irradiated cells exhibited a significant, dose-dependent increase in β1-integrin cell surface expression following irradiation. As a parameter of the adhesive functionality of the β1-integrin, a radiation-dependent elevation of cell adhesion to fibronectin in comparison with adhesion to plastic was demonstrated. Conclusion: The in vitro cellular radiosensitivity is highly influenced by fibronectin according to the phenomenon of cell adhesion-mediated radioresistance. Additionally, our emerging data question the results of former and current in vitro cytotoxicity studies performed in the absence of an ECM. These findings might also be important for the understanding of malignant transformation, anchorage-independent cell growth, optimization of radiotherapeutic regimes and the prevention of normal tissue side effects on the basis of experimental radiobiological data. (orig.)

  1. Extracellular acidification induces connective tissue growth factor production through proton-sensing receptor OGR1 in human airway smooth muscle cells

    International Nuclear Information System (INIS)

    Matsuzaki, Shinichi; Ishizuka, Tamotsu; Yamada, Hidenori; Kamide, Yosuke; Hisada, Takeshi; Ichimonji, Isao; Aoki, Haruka; Yatomi, Masakiyo; Komachi, Mayumi; Tsurumaki, Hiroaki; Ono, Akihiro; Koga, Yasuhiko; Dobashi, Kunio; Mogi, Chihiro; Sato, Koichi; Tomura, Hideaki; Mori, Masatomo; Okajima, Fumikazu

    2011-01-01

    Highlights: → The involvement of extracellular acidification in airway remodeling was investigated. → Extracellular acidification alone induced CTGF production in human ASMCs. → Extracellular acidification enhanced TGF-β-induced CTGF production in human ASMCs. → Proton-sensing receptor OGR1 was involved in acidic pH-stimulated CTGF production. → OGR1 may play an important role in airway remodeling in asthma. -- Abstract: Asthma is characterized by airway inflammation, hyper-responsiveness and remodeling. Extracellular acidification is known to be associated with severe asthma; however, the role of extracellular acidification in airway remodeling remains elusive. In the present study, the effects of acidification on the expression of connective tissue growth factor (CTGF), a critical factor involved in the formation of extracellular matrix proteins and hence airway remodeling, were examined in human airway smooth muscle cells (ASMCs). Acidic pH alone induced a substantial production of CTGF, and enhanced transforming growth factor (TGF)-β-induced CTGF mRNA and protein expression. The extracellular acidic pH-induced effects were inhibited by knockdown of a proton-sensing ovarian cancer G-protein-coupled receptor (OGR1) with its specific small interfering RNA and by addition of the G q/11 protein-specific inhibitor, YM-254890, or the inositol-1,4,5-trisphosphate (IP 3 ) receptor antagonist, 2-APB. In conclusion, extracellular acidification induces CTGF production through the OGR1/G q/11 protein and inositol-1,4,5-trisphosphate-induced Ca 2+ mobilization in human ASMCs.

  2. Tumour cell–derived extracellular vesicles interact with mesenchymal stem cells to modulate the microenvironment and enhance cholangiocarcinoma growth

    Directory of Open Access Journals (Sweden)

    Hiroaki Haga

    2015-01-01

    Full Text Available The contributions of mesenchymal stem cells (MSCs to tumour growth and stroma formation are poorly understood. Tumour cells can transfer genetic information and modulate cell signalling in other cells through the release of extracellular vesicles (EVs. We examined the contribution of EV-mediated inter-cellular signalling between bone marrow MSCs and tumour cells in human cholangiocarcinoma, highly desmoplastic cancers that are characterized by tumour cells closely intertwined within a dense fibrous stroma. Exposure of MSCs to tumour cell–derived EVs enhanced MSC migratory capability and expression of alpha-smooth muscle actin mRNA, in addition to mRNA expression and release of CXCL-1, CCL2 and IL-6. Conditioned media from MSCs exposed to tumour cell–derived EVs increased STAT-3 phosphorylation and proliferation in tumour cells. These effects were completely blocked by anti-IL-6R antibody. In conclusion, tumour cell–derived EVs can contribute to the generation of tumour stroma through fibroblastic differentiation of MSCs, and can also selectively modulate the cellular release of soluble factors such as IL-6 by MSCs that can, in turn, alter tumour cell proliferation. Thus, malignant cells can “educate” MSCs to induce local microenvironmental changes that enhance tumour cell growth.

  3. Effects of cell-attachment and extracellular matrix on bone formation in vivo in collagen-hydroxyapatite scaffolds.

    Science.gov (United States)

    Villa, Max M; Wang, Liping; Rowe, David W; Wei, Mei

    2014-01-01

    Cell-based tissue engineering can be used to replace missing or damaged bone, but the optimal methods for delivering therapeutic cells to a bony defect have not yet been established. Using transgenic reporter cells as a donor source, two different collagen-hydroxyapatite (HA) scaffolds, and a critical-size calvarial defect model, we investigated the effect of a cell-attachment period prior to implantation, with or without an extracellular matrix-based seeding suspension, on cell engraftment and osteogenesis. When quantitatively compared, the in-house scaffold implanted immediately had a higher mean radiopacity than in-house scaffolds incubated overnight. Both scaffold types implanted immediately had significantly higher area fractions of donor cells, while the in-house collagen-HA scaffolds implanted immediately had higher area fractions of the mineralization label compared with groups incubated overnight. When the cell loading was compared in vitro for each delivery method using the in-house scaffold, immediate loading led to higher numbers of delivered cells. Immediate loading may be preferable in order to ensure robust bone formation in vivo. The use of a secondary ECM carrier improved the distribution of donor cells only when a pre-attachment period was applied. These results have improved our understanding of cell delivery to bony defects in the context of in vivo outcomes.

  4. Extracellular Matrix-Mediated Maturation of Human Pluripotent Stem Cell-Derived Cardiac Monolayer Structure and Electrophysiological Function.

    Science.gov (United States)

    Herron, Todd J; Rocha, Andre Monteiro Da; Campbell, Katherine F; Ponce-Balbuena, Daniela; Willis, B Cicero; Guerrero-Serna, Guadalupe; Liu, Qinghua; Klos, Matt; Musa, Hassan; Zarzoso, Manuel; Bizy, Alexandra; Furness, Jamie; Anumonwo, Justus; Mironov, Sergey; Jalife, José

    2016-04-01

    Human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) monolayers generated to date display an immature embryonic-like functional and structural phenotype that limits their utility for research and cardiac regeneration. In particular, the electrophysiological function of hPSC-CM monolayers and bioengineered constructs used to date are characterized by slow electric impulse propagation velocity and immature action potential profiles. Here, we have identified an optimal extracellular matrix for significant electrophysiological and structural maturation of hPSC-CM monolayers. hPSC-CM plated in the optimal extracellular matrix combination have impulse propagation velocities ≈2× faster than previously reported (43.6±7.0 cm/s; n=9) and have mature cardiomyocyte action potential profiles, including hyperpolarized diastolic potential and rapid action potential upstroke velocity (146.5±17.7 V/s; n=5 monolayers). In addition, the optimal extracellular matrix promoted hypertrophic growth of cardiomyocytes and the expression of key mature sarcolemmal (SCN5A, Kir2.1, and connexin43) and myofilament markers (cardiac troponin I). The maturation process reported here relies on activation of integrin signaling pathways: neutralization of β1 integrin receptors via blocking antibodies and pharmacological blockade of focal adhesion kinase activation prevented structural maturation. Maturation of human stem cell-derived cardiomyocyte monolayers is achieved in a 1-week period by plating cardiomyocytes on PDMS (polydimethylsiloxane) coverslips rather than on conventional 2-dimensional cell culture formats, such as glass coverslips or plastic dishes. Activation of integrin signaling and focal adhesion kinase is essential for significant maturation of human cardiac monolayers. © 2016 American Heart Association, Inc.

  5. Extracellular gentamicin reduces the activity of connexin hemichannels and interferes with purinergic Ca2+ signaling in HeLa cells

    Science.gov (United States)

    Figueroa, Vania A.; Retamal, Mauricio A.; Cea, Luis A.; Salas, José D.; Vargas, Aníbal A.; Verdugo, Christian A.; Jara, Oscar; Martínez, Agustín D.; Sáez, Juan C.

    2014-01-01

    Gap junction channels (GJCs) and hemichannels (HCs) are composed of protein subunits termed connexins (Cxs) and are permeable to ions and small molecules. In most organs, GJCs communicate the cytoplasm of adjacent cells, while HCs communicate the intra and extracellular compartments. In this way, both channel types coordinate physiological responses of cell communities. Cx mutations explain several genetic diseases, including about 50% of autosomal recessive non-syndromic hearing loss. However, the possible involvement of Cxs in the etiology of acquired hearing loss remains virtually unknown. Factors that induce post-lingual hearing loss are diverse, exposure to gentamicin an aminoglycoside antibiotic, being the most common. Gentamicin has been proposed to block GJCs, but its effect on HCs remains unknown. In this work, the effect of gentamicin on the functional state of HCs was studied and its effect on GJCs was reevaluated in HeLa cells stably transfected with Cxs. We focused on Cx26 because it is the main Cx expressed in the cochlea of mammals where it participates in purinergic signaling pathways. We found that gentamicin applied extracellularly reduces the activity of HCs, while dye transfer across GJCs was not affected. HCs were also blocked by streptomycin, another aminoglycoside antibiotic. Gentamicin also reduced the adenosine triphosphate release and the HC-dependent oscillations of cytosolic free-Ca2+ signal. Moreover, gentamicin drastically reduced the Cx26 HC-mediated membrane currents in Xenopus laevis oocytes. Therefore, the extracellular gentamicin-induced inhibition of Cx HCs may adversely affect autocrine and paracrine signaling, including the purinergic one, which might partially explain its ototoxic effects. PMID:25237294

  6. Unexpected features of exponentially growing Tobacco Bright Yellow-2 cell suspension culture in relation to excreted extracellular polysaccharides and cell wall composition.

    Science.gov (United States)

    Issawi, Mohammad; Muhieddine, Mohammad; Girard, Celine; Sol, Vincent; Riou, Catherine

    2017-10-01

    This article presents a new insight about TBY-2 cells; from extracellular polysaccharides secretion to cell wall composition during cell suspension culture. In the medium of cells taken 2 days after dilution (end of lag phase), a two unit pH decrease from 5.38 to 3.45 was observed and linked to a high uronic acid (UA) amount secretion (47.8%) while, in 4 and 7 day-old spent media, pH increased and UA amounts decreased 35.6 and 42.3% UA, respectively. To attain deeper knowledge of the putative link between extracellular polysaccharide excretion and cell wall composition, we determined cell wall UA and neutral sugar composition of cells from D2 to D12 cultures. While cell walls from D2 and D3 cells contained a large amount of uronic acid (twice as much as the other analysed cell walls), similar amounts of neutral sugar were detected in cells from lag to end of exponential phase cells suggesting an enriched pectin network in young cultures. Indeed, monosaccharide composition analysis leads to an estimated percentage of pectins of 56% for D3 cell wall against 45% D7 cell walls indicating that the cells at the mid-exponential growth phase re-organized their cell wall linked to a decrease in secreted UA that finally led to a stabilization of the spent medium pH to 5.4. In conclusion, TBY-2 cell suspension from lag to stationary phase showed cell wall remodeling that could be of interest in drug interaction and internalization study.

  7. Electrochemical noise and impedance of Au electrode/electrolyte interfaces enabling extracellular detection of glioma cell populations.

    Science.gov (United States)

    Rocha, Paulo R F; Schlett, Paul; Kintzel, Ulrike; Mailänder, Volker; Vandamme, Lode K J; Zeck, Gunther; Gomes, Henrique L; Biscarini, Fabio; de Leeuw, Dago M

    2016-10-06

    Microelectrode arrays (MEA) record extracellular local field potentials of cells adhered to the electrodes. A disadvantage is the limited signal-to-noise ratio. The state-of-the-art background noise level is about 10 μVpp. Furthermore, in MEAs low frequency events are filtered out. Here, we quantitatively analyze Au electrode/electrolyte interfaces with impedance spectroscopy and noise measurements. The equivalent circuit is the charge transfer resistance in parallel with a constant phase element that describes the double layer capacitance, in series with a spreading resistance. This equivalent circuit leads to a Maxwell-Wagner relaxation frequency, the value of which is determined as a function of electrode area and molarity of an aqueous KCl electrolyte solution. The electrochemical voltage and current noise is measured as a function of electrode area and frequency and follow unambiguously from the measured impedance. By using large area electrodes the noise floor can be as low as 0.3 μVpp. The resulting high sensitivity is demonstrated by the extracellular detection of C6 glioma cell populations. Their minute electrical activity can be clearly detected at a frequency below about 10 Hz, which shows that the methodology can be used to monitor slow cooperative biological signals in cell populations.

  8. Effect of SLC34A2 gene mutation on extracellular phosphorus transport in PAM alveolar epithelial cells.

    Science.gov (United States)

    Ma, Tiangang; Qu, Danhua; Yan, Bingdi; Zhang, Qinghua; Ren, Jin; Hu, Yanbing

    2018-01-01

    A mutation in the IIb sodium phosphate transporter SLC34A2 gene has recently been described in pulmonary alveolar microlithiasis (PAM) patients. Experiments in this study were aimed at confirming the role of the gene product in PAM by comparing phosphorylated products in extracellular fluid of alveolar epithelial cells overexpressing the SLC34A2 gene or its mutated version. Eukaryotic expression vectors were constructed and transfected into A549 human alveolar epithelial cells. There were three groups of cells including those transfected with empty vector plasmid pcDNA3.1(+) (plasmid control group), those transfected with normal SLC34A2 gene expressed from pcDNA3.1 (normal control group), and those transfected with a version of the PAM SLC34A2 gene linked to the pcDNA3.1(+) (PAM group). Transfection efficiencies were detected by reverse transcription-polymerase chain reaction (RT-PCR). At 48 h after transfection, the concentration of inorganic phosphorus in the culture medium was detected using an automatic biochemical analyzer. Our results showed the concentration of inorganic phosphorus in the supernatant of the normal control group was significantly lower than that in the plasmid control and PAM groups (PPAM group was significantly lower than that in the plasmid control group (PPAM patients, given that the function of the phosphate transporter seems to be affected and it is conceivable that it would lead to extracellular fluid alterations in vivo .

  9. Influence of substrate composition on human embryonic stem cell differentiation and extracellular matrix production in embryoid bodies.

    Science.gov (United States)

    Laperle, Alex; Masters, Kristyn S; Palecek, Sean P

    2015-01-01

    Stem cells reside in specialized niches in vivo. Specific factors, including the extracellular matrix (ECM), in these niches are directly responsible for maintaining the stem cell population. During development, components of the stem cell microenvironment also control differentiation with precise spatial and temporal organization. The stem cell microenvironment is dynamically regulated by the cellular component, including stem cells themselves. Thus, a mechanism exists whereby stem cells modify the ECM, which in turn affects the fate of the stem cell. In this study, we investigated whether the type of ECM initially adsorbed to the culture substrate can influence the composition of the ECM deposited by human embryonic stem cells (hESCs) differentiating in embryoid bodies, and whether different ECM composition and deposition profiles elicit distinct differentiation fates. We have shown that the initial ECM environment hESCs are exposed to affects the fate decisions of those cells and that this initial ECM environment is constantly modified during the differentiation process. © 2014 American Institute of Chemical Engineers.

  10. Deletion of the calmodulin-binding domain of Grb7 impairs cell attachment to the extracellular matrix and migration

    Energy Technology Data Exchange (ETDEWEB)

    García-Palmero, Irene; Villalobo, Antonio, E-mail: antonio.villalobo@iib.uam.es

    2013-06-28

    Highlights: •Grb7 is a calmodulin (CaM)-binding protein. •Deleting the CaM-binding site impairs cell attachment and migration. •CaM antagonists inhibit Grb7-mediated cell migration. •We conclude that CaM controls Grb7-mediated cell migration. -- Abstract: The adaptor Grb7 is a calmodulin (CaM)-binding protein that participates in signaling pathways involved in cell migration, proliferation and the control of angiogenesis, and plays a significant role in tumor growth, its metastatic spread and tumor-associated neo-vasculature formation. In this report we show that deletion of the CaM-binding site of Grb7, located in the proximal region of its pleckstrin homology (PH) domain, impairs cell migration, cell attachment to the extracellular matrix, and the reorganization of the actin cytoskeleton occurring during this process. Moreover, we show that the cell-permeable CaM antagonists N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide (W-7) and N-(4-aminobutyl)-5-chloro-2-naphthalenesulfonamide (W-13) both retard the migration of cells expressing wild type Grb7, but not the migration of cells expressing the mutant protein lacking the CaM-binding site (Grb7Δ), underscoring the proactive role of CaM binding to Grb7 during this process.

  11. A vibrating membrane bioreactor operated at supra- and sub-critical flux: Influence of extracellular polymeric substances from yeast cells

    DEFF Research Database (Denmark)

    Beier, Søren Prip; Jonsson, Gunnar Eigil

    2007-01-01

    A vibrating membrane bioreactor, in which the fouling problems are reduced by vibrating a hollow fiber membrane module, has been tested in constant flux microfiltration above (supra-critical) and below (sub-critical) an experimentally determined critical flux. Suspensions of bakers yeast cells were...... chosen as filtration medium (dry weight 4 g/l). The influence of extracellular polymeric substances (EPS) from the yeast cells is evaluated by UV absorbance measurements of the bulk supernatant during filtration. The critical flux seems to be an interval or a relative value rather than an absolute value....... Filtration just below the critical flux (sub-critical) seems to be a good compromise between acceptable flux level and acceptable increase of fouling resistance and trans-membrane pressure (TMP) in a given time period. EPS from the yeast cells causes the membrane module to foul and part of the fouling...

  12. NMR quantification of diffusional exchange in cell suspensions with relaxation rate differences between intra and extracellular compartments.

    Science.gov (United States)

    Eriksson, Stefanie; Elbing, Karin; Söderman, Olle; Lindkvist-Petersson, Karin; Topgaard, Daniel; Lasič, Samo

    2017-01-01

    Water transport across cell membranes can be measured non-invasively with diffusion NMR. We present a method to quantify the intracellular lifetime of water in cell suspensions with short transverse relaxation times, T2, and also circumvent the confounding effect of different T2 values in the intra- and extracellular compartments. Filter exchange spectroscopy (FEXSY) is specifically sensitive to exchange between compartments with different apparent diffusivities. Our investigation shows that FEXSY could yield significantly biased results if differences in T2 are not accounted for. To mitigate this problem, we propose combining FEXSY with diffusion-relaxation correlation experiment, which can quantify differences in T2 values in compartments with different diffusivities. Our analysis uses a joint constrained fitting of the two datasets and considers the effects of diffusion, relaxation and exchange in both experiments. The method is demonstrated on yeast cells with and without human aquaporins.

  13. The regulation of growth and metabolism of kidney stem cells with regional specificity using extracellular matrix derived from kidney.

    Science.gov (United States)

    O'Neill, John D; Freytes, Donald O; Anandappa, Annabelle J; Oliver, Juan A; Vunjak-Novakovic, Gordana V

    2013-12-01

    Native extracellular matrix (ECM) that is secreted and maintained by resident cells is of great interest for cell culture and cell delivery. We hypothesized that specialized bioengineered niches for stem cells can be established using ECM-derived scaffolding materials. Kidney was selected as a model system because of the high regional diversification of renal tissue matrix. By preparing the ECM from three specialized regions of the kidney (cortex, medulla, and papilla; whole kidney, heart, and bladder as controls) in three forms: (i) intact sheets of decellularized ECM, (ii) ECM hydrogels, and (iii) solubilized ECM, we investigated how the structure and composition of ECM affect the function of kidney stem cells (with mesenchymal stem cells, MSCs, as controls). All three forms of the ECM regulated KSC function, with differential structural and compositional effects. KSCs cultured on papilla ECM consistently displayed lower proliferation, higher metabolic activity, and differences in cell morphology, alignment, and structure formation as compared to KSCs on cortex and medulla ECM, effects not observed in corresponding MSC cultures. These data suggest that tissue- and region-specific ECM can provide an effective substrate for in vitro studies of therapeutic stem cells. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Coating extracellular matrix proteins on a (3-aminopropyl)triethoxysilane-treated glass substrate for improved cell culture.

    Science.gov (United States)

    Masuda, Hiro-taka; Ishihara, Seiichiro; Harada, Ichiro; Mizutani, Takeomi; Ishikawa, Masayori; Kawabata, Kazushige; Haga, Hisashi

    2014-01-01

    We demonstrate that a (3-aminopropyl)triethoxysilane-treated glass surface is superior to an untreated glass surface for coating with extracellular matrix (ECM) proteins when used as a cell culture substrate to observe cell physiology and behavior. We found that MDCK cells cultured on untreated glass coated with ECM removed the coated ECM protein and secreted different ECM proteins. In contrast, the cells did not remove the coated ECM protein when seeded on (3-aminopropyl)triethoxysilane-treated (i.e., silanized) glass coated with ECM. Furthermore, the morphology and motility of cells grown on silanized glass differed from those grown on non-treated glass, even when both types of glass were initially coated with laminin. We also found that cells on silanized glass coated with laminin had higher motility than those on silanized glass coated with fibronectin. Based on our results, we suggest that silanized glass is a more suitable cell culture substrate than conventional non-treated glass when coated by ECM for observations of ECM effects on cell physiology.

  15. Mesenchymal stem cell proliferation and mineralization but not osteogenic differentiation are strongly affected by extracellular pH.

    Science.gov (United States)

    Fliefel, Riham; Popov, Cvetan; Tröltzsch, Matthias; Kühnisch, Jan; Ehrenfeld, Michael; Otto, Sven

    2016-06-01

    Osteomyelitis is a serious complication in oral and maxillofacial surgery affecting bone healing. Bone remodeling is not only controlled by cellular components but also by ionic and molecular composition of the extracellular fluids in which calcium phosphate salts are precipitated in a pH dependent manner. To determine the effect of pH on self-renewal, osteogenic differentiation and matrix mineralization of mesenchymal stem cells (MSCs). We selected three different pH values; acidic (6.3, 6.7), physiological (7.0-8.0) and severe alkaline (8.5). MSCs were cultured at different pH ranges, cell viability measured by WST-1, apoptosis detected by JC-1, senescence was analyzed by β-galactosidase whereas mineralization was detected by Alizarin Red and osteogenic differentiation analyzed by Real-time PCR. Self-renewal was affected by pH as well as matrix mineralization in which pH other than physiologic inhibited the deposition of extracellular matrix but did not affect MSCs differentiation as osteoblast markers were upregulated. The expression of osteocalcin and alkaline phosphatase activity was upregulated whereas osteopontin was downregulated under acidic pH. pH affected MSCs self-renewal and mineralization without influencing osteogenic differentiation. Thus, future therapies, based on shifting acid-base balance toward the alkaline direction might be beneficial for prevention or treatment of osteomyelitis. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

  16. CD81 Receptor Regions outside the Large Extracellular Loop Determine Hepatitis C Virus Entry into Hepatoma Cells

    Directory of Open Access Journals (Sweden)

    Pia Banse

    2018-04-01

    Full Text Available Hepatitis C virus (HCV enters human hepatocytes using four essential entry factors, one of which is human CD81 (hCD81. The tetraspanin hCD81 contains a large extracellular loop (LEL, which interacts with the E2 glycoprotein of HCV. The role of the non-LEL regions of hCD81 (intracellular tails, four transmembrane domains, small extracellular loop and intracellular loop is poorly understood. Here, we studied the contribution of these domains to HCV susceptibility of hepatoma cells by generating chimeras of related tetraspanins with the hCD81 LEL. Our results show that non-LEL regions in addition to the LEL determine susceptibility of cells to HCV. While closely related tetraspanins (X. tropicalis CD81 and D. rerio CD81 functionally complement hCD81 non-LEL regions, distantly related tetraspanins (C. elegans TSP9 amd D. melanogaster TSP96F do not and tetraspanins with intermediate homology (hCD9 show an intermediate phenotype. Tetraspanin homology and susceptibility to HCV correlate positively. For some chimeras, infectivity correlates with surface expression. In contrast, the hCD9 chimera is fully surface expressed, binds HCV E2 glycoprotein but is impaired in HCV receptor function. We demonstrate that a cholesterol-coordinating glutamate residue in CD81, which hCD9 lacks, promotes HCV infection. This work highlights the hCD81 non-LEL regions as additional HCV susceptibility-determining factors.

  17. A Carbohydrate Moiety of Secreted Stage-Specific Glycoprotein 4 Participates in Host Cell Invasion by Trypanosoma cruzi Extracellular Amastigotes

    Directory of Open Access Journals (Sweden)

    Pilar T. V. Florentino

    2018-04-01

    Full Text Available Trypanosoma cruzi is the etiologic agent of Chagas’ disease. It is known that amastigotes derived from trypomastigotes in the extracellular milieu are infective in vitro and in vivo. Extracellular amastigotes (EAs have a stage-specific surface antigen called Ssp-4, a GPI-anchored glycoprotein that is secreted by the parasites. By immunoprecipitation with the Ssp-4-specific monoclonal antibodies (mAb 2C2 and 1D9, we isolated the glycoprotein from EAs. By mass spectrometry, we identified the core protein of Ssp-4 and evaluated mRNA expression and the presence of Ssp-4 carbohydrate epitopes recognized by mAb1D9. We demonstrated that the carbohydrate epitope recognized by mAb1D9 could promote host cell invasion by EAs. Although infectious EAs express lower amounts of Ssp-4 compared with less-infectious EAs (at the mRNA and protein levels, it is the glycosylation of Ssp-4 (identified by mAb1D9 staining only in infectious strains and recognized by galectin-3 on host cells that is the determinant of EA invasion of host cells. Furthermore, Ssp-4 is secreted by EAs, either free or associated with parasite vesicles, and can participate in host-cell interactions. The results presented here describe the possible role of a carbohydrate moiety of T. cruzi surface glycoproteins in host cell invasion by EA forms, highlighting the potential of these moieties as therapeutic and vaccine targets for the treatment of Chagas’ disease.

  18. A Carbohydrate Moiety of Secreted Stage-Specific Glycoprotein 4 Participates in Host Cell Invasion by Trypanosoma cruzi Extracellular Amastigotes

    Science.gov (United States)

    Florentino, Pilar T. V.; Real, Fernando; Orikaza, Cristina M.; da Cunha, Julia P. C.; Vitorino, Francisca N. L.; Cordero, Esteban M.; Sobreira, Tiago J. P.; Mortara, Renato A.

    2018-01-01

    Trypanosoma cruzi is the etiologic agent of Chagas’ disease. It is known that amastigotes derived from trypomastigotes in the extracellular milieu are infective in vitro and in vivo. Extracellular amastigotes (EAs) have a stage-specific surface antigen called Ssp-4, a GPI-anchored glycoprotein that is secreted by the parasites. By immunoprecipitation with the Ssp-4-specific monoclonal antibodies (mAb) 2C2 and 1D9, we isolated the glycoprotein from EAs. By mass spectrometry, we identified the core protein of Ssp-4 and evaluated mRNA expression and the presence of Ssp-4 carbohydrate epitopes recognized by mAb1D9. We demonstrated that the carbohydrate epitope recognized by mAb1D9 could promote host cell invasion by EAs. Although infectious EAs express lower amounts of Ssp-4 compared with less-infectious EAs (at the mRNA and protein levels), it is the glycosylation of Ssp-4 (identified by mAb1D9 staining only in infectious strains and recognized by galectin-3 on host cells) that is the determinant of EA invasion of host cells. Furthermore, Ssp-4 is secreted by EAs, either free or associated with parasite vesicles, and can participate in host-cell interactions. The results presented here describe the possible role of a carbohydrate moiety of T. cruzi surface glycoproteins in host cell invasion by EA forms, highlighting the potential of these moieties as therapeutic and vaccine targets for the treatment of Chagas’ disease. PMID:29692765

  19. Integrin-mediated adhesion of human mesenchymal stem cells to extracellular matrix proteins adsorbed to polymer surfaces

    International Nuclear Information System (INIS)

    Dånmark, S; Mustafa, K; Finne-Wistrand, A; Albertsson, A-C; Patarroyo, M

    2012-01-01

    In vitro, degradable aliphatic polyesters are widely used as cell carriers for bone tissue engineering, despite their lack of biological cues. Their biological active surface is rather determined by an adsorbed layer of proteins from the surrounding media. Initial cell fate, including adhesion and proliferation, which are key properties for efficient cell carriers, is determined by the adsorbed layer of proteins. Herein we have investigated the ability of human bone marrow derived stem cells (hBMSC) to adhere to extracellular matrix (ECM) proteins, including fibronectin and vitronectin which are present in plasma and serum. hBMSC expressed integrins for collagens, laminins, fibronectin and vitronectin. Accordingly, hBMSC strongly adhered to these purified ECM proteins by using the corresponding integrins. Although purified fibronectin and vitronectin adsorbed to aliphatic polyesters to a lower extent than to cell culture polystyrene, these low levels were sufficient to mediate adhesion of hBMSC. It was found that plasma- and serum-coated polystyrene adsorbed significant levels of both fibronectin and vitronectin, and fibronectin was identified as the major adhesive component of plasma for hBMSC; however, aliphatic polyesters adsorbed minimal levels of fibronectin under similar conditions resulting in impaired cell adhesion. Altogether, the results suggest that the efficiency of aliphatic polyesters cell carriers could be improved by increasing their ability to adsorb fibronectin. (paper)

  20. Quantitative Secretomic Analysis Identifies Extracellular Protein Factors That Modulate the Metastatic Phenotype of Non-Small Cell Lung Cancer.

    Science.gov (United States)

    Hu, Rongkuan; Huffman, Kenneth E; Chu, Michael; Zhang, Yajie; Minna, John D; Yu, Yonghao

    2016-02-05

    Lung cancer is the leading cause of cancer-related deaths for men and women in the United States, with non-small cell lung cancer (NSCLC) representing 85% of all diagnoses. Late stage detection, metastatic disease and lack of actionable biomarkers contribute to the high mortality rate. Proteins in the extracellular space are known to be critically involved in regulating every stage of the pathogenesis of lung cancer. To investigate the mechanism by which secreted proteins contribute to the pathogenesis of NSCLC, we performed quantitative secretomic analysis of two isogenic NSCLC cell lines (NCI-H1993 and NCI-H2073) and an immortalized human bronchial epithelial cell line (HBEC3-KT) as control. H1993 was derived from a chemo-naïve metastatic tumor, while H2073 was derived from the primary tumor after etoposide/cisplatin therapy. From the conditioned media of these three cell lines, we identified and quantified 2713 proteins, including a series of proteins involved in regulating inflammatory response, programmed cell death and cell motion. Gene Ontology (GO) analysis indicates that a number of proteins overexpressed in H1993 media are involved in biological processes related to cancer metastasis, including cell motion, cell-cell adhesion and cell migration. RNA interference (RNAi)-mediated knock down of a number of these proteins, including SULT2B1, CEACAM5, SPRR3, AGR2, S100P, and S100A14, leads to dramatically reduced migration of these cells. In addition, meta-analysis of survival data indicates NSCLC patients whose tumors express higher levels of several of these secreted proteins, including SULT2B1, CEACAM5, SPRR3, S100P, and S100A14, have a worse prognosis. Collectively, our results provide a potential molecular link between deregulated secretome and NSCLC cell migration/metastasis. In addition, the identification of these aberrantly secreted proteins might facilitate the development of biomarkers for early detection of this devastating disease.

  1. Extracellular diffusion quantified by magnetic resonance imaging during rat C6 glioma cell progression

    Directory of Open Access Journals (Sweden)

    G. Song

    Full Text Available Solution reflux and edema hamper the convection-enhanced delivery of the standard treatment for glioma. Therefore, a real-time magnetic resonance imaging (MRI method was developed to monitor the dosing process, but a quantitative analysis of local diffusion and clearance parameters has not been assessed. The objective of this study was to compare diffusion into the extracellular space (ECS at different stages of rat C6 gliomas, and analyze the effects of the extracellular matrix (ECM on the diffusion process. At 10 and 20 days, after successful glioma modeling, gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA was introduced into the ECS of rat C6 gliomas. Diffusion parameters and half-life of the reagent were then detected using MRI, and quantified according to the mathematical model of diffusion. The main ECM components [chondroitin sulfate proteoglycans (CSPGs, collagen IV, and tenascin C] were detected by immunohistochemical and immunoblot analyses. In 20-day gliomas, Gd-DTPA diffused more slowly and derived higher tortuosity, with lower clearance rate and longer half-life compared to 10-day gliomas. The increased glioma ECM was associated with different diffusion and clearance parameters in 20-day rat gliomas compared to 10-day gliomas. ECS parameters were altered with C6 glioma progression from increased ECM content. Our study might help better understand the glioma microenvironment and provide benefits for interstitial drug delivery to treat brain gliomas.

  2. Release of ATP from Marginal Cells in the Cochlea of Neonatal Rats Can Be Induced by Changes in Extracellular and Intracellular Ion Concentrations

    Science.gov (United States)

    Peng, Yating; Chen, Jie; He, Shan; Yang, Jun; Wu, Hao

    2012-01-01

    Background Adenosine triphosphate (ATP) plays an important role in the cochlea. However, the source of ATP and the mechanism by which it is released remain unclear. This study investigates the presence and release mechanism of ATP in vitro cultured marginal cells isolated from the stria vascularis of the cochlea in neonatal rats. Methods Sprague-Dawley rats aged 1–3 days old were used for isolation, in vitro culture, and purification of marginal cells. Cultured marginal cells were verified by flow cytometry. Vesicles containing ATP in these cells were identified by fluorescence staining. The bioluminescence assay was used for determination of ATP concentration in the extracellular fluid released by marginal cells. Assays for ATP concentration were performed when the ATP metabolism of cells was influenced, and ionic concentrations in intracellular and extracellular fluid were found to change. Results Evaluation of cultured marginal cells with flow cytometry revealed the percentage of fluorescently-labeled cells as 92.9% and 81.9%, for cytokeratin and vimentin, respectively. Quinacrine staining under fluorescence microscopy revealed numerous green, star-like spots in the cytoplasm of these cells. The release of ATP from marginal cells was influenced by changes in the concentration of intracellular and extracellular ions, namely extracellular K+ and intra- and extracellular Ca2+. Furthermore, changes in the concentration of intracellular Ca2+ induced by the inhibition of the phospholipase signaling pathway also influence the release of ATP from marginal cells. Conclusion We confirmed the presence and release of ATP from marginal cells of the stria vascularis. This is the first study to demonstrate that the release of ATP from such cells is associated with the state of the calcium pump, K+ channel, and activity of enzymes related to the phosphoinositide signaling pathway, such as adenylate cyclase, phospholipase C, and phospholipase A2. PMID:23071731

  3. The emergence of extracellular matrix mechanics and cell traction forces as important regulators of cellular self-organization.

    Science.gov (United States)

    Checa, Sara; Rausch, Manuel K; Petersen, Ansgar; Kuhl, Ellen; Duda, Georg N

    2015-01-01

    Physical cues play a fundamental role in a wide range of biological processes, such as embryogenesis, wound healing, tumour invasion and connective tissue morphogenesis. Although it is well known that during these processes, cells continuously interact with the local extracellular matrix (ECM) through cell traction forces, the role of these mechanical interactions on large scale cellular and matrix organization remains largely unknown. In this study, we use a simple theoretical model to investigate cellular and matrix organization as a result of mechanical feedback signals between cells and the surrounding ECM. The model includes bi-directional coupling through cellular traction forces to deform the ECM and through matrix deformation to trigger cellular migration. In addition, we incorporate the mechanical contribution of matrix fibres and their reorganization by the cells. We show that a group of contractile cells will self-polarize at a large scale, even in homogeneous environments. In addition, our simulations mimic the experimentally observed alignment of cells in the direction of maximum stiffness and the building up of tension as a consequence of cell and fibre reorganization. Moreover, we demonstrate that cellular organization is tightly linked to the mechanical feedback loop between cells and matrix. Cells with a preference for stiff environments have a tendency to form chains, while cells with a tendency for soft environments tend to form clusters. The model presented here illustrates the potential of simple physical cues and their impact on cellular self-organization. It can be used in applications where cell-matrix interactions play a key role, such as in the design of tissue engineering scaffolds and to gain a basic understanding of pattern formation in organogenesis or tissue regeneration.

  4. Development of an in situ evaluation system for neural cells using extracellular matrix-modeled gel culture.

    Science.gov (United States)

    Nagai, Takayuki; Ikegami, Yasuhiro; Mizumachi, Hideyuki; Shirakigawa, Nana; Ijima, Hiroyuki

    2017-10-01

    Two-dimensional monolayer culture is the most popular cell culture method. However, the cells may not respond as they do in vivo because the culture conditions are different from in vivo conditions. However, hydrogel-embedding culture, which cultures cells in a biocompatible culture substrate, can produce in vivo-like cell responses, but in situ evaluation of cells in a gel is difficult. In this study, we realized an in vivo-like environment in vitro to produce cell responses similar to those in vivo and established an in situ evaluation system for hydrogel-embedded cell responses. The extracellular matrix (ECM)-modeled gel consisted of collagen and heparin (Hep-col) to mimic an in vivo-like environment. The Hep-col gel could immobilize growth factors, which is important for ECM functions. Neural stem/progenitor cells cultured in the Hep-col gel grew and differentiated more actively than in collagen, indicating an in vivo-like environment in the Hep-col gel. Second, a thin-layered gel culture system was developed to realize in situ evaluation of the gel-embedded cells. Cells in a 200-μm-thick gel could be evaluated clearly by a phase-contrast microscope and immunofluorescence staining through reduced optical and diffusional effects. Finally, we found that the neural cells cultured in this system had synaptic connections and neuronal action potentials by immunofluorescence staining and Ca 2+ imaging. In conclusion, this culture method may be a valuable evaluation system for neurotoxicity testing. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  5. From the Cover: Selective Enhancement of Domoic Acid Toxicity in Primary Cultures of Cerebellar Granule Cells by Lowering Extracellular Na+ Concentration.

    Science.gov (United States)

    Pérez-Gómez, Anabel; Cabrera-García, David; Warm, Davide; Marini, Ann M; Salas Puig, Javier; Fernández-Sánchez, Maria Teresa; Novelli, Antonello

    2018-01-01

    Domoic acid (DOM) is an excitatory amino acid analog of kainic acid (KA) that acts through glutamic acid (GLU) receptors, inducing a fast and potent neurotoxic response. Here, we present evidence for an enhancement of excitotoxicity following exposure of cultured cerebellar granule cells to DOM in the presence of lower than physiological Na+ concentrations. The concentration of DOM that reduced by 50% neuronal survival was approximately 3 µM in Na+-free conditions and 16 µM in presence of a physiological concentration of extracellular Na+. The enhanced neurotoxic effect of DOM was fully prevented by AMPA/KA receptor antagonist, while N-methyl-D-aspartate-receptor-mediated neurotoxicity did not seem to be involved, as the absence of extracellular Na+ failed to potentiate GLU excitotoxicity under the same experimental conditions. Lowering of extracellular Na+ concentration to 60 mM eliminated extracellular recording of spontaneous electrophysiological activity from cultured neurons grown on a multi electrode array and prevented DOM stimulation of the electrical activity. Although changes in the extracellular Na+ concentration did not alter the magnitude of the rapid increase in intracellular Ca2+ levels associated to DOM exposure, they did change significantly the contribution of voltage-sensitive calcium channels (VScaCs) and the recovery time to baseline. The prevention of Ca2+ influx via VSCaCs by nifedipine failed to prevent DOM toxicity at any extracellular Na+ concentration, while the reduction of extracellular Ca2+ concentration ameliorated DOM toxicity only in the absence of extracellular Na+, enhancing it in physiological conditions. Our data suggest a crucial role for extracellular Na+ concentration in determining excitotoxicity by DOM. © The Author 2017. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  6. Modulation by phytochrome of the blue light-induced extracellular acidification by leaf epidermal cells of pea (Pisum sativum L.) : a kinetic analysis

    NARCIS (Netherlands)

    Elzenga, JTM; Staal, M; Prins, HBA

    Blue light induces extracellular acidification, a prerequisite of cell expansion, in epidermis cells of young pea leaves, by stimulation of the proton pumping-ATPase activity in the plasma membrane. A transient acidification, reaching a maximum 2.5-5 min after the start of the pulse, could be

  7. Multi-tasking Sulf1/Sulf2 enzymes do not only facilitate extracellular cell signalling but also participate in cell cycle related nuclear events.

    Science.gov (United States)

    Krishnakumar, Kavithanjali; Chakravorty, Ishani; Foy, Wendy; Allen, Steve; Justo, Tiago; Mukherjee, Abir; Dhoot, Gurtej K

    2018-03-01

    This study demonstrates highly dynamic spatial and temporal pattern of SULF1/SULF2 expression in a number of neuronal cell types growing in normal culture medium that included their transient nuclear mobilisation. Their nuclear translocation became particularly apparent during cell proliferation as both SULF1/SULF2 demonstrated not only cell membrane associated expression, their known site of function but also transient nuclear mobilisation during nuclear cell division. Nuclear localisation was apparent not only by immunocytochemical staining but also confirmed by immunoblotting staining of isolated nuclear fractions of C6, U87 and N2A cells. Immunocytochemical analysis demonstrated rapid nuclear exit of both SULF1/SULF2 following cell division that was slightly delayed but not blocked in a fraction of the polyploid cells observed in C6 cells. The overexpression of both Sulf1 and Sulf2 genes in C6 and U87 cells markedly promoted in vitro growth of these cells accompanied by nuclear mobilisation while inhibition of both these genes inhibited cell proliferation with little or no nuclear SULF1/SULF2 mobilisation. SULF1/SULF2 activity in these cells thus demonstrated a clear co-ordination of extracellular cell signalling with nuclear events related to cell proliferation. Crown Copyright © 2018. Published by Elsevier Inc. All rights reserved.

  8. Layers and Multilayers of Self-Assembled Polymers: Tunable Engineered Extracellular Matrix Coatings for Neural Cell Growth.

    Science.gov (United States)

    Landry, Michael J; Rollet, Frédéric-Guillaume; Kennedy, Timothy E; Barrett, Christopher J

    2018-03-12

    Growing primary cells and tissue in long-term cultures, such as primary neural cell culture, presents many challenges. A critical component of any environment that supports neural cell growth in vivo is an appropriate 2-D surface or 3-D scaffold, typically in the form of a thin polymer layer that coats an underlying plastic or glass substrate and aims to mimic critical aspects of the extracellular matrix. A fundamental challenge to mimicking a hydrophilic, soft natural cell environment is that materials with these properties are typically fragile and are difficult to adhere to and stabilize on an underlying plastic or glass cell culture substrate. In this review, we highlight the current state of the art and overview recent developments of new artificial extracellular matrix (ECM) surfaces for in vitro neural cell culture. Notably, these materials aim to strike a balance between being hydrophilic and soft while also being thick, stable, robust, and bound well to the underlying surface to provide an effective surface to support long-term cell growth. We focus on improved surface and scaffold coating systems that can mimic the natural physicochemical properties that enhance neuronal survival and growth, applied as soft hydrophilic polymer coatings for both in vitro cell culture and for implantable neural probes and 3-D matrixes that aim to enhance stability and longevity to promote neural biocompatibility in vivo. With respect to future developments, we outline four emerging principles that serve to guide the development of polymer assemblies that function well as artificial ECMs: (a) design inspired by biological systems and (b) the employment of principles of aqueous soft bonding and self-assembly to achieve (c) a high-water-content gel-like coating that is stable over time in a biological environment and possesses (d) a low modulus to more closely mimic soft, compliant real biological tissue. We then highlight two emerging classes of thick material coatings that

  9. Simultaneous quantification of monoamine neurotransmitters and their biogenic metabolites intracellularly and extracellularly in primary neuronal cell cultures and in sub-regions of guinea pig brain

    DEFF Research Database (Denmark)

    Schou-Pedersen, Anne Marie Voigt; Hansen, Stine Normann; Tveden-Nyborg, Pernille

    2016-01-01

    In the present paper, we describe a validated chromatographic method for the simultaneous quantification of monoamine neurotransmitters and their biogenic metabolites intracellularly and extracellularly in primary neuronal cell culture and in sub-regions of the guinea pig brain. Electrochemical...... of intracellular and extracellular amounts of monoamine neurotransmitters and their metabolites in guinea pig frontal cortex and hippocampal primary neuronal cell cultures. Noradrenaline, dopamine and serotonin were found to be in a range from 0.31 to 1.7 pmol per 2 million cells intracellularly, but only...... the biogenic metabolites could be detected extracellularly. Distinct differences in monoamine concentrations were observed when comparing concentrations in guinea pig frontal cortex and cerebellum tissue with higher amounts of dopamine and its metabolites, 3,4-dihydroxyphenylacetic acid and homovanillic acid...

  10. Extraction and Characterization of Extracellular Proteins and Their Post-Translational Modifications from Arabidopsis thaliana Suspension Cell Cultures and Seedlings: A Critical Review

    Directory of Open Access Journals (Sweden)

    Mina Ghahremani

    2016-09-01

    Full Text Available Proteins secreted by plant cells into the extracellular space, consisting of the cell wall, apoplastic fluid, and rhizosphere, play crucial roles during development, nutrient acquisition, and stress acclimation. However, isolating the full range of secreted proteins has proven difficult, and new strategies are constantly evolving to increase the number of proteins that can be detected and identified. In addition, the dynamic nature of the extracellular proteome presents the further challenge of identifying and characterizing the post-translational modifications (PTMs of secreted proteins, particularly glycosylation and phosphorylation. Such PTMs are common and important regulatory modifications of proteins, playing a key role in many biological processes. This review explores the most recent methods in isolating and characterizing the plant extracellular proteome with a focus on the model plant Arabidopsis thaliana, highlighting the current challenges yet to be overcome. Moreover, the crucial role of protein PTMs in cell wall signalling, development, and plant responses to biotic and abiotic stress is discussed.

  11. Establishment of an isolation method of Nostoc commune cells free from extracellular polysaccharides (EPS using Percoll centrifugation

    Directory of Open Access Journals (Sweden)

    Makiko Kosugi

    2012-11-01

    Full Text Available The terrestrial cyanobacterium Nostoc commune Vaucher ex Bornet et Flahault occurs worldwide, including in Japan and Antarctica. N. commune has a large amount of extracellular polysaccharides (EPS that hold moisture and protect the cells and at the same time accumulate light-blocking substances which is believed to play an important part in adaptation to a severe environment. To evaluate the photoadaptation processes in N. commune and clarify the role(s of EPS under ambient environmental condition at Antarctica, separation of cells from EPS is necessary. High yield is a prerequisite for the use of only small amount of natural N. commune from Antarctica. For this purpose, we developed a separation method by improving the Percoll density gradient centrifugation method using an EPS-coated field-grown Nostoc population. We established the most suitable condition to separate naked cells from EPS at high yield retaining high photosynthetic activity. The method is composed of centrifugation of cell homogenated N. commune in 10% (v/v Percoll to separate cells efficiently from EPS followed by fractionating centrifugation to remove impurities using the gradient of Percoll (80% and 50%, v/v.

  12. The impact of extracellular matrix coatings on the performance of human renal cells applied in bioartificial kidneys.

    Science.gov (United States)

    Zhang, Huishi; Tasnim, Farah; Ying, Jackie Y; Zink, Daniele

    2009-05-01

    Extracellular matrix (ECM) coatings have been used to improve cell performance in bioartificial kidneys (BAKs). However, their effects on primary human renal proximal tubule cells (HPTCs), which is the most important cell type with regard to clinical applications, have not been tested systematically. Also, the effects of ECM coatings on cell performance during extended time periods have not been addressed. Studying such effects is important for the development of long-term applications. Herein we analyzed for the first time systematically the effects of ECM coatings on proliferation and differentiation of human renal cells and we addressed, in particular, formation and long-term maintenance of differentiated epithelia. Our study focused on HPTCs. ECM coatings were tested alone or in combination with the growth factor bone morphogenetic protein-7 and other additives. The best results were obtained with ECMs consisting of the basal lamina components, laminin or collagen IV, and differentiated epithelia could be maintained up to three weeks on these ECMs. These results provide for the first time clear evidence which kinds of ECM coatings are most appropriate for BAKs. The results also showed that alpha-SMA-expressing myofibroblasts played a key role in the final disruption of differentiated epithelia. This suggests that epithelial-to-mesenchymal transition-related processes might be the major obstacle in long-term applications and such processes should be carefully addressed in future BAK-related research.

  13. Anti-Donor Immune Responses Elicited by Allogeneic Mesenchymal Stem Cells and Their Extracellular Vesicles: Are We Still Learning?

    Directory of Open Access Journals (Sweden)

    Paul Lohan

    2017-11-01

    Full Text Available Mesenchymal stromal cells (MSC have been used to treat a broad range of disease indications such as acute and chronic inflammatory disorders, autoimmune diseases, and transplant rejection due to their potent immunosuppressive/anti-inflammatory properties. The breadth of their usage is due in no small part to the vast quantity of published studies showing their ability to modulate multiple immune cell types of both the innate and adaptive immune response. While patient-derived (autologous MSC may be the safer choice in terms of avoiding unwanted immune responses, factors including donor comorbidities may preclude these cells from use. In these situations, allogeneic MSC derived from genetically unrelated individuals must be used. While allogeneic MSC were initially believed to be immune-privileged, substantial evidence now exists to prove otherwise with multiple studies documenting specific cellular and humoral immune responses against donor antigens following administration of these cells. In this article, we will review recent published studies using non-manipulated, inflammatory molecule-activated (licensed and differentiated allogeneic MSC, as well as MSC extracellular vesicles focusing on the immune responses to these cells and whether or not such responses have an impact on allogeneic MSC-mediated safety and efficacy.

  14. An In Vitro Potency Assay for Monitoring the Immunomodulatory Potential of Stromal Cell-Derived Extracellular Vesicles

    Directory of Open Access Journals (Sweden)

    Karin Pachler

    2017-07-01

    Full Text Available The regenerative and immunomodulatory activity of mesenchymal stromal cells (MSCs is partially mediated by secreted vesicular factors. Extracellular vesicles (EVs exocytosed by MSCs are gaining increased attention as prospective non-cellular therapeutics for a variety of diseases. However, the lack of suitable in vitro assays to monitor the therapeutic potential of EVs currently restricts their application in clinical studies. We have evaluated a dual in vitro immunomodulation potency assay that reproducibly reports the inhibitory effect of MSCs on induced T-cell proliferation and the alloantigen-driven mixed leukocyte reaction of pooled peripheral blood mononuclear cells in a dose-dependent manner. Phytohemagglutinin-stimulated T-cell proliferation was inhibited by MSC-derived EVs in a dose-dependent manner comparable to MSCs. In contrast, inhibition of alloantigen-driven mixed leukocyte reaction was only observed for MSCs, but not for EVs. Our results support the application of a cell-based in vitro potency assay for reproducibly determining the immunomodulatory potential of EVs. Validation of this assay can help establish reliable release criteria for EVs for future clinical studies.

  15. Cancerous epithelial cell lines shed extracellular vesicles with a bimodal size distribution that is sensitive to glutamine inhibition

    International Nuclear Information System (INIS)

    Santana, Steven Michael; Kirby, Brian J; Antonyak, Marc A; Cerione, Richard A

    2014-01-01

    Extracellular shed vesicles (ESVs) facilitate a unique mode of cell–cell communication wherein vesicle uptake can induce a change in the recipient cell's state. Despite the intensity of ESV research, currently reported data represent the bulk characterization of concentrated vesicle samples with little attention paid to heterogeneity. ESV populations likely represent diversity in mechanisms of formation, cargo and size. To better understand ESV subpopulations and the signaling cascades implicated in their formation, we characterize ESV size distributions to identify subpopulations in normal and cancerous epithelial cells. We have discovered that cancer cells exhibit bimodal ESV distributions, one small-diameter and another large-diameter population, suggesting that two mechanisms may govern ESV formation, an exosome population and a cancer-specific microvesicle population. Altered glutamine metabolism in cancer is thought to fuel cancer growth but may also support metastatic niche formation through microvesicle production. We describe the role of a glutaminase inhibitor, compound 968, in ESV production. We have discovered that inhibiting glutamine metabolism significantly impairs large-diameter microvesicle production in cancer cells. (paper)

  16. Skip Regulates TGF-β1-Induced Extracellular Matrix Degrading Proteases Expression in Human PC-3 Prostate Cancer Cells

    Directory of Open Access Journals (Sweden)

    Victor Villar

    2013-01-01

    Full Text Available Purpose. To determine whether Ski-interacting protein (SKIP regulates TGF-β1-stimulated expression of urokinase-type plasminogen activator (uPA, matrix metalloproteinase-9 (MMP-9, and uPA Inhibitor (PAI-1 in the androgen-independent human prostate cancer cell model. Materials and Methods. PC-3 prostate cancer cell line was used. The role of SKIP was evaluated using synthetic small interference RNA (siRNA compounds. The expression of uPA, MMP-9, and PAI-1 was evaluated by zymography assays, RT-PCR, and promoter transactivation analysis. Results. In PC-3 cells TGF-β1 treatment stimulated uPA, PAI-1, and MMP-9 expressions. The knockdown of SKIP in PC-3 cells enhanced the basal level of uPA, and TGF-β1 treatment inhibited uPA production. Both PAI-1 and MMP-9 production levels were increased in response to TGF-β1. The ectopic expression of SKIP inhibited both TGF-β1-induced uPA and MMP-9 promoter transactivation, while PAI-1 promoter response to the factor was unaffected. Conclusions. SKIP regulates the expression of uPA, PAI-1, and MMP-9 stimulated by TGF-β1 in PC-3 cells. Thus, SKIP is implicated in the regulation of extracellular matrix degradation and can therefore be suggested as a novel therapeutic target in prostate cancer treatment.

  17. Mesenchymal stem cells use extracellular vesicles to outsource mitophagy and shuttle microRNAs

    OpenAIRE

    Phinney, Donald G.; Di Giuseppe, Michelangelo; Njah, Joel; Sala, Ernest; Shiva, Sruti; St Croix, Claudette M.; Stolz, Donna B.; Watkins, Simon C.; Di, Y. Peter; Leikauf, George D.; Kolls, Jay; Riches, David W. H.; Deiuliis, Giuseppe; Kaminski, Naftali; Boregowda, Siddaraju V.

    2015-01-01

    Mesenchymal stem cells (MSCs) and macrophages are fundamental components of the stem cell niche and function coordinately to regulate haematopoietic stem cell self-renewal and mobilization. Recent studies indicate that mitophagy and healthy mitochondrial function are critical to the survival of stem cells, but how these processes are regulated in MSCs is unknown. Here we show that MSCs manage intracellular oxidative stress by targeting depolarized mitochondria to the plasma membrane via arres...

  18. Anatomical region-dependent enhancement of 3-dimensional chondrogenic differentiation of human mesenchymal stem cells by soluble meniscus extracellular matrix.

    Science.gov (United States)

    Rothrauff, Benjamin B; Shimomura, Kazunori; Gottardi, Riccardo; Alexander, Peter G; Tuan, Rocky S

    2017-02-01

    Extracellular matrix (ECM) derived from decellularized tissues has been found to promote tissue neogenesis, most likely mediated by specific biochemical and physical signaling motifs that promote tissue-specific differentiation of progenitor cells. Decellularized ECM has been suggested to be efficacious for the repair of tissue injuries. However, decellularized meniscus contains a dense collagenous structure, which impedes cell seeding and infiltration and is not readily applicable for meniscus repair. In addition, the meniscus consists of two distinct anatomical regions that differ in vascularity and cellular phenotype. The purpose of this study was to explore the region-specific bioactivity of solubilized ECM derived from the inner and outer meniscal regions as determined in 2D and 3D cultures of adult mesenchymal stem cells (MSCs). When added as a medium supplement to 2D cultures of MSCs, urea-extracted fractions of the inner (imECM) and outer meniscal ECM (omECM) enhanced cell proliferation while imECM most strongly upregulated fibrochondrogenic differentiation on the basis of gene expression profiles. When added to 3D cultures of MSCs seeded in photocrosslinked methacrylated gelatin (GelMA) hydrogels, both ECM fractions upregulated chondrogenic differentiation as determined by gene expression and protein analyses, as well as elevated sulfated glycosaminoglycan sGAG content, compared to ECM-free controls. The chondrogenic effect at day 21 was most pronounced with imECM supplementation, but equivalent between ECM groups by day 42. Despite increased cartilage matrix, imECM and omECM constructs possessed compressive moduli similar to controls. In conclusion, soluble meniscal ECM may be considered for use as a tissue-specific reagent to enhance chondrogenesis for MSC-based 3D cartilage tissue engineering. The inner region of the knee meniscus is frequently injured and possesses a poor intrinsic healing capacity. Solubilized extracellular matrix (ECM) derived from

  19. Tenascin-C in the extracellular matrix promotes the selection of highly proliferative and tubulogenesis-defective endothelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Alves, Tercia Rodrigues [Universidade do Estado do Rio de Janeiro (UERJ), Instituto de Biologia Roberto Alcantara Gomes, Departamento de Biologia Celular, Laboratorio de Biologia da Celula Endotelial e da Angiogenese (LabAngio), Rio de Janeiro (Brazil); Universidade Federal do Rio de Janeiro (UFRJ), Programa de Biologia Celular e do Desenvolvimento, Instituto de Ciencias Biomedicas, INNT/INCT/MCT, Rio de Janeiro (Brazil); Carvalho da Fonseca, Anna Carolina [Universidade Federal do Rio de Janeiro (UFRJ), Programa de Biologia Celular e do Desenvolvimento, Instituto de Ciencias Biomedicas, INNT/INCT/MCT, Rio de Janeiro (Brazil); Nunes, Sara Santana; Oliveira da Silva, Aline [Universidade do Estado do Rio de Janeiro (UERJ), Instituto de Biologia Roberto Alcantara Gomes, Departamento de Biologia Celular, Laboratorio de Biologia da Celula Endotelial e da Angiogenese (LabAngio), Rio de Janeiro (Brazil); Dubois, Luiz Gustavo Feijo; Faria, Jane; Kahn, Suzana Assad [Universidade Federal do Rio de Janeiro (UFRJ), Programa de Biologia Celular e do Desenvolvimento, Instituto de Ciencias Biomedicas, INNT/INCT/MCT, Rio de Janeiro (Brazil); Viana, Nathan Bessa [Universidade Federal do Rio de Janeiro, Laboratorio de Pincas Oticas, Coordenacao de Programas de Estudos Avancados, Instituto de Ciencias Biomedicas, Rio de Janeiro (Brazil); Universidade Federal do Rio de Janeiro, Instituto de Fisica, Rio de Janeiro (Brazil); Marcondes, Jorge [Universidade Federal do Rio de Janeiro, Hospital Universitario Clementino Fraga Filho, Servico de Neurocirurgia, Rio de Janeiro (Brazil); Legrand, Chantal [Institut Universitaire d' Hematologie, Universite Paris-Diderot, Paris 7, INSERM U553, Paris (France); Moura-Neto, Vivaldo [Universidade Federal do Rio de Janeiro (UFRJ), Programa de Biologia Celular e do Desenvolvimento, Instituto de Ciencias Biomedicas, INNT/INCT/MCT, Rio de Janeiro (Brazil); and others

    2011-09-10

    The extracellular matrix (ECM) contains important cues for tissue homeostasis and morphogenesis. The matricellular protein tenascin-C (TN-C) is overexpressed in remodeling tissues and cancer. In the present work, we studied the effect of different ECM-which exhibited a significant diversity in their TN-C content-in endothelial survival, proliferation and tubulogenic differentiation: autologous (endothelial) ECM devoid of TN-C, but bearing large amounts of FN; fibroblast ECM, bearing both high TN-C and FN contents; and finally, glioma-derived matrices, usually poor in FN, but very rich in TN-C. HUVECs initially adhered to the immobilized matrix produced by U373 MG glioma cells, but significantly detached and died by anoikis (50 to 80%) after 24 h, as compared with cells incubated with endothelial and fibroblast matrices. Surviving endothelial cells (20 to 50%) became up to 6-fold more proliferative and formed 74-97% less tube-like structures in vitro than cells grown on non-tumoral matrices. An antibody against the EGF-like repeats of tenascin-C (TN-C) partially rescued cells from the tubulogenic defect, indicating that this molecule is responsible for the selection of highly proliferative and tubulogenic defective endothelial cells. Interestingly, by using defined substrata, in conditions that mimic glioma and normal cell ECM composition, we observed that fibronectin (FN) modulates the TN-C-induced selection of endothelial cells. Our data show that TN-C is able to modulate endothelial branching morphogenesis in vitro and, since it is prevalent in matrices of injured and tumor tissues, also suggest a role for this protein in vascular morphogenesis, in these physiological contexts.

  20. Tenascin-C in the extracellular matrix promotes the selection of highly proliferative and tubulogenesis-defective endothelial cells

    International Nuclear Information System (INIS)

    Alves, Tercia Rodrigues; Carvalho da Fonseca, Anna Carolina; Nunes, Sara Santana; Oliveira da Silva, Aline; Dubois, Luiz Gustavo Feijo; Faria, Jane; Kahn, Suzana Assad; Viana, Nathan Bessa; Marcondes, Jorge; Legrand, Chantal; Moura-Neto, Vivaldo

    2011-01-01

    The extracellular matrix (ECM) contains important cues for tissue homeostasis and morphogenesis. The matricellular protein tenascin-C (TN-C) is overexpressed in remodeling tissues and cancer. In the present work, we studied the effect of different ECM-which exhibited a significant diversity in their TN-C content-in endothelial survival, proliferation and tubulogenic differentiation: autologous (endothelial) ECM devoid of TN-C, but bearing large amounts of FN; fibroblast ECM, bearing both high TN-C and FN contents; and finally, glioma-derived matrices, usually poor in FN, but very rich in TN-C. HUVECs initially adhered to the immobilized matrix produced by U373 MG glioma cells, but significantly detached and died by anoikis (50 to 80%) after 24 h, as compared with cells incubated with endothelial and fibroblast matrices. Surviving endothelial cells (20 to 50%) became up to 6-fold more proliferative and formed 74-97% less tube-like structures in vitro than cells grown on non-tumoral matrices. An antibody against the EGF-like repeats of tenascin-C (TN-C) partially rescued cells from the tubulogenic defect, indicating that this molecule is responsible for the selection of highly proliferative and tubulogenic defective endothelial cells. Interestingly, by using defined substrata, in conditions that mimic glioma and normal cell ECM composition, we observed that fibronectin (FN) modulates the TN-C-induced selection of endothelial cells. Our data show that TN-C is able to modulate endothelial branching morphogenesis in vitro and, since it is prevalent in matrices of injured and tumor tissues, also suggest a role for this protein in vascular morphogenesis, in these physiological contexts.

  1. Non-linear elasticity of extracellular matrices enables contractile cells to communicate local position and orientation.

    Directory of Open Access Journals (Sweden)

    Jessamine P Winer

    2009-07-01

    Full Text Available Most tissue cells grown in sparse cultures on linearly elastic substrates typically display a small, round phenotype on soft substrates and become increasingly spread as the modulus of the substrate increases until their spread area reaches a maximum value. As cell density increases, individual cells retain the same stiffness-dependent differences unless they are very close or in molecular contact. On nonlinear strain-stiffening fibrin gels, the same cell types become maximally spread even when the low strain elastic modulus would predict a round morphology, and cells are influenced by the presence of neighbors hundreds of microns away. Time lapse microscopy reveals that fibroblasts and human mesenchymal stem cells on fibrin deform the substrate by several microns up to five cell lengths away from their plasma membrane through a force limited mechanism. Atomic force microscopy and rheology confirm that these strains locally and globally stiffen the gel, depending on cell density, and this effect leads to long distance cell-cell communication and alignment. Thus cells are acutely responsive to the nonlinear elasticity of their substrates and can manipulate this rheological property to induce patterning.

  2. Recapitulation of Extracellular LAMININ Environment Maintains Stemness of Satellite Cells In Vitro.

    Science.gov (United States)

    Ishii, Kana; Sakurai, Hidetoshi; Suzuki, Nobuharu; Mabuchi, Yo; Sekiya, Ichiro; Sekiguchi, Kiyotoshi; Akazawa, Chihiro

    2018-02-13

    Satellite cells function as precursor cells in mature skeletal muscle homeostasis and regeneration. In healthy tissue, these cells are maintained in a state of quiescence by a microenvironment formed by myofibers and basement membrane in which LAMININs (LMs) form a major component. In the present study, we evaluated the satellite cell microenvironment in vivo and found that these cells are encapsulated by LMα2-5. We sought to recapitulate this satellite cell niche in vitro by culturing satellite cells in the presence of recombinant LM-E8 fragments. We show that treatment with LM-E8 promotes proliferation of satellite cells in an undifferentiated state, through reduced phosphorylation of JNK and p38. On transplantation into injured muscle tissue, satellite cells cultured with LM-E8 promoted the regeneration of skeletal muscle. These findings represent an efficient method of culturing satellite cells for use in transplantation through the recapitulation of the satellite cell niche using recombinant LM-E8 fragments. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  3. Extracellular S100A4(mts1) stimulates invasive growth of mouse endothelial cells and modulates MMP-13 matrix metalloproteinase activity

    DEFF Research Database (Denmark)

    Schmidt-Hansen, Birgitte; Ornås, Dorte; Grigorian, Mariam

    2004-01-01

    with the transcriptional modulation of genes involved in the proteolytic degradation of extracellular matrix (ECM). Treatment of SVEC 4-10 with the S100A4 protein leads to the transcriptional activation of collagenase 3 (MMP-13) mRNA followed by subsequent release of the protein from the cells. Beta-casein zymography...... demonstrates enhancement of proteolytic activity associated with MMP-13. This observation indicates that extracellular S100A4 stimulates the production of ECM degrading enzymes from endothelial cells, thereby stimulating the remodeling of ECM. This could explain the angiogenic and metastasis...

  4. Comparison of four decontamination treatments on porcine renal decellularized extracellular matrix structure, composition, and support of human renal cortical tubular epithelium cells.

    Science.gov (United States)

    Poornejad, Nafiseh; Nielsen, Jeffery J; Morris, Ryan J; Gassman, Jason R; Reynolds, Paul R; Roeder, Beverly L; Cook, Alonzo D

    2016-03-01

    Engineering whole organs from porcine decellularized extracellular matrix and human cells may lead to a plentiful source of implantable organs. Decontaminating the porcine decellularized extracellular matrix scaffolds is an essential step prior to introducing human cells. However, decontamination of whole porcine kidneys is a major challenge because the decontamination agent or irradiation needs to diffuse deep into the structure to eliminate all microbial contamination while minimizing damage to the structure and composition of the decellularized extracellular matrix. In this study, we compared four decontamination treatments that could be applicable to whole porcine kidneys: 70% ethanol, 0.2% peracetic acid in 1 M NaCl, 0.2% peracetic acid in 4% ethanol, and gamma (γ)-irradiation. Porcine kidneys were decellularized by perfusion of 0.5% (w/v) aqueous solution of sodium dodecyl sulfate and the four decontamination treatments were optimized using segments (n = 60) of renal tissue to ensure a consistent comparison. Although all four methods were successful in decontamination, γ-irradiation was very damaging to collagen fibers and glycosaminoglycans, leading to less proliferation of human renal cortical tubular epithelium cells within the porcine decellularized extracellular matrix. The effectiveness of the other three optimized solution treatments were then all confirmed using whole decellularized porcine kidneys (n = 3). An aqueous solution of 0.2% peracetic acid in 1 M NaCl was determined to be the best method for decontamination of porcine decellularized extracellular matrix. © The Author(s) 2015.

  5. Abiotic factors in colony formation: effects of nutrition and light on extracellular polysaccharide production and cell aggregates of Microcystis aeruginosa

    Science.gov (United States)

    Yang, Zhen; Kong, Fanxiang

    2013-07-01

    Colony morphology is important for Microcystis to sustain a competitive advantage in eutrophic lakes. The mechanism of colony formation in Microcystis is currently unclear. Extracellular polysaccharide (EPS) has been reported to play an important role in cell aggregate formation of some phytoplankton. Microcystis aeruginosa was cultivated under varied abiotic conditions, including different nutrient, light, and temperature conditions, to investigate their effects on EPS production and morphological change. The results show that nutrient concentration and light intensity have great effects on EPS productionin M. aeruginosa. There was a considerable increase in EPS production after M. aeruginosa was cultivated in adjusted culture conditions similar to those present in the field (28.9 mg C/L, 1.98 mg N/L, 0.65 mg P/L, light intensity: 100 μmol/(m2 · s)). These results indicate that abiotic factors might be one of the triggers for colony formation in Microcystis.

  6. Measurement of the Extracellular pH of Adherently Growing Mammalian Cells with High Spatial Resolution Using a Voltammetric pH Microsensor.

    Science.gov (United States)

    Munteanu, Raluca-Elena; Stǎnicǎ, Luciana; Gheorghiu, Mihaela; Gáspár, Szilveszter

    2018-05-15

    There are only a few tools suitable for measuring the extracellular pH of adherently growing mammalian cells with high spatial resolution, and none of them is widely used in laboratories around the world. Cell biologists very often limit themselves to measuring the intracellular pH with commercially available fluorescent probes. Therefore, we built a voltammetric pH microsensor and investigated its suitability for monitoring the extracellular pH of adherently growing mammalian cells. The voltammetric pH microsensor consisted of a 37 μm diameter carbon fiber microelectrode modified with reduced graphene oxide and syringaldazine. While graphene oxide was used to increase the electrochemically active surface area of our sensor, syringaldazine facilitated pH sensing through its pH-dependent electrochemical oxidation and reduction. The good sensitivity (60 ± 2.5 mV/pH unit), reproducibility (coefficient of variation ≤3% for the same pH measured with 5 different microsensors), and stability (pH drift around 0.05 units in 3 h) of the built voltammetric pH sensors were successfully used to investigate the acidification of the extracellular space of both cancer cells and normal cells. The results indicate that the developed pH microsensor and the perfected experimental protocol based on scanning electrochemical microscopy can reveal details of the pH regulation of cells not attainable with pH sensors lacking spatial resolution or which cannot be reproducibly positioned in the extracellular space.

  7. Influence of exercise and aging on extracellular matrix composition in the skeletal muscle stem cell niche.

    Science.gov (United States)

    Garg, Koyal; Boppart, Marni D

    2016-11-01

    Skeletal muscle is endowed with a remarkable capacity for regeneration, primarily due to the reserve pool of muscle resident satellite cells. The satellite cell is the physiologically quiescent muscle stem cell that resides beneath the basal lamina and adjacent to the sarcolemma. The anatomic location of satellite cells is in close proximity to vasculature where they interact with other muscle resident stem/stromal cells (e.g., mesenchymal stem cells and pericytes) through paracrine mechanisms. This mini-review describes the components of the muscle stem cell niche, as well as the influence of exercise and aging on the muscle stem cell niche. Although exercise promotes ECM reorganization and stem cell accumulation, aging is associated with dense ECM deposition and loss of stem cell function resulting in reduced regenerative capacity and strength. An improved understanding of the niche elements will be valuable to inform the development of therapeutic interventions aimed at improving skeletal muscle regeneration and adaptation over the life span. Copyright © 2016 the American Physiological Society.

  8. Gravity loading induces adenosine triphosphate release and phosphorylation of extracellular signal-regulated kinases in human periodontal ligament cells.

    Science.gov (United States)

    Ito, Mai; Arakawa, Toshiya; Okayama, Miki; Shitara, Akiko; Mizoguchi, Itaru; Takuma, Taishin

    2014-11-01

    The periodontal ligament (PDL) receives mechanical stress (MS) from dental occlusion or orthodontic tooth movement. Mechanical stress is thought to be a trigger for remodeling of the PDL and alveolar bone, although its signaling mechanism is still unclear. So we investigated the effect of MS on adenosine triphosphate (ATP) release and extracellular signal-regulated kinases (ERK) phosphorylation in PDL cells. Mechanical stress was applied to human PDL cells as centrifugation-mediated gravity loading. Apyrase, Ca(2+)-free medium and purinergic receptor agonists and antagonists were utilized to analyze the contribution of purinergic receptors to ERK phosphorylation. Gravity loading and ATP increased ERK phosphorylation by 5 and 2.5 times, respectively. Gravity loading induced ATP release from PDL cells by tenfold. Apyrase and suramin diminished ERK phosphorylation induced by both gravity loading and ATP. Under Ca(2+)-free conditions the phosphorylation by gravity loading was partially decreased, whereas ATP-induced phosphorylation was unaffected. Receptors P2Y4 and P2Y6 were prominently expressed in the PDL cells. Gravity loading induced ATP release and ERK phosphorylation in PDL fibroblasts, and ATP signaling via P2Y receptors was partially involved in this phosphorylation, which in turn would enhance gene expression for the remodeling of PDL tissue during orthodontic tooth movement. © 2013 Wiley Publishing Asia Pty Ltd.

  9. Cathepsin B is up-regulated and mediates extracellular matrix degradation in trabecular meshwork cells following phagocytic challenge.

    Directory of Open Access Journals (Sweden)

    Kristine Porter

    Full Text Available Cells in the trabecular meshwork (TM, a tissue responsible for draining aqueous humor out of the eye, are known to be highly phagocytic. Phagocytic activity in TM cells is thought to play an important role in outflow pathway physiology. However, the molecular mechanisms triggered by phagocytosis in TM cells are unknown. Here we investigated the effects of chronic phagocytic stress on lysosomal function using different phagocytic ligands (E. coli, carboxylated beads, collagen I-coated beads, and pigment. Lysotracker red co-localization and electron micrographs showed the maturation of E. coli- and collagen I-coated beads-containing phagosomes into phagolysosomes. Maturation of phagosomes into phagolysosomes was not observed with carboxylated beads or pigment particles. In addition, phagocytosis of E. coli and collagen I-coated beads led to increased lysosomal mass, and the specific up-regulation and activity of cathepsin B (CTSB. Higher levels of membrane-bound and secreted CTSB were also detected. Moreover, in vivo zymography showed the intralysosomal degradation of ECM components associated with active CTSB, as well as an overall increased gelatinolytic activity in phagocytically challenged TM cells. This increased gelatinolytic activity with phagocytosis was partially blocked with an intracellular CTSB inhibitor. Altogether, these results suggest a potential role of phagocytosis in outflow pathway tissue homeostasis through the up-regulation and/or proteolytic activation of extracellular matrix remodeling genes.

  10. The inhibitory impacts of Lactobacillus rhamnosus GG-derived extracellular vesicles on the growth of hepatic cancer cells.

    Science.gov (United States)

    Behzadi, Elham; Mahmoodzadeh Hosseini, Hamideh; Imani Fooladi, Abbas Ali

    2017-09-01

    Bacterial extracellular vesicles (EVs) have come forth into notice as possible important agent to mediate host-pathogen interactions. In this scientific research, the authors have tried to find out the effect of EVs derived from Lactobacillus rhamnosus GG (LDEVs) on the apoptosis induction in HepG2 cell line. The EVs were purified from the conditioned medium of Lactobacillus rhamnosus GG using ultrafiltration and confirmed by transmission electron microscopy (TEM). The HepG2 cells were treated with different concentrations of purified LDEVs and the cytotoxicity and their effects on the expression of bcl-2 and bax genes were assessed by the MTT assay and semi-quantitative RT-PCR, respectively. The MTT assay showed that only 100 μg/ml of LDEVs had a significant cytotoxic effect on cancer cells (p < 0.05). The apoptotic index (bax/bcl2 expression ratio) was significantly increased after treating with 50 and 100 μg/ml LDEVs (p < 0.05). Increased bax/bcl-2 ratio was led to cancer cell death. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Cell wall-anchored nuclease of Streptococcus sanguinis contributes to escape from neutrophil extracellular trap-mediated bacteriocidal activity.

    Directory of Open Access Journals (Sweden)

    Chisato Morita

    Full Text Available Streptococcus sanguinis, a member of the commensal mitis group of streptococci, is a primary colonizer of the tooth surface, and has been implicated in infectious complications including bacteremia and infective endocarditis. During disease progression, S. sanguinis may utilize various cell surface molecules to evade the host immune system to survive in blood. In the present study, we discovered a novel cell surface nuclease with a cell-wall anchor domain, termed SWAN (streptococcal wall-anchored nuclease, and investigated its contribution to bacterial resistance against the bacteriocidal activity of neutrophil extracellular traps (NETs. Recombinant SWAN protein (rSWAN digested multiple forms of DNA including NET DNA and human RNA, which required both Mg(2+ and Ca(2+ for optimum activity. Furthermore, DNase activity of S. sanguinis was detected around growing colonies on agar plates containing DNA. In-frame deletion of the swan gene mostly reduced that activity. These findings indicated that SWAN is a major nuclease displayed on the surface, which was further confirmed by immuno-detection of SWAN in the cell wall fraction. The sensitivity of S. sanguinis to NET killing was reduced by swan gene deletion. Moreover, heterologous expression of the swan gene rendered a Lactococcus lactis strain more resistant to NET killing. Our results suggest that the SWAN nuclease on the bacterial surface contributes to survival in the potential situation of S. sanguinis encountering NETs during the course of disease progression.

  12. Cell wall-anchored nuclease of Streptococcus sanguinis contributes to escape from neutrophil extracellular trap-mediated bacteriocidal activity.

    Science.gov (United States)

    Morita, Chisato; Sumioka, Ryuichi; Nakata, Masanobu; Okahashi, Nobuo; Wada, Satoshi; Yamashiro, Takashi; Hayashi, Mikako; Hamada, Shigeyuki; Sumitomo, Tomoko; Kawabata, Shigetada

    2014-01-01

    Streptococcus sanguinis, a member of the commensal mitis group of streptococci, is a primary colonizer of the tooth surface, and has been implicated in infectious complications including bacteremia and infective endocarditis. During disease progression, S. sanguinis may utilize various cell surface molecules to evade the host immune system to survive in blood. In the present study, we discovered a novel cell surface nuclease with a cell-wall anchor domain, termed SWAN (streptococcal wall-anchored nuclease), and investigated its contribution to bacterial resistance against the bacteriocidal activity of neutrophil extracellular traps (NETs). Recombinant SWAN protein (rSWAN) digested multiple forms of DNA including NET DNA and human RNA, which required both Mg(2+) and Ca(2+) for optimum activity. Furthermore, DNase activity of S. sanguinis was detected around growing colonies on agar plates containing DNA. In-frame deletion of the swan gene mostly reduced that activity. These findings indicated that SWAN is a major nuclease displayed on the surface, which was further confirmed by immuno-detection of SWAN in the cell wall fraction. The sensitivity of S. sanguinis to NET killing was reduced by swan gene deletion. Moreover, heterologous expression of the swan gene rendered a Lactococcus lactis strain more resistant to NET killing. Our results suggest that the SWAN nuclease on the bacterial surface contributes to survival in the potential situation of S. sanguinis encountering NETs during the course of disease progression.

  13. Na+ -K+ pump activity in rat peritoneal mast cells: inhibition by extracellular calcium

    DEFF Research Database (Denmark)

    Knudsen, Torben; Johansen, Torben

    1989-01-01

    1. Pure populations of rat peritoneal mast cells were used to study cellular potassium uptake. The radioactive potassium analogue, 86rubidium, was used as a tracer for potassium for measurements of the activity of the cellular potassium uptake process. 2. The ouabain-sensitive and the ouabain......-resistant potassium (86rubidium) uptake of mast cells incubated in the presence of calcium, 1 mmol l-1, were very low, 52 and 147 pmol per 10(6) cells min-1. 3. Calcium-deprivation of the cells uncovered a large capacity ouabain-sensitive potassium (86rubidium) uptake mechanism. The activity of the uptake mechanism...... was decreased by reintroduction of calcium into the cell suspension, and it was dependent on cellular energy metabolism, temperature and pH. 4. The potassium (86rubidium) uptake of mast cells incubated in a calcium-free medium occurs through an active and ouabain-sensitive mechanism that has the nature...

  14. Extracellular acidification induces connective tissue growth factor production through proton-sensing receptor OGR1 in human airway smooth muscle cells

    Energy Technology Data Exchange (ETDEWEB)

    Matsuzaki, Shinichi [Department of Medicine and Molecular Science, Gunma University Graduate School of Medicine, Maebashi 371-8511 (Japan); Ishizuka, Tamotsu, E-mail: tamotsui@showa.gunma-u.ac.jp [Department of Medicine and Molecular Science, Gunma University Graduate School of Medicine, Maebashi 371-8511 (Japan); Yamada, Hidenori; Kamide, Yosuke; Hisada, Takeshi; Ichimonji, Isao; Aoki, Haruka; Yatomi, Masakiyo [Department of Medicine and Molecular Science, Gunma University Graduate School of Medicine, Maebashi 371-8511 (Japan); Komachi, Mayumi [Laboratory of Signal Transduction, Institute for Molecular and Cellular Regulation, Gunma University, Maebashi 371-8512 (Japan); Tsurumaki, Hiroaki; Ono, Akihiro; Koga, Yasuhiko [Department of Medicine and Molecular Science, Gunma University Graduate School of Medicine, Maebashi 371-8511 (Japan); Dobashi, Kunio [Gunma University Graduate School of Health Sciences, Maebashi 371-8511 (Japan); Mogi, Chihiro; Sato, Koichi; Tomura, Hideaki [Laboratory of Signal Transduction, Institute for Molecular and Cellular Regulation, Gunma University, Maebashi 371-8512 (Japan); Mori, Masatomo [Department of Medicine and Molecular Science, Gunma University Graduate School of Medicine, Maebashi 371-8511 (Japan); Okajima, Fumikazu [Laboratory of Signal Transduction, Institute for Molecular and Cellular Regulation, Gunma University, Maebashi 371-8512 (Japan)

    2011-10-07

    Highlights: {yields} The involvement of extracellular acidification in airway remodeling was investigated. {yields} Extracellular acidification alone induced CTGF production in human ASMCs. {yields} Extracellular acidification enhanced TGF-{beta}-induced CTGF production in human ASMCs. {yields} Proton-sensing receptor OGR1 was involved in acidic pH-stimulated CTGF production. {yields} OGR1 may play an important role in airway remodeling in asthma. -- Abstract: Asthma is characterized by airway inflammation, hyper-responsiveness and remodeling. Extracellular acidification is known to be associated with severe asthma; however, the role of extracellular acidification in airway remodeling remains elusive. In the present study, the effects of acidification on the expression of connective tissue growth factor (CTGF), a critical factor involved in the formation of extracellular matrix proteins and hence airway remodeling, were examined in human airway smooth muscle cells (ASMCs). Acidic pH alone induced a substantial production of CTGF, and enhanced transforming growth factor (TGF)-{beta}-induced CTGF mRNA and protein expression. The extracellular acidic pH-induced effects were inhibited by knockdown of a proton-sensing ovarian cancer G-protein-coupled receptor (OGR1) with its specific small interfering RNA and by addition of the G{sub q/11} protein-specific inhibitor, YM-254890, or the inositol-1,4,5-trisphosphate (IP{sub 3}) receptor antagonist, 2-APB. In conclusion, extracellular acidification induces CTGF production through the OGR1/G{sub q/11} protein and inositol-1,4,5-trisphosphate-induced Ca{sup 2+} mobilization in human ASMCs.

  15. An Impermeant Ganetespib Analog Inhibits Extracellular Hsp90-Mediated Cancer Cell Migration that Involves Lysyl Oxidase 2-like Protein

    Energy Technology Data Exchange (ETDEWEB)

    McCready, Jessica [Department of Natural Sciences, Assumption College, Worcester, MA 01609 (United States); Wong, Daniel S. [Department of Developmental Molecular and Chemical Biology, Tufts University School of Medicine, Boston, MA 02111 (United States); Cell and Molecular Physiology Program, Sackler School of Graduate Biomedical Sciences, Tufts University, Boston, MA 02111 (United States); Burlison, Joseph A.; Ying, Weiwen [Synta Pharmaceuticals, Lexington, MA 02421 (United States); Jay, Daniel G., E-mail: daniel.jay@tufts.edu [Department of Developmental Molecular and Chemical Biology, Tufts University School of Medicine, Boston, MA 02111 (United States); Cell and Molecular Physiology Program, Sackler School of Graduate Biomedical Sciences, Tufts University, Boston, MA 02111 (United States)

    2014-04-30

    Extracellular Hsp90 (eHsp90) activates a number of client proteins outside of cancer cells required for migration and invasion. Therefore, eHsp90 may serve as a novel target for anti-metastatic drugs as its inhibition using impermeant Hsp90 inhibitors would not affect the numerous vital intracellular Hsp90 functions in normal cells. While some eHsp90 clients are known, it is important to establish other proteins that act outside the cell to validate eHsp90 as a drug target to limit cancer spread. Using mass spectrometry we identified two precursor proteins Galectin 3 binding protein (G3BP) and Lysyl oxidase 2-like protein (LOXL2) that associate with eHsp90 in MDA-MB231 breast cancer cell conditioned media and confirmed that LOXL2 binds to eHsp90 in immunoprecipitates. We introduce a novel impermeant Hsp90 inhibitor STA-12-7191 derived from ganetespib and show that it is markedly less toxic to cells and can inhibit cancer cell migration in a dose dependent manner. We used STA-12-7191 to test if LOXL2 and G3BP are potential eHsp90 clients. We showed that while LOXL2 can increase wound healing and compensate for STA-12-7191-mediated inhibition of wound closure, addition of G3BP had no affect on this assay. These findings support of role for LOXL2 in eHsp90 stimulated cancer cell migration and provide preliminary evidence for the use of STA-12-7191 to inhibit eHsp90 to limit cancer invasion.

  16. An Impermeant Ganetespib Analog Inhibits Extracellular Hsp90-Mediated Cancer Cell Migration that Involves Lysyl Oxidase 2-like Protein

    International Nuclear Information System (INIS)

    McCready, Jessica; Wong, Daniel S.; Burlison, Joseph A.; Ying, Weiwen; Jay, Daniel G.

    2014-01-01

    Extracellular Hsp90 (eHsp90) activates a number of client proteins outside of cancer cells required for migration and invasion. Therefore, eHsp90 may serve as a novel target for anti-metastatic drugs as its inhibition using impermeant Hsp90 inhibitors would not affect the numerous vital intracellular Hsp90 functions in normal cells. While some eHsp90 clients are known, it is important to establish other proteins that act outside the cell to validate eHsp90 as a drug target to limit cancer spread. Using mass spectrometry we identified two precursor proteins Galectin 3 binding protein (G3BP) and Lysyl oxidase 2-like protein (LOXL2) that associate with eHsp90 in MDA-MB231 breast cancer cell conditioned media and confirmed that LOXL2 binds to eHsp90 in immunoprecipitates. We introduce a novel impermeant Hsp90 inhibitor STA-12-7191 derived from ganetespib and show that it is markedly less toxic to cells and can inhibit cancer cell migration in a dose dependent manner. We used STA-12-7191 to test if LOXL2 and G3BP are potential eHsp90 clients. We showed that while LOXL2 can increase wound healing and compensate for STA-12-7191-mediated inhibition of wound closure, addition of G3BP had no affect on this assay. These findings support of role for LOXL2 in eHsp90 stimulated cancer cell migration and provide preliminary evidence for the use of STA-12-7191 to inhibit eHsp90 to limit cancer invasion

  17. Effect of chondrocyte-derived early extracellular matrix on chondrogenesis of placenta-derived mesenchymal stem cells.

    Science.gov (United States)

    Park, Yong-Beom; Seo, Sinji; Kim, Jin-A; Heo, Jin-Chul; Lim, Young-Cheol; Ha, Chul-Won

    2015-06-24

    The extracellular matrix (ECM) surrounding cells contains a variety of proteins that provide structural support and regulate cellular functions. Previous studies have shown that decellularized ECM isolated from tissues or cultured cells can be used to improve cell differentiation in tissue engineering applications. In this study we evaluated the effect of decellularized chondrocyte-derived ECM (CDECM) on the chondrogenesis of human placenta-derived mesenchymal stem cells (hPDMSCs) in a pellet culture system. After incubation with or without chondrocyte-derived ECM in chondrogenic medium for 1 or 3 weeks, the sizes and wet masses of the cell pellets were compared with untreated controls (hPDMSCs incubated in chondrogenic medium without chondrocyte-derived ECM). In addition, histologic analysis of the cell pellets (Safranin O and collagen type II staining) and quantitative reverse transcription-PCR analysis of chondrogenic markers (aggrecan, collagen type II, and SOX9) were carried out. Our results showed that the sizes and masses of hPDMSC pellets incubated with chondrocyte-derived ECM were significantly higher than those of untreated controls. Differentiation of hPDMSCs (both with and without chondrocyte-derived ECM) was confirmed by Safranin O and collagen type II staining. Chondrogenic marker expression and glycosaminoglycan (GAG) levels were significantly higher in hPDMSC pellets incubated with chondrocyte-derived ECM compared with untreated controls, especially in cells precultured with chondrocyte-derived ECM for 7 d. Taken together, these results demonstrate that chondrocyte-derived ECM enhances the chondrogenesis of hPDMSCs, and this effect is further increased by preculture with chondrocyte-derived ECM. This preculture method for hPDMSC chondrogenesis represents a promising approach for cartilage tissue engineering.

  18. 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

  19. The non-small cell lung cancer EGFR extracellular domain mutation, M277E, is oncogenic and drug-sensitive

    Directory of Open Access Journals (Sweden)

    Yu S

    2017-09-01

    Full Text Available Su Yu,1,2 Yang Zhang,1 Yunjian Pan,1 Chao Cheng,1,3 Yihua Sun,1,3 Haiquan Chen1–4 1Department of Thoracic Surgery, Fudan University Shanghai Cancer Center, Shanghai, China; 2Cancer Research Center, Fudan University Shanghai Cancer Center, Shanghai, China; 3Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China; 4Institutes of Biomedical Sciences, Fudan University, Shanghai, China Purpose: To identify novel oncogenic mutations in non-small cell lung cancer patient specimens that lack mutations in known targetable genes (“pan-negative” patients.Methods: Comprehensive mutational analyses were performed on 1,356 lung adenocarcinoma specimens. In this cohort of patients, common lung cancer oncogenic driver mutations were detected in the epidermal growth factor receptor (EGFR kinase domain, the human epidermal growth factor receptor 2 kinase domain, as well as the KRAS, BRAF, ALK, ROS1 and RET genes. A sub-cohort of pan-negative patient specimens was assayed for mutations in the EGFR extracellular domain (ECD. Additionally, EGFR mutant NIH-3T3 stable cell lines were constructed and assessed for protein content, anchorage-independent growth, and tumor formation in xenograft models to identify oncogenic mutations. BaF3 lymphocytes were also used to test sensitivities of the mutations to tyrosine kinase inhibitors.Results: In pan-negative lung adenocarcinoma cases, a novel oncogenic EGFR ECD mutation was identified (M277E. EGFR M277E mutations encoded oncoproteins that transformed NIH-3T3 cells to grow in the absence of exogenous epidermal growth factor. Transformation was further evidenced by anchorage-independent growth and tumor formation in immunocompromised xenograft mouse models. Finally, as seen in the canonical EGFR L858R mutation, the M277E mutation conferred sensitivity to both erlotinib and cetuximab in BaF3 cell lines and to erlotinib in xenograft models.Conclusion: Here, a new EGFR driver mutation, M277E

  20. First evidence of SGPL1 expression in the cell membrane silencing the extracellular S1P siren in mammary epithelial cells.

    Science.gov (United States)

    Engel, Nadja; Adamus, Anna; Frank, Marcus; Kraft, Karin; Kühn, Juliane; Müller, Petra; Nebe, Barbara; Kasten, Annika; Seitz, Guido

    2018-01-01

    The bioactive lipid sphingosine-1-phosphate (S1P) is a main regulator of cell survival, proliferation, motility, and platelet aggregation, and it is essential for angiogenesis and lymphocyte trafficking. In that S1P acts as a second messenger intra- and extracellularly, it might promote cancer progression. The main cause is found in the high S1P concentration in the blood, which encourage cancer cells to migrate through the endothelial barrier into the blood vessels. The irreversible degradation of S1P is solely caused by the sphingosine-1-phosphate lyase (SGPL1). SGPL1 overexpression reduces cancer cell migration and therefore silences the endogenous S1P siren, which promotes cancer cell attraction-the main reason for metastasis. Since our previous metabolomics studies revealed an increased SGPL1 activity in association with successful breast cancer cell treatment in vitro, we further investigated expression and localization of SGPL1. Expression analyses confirmed a very low SGPL1 expression in all breast cancer samples, regardless of their subtype. Additionally, we were able to prove a novel SGPL expression in the cytoplasm membrane of non-tumorigenic breast cells by fusing three independent methods. The general SGPL1 downregulation and the loss of the plasma membrane expression resulted in S1P dependent stimulation of migration in the breast cancer cell lines MCF-7 and BT-20. Not only S1P stimulated migration could be repressed by overexpressing the natural SGPL1 variant not but also more general migratory activity was significantly reduced. Here, for the first time, we report on the SGPL1 plasma membrane location in human, non-malignant breast epithelial cell lines silencing the extracellular S1P siren in vitro, and thereby regulating pivotal cellular functions. Loss of this plasma membrane distribution as well as low SGPL1 expression levels could be a potential prognostic marker and a viable target for therapy. Therefore, the precise role of SGPL1 for cancer

  1. Cardiac-Derived Extracellular Matrix Enhances Cardiogenic Properties of Human Cardiac Progenitor Cells

    NARCIS (Netherlands)

    Gaetani, Roberto; Yin, Christopher; Srikumar, Neha; Braden, Rebecca; Doevendans, Pieter A; Sluijter, Joost P G; Christman, Karen L

    2016-01-01

    The use of biomaterials has been demonstrated as a viable strategy to promote cell survival and cardiac repair. However, limitations on combinational cell-biomaterial therapies exist, as cellular behavior is influenced by the microenvironment and physical characteristics of the material. Among the

  2. Inflammatory stress of pancreatic beta cells drives release of extracellular heat-shock protein 90α.

    Science.gov (United States)

    Ocaña, Gail J; Pérez, Liliana; Guindon, Lynette; Deffit, Sarah N; Evans-Molina, Carmella; Thurmond, Debbie C; Blum, Janice S

    2017-06-01

    A major obstacle in predicting and preventing the development of autoimmune type 1 diabetes (T1D) in at-risk individuals is the lack of well-established early biomarkers indicative of ongoing beta cell stress during the pre-clinical phase of disease. Recently, serum levels of the α cytoplasmic isoform of heat-shock protein 90 (hsp90) were shown to be elevated in individuals with new-onset T1D. We therefore hypothesized that hsp90α could be released from beta cells in response to cellular stress and inflammation associated with the earliest stages of T1D. Here, human beta cell lines and cadaveric islets released hsp90α in response to stress induced by treatment with a combination of pro-inflammatory cytokines including interleukin-1β, tumour necrosis factor-α and interferon-γ. Mechanistically, hsp90α release was found to be driven by cytokine-induced endoplasmic reticulum stress mediated by c-Jun N-terminal kinase (JNK), a pathway that can eventually lead to beta cell apoptosis. Cytokine-induced beta cell hsp90α release and JNK activation were significantly reduced by pre-treating cells with the endoplasmic reticulum stress-mitigating chemical chaperone tauroursodeoxycholic acid. The hsp90α release by cells may therefore be a sensitive indicator of stress during inflammation and a useful tool in assessing therapeutic mitigation of cytokine-induced cell damage linked to autoimmunity. © 2017 John Wiley & Sons Ltd.

  3. Evaluation of silk biomaterials in combination with extracellular matrix coatings for bladder tissue engineering with primary and pluripotent cells.

    Science.gov (United States)

    Franck, Debra; Gil, Eun Seok; Adam, Rosalyn M; Kaplan, David L; Chung, Yeun Goo; Estrada, Carlos R; Mauney, Joshua R

    2013-01-01

    Silk-based biomaterials in combination with extracellular matrix (ECM) coatings were assessed as templates for cell-seeded bladder tissue engineering approaches. Two structurally diverse groups of silk scaffolds were produced by a gel spinning process and consisted of either smooth, compact multi-laminates (Group 1) or rough, porous lamellar-like sheets (Group 2). Scaffolds alone or coated with collagen types I or IV or fibronectin were assessed independently for their ability to support attachment, proliferation, and differentiation of primary cell lines including human bladder smooth muscle cells (SMC) and urothelial cells as well as pluripotent cell populations, such as murine embryonic stem cells (ESC) and induced pluripotent stem (iPS) cells. AlamarBlue evaluations revealed that fibronectin-coated Group 2 scaffolds promoted the highest degree of primary SMC and urothelial cell attachment in comparison to uncoated Group 2 controls and all Group 1 scaffold variants. Real time RT-PCR and immunohistochemical (IHC) analyses demonstrated that both fibronectin-coated silk groups were permissive for SMC contractile differentiation as determined by significant upregulation of α-actin and SM22α mRNA and protein expression levels following TGFβ1 stimulation. Prominent expression of epithelial differentiation markers, cytokeratins, was observed in urothelial cells cultured on both control and fibronectin-coated groups following IHC analysis. Evaluation of silk matrices for ESC and iPS cell attachment by alamarBlue showed that fibronectin-coated Group 2 scaffolds promoted the highest levels in comparison to all other scaffold formulations. In addition, real time RT-PCR and IHC analyses showed that fibronectin-coated Group 2 scaffolds facilitated ESC and iPS cell differentiation toward both urothelial and smooth muscle lineages in response to all trans retinoic acid as assessed by induction of uroplakin and contractile gene and protein expression. These results

  4. Tissue Factor-Expressing Tumor-Derived Extracellular Vesicles Activate Quiescent Endothelial Cells via Protease-Activated Receptor-1

    Directory of Open Access Journals (Sweden)

    Sara P. Y. Che

    2017-11-01

    Full Text Available Tissue factor (TF-expressing tumor-derived extracellular vesicles (EVs can promote metastasis and pre-metastatic niche formation, but the mechanisms by which this occurs remain largely unknown. We hypothesized that generation of activated factor X (FXa by TF expressed on tumor-derived EV could activate protease-activated receptors (PARs on non-activated endothelial cells to induce a pro-adhesive and pro-inflammatory phenotype. We obtained EV from TF-expressing breast (MDA-MB-231 and pancreatic (BxPC3 and Capan-1 tumor cell lines. We measured expression of E-selectin and secretion of interleukin-8 (IL-8 in human umbilical vein endothelial cells after exposure to EV and various immunologic and chemical inhibitors of TF, FXa, PAR-1, and PAR-2. After 6 h of exposure to tumor-derived EV (pretreated with factor VIIa and FX in vitro, endothelial cells upregulated E-selectin expression and secreted IL-8. These changes were decreased with an anti-TF antibody, FXa inhibitors (FPRCK and EGRCK, and PAR-1 antagonist (E5555, demonstrating that FXa generated by TF-expressing tumor-derived EV was signaling through endothelial PAR-1. Due to weak constitutive PAR-2 expression, these endothelial responses were not induced by a PAR-2 agonist peptide (SLIGKV and were not inhibited by a PAR-2 antagonist (FSLLRY after exposure to tumor-derived EV. In conclusion, we found that TF-expressing cancer-derived EVs activate quiescent endothelial cells, upregulating E-selectin and inducing IL-8 secretion through generation of FXa and cleavage of PAR-1. Conversion of resting endothelial cells to an activated phenotype by TF-expressing cancer-derived EV could promote cancer metastases.

  5. Biomimetic extracellular matrix mediated somatic stem cell differentiation: applications in dental pulp tissue regeneration

    Science.gov (United States)

    Ravindran, Sriram; George, Anne

    2015-01-01

    Dental caries is one of the most widely prevalent infectious diseases in the world. It affects more than half of the world's population. The current treatment for necrotic dental pulp tissue arising from dental caries is root canal therapy. This treatment results in loss of tooth sensitivity and vitality making it prone for secondary infections. Over the past decade, several tissue-engineering approaches have attempted regeneration of the dental pulp tissue. Although several studies have highlighted the potential of dental stem cells, none have transitioned into a clinical setting owing to limited availability of dental stem cells and the need for growth factor delivery systems. Our strategy is to utilize the intact ECM of pulp cells to drive lineage specific differentiation of bone marrow derived mesenchymal stem cells. From a clinical perspective, pulp ECM scaffolds can be generated using cell lines and patient specific somatic stem cells can be used for regeneration. Our published results have shown the feasibility of using pulp ECM scaffolds for odontogenic differentiation of non-dental mesenchymal cells. This focused review discusses the issues surrounding dental pulp tissue regeneration and the potential of our strategy to overcome these issues. PMID:25954205

  6. Activation of the Extracellular Signal-Regulated Kinase Signaling Is Critical for Human Umbilical Cord Mesenchymal Stem Cell Osteogenic Differentiation

    Directory of Open Access Journals (Sweden)

    Chen-Shuang Li

    2016-01-01

    Full Text Available Human umbilical cord mesenchymal stem cells (hUCMSCs are recognized as candidate progenitor cells for bone regeneration. However, the mechanism of hUCMSC osteogenesis remains unclear. In this study, we revealed that mitogen-activated protein kinases (MAPKs signaling is involved in hUCMSC osteogenic differentiation in vitro. Particularly, the activation of c-Jun N-terminal kinases (JNK and p38 signaling pathways maintained a consistent level in hUCMSCs through the entire 21-day osteogenic differentiation period. At the same time, the activation of extracellular signal-regulated kinases (ERK signaling significantly increased from day 5, peaked at day 9, and declined thereafter. Moreover, gene profiling of osteogenic markers, alkaline phosphatase (ALP activity measurement, and alizarin red staining demonstrated that the application of U0126, a specific inhibitor for ERK activation, completely prohibited hUCMSC osteogenic differentiation. However, when U0126 was removed from the culture at day 9, ERK activation and osteogenic differentiation of hUCMSCs were partially recovered. Together, these findings demonstrate that the activation of ERK signaling is essential for hUCMSC osteogenic differentiation, which points out the significance of ERK signaling pathway to regulate the osteogenic differentiation of hUCMSCs as an alternative cell source for bone tissue engineering.

  7. Bio-inspired configurable multiscale extracellular matrix-like structures for functional alignment and guided orientation of cells.

    Science.gov (United States)

    Bae, Won-Gyu; Kim, Jangho; Choung, Yun-Hoon; Chung, Yesol; Suh, Kahp Y; Pang, Changhyun; Chung, Jong Hoon; Jeong, Hoon Eui

    2015-11-01

    Inspired by the hierarchically organized protein fibers in extracellular matrix (ECM) as well as the physiological importance of multiscale topography, we developed a simple but robust method for the design and manipulation of precisely controllable multiscale hierarchical structures using capillary force lithography in combination with an original wrinkling technique. In this study, based on our proposed fabrication technology, we approached a conceptual platform that can mimic the hierarchically multiscale topographical and orientation cues of the ECM for controlling cell structure and function. We patterned the polyurethane acrylate-based nanotopography with various orientations on the microgrooves, which could provide multiscale topography signals of ECM to control single and multicellular morphology and orientation with precision. Using our platforms, we found that the structures and orientations of fibroblast cells were greatly influenced by the nanotopography, rather than the microtopography. We also proposed a new approach that enables the generation of native ECM having nanofibers in specific three-dimensional (3D) configurations by culturing fibroblast cells on the multiscale substrata. We suggest that our methodology could be used as efficient strategies for the design and manipulation of various functional platforms, including well-defined 3D tissue structures for advanced regenerative medicine applications. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Inhibition of host extracellular signal-regulated kinase (ERK) activation decreases new world alphavirus multiplication in infected cells

    Energy Technology Data Exchange (ETDEWEB)

    Voss, Kelsey; Amaya, Moushimi [National Center for Biodefense and Infectious Diseases, School of Systems Biology, George Mason University, 10650 Pyramid Place, Manassas, VA (United States); Mueller, Claudius [Center for Applied Proteomics and Personalized Medicine, George Mason University, 10900 University Boulevard, Manassas, VA (United States); Roberts, Brian [Leidos Health Life Sciences, 5202 Presidents Court, Suite 110, Frederick, MD (United States); Kehn-Hall, Kylene; Bailey, Charles [National Center for Biodefense and Infectious Diseases, School of Systems Biology, George Mason University, 10650 Pyramid Place, Manassas, VA (United States); Petricoin, Emanuel [Center for Applied Proteomics and Personalized Medicine, George Mason University, 10900 University Boulevard, Manassas, VA (United States); Narayanan, Aarthi, E-mail: anaraya1@gmu.edu [National Center for Biodefense and Infectious Diseases, School of Systems Biology, George Mason University, 10650 Pyramid Place, Manassas, VA (United States)

    2014-11-15

    New World alphaviruses belonging to the family Togaviridae are classified as emerging infectious agents and Category B select agents. Our study is focused on the role of the host extracellular signal-regulated kinase (ERK) in the infectious process of New World alphaviruses. Infection of human cells by Venezuelan equine encephalitis virus (VEEV) results in the activation of the ERK-signaling cascade. Inhibition of ERK1/2 by the small molecule inhibitor Ag-126 results in inhibition of viral multiplication. Ag-126-mediated inhibition of VEEV was due to potential effects on early and late stages of the infectious process. While expression of viral proteins was down-regulated in Ag-126 treated cells, we did not observe any influence of Ag-126 on the nuclear distribution of capsid. Finally, Ag-126 exerted a broad-spectrum inhibitory effect on New World alphavirus multiplication, thus indicating that the host kinase, ERK, is a broad-spectrum candidate for development of novel therapeutics against New World alphaviruses. - Highlights: • VEEV infection activated multiple components of the ERK signaling cascade. • Inhibition of ERK activation using Ag-126 inhibited VEEV multiplication. • Activation of ERK by Ceramide C6 increased infectious titers of TC-83. • Ag-126 inhibited virulent strains of all New World alphaviruses. • Ag-126 treatment increased percent survival of infected cells.

  9. Inhibition of host extracellular signal-regulated kinase (ERK) activation decreases new world alphavirus multiplication in infected cells

    International Nuclear Information System (INIS)

    Voss, Kelsey; Amaya, Moushimi; Mueller, Claudius; Roberts, Brian; Kehn-Hall, Kylene; Bailey, Charles; Petricoin, Emanuel; Narayanan, Aarthi

    2014-01-01

    New World alphaviruses belonging to the family Togaviridae are classified as emerging infectious agents and Category B select agents. Our study is focused on the role of the host extracellular signal-regulated kinase (ERK) in the infectious process of New World alphaviruses. Infection of human cells by Venezuelan equine encephalitis virus (VEEV) results in the activation of the ERK-signaling cascade. Inhibition of ERK1/2 by the small molecule inhibitor Ag-126 results in inhibition of viral multiplication. Ag-126-mediated inhibition of VEEV was due to potential effects on early and late stages of the infectious process. While expression of viral proteins was down-regulated in Ag-126 treated cells, we did not observe any influence of Ag-126 on the nuclear distribution of capsid. Finally, Ag-126 exerted a broad-spectrum inhibitory effect on New World alphavirus multiplication, thus indicating that the host kinase, ERK, is a broad-spectrum candidate for development of novel therapeutics against New World alphaviruses. - Highlights: • VEEV infection activated multiple components of the ERK signaling cascade. • Inhibition of ERK activation using Ag-126 inhibited VEEV multiplication. • Activation of ERK by Ceramide C6 increased infectious titers of TC-83. • Ag-126 inhibited virulent strains of all New World alphaviruses. • Ag-126 treatment increased percent survival of infected cells

  10. A cell wall-bound adenosine nucleosidase is involved in the salvage of extracellular ATP in Solanum tuberosum.

    Science.gov (United States)

    Riewe, David; Grosman, Lukasz; Fernie, Alisdair R; Zauber, Henrik; Wucke, Cornelia; Geigenberger, Peter

    2008-10-01

    Extracellular ATP (eATP) has recently been demonstrated to play a crucial role in plant development and growth. To investigate the fate of eATP within the apoplast, we used intact potato (Solanum tuberosum) tuber slices as an experimental system enabling access to the apoplast without interference of cytosolic contamination. (i) Incubation of intact tuber slices with ATP led to the formation of ADP, AMP, adenosine, adenine and ribose, indicating operation of apyrase, 5'-nucleotidase and nucleosidase. (ii) Measurement of apyrase, 5'-nucleotidase and nucleosidase activities in fractionated tuber tissue confirmed the apoplastic localization for apyrase and phosphatase in potato and led to the identification of a novel cell wall-bound adenosine nucleosidase activity. (iii) When intact tuber slices were incubated with saturating concentrations of adenosine, the conversion of adenosine into adenine was much higher than adenosine import into the cell, suggesting a potential bypass of adenosine import. Consistent with this, import of radiolabeled adenine into tuber slices was inhibited when ATP, ADP or AMP were added to the slices. (iv) In wild-type plants, apyrase and adenosine nucleosidase activities were found to be co-regulated, indicating functional linkage of these enzymes in a shared pathway. (v) Moreover, adenosine nucleosidase activity was reduced in transgenic lines with strongly reduced apoplastic apyrase activity. When taken together, these results suggest that a complete ATP salvage pathway is present in the apoplast of plant cells.

  11. Prediction of equibiaxial loading stress in collagen-based extracellular matrix using a three-dimensional unit cell model.

    Science.gov (United States)

    Susilo, Monica E; Bell, Brett J; Roeder, Blayne A; Voytik-Harbin, Sherry L; Kokini, Klod; Nauman, Eric A

    2013-03-01

    Mechanical signals are important factors in determining cell fate. Therefore, insights as to how mechanical signals are transferred between the cell and its surrounding three-dimensional collagen fibril network will provide a basis for designing the optimum extracellular matrix (ECM) microenvironment for tissue regeneration. Previously we described a cellular solid model to predict fibril microstructure-mechanical relationships of reconstituted collagen matrices due to unidirectional loads (Acta Biomater 2010;6:1471-86). The model consisted of representative volume elements made up of an interconnected network of flexible struts. The present study extends this work by adapting the model to account for microstructural anisotropy of the collagen fibrils and a biaxial loading environment. The model was calibrated based on uniaxial tensile data and used to predict the equibiaxial tensile stress-stretch relationship. Modifications to the model significantly improved its predictive capacity for equibiaxial loading data. With a comparable fibril length (model 5.9-8μm, measured 7.5μm) and appropriate fibril anisotropy the anisotropic model provides a better representation of the collagen fibril microstructure. Such models are important tools for tissue engineering because they facilitate prediction of microstructure-mechanical relationships for collagen matrices over a wide range of microstructures and provide a framework for predicting cell-ECM interactions. Copyright © 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  12. Pentoxifylline regulates the cellular adhesion and its allied receptors to extracellular matrix components in breast cancer cells.

    Science.gov (United States)

    Goel, Peeyush N; Gude, Rajiv P

    2014-02-01

    Pentoxifylline (PTX) is a methylxanthine derivative that improves blood flow by decreasing its viscosity. Being an inhibitor of platelet aggregation, it can thus reduce the adhesiveness of cancer cells prolonging their circulation time. This delay in forming secondary tumours makes them more prone to immunological surveillance. Recently, we have evaluated its anti-metastatic efficacy against breast cancer, using MDA-MB-231 model system. In view of this, we had ascertained the effect of PTX on adhesion of MDA-MB-231 cells to extracellular matrix components (ECM) and its allied receptors such as the integrins. PTX affected adhesion of breast cancer cells to matrigel, collagen type IV, fibronectin and laminin in a dose dependent manner. Further, PTX showed a differential effect on integrin expression profile. The experimental metastasis model using NOD-SCID mice showed lesser tumour island formation when treated with PTX compared to the control. These findings further substantiate the anti-adhesive potential of PTX in breast cancer and warrant further insights into the functional regulation. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  13. Mesenchymal stem cells use extracellular vesicles to outsource mitophagy and shuttle microRNAs

    Science.gov (United States)

    Phinney, Donald G.; Di Giuseppe, Michelangelo; Njah, Joel; Sala, Ernest; Shiva, Sruti; St Croix, Claudette M.; Stolz, Donna B.; Watkins, Simon C.; Di, Y. Peter; Leikauf, George D.; Kolls, Jay; Riches, David W. H.; Deiuliis, Giuseppe; Kaminski, Naftali; Boregowda, Siddaraju V.; McKenna, David H.; Ortiz, Luis A.

    2015-01-01

    Mesenchymal stem cells (MSCs) and macrophages are fundamental components of the stem cell niche and function coordinately to regulate haematopoietic stem cell self-renewal and mobilization. Recent studies indicate that mitophagy and healthy mitochondrial function are critical to the survival of stem cells, but how these processes are regulated in MSCs is unknown. Here we show that MSCs manage intracellular oxidative stress by targeting depolarized mitochondria to the plasma membrane via arrestin domain-containing protein 1-mediated microvesicles. The vesicles are then engulfed and re-utilized via a process involving fusion by macrophages, resulting in enhanced bioenergetics. Furthermore, we show that MSCs simultaneously shed micro RNA-containing exosomes that inhibit macrophage activation by suppressing Toll-like receptor signalling, thereby de-sensitizing macrophages to the ingested mitochondria. Collectively, these studies mechanistically link mitophagy and MSC survival with macrophage function, thereby providing a physiologically relevant context for the innate immunomodulatory activity of MSCs. PMID:26442449

  14. Mesenchymal stem cells use extracellular vesicles to outsource mitophagy and shuttle microRNAs.

    Science.gov (United States)

    Phinney, Donald G; Di Giuseppe, Michelangelo; Njah, Joel; Sala, Ernest; Shiva, Sruti; St Croix, Claudette M; Stolz, Donna B; Watkins, Simon C; Di, Y Peter; Leikauf, George D; Kolls, Jay; Riches, David W H; Deiuliis, Giuseppe; Kaminski, Naftali; Boregowda, Siddaraju V; McKenna, David H; Ortiz, Luis A

    2015-10-07

    Mesenchymal stem cells (MSCs) and macrophages are fundamental components of the stem cell niche and function coordinately to regulate haematopoietic stem cell self-renewal and mobilization. Recent studies indicate that mitophagy and healthy mitochondrial function are critical to the survival of stem cells, but how these processes are regulated in MSCs is unknown. Here we show that MSCs manage intracellular oxidative stress by targeting depolarized mitochondria to the plasma membrane via arrestin domain-containing protein 1-mediated microvesicles. The vesicles are then engulfed and re-utilized via a process involving fusion by macrophages, resulting in enhanced bioenergetics. Furthermore, we show that MSCs simultaneously shed micro RNA-containing exosomes that inhibit macrophage activation by suppressing Toll-like receptor signalling, thereby de-sensitizing macrophages to the ingested mitochondria. Collectively, these studies mechanistically link mitophagy and MSC survival with macrophage function, thereby providing a physiologically relevant context for the innate immunomodulatory activity of MSCs.

  15. Confocal Raman microscopy to monitor extracellular matrix during dental pulp stem cells differentiation

    Science.gov (United States)

    Salehi, Hamideh; Collart-Dutilleul, Pierre-Yves; Gergely, Csilla; Cuisinier, Frédéric J. G.

    2015-07-01

    Regenerative medicine brings promising applications for mesenchymal stem cells, such as dental pulp stem cells (DPSCs). Confocal Raman microscopy, a noninvasive technique, is used to study osteogenic differentiation of DPSCs. Integrated Raman intensities in the 2800 to 3000 cm-1 region (C-H stretching) and the 960 cm-1 peak (ν1 PO43-) were collected (to image cells and phosphate, respectively), and the ratio of two peaks 1660 over 1690 cm-1 (amide I bands) to measure the collagen cross-linking has been calculated. Raman spectra of DPSCs after 21 days differentiation reveal several phosphate peaks: ν1 (first stretching mode) at 960 cm-1, ν2 at 430 cm-1, and ν4 at 585 cm-1 and collagen cross-linking can also be calculated. Confocal Raman microscopy enables monitoring osteogenic differentiation in vitro and can be a credible tool for clinical stem cell based research.

  16. Extracellular vesicles mediate signaling between the aqueous humor producing and draining cells in the ocular system.

    Science.gov (United States)

    Lerner, Natalie; Avissar, Sofia; Beit-Yannai, Elie

    2017-01-01

    Canonical Wnt signaling is associated with glaucoma pathogenesis and intraocular pressure (IOP) regulation. Our goal was to gain insight into the influence of non-pigmented ciliary epithelium (NPCE)-derived exosomes on Wnt signaling by trabecular meshwork (TM) cells. The potential impact of exosomes on Wnt signaling in the ocular drainage system remains poorly understood. Exosomes isolated from media collected from cultured NPCE cells by differential ultracentrifugation were characterized by dynamic light scattering (DLS), tunable resistive pulse sensing (TRPS), and nanoparticle tracking analysis (NTA), sucrose density gradient migration and transmission electron microscopy (TEM). The cellular target specificity of the NPCE-derived exosomes was investigated by confocal microscopy-based monitoring of the uptake of DiD-labeled exosomes over time, as compared to uptake by various cell lines. Changes in Wnt protein levels in TM cells induced by NPCE exosomes were evaluated by Western blot. Exosomes derived from NPCE cells were purified and detected as small rounded 50-140 nm membrane vesicles, as defined by DLS, NTA, TRPS and TEM. Western blot analysis indicated that the nanovesicles were positive for classic exosome markers, including Tsg101 and Alix. Isolated nanoparticles were found in sucrose density fractions typical of exosomes (1.118-1.188 g/mL sucrose). Using confocal microscopy, we demonstrated time-dependent specific accumulation of the NPCE-derived exosomes in NTM cells. Other cell lines investigated hardly revealed any exosome uptake. We further showed that exosomes induced changes in Wnt signaling protein expression in the TM cells. Western blot analysis further revealed decreased phosphorylation of GKS3β and reduced β-catenin levels. Finally, we found that treatment of NTM cells with exosomes resulted in a greater than 2-fold decrease in the level of β-catenin in the cytosolic fraction. In contrast, no remarkable difference in the amount of

  17. An ATP sensitive light addressable biosensor for extracellular monitoring of single taste receptor cell.

    Science.gov (United States)

    Wu, Chunsheng; Du, Liping; Zou, Ling; Zhao, Luhang; Wang, Ping

    2012-12-01

    Adenosine triphosphate (ATP) is considered as the key neurotransmitter in taste buds for taste signal transmission and processing. Measurements of ATP secreted from single taste receptor cell (TRC) with high sensitivity and specificity are essential for investigating mechanisms underlying taste cell-to-cell communications. In this study, we presented an aptamer-based biosensor for the detection of ATP locally secreted from single TRC. ATP sensitive DNA aptamer was used as recognition element and its DNA competitor was served as signal transduction element that was covalently immobilized on the surface of light addressable potentiometric sensor (LAPS). Due to the light addressable capability of LAPS, local ATP secretion from single TRC can be detected by monitoring the working potential shifts of LAPS. The results show this biosensor can detect ATP with high sensitivity and specificity. It is demonstrated this biosensor can effectively detect the local ATP secretion from single TRC responding to tastant mixture. This biosensor could provide a promising new tool for the research of taste cell-to-cell communications as well as for the detection of local ATP secretion from other types of ATP secreting individual cells.

  18. Intracellular and extracellular adenosine triphosphate in regulation of insulin secretion from pancreatic β cells (β).

    Science.gov (United States)

    Wang, Chunjiong; Geng, Bin; Cui, Qinghua; Guan, Youfei; Yang, Jichun

    2014-03-01

    Adenosine triphosphate (ATP) synthesis and release in mitochondria play critical roles in regulating insulin secretion in pancreatic β cells. Mitochondrial dysfunction is mainly characterized by a decrease in ATP production, which is a central event in the progression of pancreatic β cell dysfunction and diabetes. ATP has been demonstrated to regulate insulin secretion via several pathways: (i) Intracellular ATP directly closes ATP-sensitive potassium channel to open L-type calcium channel, leading to an increase in free cytosolic calcium levels and exocytosis of insulin granules; (ii) A decrease in ATP production is always associated with an increase in production of reactive oxygen species, which exerts deleterious effects on pancreatic β cell survival and insulin secretion; and (iii) ATP can be co-secreted with insulin from pancreatic β cells, and the released ATP functions as an autocrine signal to modulate insulin secretory process via P2 receptors on the cell membrane. In this review, the recent findings regarding the role and mechanism of ATP synthesis and release in regulation of insulin secretion from pancreatic β cells will be summarized and discussed. © 2013 Ruijin Hospital, Shanghai Jiaotong University School of Medicine and Wiley Publishing Asia Pty Ltd.

  19. Extracellular vesicles: Exosomes, microvesicles, and friends

    NARCIS (Netherlands)

    Raposo, G.; Stoorvogel, W.|info:eu-repo/dai/nl/074352385

    2013-01-01

    Cells release into the extracellular environment diverse types of membrane vesicles of endosomal and plasma membrane origin called exosomes and microvesicles, respectively. These extracellular vesicles (EVs) represent an important mode of intercellular communication by serving as vehicles for

  20. Culturing on decellularized extracellular matrix enhances antioxidant properties of human umbilical cord-derived mesenchymal stem cells

    International Nuclear Information System (INIS)

    Liu, Xiaozhen; Zhou, Long; Chen, Xi; Liu, Tao; Pan, Guoqing; Cui, Wenguo; Li, Mao; Luo, Zong-Ping; Pei, Ming; Yang, Huilin; Gong, Yihong; He, Fan

    2016-01-01

    Human umbilical cord-derived mesenchymal stem cells (UC-MSCs) have attracted great interest in clinical application because of their regenerative potential and their lack of ethical issues. Our previous studies showed that decellularized cell-deposited extracellular matrix (ECM) provided an in vivo-mimicking microenvironment for MSCs and facilitated in vitro cell expansion. This study was conducted to analyze the cellular response of UC-MSCs when culturing on the ECM, including reactive oxygen species (ROS), intracellular antioxidative enzymes, and the resistance to exogenous oxidative stress. After decellularization, the architecture of cell-deposited ECM was characterized as nanofibrous, collagen fibrils and the matrix components were identified as type I and III collagens, fibronectin, and laminin. Compared to tissue culture polystyrene (TCPS) plates, culturing on ECM yielded a 2-fold increase of UC-MSC proliferation and improved the percentage of cells in the S phase by 2.4-fold. The levels of intracellular ROS and hydrogen peroxide (H_2O_2) in ECM-cultured cells were reduced by 41.7% and 82.9%, respectively. More importantly, ECM-cultured UC-MSCs showed enhanced expression and activity of intracellular antioxidative enzymes such as superoxide dismutase and catalase, up-regulated expression of silent information regulator type 1, and suppressed phosphorylation of p38 mitogen-activated protein kinase. Furthermore, a continuous treatment with exogenous 100 μM H_2O_2 dramatically inhibited osteogenic differentiation of UC-MSCs cultured on TCPS, but culturing on ECM retained the differentiation capacity for matrix mineralization and osteoblast-specific marker gene expression. Collectively, by providing sufficient cell amounts and enhancing antioxidant capacity, decellularized ECM can be a promising cell culture platform for in vitro expansion of UC-MSCs. - Highlights: • Decellularization preserved the architecture and components of cell-deposited ECM.

  1. Culturing on decellularized extracellular matrix enhances antioxidant properties of human umbilical cord-derived mesenchymal stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xiaozhen [School of Engineering, Sun Yat-sen University, Guangzhou 510006 (China); Zhou, Long; Chen, Xi [Orthopaedic Institute, Soochow University, Suzhou 215007 (China); Department of Orthopaedics, The First Affiliated Hospital of Soochow University, Suzhou 215006 (China); Liu, Tao [Department of Orthopaedics, The First Affiliated Hospital of Soochow University, Suzhou 215006 (China); Pan, Guoqing; Cui, Wenguo; Li, Mao; Luo, Zong-Ping [Orthopaedic Institute, Soochow University, Suzhou 215007 (China); Department of Orthopaedics, The First Affiliated Hospital of Soochow University, Suzhou 215006 (China); Pei, Ming [Stem Cell and Tissue Engineering Laboratory, Department of Orthopaedics, West Virginia University, Morgantown, WV 26506 (United States); Yang, Huilin [Orthopaedic Institute, Soochow University, Suzhou 215007 (China); Department of Orthopaedics, The First Affiliated Hospital of Soochow University, Suzhou 215006 (China); Gong, Yihong, E-mail: gongyih@mail.sysu.edu.cn [School of Engineering, Sun Yat-sen University, Guangzhou 510006 (China); He, Fan, E-mail: fanhe@suda.edu.cn [Orthopaedic Institute, Soochow University, Suzhou 215007 (China); Department of Orthopaedics, The First Affiliated Hospital of Soochow University, Suzhou 215006 (China)

    2016-04-01

    Human umbilical cord-derived mesenchymal stem cells (UC-MSCs) have attracted great interest in clinical application because of their regenerative potential and their lack of ethical issues. Our previous studies showed that decellularized cell-deposited extracellular matrix (ECM) provided an in vivo-mimicking microenvironment for MSCs and facilitated in vitro cell expansion. This study was conducted to analyze the cellular response of UC-MSCs when culturing on the ECM, including reactive oxygen species (ROS), intracellular antioxidative enzymes, and the resistance to exogenous oxidative stress. After decellularization, the architecture of cell-deposited ECM was characterized as nanofibrous, collagen fibrils and the matrix components were identified as type I and III collagens, fibronectin, and laminin. Compared to tissue culture polystyrene (TCPS) plates, culturing on ECM yielded a 2-fold increase of UC-MSC proliferation and improved the percentage of cells in the S phase by 2.4-fold. The levels of intracellular ROS and hydrogen peroxide (H{sub 2}O{sub 2}) in ECM-cultured cells were reduced by 41.7% and 82.9%, respectively. More importantly, ECM-cultured UC-MSCs showed enhanced expression and activity of intracellular antioxidative enzymes such as superoxide dismutase and catalase, up-regulated expression of silent information regulator type 1, and suppressed phosphorylation of p38 mitogen-activated protein kinase. Furthermore, a continuous treatment with exogenous 100 μM H{sub 2}O{sub 2} dramatically inhibited osteogenic differentiation of UC-MSCs cultured on TCPS, but culturing on ECM retained the differentiation capacity for matrix mineralization and osteoblast-specific marker gene expression. Collectively, by providing sufficient cell amounts and enhancing antioxidant capacity, decellularized ECM can be a promising cell culture platform for in vitro expansion of UC-MSCs. - Highlights: • Decellularization preserved the architecture and components of cell

  2. Characterization of cell surface and extracellular matrix remodeling of Azospirillum brasilense chemotaxis-like 1 signal transduction pathway mutants by atomic force microscopy.

    Science.gov (United States)

    Edwards, Amanda Nicole; Siuti, Piro; Bible, Amber N; Alexandre, Gladys; Retterer, Scott T; Doktycz, Mitchel J; Morrell-Falvey, Jennifer L

    2011-01-01

    To compete in complex microbial communities, bacteria must sense environmental changes and adjust cellular functions for optimal growth. Chemotaxis-like signal transduction pathways are implicated in the regulation of multiple behaviors in response to changes in the environment, including motility patterns, exopolysaccharide production, and cell-to-cell interactions. In Azospirillum brasilense, cell surface properties, including exopolysaccharide production, are thought to play a direct role in promoting flocculation. Recently, the Che1 chemotaxis-like pathway from A. brasilense was shown to modulate flocculation, suggesting an associated modulation of cell surface properties. Using atomic force microscopy, distinct changes in the surface morphology of flocculating A. brasilense Che1 mutant strains were detected. Whereas the wild-type strain produces a smooth mucosal extracellular matrix after 24 h, the flocculating Che1 mutant strains produce distinctive extracellular fibril structures. Further analyses using flocculation inhibition, lectin-binding assays, and comparison of lipopolysaccharides profiles suggest that the extracellular matrix differs between the cheA1 and the cheY1 mutants, despite an apparent similarity in the macroscopic floc structures. Collectively, these data indicate that disruption of the Che1 pathway is correlated with distinctive changes in the extracellular matrix, which likely result from changes in surface polysaccharides structure and/or composition. FEMS Microbiology Letters © 2010 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. No claim to original US government works.

  3. Characterization of cell surface and extracellular matrix remodeling of Azospirillum brasilense chemotaxis-like 1 signal transduction pathway mutants by atomic force microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Doktycz, Mitchel John [ORNL; Morrell-Falvey, Jennifer L [ORNL

    2011-01-01

    To compete in complex microbial communities, bacteria must sense environmental changes and adjust cellular functions for optimal growth. Chemotaxis-like signal transduction pathways are implicated in the regulation of multiple behaviors in response to changes in the environment, including motility patterns, exopolysaccharide production, and cell-to-cell interactions. In Azospirillum brasilense, cell surface properties, including exopolysaccharide production, are thought to play a direct role in promoting flocculation. Recently, the Che1 chemotaxis-like pathway from A. brasilense was shown to modulate flocculation, suggesting an associated modulation of cell surface properties. Using atomic force microscopy, distinct changes in the surface morphology of flocculating A. brasilense Che1 mutant strains were detected. Whereas the wild-type strain produces a smooth mucosal extracellular matrix after 24 h, the flocculating Che1 mutant strains produce distinctive extracellular fibril structures. Further analyses using flocculation inhibition, lectin-binding assays, and comparison of lipopolysaccharides profiles suggest that the extracellular matrix differs between the cheA1 and the cheY1 mutants, despite an apparent similarity in the macroscopic floc structures. Collectively, these data indicate that disruption of the Che1 pathway is correlated with distinctive changes in the extracellular matrix, which likely result from changes in surface polysaccharides structure and/or composition.

  4. The formation of quiescent glomerular endothelial cell monolayer in vitro is strongly dependent on the choice of extracellular matrix coating

    Energy Technology Data Exchange (ETDEWEB)

    Pajęcka, Kamilla, E-mail: kpaj@novonordisk.com [Global Research, Novo Nordisk A/S, Måløv (Denmark); Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus (Denmark); Nielsen, Malik Nygaard [Global Research, Novo Nordisk A/S, Måløv (Denmark); Hansen, Troels Krarup [Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus (Denmark); Williams, Julie M. [Global Research, Novo Nordisk A/S, Måløv (Denmark)

    2017-04-01

    Background and aims: Nephropathy involves pathophysiological changes to the glomerulus. The primary glomerular endothelial cells (GEnCs) have emerged as an important tool for studying glomerulosclerotic mechanisms and in the screening process for drug-candidates. The success of the studies is dependent on the quality of the cell model. Therefore, we set out to establish an easy, reproducible model of the quiescent endothelial monolayer with the use of commercially available extracellular matrices (ECMs). Methods: Primary hGEnCs were seeded on various ECMs. Cell adhesion was monitored by an impedance sensing system. The localization of junctional proteins was assessed by immunofluorescence and the barrier function by passage of fluorescent dextrans and magnitude of VEGF response. Results: All ECM matrices except recombinant human laminin 111 (rhLN111) supported comparable cell proliferation. Culturing hGEnCs on rhLN521, rhLN511 or fibronectin resulted in a physiologically relevant barrier to 70 kDa dextrans which was 82% tighter than that formed on collagen type IV. Furthermore, only hGEnCs cultured on rhLN521 or rhLN511 showed plasma-membrane localized zonula occludens-1 and vascular endothelial cadherin indicative of proper tight and adherens junctions (AJ). Conclusion: We recommend culturing hGEnCs on the mature glomerular basement membrane laminin - rhLN521 – which, as the only commercially available ECM, promotes all of the characteristics of the quiescent hGEnC monolayer: cobblestone morphology, well-defined AJs and physiological perm-selectivity. - Highlights: • rhLN521, rhLN511 and hFN assure physiologically relevant permeability. • rhLN521 and rhLN511 ensure best cell morphology and adherens junction formation. • Collagen IV and I based coating results in disorganized hGEnC monolayer. • Physiologically relevant ECM may lead to down-regulation of self-produced matrices.

  5. The formation of quiescent glomerular endothelial cell monolayer in vitro is strongly dependent on the choice of extracellular matrix coating

    International Nuclear Information System (INIS)

    Pajęcka, Kamilla; Nielsen, Malik Nygaard; Hansen, Troels Krarup; Williams, Julie M.

    2017-01-01

    Background and aims: Nephropathy involves pathophysiological changes to the glomerulus. The primary glomerular endothelial cells (GEnCs) have emerged as an important tool for studying glomerulosclerotic mechanisms and in the screening process for drug-candidates. The success of the studies is dependent on the quality of the cell model. Therefore, we set out to establish an easy, reproducible model of the quiescent endothelial monolayer with the use of commercially available extracellular matrices (ECMs). Methods: Primary hGEnCs were seeded on various ECMs. Cell adhesion was monitored by an impedance sensing system. The localization of junctional proteins was assessed by immunofluorescence and the barrier function by passage of fluorescent dextrans and magnitude of VEGF response. Results: All ECM matrices except recombinant human laminin 111 (rhLN111) supported comparable cell proliferation. Culturing hGEnCs on rhLN521, rhLN511 or fibronectin resulted in a physiologically relevant barrier to 70 kDa dextrans which was 82% tighter than that formed on collagen type IV. Furthermore, only hGEnCs cultured on rhLN521 or rhLN511 showed plasma-membrane localized zonula occludens-1 and vascular endothelial cadherin indicative of proper tight and adherens junctions (AJ). Conclusion: We recommend culturing hGEnCs on the mature glomerular basement membrane laminin - rhLN521 – which, as the only commercially available ECM, promotes all of the characteristics of the quiescent hGEnC monolayer: cobblestone morphology, well-defined AJs and physiological perm-selectivity. - Highlights: • rhLN521, rhLN511 and hFN assure physiologically relevant permeability. • rhLN521 and rhLN511 ensure best cell morphology and adherens junction formation. • Collagen IV and I based coating results in disorganized hGEnC monolayer. • Physiologically relevant ECM may lead to down-regulation of self-produced matrices.

  6. Chemical and enzymatic fractionation of cell walls from Fucales: insights into the structure of the extracellular matrix of brown algae.

    Science.gov (United States)

    Deniaud-Bouët, Estelle; Kervarec, Nelly; Michel, Gurvan; Tonon, Thierry; Kloareg, Bernard; Hervé, Cécile

    2014-10-01

    Brown algae are photosynthetic multicellular marine organisms evolutionarily distant from land plants, with a distinctive cell wall. They feature carbohydrates shared with plants (cellulose), animals (fucose-containing sulfated polysaccharides, FCSPs) or bacteria (alginates). How these components are organized into a three-dimensional extracellular matrix (ECM) still remains unclear. Recent molecular analysis of the corresponding biosynthetic routes points toward a complex evolutionary history that shaped the ECM structure in brown algae. Exhaustive sequential extractions and composition analyses of cell wall material from various brown algae of the order Fucales were performed. Dedicated enzymatic degradations were used to release and identify cell wall partners. This approach was complemented by systematic chromatographic analysis to study polymer interlinks further. An additional structural assessment of the sulfated fucan extracted from Himanthalia elongata was made. The data indicate that FCSPs are tightly associated with proteins and cellulose within the walls. Alginates are associated with most phenolic compounds. The sulfated fucans from H. elongata were shown to have a regular α-(1→3) backbone structure, while an alternating α-(1→3), (1→4) structure has been described in some brown algae from the order Fucales. The data provide a global snapshot of the cell wall architecture in brown algae, and contribute to the understanding of the structure-function relationships of the main cell wall components. Enzymatic cross-linking of alginates by phenols may regulate the strengthening of the wall, and sulfated polysaccharides may play a key role in the adaptation to osmotic stress. The emergence and evolution of ECM components is further discussed in relation to the evolution of multicellularity in brown algae. © The Author 2014. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please

  7. Co-culture of chondrons and mesenchymal stromal cells reduces the loss of collagen VI and improves extracellular matrix production.

    Science.gov (United States)

    Owida, H A; De Las Heras Ruiz, T; Dhillon, A; Yang, Y; Kuiper, N J

    2017-12-01

    Adult articular chondrocytes are surrounded by a pericellular matrix (PCM) to form a chondron. The PCM is rich in hyaluronan, proteoglycans, and collagen II, and it is the exclusive location of collagen VI in articular cartilage. Collagen VI anchors the chondrocyte to the PCM. It has been suggested that co-culture of chondrons with mesenchymal stromal cells (MSCs) might enhance extracellular matrix (ECM) production. This co-culture study investigates whether MSCs help to preserve the PCM and increase ECM production. Primary bovine chondrons or chondrocytes or rat MSCs were cultured alone to establish a baseline level for ECM production. A xenogeneic co-culture monolayer model using rat MSCs (20, 50, and 80%) was established. PCM maintenance and ECM production were assessed by biochemical assays, immunofluorescence, and histological staining. Co-culture of MSCs with chondrons enhanced ECM matrix production, as compared to chondrocyte or chondron only cultures. The ratio 50:50 co-culture of MSCs and chondrons resulted in the highest increase in GAG production (18.5 ± 0.54 pg/cell at day 1 and 11 ± 0.38 pg/cell at day 7 in 50:50 co-culture versus 16.8 ± 0.61 pg/cell at day 1 and 10 ± 0.45 pg/cell at day 7 in chondron monoculture). The co-culture of MSCs with chondrons appeared to decelerate the loss of the PCM as determined by collagen VI expression, whilst the expression of high-temperature requirement serine protease A1 (HtrA1) demonstrated an inverse relationship to that of the collagen VI. Together, this implies that MSCs directly or indirectly inhibited HtrA1 activity and the co-culture of MSCs with chondrons enhanced ECM synthesis and the preservation of the PCM.

  8. Stiffness of hyaluronic acid gels containing liver extracellular matrix supports human hepatocyte function and alters cell morphology.

    Science.gov (United States)

    Deegan, Daniel B; Zimmerman, Cynthia; Skardal, Aleksander; Atala, Anthony; Shupe, Thomas D

    2015-03-01

    Tissue engineering and cell based liver therapies have utilized primary hepatocytes with limited success due to the failure of hepatocytes to maintain their phenotype in vitro. In order to overcome this challenge, hyaluronic acid (HA) cell culture substrates were formulated to closely mimic the composition and stiffness of the normal liver cellular microenvironment. The stiffness of the substrate was modulated by adjusting HA hydrogel crosslinking. Additionally, the repertoire of bioactive molecules within the HA substrate was bolstered by supplementation with normal liver extracellular matrix (ECM). Primary human hepatocyte viability and phenotype were determined over a narrow physiologically relevant range of substrate stiffnesses from 600 to 4600Pa in both the presence and absence of liver ECM. Cell attachment, viability, and organization of the actin cytoskeleton improved with increased stiffness up to 4600Pa. These differences were not evident in earlier time points or substrates containing only HA. However, gene expression for the hepatocyte markers hepatocyte nuclear factor 4 alpha (HNF4α) and albumin significantly decreased on the 4600Pa stiffness at day 7 indicating that cells may not have maintained their phenotype long-term at this stiffness. Function, as measured by albumin secretion, varied with both stiffness and time in culture and peaked at day 7 at the 1200Pa stiffness, slightly below the stiffness of normal liver ECM at 3000Pa. Overall, gel stiffness affected primary human hepatocyte cell adhesion, functional marker expression, and morphological characteristics dependent on both the presence of liver ECM in gel substrates and time in culture. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Singlet oxygen treatment of tumor cells triggers extracellular singlet oxygen generation, catalase inactivation and reactivation of intercellular apoptosis-inducing signaling☆

    Science.gov (United States)

    Riethmüller, Michaela; Burger, Nils; Bauer, Georg

    2015-01-01

    Intracellular singlet oxygen generation in photofrin-loaded cells caused cell death without discrimination between nonmalignant and malignant cells. In contrast, extracellular singlet oxygen generation caused apoptosis induction selectively in tumor cells through singlet oxygen-mediated inactivation of tumor cell protective catalase and subsequent reactivation of intercellular ROS-mediated apoptosis signaling through the HOCl and the NO/peroxynitrite signaling pathway. Singlet oxygen generation by extracellular photofrin alone was, however, not sufficient for optimal direct inactivation of catalase, but needed to trigger the generation of cell-derived extracellular singlet oxygen through the interaction between H2O2 and peroxynitrite. Thereby, formation of peroxynitrous acid, generation of hydroxyl radicals and formation of perhydroxyl radicals (HO2.) through hydroxyl radical/H2O2 interaction seemed to be required as intermediate steps. This amplificatory mechanism led to the formation of singlet oxygen at a sufficiently high concentration for optimal inactivation of membrane-associated catalase. At low initial concentrations of singlet oxygen, an additional amplification step needed to be activated. It depended on singlet oxygen-dependent activation of the FAS receptor and caspase-8, followed by caspase-8-mediated enhancement of NOX activity. The biochemical mechanisms described here might be considered as promising principle for the development of novel approaches in tumor therapy that specifically direct membrane-associated catalase of tumor cells and thus utilize tumor cell-specific apoptosis-inducing ROS signaling. PMID:26225731

  10. Singlet oxygen treatment of tumor cells triggers extracellular singlet oxygen generation, catalase inactivation and reactivation of intercellular apoptosis-inducing signaling.

    Science.gov (United States)

    Riethmüller, Michaela; Burger, Nils; Bauer, Georg

    2015-12-01

    Intracellular singlet oxygen generation in photofrin-loaded cells caused cell death without discrimination between nonmalignant and malignant cells. In contrast, extracellular singlet oxygen generation caused apoptosis induction selectively in tumor cells through singlet oxygen-mediated inactivation of tumor cell protective catalase and subsequent reactivation of intercellular ROS-mediated apoptosis signaling through the HOCl and the NO/peroxynitrite signaling pathway. Singlet oxygen generation by extracellular photofrin alone was, however, not sufficient for optimal direct inactivation of catalase, but needed to trigger the generation of cell-derived extracellular singlet oxygen through the interaction between H2O2 and peroxynitrite. Thereby, formation of peroxynitrous acid, generation of hydroxyl radicals and formation of perhydroxyl radicals (HO2(.)) through hydroxyl radical/H2O2 interaction seemed to be required as intermediate steps. This amplificatory mechanism led to the formation of singlet oxygen at a sufficiently high concentration for optimal inactivation of membrane-associated catalase. At low initial concentrations of singlet oxygen, an additional amplification step needed to be activated. It depended on singlet oxygen-dependent activation of the FAS receptor and caspase-8, followed by caspase-8-mediated enhancement of NOX activity. The biochemical mechanisms described here might be considered as promising principle for the development of novel approaches in tumor therapy that specifically direct membrane-associated catalase of tumor cells and thus utilize tumor cell-specific apoptosis-inducing ROS signaling. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  11. Increased extracellular and intracellular Ca{sup 2+} lead to adipocyte accumulation in bone marrow stromal cells by different mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Hashimoto, Ryota, E-mail: hryota@juntendo.ac.jp [Department of Physiology, Juntendo University Faculty of Medicine, Hongo 2-1-1, Bunkyo-ku, Tokyo 113-8421 (Japan); Katoh, Youichi, E-mail: katoyo@juntendo-urayasu.jp [Juntendo University Faculty of International Liberal Arts, Hongo 2-1-1, Bunkyo-ku, Tokyo 113-8421 (Japan); Department of Cardiology, Juntendo University Faculty of Medicine, Hongo 2-1-1, Bunkyo-ku, Tokyo 113-8421 (Japan); Miyamoto, Yuki [Juntendo University Faculty of Health Care and Nursing, Takasu 2-5-1, Urayasu-shi, Chiba 279-0023 (Japan); Itoh, Seigo; Daida, Hiroyuki [Department of Cardiology, Juntendo University Faculty of Medicine, Hongo 2-1-1, Bunkyo-ku, Tokyo 113-8421 (Japan); Nakazato, Yuji [Center for Environmental Research, Department of Cardiology, Juntendo University Faculty of Medicine Urayasu Hospital, Tomioka 2-1-1, Urayasu-shi, Chiba 279-0022 (Japan); Okada, Takao [Department of Physiology, Juntendo University Faculty of Medicine, Hongo 2-1-1, Bunkyo-ku, Tokyo 113-8421 (Japan)

    2015-02-20

    Mesenchymal stem cells found in bone marrow stromal cells (BMSCs) are the common progenitors for both adipocyte and osteoblast. An increase in marrow adipogenesis is associated with age-related osteopenia and anemia. Both extracellular and intracellular Ca{sup 2+} ([Ca{sup 2+}]{sub o} and [Ca{sup 2+}]{sub i}) are versatile signaling molecules that are involved in the regulation of cell functions, including proliferation and differentiation. We have recently reported that upon treatment of BMSCs with insulin and dexamethasone, both high [Ca{sup 2+}]{sub o} and high [Ca{sup 2+}]{sub i} enhanced adipocyte accumulation, which suggested that increases in [Ca{sup 2+}]{sub o} caused by bone resorption may accelerate adipocyte accumulation in aging and diabetic patients. In this study, we used primary mouse BMSCs to investigate the mechanisms by which high [Ca{sup 2+}]{sub o} and high [Ca{sup 2+}]{sub i} may enhance adipocyte accumulation. In the process of adipocyte accumulation, two important keys are adipocyte differentiation and the proliferation of BMSCs, which have the potential to differentiate into adipocytes. Use of MTT assay and real-time RT-PCR revealed that high [Ca{sup 2+}]{sub i} (ionomycin)-dependent adipocyte accumulation is caused by enhanced proliferation of BMSCs but not enhanced differentiation into adipocytes. Using fura-2 fluorescence-based approaches, we showed that high [Ca{sup 2+}]{sub o} (addition of CaCl{sub 2}) leads to increases in [Ca{sup 2+}]{sub i}. Flow cytometric methods revealed that high [Ca{sup 2+}]{sub o} suppressed the phosphorylation of ERK independently of intracellular Ca{sup 2+}. The inhibition of ERK by U0126 and PD0325901 enhanced the differentiation of BMSCs into adipocytes. These data suggest that increased extracellular Ca{sup 2+} provides the differentiation of BMSCs into adipocytes by the suppression of ERK activity independently of increased intracellular Ca{sup 2+}, which results in BMSC proliferation. - Highlights:

  12. Gene and miRNA expression signature of Lewis lung carcinoma LLC1 cells in extracellular matrix enriched microenvironment

    International Nuclear Information System (INIS)

    Stankevicius, Vaidotas; Vasauskas, Gintautas; Bulotiene, Danute; Butkyte, Stase; Jarmalaite, Sonata; Rotomskis, Ricardas; Suziedelis, Kestutis

    2016-01-01

    The extracellular matrix (ECM), one of the key components of tumor microenvironment, has a tremendous impact on cancer development and highly influences tumor cell features. ECM affects vital cellular functions such as cell differentiation, migration, survival and proliferation. Gene and protein expression levels are regulated in cell-ECM interaction dependent manner as well. The rate of unsuccessful clinical trials, based on cell culture research models lacking the ECM microenvironment, indicates the need for alternative models and determines the shift to three-dimensional (3D) laminin rich ECM models, better simulating tissue organization. Recognized advantages of 3D models suggest the development of new anticancer treatment strategies. This is among the most promising directions of 3D cell cultures application. However, detailed analysis at the molecular level of 2D/3D cell cultures and tumors in vivo is still needed to elucidate cellular pathways most promising for the development of targeted therapies. In order to elucidate which biological pathways are altered during microenvironmental shift we have analyzed whole genome mRNA and miRNA expression differences in LLC1 cells cultured in 2D or 3D culture conditions. In our study we used DNA microarrays for whole genome analysis of mRNA and miRNA expression differences in LLC1 cells cultivated in 2D or 3D culture conditions. Next, we indicated the most common enriched functional categories using KEGG pathway enrichment analysis. Finally, we validated the microarray data by quantitative PCR in LLC1 cells cultured under 2D or 3D conditions or LLC1 tumors implanted in experimental animals. Microarray gene expression analysis revealed that 1884 genes and 77 miRNAs were significantly altered in LLC1 cells after 48 h cell growth under 2D and ECM based 3D cell growth conditions. Pathway enrichment results indicated metabolic pathway, MAP kinase, cell adhesion and immune response as the most significantly altered

  13. Mechanics of extracellular vesicles derived from malaria parasiteinfected Red Blood Cells

    NARCIS (Netherlands)

    Sorkin, Raya; Vorselen, Daan; Ofir-Birin, Yifat; Roos, Wouter H.; MacKintosh, Fred C.; Regev-Rudzki, Neta; Wuite, Gijs J. L.

    2016-01-01

    Malaria is a life-threatening disease caused by parasites that are transmitted through the bites of infected mosquitoes, with Plasmodium falciparum (Pf) causing the most severe form of malaria (1). Very recently it was discovered that Pf infected red blood cells (iRBC) directly transfer information

  14. The PHR Family: The Role of Extracellular Transglycosylases in Shaping Candida albicans Cells

    Directory of Open Access Journals (Sweden)

    Laura Popolo

    2017-10-01

    Full Text Available Candida albicans is an opportunistic microorganism that can become a pathogen causing mild superficial mycosis or more severe invasive infections that can be life-threatening for debilitated patients. In the etiology of invasive infections, key factors are the adaptability of C. albicans to the different niches of the human body and the transition from a yeast form to hypha. Hyphal morphology confers high adhesiveness to the host cells, as well as the ability to penetrate into organs. The cell wall plays a crucial role in the morphological changes C. albicans undergoes in response to specific environmental cues. Among the different categories of enzymes involved in the formation of the fungal cell wall, the GH72 family of transglycosylases plays an important assembly role. These enzymes cut and religate β-(1,3-glucan, the major determinant of cell shape. In C. albicans, the PHR family encodes GH72 enzymes, some of which work in specific environmental conditions. In this review, we will summarize the work from the initial discovery of PHR genes to the study of the pH-dependent expression of PHR1 and PHR2, from the characterization of the gene products to the recent findings concerning the stress response generated by the lack of GH72 activity in C. albicans hyphae.

  15. Mesenchymal Stem/Stromal Cell-Derived Extracellular Vesicles and Their Potential as Novel Immunomodulatory Therapeutic Agents

    Directory of Open Access Journals (Sweden)

    Verena Börger

    2017-07-01

    Full Text Available Extracellular vesicles (EVs, such as exosomes and microvesicles, have been identified as mediators of a newly-discovered intercellular communication system. They are essential signaling mediators in various physiological and pathophysiological processes. Depending on their origin, they fulfill different functions. EVs of mesenchymal stem/stromal cells (MSCs have been found to promote comparable therapeutic activities as MSCs themselves. In a variety of in vivo models, it has been observed that they suppress pro-inflammatory processes and reduce oxidative stress and fibrosis. By switching pro-inflammatory into tolerogenic immune responses, MSC-EVs very likely promote tissue regeneration by creating a pro-regenerative environment allowing endogenous stem and progenitor cells to successfully repair affected tissues. Accordingly, MSC-EVs provide a novel, very promising therapeutic agent, which has already been successfully applied to humans. However, the MSC-EV production process has not been standardized, yet. Indeed, a collection of different protocols has been used for the MSC-EV production, characterization and application. By focusing on kidney, heart, liver and brain injuries, we have reviewed the major outcomes of published MSC-EV in vivo studies.

  16. Breast cancer cell cyclooxygenase-2 expression alters extracellular matrix structure and function and numbers of cancer associated fibroblasts.

    Science.gov (United States)

    Krishnamachary, Balaji; Stasinopoulos, Ioannis; Kakkad, Samata; Penet, Marie-France; Jacob, Desmond; Wildes, Flonne; Mironchik, Yelena; Pathak, Arvind P; Solaiyappan, Meiyappan; Bhujwalla, Zaver M

    2017-03-14

    Cyclooxygenase-2 (COX-2) is a critically important mediator of inflammation that significantly influences tumor angiogenesis, invasion, and metastasis. We investigated the role of COX-2 expressed by triple negative breast cancer cells in altering the structure and function of the extracellular matrix (ECM). COX-2 downregulation effects on ECM structure and function were investigated using magnetic resonance imaging (MRI) and second harmonic generation (SHG) microscopy of tumors derived from triple negative MDA-MB-231 breast cancer cells, and a derived clone stably expressing a short hairpin (shRNA) molecule downregulating COX-2. MRI of albumin-GdDTPA was used to characterize macromolecular fluid transport in vivo and SHG microscopy was used to quantify collagen 1 (Col1) fiber morphology. COX-2 downregulation decreased Col1 fiber density and altered macromolecular fluid transport. Immunohistochemistry identified significantly fewer activated cancer associated fibroblasts (CAFs) in low COX-2 expressing tumors. Metastatic lung nodules established by COX-2 downregulated cells were infrequent, smaller, and contained fewer Col1 fibers.COX-2 overexpression studies were performed with tumors derived from triple negative SUM-149 breast cancer cells lentivirally transduced to overexpress COX-2. SHG microscopy identified significantly higher Col1 fiber density in COX-2 overexpressing tumors with an increase of CAFs. These data expand upon the roles of COX-2 in shaping the structure and function of the ECM in primary and metastatic tumors, and identify the potential role of COX-2 in modifying the number of CAFs in tumors that may have contributed to the altered ECM.

  17. Oxidation modifies the structure and function of the extracellular matrix generated by human coronary artery endothelial cells.

    Science.gov (United States)

    Chuang, Christine Y; Degendorfer, Georg; Hammer, Astrid; Whitelock, John M; Malle, Ernst; Davies, Michael J

    2014-04-15

    ECM (extracellular matrix) materials, such as laminin, perlecan, type IV collagen and fibronectin, play a key role in determining the structure of the arterial wall and the properties of cells that interact with the ECM. The aim of the present study was to investigate the effect of peroxynitrous acid, an oxidant generated by activated macrophages, on the structure and function of the ECM laid down by HCAECs (human coronary artery endothelial cells) in vitro and in vivo. We show that exposure of HCAEC-derived native matrix components to peroxynitrous acid (but not decomposed oxidant) at concentrations >1 μM results in a loss of antibody recognition of perlecan, collagen IV, and cell-binding sites on laminin and fibronectin. Loss of recognition was accompanied by decreased HCAEC adhesion. Real-time PCR showed up-regulation of inflammation-associated genes, including MMP7 (matrix metalloproteinase 7) and MMP13, as well as down-regulation of the laminin α2 chain, in HCAECs cultured on peroxynitrous acid-treated matrix compared with native matrix. Immunohistochemical studies provided evidence of co-localization of laminin with 3-nitrotyrosine, a biomarker of peroxynitrous acid damage, in type II-III/IV human atherosclerotic lesions, consistent with matrix damage occurring during disease development in vivo. The results of the present study suggest a mechanism through which peroxynitrous acid modifies endothelial cell-derived native ECM proteins of the arterial basement membrane in atherosclerotic lesions. These changes to ECM and particularly perlecan and laminin may be important in inducing cellular dysfunction and contribute to atherogenesis.

  18. Divergent evolution of temozolomide resistance in glioblastoma stem cells is reflected in extracellular vesicles and coupled with radiosensitization.

    Science.gov (United States)

    Garnier, Delphine; Meehan, Brian; Kislinger, Thomas; Daniel, Paul; Sinha, Ankit; Abdulkarim, Bassam; Nakano, Ichiro; Rak, Janusz

    2018-01-22

    Glioblastoma (GBM) is almost invariably fatal due to failure of standard therapy. The relapse of GBM following surgery, radiation, and systemic temozolomide (TMZ) is attributed to the ability of glioma stem cells (GSCs) to survive, evolve, and repopulate the tumor mass, events on which therapy exerts a poorly understood influence. Here we explore the molecular and cellular evolution of TMZ resistance as it emerges in vivo (xenograft models) in a series of human GSCs with either proneural (PN) or mesenchymal (MES) molecular characteristics. We observed that the initial response of GSC-initiated intracranial xenografts to TMZ is eventually replaced by refractory growth pattern. Individual tumors derived from the same isogenic GSC line expressed divergent and complex profiles of TMZ resistance markers, with a minor representation of O6-methylguanine DNA methyltransferase (MGMT) upregulation. In several independent TMZ-resistant tumors originating from MES GSCs we observed a consistent diminution of mesenchymal features, which persisted in cell culture and correlated with increased expression of Nestin, decline in transglutaminase 2 and sensitivity to radiation. The corresponding mRNA expression profiles reflective of TMZ resistance and stem cell phenotype were recapitulated in the transcriptome of exosome-like extracellular vesicles (EVs) released by GSCs into the culture medium. Intrinsic changes in the tumor-initiating cell compartment may include loss of subtype characteristics and reciprocal alterations in sensitivity to chemo- and radiation therapy. These observations suggest that exploiting therapy-induced changes in the GSC phenotype and alternating cycles of therapy may be explored to improve GBM outcomes. © The Author(s) 2017. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

  19. Increased extracellular matrix density decreases MCF10A breast cell acinus formation in 3D culture conditions.

    Science.gov (United States)

    Lance, Amanda; Yang, Chih-Chao; Swamydas, Muthulekha; Dean, Delphine; Deitch, Sandy; Burg, Karen J L; Dréau, Didier

    2016-01-01

    The extracellular matrix (ECM) contributes to the generation and dynamic of normal breast tissue, in particular to the generation of polarized acinar and ductal structures. In vitro 3D culture conditions, including variations in the composition of the ECM, have been shown to directly influence the formation and organization of acinus-like and duct-like structures. Furthermore, the density of the ECM appears to also play a role in the normal mammary tissue and tumour formation. Here we show that the density of the ECM directly influences the number, organization and function of breast acini. Briefly, non-malignant human breast MCF10A cells were incubated in increasing densities of a Matrigel®-collagen I matrix. Elastic moduli near and distant to the acinus structures were measured by atomic force microscopy, and the number of acinus structures was determined. Immunochemistry was used to investigate the expression levels of E-cadherin, laminin, matrix metalloproteinase-14 and ß-casein in MCF10A cells. The modulus of the ECM was significantly increased near the acinus structures and the number of acinus structures decreased with the increase in Matrigel-collagen I density. As evaluated by the expression of laminin, the organization of the acinus structures present was altered as the density of the ECM increased. Increases in both E-cadherin and MMP14 expression by MCF10A cells as ECM density increased were also observed. In contrast, MCF10A cells expressed lower ß-casein levels as the ECM density increased. Taken together, these observations highlight the key role of ECM density in modulating the number, organization and function of breast acini. Copyright © 2013 John Wiley & Sons, Ltd.

  20. EXTRACELLULAR MIMETICS: A COMPARATIVE EVALUATION OF CELL ENCAPSULATION UTILIZING HYDROGELS AND SCAFFOLDS

    Directory of Open Access Journals (Sweden)

    Marco Antonio Vieira Grinet

    2017-01-01

    Full Text Available An in vitro encapsulation platform utilizing hydrogels and bone matrix (BM scaffolds to investigate the effects of microenvironmental parameters on encapsulated goat mesenchymal stem cells (gMSC was presented. The base encapsulation matrix was composed of a biocompatible hydrogel formed through a photoinitiated polymerization process. Different polymer concentrations were used to compare the effects of hydrogel crosslinking density on physical properties, as well as on cell viability. The potential of BM to support the growth and differentiation of gMSC was also analyzed. Both methods were compared in order to analyze viability. Structures that better allow flow of oxygen showed more promising results, whereas BM structures require a better evaluation method for concrete results.

  1. Integrated transcriptomic and proteomic analysis of the molecular cargo of extracellular vesicles derived from porcine adipose tissue-derived mesenchymal stem cells

    OpenAIRE

    Eirin, Alfonso; Zhu, Xiang-Yang; Puranik, Amrutesh S.; Woollard, John R.; Tang, Hui; Dasari, Surendra; Lerman, Amir; van Wijnen, Andre J.; Lerman, Lilach O.

    2017-01-01

    Background Mesenchymal stromal/stem cell (MSC) transplantation is a promising therapy for tissue regeneration. Extracellular vesicles (EVs) released by MSCs act as their paracrine effectors by delivering proteins and genetic material to recipient cells. To assess how their cargo mediates biological processes that drive their therapeutic effects, we integrated miRNA, mRNA, and protein expression data of EVs from porcine adipose tissue-derived MSCs. Methods Simultaneous expression profiles of m...

  2. Structure and barrier properties of human embryonic stem cell-derived retinal pigment epithelial cells are affected by extracellular matrix protein coating.

    Science.gov (United States)

    Sorkio, Anni; Hongisto, Heidi; Kaarniranta, Kai; Uusitalo, Hannu; Juuti-Uusitalo, Kati; Skottman, Heli

    2014-02-01

    Extracellular matrix (ECM) interactions play a vital role in cell morphology, migration, proliferation, and differentiation of cells. We investigated the role of ECM proteins on the structure and function of human embryonic stem cell-derived retinal pigment epithelial (hESC-RPE) cells during their differentiation and maturation from hESCs into RPE cells in adherent differentiation cultures on several human ECM proteins found in native human Bruch's membrane, namely, collagen I, collagen IV, laminin, fibronectin, and vitronectin, as well as on commercial substrates of xeno-free CELLstart™ and Matrigel™. Cell pigmentation, expression of RPE-specific proteins, fine structure, as well as the production of basal lamina by hESC-RPE on different protein coatings were evaluated after 140 days of differentiation. The integrity of hESC-RPE epithelium and barrier properties on different coatings were investigated by measuring transepithelial resistance. All coatings supported the differentiation of hESC-RPE cells as demonstrated by early onset of cell pigmentation and further maturation to RPE monolayers after enrichment. Mature RPE phenotype was verified by RPE-specific gene and protein expression, correct epithelial polarization, and phagocytic activity. Significant differences were found in the degree of RPE cell pigmentation and tightness of epithelial barrier between different coatings. Further, the thickness of self-assembled basal lamina and secretion of the key ECM proteins found in the basement membrane of the native RPE varied between hESC-RPE cultured on compared protein coatings. In conclusion, this study shows that the cell culture substrate has a major effect on the structure and basal lamina production during the differentiation and maturation of hESC-RPE potentially influencing the success of cell integrations and survival after cell transplantation.

  3. Albumin-induced apoptosis of glomerular parietal epithelial cells is modulated by extracellular signal-regulated kinase 1/2

    Science.gov (United States)

    Ohse, Takamoto; Krofft, Ron D.; Wu, Jimmy S.; Eddy, Allison A.; Pippin, Jeffrey W.; Shankland, Stuart J.

    2012-01-01

    Background. The biological role(s) of glomerular parietal epithelial cells (PECs) is not fully understood in health or disease. Given its location, PECs are constantly exposed to low levels of filtered albumin, which is increased in nephrotic states. We tested the hypothesis that PECs internalize albumin and increased uptake results in apoptosis. Methods. Confocal microscopy of immunofluorescent staining and immunohistochemistry were used to demonstrate albumin internalization in PECs and to quantitate albumin uptake in normal mice and rats as well as experimental models of membranous nephropathy, minimal change disease/focal segmental glomerulosclerosis and protein overload nephropathy. Fluorescence-activated cell sorting analysis was performed on immortalized cultured PECs exposed to fluorescein isothiocyanate (FITC)-labeled albumin in the presence of an endosomal inhibitor or vehicle. Apoptosis was measured by Hoechst staining in cultured PECs exposed to bovine serum albumin. Levels of phosphorylated extracellular signal-regulated kinase 1 and 2 (p-ERK1/2) were restored by retroviral infection of mitogen-activated protein kinase (MEK) 1/2 and reduced by U0126 in PECs exposed to high albumin levels in culture and apoptosis measured by Hoechst staining. Results. PECs internalized albumin normally, and this was markedly increased in all of the experimental disease models (P PECs also internalize FITC-labeled albumin, which was reduced by endosomal inhibition. A consequence of increased albumin internalization was PEC apoptosis in vitro and in vivo. Candidate signaling pathways underlying these events were examined. Data showed markedly reduced levels of phosphorylated extracellular signal-regulated kinase 1 and 2 (ERK1/2) in PECs exposed to high albumin levels in nephropathy and in culture. A role for ERK1/2 in limiting albumin-induced apoptosis was shown by restoring p-ERK1/2 by retroviral infection, which reduced apoptosis in cultured PECs, while a forced

  4. FAP-overexpressing fibroblasts produce an extracellular matrix that enhances invasive velocity and directionality of pancreatic cancer cells

    International Nuclear Information System (INIS)

    Lee, Hyung-Ok; Mullins, Stefanie R; Franco-Barraza, Janusz; Valianou, Matthildi; Cukierman, Edna; Cheng, Jonathan D

    2011-01-01

    Alterations towards a permissive stromal microenvironment provide important cues for tumor growth, invasion, and metastasis. In this study, Fibroblast activation protein (FAP), a serine protease selectively produced by tumor-associated fibroblasts in over 90% of epithelial tumors, was used as a platform for studying tumor-stromal interactions. We tested the hypothesis that FAP enzymatic activity locally modifies stromal ECM (extracellular matrix) components thus facilitating the formation of a permissive microenvironment promoting tumor invasion in human pancreatic cancer. We generated a tetracycline-inducible FAP overexpressing fibroblastic cell line to synthesize an in vivo-like 3-dimensional (3D) matrix system which was utilized as a stromal landscape for studying matrix-induced cancer cell behaviors. A FAP-dependent topographical and compositional alteration of the ECM was characterized by measuring the relative orientation angles of fibronectin fibers and by Western blot analyses. The role of FAP in the matrix-induced permissive tumor behavior was assessed in Panc-1 cells in assorted matrices by time-lapse acquisition assays. Also, FAP + matrix-induced regulatory molecules in cancer cells were determined by Western blot analyses. We observed that FAP remodels the ECM through modulating protein levels, as well as through increasing levels of fibronectin and collagen fiber organization. FAP-dependent architectural/compositional alterations of the ECM promote tumor invasion along characteristic parallel fiber orientations, as demonstrated by enhanced directionality and velocity of pancreatic cancer cells on FAP + matrices. This phenotype can be reversed by inhibition of FAP enzymatic activity during matrix production resulting in the disorganization of the ECM and impeded tumor invasion. We also report that the FAP + matrix-induced tumor invasion phenotype is β 1 -integrin/FAK mediated. Cancer cell invasiveness can be affected by alterations in the tumor

  5. Investigation of extracellular microRNAs in oral squamous cell carcinoma, rheumatoid arthritis and mesenchymal stem cell differentiation

    DEFF Research Database (Denmark)

    Yan, Yan

    serve as biomarkers for human diseases and can also act as mediators in cell-cell communication. In cancer, the abnormal expression of miRNAs in plasma has been observed. However, there is no report on the association of plasma miRNA expression with oral squamous cell carcinoma (OSCC) recurrence after...

  6. Regulation of cyclic AMP by extracellular ATP in cultured brain capillary endothelial cells

    Science.gov (United States)

    Anwar, Zubeya; Albert, Jennifer L; Gubby, Sharon E; Boyle, John P; Roberts, Jonathon A; Webb, Tania E; Boarder, Michael R

    1999-01-01

    In primary unpassaged rat brain capillary endothelial cell cultures (RBECs), using reverse-transcriptase PCR with primers specific for P2Y receptor subtypes, we detected mRNA for P2Y2, P2Y4 and P2Y6, but not P2Y1 receptors.None of the various nucleotides tested reduced forskolin elevated cyclic AMP levels in RBECs. ATP and ATPγS, as well as adenosine, enhanced cyclic AMP accumulation in the presence of forskolin.Comparison of the concentration response curves to ATPγS with those for ATP and adenosine, at different incubation times, indicated that the response to purine nucleotides was not wholly dependent on conversion to adenosine. Adenosine deaminase abolished the response to adenosine but only reduced the response to ATP by about 50%. These results suggest the participation of a receptor responsive to nucleotides.Isobutylmethylxanthine and 8-sulphophenyltheophylline prevented the cyclic AMP response, while neither 8-cyclopentyl-1,3-dipropylxanthine nor SCH58261 were effective antagonists. 2-chloradenosine gave a robust response, but neither 2-chloro-N6-cyclopentyladenosine nor CGS 21680 were agonists.These results show that adenosine and ATP can elevate the cyclic AMP levels of brain endothelial cells by acting on receptors which have a pharmacology apparently distinct from known P2Y and adenosine receptors. PMID:10510459

  7. Exosomes from embryonic mesenchymal stem cells alleviate osteoarthritis through balancing synthesis and degradation of cartilage extracellular matrix.

    Science.gov (United States)

    Wang, Yafei; Yu, Dongsheng; Liu, Zhiming; Zhou, Fang; Dai, Jun; Wu, Bingbing; Zhou, Jing; Heng, Boon Chin; Zou, Xiao Hui; Ouyang, Hongwei; Liu, Hua

    2017-08-14

    Mesenchymal stem cell therapy for osteoarthritis (OA) has been widely investigated, but the mechanisms are still unclear. Exosomes that serve as carriers of genetic information have been implicated in many diseases and are known to participate in many physiological processes. Here, we investigate the therapeutic potential of exosomes from human embryonic stem cell-induced mesenchymal stem cells (ESC-MSCs) in alleviating osteoarthritis (OA). Exosomes were harvested from conditioned culture media of ESC-MSCs by a sequential centrifugation process. Primary mouse chondrocytes treated with interleukin 1 beta (IL-1β) were used as an in vitro model to evaluate the effects of the conditioned medium with or without exosomes and titrated doses of isolated exosomes for 48 hours, prior to immunocytochemistry or western blot analysis. Destabilization of the medial meniscus (DMM) surgery was performed on the knee joints of C57BL/6 J mice as an OA model. This was followed by intra-articular injection of either ESC-MSCs or their exosomes. Cartilage destruction and matrix degradation were evaluated with histological staining and OARSI scores at the post-surgery 8 weeks. We found that intra-articular injection of ESC-MSCs alleviated cartilage destruction and matrix degradation in the DMM model. Further in vitro studies illustrated that this effect was exerted through ESC-MSC-derived exosomes. These exosomes maintained the chondrocyte phenotype by increasing collagen type II synthesis and decreasing ADAMTS5 expression in the presence of IL-1β. Immunocytochemistry revealed colocalization of the exosomes and collagen type II-positive chondrocytes. Subsequent intra-articular injection of exosomes derived from ESC-MSCs successfully impeded cartilage destruction in the DMM model. The exosomes from ESC-MSCs exert a beneficial therapeutic effect on OA by balancing the synthesis and degradation of chondrocyte extracellular matrix (ECM), which in turn provides a new target for OA drug

  8. Extracellular matrix of adipogenically differentiated mesenchymal stem cells reveals a network of collagen filaments, mostly interwoven by hexagonal structural units.

    Science.gov (United States)

    Ullah, Mujib; Sittinger, Michael; Ringe, Jochen

    2013-01-01

    Extracellular matrix (ECM) is the non-cellular component of tissues, which not only provides biological shelter but also takes part in the cellular decisions for diverse functions. Every tissue has an ECM with unique composition and topology that governs the process of determination, differentiation, proliferation, migration and regeneration of cells. Little is known about the structural organization of matrix especially of MSC-derived adipogenic ECM. Here, we particularly focus on the composition and architecture of the fat ECM to understand the cellular behavior on functional bases. Thus, mesenchymal stem cells (MSC) were adipogenically differentiated, then, were transferred to adipogenic propagation medium, whereas they started the release of lipid droplets leaving bare network of ECM. Microarray analysis was performed, to indentify the molecular machinery of matrix. Adipogenesis was verified by Oil Red O staining of lipid droplets and by qPCR of adipogenic marker genes PPARG and FABP4. Antibody staining demonstrated the presence of collagen type I, II and IV filaments, while alkaline phosphatase activity verified the ossified nature of these filaments. In the adipogenic matrix, the hexagonal structures were abundant followed by octagonal structures, whereas they interwoven in a crisscross manner. Regarding molecular machinery of adipogenic ECM, the bioinformatics analysis revealed the upregulated expression of COL4A1, ITGA7, ITGA7, SDC2, ICAM3, ADAMTS9, TIMP4, GPC1, GPC4 and downregulated expression of COL14A1, ADAMTS5, TIMP2, TIMP3, BGN, LAMA3, ITGA2, ITGA4, ITGB1, ITGB8, CLDN11. Moreover, genes associated with integrins, glycoproteins, laminins, fibronectins, cadherins, selectins and linked signaling pathways were found. Knowledge of the interactive-language between cells and matrix could be beneficial for the artificial designing of biomaterials and bioscaffolds. © 2013.

  9. Fibroblast-Derived Extracellular Matrix Induces Chondrogenic Differentiation in Human Adipose-Derived Mesenchymal Stromal/Stem Cells in Vitro

    Directory of Open Access Journals (Sweden)

    Kevin Dzobo

    2016-08-01

    Full Text Available Mesenchymal stromal/stem cells (MSCs represent an area being intensively researched for tissue engineering and regenerative medicine applications. MSCs may provide the opportunity to treat diseases and injuries that currently have limited therapeutic options, as well as enhance present strategies for tissue repair. The cellular environment has a significant role in cellular development and differentiation through cell–matrix interactions. The aim of this study was to investigate the behavior of adipose-derived MSCs (ad-MSCs in the context of a cell-derived matrix so as to model the in vivo physiological microenvironment. The fibroblast-derived extracellular matrix (fd-ECM did not affect ad-MSC morphology, but reduced ad-MSC proliferation. Ad-MSCs cultured on fd-ECM displayed decreased expression of integrins α2 and β1 and subsequently lost their multipotency over time, as shown by the decrease in CD44, Octamer-binding transcription factor 4 (OCT4, SOX2, and NANOG gene expression. The fd-ECM induced chondrogenic differentiation in ad-MSCs compared to control ad-MSCs. Loss of function studies, through the use of siRNA and a mutant Notch1 construct, revealed that ECM-mediated ad-MSCs chondrogenesis requires Notch1 and β-catenin signaling. The fd-ECM also showed anti-senescence effects on ad-MSCs. The fd-ECM is a promising approach for inducing chondrogenesis in ad-MSCs and chondrogenic differentiated ad-MSCs could be used in stem cell therapy procedures.

  10. Proton receptor GPR68 expression in dendritic-cell-like S100β-positive cells of rat anterior pituitary gland: GPR68 induces interleukin-6 gene expression in extracellular acidification.

    Science.gov (United States)

    Horiguchi, Kotaro; Higuchi, Masashi; Yoshida, Saishu; Nakakura, Takashi; Tateno, Kozue; Hasegawa, Rumi; Takigami, Shu; Ohsako, Shunji; Kato, Takako; Kato, Yukio

    2014-11-01

    S100β-positive cells, which do not express the classical pituitary hormones, appear to possess multifunctional properties and are assumed to be heterogeneous in the anterior pituitary gland. The presence of several protein markers has shown that S100β-positive cells are composed of populations such as stem/progenitor cells, epithelial cells, astrocytes and dendritic cells. Recently, we succeeded in separating S100β-positive cells into round-cell (dendritic-cell-like) and process-cell types. We also found the characteristic expression of anti-inflammatory factors (interleukin-6, Il-6) and membrane receptors (integrin β-6) in the round type. Here, we further investigate the function of the subpopulation of S100β-positive cells. Since IL-6 is also a paracrine factor that regulates hormone producing-cells, we examine whether a correlation exists among extracellular acid stress, IL-6 and hormone production by using primary cultures of anterior pituitary cells. Dendritic-cell-like S100β-positive cells notably expressed Gpr68 (proton receptor) and Il-6. Furthermore, the expression of Il-6 and proopiomelanocortin (Pomc) was up-regulated by extracellular acidification. The functional role of IL-6 and GPR68 in the gene expression of Pomc during extracellular acidification was also examined. Small interfering RNA for Il-6 up-regulated Pomc expression and that for Gpr68 reversed the down-regulation of Il-6 and up-regulated Pomc expression by extracellular acidification. Thus, S100β-positive dendritic-like cells can sense an increase in extracellular protons via GPR68 and respond by the production of IL-6 in order to suppress the up-regulation of Pomc expression.

  11. Enrichment of glioma stem cell-like cells on 3D porous scaffolds composed of different extracellular matrix.

    Science.gov (United States)

    Wang, Xuanzhi; Dai, Xingliang; Zhang, Xinzhi; Li, Xinda; Xu, Tao; Lan, Qing

    2018-04-15

    Cancer stem cells (CSCs), being tumor-initiating with self-renewal capacity and heterogeneity, are most likely the cause of tumor resistance, reoccurrence and metastasis. To further investigate the role of CSCs in tumor biology, there is a need to develop an effective culture system to grow, maintain and enrich CSCs. Three-dimensional (3D) cell culture model has been widely used in tumor research and drug screening. Recently, researchers have begun to utilize 3D models to culture cancer cells for CSCs enrichment. In this study, glioma cell line was cultured with 3D porous chitosan (CS) scaffolds or chitosan-hyaluronic acid (CS-HA) scaffolds to explore the possibility of glioma stem cells (GSCs)-like cells enrichment, to study the morphology, gene expression, and in vivo tumorigenicity of 3D scaffolds cells, and to compare results to 2D controls. Results showed that glioma cells on both CS and CS-HA scaffolds could form tumor cell spheroids and increased the expression of GSCs biomarkers compared to conventional 2D monolayers. Furthermore, cells in CS-HA scaffolds had higher expression levels of epithelial-to-mesenchymal transition (EMT)-related gene. Specifically, the in vivo tumorigenicity capability of CS-HA scaffold cultured cells was greater than 2D cells or CS scaffold cultured cells. It is indicated that the chemical composition of scaffold plays an important role in the enrichment of CSCs. Our results suggest that CS-HA scaffolds have a better capability to enrich GSCs-like cells and can serve as a simple and effective way to cultivate and enrich CSCs in vitro to support the study of CSCs biology and development of novel anti-cancer therapies. Copyright © 2018 Elsevier Inc. All rights reserved.

  12. The extracellular matrix and focal adhesion kinase signaling regulate cancer stem cell function in pancreatic ductal adenocarcinoma.

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    Asma Begum

    Full Text Available Cancer stem cells (CSCs play an important role in the clonogenic growth and metastasis of pancreatic ductal adenocarcinoma (PDAC. A hallmark of PDAC is the desmoplastic reaction, but the impact of the tumor microenvironment (TME on CSCs is unknown. In order to better understand the mechanisms, we examined the impact of extracellular matrix (ECM proteins on PDAC CSCs. We quantified the effect of ECM proteins, β1-integrin, and focal adhesion kinase (FAK on clonogenic PDAC growth and migration in vitro and tumor initiation, growth, and metastasis in vivo in nude mice using shRNA and overexpression constructs as well as small molecule FAK inhibitors. Type I collagen increased PDAC tumor initiating potential, self-renewal, and the frequency of CSCs through the activation of FAK. FAK overexpression increased tumor initiation, whereas a dominant negative FAK mutant or FAK kinase inhibitors reduced clonogenic PDAC growth in vitro and in vivo. Moreover, the FAK inhibitor VS-4718 extended the anti-tumor response to gemcitabine and nab-paclitaxel in patient-derived PDAC xenografts, and the loss of FAK expression limited metastatic dissemination of orthotopic xenografts. Type I collagen enhances PDAC CSCs, and both kinase-dependent and independent activities of FAK impact PDAC tumor initiation, self-renewal, and metastasis. The anti-tumor impact of FAK inhibitors in combination with standard chemotherapy support the clinical testing of this combination.

  13. Feasibility of autologous bone marrow mesenchymal stem cell-derived extracellular matrix scaffold for cartilage tissue engineering.

    Science.gov (United States)

    Tang, Cheng; Xu, Yan; Jin, Chengzhe; Min, Byoung-Hyun; Li, Zhiyong; Pei, Xuan; Wang, Liming

    2013-12-01

    Extracellular matrix (ECM) materials are widely used in cartilage tissue engineering. However, the current ECM materials are unsatisfactory for clinical practice as most of them are derived from allogenous or xenogenous tissue. This study was designed to develop a novel autologous ECM scaffold for cartilage tissue engineering. The autologous bone marrow mesenchymal stem cell-derived ECM (aBMSC-dECM) membrane was collected and fabricated into a three-dimensional porous scaffold via cross-linking and freeze-drying techniques. Articular chondrocytes were seeded into the aBMSC-dECM scaffold and atelocollagen scaffold, respectively. An in vitro culture and an in vivo implantation in nude mice model were performed to evaluate the influence on engineered cartilage. The current results showed that the aBMSC-dECM scaffold had a good microstructure and biocompatibility. After 4 weeks in vitro culture, the engineered cartilage in the aBMSC-dECM scaffold group formed thicker cartilage tissue with more homogeneous structure and higher expressions of cartilaginous gene and protein compared with the atelocollagen scaffold group. Furthermore, the engineered cartilage based on the aBMSC-dECM scaffold showed better cartilage formation in terms of volume and homogeneity, cartilage matrix content, and compressive modulus after 3 weeks in vivo implantation. These results indicated that the aBMSC-dECM scaffold could be a successful novel candidate scaffold for cartilage tissue engineering. © 2013 Wiley Periodicals, Inc. and International Center for Artificial Organs and Transplantation.

  14. Micrococcus luteus mediated dual mode synthesis of gold nanoparticles: involvement of extracellular α-amylase and cell wall teichuronic acid.

    Science.gov (United States)

    Arunkumar, Pichaimani; Thanalakshmi, Muthukrishnan; Kumar, Priyadarsini; Premkumar, Kumpati

    2013-03-01

    In the present study we have utilized the bioreductive potential of Micrococcus luteus for the synthesis of gold nanoparticles. Biochemical and physiological analysis indicate that the biosynthesized GNPs were achieved by dual mode, involving extracellular α-amylase and cell wall teichuronic acid (TUA) of M. luteus. The biosynthetic potential of both α-amylase and TUA, after isolation from bacterium, was examined. Under optimum conditions, these biomolecules reduces Au(3+) into Au(0) and the resulting GNPs were found to be stable for 1 month. The synthesized GNPs were characterized by UV-VIS spectrometry, transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR) and dynamic light scattering (DLS). Results demonstrated that the synthesized GNPs were found to be monodispersive and spherical in shape with an average size of ∼6 nm and ∼50 nm for α-amylase and teichuronic acid, respectively. These findings suggest that M. luteus can be exploited as a potential biosource for the eco-friendly synthesis of gold nanoparticles. Copyright © 2012 Elsevier B.V. All rights reserved.

  15. Regeneration of Cartilage in Human Knee Osteoarthritis with Autologous Adipose Tissue-Derived Stem Cells and Autologous Extracellular Matrix

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    Jaewoo Pak

    2016-08-01

    Full Text Available This clinical case series demonstrates that percutaneous injections of autologous adipose tissue-derived stem cells (ADSCs and homogenized extracellular matrix (ECM in the form of adipose stromal vascular fraction (SVF, along with hyaluronic acid (HA and platelet-rich plasma (PRP activated by calcium chloride, could regenerate cartilage-like tissue in human knee osteoarthritis (OA patients. Autologous lipoaspirates were obtained from adipose tissue of the abdominal origin. Afterward, the lipoaspirates were minced to homogenize the ECM. These homogenized lipoaspirates were then mixed with collagenase and incubated. The resulting mixture of ADSCs and ECM in the form of SVF was injected, along with HA and PRP activated by calcium chloride, into knees of three Korean patients with OA. The same affected knees were reinjected weekly with additional PRP activated by calcium chloride for 3 weeks. Pretreatment and post-treatment magnetic resonance imaging (MRI data, functional rating index, range of motion (ROM, and pain score data were then analyzed. All patients' MRI data showed cartilage-like tissue regeneration. Along with MRI evidence, the measured physical therapy outcomes in terms of ROM, subjective pain, and functional status were all improved. This study demonstrates that percutaneous injection of ADSCs with ECM contained in autologous adipose SVF, in conjunction with HA and PRP activated by calcium chloride, is a safe and potentially effective minimally invasive therapy for OA of human knees.

  16. Uncovering the Role of Erythrocyte-Derived Extracellular Vesicles in Malaria: From Immune Regulation to Cell Communication

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    Johan Ankarklev

    2014-05-01

    Full Text Available Investigation of the involvement of extracellular vesicles (EVs in parasite biology has burgeoned in recent years. Human infecting protozoan parasites, such as Trypanosoma cruzi, Lesihmania sp . and Trichomonas vaginalis , have all demonstrated the utilization of EVs as virulence factors in order to activate or hamper host immunity. Novel findings have provided evidence that the deployment of EVs by Plasmodium sp . has a major impact in disease outcomes and serves as an integral part in controlling stage switching in its life cycle. Clinical studies have highlighted elevated levels of EVs in patients with severe malaria disease and EVs have been linked to increased sequestration of infected red blood cells to the endothelium, causing obstruction of blood flow. It has also been found that EVs produced during malaria disease activate innate immunity. Intriguingly, recent discoveries indicate that Plasmodium sp . “highjack” the erythrocyte microvesiculation system in order to cross-communicate. Both the transfer of DNA and parasite density regulation has been suggested as key mechanisms of EVs in malaria biology.

  17. Tumor Cell Invasion Can Be Blocked by Modulators of Collagen Fibril Alignment That Control Assembly of the Extracellular Matrix.

    Science.gov (United States)

    Grossman, Moran; Ben-Chetrit, Nir; Zhuravlev, Alina; Afik, Ran; Bassat, Elad; Solomonov, Inna; Yarden, Yosef; Sagi, Irit

    2016-07-15

    Abnormal architectures of collagen fibers in the extracellular matrix (ECM) are hallmarks of many invasive diseases, including cancer. Targeting specific stages of collagen assembly in vivo presents a great challenge due to the involvement of various crosslinking enzymes in the multistep, hierarchical process of ECM build-up. Using advanced microscopic tools, we monitored stages of fibrillary collagen assembly in a native fibroblast-derived 3D matrix system and identified anti-lysyl oxidase-like 2 (LOXL2) antibodies that alter the natural alignment and width of endogenic fibrillary collagens without affecting ECM composition. The disrupted collagen morphologies interfered with the adhesion and invasion properties of human breast cancer cells. Treatment of mice bearing breast cancer xenografts with the inhibitory antibodies resulted in disruption of the tumorigenic collagen superstructure and in reduction of primary tumor growth. Our approach could serve as a general methodology to identify novel therapeutics targeting fibrillary protein organization to treat ECM-associated pathologies. Cancer Res; 76(14); 4249-58. ©2016 AACR. ©2016 American Association for Cancer Research.

  18. First evidence of SGPL1 expression in the cell membrane silencing the extracellular S1P siren in mammary epithelial cells.

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    Nadja Engel

    Full Text Available The bioactive lipid sphingosine-1-phosphate (S1P is a main regulator of cell survival, proliferation, motility, and platelet aggregation, and it is essential for angiogenesis and lymphocyte trafficking. In that S1P acts as a second messenger intra- and extracellularly, it might promote cancer progression. The main cause is found in the high S1P concentration in the blood, which encourage cancer cells to migrate through the endothelial barrier into the blood vessels. The irreversible degradation of S1P is solely caused by the sphingosine-1-phosphate lyase (SGPL1. SGPL1 overexpression reduces cancer cell migration and therefore silences the endogenous S1P siren, which promotes cancer cell attraction-the main reason for metastasis. Since our previous metabolomics studies revealed an increased SGPL1 activity in association with successful breast cancer cell treatment in vitro, we further investigated expression and localization of SGPL1. Expression analyses confirmed a very low SGPL1 expression in all breast cancer samples, regardless of their subtype. Additionally, we were able to prove a novel SGPL expression in the cytoplasm membrane of non-tumorigenic breast cells by fusing three independent methods. The general SGPL1 downregulation and the loss of the plasma membrane expression resulted in S1P dependent stimulation of migration in the breast cancer cell lines MCF-7 and BT-20. Not only S1P stimulated migration could be repressed by overexpressing the natural SGPL1 variant not but also more general migratory activity was significantly reduced. Here, for the first time, we report on the SGPL1 plasma membrane location in human, non-malignant breast epithelial cell lines silencing the extracellular S1P siren in vitro, and thereby regulating pivotal cellular functions. Loss of this plasma membrane distribution as well as low SGPL1 expression levels could be a potential prognostic marker and a viable target for therapy. Therefore, the precise role of

  19. Differential effects of the extracellular microenvironment on human embryonic stem cell differentiation into keratinocytes and their subsequent replicative life span.

    Science.gov (United States)

    Movahednia, Mohammad Mehdi; Kidwai, Fahad Karim; Zou, Yu; Tong, Huei Jinn; Liu, Xiaochen; Islam, Intekhab; Toh, Wei Seong; Raghunath, Michael; Cao, Tong

    2015-04-01

    Culture microenvironment plays a critical role in the propagation and differentiation of human embryonic stem cells (hESCs) and their differentiated progenies. Although high efficiency of hESC differentiation to keratinocytes (hESC-Kert) has been achieved, little is known regarding the effects of early culture microenvironment and pertinent extracellular matrix (ECM) interactions during epidermal commitment on subsequent proliferative capacity of hESC-Kert. The aim of this study is to evaluate the effects of the different ECM microenvironments during hESC differentiation on subsequent replicative life span of hESC-Kert. In doing so, H1-hESCs were differentiated to keratinocytes (H1-Kert) in two differentiation systems. The first system employed autologous fibroblast feeder support, in which keratinocytes (H1-Kert(ACC)) were derived by coculture of hESCs with hESC-derived fibroblasts (H1-ebFs). The second system employed a novel decellularized matrix from H1-ebFs to create a dermoepidermal junction-like (DEJ) matrix. H1-Kert(AFF) were derived by differentiation of hESCs on the feeder-free system employing the DEJ matrix. Our study indicated that the feeder-free system with the use of DEJ matrix was more efficient in differentiation of hESCs toward epidermal progenitors. However, the feeder-free system was not sufficient to support the subsequent replicative capacity of differentiated keratinocytes. Of note, H1-Kert(AFF) showed limited replicative capacity with reduced telomere length and early cellular senescence. We further showed that the lack of cell-cell interactions during epidermal commitment led to heightened production of TGF-β1 by hESC-Kert during extended culture, which in turn was responsible for resulting in the limited replicative life span with cellular senescence of hESC-Kert derived under the feeder-free culture system. This study highlights for the first time the importance of the culture microenvironment and cell-ECM interactions during

  20. Region-Specific Effect of the Decellularized Meniscus Extracellular Matrix on Mesenchymal Stem Cell-Based Meniscus Tissue Engineering.

    Science.gov (United States)

    Shimomura, Kazunori; Rothrauff, Benjamin B; Tuan, Rocky S

    2017-03-01

    The meniscus is the most commonly injured knee structure, and surgical repair is often ineffective. Tissue engineering-based repair or regeneration may provide a needed solution. Decellularized, tissue-derived extracellular matrices (ECMs) have received attention for their potential use as tissue-engineered scaffolds. In considering meniscus-derived ECMs (mECMs) for meniscus tissue engineering, it is noteworthy that the inner and outer regions of the meniscus have different structural and biochemical features, potentially directing the differentiation of cells toward region-specific phenotypes. To investigate the applicability of mECMs for meniscus tissue engineering by specifically comparing region-dependent effects of mECMs on 3-dimensional constructs seeded with human bone marrow mesenchymal stem cells (hBMSCs). Controlled laboratory study. Bovine menisci were divided into inner and outer halves and were minced, treated with Triton X-100 and DNase, and extracted with urea. Then, hBMSCs (1 × 10 6 cells/mL) were encapsulated in a photo-cross-linked 10% polyethylene glycol diacrylate scaffold containing mECMs (60 μg/mL) derived from either the inner or outer meniscus, with an ECM-free scaffold as a control. The cell-seeded constructs were cultured with chondrogenic medium containing recombinant human transforming growth factor β3 (TGF-β3) and were analyzed for expression of meniscus-associated genes as well as for the collagen (hydroxyproline) and glycosaminoglycan content as a function of time. Decellularization was verified by the absence of 4',6-diamidino-2-phenylindole (DAPI)-stained cell nuclei and a reduction in the DNA content. Quantitative real-time polymerase chain reaction showed that collagen type I expression was significantly higher in the outer mECM group than in the other groups, while collagen type II and aggrecan expression was highest in the inner mECM group. The collagen (hydroxyproline) content was highest in the outer mECM group, while the

  1. Transforming growth factor beta 1 modulates extracellular matrix organization and cell-cell junctional complex formation during in vitro angiogenesis.

    Science.gov (United States)

    Merwin, J R; Anderson, J M; Kocher, O; Van Itallie, C M; Madri, J A

    1990-01-01

    Transforming growth factor-beta 1 (TGF-beta 1) is angiogenic in vivo. In two-dimensional (2-D) culture systems microvascular endothelial cell proliferation is inhibited up to 80% by TGF-beta 1; however, in three-dimensional (3-D) collagen gels TGF-beta 1 is found to have no effect on proliferation while eliciting the formation of calcium and magnesium dependent tube-like structures mimicking angiogenesis. DNA analyses performed on 3-D cell cultures reveal no significant difference in the amount of DNA or cell number in control versus TGF-beta 1 treated cultures. In 2-D cultures TGF-beta 1 is known to increase cellular fibronectin accumulation; however, in 3-D cultures no difference is seen between control and TGF-beta 1 treated cells as established by ELISA testing for type IV collagen, fibronectin, and laminin. In 3-D cultures there is increased synthesis and secretion of type V collagen in both control and TGF-beta 1 treated cultures over 2-D cultures. Even though an equal amount of type V collagen is seen in both 3-D conditions, there is a reorganization of the protein with concentration along an organizing basal lamina in TGF-beta 1 treated cultures. EM morphological analyses on 3-D cultures illustrate quiescent, control cells lacking cell contacts. In contrast, TGF-beta 1 treated cells show increased pseudopod formation, cell-cell contact, and organized basal lamina-like material closely apposed to the "abluminal" plasma membranes. TGF-beta 1 treated cells also appear to form junctional complexes between adjoining cells. Immunofluorescence using specific antibodies to the tight junction protein ZO-1 results in staining at apparent cell-cell junctions in the 3-D cultures. Northern blots of freshly isolated microvascular endothelium, 2-D and 3-D cultures, using cDNA and cRNA probes specific for the ZO-1 tight junction protein, reveal the presence of the 7.8 kb mRNA. Western blots of rat epididymal fat pad endothelial cells (RFC) monolayer lysates probed with

  2. Cell-secreted extracellular matrix formation and differentiation of adipose-derived stem cells in 3D alginate scaffolds with tunable properties.

    Science.gov (United States)

    Guneta, Vipra; Loh, Qiu Li; Choong, Cleo

    2016-05-01

    Three dimensional (3D) alginate scaffolds with tunable mechanical and structural properties are explored for investigating the effect of the scaffold properties on stem cell behavior and extracellular matrix (ECM) formation. Varying concentrations of crosslinker (20 - 60%) are used to tune the stiffness, porosity, and the pore sizes of the scaffolds post-fabrication. Enhanced cell proliferation and adipogenesis occur in scaffolds with 3.52 ± 0.59 kPa stiffness, 87.54 ± 18.33% porosity and 68.33 ± 0.88 μm pore size. On the other hand, cells in scaffolds with stiffness greater than 11.61 ± 1.74 kPa, porosity less than 71.98 ± 6.25%, and pore size less than 64.15 ± 4.34 μm preferentially undergo osteogenesis. When cultured in differentiation media, adipose-derived stem cells (ASCs) undergoing terminal adipogenesis in 20% firming buffer (FB) scaffolds and osteogenesis in 40% and 60% FB scaffolds show the highest secretion of collagen as compared to other groups of scaffolds. Overall, this study demonstrates the three-way relationship between 3D scaffolds, ECM composition, and stem cell differentiation. © 2016 Wiley Periodicals, Inc.

  3. Non-coding RNAs in Mesenchymal Stem Cell-Derived Extracellular Vesicles: Deciphering Regulatory Roles in Stem Cell Potency, Inflammatory Resolve, and Tissue Regeneration

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    Farah Fatima

    2017-10-01

    Full Text Available Extracellular vesicles (EVs are heterogeneous populations of nano- and micro-sized vesicles secreted by various cell types. There is mounting evidence that EVs have widespread roles in transporting proteins, lipids, and nucleic acids between cells and serve as mediators of intercellular communication. EVs secreted from stem cells could function as paracrine factors, and appear to mimic and recapitulate several features of their secreting cells. EV-mediated transport of regulatory RNAs provides a novel source of trans-regulation between cells. As such, stem cells have evolved unique forms of paracrine mechanisms for recapitulating their potencies with specialized functions by transporting non-coding RNAs (ncRNAs via EVs. This includes the dissemination of stem cell-derived EV-ncRNAs and their regulatory effects elicited in differentiation, self-renewal, pluripotency, and the induction of reparative programs. Here, we summarize and discuss the therapeutic effects of mesenchymal stem cell-derived EV-ncRNAs in the induction of intrinsic regenerative programs elicited through regulating several mechanisms. Among them, most noticeable are the EV-mediated enrichment of ncRNAs at the injury sites contributing the regulation of matrix remodeling, epithelial mesenchymal transitions, and attraction of fibroblasts. Additionally, we emphasize EV-mediated transmission of anti-inflammatory RNAs from stem cells to injury site that potentially orchestrate the resolution of the inflammatory responses and immune alleviation to better facilitate healing processes. Collectively, this knowledge indicates a high value and potential of EV-mediated RNA-based therapeutic approaches in regenerative medicine.

  4. α2 Integrin, extracellular matrix metalloproteinase inducer, and matrix metalloproteinase-3 act sequentially to induce differentiation of mouse embryonic stem cells into odontoblast-like cells

    International Nuclear Information System (INIS)

    Ozeki, Nobuaki; Kawai, Rie; Hase, Naoko; Hiyama, Taiki; Yamaguchi, Hideyuki; Kondo, Ayami; Nakata, Kazuhiko; Mogi, Makio

    2015-01-01

    We previously reported that interleukin 1β acts via matrix metalloproteinase (MMP)-3 to regulate cell proliferation and suppress apoptosis in α2 integrin-positive odontoblast-like cells differentiated from mouse embryonic stem (ES) cells. Here we characterize the signal cascade underpinning odontoblastic differentiation in mouse ES cells. The expression of α2 integrin, extracellular matrix metalloproteinase inducer (Emmprin), and MMP-3 mRNA and protein were all potently increased during odontoblastic differentiation. Small interfering RNA (siRNA) disruption of the expression of these effectors potently suppressed the expression of the odontoblastic biomarkers dentin sialophosphoprotein, dentin matrix protein-1 and alkaline phosphatase, and blocked odontoblast calcification. Our siRNA, western blot and blocking antibody analyses revealed a unique sequential cascade involving α2 integrin, Emmprin and MMP-3 that drives ES cell differentiation into odontoblasts. This cascade requires the interaction between α2 integrin and Emmprin and is potentiated by exogenous MMP-3. Finally, although odontoblast-like cells potently express α2, α6, αV, β1, and β3, integrins, we confirmed that β1 integrin acts as the trigger for ES cell differentiation, apparently in complex with α2 integrin. These results demonstrate a unique and unanticipated role for an α2 integrin-, Emmprin-, and MMP-3-mediated signaling cascade in driving mouse ES cell differentiation into odontoblast-like cells. - Highlights: • Odontoblast differentiation requires activation of α2 integrin, Emmprin and MMP-3. • α2 integrin, Emmprin and MMP-3 form a sequential signaling cascade. • β1 integrin acts a specific trigger for odontoblast differentiation. • The role of these effectors is highly novel and unanticipated

  5. α2 Integrin, extracellular matrix metalloproteinase inducer, and matrix metalloproteinase-3 act sequentially to induce differentiation of mouse embryonic stem cells into odontoblast-like cells

    Energy Technology Data Exchange (ETDEWEB)

    Ozeki, Nobuaki; Kawai, Rie; Hase, Naoko; Hiyama, Taiki; Yamaguchi, Hideyuki [Department of Endodontics, School of Dentistry, Aichi Gakuin University, Nagoya, Aichi 464-8651 (Japan); Kondo, Ayami [Department of Medicinal Biochemistry, School of Pharmacy, Aichi Gakuin University, Nagoya 464-8650 (Japan); Nakata, Kazuhiko [Department of Endodontics, School of Dentistry, Aichi Gakuin University, Nagoya, Aichi 464-8651 (Japan); Mogi, Makio, E-mail: makio@dpc.agu.ac.jp [Department of Medicinal Biochemistry, School of Pharmacy, Aichi Gakuin University, Nagoya 464-8650 (Japan)

    2015-02-01

    We previously reported that interleukin 1β acts via matrix metalloproteinase (MMP)-3 to regulate cell proliferation and suppress apoptosis in α2 integrin-positive odontoblast-like cells differentiated from mouse embryonic stem (ES) cells. Here we characterize the signal cascade underpinning odontoblastic differentiation in mouse ES cells. The expression of α2 integrin, extracellular matrix metalloproteinase inducer (Emmprin), and MMP-3 mRNA and protein were all potently increased during odontoblastic differentiation. Small interfering RNA (siRNA) disruption of the expression of these effectors potently suppressed the expression of the odontoblastic biomarkers dentin sialophosphoprotein, dentin matrix protein-1 and alkaline phosphatase, and blocked odontoblast calcification. Our siRNA, western blot and blocking antibody analyses revealed a unique sequential cascade involving α2 integrin, Emmprin and MMP-3 that drives ES cell differentiation into odontoblasts. This cascade requires the interaction between α2 integrin and Emmprin and is potentiated by exogenous MMP-3. Finally, although odontoblast-like cells potently express α2, α6, αV, β1, and β3, integrins, we confirmed that β1 integrin acts as the trigger for ES cell differentiation, apparently in complex with α2 integrin. These results demonstrate a unique and unanticipated role for an α2 integrin-, Emmprin-, and MMP-3-mediated signaling cascade in driving mouse ES cell differentiation into odontoblast-like cells. - Highlights: • Odontoblast differentiation requires activation of α2 integrin, Emmprin and MMP-3. • α2 integrin, Emmprin and MMP-3 form a sequential signaling cascade. • β1 integrin acts a specific trigger for odontoblast differentiation. • The role of these effectors is highly novel and unanticipated.

  6. 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

  7. Development of a three-dimensional unit cell to model the micromechanical response of a collagen-based extracellular matrix.

    Science.gov (United States)

    Susilo, Monica E; Roeder, Blayne A; Voytik-Harbin, Sherry L; Kokini, Klod; Nauman, Eric A

    2010-04-01

    The three-dimensional microstructure and mechanical properties of the collagen fibrils within the extracellular matrix (ECM) is now being recognized as a primary factor in regulating cell proliferation and differentiation. Therefore, an appreciation of the mechanical aspects by which a cell interacts with its ECM is required for the development of engineered tissues. Ultimately, using these interactions to design tissue equivalents requires mathematical models with three-dimensional architecture. In this study, a three-dimensional model of a collagen fibril matrix undergoing uniaxial tensile stress was developed by making use of cellular solids. A structure consisting of thin struts was chosen to represent the arrangement of collagen fibrils within an engineered ECM. To account for the large deformation of tissues, the collagen fibrils were modeled as hyperelastic neo-Hookean or Mooney-Rivlin materials. The use of cellular solids allowed the fibril properties to be related to the ECM properties in closed form, which, in turn, allowed the estimation of fibril properties using ECM experimental data. A set of previously obtained experimental data consisting of simultaneous measures of the fibril microstructure and mechanical tests was used to evaluate the model's capability to estimate collagen fibril mechanical property when given tissue-scale data and to predict the tissue-scale mechanical properties when given estimated fibril stiffness. The fibril tangent modulus was found to be 1.26 + or - 0.70 and 1.62 + or - 0.88 MPa when the fibril was modeled as neo-Hookean and Mooney-Rivlin material, respectively. There was no statistical significance of the estimated fibril tangent modulus among the different groups. Sensitivity analysis showed that the fibril mechanical properties and volume fraction were the two input parameters which required accurate values. While the volume fraction was easily obtained from the initial image of the gel, the fibril mechanical properties

  8. Effects of 42 deg. C hyperthermia on intracellular pH in ovarian carcinoma cells during acute or chronic exposure to low extracellular pH

    International Nuclear Information System (INIS)

    Wahl, Miriam L.; Bobyock, Suzanne B.; Leeper, Dennis B.; Owen, Charles S.

    1997-01-01

    Purpose: To determine whether intracellular pH (pH i ) is affected during hyperthermia in substrate-attached cells and whether acute extracellular acidification potentiates the cytotoxicity of hyperthermia via an effect on pH i . Methods and Materials: The pH i was determined in cells attached to extracellular matrix proteins loaded with the fluorescent indicator dye BCECF at 37 deg. C and during 42 deg. C hyperthermia at an extracellular pH (pH e ) of 6.7 or 7.3 in cells. Effects on pH i during hyperthermia are compared to effects on clonogenic survival after hyperthermia at pH e 7.3 and 6.7 of cells grown at pH e 7.3, or of cells grown and monitored at pH e 6.7. Results: The results show that pH i values are affected by substrate attachments. Cells attached to extracellular matrix proteins had better signal stability, low dye leakage and evidence of homeostatic regulation of pH i during heating. The net decrease in pH i in cells grown and assayed at pH e = 7.3 during 42 deg. C hyperthermia was 0.28 units and the decrease in low pH adapted cells heated at pH e = 6.7 was 0.14 units. Acute acidification from pH e = 7.3 to pH e = 6.7 at 37 deg. C caused an initial reduction of 0.5-0.8 unit in pH i , but a partial recovery followed during the next 60-90 min. Concurrent 42 deg. C hyperthermia caused the same initial reduction in pH i in acutely acidified cells, but inhibited the partial recovery that occurred during the next 60-90 min at 37 deg. C. After 4 h at 37 deg. C, the net change in pH i in acutely acidified cells was 0.30 pH unit, but at 42 deg. C is 0.63 pH units. The net change in pH i correlated inversely with clonogenic survival. Conclusions: Hyperthermia causes a pH i reduction in cells which was smaller in magnitude by 50% in low pH adapted cells. Hyperthermia inhibited the partial recovery from acute acidification that was observed at 37 deg. C in substrate attached cells, in parallel with a lower subsequent clonogenic survival

  9. Interleukin-1β regulates cell proliferation and activity of extracellular matrix remodelling enzymes in cultured primary pig heart cells

    International Nuclear Information System (INIS)

    Zitta, Karina; Brandt, Berenice; Wuensch, Annegret; Meybohm, Patrick; Bein, Berthold; Steinfath, Markus; Scholz, Jens; Albrecht, Martin

    2010-01-01

    Research highlights: → Levels of IL-1β are increased in the pig myocardium after infarction. → Cultured pig heart cells possess IL-1 receptors. → IL-1β increases cell proliferation of pig heart cells in-vitro. → IL-1β increases MMP-2 and MMP-9 activity in pig heart cells in-vitro. → IL-1β may be important for tissue remodelling events after myocardial infarction. -- Abstract: After myocardial infarction, elevated levels of interleukins (ILs) are found within the myocardial tissue and IL-1β is considered to play a major role in tissue remodelling events throughout the body. In the study presented, we have established a cell culture model of primary pig heart cells to evaluate the effects of different concentrations of IL-1β on cell proliferation as well as expression and activity of enzymes typically involved in tissue remodelling. Primary pig heart cell cultures were derived from three different animals and stimulated with recombinant pig IL-1β. RNA expression was detected by RT-PCR, protein levels were evaluated by Western blotting, activity of matrix metalloproteinases (MMPs) was quantified by gelatine zymography and cell proliferation was measured using colorimetric MTS assays. Pig heart cells express receptors for IL-1 and application of IL-1β resulted in a dose-dependent increase of cell proliferation (P < 0.05 vs. control; 100 ng/ml; 24 h). Gene expression of caspase-3 was increased by IL-1β (P < 0.05 vs. control; 100 ng/ml; 3 h), and pro-caspase-3 but not active caspase was detected in lysates of pig heart cells by Western blotting. MMP-2 gene expression as well as enzymatic activities of MMP-2 and MMP-9 were increased by IL-1β (P < 0.05 vs. control; 100 ng/ml; 3 h for gene expression, 48 and 72 h for enzymatic activities of MMP-2 and MMP-9, respectively). Our in vitro data suggest that IL-1β plays a major role in the events of tissue remodelling in the heart. Combined with our recently published in vivo data (Meybohm et al., PLoS One

  10. Interleukin-1{beta} regulates cell proliferation and activity of extracellular matrix remodelling enzymes in cultured primary pig heart cells

    Energy Technology Data Exchange (ETDEWEB)

    Zitta, Karina; Brandt, Berenice [Department of Anesthesiology and Intensive Care Medicine, University Hospital Schleswig-Holstein, Campus Kiel (Germany); Wuensch, Annegret [Institute of Molecular Animal Breeding and Biotechnology, Ludwig Maximilians University, Munich (Germany); Meybohm, Patrick; Bein, Berthold; Steinfath, Markus; Scholz, Jens [Department of Anesthesiology and Intensive Care Medicine, University Hospital Schleswig-Holstein, Campus Kiel (Germany); Albrecht, Martin, E-mail: Albrecht@anaesthesie.uni-kiel.de [Department of Anesthesiology and Intensive Care Medicine, University Hospital Schleswig-Holstein, Campus Kiel (Germany)

    2010-09-03

    Research highlights: {yields} Levels of IL-1{beta} are increased in the pig myocardium after infarction. {yields} Cultured pig heart cells possess IL-1 receptors. {yields} IL-1{beta} increases cell proliferation of pig heart cells in-vitro. {yields} IL-1{beta} increases MMP-2 and MMP-9 activity in pig heart cells in-vitro. {yields} IL-1{beta} may be important for tissue remodelling events after myocardial infarction. -- Abstract: After myocardial infarction, elevated levels of interleukins (ILs) are found within the myocardial tissue and IL-1{beta} is considered to play a major role in tissue remodelling events throughout the body. In the study presented, we have established a cell culture model of primary pig heart cells to evaluate the effects of different concentrations of IL-1{beta} on cell proliferation as well as expression and activity of enzymes typically involved in tissue remodelling. Primary pig heart cell cultures were derived from three different animals and stimulated with recombinant pig IL-1{beta}. RNA expression was detected by RT-PCR, protein levels were evaluated by Western blotting, activity of matrix metalloproteinases (MMPs) was quantified by gelatine zymography and cell proliferation was measured using colorimetric MTS assays. Pig heart cells express receptors for IL-1 and application of IL-1{beta} resulted in a dose-dependent increase of cell proliferation (P < 0.05 vs. control; 100 ng/ml; 24 h). Gene expression of caspase-3 was increased by IL-1{beta} (P < 0.05 vs. control; 100 ng/ml; 3 h), and pro-caspase-3 but not active caspase was detected in lysates of pig heart cells by Western blotting. MMP-2 gene expression as well as enzymatic activities of MMP-2 and MMP-9 were increased by IL-1{beta} (P < 0.05 vs. control; 100 ng/ml; 3 h for gene expression, 48 and 72 h for enzymatic activities of MMP-2 and MMP-9, respectively). Our in vitro data suggest that IL-1{beta} plays a major role in the events of tissue remodelling in the heart. Combined

  11. Decellularized extracellular matrices produced from immortal cell lines derived from different parts of the placenta support primary mesenchymal stem cell expansion.

    Directory of Open Access Journals (Sweden)

    Gina D Kusuma

    Full Text Available Mesenchymal stem/stromal cells (MSCs exhibit undesired phenotypic changes during ex vivo expansion, limiting production of the large quantities of high quality primary MSCs needed for both basic research and cell therapies. Primary MSCs retain many desired MSC properties including proliferative capacity and differentiation potential when expanded on decellularized extracellular matrix (dECM prepared from primary MSCs. However, the need to use low passage number primary MSCs (passage 3 or lower to produce the dECM drastically limits the utility and impact of this technology. Here, we report that primary MSCs expanded on dECM prepared from high passage number (passage 25 human telomerase reverse transcriptase (hTERT transduced immortal MSC cell lines also exhibit increased proliferation and osteogenic differentiation. Two hTERT-transduced placenta-derived MSC cell lines, CMSC29 and DMSC23 [derived from placental chorionic villi (CMSCs and decidua basalis (DMSCs, respectively], were used to prepare dECM-coated substrates. These dECM substrates showed structural and biochemical differences. Primary DMSCs cultured on dECM-DMSC23 showed a three-fold increase in cell number after 14 days expansion in culture and increased osteogenic differentiation compared with controls. Primary CMSCs cultured on the dECM-DMSC23 exhibited a two-fold increase in cell number and increased osteogenic differentiation. We conclude that immortal MSC cell lines derived from different parts of the placenta produce dECM with varying abilities for supporting increased primary MSC expansion while maintaining important primary MSC properties. Additionally, this is the first demonstration of using high passage number cells to produce dECM that can promote primary MSC expansion, and this advancement greatly increases the feasibility and applicability of dECM-based technologies.

  12. Proportion of collagen type II in the extracellular matrix promotes the differentiation of human adipose-derived mesenchymal stem cells into nucleus pulposus cells.

    Science.gov (United States)

    Tao, Yiqing; Zhou, Xiaopeng; Liu, Dongyu; Li, Hao; Liang, Chengzhen; Li, Fangcai; Chen, Qixin

    2016-01-01

    During degeneration process, the catabolism of collagen type II and anabolism of collagen type I in nucleus pulposus (NP) may influence the bioactivity of transplanted cells. Human adipose-derived mesenchymal stem cells (hADMSCs) were cultured as a micromass or in a series of gradual proportion hydrogels of a mix of collagen types I and II. Cell proliferation and cytotoxicity were detected using CCK-8 and LDH assays respectively. The expression of differentiation-related genes and proteins, including SOX9, aggrecan, collagen type I, and collagen type II, was examined using RT-qPCR and Western blotting. Novel phenotypic genes were also detected by RT-qPCR and western blotting. Alcian blue and dimethylmethylene blue assays were used to investigate sulfate proteoglycan expression, and PI3K/AKT, MAPK/ERK, and Smad signaling pathways were examined by Western blotting. The results showed collagen hydrogels have good biocompatibility, and cell proliferation increased after collagen type II treatment. Expressions of SOX9, aggrecan, and collagen type II were increased in a collagen type II dependent manner. Sulfate proteoglycan synthesis increased in proportion to collagen type II concentration. Only hADMSCs highly expressed NP cell marker KRT19 in collagen type II culture. Additionally, phosphorylated Smad3, which is associated with phosphorylated ERK, was increased after collagen type II-stimulation. The concentration and type of collagen affect hADMSC differentiation into NP cells. Collagen type II significantly ameliorates hADMSC differentiation into NP cells and promotes extracellular matrix synthesis. Therefore, anabolism of collagen type I and catabolism of type II may attenuate the differentiation and biosynthesis of transplanted stem cells. © 2016 International Union of Biochemistry and Molecular Biology.

  13. Modulation of extracellular matrix proteins and hepatate stellate cell activation following gadolinium chloride induced Kuffer cell blockade in an experimental model of liver fibrosis/cirrhosis

    Directory of Open Access Journals (Sweden)

    Nilgün Tekkesin

    2013-06-01

    Full Text Available Hepatic fibrosis is now regarded as a common response to chronic liver injury; regardless of its nature (viral infections, alcohol abuse and metal overload. It is also characterized by excessive deposition of extracellular matrix (ECM components. The ECM is a dynamic complex of macromolecules that includes collagens, glycoproteins, and proteoglycans, such as laminin and fibronectin; it has been shown that it does not only support the tissue structure, but also plays a major role in cell adhesion, proliferation, and differentiation. Remodelling of the ECM may be the signal that facilitates lobular reorganization during liver regeneration after a liver injury. Much work has been done concerning the ECM synthesis and protein contents.

  14. The Impact of Alpha-Syntrophin Deletion on the Changes in Tissue Structure and Extracellular Diffusion Associated with Cell Swelling under Physiological and Pathological Conditions

    Czech Academy of Sciences Publication Activity Database

    Dmytrenko, Lesia; Cicanič, Michal; Anděrová, Miroslava; Voříšek, Ivan; Ottersen, O. P.; Syková, Eva; Vargová, Lýdia

    2013-01-01

    Roč. 8, č. 7 (2013), e68044 E-ISSN 1932-6203 R&D Projects: GA ČR GA309/09/1597; GA ČR(CZ) GAP303/11/2378; GA ČR(CZ) GBP304/12/G069 Institutional support: RVO:68378041 Keywords : extracellular space * diffusion parameters * cell swelling Subject RIV: FH - Neurology Impact factor: 3.534, year: 2013

  15. The effect of extracellular calcium and inorganic phosphate on the growth and osteogenic differentiation of mesenchymal stem cells in vitro: implication for bone tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Liu Yukan; Lu Qiaozhi; Ji Huijiao; Zhao Xiaoli; Zhang Ming [College of Life Science, ZheJiang University, Hangzhou 310058 (China); Pei Rui [XiJing Hospital, Fourth Military Medical University, Xi An 710032 (China); Zhou Guoshun [Huzhou Central Hospital, Huzhou, Zhejiang Province 313000 (China); Tang, Rui Kang, E-mail: Lyk_cn@yahoo.com.c [Department of Chemistry, College of Science, ZheJiang University, Hangzhou 310027 (China)

    2009-04-15

    The aim of this study is to demonstrate the effect of extracellular calcium ion (Ca{sup 2+}) and inorganic phosphate (Pi) concentrations on the growth and differentiation of bone-marrow-derived mesenchymal stem cells (MSCs), which is essential to understand the interaction between calcium phosphate ceramic (CPC) scaffolds and seeded cells during the construction of tissue-engineered bones. MSCs were separated from rabbits and cultured in media with different concentrations of Ca{sup 2+} and Pi supplements. Their proliferation, apoptosis, mineralization and osteogenic differentiation were determined by the MTT assay, TUNEL assay, Vonkossa stain and RT-PCR examination. A two-way ANOVA calculation with comparisons of estimated marginal means by LSD was used for statistical analysis. Results showed that the optimal extracellular Ca{sup 2+} and Pi concentrations for the cells to proliferate and differentiate were 1.8 mM and 0.09 mM, respectively, which are the concentrations supplied in many commonly used culture media such as DMEM and alpha-MEM. Cell proliferation and differentiation decreased significantly with greater or lower concentrations of the Pi supplement. Greater Pi concentrations also led to significant cell apoptosis. Greater Ca{sup 2+} concentrations did not change cell proliferation but significantly inhibited cell differentiation. In addition, greater Ca{sup 2+} concentrations could significantly enhance cell mineralization. In conclusion, extracellular Ca{sup 2+} and Pi significantly influence the growth and osteogenic differentiation of MSCs. It is important to take the cellular effect of Ca{sup 2+} and Pi into consideration when designing or constructing scaffolds for bone tissue engineering with CPC.

  16. Extracellular Vesicles from Human Liver Stem Cells Reduce Injury in an Ex Vivo Normothermic Hypoxic Rat Liver Perfusion Model.

    Science.gov (United States)

    Rigo, Federica; De Stefano, Nicola; Navarro-Tableros, Victor; David, Ezio; Rizza, Giorgia; Catalano, Giorgia; Gilbo, Nicholas; Maione, Francesca; Gonella, Federica; Roggio, Dorotea; Martini, Silvia; Patrono, Damiano; Salizzoni, Mauro; Camussi, Giovanni; Romagnoli, Renato

    2018-05-01

    The gold standard for organ preservation before transplantation is static cold storage, which is unable to fully protect suboptimal livers from ischemia/reperfusion injury. An emerging alternative is normothermic machine perfusion (NMP), which permits organ reconditioning. Here, we aimed to explore the feasibility of a pharmacological intervention on isolated rat livers by using a combination of NMP and human liver stem cells-derived extracellular vesicles (HLSC-EV). We established an ex vivo murine model of NMP capable to maintain liver function despite an ongoing hypoxic injury induced by hemodilution. Livers were perfused for 4 hours without (control group, n = 10) or with HLSC-EV (treated group, n = 9). Bile production was quantified; perfusate samples were collected hourly to measure metabolic (pH, pO2, pCO2) and cytolysis parameters (AST, alanine aminotransferase, lactate dehydrogenase). At the end of perfusion, we assessed HLSC-EV engraftment by immunofluorescence, tissue injury by histology, apoptosis by terminal deoxynucleotidyl transferase dUTP nick-end labeling assay, tissue hypoxia-inducible factor 1-α, and transforming growth factor-beta 1 RNA expression by quantitative reverse transcription-polymerase chain reaction. During hypoxic NMP, livers were able to maintain homeostasis and produce bile. In the treated group, AST (P = 0.018) and lactate dehydrogenase (P = 0.032) levels were significantly lower than those of the control group at 3 hours of perfusion, and AST levels persisted lower at 4 hours (P = 0.003). By the end of NMP, HLSC-EV had been uptaken by hepatocytes, and EV treatment significantly reduced histological damage (P = 0.030), apoptosis (P = 0.049), and RNA overexpression of hypoxia-inducible factor 1-α (P < 0.0001) and transforming growth factor-beta 1 (P = 0.014). HLSC-EV treatment, even in a short-duration model, was feasible and effectively reduced liver injury during hypoxic NMP.

  17. Analysis of extracellular RNA by digital PCR

    Directory of Open Access Journals (Sweden)

    Kenji eTakahashi

    2014-06-01

    Full Text Available The transfer of extracellular RNA is emerging as an important mechanism for intracellular communication. The ability for the transfer of functionally active RNA molecules from one cell to another within vesicles such as exosomes enables a cell to modulate cellular signaling and biological processes within recipient cells. The study of extracellular RNA requires sensitive methods for the detection of these molecules. In this methods article, we will describe protocols for the detection of such extracellular RNA using sensitive detection technologies such as digital PCR. These protocols should be valuable to researchers interested in the role and contribution of extracellular RNA to tumor cell biology.

  18. Dermal extracellular lipid in birds.

    Science.gov (United States)

    Stromberg, M W; Hinsman, E J; Hullinger, R L

    1990-01-01

    A light and electron microscopic study of the skin of domestic chickens, seagulls, and antarctic penguins revealed abundant extracellular dermal lipid and intracellular epidermal lipid. Dermal lipid appeared ultrastructurally as extracellular droplets varying from less than 1 micron to more than 25 microns in diameter. The droplets were often irregularly contoured, sometimes round, and of relatively low electron density. Processes of fibrocytes were often seen in contact with extracellular lipid droplets. Sometimes a portion of such a droplet was missing, and this missing part appeared to have been "digested away" by the cell process. In places where cells or cell processes are in contact with fact droplets, there are sometimes extracellular membranous whorls or fragments which have been associated with the presence of fatty acids. Occasionally (in the comb) free fat particles were seen in intimate contact with extravasated erythrocytes. Fat droplets were seen in the lumen of small dermal blood and lymph vessels. We suggest that the dermal extracellular lipid originates in the adipocyte layer and following hydrolysis the free fatty acids diffuse into the epidermis. Here they become the raw material for forming the abundant neutral lipid contained in many of the epidermal cells of both birds and dolphins. The heretofore unreported presence and apparently normal utilization of abundant extracellular lipid in birds, as well as the presence of relatively large droplets of neutral lipid in dermal vessels, pose questions which require a thorough reappraisal of present concepts of the ways in which fat is distributed and utilized in the body.

  19. Purinergic A2b Receptor Activation by Extracellular Cues Affects Positioning of the Centrosome and Nucleus and Causes Reduced Cell Migration*

    Science.gov (United States)

    Ou, Young; Chan, Gordon; Zuo, Jeremy; Rattner, Jerome B.; van der Hoorn, Frans A.

    2016-01-01

    The tight, relative positioning of the nucleus and centrosome in mammalian cells is important for the regulation of cell migration. Under pathophysiological conditions, the purinergic A2b receptor can regulate cell motility, but the underlying mechanism remains unknown. Expression of A2b, normally low, is increased in tissues experiencing adverse physiological conditions, including hypoxia and inflammation. ATP is released from such cells. We investigated whether extracellular cues can regulate centrosome-nucleus positioning and cell migration. We discovered that hypoxia as well as extracellular ATP cause a reversible increase in the distance between the centrosome and nucleus and reduced cell motility. We uncovered the underlying pathway: both treatments act through the A2b receptor and specifically activate the Epac1/RapGef3 pathway. We show that cells lacking A2b do not respond in this manner to hypoxia or ATP but transfection of A2b restores this response, that Epac1 is critically involved, and that Rap1B is important for the relative positioning of the centrosome and nucleus. Our results represent, to our knowledge, the first report demonstrating that pathophysiological conditions can impact the distance between the centrosome and nucleus. Furthermore, we identify the A2b receptor as a central player in this process. PMID:27226580

  20. Dependence of Relative Expression of NTR1 and EGFR on Cell Density and Extracellular pH in Human Pancreatic Cancer Cell Lines

    International Nuclear Information System (INIS)

    Olszewski-Hamilton, Ulrike; Hamilton, Gerhard

    2011-01-01

    Pancreatic adenocarcinoma is a devastating disease characterized by early dissemination and poor prognosis. These solid tumors express receptors for neuropeptides like neurotensin (NT) or epidermal growth factor (EGF) and exhibit acidic regions when grown beyond a certain size. We previously demonstrated increases in intracellular Ca 2+ levels, intracellular pH and interleukin-8 (IL-8) secretion in BxPC-3 and PANC-1 pancreatic cancer cells in response to a stable NT analog. The present study aimed at investigation of the dependence of the relative expression of NT receptor 1 (NTR1) and EGFR in BxPC-3 and MIA PaCa-2 cells on cell density and extracellular pH (pH e ). MTT assays revealed the NTR1 inhibitor SR 142948-sensitive Lys 8 -ψ-Lys 9 NT (8–13)-induced proliferation in BxPC-3 and PANC-1 cells. Confluent cultures of BxPC3 and HT-29 lines exhibited highest expression of NTR1 and lowest of EGFR and expression of NTR1 was maximal at slightly acidic pH e . IL-8 production was stimulated by Lys 8 -ψ-Lys 9 NT (8–13) and even enhanced at both acidic and alkaline pH e in BxPC-3 and PANC-1 cells. In conclusion, our in vitro study suggests that one contributing factor to the minor responses obtained with EGFR-directed therapy may be downregulation of this receptor in tumor cell aggregates, possibly resulting in acquisition of a more aggressive phenotype via other growth factor receptors like NTR1

  1. Static Mechanical Loading Influences the Expression of Extracellular Matrix and Cell Adhesion Proteins in Vaginal Cells Derived From Premenopausal Women With Severe Pelvic Organ Prolapse.

    Science.gov (United States)

    Kufaishi, Hala; Alarab, May; Drutz, Harold; Lye, Stephen; Shynlova, Oksana

    2016-08-01

    Primary human vaginal cells derived from women with severe pelvic organ prolapse (POP-HVCs) demonstrate altered cellular characteristics as compared to cells derived from asymptomatic women (control-HVCs). Using computer-controllable Flexcell stretch unit, we examined whether POP-HVCs react differently to mechanical loading as compared to control-HVCs by the expression of extracellular matrix (ECM) components, cell-ECM adhesion proteins, and ECM degrading and maturating enzymes. Vaginal tissue biopsies from premenopausal patients with Pelvic Organ Prolapse Quantification System stage ≥3 (n = 8) and asymptomatic controls (n = 7) were collected during vaginal hysterectomy or repair. Human vaginal cells were isolated by enzymatic digestion, seeded on collagen (COLI)-coated plates, and stretched (24 hours, 25% elongation). Total RNA was extracted, and 84 genes were screened using Human ECM and Adhesion Molecules polymerase chain reaction array; selected genes were verified by quantitative reverse transcription-polymerase chain reaction. Stretch-conditioned media (SCM) were collected and analyzed by protein array, immunoblotting, and zymography. In mechanically stretched control-HVCs, transcript levels of integrins (ITGA1, ITGA4, ITGAV, and ITGB1) and matrix metalloproteinases (MMPs) 2, 8, and 13 were downregulated (P SCM from POP-HVCs compared to control-HVCs. Primary human vaginal cells derived from women with severe pelvic organ prolapse and control-HVCs react differentially to in vitro mechanical stretch. Risk factors that induce stretch may alter ECM composition and cell-ECM interaction in pelvic floor tissue leading to the abatement of pelvic organ support and subsequent POP development. © The Author(s) 2016.

  2. Bioengineering vascularized tissue constructs using an injectable cell-laden enzymatically crosslinked collagen hydrogel derived from dermal extracellular matrix.

    Science.gov (United States)

    Kuo, Kuan-Chih; Lin, Ruei-Zeng; Tien, Han-Wen; Wu, Pei-Yun; Li, Yen-Cheng; Melero-Martin, Juan M; Chen, Ying-Chieh

    2015-11-01

    -Ph hydrogel resulted in not only improving the long-term differentiation of transplanted MSCs into mineralized osteoblasts, but the collagen-Ph hydrogel also improved an increased of adipocytes within the vascularized bioengineered tissue in a mouse after 1 month of implantation. We reported a method for preparing autologous extracellular matrix scaffolds, murine collagen-Ph hydrogels, and demonstrated its suitability for use in supporting human progenitor cell-based formation of 3D vascular networks in vitro and in vivo. Results showed extensive human vascular networks can be generated within 7 days, engineered vascular density inside collagen-Ph constructs can be manipulated through refinable mechanical properties and proteolytic degradability, and these networks can form functional anastomoses with existing vasculature to further support the survival of host muscle tissues. Moreover, optimized conditions of cell-laden collagen-Ph hydrogel resulted in not only improving the long-term differentiation of transplanted MSCs into mineralized osteoblasts, but the collagen-Ph hydrogel also improved an increased of adipocytes within the vascularized bioengineered tissue in a mouse. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  3. The extracellular adherence protein (Eap) of Staphylococcus aureus acts as a proliferation and migration repressing factor that alters the cell morphology of keratinocytes.

    Science.gov (United States)

    Eisenbeis, Janina; Peisker, Henrik; Backes, Christian S; Bur, Stephanie; Hölters, Sebastian; Thewes, Nicolas; Greiner, Markus; Junker, Christian; Schwarz, Eva C; Hoth, Markus; Junker, Kerstin; Preissner, Klaus T; Jacobs, Karin; Herrmann, Mathias; Bischoff, Markus

    2017-02-01

    Staphyloccocus aureus is a major human pathogen and a common cause for superficial and deep seated wound infections. The pathogen is equipped with a large arsenal of virulence factors, which facilitate attachment to various eukaryotic cell structures and modulate the host immune response. One of these factors is the extracellular adherence protein Eap, a member of the "secretable expanded repertoire adhesive molecules" (SERAM) protein family that possesses adhesive and immune modulatory properties. The secreted protein was previously shown to impair wound healing by interfering with host defense and neovascularization. However, its impact on keratinocyte proliferation and migration, two major steps in the re-epithelialization process of wounds, is not known. Here, we report that Eap affects the proliferation and migration capacities of keratinocytes by altering their morphology and adhesive properties. In particular, treatment of non-confluent HaCaT cell cultures with Eap resulted in cell morphology changes as well as a significant reduction in cell proliferation and migration. Eap-treated HaCaT cells changed their appearance from an oblong via a trapezoid to an astral-like shape, accompanied by decreases in cell volume and cell stiffness, and exhibited significantly increased cell adhesion. Eap had a similar influence on endothelial and cancer cells, indicative for a general effect of Eap on eukaryotic cell morphology and functions. Specifically, Eap was found to interfere with growth factor-stimulated activation of the mitogen-activated protein kinase (MAPK) pathway that is known to be responsible for cell shape modulation, induction of proliferation and migration of epithelial cells. Western blot analyses revealed that Eap blocked the phosphorylation of extracellular signal-regulated kinase 1 and 2 (Erk1/2) in keratinocyte growth factor (KGF)-stimulated HaCaT cells. Together, these data add another antagonistic mechanism of Eap in wound healing, whereby the

  4. Moderate extracellular acidification inhibits capsaicin-induced cell death through regulating calcium mobilization, NF-{kappa}B translocation and ROS production in synoviocytes

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Fen; Yang, Shuang; Zhao, Dan; Zhu, Shuyan; Wang, Yuxiang [Department of Biophysics, School of Physics and Key Laboratory of Bioactive Materials of Education Ministry, Nankai University, Tianjin 300071 (China); Li, Junying, E-mail: jyli04@nankai.edu.cn [Department of Biophysics, School of Physics and Key Laboratory of Bioactive Materials of Education Ministry, Nankai University, Tianjin 300071 (China)

    2012-07-20

    Highlights: Black-Right-Pointing-Pointer Moderate extracellular acidification regulates intracellular Ca{sup 2+} mobilization. Black-Right-Pointing-Pointer Moderate acidification activates NF-{kappa}B nuclear translocation in synoviocytes. Black-Right-Pointing-Pointer Moderate acidification depresses the ROS production induced by capsaicin. Black-Right-Pointing-Pointer Moderate acidification inhibits capsaicin-caused synoviocyte death. -- Abstract: We previously show the expression of transient receptor potential vanilloid 1 (TRPV1) in primary synoviocytes from collagen-induced arthritis (CIA) rats. Capsaicin and lowered extracellular pH from 7.4 to 5.5 induce cell death through TRPV1-mediated Ca{sup 2+} entry and reactive oxygen species (ROS) production. However, under the pathological condition in rheumatoid arthritis, the synovial fluid is acidified to a moderate level (about pH 6.8). In the present study, we examined the effects of pH 6.8 on the TRPV1-mediated cell death. Our finding is different or even opposite from what was observed at pH 5.5. We found that the moderate extracellular acidification (from pH 7.4 to 6.8) inhibited the capsaicin-induced Ca{sup 2+} entry through attenuating the activity of TRPV1. In the mean time, it triggered a phospholipse C (PLC)-related Ca{sup 2+} release from intracellular stores. The nuclear translocation of NF-{kappa}B was found at pH 6.8, and this also depends on PLC activation. Moreover, the capsaicin-evoked massive ROS production and cell death were depressed at pH 6.8, both of which are dependent on the activation of PLC and NF-{kappa}B. Taken together, these results suggested that the moderate extracellular acidification inhibited the capsaicin-induced synoviocyte death through regulating Ca{sup 2+} mobilization, activating NF-{kappa}B nuclear translocation and depressing ROS production.

  5. Moderate extracellular acidification inhibits capsaicin-induced cell death through regulating calcium mobilization, NF-κB translocation and ROS production in synoviocytes

    International Nuclear Information System (INIS)

    Hu, Fen; Yang, Shuang; Zhao, Dan; Zhu, Shuyan; Wang, Yuxiang; Li, Junying

    2012-01-01

    Highlights: ► Moderate extracellular acidification regulates intracellular Ca 2+ mobilization. ► Moderate acidification activates NF-κB nuclear translocation in synoviocytes. ► Moderate acidification depresses the ROS production induced by capsaicin. ► Moderate acidification inhibits capsaicin-caused synoviocyte death. -- Abstract: We previously show the expression of transient receptor potential vanilloid 1 (TRPV1) in primary synoviocytes from collagen-induced arthritis (CIA) rats. Capsaicin and lowered extracellular pH from 7.4 to 5.5 induce cell death through TRPV1-mediated Ca 2+ entry and reactive oxygen species (ROS) production. However, under the pathological condition in rheumatoid arthritis, the synovial fluid is acidified to a moderate level (about pH 6.8). In the present study, we examined the effects of pH 6.8 on the TRPV1-mediated cell death. Our finding is different or even opposite from what was observed at pH 5.5. We found that the moderate extracellular acidification (from pH 7.4 to 6.8) inhibited the capsaicin-induced Ca 2+ entry through attenuating the activity of TRPV1. In the mean time, it triggered a phospholipse C (PLC)-related Ca 2+ release from intracellular stores. The nuclear translocation of NF-κB was found at pH 6.8, and this also depends on PLC activation. Moreover, the capsaicin-evoked massive ROS production and cell death were depressed at pH 6.8, both of which are dependent on the activation of PLC and NF-κB. Taken together, these results suggested that the moderate extracellular acidification inhibited the capsaicin-induced synoviocyte death through regulating Ca 2+ mobilization, activating NF-κB nuclear translocation and depressing ROS production.

  6. Drugs elevating extracellular adenosine enhance cell cycling of hematopoietic progenitor cells as inferred from the cytotoxic effects of 5-fluorouracil

    Czech Academy of Sciences Publication Activity Database

    Pospíšil, Milan; Hofer, Michal; Vacek, Antonín; Netíková, Jaromíra; Holá, Jiřina; Znojil, V.; Weiterová, Lenka

    2001-01-01

    Roč. 29, č. 5 (2001), s. 557-562 ISSN 0301-472X R&D Projects: GA ČR GA306/99/0027; GA AV ČR IBS5004009 Institutional research plan: CEZ:AV0Z5004920 Keywords : colony-stimulating factor * smooth-muscle cells * irradiated mice Subject RIV: BO - Biophysics Impact factor: 3.328, year: 2001

  7. Mesenchymal stem cell-derived extracellular matrix enhances chondrogenic phenotype of and cartilage formation by encapsulated chondrocytes in vitro and in vivo.

    Science.gov (United States)

    Yang, Yuanheng; Lin, Hang; Shen, He; Wang, Bing; Lei, Guanghua; Tuan, Rocky S

    2018-03-15

    Mesenchymal stem cell derived extracellular matrix (MSC-ECM) is a natural biomaterial with robust bioactivity and good biocompatibility, and has been studied as a scaffold for tissue engineering. In this investigation, we tested the applicability of using decellularized human bone marrow derived MSC-ECM (hBMSC-ECM) as a culture substrate for chondrocyte expansion in vitro, as well as a scaffold for chondrocyte-based cartilage repair. hBMSC-ECM deposited by hBMSCs cultured on tissue culture plastic (TCP) was harvested, and then subjected to a decellularization process to remove hBMSCs. Compared with chondrocytes grown on TCP, chondrocytes seeded onto hBMSC-ECM exhibited significantly increased proliferation rate, and maintained better chondrocytic phenotype than TCP group. After being expanded to the same cell number and placed in high-density micromass cultures, chondrocytes from the ECM group showed better chondrogenic differentiation profile than those from the TCP group. To test cartilage formation ability, composites of hBMSC-ECM impregnated with chondrocytes were subjected to brief trypsin treatment to allow cell-mediated contraction, and folded to form 3-dimensional chondrocyte-impregnated hBMSC-ECM (Cell/ECM constructs). Upon culture in vitro in chondrogenic medium for 21 days, robust cartilage formation was observed in the Cell/ECM constructs. Similarly prepared Cell/ECM constructs were tested in vivo by subcutaneous implantation into SCID mice. Prominent cartilage formation was observed in the implanted Cell/ECM constructs 14 days post-implantation, with higher sGAG deposition compared to controls consisting of chondrocyte cell sheets. Taken together, these findings demonstrate that hBMSC-ECM is a superior culture substrate for chondrocyte expansion and a bioactive matrix potentially applicable for cartilage regeneration in vivo. Current cell-based treatments for focal cartilage defects face challenges, including chondrocyte dedifferentiation, need for

  8. Modulation of intracellular Ca2+ via L-type calcium channels in heart cells by the autoantibody directed against the second extracellular loop of the alpha1-adrenoceptors.

    Science.gov (United States)

    Bkaily, Ghassan; El-Bizri, Nesrine; Bui, Michel; Sukarieh, Rami; Jacques, Danielle; Fu, Michael L X

    2003-03-01

    The effects of methoxamine, a selective alpha1-adrenergic receptor agonist, and the autoantibody directed against the second extracellular loop of alpha1-adrenoceptors were studied on intracellular free Ca2+ levels using confocal microscopy and ionic currents using the whole-cell patch clamp technique in single cells of 10-day-old embryonic chick and 20-week-old fetal human hearts. We observed that like methoxamine, the autoantibody directed against the second extracellular loop of alpha1-adrenoreceptors significantly increased the L-type calcium current (I(Ca(L))) but had no effect on the T-type calcium current (I(Ca(T))), the delayed outward potassium current, or the fast sodium current. This effect of the autoantibody was prevented by a prestimulation of the receptors with methoxamine and vice versa. Moreover, treating the cells with prazosin, a selective alpha1-adrenergic receptor antagonist blocked the methoxamine and the autoantibody-induced increase in I(Ca(L)), respectively. In absence of prazosin, both methoxamine and the autoantibody showed a substantial enhancement in the frequency of cell contraction and that of the concomitant cytosolic and nuclear free Ca2+ variations. The subsequent addition of nifedipine, a specific L-type Ca2+ channel blocker, reversed not only the methoxamine or the autoantibody-induced effect but also completely abolished cell contraction. These results demonstrated that functional alpha1-adrenoceptors exist in both 10-day-old embryonic chick and 20-week-old human fetal hearts and that the autoantibody directed against the second extracellular loop of this type of receptors plays an important role in stimulating their activity via activation of L-type calcium channels. This loop seems to have a functional significance by being the target of alpha1-receptor agonists like methoxamine.

  9. Simultaneous quantification of monoamine neurotransmitters and their biogenic metabolites intracellularly and extracellularly in primary neuronal cell cultures and in sub-regions of guinea pig brain.

    Science.gov (United States)

    Schou-Pedersen, Anne Marie V; Hansen, Stine N; Tveden-Nyborg, Pernille; Lykkesfeldt, Jens

    2016-08-15

    In the present paper, we describe a validated chromatographic method for the simultaneous quantification of monoamine neurotransmitters and their biogenic metabolites intracellularly and extracellularly in primary neuronal cell culture and in sub-regions of the guinea pig brain. Electrochemical detection provided limits of quantifications (LOQs) between 3.6 and 12nM. Within the linear range, obtained recoveries were from 90.9±9.9 to 120±14% and intra-day and inter-day precisions found to be less than 5.5% and 12%, respectively. The analytical method was applicable for quantification of intracellular and extracellular amounts of monoamine neurotransmitters and their metabolites in guinea pig frontal cortex and hippocampal primary neuronal cell cultures. Noradrenaline, dopamine and serotonin were found to be in a range from 0.31 to 1.7pmol per 2 million cells intracellularly, but only the biogenic metabolites could be detected extracellularly. Distinct differences in monoamine concentrations were observed when comparing concentrations in guinea pig frontal cortex and cerebellum tissue with higher amounts of dopamine and its metabolites, 3,4-dihydroxyphenylacetic acid and homovanillic acid in frontal cortex, as compared to cerebellum. The chemical turnover in frontal cortex tissue of guinea pig was for serotonin successfully predicted from the turnover observed in the frontal cortex cell culture. In conclusion, the present analytical method shows high precision, accuracy and sensitivity and is broadly applicable to monoamine measurements in cell cultures as well as brain biopsies from animal models used in preclinical neurochemistry. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Impedance Spectroscopy as a Tool for Non-Intrusive Detection of Extracellular Mediators in Microbial Fuel Cells

    Science.gov (United States)

    2009-12-01

    2005; Marsili et al., 2008; Myers and Myers, 2004; Newman and Kolter , 2000; Rosso et al., 2003; vonCanstein et al., 2008; Ward et al., 2004). In an... Kolter R. 2000. A role for excreted quinones in extracellular electron transfer. Nature 405:94. Rabaey K, Boon N, Siciliano SD, Verhaege M, Verstraete W

  11. Influence of tissue- and cell-scale extracellular matrix distribution on the mechanical properties of tissue-engineered cartilage

    NARCIS (Netherlands)

    Khoshgoftar, M.; Wilson, W.; Ito, K.; Donkelaar, C.C. van

    2013-01-01

    The insufficient load-bearing capacity of today's tissue- engineered (TE) cartilage limits its clinical application. Generally, cartilage TE studies aim to increase the extracellular matrix (ECM) content, as this is thought to determine the load-bearing properties of the cartilage. However, there

  12. Influence of tissue- and cell-scale extracellular matrix distribution on the mechanical properties of tissue engineered cartilage

    NARCIS (Netherlands)

    Khoshgoftar, M.; Wilson, W.; Ito, K.; Donkelaar, van C.C.

    2013-01-01

    The insufficient load-bearing capacity of today’s tissue- engineered (TE) cartilage limits its clinical application. Generally, cartilage TE studies aim to increase the extracellular matrix (ECM) content, as this is thought to determine the load-bearing properties of the cartilage. However, there

  13. Extracellular Bio-imaging of Acetylcholine-stimulated PC12 Cells Using a Calcium and Potassium Multi-ion Image Sensor.

    Science.gov (United States)

    Matsuba, Sota; Kato, Ryo; Okumura, Koichi; Sawada, Kazuaki; Hattori, Toshiaki

    2018-01-01

    In biochemistry, Ca 2+ and K + play essential roles to control signal transduction. Much interest has been focused on ion-imaging, which facilitates understanding of their ion flux dynamics. In this paper, we report a calcium and potassium multi-ion image sensor and its application to living cells (PC12). The multi-ion sensor had two selective plasticized poly(vinyl chloride) membranes containing ionophores. Each region on the sensor responded to only the corresponding ion. The multi-ion sensor has many advantages including not only label-free and real-time measurement but also simultaneous detection of Ca 2+ and K + . Cultured PC12 cells treated with nerve growth factor were prepared, and a practical observation for the cells was conducted with the sensor. After the PC12 cells were stimulated by acetylcholine, only the extracellular Ca 2+ concentration increased while there was no increase in the extracellular K + concentration. Through the practical observation, we demonstrated that the sensor was helpful for analyzing the cell events with changing Ca 2+ and/or K + concentration.

  14. MiRNAs and piRNAs from bone marrow mesenchymal stem cell extracellular vesicles induce cell survival and inhibit cell differentiation of cord blood hematopoietic stem cells: a new insight in transplantation.

    Science.gov (United States)

    De Luca, Luciana; Trino, Stefania; Laurenzana, Ilaria; Simeon, Vittorio; Calice, Giovanni; Raimondo, Stefania; Podestà, Marina; Santodirocco, Michele; Di Mauro, Lazzaro; La Rocca, Francesco; Caivano, Antonella; Morano, Annalisa; Frassoni, Francesco; Cilloni, Daniela; Del Vecchio, Luigi; Musto, Pellegrino

    2016-02-09

    Hematopoietic stem cells (HSC), including umbilical cord blood CD34+ stem cells (UCB-CD34+), are used for the treatment of several diseases. Although different studies suggest that bone marrow mesenchymal stem cells (BM-MSC) support hematopoiesis, the exact mechanism remains unclear. Recently, extracellular vesicles (EVs) have been described as a novel avenue of cell communication, which may mediate BM-MSC effect on HSC. In this work, we studied the interaction between UCB-CD34+ cells and BM-MSC derived EVs. First, by sequencing EV derived miRNAs and piRNAs we found that EVs contain RNAs able to influence UCB-CD34+ cell fate. Accordingly, a gene expression profile of UCB-CD34+ cells treated with EVs, identified about 100 down-regulated genes among those targeted by EV-derived miRNAs and piRNAs (e.g. miR-27b/MPL, miR-21/ANXA1, miR-181/EGR2), indicating that EV content was able to modify gene expression profile of receiving cells. Moreover, we demonstrated that UCB-CD34+ cells, exposed to EVs, significantly changed different biological functions, becoming more viable and less differentiated. UCB-CD34+ gene expression profile also identified 103 up-regulated genes, most of them codifying for chemokines, cytokines and their receptors, involved in chemotaxis of different BM cells, an essential function of hematopoietic reconstitution. Finally, the exposure of UCB-CD34+ cells to EVs caused an increased expression CXCR4, paralleled by an in vivo augmented migration from peripheral blood to BM niche in NSG mice. This study demonstrates the existence of a powerful cross talk between BM-MSC and UCB-CD34+ cells, mediated by EVs, providing new insight in the biology of cord blood transplantation.

  15. Up-regulated Ectonucleotidases in Fas-Associated Death Domain Protein- and Receptor-Interacting Protein Kinase 1-Deficient Jurkat Leukemia Cells Counteract Extracellular ATP/AMP Accumulation via Pannexin-1 Channels during Chemotherapeutic Drug-Induced Apoptosis.

    Science.gov (United States)

    Boyd-Tressler, Andrea M; Lane, Graham S; Dubyak, George R

    2017-07-01

    Pannexin-1 (Panx1) channels mediate the efflux of ATP and AMP from cancer cells in response to induction of extrinsic apoptosis by death receptors or intrinsic apoptosis by chemotherapeutic agents. We previously described the accumulation of extracellular ATP /AMP during chemotherapy-induced apoptosis in Jurkat human leukemia cells. In this study, we compared how different signaling pathways determine extracellular nucleotide pools in control Jurkat cells versus Jurkat lines that lack the Fas-associated death domain (FADD) or receptor-interacting protein kinase 1 (RIP1) cell death regulatory proteins. Tumor necrosis factor- α induced extrinsic apoptosis in control Jurkat cells and necroptosis in FADD-deficient cells; treatment of both lines with chemotherapeutic drugs elicited similar intrinsic apoptosis. Robust extracellular ATP/AMP accumulation was observed in the FADD-deficient cells during necroptosis, but not during apoptotic activation of Panx1 channels. Accumulation of extracellular ATP/AMP was similarly absent in RIP1-deficient Jurkat cells during apoptotic responses to chemotherapeutic agents. Apoptotic activation triggered equivalent proteolytic gating of Panx1 channels in all three Jurkat cell lines. The differences in extracellular ATP/AMP accumulation correlated with cell-line-specific expression of ectonucleotidases that metabolized the released ATP/AMP. CD73 mRNA, and α β -methylene-ADP-inhibitable ecto-AMPase activity were elevated in the FADD-deficient cells. In contrast, the RIP1-deficient cells were defined by increased expression of tartrate-sensitive prostatic acid phosphatase as a broadly acting ectonucleotidase. Thus, extracellular nucleotide accumulation during regulated tumor cell death involves interplay between ATP/AMP efflux pathways and different cell-autonomous ectonucleotidases. Differential expression of particular ectonucleotidases in tumor cell variants will determine whether chemotherapy-induced activation of Panx1 channels

  16. Caveolin 3-mediated integrin β1 signaling is required for the proliferation of folliculostellate cells in rat anterior pituitary gland under the influence of extracellular matrix.

    Science.gov (United States)

    Horiguchi, Kotaro; Fujiwara, Ken; Ilmiawati, Cimi; Kikuchi, Motoshi; Tsukada, Takehiro; Kouki, Tom; Yashiro, Takashi

    2011-07-01

    Folliculostellate (FS) cells in the anterior pituitary gland are believed to have multifunctional properties. Using transgenic rats that express green fluorescent protein (GFP) specifically in FS cells in the anterior pituitary gland (S100b-GFP rats), we recently revealed that FS cells in primary culture exhibited marked proliferation in the presence of laminin, an extracellular matrix (ECM) component of the basement membrane. In a process referred to as matricrine action, FS cells receive ECM as a signal through their receptors, which results in morphological and functional changes. In this study, we investigated matricrine signaling in FS cells and observed that the proliferation of FS cells is mediated by integrin β1, which is involved in various signaling pathways for cell migration and proliferation in response to ECM. Then, we analyzed downstream events of the integrin β1 signaling pathway in the proliferation of FS cells and identified caveolin 3 as a potential candidate molecule. Caveolin 3 is a membrane protein that binds cholesterol and a number of signaling molecules that interact with integrin β1. Using specific small interfering RNA of caveolin 3, the proliferation of FS cells was inhibited. Furthermore, caveolin 3 drove activation of the mitogen-activated protein kinase (MAPK) signaling cascades, which resulted in upregulation of cyclin D1 in FS cells. These findings suggest that matricrine signaling in the proliferation of FS cells was transduced by a caveolin 3-mediated integrin β1 signaling pathway and subsequent activation of the MAPK pathway. © 2011 Society for Endocrinology

  17. Enhancement of Muscle T Regulatory Cells and Improvement of Muscular Dystrophic Process in mdx Mice by Blockade of Extracellular ATP/P2X Axis.

    Science.gov (United States)

    Gazzerro, Elisabetta; Baldassari, Simona; Assereto, Stefania; Fruscione, Floriana; Pistorio, Angela; Panicucci, Chiara; Volpi, Stefano; Perruzza, Lisa; Fiorillo, Chiara; Minetti, Carlo; Traggiai, Elisabetta; Grassi, Fabio; Bruno, Claudio

    2015-12-01

    Infiltration of immune cells and chronic inflammation substantially affect skeletal and cardiac muscle degeneration in Duchenne muscular dystrophy. In the immune system, extracellular adenosine triphosphate (ATP) released by dying cells is sensed as a danger associated molecular pattern through P2 purinergic receptors. Specifically, the P2X7 subtype has a prominent role in regulating immune system physiology and contributes to inflammasome activation also in muscle cells. Here, we show that in vivo blockade of the extracellular ATP/P2X purinergic signaling pathway by periodate-oxidized ATP delayed the progression of the dystrophic phenotype and dampened the local inflammatory response in mdx mice, a spontaneous mouse model of dystrophin deficiency. Reduced infiltration of leukocytes and macrophages and decreased expression of IL-6 were revealed in the muscles of periodate-oxidized ATP-treated mdx mice. Concomitantly, an increase in Foxp3(+) immunosuppressive regulatory T cells was observed and correlated with enhanced myofiber regeneration. Moreover, we detected reduced concentrations of profibrotic cytokines, including transforming growth factor-β and connective tissue growth factor, in muscles of periodate-oxidized ATP-treated mdx mice. The improvement of inflammatory features was associated with increased strength and reduced necrosis, thus suggesting that pharmacologic purinergic antagonism altering the adaptive immune component in the muscle infiltrates might represent a promising therapeutic approach in Duchenne muscular dystrophy. Copyright © 2015 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  18. PDGF-mediated protection of SH-SY5Y cells against Tat toxin involves regulation of extracellular glutamate and intracellular calcium

    International Nuclear Information System (INIS)

    Zhu Xuhui; Yao Honghong; Peng Fuwang; Callen, Shannon; Buch, Shilpa

    2009-01-01

    The human immunodeficiency virus (HIV-1) protein Tat has been implicated in mediating neuronal apoptosis, one of the hallmark features of HIV-associated dementia (HAD). Mitigation of the toxic effects of Tat could thus be a potential mechanism for reducing HIV toxicity in the brain. In this study we demonstrated that Tat-induced neurotoxicity was abolished by NMDA antagonist-MK801, suggesting the role of glutamate in this process. Furthermore, we also found that pretreatment of SH-SY5Y cells with PDGF exerted protection against Tat toxicity by decreasing extracellular glutamate levels. We also demonstrated that extracellular calcium chelator EGTA was able to abolish PDGF-mediated neuroprotection, thereby underscoring the role of calcium signaling in PDGF-mediated neuroprotection. We also showed that Erk signaling pathway was critical for PDGF-mediated protection of cells. Additionally, blocking calcium entry with EGTA resulted in suppression of PDGF-induced Erk activation. These findings thus underscore the role of PDGF-mediated calcium signaling and Erk phosphorylation in the protection of cells against HIV Tat toxicity.

  19. Depletion of intracellular calcium stores facilitates the influx of extracellular calcium in platelet derived growth factor stimulated A172 glioblastoma cells.

    Science.gov (United States)

    Vereb, G; Szöllösi, J; Mátyus, L; Balázs, M; Hyun, W C; Feuerstein, B G

    1996-05-01

    Calcium signaling in non-excitable cells is the consequence of calcium release from intracellular stores, at times followed by entry of extracellular calcium through the plasma membrane. To study whether entry of calcium depends upon the level of saturation of intracellular stores, we measured calcium channel opening in the plasma membrane of single confluent A172 glioblastoma cells stimulated with platelet derived growth factor (PDGF) and/or bradykinin (BK). We monitored the entry of extracellular calcium by measuring manganese quenching of Indo-1 fluorescence. PDGF raised intracellular calcium concentration ([Ca2+]i) after a dose-dependent delay (tdel) and then opened calcium channels after a dose-independent delay (tch). At higher doses (> 3 nM), BK increased [Ca2+]i after a tdel approximately 0 s, and tch decreased inversely with both dose and peak [Ca2+]i. Experiments with thapsigargin (TG), BK, and PDGF indicated that BK and PDGF share intracellular Ca2+ pools that are sensitive to TG. When these stores were depleted by treatment with BK and intracellular BAPTA, tdel did not change, but tch fell to almost 0 s in PDGF stimulated cells, indicating that depletion of calcium stores affects calcium channel opening in the plasma membrane. Our data support the capacitative model for calcium channel opening and the steady-state model describing quantal Ca2+ release from intracellular stores.

  20. Lactobacillus reuteri Strains Convert Starch and Maltodextrins into Homoexopolysaccharides Using an Extracellular and Cell-Associated 4,6-α-Glucanotransferase.

    Science.gov (United States)

    Bai, Yuxiang; Böger, Markus; van der Kaaij, Rachel Maria; Woortman, Albert Jan Jacob; Pijning, Tjaard; van Leeuwen, Sander Sebastiaan; van Bueren, Alicia Lammerts; Dijkhuizen, Lubbert

    2016-04-13

    Exopolysaccharides (EPS) of lactic acid bacteria (LAB) are of interest for food applications. LAB are well-known to produce α-glucan from sucrose by extracellular glucansucrases. Various Lactobacillus reuteri strains also possess 4,6-α-glucanotransferase (4,6-α-GTase) enzymes. Purified 4,6-α-GTases (e.g., GtfB) were shown to act on starches (hydrolysates), cleaving α1→4 linkages and synthesizing α1→6 linkages, yielding isomalto-/maltopolysaccharides (IMMP). Here we report that also L. reuteri cells with these extracellular, cell-associated 4,6-α-GTases synthesize EPS (α-glucan) from starches (hydrolysates). NMR, SEC, and enzymatic hydrolysis of EPS synthesized by L. reuteri 121 cells showed that these have simil